CURRENT Essentials of Critical Care.pdf

Chapter 8 Respiratory Failure 103■■Noninvasive Positive Pressure Ventilation (NIPPV)Essential Concepts• Delivery of positive-pressure ventilation without endotrachealtube via nasal or oronasal facemask; success depends on alert,cooperative patient with proper fitting interface• Continuous positive airway pressure (CPAP): delivers constantpressure during both inspiration and expiration• Bilevel devices: cycle between two different positive pressures;inspiratory pressure (IPAP) set higher than expiratory pressure(EPAP)• Useful in select patients with acute or chronic respiratory failure• Obstructive sleep apnea (OSA): maintains upper airway patency• COPD: improves gas exchange, vital signs, dyspnea scores; reducesneed for invasive mechanical ventilation• Weaning from invasive mechanical ventilation: shorter durationof support, fewer ICU days, improved 60-day mortality• Pulmonary edema: afterload reduction and improved cardiacoutput achieved by lowering left ventricular transmural pressure• Contraindications: acute respiratory arrest, ischemia, hypotensiveshock, uncontrolled arrhythmias, excessive secretions, inabilityto protect airway, facial abnormalities• Complications: nasal bridge skin breakdown, sinus congestion,sinusitis, dry eyes, dry mouth, headache, gastric distentionEssentials of Management• OSA: CPAP treatment of choice; if unable to tolerate high pressurelevels required to maintain airway patency switch to bileveldevice adjusting EPAP level until obstructive apneas abolished;adjust IPAP level to reduce hypopneas, desaturations, snoring• COPD: Bilevel devices with high IPAP to reduce work of inspiratorymuscles and EPAP lower than intrinsic PEEP• Pulmonary edema: CPAP starting at 10–12.5 cm H 2 O; cautionwith bilevel modes until further studies available■ PearlPatients are not subject to the potential complications of intubation,loss of airway defense mechanisms, and self-extubation with the useof NIPPV compared to invasive mechanical ventilation.ReferenceLiesching T et al: Acute applications of noninvasive positive pressure ventilation.Chest 2003 Aug;124:699. [PMID: 1290756]