Premedication with H1 and H2 blocking agents reduces the incidence of postoperative nausea and vomiting

Patients undergoing anaesthesia and surgery frequently complain about postoperative nausea and vomiting (PONV). Whether pretreatment with H1 and H2 blocking agents reduces the incidence of PONV remains controversial. To answer this question, we performed a randomised, prospective, placebo-controlled clinical study to evaluate the efficacy of a premedication with H1 and H2 receptor antagonists.

1149 patients (both sexes) undergoing surgery were randomly assigned to three treatment groups and one control group. Patients in the treatment groups were premedicated with the following H1 + H2 receptor antagonists:Group 1 (n = 335): 5 mg/kg cimetidine i.v. + 0.1 mg/kg dimetindene i.v. 20 min before induction of anaesthesiaGroup 2 (n = 337): 1.25 mg/kg ranitidine i.v. + 0.1 mg/kg dimetindene i.v. 20 min before induction of anaesthesiaGroup 3 (n = 316): 300 mg ranitidine p.o. + 0.1 mg/kg dimetindene i.v. 1 to 2 h before induction of anaesthesiaGroup 4 (n = 161): 20 ml saline solution i.v. 20 min before induction of anaesthesiaPatients from the treatment groups 1, 2 and 3 received regional or general anaesthesia depending on the clinical decision. All control patients received general anaesthesia consisting of fentanyl, a thiobarbiturate, enflurane, nitrous oxide, oxygen, and vecuronium.

The incidence of nausea and vomiting was 8.5%, 6.8% and 5.4% in patients from the treatment groups (1, 2 and 3) who underwent general anaesthesia (n = 545), with no statistically significant differences between groups. The incidence of nausea and vomiting in the control group (n = 161) was 28.3% (nausea) and 27.5% (vomiting), respectively. In patients who underwent regional anaesthesia (n = 443), the incidence of nausea and vomiting was 2.5% and 1.1%, respectively.

Premedication with H1 and H2 blocking agents significantly reduces the incidence of postoperative nausea and vomiting.