Neonatal Resuscitation.pdf

Neonatal Resuscitation Rosemarie Boland OVERVIEW The vast majority of newborn babies undergo a successful transition to extrauterine life without the need for any intervention other than drying, provision of warmth and ensuring a clear airway. Fewer than 6% of all newborn babies in Australia require assistance to establish eﬀective respirations with positive pressure ventilation. Less than 0.2% require advanced resuscitation interventions (external cardiac compressions, intubation and drug administration). Newborn babies are cyanosed or 'dusky’ when they are born. This is normal and does not require any intervention if the baby is breathing or crying and has a heart rate above 100 bpm. The key to successful resuscitation in newborn babies is eﬀective ventilation. When performed correctly, positive pressure ventilation results in a rapid improvement in heart rate, usually without the administration of supplementary oxygen. If positive pressure ventilation is required, room air (21% oxygen) should be used initially, as it has been shown to result in a signiﬁcantly lower mortality rate compared with using 100% oxygen. High-ﬂow 100% oxygen is indicated only if the newborn has a heart rate less than 60 bpm after at least 30 seconds of eﬀective positive pressure ventilation in air. Preterm birth (before 37 completed weeks’ gestation) is associated with a higher risk of stillbirth and infant mortality and morbidity. In 2017, there were 806 planned home births reported nationally in Australia, representing 0.3% of all births. Unintentional home births are rare. The lack of exposure to neonates requiring resuscitation suggests that paramedics should use an algorithmic approach to these cases to ensure all basic care is delivered. Introduction Live birth is deﬁned as the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy, which, after such separation, breathes or shows any other evidence of life, such as beating of the heart, pulsation of the umbilical cord or deﬁnite movement of voluntary muscles, whether or not the umbilical cord has been cut or the placenta is a ached (Australian Institute of Health and Welfare [AIHW], 2019). A stillbirth (fetal death) is deﬁned as a death occurring prior to the complete expulsion or extraction from the mother of a product of conception of 20 or more completed weeks’ gestation or 400 g or more birth weight. The stillbirth rate remains constant in Australia at 7.1 per 1000 births (AIHW, 2019). Babies are considered full term between 37 and 42 completed weeks’ gestation. Post-term birth is birth that occurs after 42 or more completed weeks’ gestation. Preterm birth is deﬁned as birth before 37 completed weeks’ gestation (AIHW, 2019). In 2017, 8.7% of babies born in Australia were preterm, with most preterm births occurring between 32 and 36 weeks’ gestation (AIHW, 2019). Preterm birth is associated with a higher risk of mortality and morbidity. These risks are even higher when preterm birth occurs in an out-of-hospital se ing (Boland et al., 2018). Viability is the earliest gestational age at which a newborn baby can survive outside the mother's womb. This is currently 22–23 weeks’ gestation for live born babies admi ed to a neonatal intensive care unit (NICU) in Australia or New Zealand (Chow et al., 2019). Of the 101 babies born < 24 weeks’ gestation in Australia and New Zealand who were oﬀered neonatal intensive care in 2017, 55 (55%) survived to discharge home (Chow et al., 2019). By 24 weeks’ gestation, 68% of babies oﬀered intensive care survived to hospital discharge. It is important to note that a 'viable’ baby born at 22–24 weeks’ gestation may not necessarily be resuscitated and oﬀered intensive care. At periviable gestational ages (22–24 weeks), many parents decide neonatal intensive care is not in the best interests of their baby and opt for comfort (palliative) care at birth. These decisions are based on the risks of neurosensory impairment (deafness, blindness) and disability (cerebral palsy) in surviving children and their predicted quality of life. Between 2009 and 2016 in Victoria, 5% of babies born at 22 weeks and 40% of babies born at 23 weeks were oﬀered intensive care. All those not oﬀered intensive care died at their birth hospital (Boland & Doyle, 2019). By 24 weeks’ gestation, 85% were oﬀered intensive care. In Western Australia, 8% of 22-week babies, 81% of 23-week babies and 95% of 24-week babies were oﬀered intensive care between 2004 and 2010 (Sharp et al., 2018). Hence, when interpreting survival data for periviable babies, it is critical to determine if the denominator is all live births or only babies oﬀered neonatal intensive care and to be aware that the provision of active versus palliative care will inﬂuence survival data. Survival rates are signiﬁcantly lower for babies born very preterm (28– 31 weeks) and extremely preterm (22–27 weeks) in the out-of-hospital environment (Boland et al., 2016; Stewart et al., 2017; Boland et al., 2018). In Victoria, only 5 babies born before 27 weeks’ gestation have survived following out-of-hospital birth over a 20-year period from 1990–2009 (Boland et al., 2018). Babies born in the out-of-hospital environment are also twice as likely to be stillborn compared with babies born in a hospital at 22–27 weeks’ gestation and four times as likely to be stillborn at 28–31 weeks’ gestation (Boland et al., 2018). Spontaneous preterm labour will often occur within days of fetal death in utero. If equipment to monitor fetal heart rate in transit to hospital is not available, paramedics will not know if the baby has already died in utero or will be live born. Paramedics need to be aware that babies born in a residential home or in an ambulance before 28 weeks’ gestation do not have similar survival rates compared with hospital-birth infants, even if resuscitated and transferred to a hospital with a NICU after birth. Paramedics a ending the birth of an extremely preterm baby should consult with a neonatologist from the neonatal emergency retrieval team in their state or area, preferably via the ambulance clinician, to discuss appropriate management of the baby. The diﬃcult ethical decisions about ongoing resuscitation can then be made from a position of more information and in a more controlled environment. Extremely preterm babies have be er prospects for survival and improved quality of survival if they are born at a tertiary perinatal centre with a NICU (Marlow et al., 2014; Boland et al., 2016; Boland et al., 2018). Where possible, women in preterm labour at less than 32 weeks’ gestation should be preferentially transferred to a perinatal centre by the paramedic crew, even if this means bypassing a maternity hospital on route. In most states of Australia and in some areas of New Zealand, this directive is wri en into ambulance service clinical practice guidelines (Stewart et al., 2017). Pathophysiology In the transition from intrauterine life to extrauterine life the fetus undergoes complex physiological, hormonal and cardiovascular changes to survive outside the womb. Most newborns undergo this transition with minimal assistance. Less than 6% of all newborn babies in Australia require assistance to establish eﬀective ventilation at birth and fewer than 0.2% require advanced resuscitation measures to survive (AIHW, 2019). During fetal life, the placenta acts as the gas exchange organ. Oxygen diﬀuses across the placental membrane from the mother's blood to the fetus’ blood. The fetal alveoli are expanded, but are liquid-ﬁlled. Blood ﬂow to the fetal lungs is minimal and the blood vessels perfusing the fetal lungs are constricted. Pulmonary blood ﬂow is low because pulmonary vascular resistance (PVR) is high. Almost 90% of right ventricular output bypasses the lungs and enters the systemic circulation via the ductus arteriosus (see Fig 55.1). The ductus arteriosus connects the main pulmonary artery with the descending aorta, acting as a low-resistance right-to-left shunt between the fetal pulmonary circulation and the systemic circulation (Crossley et al., 2009). Systemic vascular resistance (SVR) is low, primarily because resistance in the placental circulation is low. FIGURE 55.1 Fetal circulation The fetal circulation includes the normal circulatory structures plus the umbilical vein, umbilical arteries, ductus venosus (DV), foramen ovale (FO) and ductus arteriosus (DA). Oxygenated blood travels from the placenta via the umbilical vein, through the DV to the right atrium, where it supplies the heart and brain. Blood is diverted from the high-resistant pulmonary circuit to the low-resistant systemic circuit via the FO and DA. Deoxygenated blood returns to the placenta via the umbilical arteries, which receive 55% of fetal cardiac output. Source: Pairman et al. (2014). Blood from the umbilical vein ﬂows to the inferior vena cava (IVC), across the right atrium to the left atrium via the foramen ovale and from the pulmonary artery into the aorta across the ductus arteriosus. This maintains the brain and myocardium with the most highly oxygenated blood within the fetal circulation. During intrauterine life the fetus is relatively hypoxaemic with a PO2 of 20–25 mmHg (Merrill & Ballard, 2005). Fetal oxygen saturations are approximately 50–60%, but fall to a mean of 40–50% during labour (East et al., 2002). Fetal haemoglobin has a higher aﬃnity for oxygen compared with adult haemoglobin and the fetus has a greater tissue resistance to acidosis. This allows the fetus to compensate for the changes in oxygen consumption and interruption to gas exchange during labour (Merrill & Ballard, 2005). While the fetal circulation is dependent on the placenta for gas exchange, postnatal circulation is reliant on pulmonary gas exchange. The successful transition to pulmonary gas exchange after birth requires clearance of airway liquid and a large decrease in PVR to prevent right ventricular output bypassing the lungs (Crossley et al., 2009). Most newborns will make vigorous eﬀorts to breathe at birth. The pressure created during inspiration causes fetal lung liquid to move out of the alveoli and into the surrounding lung tissue. This can occur in as few as 5– 10 breaths. Lung liquid is cleared from the tissue via the blood vessels and lymphatics. The ﬁrst breaths for a newborn require a much greater negative pressure diﬀerence within the thorax than all subsequent respirations. With the onset of ventilation, oxygen tension rises. There is an eight- to ten-fold increase in blood ﬂow to the lungs due to a large decrease in PVR. The decrease in PVR is mostly due to pulmonary capillary recruitment and relaxation of blood vessels caused by lung aeration and increased oxygen content of the blood. SVR increases in response to loss of the placental circulation, constriction of the umbilical arteries and vein and clamping of the umbilical cord. By 1 minute after birth, with eﬀective breathing and an adequate circulation, the newborn's oxygen saturation of haemoglobin (SpO2) will reach a mean of 66%. By 7–10 minutes after birth, SpO2 will have reached a mean of 90% when measured by pulse oximetry (Dawson et al., 2010a). As PVR decreases and SVR increases, the pressure gradient across the ductus arteriosus reverses, resulting in reverse shunting of blood from left to right into the pulmonary circulation. The foramen ovale (which prior to birth allowed shunting of blood from the right atrium to the left atrium) closes because the pressure gradient reverses. With increased pulmonary blood ﬂow the left atrial pressure rises, eﬀectively closing the foramen ovale. These combined changes, along with biochemical factors (prostaglandins) that control constriction of the smooth muscle of the ductus arteriosus, eventually lead to closure of the fetal cardiovascular shunts. In healthy term infants, functional closure of the ductus arteriosus begins within hours of birth and is complete by 96 hours after birth. The transition from fetal to extrauterine life is then complete. Anatomical closure of the ductus arteriosus usually occurs by 1–2 weeks of postnatal age. In the fullness of time, most people will undergo ﬁbrosis around the valve, eﬀectively sealing it. It is important to note that during the functional stage of ductal closure, any condition causing hypoxia and acidosis in the