Effects of OPRM1A118G and CYP3A4*18B genetic polymorphism and the interaction on postoperative analgesia with fentanyl in patients undergoing radical resection of lung cancer

Abstract

Objective To evaluate the effects of OPRM1A118G and CYP3A4*18B genetic polymorphism and the interaction on postoperative analgesia with fentanyl in the patients undergoing radical resection of lung cancer. Methods One hundred and thirty-nine patients (native of Henan province), aged 40-64 yr, weighing 40-70 kg, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, scheduled for elective radical resection of lung cancer under general anesthesia, were enrolled in this study.The polymorphic sites of the OPRM1A118G and CYP3A4*18B allele were analyzed by using polymerase chain reaction technique and ABI 3130 Genetic Analyzer.The patients were divided into wild homozygote group (group AA, group *1/*1), heterozygote group (group AG, group *1/*18B) and mutation homozygote group (group GG, group *18B/*18B) according to their genotypes.The patients were divided into 7 groups according to the interaction between the two genes: AA plus *1/*1 group (group Ⅰ), AA plus *1/*18B group (group Ⅱ), AG plus *1/*1 group (group Ⅲ), AG plus *1/*18B group (group Ⅳ), GG plus *1/*1 group (group Ⅴ), GG plus *1/*18B group (group Ⅵ) and *18B/*18B group (group Ⅶ). Patient-controlled intravenous analgesia with fentanyl was started at the end of surgery to maintain the visual analogue scale ≤3 points.The amount of fentanyl used within 24 and 48 h after surgery was recorded, and the occurrence of adverse reactions within 48 h after surgery was observed. Results The amount of fentanyl used within 24 and 48 h after surgery was significantly higher in group GG than in group AA (P 0.05). Conclusion OPRM1A118G and CYP3A4*18B genetic polymorphism and the interaction are the genetic factors contributing to individual variation in fentanyl pharmacodynamics in the patients undergoing radical resection of lung cancer. Key words: Polymorphism, single nucleotide; Fentanyl; Lung neoplasms; Analgesia, patient-controlled