A prospective, randomized placebo-controlled study was undertaken to compare the effects on heart rate and blood pressure during surgery and on the incidence of
nausea,
vomiting and
headache after surgery of i.m.
prochlorperazine 0.2 mg.kg-1, i.v.
prochlorperazine 0.1 mg.kg-1 and i.v.
ondansetron 0.06 mg.kg-1 given at induction of general anaesthesia to patients undergoing septorhinoplasty. The effects of the test drugs after administration on heart rate and blood pressure were similar, as were the incidences of retching and
vomiting in the recovery ward after each test
drug. Postoperatively, compared with placebo (7%),
nausea per se was most frequent in those given i.v.
prochlorperazine (25%, P < 0.01), and less frequent in those given i.m.
prochlorperazine (2%) and i.v.
ondansetron (15%).
Vomiting per se was reduced from 24% to 7% (P < 0.025) by i.v.
prochlorperazine and to 4% (P < 0.0005) by i.v.
ondansetron. The incidence of
nausea with
vomiting was reduced from 35% to 15% (P < 0.025). 16% (P < 0.05) and 11% (P < 0.005) by i.m.
prochlorperazine, i.v.
prochlorperazine and i.v.
ondansetron respectively. I.m.
prochlorperazine and i.v.
ondansetron increased the frequency (from 35% to 64%, P < 0.0005 and to 71%, P < 0.0005, respectively) of those experiencing no
PONV and delayed the onset of
PONV, but only i.m.
prochlorperazine reduced the severity of
postoperative vomiting.
Headache was frequent in the control (69%), i.v.
prochlorperazine (62%) and i.v.
ondansetron (69%) groups, and least frequent after i.m.
prochlorperazine (53%; P < 0.05 versus i.v.
ondansetron). It is concluded that these drugs have no adverse cardiovascular effects within 10 minutes of administration, i.m.
prochlorperazine and i.v.
ondansetron reduce
PONV more effectively than i.v.
prochlorperazine and postoperative
headache after septorhinoplasty occurs less frequently in those given i.m.
prochlorperazine than in those given i.v.
ondansetron.