newborn can result in the ductus reopening (Weisz & McNamara, 2017). This return to a 'fetaltype’ circulation, but without the placental circuit for oxygenation, can lead to life-threatening hypoxia and is not compatible with postnatal life. Infants who are born with critical congenital heart disease (cCHD) are sometimes able to use this patent ductus to allow mixing of oxygenated and deoxygenated blood at the level of the ductus to survive for a short period after birth. They will deteriorate when the duct begins to constrict. This problem may present as an infant who is severely compromised immediately after birth or within hours of birth, or the ﬁrst week of life, depending on whether the anomaly is a cCHD with duct-dependent systemic ﬂow, duct-dependent pulmonary ﬂow or transposition of the great arteries (Khalil et al., 2019). Table 55.1 summarises the diﬀerences in vascular and pulmonary functions in fetal life compared with extrauterine (postnatal) life. Table 55.1 Comparison of vascular and pulmonary functions before and after birth Source: Niermeyer et al. in Gardner et al. (2016). Identifying the newborn at risk of disorders during transition Failure of the newborn to undergo a successful transition to extrauterine life may result from fetal compromise during pregnancy, labour or at the time of birth, or as a consequence of any congenital anomaly that compromises oxygenation. During pregnancy, there are a number of factors associated with a higher risk of problems during transition that potentially require resuscitation intervention at birth (see Box 55.1). BOX 55.1 Factors associated with a higher risk of problems during transition Maternal risk factors Maternal age < 16 or > 35 years No antenatal care Substance abuse Drug therapy (lithium, adrenergic blocking agents, narcotics) Chronic maternal illness (anaemia, congenital heart disease) Diabetes mellitus Maternal infection Prolonged rupture of membranes > 18 hours before birth of the baby Chorioamnionitis (a bacterial infection of the membranes surrounding the fetus: associated with preterm labour) Bleeding during the second trimester of pregnancy Previous stillbirth or neonatal death Fetal risk factors Twins, triplets or higher order multiples Preterm labour (especially less than 35 weeks’ gestation) Post-term birth (after 42 weeks’ gestation) Large for dates (birth weight > 90th centile) Fetal growth restriction (fetal weight < 3rd centile for gestational age) Fetal anaemia or Rh isoimmunisation Polyhydramnios (excessive amniotic ﬂuid) Oligohydramnios (deﬁciency of amniotic ﬂuid) Breech or any other presentation other than cephalic (head down) Reduced fetal movement before the onset of labour Thick meconium in the amniotic ﬂuid Prior to birth and/or during labour, any event that compromises placental function or blood ﬂow through the umbilical cord can lead to fetal hypoxia. The fetus compensates in response to hypoxia by initiating the 'diving reﬂex’ (similar to that seen in diving mammals) to preferentially redistribute blood to the brain, adrenal glands and heart and away from the lungs, liver, spleen, intestines and kidneys (Merrill & Ballard, 2005). The fetus is also capable of switching to anaerobic metabolism, using the glycogen stores in the liver for glycolysis. As most glycogen stores are laid down in the third trimester of pregnancy, preterm babies and growth-restricted babies may not have suﬃcient glycogen stores to maintain anaerobic metabolism for a prolonged period of time. Events that can compromise uterine, placental or umbilical blood ﬂow before and during labour include: antepartum haemorrhage placental abruption cord prolapse cord compression a true knot or a nuchal cord (cord wrapped tightly around the baby's neck) maternal pre-eclampsia or eclampsia. At birth, lung aeration is central to the transition to extrauterine life. If breathing is not established, PVR will remain high and the ductus arteriosus will remain open. Deoxygenated blood will continue to bypass the pulmonary circulation and enter the systemic circulation. The failure of PVR to decrease is known as persistent pulmonary hypertension of the newborn (PPHN). Conditions associated with PPHN include meconium aspiration syndrome, sepsis, pneumonia, asphyxia and respiratory distress syndrome (Weisz & McNamara, 2017). This can progress to a vicious cycle of worsening tissue hypoxia, ischaemia and metabolic acidosis, ultimately causing irreversible organ damage or death. Failure to breathe effectively at birth There are various reasons why a newborn baby may not breathe at birth or fail to breathe eﬀectively despite eﬀorts to do so. These include: respiratory depression secondary to hypoxia (before or during birth) failure to generate suﬃcient pressure during inspiration to force lung liquid from the alveoli and allow air to enter the alveoli: this is more common in very premature babies who have weaker respiratory muscles, a possible lack of surfactant and reduced drive to breathe (Australian and New Zealand Commi ee on Resuscitation [ANZCOR], 2016) the eﬀects of maternal drugs, especially narcotics used within 4 hours of giving birth (including opiates given therapeutically by clinicians) meconium (or blood) blocking the airway structural anomaly aﬀecting the airways (rare). CAUTION! Never administer naloxone to the baby of a mother suspected of using opiates. Naloxone can cause an acute withdrawal and seizures in the newborn. Meconium obstructing the airway Meconium is the ﬁrst faeces passed by the baby and contains amniotic ﬂuid, mucus, lanugo (hair shed from the fetal skin), epithelial cells, bile and water. It is odorous, black or dark green and viscous. If the fetus becomes distressed in utero, it can pass meconium into the amniotic ﬂuid. Placental insuﬃciency (especially in post-term babies), maternal hypertension, pre-eclampsia or maternal drug use can all cause fetal distress in utero. As the fetus becomes more hypoxic, the anal sphincter relaxes and meconium is passed into the amniotic ﬂuid. In response to continued hypoxia, the fetus begins to gasp, leading to inhalation of the meconium into the fetal lungs before birth. This can cause meconium aspiration syndrome after birth—a complex interplay of chemical pneumonitis, surfactant dysfunction and partial or complete obstruction of the airway leading to gas trapping, alveoli collapse and atelectasis (see Fig 55.2). As the disease progresses, the baby becomes increasingly acidotic, hypoxic and hypercapnic and may develop PPHN. Clinically, the baby may have meconium staining (especially of the umbilical cord, skin and ﬁngers) and develop early-onset respiratory distress. FIGURE 55.2 The pathophysiology of meconium aspiration syndrome. Source: Kliegman et al. (2011). Look for! Hyperinﬂated (barrel-shaped) chest Nasal ﬂaring Retraction and recession (in-drawing) of the lower ribs and sternum Respiratory rate > 60 bpm Worsening cyanosis Listen for! Widespread 'wet’ inspiratory crackles The incidence of meconium aspiration syndrome is 1.5 per 1000 births in Australia (Safer Care Victoria, 2018a). Meconium aspiration syndrome is rare in newborns before 34 weeks’ gestation and is more common in term and post-term infants. In a baby who is breech, meconium in the amniotic ﬂuid can be a normal occurrence and does not necessarily indicate fetal distress. Structural anomalies affecting the airways Newborn babies are obligatory nose breathers up to 8 weeks of age. If there is a structural blockage of the airway, a baby will not be able to establish eﬀective breathing. Structural malformations of the airway are very rare. If diagnosed during pregnancy, any plans for a home birth should be abandoned. Although rare, it is important to consider a structural anomaly as a diﬀerential diagnosis in a newborn baby who is making eﬀorts to breathe but remains cyanosed and has limited, unilateral or no chest wall movement. Some of the structural airway anomalies in newborn babies include the following. Choanal atresia. A narrowing or blockage of the nasal airway by tissue or bony cartilage. May be unilateral or bilateral. Incidence: 0.8 per 10,000 births in Australia (Abeywardana & Sullivan, 2008). A pharyngeal airway malformation (e.g. Pierre Robin sequence). Small mandible, cleft palate and a large tongue that falls back into the pharynx obstructing the airway when the baby is lying supine. Incidence: 1.6 per 10,000 births (Consultative Council on Obstetric and Paediatric Mortality and Morbidity, 2017). Diaphragmatic hernia. The abdominal contents (intestines ± the liver) have herniated through a hole in the diaphragm, causing a hypoplastic lung on the aﬀected side. Incidence: 2.5 per 10,000 births in Australia (Abeywardana & Sullivan, 2008). Pneumothorax. May occur spontaneously at birth with the pressures exerted during the ﬁrst breaths of life (incidence: 1–2 per 100 births) or as a result of use of excessive pressure during bag-valvemask (BVM) ventilation. Look for! Persistent cyanosis despite eﬀorts to breathe Nasal ﬂaring Retraction and recession (in-drawing) of the lower ribs and sternum Respiratory rate > 60 bpm Listen for! Decreased or absent breath sounds: unilateral or bilateral Bradycardia (HR < 100 bpm) The newborn with an airway malformation will usually try to make vigorous eﬀorts to inhale air into the lungs, but will become bradycardic and cyanosed as they become increasingly hypoxic. These babies usually have other signs of respiratory distress, such as nasal ﬂaring, intercostal or sub-costal retraction and recession (in-drawing of the ribs) and a respiratory rate above 60 bpm. Providing eﬀective positive pressure ventilation with a BVM may prove challenging in the presence of an airway malformation, even for a paramedic with advanced airway management skills. Failure to establish effective ventilation after birth If a newborn fails to establish eﬀective ventilation after birth, the following will occur: bradycardia (HR < 100 bpm) resulting from lack of oxygen to the myocardium apnoea/further depression of the respiratory drive resulting from lack of oxygen to the brainstem hypotension as a result of hypoxia, bradycardia and poor cardiac contractility; this can be further exacerbated in the presence of hypovolaemia following fetal blood loss and/or shock poor muscle tone secondary to insuﬃcient oxygen delivery to the muscles, brain and other organs central cyanosis (persisting beyond 10 minutes of postnatal age) resulting from hypoxaemia. Unlike adults requiring resuscitation, asystole is extremely rare in newborns. Newborns usually have a healthy myocardium, which is depressed by hypoxaemia rather than vascular disease. Therefore, the key to successful resuscitation of a newborn is eﬀective positive pressure ventilation. Preparing for the birth of a baby Although the need for resuscitation can be anticipated in some instances, there are many times when it is not. Paramedics transporting women in labour and a ending births must have the necessary equipment ready to resuscitate every baby, no ma er how 'low risk’ the mother. Essential equipment for basic newborn resuscitation includes: a warm environment, including warm towels (in a patient's home, towels can be warmed in a tumble dryer, time permi ing; in an ambulance, turn the heating up to 'high’ and close all the doors) a 50 × 50 cm sheet of bubble wrap to place over the newborn after drying (this is extremely eﬀective at maintaining warmth while allowing the paramedic to visualise the baby's breathing eﬀorts) a 28 × 38 cm polyethylene 'zip-lock’ (Glad™) bag with a square hole cut in the end opposite the zip-lock big enough for the baby's head (for newborns < 32 weeks’ gestation or < 1500 g birth weight) a digital thermometer to measure per axilla or rectal temperature a 240-mL self-inﬂating bag (preferably with a positive end expiratory pressure [PEEP] valve, set at 5 cm H2O) face masks: small enough for a preterm baby (35 mm) and a term baby (50 mm) a small oxygen mask (Hudson™) and green Argyle oxygen tubing nasal oxygen cannulae: neonatal size a stethoscope (preferably neonatal size) 8-Fg, 10-Fg and 12-Fg suction catheters a portable suction unit (be aware that most ambulances do not have low-ﬂow suction; the recommended negative suction pressure for clearing the airway of a newborn is 100 mmHg [13 kPa