comparison between infusion pumps: fentanyl/ketamine and fentanyl/paracetamol in pain control following tight and leg surgeries

background: adjuvants such as ketamine, promethazine and paracetamol could bring up patients satisfaction and control harmful effects of opioids besides lessening their needed doses, as seen by fentanyl/paracetamol and fentanyl/ketamine combination before. the current study headed to compare paracetamol and ketamine in addition to fentanyl applied by infusion pumps in order to pain relief following major surgery. methods: through a double blinded randomized clinical trial, patients between18 and 65 with elective surgery for tight or leg fractures with asa class 1 and 2 referring to a university hospital in arak, a town in central region of iran, were recruited and used infusion pump for their postoperative pain control. the participants were divided into cases and controls regarding using ketamine/fentanyl (kf) or paracetamol/fentanyl (pf) infusion pumps. results: the mean pain score was totally 3.87 with higher value in kf (5.06) and lower in pf (4.5) immediately after finishing surgery and getting conscious when started using infusion pump. there was no statistical difference between the groups in this regard. concerning the side effects of the applied medications, blood pressure and heart rate had no differences comparing the groups. conclusion: this study showed that paracetamol used in infusion pump can be brilliant in pain control after major surgeries like what done in lower extremities and joint replacement while lessens opioid use. although paracetamol was more effective than ketamine in the current trial, more qualified studies at bigger size and in other fields of surgery beside orthopedic ones would be useful to support the effects if applicable. keywords: infusion pump, ketamine, paracetamol, fentanyl, postoperative pain