title: [Prevention of pulmonary gastric contents aspiration.].
abstract: OBJECTIVE
  Despite its low incidence, aspiration of pulmonary gastric contents may have devastating consequences. Esophageal sphincter function and protective airway reflexes decrease caused by conscience depression, predisposes patients to this severe complication. This article is a review of physiological aspects associated to gastroesophageal reflux, as well as of the methods to prevent it.
  
  
  BACKGROUND
  Comments are made about the mechanisms involved in gastric contents aspiration, its consequences and preventive methods, including recent preoperative fasting guidelines developed after review of the literature, the reasonable use of drugs acting on gastric pH and volume, and finally the effects of different airway control methods on pulmonary aspiration prevention.
  
  
  CONCLUSIONS
  Aspiration of pulmonary gastric contents, despite its low frequency, demands special preventive care. Recently developed preoperative fasting guidelines suggest shorter fasting periods especially for liquids, allowing more comfort to patients and less risk of hypoglycemia and dehydration, without increasing the incidence of perioperative pulmonary aspiration. The routine use of drugs decreasing gastric acidity and volume seems to be indicated only for poor risk patients. The best method to protect airways against aspiration is still tracheal intubation. Other airway control methods have been adopted, but their efficacy in preventing aspiration is lower, although representing major alternatives in cases of intubation failure.
authors.affiliation: Conjunto Hospitalar de Sorocaba/PUC - SP.
authors.forename: Eduardo Toshiyuki
authors.initials: ET
authors.lastname: Moro