or 133 cm H2O]) a portable oxygen cylinder with a ﬂow meter and tubing, able to deliver a ﬂow of 8–10 L/min oropharyngeal (Guedel™) airways: sizes 00 and 0 (not used routinely in newborns unless there is an airway malformation) two umbilical cord clamps a ﬁrm surface on which to lay the baby supine (in the home, place a warm towel on top of two folded blankets on the ﬂoor near the mother) newborn size 3-lead ECG electrodes ('dots’). Also desirable are: a pulse oximeter with a neonatal sensor, able to be applied to the baby's right hand or right wrist a woollen hat (in the home environment, ask the mother if she has a hat for the baby; if not, a corner of a warm towel will suﬃce). Paramedics with advanced training in airway management (intensive care paramedics) should also carry: endotracheal tubes (ETTs): sizes 2.5 mm, 3.0 mm, 3.5 mm (uncuﬀed) laryngoscope with a straight blade: sizes 0 and 1 end-tidal colorimetric CO2 detector (Pedi-Cap™ is recommended for newborns) laryngeal mask airway: size 1 (for newborns > 2000 g or > 34 weeks’ gestation) intraosseous (IO) needle or IO gun (0.5 mm) tapes for securing endotracheal tube and intraosseous needle adrenaline, 1:10,000 0.9% sodium chloride 10% glucose needles and syringes for drawing up and administering medications. Stress-reliever 'liquorice sticks’ are not recommended as they add signiﬁcant dead space to the ETT and increase the risk of accidental extubation. Cuﬀed ETTs are not recommended for newborns as they can cause serious damage to the airway mucosa (Kezler & Chatburn, 2017). Oropharyngeal (Guedel™) airways are not routinely recommended in newborns as they can cause vagal reactions. An oropharyngeal airway may be useful in a baby with an airway malformation such as Pierre Robin sequence to prevent the baby's large tongue from occluding the airway. CASE STUDY 1: Case 10805, 1435 hrs. Dispatch details A 29-year-old female who is 39 weeks’ pregnant with her third child is in labour. Initial presentation The ambulance crew ﬁnd the patient leaning over her kitchen bench having a strong contraction. She appears to be quite distressed and says she has been having contractions every 2 minutes since she called the ambulance. A neighbour is present and is caring for the patient's other two children. With the next contraction, the patient exhales loudly and groans 'The baby is coming!’ Her membranes rupture and the amniotic ﬂuid is clear. As she kneels on all fours on the ﬂoor, the baby's head is visible between her legs. With the next contraction, the baby is born. The baby girl cries immediately and is moving all her limbs vigorously, but she appears cyanosed. ASSESS Evaluating a newborn's need for assistance during transition begins within seconds of the birth and continues until the transition to extrauterine life is complete. Most newborn babies respond to the stimulation of being born and the cool air of the birth environment by crying lustily. They will move all four limbs and assume a posture of ﬂexion. As they establish regular respirations, their heart rate will rise above 100 bpm within a minute of birth. Newborn babies who are breathing or crying, are ﬂexed or moving their limbs immediately after birth and who have a heart rate above 100 bpm within a minute of birth do not require resuscitation. If these responses are weak, stimulate the baby to breathe by rubbing the baby gently, but briskly, with a towel. Shaking, slapping, spanking or holding a newborn upside-down is potentially dangerous and should never be used as a means of stimulation. PRACTICE TIP A newborn who is ﬂexed and moving their limbs is unlikely to be severely compromised. A newborn who is ﬂoppy, not moving and has an extended posture is likely to require resuscitation. A newborn who is bradycardic at birth with absent or gasping respirations and poor muscle tone (ﬂoppy posture) and who is not moving is more likely to have experienced a signiﬁcant hypoxic ischaemic event before or around the time of birth. This baby will require more than stimulation to establish eﬀective breathing. Dry this baby quickly and prepare to initiate resuscitation. Initial assessment of every newborn baby to determine whether the baby requires more than routine care at birth is based on the following four questions. 1. Is the baby term gestation? 2. Is the amniotic ﬂuid clear of meconium? 3. Is the baby breathing or crying? 4. Is the baby ﬂexed or moving their limbs? If the answer to any of these questions is 'no’, the newborn requires further assessment and initiation of basic life support interventions. These follow a standardised clinical approach. Follow the principles of ensuring that the patient has a clear airway, is breathing and has a circulation, but initiate speciﬁc interventions that are unique to the newborn baby. Patient history At 39 weeks’ gestation, this baby is considered term gestation. The amniotic ﬂuid was clear when the mother's membranes ruptured just prior to the baby being born. Although the paramedics do not have a maternal history other than knowing this is the mother's third baby, the baby's condition at birth will dictate what actions need to be taken to assist the baby during the transition to extrauterine life. Any preexisting medical conditions or complications during pregnancy should still be ascertained, but assessing the baby should be the ﬁrst priority. At birth the baby was crying and moving all four limbs. There was no meconium in the amniotic ﬂuid. Based on this assessment, the paramedics determine she does not require resuscitation. They can treat her as a vigorous (normal) newborn, applying the principles of routine care: ensuring a clear airway providing warmth maintaining ongoing assessment and documentation of the baby's vital signs. Airway A baby's airway is anatomically diﬀerent from that of an adult or older child. Babies have a large head, a short neck and a large tongue. Their tracheal diameter is narrower and their trachea is shorter. The cricoid is the narrowest part of the airway and the larynx is higher and more anterior than that of an adult, at C2–C3 (see Fig 55.3). FIGURE 55.3 The anatomy of the newborn infant. The sagittal sections of the neck of a newborn shortly after birth. Note that in newborns and infants, the neck is shorter and the larynx is located more cephalad. Source: Snell & Smith (1993). To open the airway, position the baby with the head in a neutral or slightly extended position. Avoid both ﬂexion and hyperextension of the head as this can occlude the airway. Most newborn babies will clear their own airway at birth and do not require suctioning. Breathing Uncompromised newborns will normally make vigorous eﬀorts to inhale air into the lungs. Healthy term newborns can exert negative pressures of –80 cm H2O for the ﬁrst breaths to expand the lungs and clear fetal lung ﬂuid (ANZCOR, 2016). After the initial breaths, the pressures exerted are much lower. It is common for newborn babies to pause for a few seconds after these ﬁrst large breaths and then to establish a regular breathing pa ern. A normal respiratory rate in a newborn baby is 40–60 bpm. In the ﬁrst hours after birth, a higher respiratory rate is common, as fetal lung liquid is being cleared. Recession or retraction (in-drawing) of the lower ribs and sternum, or the onset of persistent expiratory grunting, is a sign that the baby is experiencing diﬃculties keeping the lungs expanded. This is most commonly seen in premature babies who lack pulmonary surfactant. It may also be observed in babies with meconium aspiration syndrome and newborns with early-onset sepsis (e.g. Group B streptococcus infection, acquired in utero). Persistent apnoea or gasping respirations, especially in a newborn with poor muscle tone and a heart rate below 100 bpm, is a serious sign. This indicates signiﬁcant compromise. Positive pressure ventilation should be initiated without delay. Cardiovascular With the onset of regular breathing, the newborn's heart rate should rise quickly and should be consistently above 100 bpm within a minute of birth. Some babies will take up to 90 seconds to achieve a heart rate above 100 bpm (Dawson et al., 2010b). Thereafter, the baby's heart rate will vary between 110 and 160 bpm. A heart rate less than 100 bpm in a baby who is not breathing or is breathing inadequately is an indication for positive pressure ventilation. Listening over the apex of the heart with a stethoscope is the best method of assessing the newborn's heart rate at birth. Peripheral and carotid pulses are extremely diﬃcult to feel in newborns. An alternative method is to palpate the base of the umbilical cord while it is still pulsating. However, palpation of the cord is inferior to auscultation as the heart rate tends to be underestimated (Kamlin et al., 2006), potentially resulting in newborn babies receiving interventions they do not require. In paramedic practice, an ECG can be used to continuously measure heart rate if newborn-size 3-lead ECG electrodes are available. Placement of ECG leads in extremely preterm (EP) babies may result in damage to their friable skin. In the absence of a neonatal sensor to monitor heart rate and oxygen saturations, auscultation of the heart rate in EP babies is recommended. Hypovolaemia should be considered in a newborn infant who remains bradycardic despite resuscitation interventions. Clinically, the newborn may be extremely pale, with poor muscle tone (ﬂoppy), with a capillary reﬁll time of > 3 seconds (assessed centrally). If hypovolaemia secondary to blood loss or shock is suspected, the baby will require volume expansion with 10 mL/kg 0.9% sodium chloride, repeated as necessary. This will require insertion of an intraosseous needle, or intravenous cannula, which may be beyond the scope of practice of some paramedics. The normal blood pressure of a term newborn in the ﬁrst hour of life is 70/44 mmHg (mean arterial pressure = 53 mmHg). In a preterm infant, systolic blood pressure varies from 48 to 58 mmHg and diastolic from 24 to 36 mmHg (Safer Care Victoria, 2016). Blood pressure can be measured only with an appropriate-sized newborn cuﬀ, which is not routinely carried by ambulance personnel. Paramedics will have to rely on clinical assessment of perfusion by nonspeciﬁc signs such as capillary reﬁll. Cutting the umbilical cord There is no need to rush to clamp and cut the umbilical cord in a vigorous newborn. The cord can be clamped and cut once it has stopped pulsating (see Ch 54 for more details). Delaying cord clamping for up to 3 minutes after birth is beneﬁcial to babies as it increases their blood pressure and improves iron status during infancy (ANZCOR, 2016). Currently, there is insuﬃcient evidence from human trials to support or refute delaying clamping in a non-vigorous newborn. Immediately after birth the uterine arteries begin to constrict, so gas exchange via the placental circulation cannot be relied upon in a newborn who has failed to establish eﬀective ventilation at birth. In addition, placental function and gas exchange may well have been impaired before birth. In this situation, prompt initiation of resuscitation interventions should take priority over delayed cord clamping (ANZCOR, 2016). Separating the mother and the baby by cu ing the umbilical cord will make it easier for each paramedic to treat one patient, considering there are now two patients. Colour Assessment of colour is a poor proxy for tissue oxygenation in the ﬁrst few minutes after birth in newborn babies (O'Donnell et al., 2007). At 1 minute of postnatal age, a healthy uncompromised newborn will have a mean oxygen saturation of haemoglobin of 60%, hence their cyanosed or 'dusky’ appearance. The oxygen saturations of a healthy newborn will reach a mean of 73% by 2 minutes after birth and can take up to 7–10 minutes to reach a mean of 90% when measured by pulse oximetry (Dawson et al., 2010a). For this reason, colour is not used as part of the initial assessment to identify the newborn requiring more than routine care at birth. It is very common for newborn babies to have acrocyanosis: a blue/purplish discolouration of the hands and feet. This is completely normal in the ﬁrst 24 hours after birth and does not indicate systemic desaturation. No intervention is required. Acrocyanosis is not an indication for oxygen therapy. Persistent