Association of μ‐opioid receptor gene polymorphism (A118G) with variations in morphine consumption for analgesia after total knee arthroplasty

Abstract

Background: Morphine consumption after a given surgical procedure can vary considerably. Studies show that single nucleotide polymorphism involving the nucleotide position 118 at exon 1 of the m-opioid receptor gene (OPRM1) may play a role in mediating the effects of opioids. This study was performed to correlate the A118G polymorphism at OPRM1 with morphine consumption in patients undergoing total knee arthroplasty. Methods: Post-operative pain was relieved by patient-controlled analgesia (PCA). The analgesic effect was evaluated using a visual analogue scale. Side-effects, such as sedation, nausea and vomiting, and pruritus, were recorded systematically. The genotypes were determined by sequencing polymerase chain reactionamplified DNA. The differences in demographics and consumed morphine from the PCA device between the different genotypes were tested using one-way analysis of variance. The prevalence of side-effects from morphine and sex distribution were compared using the Kruskal-Wallis test. Results: One hundred and forty-seven patients were included in the study. Twenty-seven patients who required rescue analgesia were excluded; these patients did not differ demographically or

Genetic variability of the μ-opioid receptor influences intrathecal fentanyl analgesia requirements in laboring women ☆

“…morphine via patient-controlled analgesia [10,11,14,23]. In these various settings, patients with at least one 304G allele exhibited a trend towards increased systemic morphine requirements, findings which are in the opposite direction to our results with intrathecal fentanyl.…”

Micro Opioid Receptor A118G Polymorphism and Post-Operative Pain: Opioids' Effects on Heterozigous Patients

“…Few studies have investigated the effect of the Il8A>G polymorphism on post-operative pain or its interaction with other opioids. Two studies were conducted on an Asian population undergoing scheduled gynaecological and orthopaedic surgery: they received POP therapy with morphine by means of PCA (Patient-Controlled-Analgesia) over 48 h: female G 118G homozygotes needed more morphine (33± IOmg) in the first postoperative day than A l18G heterozygotes (29±8mg) or wild-type (27± 1Omg) (19,20). More recently, a study conducted on 138 Japanese patients, undergoing major open abdominal surgery, confirmed that G118G homozygous Assessed for eligibility (n=801 consecutive scheduled surgery'patients)…”

The Influence of Gene Polymorphism OPRM1 118A/G on the Perception of Pain and Pharmacodynamics of Narcotic Analgesics

“…Так, Chou и соавт. показали, что при контролируемой пациентом аналгезии в раннем послеоперационном пе риоде после выполнения артропластики коленного сус тава носители генотипа 118G/G суммарно вводили себе большие дозы морфина (40,4±22 мг) по сравнению с но сительницами генотипа 118A/G (25,6±11,7 мг) и 118A/А (25,3±15,5 мг) [46]. В этом же исследовании по казано, что пациенты чаще вводили себе наркотический аналгетик по сравнению с носителями других геноти пов.…”