Respiratory Distress Syndrome (RDS) in Neonates

Acute Conditions of Neonates

Respiratory Distress Syndrome (RDS)

• This Syndrome is also known as hyaline membrane disease (HDM)
• RDS primarily affects premature newborns
• RDS is characterized by breathing difficulty, insufficient oxygen exchange in the lungs, and reduced lung volume
• Premature white infants are more susceptible than black infants
• Males are almost twice as likely to develop RDS
• Preterm infants, infants of diabetic mothers, infants born via cesarean, and those with decreased lung blood perfusion are more likely to develop RDS
• RDS is caused by a deficiency of surfactant
• Surfactant is a substance that keeps the air sacs in the lungs open

Precipitating Factors for RDS

• Prematurity, specifically births before 32 weeks gestation, increases the risk of RDS, due to inadequate surfactant production
• Maternal factors like diabetes, pre-eclampsia, and substance abuse can elevate RDS risk in newborns
• Specific genetic factors, like mutations affecting surfactant production genes, increase RDS risk
• Other factors include fetal distress and mechanical ventilation during labor

Pathophysiology of RDS

• RDS is caused by a lack of surfactant, leading to collapse of the air sacs
• Collapsed air sacs make oxygen intake difficult, increasing breathing effort and causing fatigue
• Prolonged distress results in hypoxemia, hypercarbia, and acidosis
• Hypoxemia and hypercapnia can cause acidosis, negatively impacting the newborn's health
• These conditions lead to pulmonary vasoconstriction and persistent fetal circulation with right-to-left shunting
• Hypoxemia is worsened by the shunting, leading to multi-system organ dysfunction
• The described cycle continues until oxygen-carbon dioxide exchange is inadequate to sustain life without ventilator support

Clinical Characteristics of RDS

• Difficulty initiating respirations at birth occurs for most infants who develop RDS
• After resuscitation, there might be a brief symptom-free period due to initial surfactant release
• Subtle signs of RDS include:
  • Low body temperature
  • Nasal flaring
  • Sternal and subcostal retractions
  • Tachypnea (more than 60 respirations per minute)
  • Cyanotic mucous membranes
  • Expiratory grunting
    • This grunting is caused by the closure of the glottis
    • It creates a prolonged expiratory time
    • A partially closed glottis is helpful because it increases pressure in the alveoli on expiration
    • Pressure in the alveoli keep the alveoli from collapsing, allowing for more complete oxygen exchange

Manifestations of distress from RDS

• Seesaw respirations occur
• Heart failure is indicated by decreased urine output and edema of the extremities
• Pale gray skin
• Periods of apnea
• Bradycardia
• Pneumothorax
• Chest X-ray reveals ground glass (haziness)
• Respiratory acidosis comes from umbilical vessel catheter blood gas studies
• Cyanosis, decreased PO2, and decreased oxygen saturation levels occur as the disease progresses
• Fine rales and diminished breath sounds occur during auscultation

Complications of RDS

• Hypoxia
• The physiologic complications that lead to increased hypoxia also decrease pulmonary perfusion
• Impairment or absence of metabolic response to cold occurs
• A reversion to anaerobic metabolism occurs resulting in lactate accumulation (acidosis), and impaired output, which decreases perfusion to vital organs
• Respiratory acidosis, where increased pCO2 and decreased pH result from alveolar hypoventilation
• Carbon dioxide retention and subsequent respiratory acidosis are indicators of ventilator inadequacy
• Persistently rising pCO2 and decreasing pH show poor pulmonary function
• Metabolic acidosis can occur where decreased pH and bicarbonate levels can be the result of impaired oxygen to the cells
• Due to a lack of oxygen, neonates begin anaerobic metabolism, which increases lactate levels and a base deficit
• Lactate levels increase and pH decreases (acidotic), buffer base decreases to try and compensate and maintain acid-base homeostasis

Nursing Diagnosis for RDS in Newborns

• Ineffective breathing pattern related to decreased lung compliance and surfactant deficiency
• Altered gas exchange related to decreased lung volume and collapse of air sacs
• Risk for imbalanced fluid volume related to increased fluid accumulation in the lungs and decreased lung compliance
• Risk for impaired tissue perfusion related to decreased oxygenation and increased carbon dioxide retention
• Risk for infection related to prolonged mechanical ventilation and intubation
• Altered family processes related to stress and anxiety associated with caring for an infant with RDS

