Home Mechanical Ventilation (Respiratory Care Science 4) PDF

‫جـــــامعــة ابن النفيس للعلوم الطبية‬ University of Ibn Al-Nafis For Medical Sciences Respiratory Care science 4 Home Mechanical Ventilation 3ed year respiratory therapist student Dr:MOHAMMED-SENAN BS, RCP,FNIV, MsRC Goals Extend the durat...

‫جـــــامعــة ابن النفيس للعلوم الطبية‬ University of Ibn Al-Nafis For Medical Sciences Respiratory Care science 4 Home Mechanical Ventilation 3ed year respiratory therapist student Dr:MOHAMMED-SENAN BS, RCP,FNIV, MsRC Goals Extend the duration of life Enhance the quality of life Reduce morbidity Improve physiologic function Achieve normal life routin Reduce overall health care costs JUn224 DrMohammmed Senana 2 Indications Disorders of the respiratory pump Neuromuscular diseases, chest wall diseases, spinal cord injury Obstructive diseases of the airway Craniofacial abnormalities, hypotonia, obesity,COPD,Asethma Parenchymal lung disease ILD, cystic fibrosis Disorders of control of respiration central hypoventilation syndrome Inability to wean from mechanical ventilation After and acute illness After prolonged ventilation for a chronic disease Progressive chronic respiratory failure Sleep disturbance JUn224 Central or obstructive, apnea or DrMohammmed hypopnea Senana 3 Indications/Symptoms Indications/Criteria Shortness of breath Forced vital capacity < Especially on exertion or lying 50% predicted down Maximal Inspiratory Morning headache and Pressure < 60 insomnia ABG pCO2 > 45 Fatigue and lethargy Moderate to severe sleep Increased respiratory rate apnea Restlessness and anxiety JUn224 DrMohammmed Senana 4 Patients Cardiopulmonary stability Positive trend in nutrition/maintenance Stamina for play or daily activities while ventilated Freedom from active/recurrent infection, fever, deterioration Interfaces Noninvasive vs. Invasive Age Cognitive ability Body habitus Ventilatory needs Anticipated length of ventilation Family/patient preference JUn224 DrMohammmed Senana 5 Definition ❖ Noninvasive ventilation (NIV): is defined as a ventilatory mode that delivers a mechanical ventilatory support breath without use of an endotracheal tube or surgical airway, but using a tight-fitting face or nasal mask. ❖ The decision to intubate and mechanically ventilate or to institute noninvasive ventilation support >>> is generally made purely on clinical grounds without delay for laboratory evaluation. It is two types: CPAP & BiPAP. o CPAP does not directly increase tidal volume or minute ventilation. o In contrast, bilevel positive airway pressure (BiPAP) provides supplemental inspiratory tidal volume. JUn224 DrMohammmed Senana 6 Indications Disorders of the respiratory pump Neuromuscular diseases, chest wall diseases, spinal cord injury Obstructive diseases of the airway Craniofacial abnormalities, hypotonia, obesity,COPD,Asethma Parenchymal lung disease ILD, cystic fibrosis Disorders of control of respiration central hypoventilation syndrome Inability to wean from mechanical ventilation After and acute illness After prolonged ventilation for a chronic disease Progressive chronic respiratory failure Sleep disturbance JUn224 Central or obstructive, apnea or DrMohammmed hypopnea Senana 7 Indications for the use of NIV ❑ NIV is commonly used for the treatment of respiratory failure from: o Exacerbation of chronic obstructive airways disease (COPD). o Pulmonary oedema. o Respiratory failure in immunocompromised patients. E.g. AIDS, malignancy. o Weaning from conventional ventilation and prevention of need for reintubation in high risk patients. o Asthma. Idiopathic Pulmonary Fibrosis. Obesity hypoventilation. Neuromuscular Respiratory Diseases. Do-not - intubate status in terminal illness or malignancies. JUn224 DrMohammmed Senana 8 Contra Indications Relative Contraindications ❖Absolute: o Cardiac instability  Coma – Shock and need for pressor support – Ventricular dysrhythmias  Cardiac arrest – Complicated acute myocardial infarction  Respiratory arrest o GI bleeding (- Intractable emesis and/or uncontrollable bleeding)  Any condition requiring o Inability to protect airway Intubation. – Impaired cough or swallowing – Poor clearance of secretions  Non-compliant patient – Depressed sensorium and lethargy o Status epilepticus o Potential for upper airway obstruction – Extensive