central cyanosis, with or without other signs of respiratory distress in a newborn, will require out-of-hospital treatment with oxygen therapy. Extreme pallor that does not resolve with BVM ventilation is a very concerning sign in a newborn. It can indicate severe acidosis and hypotension due to poor cardiac output, with or without hypovolaemia (ANZCOR, 2016). Initial assessment summary Problem Appearance Pulse Grimace Activity Respiratory eﬀort Post-birth management of newborn Initially cyanosed > 100 bpm Crying Moving all limbs Crying and breathing D: There is no environmental danger to the mother, baby or the crew. R: Crying. A: The baby's airway appears clear and there are no visible secretions (blood or meconium). B: The baby is breathing and crying C: The baby's heart rate is > 100 bpm. Although the baby initially appears cyanosed the heart rate and muscle tone are good. While central cyanosis is a critical sign in adults, it is common in newborns in the ﬁrst few minutes after birth. The entire clinical picture needs to be considered. CONFIRM The mother has told the paramedics that she is 39 weeks’ gestation and expecting one baby. Twins would confound this clinical scene. The paramedics would need to call for immediate backup if this mother was giving birth to twins, as then there would be three patients to stabilise and transport. The paramedics have seen that the amniotic ﬂuid is clear of meconium. The baby is crying and has good tone, which would indicate that her heart rate is likely to be above 100 bpm. Although the baby appeared cyanosed at birth, this is a normal ﬁnding in the ﬁrst minute after birth and does not require intervention if the baby is breathing, moving and has a heart rate above 100 bpm. The paramedics perform a set of initial observations on the baby to conﬁrm: Is the baby's heart rate above 100 bpm when auscultated with a stethoscope over the apex? Is the baby continuing to breathe at a rate of 40–60 bpm? Are there any signs of increased work of breathing (nasal ﬂaring, chest recession or expiratory grunting)? Is the baby becoming centrally pink over the ﬁrst minutes after birth (pink gums, mucous membranes and chest)? As they make their initial assessment of the baby, the paramedics need to reassure the mother that her baby looks healthy. She will want to know (or conﬁrm) what sex her baby is and that her baby has no obvious abnormalities. The paramedics should look for any other obvious congenital anomalies of the head, neck, face, limbs, spine and genitalia. The paramedics should note and document the time of birth. They also need to allocate the baby a 1- and a 5-minute Apgar score (see Table 55.2). The Apgar score is not used to guide the resuscitation process: rather, it is assigned retrospectively to summarise the newborn's transition to extrauterine life and to quantify the newborn's response to any resuscitation interventions. Bear in mind that a non-vigorous newborn requires immediate intervention at birth, well before the 1-minute Apgar score is assigned. Conversely, a vigorous newborn can score '0’ for colour at 1 minute, but not require resuscitation. Heart rate is the most important of the ﬁve signs and colour is the least useful (Australian Resuscitation Council, 2016). Initial assessment of the baby is therefore based on assessment of breathing, muscle tone and heart rate. Subsequent assessment is based on breathing, heart rate, muscle tone and colour. Assessment of the baby's temperature is also important before and during transport to hospital to detect hypothermia. (Aim for normothermia: a rectal or per axilla temperature of 36.5–37.5°C.) Use a digital thermometer to assess the baby's temperature. A newborn baby's external auditory canal is usually too small to obtain an accurate temperature using a tympanic membrane thermometer. Table 55.2 Apgar score TREAT Emergency management Safety This baby has been born in her mother's kitchen. If there had been time, it would have been ideal to move the mother to her bed for the birth, then an area on the ﬂoor beside the bed could have been set up with warm blankets and towels to receive the baby. The paramedics needed to be ready to 'catch’ this baby, ideally with warm towels ready, to prevent her from being born onto the cold hard ﬂoor of the kitchen. As a minimum, the crew should have the obstetric kit and newborn BVM ventilation device on hand. Warmth As this baby is vigorous, she should be dried quickly and placed on her mother's chest, skin-to-skin to maintain warmth. A warm blanket should be placed over both of them and a woollen hat (or the corner of a warm towel) placed on the baby's head. This is important as newborn babies can lose heat quickly due to the large surface area of their head. If a baby is not vigorous at birth, they should be placed supine onto warm towels and blankets on the ﬂoor beside the mother (or on the end of the stretcher if in the ambulance). The baby should be dried quickly, especially the head, and the wet towel removed and replaced with a clean warm one. A hat should be placed on the baby's head and a piece of bubble wrap placed over the baby's body, up to the neck, leaving the head exposed. This will allow the paramedics to continue to assess and treat the baby, while maintaining warmth. EVALUATE Continue to assess the newborn. Is the baby breathing eﬀectively? Is the baby's heart rate > 100 bpm? Does the baby have good muscle tone? Is the baby pinking up over the ﬁrst few minutes after birth? If yes, the baby should be nursed skin-to-skin with the mother. If not, the baby will require the next steps of resuscitation: ensuring a clear airway and initiation of positive pressure ventilation if the heart rate is < 100 bpm or the baby is not breathing. Newborn airway management Position to open the airway Position the baby supine with the head in a neutral or slightly extended position. Avoid both ﬂexion and hyperextension of the head as this can occlude the airway. Check if there is obvious blood or secretions in the airway (mouth and nares). Remember that babies are nose breathers, so need clear nares to breathe. Placing a rolled towel or blanket (~5 cm thick) underneath the baby's shoulders can help maintain the baby's head in the neutral position to open the airway. Clear the airway only if necessary Newborns normally do not require suctioning of their mouth, oropharynx or nose at birth: they are able to clear their own airway very eﬀectively. Suctioning can cause more harm than beneﬁt to a newborn and adverse eﬀects include a vagal reaction, resulting in laryngeal spasm, bradycardia and delaying the time to onset of spontaneous breathing (ANZCOR, 2016). Suctioning can also cause damage to soft tissues. If it is required, it should be brief (no more than 5 seconds) and the suction catheter should be passed no more than 5 cm in a term infant. The negative pressure should not exceed 100 mmHg (13 kPa, 133 cm H2O). Most standard suction units in Australian ambulances are not capable of delivering such low negative pressures. The corner of a towel can be used to wipe any secretions from the corner of the mouth and nose in the majority of newborns. Visible blood in the oropharynx or nasopharynx may need to be removed by gently suctioning the mouth, followed by the nose. The mouth is suctioned ﬁrst so that any blood in the pharynx is cleared and cannot be inhaled once the baby's nares are clear and the baby gasps and takes their ﬁrst breath. (Remember that newborn babies are nose breathers.) The baby born through meconium-stained amniotic fluid If the baby is born though meconium-stained amniotic ﬂuid or there is obvious meconium in the mouth or nose, management at birth diﬀers slightly. Ideally, these babies need their airway cleared before being dried and stimulated to breathe. Management of meconium in the airway is dictated by the condition of the baby at birth. If the newborn is vigorous (breathing or crying, good muscle tone and HR > 100 bpm) and there is no obvious meconium in the mouth, suctioning is not indicated. If there is meconium visible in the mouth, suction the oropharynx, followed by the nares (only if necessary). If the baby is not vigorous (not breathing, ﬂaccid and HR < 100 bpm), the aim is to clear the airway before drying and stimulating the baby to breathe. Suction the oropharynx, followed by the nasopharynx (only if necessary). If a paramedic is present at the birth of a non-vigorous baby born through thick meconium-stained ﬂuid, the paramedic may suction the oropharynx under direct vision with a laryngoscope to clear meconium from around the vocal cords. Current evidence regarding suctioning of non-vigorous meconiumexposed infants does not either support or refute the practice. Suction under direct vision should not be performed if the baby has already cried or has established ventilation, as this can further compromise the baby and does not alter the outcome in terms of developing meconium aspiration syndrome (ANZCOR, 2016). Having cleared the airway and positioned the baby to open the airway, reassess the baby. Positive pressure ventilation Positive pressure ventilation with a BVM is indicated if: the baby is not breathing the baby has gasping respirations (a serious sign indicating neurological compromise secondary to asphyxia) the heart rate is less than 100 bpm after drying and stimulating the baby to breathe. Face-mask placement The face mask should be large enough to cover the baby's nose and mouth without covering the eyes or overlapping the chin. Paramedics need to carry a range of sizes of face masks for term (50 mm) and preterm (35 mm) babies. A face mask with a cushioned rim is preferable to a mask without a rim (ANZCOR, 2016). Face-mask leaks up to 60% are common and can impede eﬀective BVM ventilation (Wood et al., 2008). Just because the mask ﬁts does not mean the seal is adequate. Improvement in the baby's heart rate is the most important indication that BVM ventilation is eﬀective. If the heart rate is not improving, ensure the airway is clear, then reapply the mask and try to improve the seal. 240-mL bag vs 600-mL bag A 240-mL BVM should ideally be used to ventilate a newborn baby of any birth weight. (See the infant self-inﬂating bag in Fig 55.4.) This is because the tidal volume of a newborn is approximately 5–10 mL/kg body weight (ANZCOR, 2016). If chest rise is not achieved with a 240-mL bag, it is most likely because there is a large leak between the face and the mask. Ensure the airway is clear: brieﬂy suction the oropharynx to clear any secretions and reposition the head in a neutral position. Try reapplying the mask to improve the seal. FIGURE 55.4 Comparison of disposable self-inflating bags with PEEP valve for BVM ventilation: adult: 1500 mL; paediatric: 600 mL; infant: 240 mL (recommended size for newborn babies). Source: Image provided courtesy of Laerdal. The technique for mask ventilation The paramedic should position themself directly behind the baby's head. With the baby's head in a neutral or slightly extended (‘sniﬃng’) position, roll the mask onto the baby's face from the chin upwards and over the mouth and nose. Using the thumb and index ﬁnger, hold the mask by the outer rim, applying equal downward pressure on the mask. Using the third ﬁnger of the same hand, apply an equal amount of jaw lift upwards. Do not hyperextend the head, as this will occlude the airway. Commence BVM ventilation at a rate of 40–60 breaths per minute. Count ‘breathe two three, breathe two three, breathe two three’ as you squeeze and release the bag. Peak inﬂating pressures required for initial breaths to open the lungs and for subsequent breaths are variable and inﬂuenced by gestational age, mode of birth and underlying lung disease. If available, it is ideal to use a device that allows the peak inspiratory pressure (PIP) and positive end expiratory pressure (PEEP) to pre-set (e.g. a T-piece device—NeoPuﬀ™ or similar). T-piece devices are usually only available in hospital se ings and are routinely carried by dedicated neonatal retrieval teams. In term newborns, start with an initial PIP of 30 cm H2O. In very preterm babies born < 32 weeks’ gestation, start with an initial PIP of 20–25 cm H2O. If you are in an ambulance se ing and unable to measure the PIP, squeeze the bag just hard enough so that