A comparison of three regional anaesthesia techniques for outpatient knee arthroscopy

Purpose

The purpose of this study was to compare intraoperative conditions and postoperative pain control of three penpheral regional anaesthesia techniques for outpatient knee arthroscopic procedures.

Methods

Sixty patients were randomized to one of three groups. Group IA received portal injections (10 ml lidocaine 1%), intraarticular lidocaine (20 ml CO₂ lidocaine 2% with 1/200.000 adrenaline) and a placebo femoral nerve block (20 ml saline). Group FNB received a femoral 3-in-1 nerve block (20 ml chloroprocaine 2% with 1/200.000 adrenaline), placebo portal injections (10 ml saline) and placebo intraarticular saline (20 ml saline with 1/200.000 adrenaline). Group FNB + IA received a femoral 3-m-1 nerve block, intraarticular hdocaine and placebo portal injections. The following were assessed: intraoperative pain (10 cm VAS: 0 = no pain. 10 = extreme pain), surgical operating conditions (1 = excellent. 4 = unacceptable), intraoperative use of sedation and analgesia, time to discharge, patient satisfaction score (1= very satisfied, 5 very unsatisfied) and postoperative analgesia. Data were analyzed using ANOVA, Kruskal-Wallis, and Chi-square tests as appropriate. P< 0.05 was considered significant.

Results

There were no differences among the groups regarding any of the vanables tested. Considerable postoperative pain (VAS> 5) was expenenced by 20/54 (37%) patients.

Conclusion

Any of the three anaesthetic techniques tested provide reliable intraoperative patient and surgical conditions for outpatient knee arthroscopy. Patient discomfort postoperatively was considerable in all groups and requires further investigation.