head and neck tumors – Any other tumor with extrinsic airway compression – JUn224Angioedema or anaphylaxis causing airway compromise DrMohammmed Senana 9 Guidelines for providing NIV >>Duration of treatment Patients who benefit from NIV during the first 4 hours of treatment should receive NIV for as long as possible (a minimum of 6 hours) during the first 24 hours (Evidence A) Treatment should last until the acute cause has resolved, commonly after about 3 days When NIV is successful (pH>7.35,resolution of cause, normalization of RR) after 24 hrs/more – plan weaning JUn224 DrMohammmed Senana 10 Protocol for initiation of NIV ✓1. Appropriately monitored location ✓2. Patient in bed or chair sitting at > 30‐degree angle ✓3 A full‐face mask should be used for the first 24 hours, followed by switching to a nasal mask if preferred by the patient (Evidence) ✓4.Encourage patient to hold mask ✓5. Apply harness; avoid excessive strap tension ✓6.Connect interface to ventilator tubing and turn on ventilator ✓7. Check for air leaks, readjust straps as needed JUn224 DrMohammmed Senana 11 Guidelines for providing NIV 1.An initial IPAP of 10 cm H2O & EPAP of 4–5 cm H2O should be used (Evidence A). 2.IPAP should be increased by 2–5 cm increments at a rate of approximately 5 cm H2O every 10mins, with a usual IPAP target of 20 cm H2O or until a therapeutic response is achieved or patient tolerability has been reached (Evidence A). 3. O2 should be entrained into the circuit and the flow adjusted to SpO2 >88–92% (Evidence B) JUn224 DrMohammmed Senana 12 OXYGENATION AND HUMIDIFICATION Oxygen is titrated to achieve a desired oxygen saturation of 90% to 92%. Use of oxygen blenders Adjusting liter flow delivered via oxygen tubing connected directly to the mask or ventilator circuit Heated blow over vaporizer should be used if longer application intended. JUn224 DrMohammmed Senana 13 Bronchodilators ▪ Preferably administered off NIV ▪ If necessary be entrained between the expiration port and face mask ▪ Delivery of both oxygen and nebulized solutions is affected by NIV pressure settings (Evidence A) ❖If a nasogastric tube is in place, a fine bore tube is preferred to minimize mask leakage(Evidence C). JUn224 DrMohammmed Senana 14 Criteria for Terminating NIV and Switching to Mechanical ventilation Worsening pH and PaCO2 Tachypnea (over 30 bpm) Hemodynamic instability SpO2 < 90% Decreased level of consciousness Inability to clear secretions Inability to tolerate interface JUn224 DrMohammmed Senana 15 Weaning strategy(A) 1. Continue NIV for 16 hours on day 2 2.Continue NIV for 12 hours on day 3 including 6–8 hours overnight use 3.Discontinue NIV on day 4, unless continuation is clinically indicated. JUn224 DrMohammmed Senana 16  Assess ment of NIV JUn224 DrMohammmed Senana 17 Noninvasive interfaces Nasal masks Full facemasks Nasal pillows Sipper mouthpiece Lipseal/mouthpiece device JUn224 DrMohammmed Senana 18 NIV: Nasal mask / Prongs Many older patients prefer compared to mouthpiece Problems: Leak, especially mouth Nasal bridge pressure with mask Gum erosion or compression with mask Nasal erosion with prongs Chin strap may be needed JUn224 DrMohammmed Senana 19 NIV: Full face mask Decreased leak Decreased –Cough –Talking –Eating Increased risk of aspiration Nocturnal use with daytime nasal mask JUn224 DrMohammmed Senana 20 NIV: Sipper /Lipseal Mouthpiece Daytime use Allows facial freedom Flexed mouthpiece +/- custom orthodontics Intermittently used to augment breathing Continuously used JUn224 DrMohammmed Senana 21 Tracheostomies Shiley, Bivona, Portex and others Pediatric sizes mimic ETT ID’s Neonatal, pediatric, adult and customized lengths Cuffed and uncuffed Disposable inner cannula models JUn224 DrMohammmed Senana 22 Complications of NIV Facial and orthodontic changes Aerophagia (PIP > 25 cmH2O) Nasal drying/congestion = humidify Volutrauma - air leak Inadequate ventilation JUn224 DrMohammmed Senana 23 Ventilators JUn224 DrMohammmed Senana 24 CPAP ❑ Continuous positive airways pressure (CPAP) implies application of a preset positive pressure throughout the respiratory cycle (i.e. inspiratory and expiratory phases) in a spontaneously breathing patient. Continuous Positive Airway Pressure For simple sleep apnea Stents open the airway Decreases work of breathing JUn224 DrMohammmed Senana 25 CPAP Normal Respiration. CPAP: Provides static positive airway pressure throughout the respiratory cycle‐ both inspiration & expiration. Facilitates inhalation by reducing pressure thresholds to initiate airflow. JUn224 DrMohammmed Senana 26 How CPAP works? 