title: Auto-PEEP in respiratory failure.
abstract: Intrinsic positive end-expiratory pressure (auto-PEEP) is a common occurrence in patients with acute respiratory failure requiring mechanical ventilation. Auto-PEEP can cause severe respiratory and hemodynamic compromise. The presence of auto-PEEP should be suspected when airflow at end-exhalation is not zero. In patients receiving controlled mechanical ventilation, auto-PEEP can be estimated measuring the rise in airway pressure during an end-expiratory occlusion maneuver. In patients who trigger the ventilator or who are not connected to a ventilator, auto-PEEP can be estimated by simultaneous recordings of airflow and airway and esophageal pressure, respectively. The best technique to accurately measure auto-PEEP in patients who actively recruit their expiratory muscle remains controversial. Strategies that may reduce auto-PEEP include reduction of minute ventilation, use of small tidal volumes and prolongation of the time available for exhalation. In patients in whom auto-PEEP is caused by expiratory flow limitation, the application of low-levels of external PEEP can reduce dyspnea, reduce work of breathing, improve patient-ventilator interaction and cardiac function, all without worsening hyperinflation. Neurally adjusted ventilatory assist, a novel strategy of ventilatory assist, may improve patient-ventilator interaction in patients with auto-PEEP.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Edward Hines Jr. Veterans Administration Hospital, Loyola University of Chicago Stritch School of Medicine, Hines, IL 60141, USA. flaghi@lumc.edu
authors.forename: F
authors.initials: F
authors.lastname: Laghi
authors.forename: A
authors.initials: A
authors.lastname: Goyal
mesh_terms: D006801:Humans; D018467:Positive-Pressure Respiration, Intrinsic / Q000150:complications / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D012131:Respiratory Insufficiency / Q000150:complications*