Anaesthesia and emesis. I: Etiology.

Abstract

The most recent studies suggest that in the absence of antiemetics the incidence of emetic problems associated with anaesthesia is still around 30 per cent. Although not strictly comparable, these observations are little different from those in the last two or three decades. In this review we have discussed the part played by age, sex, obesity, operative site and duration of anaesthesia and unfortunately these are all predetermined. Postoperative vomiting, however, is rarely the result of a single factor and it is for this reason that management may not be successful. The anaesthetist has therefore been forced to adopt a practice reliant on antiemetics for symptomatic control. Of the factors under our control the evidence available would indicate that large doses of opiates, and over-enthusiastic manual ventilation by mask may adversely affect the incidence of postoperative vomiting. However, prompt pain relief, normotension and gentle care during the postoperative period are preventative measures that may also help reduce the distressing symptoms of emesis. In part II of this review we will discuss the general and specific measures available for the prevention and treatment of emesis during the postoperative period.