1.CPAP splints the airway throughout the respiratory cycle, 2. Increases ↑ (FRC) the functional residual capacity of the lungs by holding airways open and preventing collapse. 3.Also causes the patient to breathe at higher lung volumes, making the lungs more compliant 4. Provides effective chest wall stabilization, 5. Improves ventilation-perfusion mismatch and thereby improves oxygenation. JUn224 DrMohammmed Senana 27 Benefits of CPAP ↑O2 saturation ↓ Work of breathing ↓ cardiac workload by (↑ Intrathoracic Pressure which will ↓ preload ). JUn224 DrMohammmed Senana 28 Use of CPAP 1.In the U.K., guidelines call for using CPAP with patients being weaned from ventilation; patients who are hypoxemic following extubation; or patients with a variety of acute conditions “who are hypoxic but not exhausted” (i.e., those who are ventilating themselves adequately). 2.OSA ( obstructive sleep apnoea syndrome) JUn224 DrMohammmed Senana 29 OSA ( Obstructive Sleep Apnoea) Sleep-disordered breathing (upper airway obstruction during sleep) occurs in around 20% of the adult population. It ranges from snoring to obstructive sleep apnoea (OSA), the latter being characterized by cessation of breathing for at least 10 s in the presence of inspiratory effort. The incidence of clinically relevant OSA has been estimated to be around 22% in the general surgical population, with 70% of patients being undiagnosed at preoperative evaluation. Patients with OSA are at increased risk of perioperative complications: including hypoxaemia, hypercapnoea, arrhythmias, myocardial ischaemia, delirium, and unplanned intensive care unit admissions. JUn224 DrMohammmed Senana 30 BiPAP Pressure Support Ventilation IPAP—the inspiratory positive airway pressure—extra help when breathing in EPAP—the expiratory positive airway pressure--CPAP Cycles based on patient initiated breaths Available with timed back-up rates Used for severe sleep apnea, neuromuscular weakness or insufficiency JUn224 DrMohammmed Senana 31 BiPAP( Bilevel Positive Airway Pressure) ❑ BIPAP:has two levels of continuous airway pressure. IPAP:When the machine senses the patient's inspiratory flow starting to increase, it increases the inspiratory pressure applied, so that air flow is enhanced and the patient's own inspiratory tidal volume is augmented. EPAP. When the machine senses flow is slowing or stopped, it reduces the applied airway pressure so the patient has less work upon exhaling, but maintains a continuous positive expiratory pressure. JUn224 DrMohammmed Senana 32 BiPAP JUn224 DrMohammmed Senana 33 BiPAP Increases in inspiratory pressure are helpful to alleviate dyspnea Increases in expiratory pressure are better to improve oxygenation JUn224 DrMohammmed Senana 34 BiPAP JUn224 DrMohammmed Senana 35 Ventilator settings IPAP/ EPAP→ start with 10/5 cm H2O (With a goal to achieve VT of 6-7ml/kg) Increase IPAP → by 2 cm H2O increments up to maximum 20-25 cm H2O,if hypercapnia persists. Do not exceed 25cm H2O at any point of time. Increase EPAP → by 2 CmH2O if hypoxia, maximum 10-15 cm H2O. Back up respiratory rate → 12-16/minute. FIO2 → 1.0 to be adjusted to have SaO2 90% JUn224 DrMohammmed Senana 36  Which initial pressure settings to use for BiPAP© spontaneous mode? ❑ Commonly the IPAP is set to 10 cmH2O and the EPAP to 5 cmH2O. o The response to these pressures should determine future changes. o Most machines can generate maximal pressures of 20-23 cmH2O. o If higher pressures are required leakage around the mask is usually a problem, ‐ conventional invasive ventilation is indicated. JUn224 DrMohammmed Senana 37  What FiO2 to choose? ❖Choose an initial FiO2 slightly higher to that what the patient received prior to NIV. Adjust the FiO2 to achieve an SaO2 that you deem appropriate for their underlying disease. (Generally SaO2 above 92% is acceptable). If a patient is hypoxic while breathing 100% oxygen on a CPAP circuit, their hypoxia will not improve if they are placed onto a BiPAP circuit (in spite of the increased ventilatory assistance) because the FiO2 will drop