the chest and upper abdomen move slightly. The chest wall movement should be equal to that seen in normal quiet breathing (ANZCOR, 2016). Avoid delivering excessive pressures and volumes, especially if using a 600-mL paediatric bag. This may lead to overdistension of the alveoli, causing a pneumothorax. Immature preterm lungs can also be damaged from delivery of high tidal volumes, even with a 240-mL bag (Björklund et al., 1997). If a PEEP valve is a ached to the bag, set it to 5 cm H2O. PEEP assists preterm newborn babies to establish and maintain functional residual capacity; it also helps improve their oxygenation (Siew et al., 2009). Most newborn babies respond very quickly to eﬀective positive pressure ventilation. When performed correctly, this will result in a rapid improvement in heart rate, usually without the administration of supplementary oxygen (ANZCOR, 2016). Once it is clear the baby is responding to BVM ventilation, as evidenced by an improvement in heart rate, the PIP and ventilation rate can and should be reduced (ANZCOR, 2016). Mouth-to-mouth-and-nose resuscitation If a 240-mL or 600-mL bag is not available, rescue breathing by mouth-tomouth-and-nose ventilation should be used. The paramedic should apply their mouth over the baby's mouth and nose and give small inﬂations at a rate of 40–60 breaths per minute (~1 breath per second). Aim to achieve a visible rise and fall of the chest. Continue until the baby's heart rate increases to above 100 bpm and the baby is breathing spontaneously. Air or oxygen for resuscitation Newborn babies requiring BVM ventilation should initially be resuscitated with air (21% oxygen). High-ﬂow 100% oxygen should be reserved for those severely compromised newborns who do not respond to resuscitation eﬀorts within the ﬁrst minutes of life. Level 1 evidence from randomised controlled trials comparing initiating resuscitation with air (21% oxygen) versus 100% oxygen in newborns consistently demonstrates a signiﬁcant reduction in mortality when air is used (Davis et al., 2004). In term newborns, the use of 100% oxygen has also been shown to delay the time taken by the newborn to initiate breathing or crying (Vento et al., 2001). Newborn babies, especially premature babies, can become rapidly and dangerously hyperoxic when exposed to 100% oxygen. There is increasing evidence that even brief exposure to excessive oxygenation can be harmful to the newborn baby, both during and after resuscitation. Use of 100% oxygen reduces cerebral perfusion in newborn babies (Davis et al., 2004) and enhances oxidative stress for up to 4 weeks after birth (Vento et al., 2001, 2002; Perlman et al., 2010). Pulse oximetry is used routinely at in-hospital births to guide supplemental oxygen administration. To avoid hyperoxia, the oxygen concentration is reduced once the newborn's SpO2 is above 90%. The aim of supplemental oxygen administration is to achieve the normal rise of SpO) over the ﬁrst minutes of life seen in healthy term infants. The pre-ductal target saturations for newborn babies during the ﬁrst minutes after birth are shown in Table 55.3. A neonatal sensor is required to measure oxygen saturations. The sensor should be placed onto the baby's right hand or right wrist to obtain pre-ductal readings of SpO2. The preductal saturations reﬂect brainstem oxygen delivery and have be er perfusion and oxygenation than post-ductal saturations from the left hand, left foot or right foot (Mariani et al., 2007). As long as there is adequate cardiac output and peripheral blood ﬂow for the oximeter to detect a pulse, the oximeter will display a continual measurement of heart rate and SpO2, both of which are extremely useful during resuscitation of a newborn baby. Table 55.3 Target pre-ductal* saturations for newborn babies during resuscitation Time from birth (in minutes) 1 minute 2 minutes 3 minutes 4 minutes 5 minutes 10 minutes Target pre-ductal saturations for newborn babies during resuscitation 60–70% 65–85% 70–90% 75–90% 80–90% 85–90% * Pre-ductal saturations are obtained by placement of the pulse oximeter probe on the infant's right hand or right wrist. All other limbs are post-ductal. Source: ANZCOR (2016). If paramedics do not have access to a neonatal sensor and therefore cannot measure the baby's SpO2, the following principles apply with regard to the use of supplemental oxygen for newborn resuscitation. Normal healthy newborns are cyanosed or dusky at birth and take several minutes to 'pink up’. If they are breathing or crying, with a heart rate above 100 bpm, they do not require supplemental oxygen. Visual assessment of the presence or absence of cyanosis has poor correlation to the baby's PaO2 and SpO2. The only absolute indication for the administration of 100% highﬂow oxygen during resuscitation is if the newborn has a heart rate less than 60 bpm after at least 30 seconds of eﬀective BVM ventilation in air. If the heart rate is between 60 and 100 bpm and the baby is breathing ineﬀectively, 100% oxygen can be used brieﬂy until the heart rate improves to above 100 bpm. If the baby remains persistently centrally cyanosed and/or has signs of respiratory distress (respiratory rate greater than 60 bpm, nasal ﬂaring, retraction or recession, cyanosis), the paramedics should consult with the neonatal emergency retrieval service via the ambulance clinician regarding management. Some babies will require intubation and positive pressure ventilation, while others may be safe to transport self-ventilating with 2 L of oxygen delivered by nasal cannulae or a Hudson™ face mask. Chest compressions A newborn baby who has suﬀered signiﬁcant peripartum hypoxic ischaemia, with or without an associated acute sentinel event (e.g. placental abruption or antepartum haemorrhage), may present in circulatory collapse with poor cardiac output and may not respond to positive pressure ventilation. Asystole at birth or after birth is rare. Remember: fewer than 2 per 1000 live born babies in Australia require chest compressions at birth (AIHW, 2019). Even if the heart rate is less than 60 bpm at birth, at least 30 seconds of eﬀective BVM ventilation should be performed before chest compressions are initiated. This diﬀers from adults, where compressions are commenced as soon as possible in the absence of a palpable pulse. A heart rate less than 60 bpm and performing chest compressions are an absolute indication for the use of 100% high-ﬂow oxygen via the BVM. PRACTICE TIP Newborn babies usually have a healthy myocardium, which is depressed by hypoxaemia. Eﬀective ventilation is the key to resuscitation. Technique In newborns, the two-thumb, hand-encircling technique (see Fig 55.5A) is the preferred option. Using this technique, both thumbs are superimposed on one another or placed side by side on the lower third of the sternum (just below the nipples), with the hands encircling the newborn's torso. The chest should be compressed one-third of the anterior–posterior diameter. This technique has been shown to have advantages over the two-ﬁnger technique (see Fig 55.5B) because it: FIGURE 55.5 A The two-thumb, hand-encircling technique (recommended). B The two-finger technique. Source: Niermeyer et al. (2016). PRACTICE TIP Signs of eﬀective BVM ventilation include: improvement in the heart rate above 100 bpm a slight rise of the chest and upper abdomen improvement in oxygenation (SpO2 and/or colour). improves peak systolic and coronary perfusion pressure results in more consistent depth of compressions over prolonged periods of time is easier to perform and less tiring compared with the two-ﬁnger technique (ANZCOR, 2016). The ratio of compressions to inflation In the newborn, the ratio of compressions to BVM inﬂation is 3 : 1, providing a higher rate of inﬂation than a 15 : 2 ratio (ANZCOR, 2016). This ratio is used for both one- and two-person resuscitation teams. The aim is to achieve 90 compressions and 30 inﬂations per minute (2 events per second, 120 events per minute). Count 'One two three breathe, one two three breathe’ as you compress, compress, compress, inﬂate; compress, compress, compress, inﬂate. The compressions should be paused while the positive pressure inﬂation is delivered (unless the baby has been intubated, in which case there is no need to pause compressions to deliver the positive pressure inﬂation via the ETT). The baby's chest should fully expand between compressions, but the paramedic's hands should not move from their position around the baby's torso. Chest compressions should be delivered for at least 30 seconds with minimal interruption before checking the heart rate again. If a pulse oximeter is providing a continuous reading of heart rate and oxygen saturations, this is evidence of eﬀective output. Ongoing management Paramedics with appropriate training may perform these procedures in the out-of-hospital environment: insertion of a laryngeal mask airway (LMA) in babies > 2000 g or > 34 weeks’ gestation intravenous or intraosseous (IO) access medication and ﬂuid administration. Intubation Intubation is appropriate in the following out-of-hospital situations: the baby's heart rate is not improving with BVM ventilation the baby is born through meconium and is not vigorous at birth the baby is extremely premature (< 28 weeks’ gestation, < 1000 g birth weight) the baby is born without a detectable heart rate. The heart rate should improve following intubation with eﬀective delivery of positive pressure ventilation. See Table 55.4 for the appropriate endotracheal tube sizes. Table 55.4 Selecting the correct size endotracheal tube * Weight in kg + 6 cm can be used to estimate the depth of insertion for babies > 1 kg birth weight. Insertion of an LMA If intubation is impossible or not feasible, or the provider is not trained in neonatal intubation, a size 1 LMA may be used to secure an airway in a newborn > 2000 g or > 34 weeks’ gestation. The ANZCOR guidelines (2016) state an LMA should be considered as an alternative to tracheal intubation if face-mask ventilation is unsuccessful and tracheal intubation is unsuccessful or not feasible (ANZCOR, 2016). Intravenous or IO access Since so few babies require the administration of drugs following birth, paramedics will most likely be unfamiliar with gaining access to the intravascular space. Compared with adults, using IO devices may be faster and more reliable. The IO route is quickly becoming the preferred method of establishing access in the out-of-hospital environment. The preferred site is the proximal tibia. Aim to enter a few centimetres below the tibial tuberosity at the centre of the ﬂat anteromedial surface. Direct the needle caudally away from the upper tibial epiphysis (Safer Care Victoria, 2018b). The distal anterolateral surface of the tibia is an alternative site. The distal femur and sternum should not be used in babies (Safer Care Victoria, 2018b). An 18-gauge IO needle is preferable to using an IO gun in a premature baby (ANZCOR, 2016). An IO gun should be used with extreme caution in a premature baby, especially one weighing less than 1500 g due to the fragility of the baby's small bones and the small IO space. Umbilical venous catheterisation (UVC) is not a supported procedure in paramedic practice. There is a risk of cannulating the umbilical artery and inadvertently administering vasoactive drugs into the artery (e.g. adrenaline). Complications include bleeding, infection, perforation, clot formation, cardiac arrhythmias, hepatic necrosis and portal hypertension (Safer Care Victoria, 2018c). Peripheral cannulation (IV) is extremely diﬃcult in a newborn who is shocked or collapsed. Since it is also timeconsuming it is be er to proceed with patient transport. Medications and fluid administration The priority during advanced resuscitation of a newborn baby is to ensure that the continuity and technique of external chest compressions and positive pressure ventilation is not compromised. However, if external chest compressions with positive pressure ventilation in 100% oxygen fail to restore the heart rate and circulation, then adrenaline may be required. Adrenaline is indicated if the heart rate is below 60 bpm after at least 30 seconds of external chest compressions with BVM ventilation in 100% oxygen (and at least 30 seconds of eﬀective BVM ventilation in air before external