[Effect of intravenous acetaminophen versus fentanyl on postoperative pain after transurethral lithotripsy]. / Efeito do acetaminofeno versus fentanil intravenosos na dor pós litotripsia transuretral.

BACKGROUND: Postoperative pain is the most common postoperative complication. This study was conducted to assess the effect of acetaminophen versus fentanyl on postoperative pain relief in patients who underwent urologic surgeries. METHODS: This clinical trial was conducted on patients aged 18-65 years. Patients were randomly assigned to receive either 2000mg acetaminophen (propacetamol) or 2mcg.kg-1 fentanyl intravenously, 15min before the end of surgery. The postoperative pain was evaluated every 6h for 24h using the Visual Analog Scale. Total morphine dose taken in 24h and hemodynamic status were evaluated. RESULTS: Eighty patients were enrolled into the trial. The mean score of pain in 6, 12, 18, and 24h after surgery was lower in the acetaminophen group than in the fentanyl group but the difference was not statistically significant except in 12 and 18h after surgery (p<0.05). The amount of administered morphine was higher in the fentanyl group than in the acetaminophen group, but the difference was not statistically significant. The hemodynamic status including systolic and diastolic blood pressure and heart rates were nearly the same in the two groups but the SpO2 mean was significantly higher in the acetaminophen group than the fentanyl group. CONCLUSIONS: This trial indicated that intravenous acetaminophen is as effective as intravenous fentanyl in pain relief after urologic surgeries (transurethral lithotripsy).