significantly. Similarly if a patient starts to work harder on a BiPAP circuit they may become more hypoxic due to a drop in FiO2 caused by increased gas flow through the breathing circuit. JUn224 DrMohammmed Senana 38 How to monitor the patient’s response to NIV? The most useful indicator is → How the patient feels. Patient compliance is the best indicator. (Patient should be able to tell you if feels better or worse). Where available arterial blood gases (ABG) are useful to assess → changes in oxygenation and CO2 clearance. Predictor of Success of NIV With a trial of ventilation for 1-2 hours → Normally Leads to ▪↓ Decrease in PaCO2 greater than 8 mmHg ▪↑ Increase in pH greater than 0.06 JUn224 DrMohammmed Senana 39 How to Predict failure? ❑ Again, this is largely based on how the patient feels and ABG results. ❖If the patient is getting increasingly tired, or their ABG deteriorating despite optimal settings, then they will probably need tracheal intubation and mechanical ventilation. ❖It is important to recognize the failure to respond as soon as possible so that management may be planned before the patient collapses. JUn224 DrMohammmed Senana 40 Predictor of Failure ❖ Severity of illness: – Acidosis (pH 80 and pH 4. (stuporous, arousal only after vigorous stimulation; inconsistently follows commands) – Encephalopathy score >3.( major confusion, daytime sleepiness or agitation) – Glasgow Coma Scale score lower than < 8. ❖Failure to improve with 12-24 hours of NIV JUn224 DrMohammmed Senana 41 ❖BiPAP can only augment the patient's respiration; it should not be used as a primary form of ventilation. ❑The tidal volume received by the patient depends upon: ✓airway resistance, ✓lung and chest wall compliance ✓patient synchrony with machine, ✓absence of air leakage around the mask. JUn224 DrMohammmed Senana 42 Monitoring BP, RR, HR & rhythm, O2 saturation, Level of conscious state. Treatment tolerance. o Initially,@ 15 minutely for 1 hour, @30 minutely for 2 hours, @ 1 hourly for 2 hours, then 4 hourly SPO2: Aiming for 94-98% (or 88-92% in CO2 retainers). ABGs → Prior to commencement, at 1 hour, within 1 hour of setting changed, then as clinically needed. JUn224 DrMohammmed Senana 43 Advantages of NIV Decreases incidence of Intubation. Decreases Mortality. Decreases ICU & Hospital Stay. VAP can be avoided. Intubation related complications can be avoided. Cost effective. JUn224 DrMohammmed Senana 44 Complications 1.Facial & Nasal pressure injury. 2.Gastric distention 3.Drying of mucous membranes of nose, nasal congestion & thick secretions. 4.Aspiration of Gastric contents. 5.General discomfort 6.Claustrophobia JUn224 DrMohammmed Senana 45 Literature review ❖A 1995 study in the New England Journal of Medicine found→ BiPAP ↓reduced the need for endotracheal intubation, as well as hospital length of stay and mortality, in acutely ill COPD patients with a → PaO2 less than 45 mm Hg, (pH) level less than 7.35, and (RR) greater than 30 breaths/minute. ❖A 2003 Cochrane review of studies with mostly COPD patients also found that BiPAP→ ↓ decreased mortality, incidence of ventilator-associated pneumonia, ICU and hospital length of stay, total duration of JUn224 DrMohammmed Senana 46 Strong Evidence – Level A (multiple controlled trials) Acute hypercapnic COPD Acute cardiogenic Pulmonary Oedema – most evidence for CPAP Immunocompromised patients Less strong – Level B (single controlled trials, multiple case series) Asthma Community Acquired Pneumonia in COPD patients Facilitation of weaning in COPD Avoidance of extubation failure Post Operative Respiratory Failure Do not intubate patients JUn224 DrMohammmed Senana 47 Weak Evidence(few case series)No benefit in controlled trials) ARDS Community acquired pneumonia – non COPD Cystic fibrosis Weaning – non COPD OSA/ obesity hypoventilation Trauma Not indicated o Acute deterioration in ILD. o Severe ARDS with multi organ failure. o Post op Upper airway, esophageal surgery. JUn224 DrMohammmed Senana 48 Present Status of NIV The application of mechanical ventilatory support through a mask in place of endotracheal intubation is becoming increasingly accepted and used in the emergency department & ICU settings. JUn224 DrMohammmed Senana 49 Summery ✓COPD is the most suitable condition for noninvasive ventilation. ✓ Noninvasive ventilation is