Management of RDS

• Clear the airway and ensure breathing adequacy and circulation
• Surfactant replacement, synthetic surfactant is sprayed into the lungs by a syringe
• A catheter is used through an endotracheal tube at birth
• Position the infant with the head upright and then tilted downward.
• This can be used if a newborn struggles to breathe despite nCPAP
• Oxygen administration
• Oxygen administration is necessary to maintain proper pO2 and pH levels
• Provide warm, humidified oxygen
• Administer with a head box
• An FiO2 meter and pulse oximeter are used to determine amount of oxygen required
  • Retinopathy of prematurity and bronchopulmonary dysplasia can occur as a possible complication for immature or very sick infants
• Ventilation is used to prevent hypoventilation and hypoxia
  • Increased humidified oxygen concentration maybe be adequate for mild cases
  • CPAP may be use for moderately afflicted infants
  • Severe cases require mechanical ventilation with positive end-expiratory pressure (PEEP)
  • Nasal continuous positive airway pressure (nCPAP) is a device to support breathing by gently pushing air into the lungs through prongs in the nose
  • Mechanical ventilation is used in very serious cases and is life support.
  • The machine is connected to a breathing tube through a the mouth or nose into windpipe
  • Newborn who require ventilation could develop bronchopulmonary dysplasia
  • Newborns may develop health problems from the breathing tube or ventilator, such as an airway or lung injury
• Correction of acid-base abnormalities
• Homeostasis is given with supportive care
• Fluids and nutrients can prevent malnutrition and promote growth
• Nutrition is critical to growth and lung development
• Environmental temperature regulation
• Maintenance of correct temperature is essential.
• Hypothermia could aggravate RDS
• Infants with RDS must be kept warm to prevent cooling and increased acidosis of all newborns
• Protection from infection
• Adequate haemoglobin must be maintained.
• Neonates with RDS require a packed cell volume (PCV) above 40% (less than 75%)
• Broad-spectrum antibiotics may be started for all preterm babies with respiratory distress

Meconium Aspiration Syndrome (MAS)

• Early as 10 weeks' gestation, meconium is present in the fetal bowel
• When an infant experiences hypoxia in utero, the rectal sphincter relaxes due to a vagal reflex, releasing meconium into the amniotic fluid
• Babies born breech can release meconium into the amniotic fluid due to pressure on the buttocks
• The release of meconium into the amniotic fluid causes it to turn a green or greenish-black color
• Meconium staining occurs in approximately 10-12% of all pregnancies
• Infants can aspirate meconium in utero or with their first breath after birth
• Meconium can cause severe respiratory distress via:
  • Inflammation of bronchioles
  • Mechanical plugging of small bronchioles
  • Lung cell trauma

MAS causes:

• Hypoxemia
• Carbon dioxide retention
• Intrapulmonary shunting
• Injured tissue may cause secondary infection leading to pneumonia

Clinical Manifestations of MAS

• Difficulties establishing respirations at birth can occur
• Especially for breech births
• Hypoxic episodes in utero can cause meconium release in amniotic fluid
• APGAR score is apt to be low
• Tachypnea and coarse bronchial sounds are present
• Retractions occur
• Inflammation of bronchi tends to trap air in the alveoli, limiting oxygen entrance
• Air trapping causes the anteroposterior diameter of the chest (barrel chest) to enlarge
• Cyanosis can occur
• Respiratory acidosis occurs with decreased PO2 and increased PCO2
• Chest radiograph shows bilateral coarse infiltrates with spaces of hyperaeration (peculiar honeycomb effect)

Complications of MAS

• Respiratory distress, because meconium blocks the air sacs of the lungs
• Hypoxia occurs due to insufficient oxygen in the blood
  • Is life-threatening if left untreated
• Pneumonia due to the aspiration of meconium causing lung infections
• Pulmonary hypertension occurs when the meconium constricts the blood vessels in the lungs
• It increases blood pressure and decreases blood flow
• Bronchopulmonary dysplasia (BPD) can result, which is a chronic lung disease
• Primary for premature newborns with mechanical ventilation
• Death occurs when MAS is life-threatening and result in death

Therapeutic Management of MAS

• Amniotransfusion/Amuninfusion can reduce the amount of meconium in amniotic fluid to reduce aspiration risk
• Suction with bulb syringe or catheter on the perineum prior to the birth of the shoulders to prevent aspiration of meconium
• Cesarean birth and tracheal are needed for deeply meconium-stained amniotic fluid
• Oxygen administration and ventilation may be needed after birth
• Oxygen under pressure (bag and mask) should not be administered before intubation and suction, to avoid driving small plugs of meconium into lungs
• Antibiotic therapy to stop pneumonia development
• Administering surfactant increases lung compliance

Management to prevent increasing metabolic oxygen demands

• Maintain a temperature-neutral environment
• Chest physiotherapy with clapping and vibration to encourage removal of meconium

Nursing Management of MAS

• Prevent Meconium Aspiration
• Initial interventions are to prevent aspiration via removing meconium from the infant's naso- and oropharynx before the first breath
• Promote patient's physical well being
• Promoting gas exchange and minimizing complications is supportive with significant aspiration

Nursing Interventions after resuscitation

• Maintain adequate oxygenation and ventilation
• Temperature regulation
• Glucose strip test at two hours of age to check for hypoglycemia
• Observe intravenous fluids
• Calculate necessary fluids (could be restricted within 48-72 hours due to cerebral edema)
• Provide caloric requirements

