The relationship of tramadol activity and CYP2D6 gene polymorphism in the treatment of pain in the postoperatie period of patients which was applied total KNEE artroplasty

Tramadol, which is used in the treatment of postoperative pain in patients undergoing total knee arthroplasty, causes less respiratory depression compared to equivalent doses of other opioids, has a lower dependency and tolerance development, and is a frequently used opioid in treatment because it has a low probability of abuse. Tramadol is a synthetic opiate; It is metabolized by the enzyme CYP2D6, a polymorphic enzyme belonging to the cytochrome p450 enzyme system. Investigation of the incidence of pain in patients who underwent knee arthroplasty In this study, in which we examined the effect of post-op opioid administration on patients, we aimed to investigate the metabolic effect of CYP2D6 enzyme on carriers and the effect on VAS score. In this study, 110 patients who underwent total knee anthroplasty in our service in Pamukkale University Faculty of Medicine, Department of Orthopedics and Traumatology, and 100 healthy individuals without complaints as the control group were included. Tramadol 100 mg (contramal) was administered intravenously to each patient. Liman-op 0-15-30-45-60.hastaların min VAS skorları kaydedildi. Sociodemographic characteristics, extremity orientation and laboratory data were recorded. Of the 110 patients in the patient group, 15 (13.6%) were male and 95 (86.4%) were female. The control group consisted of 54 (54%) men and 46 (46%) women. The mean age of the patient group was 67.19 years and the mean age of 57.05 years in the control group. When examined CYP2D6*2-*3-*4-*10 alleles in patient and control groups; In the patient group, CYP2D6*2 allele frequency is 34 alleles (30.9%), CYP2D6*3 allele frequency is 31 (28.2%), CYP2D6*4 allele frequency is 29 alleles (26.4%), in the control group CYP2D6*2 there were 14 alleles (14.0%) allele frequency, CYP2D6*3 allele frequency 25 allele (25%), CYP2D6*4 allele frequency 17 allele (17%) (p<0.050). CYP2D6*3 and CYP2D6* allele frequencies were similar in both groups (p>0.050). We found that these patients were genotype heterozygous for more than one allele. When VAS changes were examined according to their phenotypes, VAS was EM 91.57 at 0 min, VAS IM 75.00 at 15 min, VAS IM 55.21 at 30 min, VAS EM 34.71 at 45 min, VAS IM 26.67 at 60 min calculated. There was a statistically significant difference between VAS changes according to phenotypes only at 60 minutes (p=0.019). In our study, the role of patients in tramadol maintenance was limited, due to the presence of commonly accepted CYP2D6 alleles in the patient group and the absence of carriers of heterozygous (*3/3/, *4/*4, *10/*10) genomes. In our study, we observed that although the VAS, which is accepted as the pain threshold, decreased below 50 at the 60th minute in all patients treated with tramadol after TKA, there was less pain in the EM group. We think that the analysis should be renewed with CYP2D6 enzyme group and different metabolizer groups in a larger study group.