The influence of chronic use of opioids on the intensity of the pain after knee and hip replacement surgery

During the last years, has increased significantly the number of patients who take opioids for long time in order to treat pain caused by the severe osteoarthritis. Taking the opioids for long time with the purpose to treat the pain may provoke the risk of addiction as well as possibly change pain perception after surgery. Prospective observational study conducted. Patients aged from 30 to 85, with BMI 20 – 40 prepared for an elective total knee or hip replacement in the case of osteoarthritis, were included. Their habits of medicament use and the impact of various medications on the postsurgical pain intensity were studied. The surgeries were performed under spinal anaesthesia. Postoperatively, patients received multimodal analgesia with NSAIDs, opioids and Morphine as a saviour drug in the case of severe pain, where Visual Analogue Scale (VAS) > 4. Intensity of pain and satisfaction with pain relief were measured in various periods after the surgery applying the VAS score. A telephone survey took a place after the surgeries, not earlier than 30 days after the discharge. 48 patients, 6 in the Opiod User (OPU) group and 42 in the control (CG) group.Total amount of Morphine used for both groups of the study: for the OPU group – 12 mg, for the CG group – 32 mg (P=0,01). There are no significant statistical differences between groups. However, there is a tendency that the OPU group had slightly less pain and had almost three times less consumption of Morphine equivalents in the postsurgical period than the CG group. The results of our study did not confirm the fact that use of opioids before a surgery would make an impact to the more intensive pain and chronification in the postoperative period.