Description:
<jats:p><jats:bold>ABSTRACT: </jats:bold> Studies of gastric emptying time in laboring women show that delay occurs rarely, except after administration of drugs. In addition to narcotic analgesics, which cause marked delay, other drugs can also delay stomach emptying or provoke aspiration of vomitus, or aggravate its deleterious effects, including muscle relaxants, which abolish the protective cough reflex, and oxytocin in combination with large intravenous loads, which may contribute to pulmonary edema. Fasting may result in lower gastric volume within three to four hours, after which both volume and acidity of gastric juices increase. Emptying the stomach before general anesthesia by means of a nasogastric tube or giving apomorphine to induce vomiting succeeds only if done immediately before induction of anesthesia. Women prefer apomorphine, but it relaxes the gastroesophageal sphincter, making gastric reflux easier. Metoclopramide as an antiemetic has unreliable effects. Antacids can produce chalky particulate matter that is more harmful than clear fluid if aspirated. Other medications used to reduce gastric volume or raise pH have delayed action or deleterious side effects. We conclude that present approaches to preventing aspiration ofvomitus lack efficacy and entail unnecessary risks.</jats:p>