most effective in patients with moderate- to-severe disease. ✓ Hypercapnic respiratory acidosis may define the best responders ( pH 7.20-7.30). – Noninvasive ventilation is also effective in patients with a pH of 7.35- 7.30, but no added benefit is appreciated if the pH is greater than 7.35. – The lowest threshold of effectiveness is unknown, but success has been achieved with pH values as low as 7.10. ✓ Obtunded COPD patients can be treated, but the success rate is lower. ✓ Improvement after a 1- to 2-hour trial may predict success. JUn224 DrMohammmed Senana 50 Ventilator Choice Noninvasive vs. invasive Portability Battery life Setting capabilities Reliability Community support JUn224 DrMohammmed Senana 51 Full Ventilation Noninvasive or invasive Pressure cycled or volume cycled SIMV vs. AC Allows pressure support, PEEP, inspiratory time, flow to be added and manipulated JUn224 DrMohammmed Senana 52 Control vs. SIMV CONTROL MODE SIMV MODE Every breath fully supported Vent synchronizes to support Can’t wean by decreasing patient effort rate Patient takes own breaths Risk of hyperventilation if between vent breaths agitated Increased work of breathing vs. control JUn224 DrMohammmed Senana 56 Assist Control Mode Can trigger breaths, but needs support with each breath JUn224 DrMohammmed Senana 57 SIMV Mode Most patients, improved comfort, stable CO2s JUn224 DrMohammmed Senana 58 Pressure vs. Volume Pressure Tidal volume changes as Volume patient compliance No limit on pressure unless changes set Potential hypoventilation Square wave pattern results or overexpansion in higher pressure delivered Obstructed trach decreases for same volume delivered delivered volume JUn224 DrMohammmed Senana 61 Pressure vs. Volume Pressure control Volume control Set pressure, volume Set volume, pressure variable variable Better control of Better control of oxygenation than ventilation than ventilation oxygenation Better for younger, Better for older more noncompliant lungs compliant lungs JUn224 DrMohammmed Senana 62 JUn224 DrMohammmed Senana 63 JUn224 DrMohammmed Senana 64 Pressure Support Trigger by patient Provides inspiratory flow during inspiration Given in addition to vent breaths in IMV modes or alone without a set rate, mimicking BiPAP JUn224 DrMohammmed Senana 66 Bilevel Mode Mimic BiPAP / No Backup Rate JUn224 DrMohammmed Senana 67 Supporting Equipment External support—PEEP Alarms/Monitoring Pulse oximetry, Apnea monitor, Capnography Humidification External w/ heater, HME Airway clearance Suctioning, Vest, cough assist Talking devices JUn224 DrMohammmed Senana 68 Discharge Criteria Presence of a stable airway FiO2 less than 40% PCO2 safely maintained Nutritional intake optimal Other medical conditions well controlled Above may vary if palliative care JUn224 DrMohammmed Senana 69 Discharge Criteria Goals and plans clarified with family and caregivers Family and respite caregivers trained in the ventilation, clearance, prevention, evaluation and all equipment Nursing support arranged for nighttime Equipment lists developed and implemented with re- supply and funding addressed Funding and insurance issues addressed JUn224 DrMohammmed Senana 70 Continuing Assessment Titration sleep studies Blood gases Bronchoscopy Home monitoring Used more frequently when weaning/decannulating JUn224 DrMohammmed Senana 71 Complications Ventilator failure Tracheostomy issues Decannulation, blockage, infection Mask-related issues Pressure sores, facial growth issues Under- or over-ventilation JUn224 DrMohammmed Senana 72 Outcomes Dependent on underlying disease Over 70% 10-year survival, most deaths due to underlying disease In retrospective studies, 0-8% of deaths were ventilator or technology-related Occasional hospitalization JUn224 DrMohammmed Senana 73 Quality of Life Generally good Fewer hospitalizations Better sleep quality Better daytime functioning Some stress for patients, caregivers Related to amount of care and support needed JUn224 DrMohammmed Senana 74  Home ventilation reality Every patient is unique These are guidelines not rules Vary settings, interfaces, strategies to achieve goals of good health and optimized quality of life Team approach necessary JUn224 DrMohammmed Senana 75  Thank you for attention ,,, JUn224 DrMohammmed Senana 76  Have a great day DrMohammmed Senana JUn224 77