cardiac compressions are commenced). Adrenaline should preferably be administered intravenously (ANZCOR, 2016). Inserting a peripheral line in a shocked or collapsed newborn is extremely diﬃcult. An IO needle can be used as an alternative if there is no IV access (ANZCOR, 2016). There is insuﬃcient evidence for use of the endotracheal adrenaline, as the safety and eﬃcacy of the endotracheal dose has not been studied in human neonates. If the endotracheal route is used, ANZCOR state that it is likely that a higher dose will be required to achieve the desired eﬀect. If the tracheal route is used, up to 10 times the IV dose (50– 100 microgram/kg) should be used (ANZCOR, 2016). Volume expanders may be indicated in a baby in whom hypovolaemia secondary to fetal blood loss or septic shock is suspected. Normal saline is the volume expander of choice in the out-of-hospital se ing—0.9% sodium chloride for volume expansion is indicated if: blood loss is suspected and the baby appears shocked the baby appears very pale, capillary reﬁll > 4 seconds, perfusion is poor femoral pulses are weak the baby is not responding to resuscitation measures with an improvement in heart rate. Consideration should be given to preventing and treating hypoglycaemia in all babies, especially those who have required resuscitation at birth. Adverse neurological outcomes have been demonstrated in newborns with hypoglycaemia following a hypoxic ischaemic insult (Salhab et al., 2004). Although the optimal range of blood glucose concentration to minimise brain injury is still to be deﬁned, aim to maintain the baby's blood glucose level ≥ 2.5 mmol/L (ANZCOR, 2016). IM glucagon can be administered if IV or IO access is not available for a continuous 10% glucose infusion. Glucagon acts by mobilising glycogen from the liver. If the baby has inadequate stores of glycogen (e.g. extremely preterm baby or growth-restricted baby), glucagon treatment may not be as eﬀective. The following drugs are not indicated in newborn resuscitation. Lignocaine, atropine, calcium, magnesium, potassium, vasopressin and amiodarone are not indicated in the resuscitation of a newborn baby at any time. Sodium bicarbonate. Level 1 evidence from two human trials has failed to demonstrate a beneﬁcial impact on survival, neurological outcome or acid—base balance in asphyxiated babies (Lokesh et al., 2004; Murki et al., 2004t. The known side eﬀects include depressed myocardial function, exacerbation of intracellular hypercarbia, paradoxical intracellular acidosis, reduced cerebral blood ﬂow and increased risk of intraventricular haemorrhage in preterm babies. Naloxone. This is not indicated in initial newborn resuscitation as there is no evidence of beneﬁt and substantial evidence of risk (myocardial depression, cardiac arrhythmias, exacerbation of cerebral white-ma er neuro-histological injury; Van Woerkom et al., 2004). The ﬁrst priority is to provide BVM ventilation if the baby is not breathing. If there is any suspicion that the mother is an intravenous drug user, naloxone is absolutely contraindicated in the baby, as it can cause an acute withdrawal and seizures. Documentation The paramedics should document the following whenever a birth occurs in the out-of-hospital se ing: time of birth (this is not always possible if the birth occurred prior to the paramedics’ arrival) time of ﬁrst spontaneous breath resuscitation interventions, timing and response (including BVM ventilation, use of 100% oxygen, external chest compressions, adrenaline or sodium chloride administration) heart rate, respiratory rate, respiratory eﬀort, perfusion, tone and colour every 15 minutes during transport temperature (per axilla or rectal) blood glucose level (if possible) Apgar score at 1 and 5 minutes (and assessed every 5 minutes until the score is 7 or greater). Birth during transport Delivering a baby during transport adds a layer of complexity to the care of both mother and baby. Space (or lack thereof) is a signiﬁcant issue. This will be a highly emotional and potentially chaotic situation, even if the baby is born in a healthy condition. If the baby requires resuscitation, this will have to be performed on the end of the stretcher at the mother's feet, in her full view. Even if the mother has a support person with her in the ambulance, that person will need to sit in the front passenger seat to give the paramedics room to work in the rear of the ambulance. All aspects of resuscitation and subsequent care of the baby are further complicated by the limitations of suitable equipment for sick newborns in the out-ofhospital environment, including monitoring equipment, umbilical catheters for intravenous access, an incubator for thermoregulation and assisted ventilation devices. If the mother experiences complications during the birth (e.g. shoulder dystocia) or following the birth (e.g. postpartum haemorrhage), the paramedics will be further stretched. Backup assistance from a second crew is highly desirable if the birth is complicated or the baby is premature or compromised. Where possible, mother and baby should not be separated and each should have their own paramedic, but this may not be possible in some rural and remote areas. Ideally, a paramedic from the second crew can drive the ambulance while the two paramedics from the ﬁrst crew care for the mother and her baby. Paramedics are strongly advised to consult with a neonatologist from their local Newborn and Paediatric Emergency Transport Service or equivalent regarding ongoing emergency management of any baby requiring resuscitation and for all premature babies. The consultant can direct the paramedic crew to the most appropriate receiving hospital, which may not necessarily be the closest hospital, en route. The consultant may also activate a neonatal team to proceed to the receiving hospital to continue management of the baby and to transfer the baby to a tertiary hospital with a NICU. There will be times when a baby is too premature or too severely asphyxiated to survive, despite the best eﬀorts of the paramedics. If a baby has been stillborn or has died despite resuscitation eﬀorts, the paramedics will ﬁnd themselves in one of the most diﬃcult situations they will face in their career. The death of a baby is devastating for all involved. Encourage the mother (and father, if he is present) to see their baby and allow one of the parents to hold the baby during transport to hospital if they wish. The hospital will arrange for SANDS (the Stillbirth and Neonatal Death Support Association) to contact the parents and oﬀer counselling to the family. It is equally important that the paramedics are provided with an opportunity to debrief and receive counselling following the death of a baby in their care. Discontinuing resuscitation The Australian Resuscitation Council guidelines and international guidelines state that it is reasonable to discontinue resuscitation of a newborn baby if there is no measurable heart rate after 10 minutes of maximal resuscitation (ANZCOR, 2016). Both survival and quality of survival deteriorate rapidly beyond this time and there is a very high risk of severe neurological disability if the baby does survive (Casalaz et al., 1998; Haddad et al., 2000). Where early death is inevitable, resuscitation is not indicated. This may be the case in babies born at the limits of viability (22–23 weeks’ gestation) and those with known congenital anomalies that are incompatible with life (Lantos et al., 1988). The decision to withdraw or not to initiate resuscitation eﬀorts is not an easy one. Where possible, this should be made in a hospital environment in consultation with the parents, who may have strong views on an acceptable risk of morbidity. Hospital admission On admission to the neonatal intensive or special care nursery, the following procedures are standard care for sick and/or premature babies: continuous cardiorespiratory, blood pressure, temperature and SpO2 monitoring intubation and mechanical ventilation (or nasal continuous positive airway pressure [CPAP]) intratracheal surfactant administration (to treat respiratory distress syndrome) frequent blood gas analysis during the acute stage of illness umbilical venous catheterisation (UVC) and umbilical arterial catheterisation (UAC) IV penicillin and gentamicin (for all babies with respiratory distress until blood cultures show no growth); aciclovir may be added if a viral herpes simplex virus infection is suspected (e.g. the mother has an active herpes lesion) IV therapy with 10% glucose at 60 mL/kg/day (day 1) volume expansion with 0.9% sodium chloride to treat hypovolaemia and metabolic acidosis inotropes (dopamine or dobutamine) to treat hypotension incubator care for thermoregulation therapeutic hypothermia (for babies with grade 2 or grade 3 hypoxic ischaemic encephalopathy [HIE]) other imaging (head ultrasound to detect intraventricular haemorrhage in preterm babies; magnetic resonance imaging [MRI] to detect brain injury in babies with HIE). Investigations The following investigations and monitoring may be performed at the receiving hospital to diagnose and treat the underlying condition that has contributed to abnormal transition to extrauterine life: chest x-ray to diagnose respiratory distress syndrome, pneumonia, pneumothorax or meconium aspiration syndrome blood gas analysis including lactate to diagnose respiratory failure and/or metabolic acidosis urea and electrolytes to guide IV ﬂuid replacement therapy full blood count, C-reactive protein, IT ratio and blood cultures to rule out infection blood glucose level to diagnose and treat hypoglycaemia continuous blood pressure monitoring via the UAC or peripheral arterial line to detect hypotension and guide the concentration of inotrope infusions continuous cardiorespiratory, SpO2 and temperature monitoring to monitor cardiorespiratory stability and to guide supplemental oxygen therapy. Follow-up The baby's length of stay in hospital will vary according to gestational age and severity of illness. A healthy term infant born before arrival at hospital who was vigorous at birth would normally room in with their mother in the postnatal ward after a short period of observation in the special care nursery. The average length of stay for these babies is 2–4 days. The baby will receive a routine follow-up visit from the local maternal child health nurse within a week of discharge. A preterm baby born at 24 weeks’ gestation will be in hospital for 12–16 weeks on average. Those who develop chronic lung disease may be hospitalised for many weeks or even months beyond the term-corrected age. Extremely premature babies may be discharged home from hospital on low-ﬂow oxygen therapy. Many require readmission for respiratory illnesses such as bronchiolitis during the ﬁrst 6–12 months of life. A term baby whose birth is complicated by meconium aspiration syndrome will usually require mechanical ventilation for a period of 4–12 days with high peak inspiratory pressures (30–35 cm H2O). These babies often require deep sedation, muscle relaxation and inhaled nitric oxide (iNO) while ventilated. PPHN often complicates severe cases of meconium aspiration syndrome (Safer Care Victoria, 2018a; Weisz & McNamara, 2017). Length of stay will vary according to the severity of the disease. A baby with HIE secondary to peripartum hypoxia may or may not require mechanical ventilation. Babies with grade 1 (mild) HIE do not usually require ventilation, whereas a baby with grade 2 (moderate) or grade 3 (severe) HIE who is experiencing seizure activity is likely to be intubated and ventilated to protect the airway. As these babies do not usually have parenchymal lung disease (unless complicated by meconium aspiration syndrome) they usually require low ventilation pressures and slow rates. They may require inotropes to support cardiac output and blood pressure. Therapeutic hypothermia (deep body cooling to 33–34°C) is commenced for neuroprotection for babies ≥ 35 weeks’ gestation with grade 2 or 3 HIE (Safer Care Victoria, 2018d). Length of stay varies according to the severity of HIE and ischaemic eﬀects on other organs (brain, kidneys and myocardium). Treatment may be redirected to palliative care for babies with grade 3 HIE if MRI reveals extensive and irreversible brain damage. CASE STUDY 2: Case 10407, 1755 hrs. Dispatch details A 25-year-old female who is 26 weeks’ pregnant has ruptured her membranes and is having contractions. Initial presentation The paramedics are met in the front drive of the house by the woman's partner. He is yelling, 'Quick, quick, she's had the baby!’ He takes them to the bathroom where the woman is si ing on the ﬂoor holding a tiny newborn baby in her arms wrapped in a bath towel. The preterm baby All preterm babies, but especially those born before 28 weeks’ gestation or weighing less than 1500 g at birth, become hypothermic very easily. Heat loss will be further exacerbated when birth occurs in an out-of-hospital se ing, as paramedics have limited control over the temperature of the birth and transport environment. The Australian and New Zealand Commi ee on Resuscitation (2016) neonatal resuscitation guidelines recommend using a polyethylene (foodgrade, heat-resistant) zip-lock bag as a means of preventing extreme heat loss in very premature babies. The use of a polyethylene bag to prevent hypothermia is an evidence-based practice, used in hospitals routinely since 2006 for babies born before 32 weeks’ gestation or weighing less than 1500 g at birth. To prepare the bag, cut a square hole just large enough for the baby's head to pass through the bag at the opposite end to the zip-lock. At birth, place the baby immediately, without drying (i.e. wet and warm) into the bag with the body completely covered and just the head exposed through the hole at the top. Then lock the bag under the baby's feet. Dry the baby's head and place a hat on it. If the baby is breathing and has a heart rate above 100 bpm, the baby can be placed onto the mothers chest (skin-to-skin) and a warm blanket placed over the top of the two of them. If the baby requires resuscitation interventions, place the baby into a bag and cover with a warm towel and warm blankets next to the mother. Leave the baby in the bag with just their head out and cover the baby with a space blanket or warm towels. Ensure the baby has a hat or warm towels covering their head. If the baby has already been born when the paramedics arrive on the scene, the baby will inevitably be hypothermic. The baby should be dried well and a hat placed on their head. A polyethylene bag can still be used as long as the paramedics are able to provide a radiant heat source directly onto the bag or warm blankets around the bag. During transport to hospital, if no incubator is available and if safe to do so, baby can be placed skin-to-skin with the mother, as her body temperature will maintain the baby's temperature far more eﬀectively than using space blankets or warm blankets. Hypothermia increases both mortality and morbidity, especially in very preterm babies. Preventing hypothermia is one of the most diﬃcult challenges faced by paramedics in the out-of-hospital se ing, for both term and preterm babies. ASSESS It might seem logical to ask the mother ‘When was your baby due?’ However, if the mother responds with a date that is several months away, it is somewhat challenging to calculate how preterm the baby is. When assessing any pregnant woman or her newborn baby, it is be er to ask, ‘How many weeks pregnant are you?’ The crew may also ask the woman or her partner the following. How long ago was the baby born? Did the baby cry and move immediately after birth? Are you expecting more than one baby? Have you been well during your pregnancy? 1809 hrs Primary survey: The baby is wet and is still a ached to the umbilical cord. She looks to be approximately 600–800 g. She is making some weak crying noises and moving her arms and legs. 1810 hrs Pertinent hx: The mother informs the crew that the baby cried as soon as she was born and was moving all her limbs. This is the mother's third baby. Her previous baby was also born preterm at 31 weeks’ gestation. 1811 hrs Assessment: The baby is breathing rapidly but has marked intercostal chest recession. Her head is still wet. Her colour is pale. The umbilical cord is no longer pulsating. 1812 hrs Vital signs survey: Perfusion status: HR 150 bpm (auscultation), skin slightly centrally cyanosed, capillary reﬁll > 4 seconds, temperature 34.6°C (per axilla). Respiratory status: 88 bpm, equal air entry bilaterally, nasal ﬂaring and grunting with each breath, marked intercostal and substernal retraction. Conscious state: The baby has her eyes closed. She is lying in an extended posture. CONFIRM In many cases paramedics are presented with a complex situation involving more than one patient. A critical step in the treatment plan is to determine who should receive priority in this situation. The mother is conscious with no obvious haemorrhage but the newborn is clearly extremely preterm and is unable to breathe eﬀectively. The paramedics’ visual assessment conﬁrms that the baby is experiencing the problems associated with preterm birth that they anticipated. Assess! Is the newborn crying or breathing? Is the heart rate above 100 bpm? Does the newborn have good muscle tone? Are there obvious secretions in the mouth or nose? TREAT Emergency management The ﬁrst priority for the paramedics is to move this mother and her baby to a safer, warmer place than a cold bathroom ﬂoor. Simultaneously, they need to rapidly assess the baby's heart rate, work of breathing, tone and oxygenation (if possible). They also need to call for backup from an intensive care paramedic crew, as it is highly likely that this baby will require respiratory support before transport to hospital. At 26 weeks’ gestation, early-onset respiratory distress and respiratory failure are inevitable. Preterm babies have the following anatomical and functional problems that result in an inability to support ventilation and oxygenation: underdeveloped alveolar saccules with limited surface area for gas exchange lack of pulmonary surfactant so alveoli collapse on expiration and functional residual capacity (FRC) is not established low compliance in the lung (small changes in volume in response to application of high pressures). The lack of surfactant and decreased lung compliance lead to increased work of breathing, fatigue, atelectasis and a ventilation/perfusion (V/Q) mismatch (Gardner et al., 2016). Clinically the baby will be tachypnoeic (respiratory rate > 60 bpm), with grunting, nasal ﬂaring and chest recession, and may be centrally cyanosed. One paramedic clamps and cuts the umbilical cord while the other prepares an area in the bedroom to treat the baby. Having laid down a warm towel on top of two blankets, the paramedic cuts a hole in a 28 × 38 cm zip-lock bag. The baby is quickly carried into the bedroom and laid supine on the warm towel, dried and then placed with her body completely in the bag and her head outside of the bag. The paramedic zip locks the bag at the bo om and places a warm blanket over the bag. He dries the baby's head and uses a corner of a second towel to cover the top of her head. 1822 hrs: Perfusion status: HR 90 bpm (auscultation), skin slightly centrally cyanosed. Respiratory status: No respiratory eﬀort. Conscious state: The baby has her eyes closed and has poor muscle tone (ﬂoppy). 1826 hrs: The paramedics commence BVM ventilation at a rate of 60 bpm. This rate is appropriate for a baby of 26 weeks’ gestation with respiratory distress as she is likely to be hypercapnic. Her heart rate improves quickly with BVM ventilation to 130 bpm, but she remains cyanosed. As her colour is not improving and she has signs of marked respiratory distress, the paramedics BVM ventilate her using 100% oxygen. If the respiratory distress remains severe, intubation should be considered according to local guidelines and the baby ventilated at 60 bpm, aiming for a tidal volume of 4–6 mL/kg. The insertion of a UVC is not supported in paramedic practice. The risk of haemorrhage, inadvertent cannulation of the umbilical artery, drug or ﬂuid administration into the artery, air embolism and infection are too great. While insertion of an IO needle is easier and quicker than peripheral venous cannulation of a newborn baby in the out-of-hospital se ing, there is no IO needle small enough to safely cannulate a baby of 26 weeks’ gestation (Safer Care Victoria, 2018b). The crew will not be able to gain IV access on this baby. Furthermore, such a procedure would only delay transport to hospital, which is a priority in this case. EVALUATE Umbilical venous and arterial lines were inserted in hospital. A chest x-ray revealed respiratory distress syndrome. Surfactant replacement therapy was given intra-tracheally, maintenance ﬂuids of 10% glucose were commenced, and IV penicillin and gentamicin were given for 7 days. A dobutamine infusion was also required to treat hypotension. The baby required high-frequency ventilation for 14 days and then extubation to nasal CPAP and then to high-ﬂow nasal canulae (HFNC). She remained on HFNC for a further few weeks. She was discharged home after 14 weeks on low-ﬂow oxygen of 100 mL/min. Long-term role Complications of prematurity and peripartum asphyxia can have lifelong eﬀects. Extremely low birth weight babies (500–999 g birth weight) have increased rates of adverse neurodevelopmental outcomes such as cerebral palsy, deafness, blindness and severe developmental delay (Doyle et al., 2011). The rates of disability increase with decreasing gestational age. CASE STUDY 3: Case 10306, 0430 hrs. Dispatch details A 26-year-old female who is 41 weeks’ pregnant is in labour for a planned home birth. There is thick meconium in the amniotic ﬂuid. The midwife assisting with the home birth has requested transport to hospital. Initial presentation The paramedics are met by the woman's husband. He takes them into the lounge room where they ﬁnd the woman on all fours over a ﬁt ball. The midwife is listening to the fetal heart rate with a fetal Doppler monitor. ASSESS 0444 hrs Primary survey: The woman is alert. She has just had a strong contraction lasting 1 minute. The fetal heart rate was 80 bpm during and for 30 seconds after the contraction. 0445 hrs Chief complaint: The midwife shows the crew a sanitary pad covered in thick meconium. 0446 hrs Pertinent hx: The midwife informs the crew that the woman was 8 cm dilated when she performed a vaginal examination (VE) 15 minutes ago. During the VE, the membranes ruptured and meconium was seen in the amniotic ﬂuid. The woman is 41 weeks and two days pregnant. This is her ﬁrst pregnancy. The woman has been in labour for 12 hours. If this baby is breech, this could explain the meconium in the amniotic ﬂuid. Meconium in a breech baby can be a normal ﬁnding that is not necessarily indicative of fetal distress. However, the fetal heart rate dropping to 80 bpm during and after a contraction is a sign that the fetus is distressed in utero. PATIENT HISTORY Ask! Is this your ﬁrst baby? Are you expecting more than one baby? How long ago did your membranes ('waters’) rupture? When did you ﬁrst notice the meconium in the amniotic ﬂuid? Is your baby positioned head down or breech? 0447 hrs Reassessment: The mother has another strong contraction and grunts, 'I need to push!’ 0448 hrs Management: With the next three contractions, the midwife delivers the baby. He is ﬂoppy, not moving and not making any eﬀort to breathe. His umbilical cord, ﬁngers and toes are meconium stained. The paramedics quickly suction the baby's oropharynx of meconium and then suction the nares. They dry the baby and stimulate him to breathe by rubbing his back and head with the towel. Then they remove the wet towel and replace it with a warm, dry towel. 