Sepsis

• Is a serious bacterial infection in newborns within the first month
• Can be caused by group B streptococcus, Escherichia coli, and Staphylococcus aureus
  • Typically these bacteria do not cause significant disease in older children
• Sepsis neonatorum

Incidence of Sepsis

• Severe infection occurs 0.5 to 2 per 1000 live newborns
• Neonatal sepsis is responsible for 1 million deaths yearly

Predisposing Factors for Sepsis

• Premature infants
• They have not fully developed their immune systems
• They are more susceptible to infection
• Low birth weight
• This increases risk due to a greater surface area-to-volume ratio
• Prolonged rupture of membranes
• This increases the risk when the baby is exposed for an extended period
• Maternal chorioamnionitis
• Maternal infections
• urinary trac or genital tract infections
• Blood type incompatibility
• In the event of rH incompatibility, the mothers immune system produces antibodies that cross the placenta
• Use of instruments during delivery
• Forceps or vacuum extraction increase risk of sepsis
• Maternal substance abuse
• Congenital abnormalities
• Including neural tube defects or congenital heart disease
• Bodies may have a difficult time to fight off infections

Pathophysiology of neonatal sepsis

• Bacteria spreads from the mother or the environment into the bloodstream
• Lead to a systemic inflammatory response
• Lead to harmful effects on the body

Clinical Manifestations of Sepsis

• Subtle behavioral changes
• The infant "isn't doing well"
• The infant is irritable or lethargic and hypotonic
• Color changes occur that include pallor, duskiness, cyanosis, or a “shocky” appearance, and skin is cool and clammy
• Temperature instability
• Results in the need to adjust the temperature of the isolette
• Poor feeding
• Evidenced by decrease in total intake, abdominal distention, vomiting, lack of interest in feeding, and diarrhea
• Hyperbilirubinemia
• Onset of apnea

Signs and Symptoms of Sepsis

• CNS disease
• jitteriness, tremors, seizure activity Respiratory system disease
• Tachypnea, labored respirations, apnea, cyanosis Hematologic disease
• jaundice, petechial hemorrhages, hepatosplenomegaly Gastrointestinal disease
• Diarrhea, vomiting, bile stained aspirate, hepatomegaly

Diagnostic Procedures for Sepsis

• Clinical examination
• Laboratory tests
• Imaging studies

Lab tests for Sepsis

• Blood cultures determine pathogen type to guide antibiotic selection
• Complete blood count (CBC) assesses overall health and identifies changes in white blood cell count
• C-reactive protein (CRP) test measures CRP level for inflammation
• Liver function tests assess overall health and identify changes in liver function
• Urinalysis can help determine if there is a urinary tract infection
• Lumbar puncture (spinal tap) can collect cerebrospinal fluid (CSF) to diagnose meningitis
• Chest X-ray identifies lung changes, such as infection or pneumonia

Nursing Problems related to Sepsis

• Risk for Infection
  • Newborns with sepsis are at risk for developing additional infections
  • Precautions decrease risk of exposure to pathogens
• Impaired Gas Exchange
• Newborns need oxygen therapy
• Imbalanced Nutrition
  • Additional nutritional support to maintain energy levels to fight the infection

Potential Deficits: Sepsis

• Fluid volume deficit requires fluid and electrolyte replacement
• Risk for Shock
• This occurs when the circulatory system cannot deliver oxygen to the body's tissues
• There is acute pain
• The patient experience pain
• Altered Body Temperature
• Patients may experience this

Management of Neonatal Sepsis

• Antibiotics that are used depend on the pathogen
• May need adjustment based on results of blood cultures and sensitivity tests
• Fluid and electrolyte replacement needed to support organ function
• Nutritional support maintain energy levels
• The newborn's vital signs may need to be monitored and recorded.
• Oxygen therapy supports breathing
• Blood transfusion may replace lost blood and maintain blood pressure
• Ventilatory support may be required to support breathing

Nursing Responsibilities

• Monitoring vital signs is important
  • Temperature, pulse, respiratory rate, and blood pressure
  • Any changes may indicate the presence of an infection or complications.
• Administering medications
• Nurses administer antibiotics or other medications to treat infection and manage symptoms
• Assessing for signs of infection
  • Regular assessment for signs of that is important to prompt early treatment
  • Skin color, increased redness or swelling at a site, and a new or worsening fever
• Administering fluid and electrolyte therapy
  • Fluid and electrolytes help with imbalances from the infection
• Monitoring for signs of shock
  • Nurses monitor for the signs of shock,
  • Decreased blood pressure, weak pulse, and decreased Urine output, take appropriate action
• Monitor the newborn for pneumonia, meningitis, and organ dysfunction, and healthcare provider
• Providing emotional support
  • Emotional support and referrals to social services are helpful for the newborns and families