Analgesia following arthroscopy — a comparison of intra‐articular morphine, pethidine and fentanyl

Publisher Website
Google Scholar
Abstract
It has recently been reported that morphine given in low doses intra‐articularly can produce significant analgesia in patients undergoing arthroscopic knee joint surgery. Data are lacking on the effect of other opioids using a local approach for drug delivery.We studied the analgesic effect of intra‐articular opioids in 70 patients, divided into 7 groups, subjected to arthroscopic knee surgery in general anesthesia. The dimension of the study was based on a power of 0.8 to detect a 25% difference in pain intensity between those receiving opioids locally versus systemically (a=0.05 and β = 0.20). Following surgery, but before terminating anesthesia, the patients received one of the following combinations: 1 mg morphine intra‐articularly (i.art.) + saline intramuscularly (i.m.), 10 mg pethidine i.art + saline i.m., or 10 ug fentanyl i.art + saline i.m. In three additional groups the three opioids were given i.m. and saline given i.art. An additional control group received saline i.art. + i.m.We did not find any significant difference between the groups considering postoperative pain intensity, need for analgesics or considering time to standing/walking or to discharge, analysing each opioid independently. There was, however, a tendency for pethidine i.art. to produce the lowest pain scores both at rest and during movement (P= 0.06). If analysing the results with regards to if opioids were given intra‐articularly or systemically, not considering the type of opioid given, we did however, find a significantly lower total sum of pain scores at movement following local administration (P< 0.05). No specific side‐effects were detected. We conclude that pethidine given intra‐articularly merits further investigation with respect to postoperative analgesia following the activation of peripheral opioid mechanisms.