Randomised controlled trials (RCTs) that compared stimulating catheters with non-stimulating catheters for postoperative analgesia were eligible for inclusion. The blinding of observers was also required for inclusion.
The eligible outcomes included pain scores, the requirement for rescue medication and functional recovery.
The patients in the included trials underwent surgery for total knee replacements, foot surgery, hallux, anterior cruciate repair shoulder surgery, and hand surgery. Patients were scheduled for continuous femoral nerve blocks, popliteal sciatic nerve blocks, anterior interscalene nerve block, and infraclavicular brachial plexus block. The anaesthetic medications used in the trials were lidocaine, prilocaine, mepivacaine and ropivacaine; these were given at a range of doses. Rescue medications included: ketorolac; piritramide and/or metamizol; ropivacaine; intravenous patient-controlled analgesia with morphine, fentanyl and piritramide; nurse-controlled tramadol; and intraoperative supplementation with fentanyl, midazolam, propofol or sufentanil. The outcomes evaluated were the requirement for rescue analgesic medication, pain measured by visual analogue scale at one to five days, onset time of sensory and/or motor block, catheter placement time, patient satisfaction, loss of sensation, motor strength, and functional outcomes (such as disability, knee flexion and walking distance).
Two reviewers independently performed the study selection.