The Influence of the A118G Polymorphism
of the μ-Opioid Receptor Gene (OPRM1) on the Course of Total Intravenous Anesthesia in Gynecological Patients

• Published in: Obshchai͡a︡ reanimatologii͡a Vol. 11; no. 1; pp. 53 - 63
• Main Authors: Zhenilo, V. M., Makharin, O. A.
• Format: Journal Article
• Language: English
• Published: Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia 26.02.2015
• Subjects: polymorphism; somatosensory evoked potentials; total intravenous anesthesia; μ-opioid receptor
• ISSN: 1813-9779; 2411-7110
• DOI: 10.15360/1813-9779-2015-1-53-63

Objective: to investigate the influence of the A118G polymorphism of the μ-opioid receptor gene (OPRM1) on the course of total intravenous anesthesia. Subjects and methods. A sample consisted of 161 gynecological patients who had under- gone elective surgery under conventional total intravenous anesthesia. Heart rate, noninvasive mean blood pressure, peripheral oxygen saturation, bispectral index, and somatosensory evoked potentials were monitored in all the examinees before and after administration of the induction dose of an anesthetic, in the intraoperative and early postoperative period. The polymorphic variants of the gene in question were determined by allele-specific PCR. Results. According to the identified genotype, the patients were divided into 3 groups: 1) 118A/A genotype carriers (n=101); 2) 118A/G genotype carriers (n=48); 3) 118G/G genotype carriers (n=12). It was intraoperatively found that the 118G/G genotype carriers tended to have hypertension and to consume higher quantities of fentanyl and droperidol than the 118A/A and 118A/G carriers. The intergroup difference in the bispectral index was statistically insignificant during surgery. In the early postoperative period, the 118G-allele homozygotes showed a deeper level of sedation, which correlated with the significantly lower values of the bispectral index (p<0.01) and the higher incidence of adverse reactions (p<0.01). At the same time, the latency and amplitude of somatosensory evoked potentials in the 118G/G genotype carriers showed the least variations as compared to the A-allele homozygotes and heterozygotes (p<0.01). Conclusion. The A118G polymorphism of the μ-opioid receptor gene (OPRM1) affects the course of total intravenous anesthesia. The 118G/G genotype patients needed larger doses of narcotic analgesics, requiring a longer follow-up in the early postoperative period.