0451 hrs Vital signs survey: Perfusion status: HR 78 bpm (auscultation), regular; skin warm, cyanosed. Respiratory status: No respiratory eﬀort following airway clearance. Conscious state: Not moving and ﬂoppy. CONFIRM In this case, the fact that the baby is not breathing is not in dispute. The ﬁrst priority is to ventilate the baby. The baby should be resuscitated in room air initially. Using 100% oxygen may further delay the time taken for him to take his ﬁrst breath. The crew may need to provide supplementary oxygen if his heart rate does not improve with BVM ventilation. The ﬁrst step is to provide BVM ventilation at a rate of 40–60 bpm in air (21%) for at least 30 seconds, then reassess the baby's heart rate and breathing eﬀort. If the heart rate is 60– 100 bpm, BVM ventilation should be continued and supplemental oxygen provided until the heart rate is above 100 bpm and the baby is breathing eﬀectively. If the heart rate is below 60 bpm, chest compressions and 100% oxygen are now indicated. TREAT 0452 hrs: The paramedics provide BVM ventilation at a rate of 30 bpm. This slower rate of ventilation is recommended because meconium aspiration is associated with gas trapping. Slowing the BVM rate enables a longer expiratory time. The paramedics aim for 0.5 seconds for inﬂation and 1.5 seconds for exhalation (2 seconds per inﬂation = 30 bpm). After 30 seconds of eﬀective BVM ventilation, the baby starts to move and opens his eyes. He also takes some breaths on his own. 0453 hrs: Perfusion status: HR 110 bpm (auscultation), skin cyanosed but becoming pink. Respiratory status: 20 bpm, equal air entry bilaterally. Conscious state: The baby has opened his eyes and is moving his legs. His arms remain extended. 0454 hrs: The paramedics stop BVM ventilation as the baby is breathing spontaneously and his heart rate is > 100 bpm. However, the baby develops signs of respiratory distress over the next few minutes. 0456 hrs: Perfusion status: HR 140 (auscultation), skin centrally cyanosed. Respiratory status: 60 bpm, equal air entry bilaterally, barrel-shaped chest, nasal ﬂaring and grunting with each breath. Conscious state: The baby is lying with his eyes closed. He is ﬂexed but does not resist extension of his limbs. 0457 hrs: The paramedics commence oxygen at 2 L/minute via nasal cannula. 0500 hrs: The paramedics prepare to load the mother and baby for transport to hospital and document the events to date. The mother is assisted to the patient stretcher for transport. The baby is placed skin-toskin with her. EVALUATE From the labour and birth history, the paramedics were anticipating this baby was at high risk of compromise at birth. They determine this baby is at risk of respiratory failure secondary to peripartum hypoxia-ischaemia, meconium aspiration. It is therefore anticipated this baby may not respond to initial resuscitation interventions and may continue to deteriorate in response to worsening hypoxia, acidosis, hypercapnia and PPHN. Consideration should be given to securing an airway in this baby for transport to hospital. The paramedics should consult with the neonatal emergency transport team to discuss the need for intubation and for an appropriate destination hospital. Backup from an intensive care ambulance team should be considered. The baby required intubation shortly after arrival at the receiving hospital for worsening respiratory distress. His chest x-ray was consistent with meconium aspiration syndrome. He required ventilation for 48 hours and oxygen therapy for a further 4 days. He received IV antibiotics for 7 days. He was discharged home fully breastfeeding on day 9. CASE STUDY 4: Case 11008, 0500 hrs. Dispatch details A 31-year-old female who is 38 weeks’ pregnant has ruptured her membranes and is having regular contractions. She has gestational diabetes. Initial presentation The paramedics are met at the front door by the patient. They estimate her weight to be 120 kg. She tells them she has been having regular contractions since midnight. She is home alone as her husband is working a night shift and is due home at 7. She phoned for an ambulance when her membranes ruptured. ASSESS 0517 hrs Pertinent hx: The woman informs the paramedics that she was diagnosed with gestational diabetes mellitus (GDM) at 28 weeks’ gestation. Her GDM has been diet controlled. She was booked for a planned induction in 2 days’ time as the baby is large for dates on ultrasound. This is her ﬁrst baby. She has a strong contraction lasting 1 minute and becomes distressed with the pain. The paramedics need to determine whether there are any additional factors placing this baby at risk of requiring resuscitation. They establish that this is a term fetus and that the amniotic ﬂuid was clear of meconium. They ascertain that her membranes ruptured less than 18 hours ago. 0524 hrs Treatment: The paramedics decide to assist the mother into the ambulance and proceed to the nearest maternity hospital, which is 35 km away. On the way, her contractions become closer and last longer. 0545 hrs Treatment: Approximately 30 km into the journey, she becomes extremely distressed with the pain and tells the paramedics she has a strong urge to push. They pull over to the side of the road in a truck stop. With the next four contractions, the baby's head is delivered, but the baby's shoulders are stuck. The baby's head is on the perineum for 6 minutes. They perform the McRobert's manoeuvre (see Ch 54) and the baby's body is born. The baby boy is ﬂoppy. He is not moving or making any eﬀort to breathe. There is no blood or meconium in the amniotic ﬂuid. 0600 hrs Vital signs survey: Perfusion status: HR 40 bpm (auscultation), skin cyanosed. Respiratory status: No respiratory eﬀort. Conscious state: The baby is ﬂoppy. CONFIRM From the birth history, it was anticipated that this baby would be born in poor condition and likely to require resuscitation. At birth, the baby is clearly compromised—not breathing or crying and with poor muscle tone. Given the baby's head was on the perineum for 6 minutes, the most likely problem is a hypoxic ischaemic insult. TREAT Emergency management The paramedics quickly dry the baby and stimulate him to breathe by rubbing his back and head with a towel. They wipe the secretions from the corner of his mouth and nose with a corner of the towel. They remove the wet towel and replace it with a warm, dry towel, and cover the baby's head with a corner of the clean towel. They position him supine on the end of the stretcher with his head in a neutral position and place a small rolled towel under his shoulders to help maintain his head in a neutral position. 0602 hrs: The paramedics provide BVM ventilation at a rate of 60 bpm in air. They are achieving good chest wall rise with each BVM inﬂation. After 30 seconds of eﬀective BVM ventilation, they re-evaluate the baby's heart rate, respiratory eﬀort and muscle tone. A 3-lead ECG is applied to accurately monitor hear rate. There is no change. 0603 hrs: They connect the BVM to 100% oxygen. While one paramedic ventilates at 60 inﬂations per minute, the second auscultates the baby's heart rate again. There is still no change. It is not routine practice to assess for a shockable arrhythmia in a newborn baby. Bradycardia occurs secondary to hypoxaemia, not because of cardiac arrhythmias such as ventricular ﬁbrillation. 0604 hrs: The paramedics commence external chest compressions using the hand-encircling technique with BVM ventilation at a ratio of 3 : 1, using 100% oxygen. After 30 seconds of external chest compressions and BVM ventilation in 100% oxygen, the baby's heart rate is still 50 bpm. They contact the clinician and continue CPR. If the baby's heart rate is > 60 bpm but < 100 bpm, the paramedics should cease chest compressions but continue BVM ventilation, increasing the BVM ventilation rate to 40–60 bpm. They should continue BVM ventilation until the baby's heart rate is > 100 bpm and the baby is breathing spontaneously. If the baby's heart rate is < 60 bpm, the paramedics should continue chest compressions and BVM ventilation at a ratio of 3 : 1 and ensure that they are using 100% oxygen via the BVM. They should reassess the baby after another 30 seconds of chest compressions and BVM ventilation with 100% oxygen. If the baby's heart rate is still < 60 bpm, advanced resuscitation interventions are indicated. The paramedics should call for backup from an intensive care paramedic crew if they have not already done so. 0605 hrs: Perfusion status: HR 70 bpm (auscultation), skin cyanosed, capillary reﬁll > 4 seconds. Respiratory status: RR 15, occasional gasping respirations, good air entry bilaterally with BVM ventilation. Conscious state: The baby has opened his eyes but he remains very ﬂoppy. BGL: 1.1 mmol/L. 0606 hrs: The paramedics proceed to the receiving hospital. They have ceased chest compressions as the baby's heart rate is above 60 bpm but continue BVM ventilation in 100% oxygen at a rate of 40 bpm. They slow down the rate of BVM ventilation to avoid iatrogenic hypocapnia. The baby starts to move and opens his eyes, then takes some breaths on his own. The paramedics administer 1 mg of glucagon IM to treat the baby's low BGL. EVALUATE From the birth history, condition of the baby at birth and initial response to resuscitation interventions, it is clear this baby has experienced signiﬁcant compromise. In this case, the baby may continue to deteriorate. Establishing and maintaining an airway en route to the destination hospital is a priority. The neonatal transport team should be consulted regarding out-of-hospital management of his airway, ventilation and circulation and the most appropriate destination hospital. The baby required intubation and ventilation shortly after arrival at the receiving hospital. Umbilical venous and arterial lines were inserted and maintenance ﬂuids of 10% glucose were commenced and increased at 6 hours of age to 12.5% to treat hypoglycaemia. No abnormalities were detected on chest x-ray, and the full blood count, C-reactive protein and blood cultures were unremarkable. A dopamine infusion was required for 36 hours to treat hypotension. He was treated with therapeutic hypothermia for 72 hours. His MRI on day 4 was essentially normal and he was discharged home on day 10. Hospital management Paramedics need to be aware that a newborn infant of a diabetic mother is at risk of hypoglycaemia secondary to fetal hyperinsulinaemia after birth (Rozance et al., 2016). Babies of diabetic mothers are also at risk of being macrosomic (> 4000 g birth weight) and/or large for gestational age (> 90th percentile). This increases their risk of shoulder dystocia, birth injury, brachial nerve plexus and perinatal asphyxia. Surfactant synthesis can be delayed or inhibited in the fetus because of elevated fetal serum insulin levels, placing the newborn at increased risk of developing respiratory distress (Rozance et al., 2016). Babies with moderate or severe HIE are also at risk of developing adverse neurodevelopmental outcomes as a result of hypoxic ischaemic damage to their brain such as cerebral palsy, cognitive delay and memory diﬃculties. At least 25% of survivors will have signiﬁcant long-term major neurosensory problems (Jacobs & Tarnow-Mordi, 2010). Future research The survival rate for extremely preterm babies plateaued in the middle of the ﬁrst decade after 2000 (Doyle et al., 2011). As it is unlikely that the lower limits of survival will be reduced beyond 22 weeks’ gestation, the focus is on improving the long-term outcomes of extremely premature babies. For example, since 2010 magnesium sulfate has been routinely given to mothers at risk of preterm birth before 30 weeks’ gestation because of its neuroprotective eﬀects for the fetus (Doyle et al., 2009). Therapeutic hypothermia is oﬀering hope to parents whose babies have moderate or severe HIE. If commenced within 6 hours of birth, therapeutic hypothermia can reduce rates of cerebral palsy and cognitive impairment (Jacobs & Tarnow-Mordi, 2010). However, babies must meet strict criteria before this therapy is considered. Paramedics should not commence therapeutic hypothermia in the out-of-hospital environment because of its side eﬀects of deep brain and body hypothermia. Current research is focusing on hypothermia in combination with various therapies, including the use of erythropoietin (Levene, 2010), xenon (a noble anaesthetic gas), cannabinoids and topiramate (an anticonvulsant). Summary Newborn babies rarely require resuscitation at the time of their birth: most newborns make vigorous eﬀorts to inhale air into their lungs at birth and clear their own airway very eﬀectively. Cyanosis is common immediately after birth and heart rate, breathing and muscle tone are the three criteria that should be used to assess the newborn at birth to determine the need for ongoing resuscitation interventions. If the newborn does not start breathing or has a heart rate below 100 bpm after being dried and stimulated, BVM ventilati

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