Most studies of postoperative nausea and vomiting have concentrated on
single etiologic factors and have not detailed the method of assessin
g these symptoms. This study used postoperative interview data from pa
tients at four teaching hospitals during 1988-89, to determine 1) risk
factors for nausea/vomiting, 2) whether the type of surgery affected
the rate of nausea/vomiting among female patients, 3) whether differen
ces in rates across hospitals were due to differences in patient case-
mix, and 4) whether there were differences in the rate of nausea/vomit
ing among the patients of individual anesthesiologists. Research nurse
s performed 16,000 interviews (59% of all inpatients) from a closed-qu
estion standardized format. With a multiple logistic regression that c
ontrolled simultaneously for all risk factors, factors associated with
increased risk for nausea/vomiting for all patients included younger
age, female, lower physical status score, no preoperative medical cond
itions, nonsmokers, elective procedures, longer duration of anesthesia
, inhaled anesthetics, use of intraoperative opioids, and gynecologic
or ophthalmologic operations. Among women, risk factors were similar,
with minor gynecologic surgery associated with increased risk (relativ
e odds = 2.30). We found marked variations in the rate of nausea/vomit
ing across hospitals (range, 39% to 73%), and these variations were no
t explained by the case-mix of patients. The rate of nausea/vomiting v
aried substantially across anesthesiologists in each hospital and the
differences were not explained by differences in the patients they man
aged. Thus in the time period immediately preceding the introduction o
f newer antiemetic drugs, we found that the rates of this common probl
em were persistently high as perceived from the patients' point of vie
w.