Postoperative nausea and vomiting (PONV) are frequent after surgery and anaesthesia. Dexamethasone is widely used as antiemetic for the prevention of PONV. Little is known about the efficacy of antiemetic drugs for the treatment of established PONV symptoms. No single randomised trial has been published so far that tests the efficacy of dexamethasone for the treatment of established PONV symptoms. In this trial the investigators want to test the antiemetic efficacy of three different doses of intravenous dexamethasone for the treatment of established PONV symptoms. In adjunct protocols of this study the investigators aim to establish a novel method to quantify the anti-nausea efficacy of an antiemetic drug, to study pharmacogenetics of PONV, and to further our understanding on the smoking status as a predictive factor of PONV.
Name: PlaceboDescription: Injection of placebo (saline 0.9%)Type: Drug
Injection of Placebo
Name: Dexamethasone 3 mgDescription: 10 ml Seringue with DexamethasoneType: Drug
Dexamethasone 3 mg
Name: Dexamethasone 6 mgDescription: 10 ml Seringue with DexamethasoneType: Drug
Dexamethasone 6 mg
Name: Dexamethasone 12 mgDescription: 10 ml Seringue with DexamethasoneType: Drug
Dexamethasone 12 mg
Description: Complete absence of any nausea and/or vomiting (including retching) in a previously nauseated or vomiting patient within 24 hours after administration of the study treatment.Measure: Treatment efficacy of Dexamethasone for established PONV Time: 24 hour follow up
Description: Free from PONV during the first 6 hoursMeasure: Short term efficacity Time: 6 hours
Description: Number of patients staying PONV free after rescue antiemetic during the first 24 postoperative hoursMeasure: PONV free after rescue antiemtic Time: 24 hour follow up
Description: quality of sleep during the first postoperative night (numerical rating scale ranging from 0 = no sleep at all to 10 = excellent sleep)Measure: Quality of sleep Time: 24 hour follow up
Description: any minor or major adverse effects during 24h.Measure: Minor or major adverse effects Time: 24 hour follow up
There is one SNP
The SNP rs4680 (c.472G > A) is a missense mutation leading to a four-fold reduction of the COMT enzyme.
The COMT Val158Met polymorphism (rs4680) will be genotyped using a commercially available TaqMan® SNP genotyping assay (C_25746809_50, Applied Biosystems, Warrington, UK).