[Blocking nociceptive afferents by retrobulbar bupivacaine does not decrease nausea and vomiting after propofol-remifentanil anaesthesia].

UNLABELLED: To test whether prophylactic neural blockade of noziceptive afferents or antiemetics diminutes postoperative nausea and vomiting (PONV) we studied in a randomised, prospective, and ouble-blind fashion 102 patients receiving implantation of an episcleral radioactive applicator for treatment of ocular malignant melanoma during remifentanil-propofol-anaesthesia.

METHODS

15 minutes prior to induction Dolasetron 12.5 mg (n = 18) or 50 mg (n = 20), Ondansetron 8 mg (n = 18), Droperidol 20 microg/kg (n = 23) or NaCl 0.9 % (n = 22) were randomly injected i.v. Furthermore, 4-8 ml Mepivacain 2 %/Bupivacain 0.5 % (n = 52) or saline (n = 50) were injected into the retrobulbar space after anaesthetic induction. Piritramid (0.1 mg/kg) was given for postoperative analgesia 30 minutes before end of surgery. Metamizol (1 g i.v.) and Dolasetron (12.5 mg i.v.) were provided on request as "rescue" medications. Variables were assessed by standardised questioning (NRS; yes/no) before and 1, 6, and 24 hours after surgery.

STATISTICS: Chi(2)-, Mann-Whitney-U-, Kruskal-Wallis-test and logistic regression analysis, p < 0.05.

RESULTS

Although retrobulbar anaesthesia decreased ocular pain (p = 0.013) and total postoperative complaints (p = 0.017) the incidence of PONV was not diminished. Droperidol was the only antiemetic to decrease PONV significantly (p = 0.001).

CONCLUSIONS

Although prophylactic blockade of nozizeptive afferents by retrobulbar anesthesia decreased ocular pain and postoperative complaints, it failed to decrease the incidence of PONV. Thus, PONV after ocular surgery under propofol-remifentanil anaesthesia is not attenuated by preoperative blockade of noziceptive afferents. In patients undergoing total intravenous anaesthesia with propofol-remifentanil, droperidol prevented PONV more effectively than the used serotonin receptor antagonists.