Nicotine Patch for the Prevention of Postoperative Nausea and Vomiting

Patients and Methods

Seventy-five patients classified as ASA (American Society of Anesthesiologists' classification) I/II undergoing laparoscopic cholecystectomy under general anaesthesia between January 1999 and December 2001 were enrolled in the study. Approval was obtained from the Ethics Committee of the University of Medicine, Cluj-Napoca, and written informed consent was obtained from the patients on the evening before surgery.

Patients were divided in three groups: group 1 (n = 25) comprised non-smokers (i.e. patients who never smoked); group 2 (n = 25) comprised patients who had smoked but had given up smoking for at least 5 years, and who received a nicotine patch perioperatively; and group 3 (n = 25) comprised current smokers (i.e. patients smoking >10 cigarettes daily including the preoperative day). In group 2, a patch containing 16.6mg pure nicotine was applied 1 hour before surgery on the upper or medium third of the left arm and was removed 16 hours later; the average delivered dose was 10mg (Pharmacia & Upjohn data file). This dose is recommended for average smokers and the patch used was the only one available on the market during the study.

The evening before surgery, patients were given detailed information about the study and about the side effects of nicotine. Patients with cardiovascular and respiratory diseases and those with a history of PONV or motion sickness were not included in the study. Age >70 years and obesity were also exclusion criteria. All patients were premedicated with diazepam 10mg intramuscularly and pethidine (meperidine) 100mg intramuscularly 90 minutes before the operation (this was the standard premedication in our hospital at the time of the study). In the operating theatre, a peripheral intravenous cannula was inserted and an infusion of 500mL of crystalloid solution was started in all patients.

The anaesthesic technique used for this study was the accepted protocol at that time in our hospitals. General anaesthesia was induced with midazolam 1mg, droperidol 1.25mg, fentanyl 2–3 µg/kg and thiopentone 1.5–2 mg/kg. Tracheal intubation was facilitated with atracurium 0.5–0.6 mg/kg. Anaesthesia was maintained with halothane (end-tidal halothane 1–1.5% minimum alveolar concentration) in 100% oxygen and fentanyl 100µg was given when the heart rate and BP were increased 20% above the preoperative level. During anaesthesia, patients were mechanically ventilated (Taema Alys, France) to maintain end-tidal CO₂ in expired air between 35 and 45mm Hg. After intubation, a nasogastric tube was introduced to empty the stomach of fluids and air. The tube was removed at the end of surgery. During the operation the patients were placed in a reverse Trendelenburg position and 25–35° lateral left decubitus. Intraoperatively, pneumoperitoneum with CO₂ was maintained at a pressure of 12–15mm Hg. BP, heart rate, ECG, inspiratory and expiratory oxygen, halothane concentration and CO₂ were monitored during anaesthesia. At the end of surgery, halothane was discontinued after skin closure and muscle relaxation was antagonised with neostigmine 2.5mg and atropine 1mg.

Postoperatively, all 75 patients were monitored for PONV and pain every 6 hours for the first 24 hours by a blinded observer, who was not able to see the nicotine patch as the patients were instructed to wear pyjamas with long sleeves. No placebo patches were used in controls. The need for rescue antiemetic medication was also recorded. Rescue antiemetic medication consisted of metoclopramide 10–20mg administered intravenously for moderate/severe nausea lasting >10 minutes and/or vomiting. Metoclopramide was the most commonly used antiemetic for PONV in our hospital. Nausea was defined as an unpleasant symptom of possible immediate vomiting. Vomiting was defined as the result of a squeezing action of abdominal muscles with sudden opening of the oesophageal sphincter followed by expulsion of the gastric contents. Retching was defined as an attempt to vomit, not productive of stomach contents.

The data that were collected and analysed included the number of patients who had one or more episodes of nausea only lasting >10 minutes, patients with episodes of vomiting (with or without accompanying nausea) and the total number of patients with PONV. The study did not include assessment of the severity of nausea or vomiting other than in terms of the need for rescue antiemetic medication.

The protocol for managing postoperative analgesia included intravenous administration of dipyrone (metamizole) 2g for patients with a pain visual analogue scale (VAS) score of <3, intravenous ketoprofen for patients with a VAS score of =3 to 5, and intramuscular administration of pethidine 1 mg/kg for patients with a VAS score of =5.

The sample size of 25 patients was calculated with an a error of 0.5, a study power of 95% and an incidence of PONV of 70% in non-smokers and 20% in smokers as reported by us in a pilot study using the same anaesthetic technique.^[16]

Statistical analysis was performed with SPSS for Windows Nominal data (SPSS, Chicago, IL, USA) reported as incidences and analysed using the Chi-square (?²) test or Fisher's Exact test if the minimum expected count was <5. Continuous and discrete data are reported as mean (± SD) and analysed using either the two-sided t-test for independent samples assuming equal variances (the F-test for variances) if the data were normally distributed (the Kolmogorov-Smirnov Liliefors test) or the Mann-Whitney U test. A p-value <0.05 was considered statistically significant. The retrospective power calculation with our results showed a study power of 91%.

Clin Drug Invest. 2007;27(8):559-564. © 2007 Adis Data Information BV

Cite this: Nicotine Patch for the Prevention of Postoperative Nausea and Vomiting - Medscape - Aug 01, 2007.