- Positive end-expiratory pressure
Positive end-expiratory pressure (PEEP) is the pressure in the lungs (alveolar pressure) above atmospheric pressure (the pressure outside of the body) that exists at the end of expiration. The two types of PEEP are extrinsic PEEP (PEEP applied by a ventilator) and intrinsic PEEP (PEEP caused by a non-complete exhalation).
Extrinsic PEEP (Applied)
A small amount of applied PEEP (3 to 5 cmH2O) is used in most mechanically ventilated patients to mitigate end-expiratory alveolar collapse. A higher level of applied PEEP (>5 cmH2O) is sometimes used to improve hypoxemia or reduce ventilator-associated lung injury in patients with acute lung injury, acute respiratory distress syndrome, or other types of hypoxemic respiratory failure.
Contraindications — There are no absolute contraindications to applied PEEP. However, applied PEEP can have adverse consequences (especially at high levels) and should be used cautiously in patients who have intracranial abnormalities, unilateral or focal lung disease, hypotension, hypovolemia, pulmonary embolism, dynamic hyperinflation without airflow limitation, or a bronchopleural fistula. It may also have undesirable consequences in patients undergoing prone ventilation.
Intrinsic PEEP (Auto)
Auto (Intrinsic) PEEP — Incomplete expiration prior to the initiation of the next breath causes progressive air trapping (hyperinflation). This accumulation of air increases alveolar pressure at the end of expiration, which is referred to as auto-PEEP.
Auto-PEEP develops commonly in high minute ventilation (hyperventilation), expiratory flow limitation (obstructed airway) and expiratory resistance (narrow airway).
Once auto-PEEP is identified, steps should be taken to stop or reduce the pressure build-up. When auto-PEEP persists despite management of its underlying cause, applied PEEP may be helpful if the patient has an expiratory flow limitation (obstruction).
- ^ thefreedictionary.com > positive end-expiratory pressure (PEEP) Citing: Saunders Comprehensive Veterinary Dictionary, copyright 2007
- ^ Manzano F, Fernández-Mondéjar E, Colmenero M, Poyatos ME, Rivera R, Machado J et al. (2008). "Positive-end expiratory pressure reduces incidence of ventilator-associated pneumonia in nonhypoxemic patients.". Crit Care Med 36 (8): 2225-31. doi:10.1097/CCM.0b013e31817b8a92. PMID 18664777. http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=18664777.
- ^ Smith, RA. Physiologic PEEP. Respir Care 1988; 33:620.
- ^ Hasan FM, Beller TA, Sobonya RE, Heller N, Brown GW (1982). "Effect of positive end-expiratory pressure and body position in unilateral lung injury.". J Appl Physiol 52 (1): 147-54. PMID 7037709.
- ^ Huynh T, Messer M, Sing RF, Miles W, Jacobs DG, Thomason MH (2002). "Positive end-expiratory pressure alters intracranial and cerebral perfusion pressure in severe traumatic brain injury.". J Trauma 53 (3): 488-92; discussion 492-3. doi:10.1097/01.TA.0000025657.37314.2F. PMID 12352486.
- ^ Caramez MP, Borges JB, Tucci MR, Okamoto VN, Carvalho CR, Kacmarek RM et al. (2005). "Paradoxical responses to positive end-expiratory pressure in patients with airway obstruction during controlled ventilation.". Crit Care Med 33 (7): 1519-28. PMC PMC2287196. PMID 16003057. http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=16003057.
- ^ Smith TC, Marini JJ (1988). "Impact of PEEP on lung mechanics and work of breathing in severe airflow obstruction.". J Appl Physiol 65 (4): 1488-99. PMID 3053583.
- ^ Kondili E, Alexopoulou C, Prinianakis G, Xirouchaki N, Georgopoulos D (2004). "Pattern of lung emptying and expiratory resistance in mechanically ventilated patients with chronic obstructive pulmonary disease.". Intensive Care Med 30 (7): 1311-8. doi:10.1007/s00134-004-2255-z. PMID 15054570.
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