Randomized double blind comparison between sciatic-femoral nerve block and propofol-remifentanil, propofol-alfentanil general anesthetics in out-patient knee arthroscopy

The aim of this study is the evaluation preparation and discharge times as well as the side-effects, patient satisfaction and costs after out-patient knee arthroscopy performed with a combined sciatic-femoral nerve block or a propofol-remifentanil, propofol-alfentanil general anesthetics. Sixty patients, (remifentanil group 1, n = 20), (alfentanil group 2, n = 20) and a combined sciatic-femoral nerve block (PNB group 3, n = 20). In group 1, anesthesia was induced with remifentanil (1 mic kg(-1) followed by 0.5 mic kg(-1) min(-1) i.v), in group 2 alfentanil (20 mic kg(-1) followed by 2 mic kg(-1) min(-1) i.v, in both groups (group 1, 2) propofol was given 2 mg kg(-1) i.v followed by 9 mg kg(-1) h(-1) i.v. Patients then received atracurium 0.6 mg kg(-1) i.v. to facilitate endotracheal intubation. In the PNB group (group 3), patients received a sciatic-femoral nerve block with ropivacaine 25 mL 0.75 mg using a multiple injection technique aided by a nerve stimulator and a short, bevelled, Teflon-coated stimulating needle. There was no significant difference in the duration of stay in the post anesthesia care unit and day surgery unit between groups, there was significant increase in the time to first urination in PNB group than the other two groups. Also there was no significant difference in the stay in delay surgery. The cost of disposal materials, preoperative and post operative times were higher in PNB group. The cost of drugs was higher in remifentanil and alfentanil groups than PNB group; the total cost was insignificant in the three groups. In conclusion, this prospective randomized study suggests that in patients undergoing out-patient arthroscopy, a combined sciatic-femoral nerve block (using a small volume of ropivacaine 0.75%) compared with a propofol-remifentanil or propofol-alfentanil general anesthetics techniques may provide similar intraoperative analgesic efficacy, a shorter length of stay in the PACU and an increased likelihood of bypassing the first phase of postoperative recovery.