No abstract

A "minidose" of 4 mg bupivacaine in combination with 20 microg fentanyl provides spinal anesthesia for surgical repair of hip fracture in the elderly. The minidose combination caused dramatically less hypotension than 10 mg bupivacaine and nearly eliminated the need for vasopressor support of blood pressure.

Continuous femoral "3-in-1" nerve blocks are commonly used for analgesia after total knee arthroplasty (TKA). There are conflicting data as to whether additional sciatic blockade is needed. Our routine use of both continuous femoral (CFI) and sciatic (CSI) peripheral nerve blocks was changed because of concerns that sciatic blockade, and its motor consequences in particular, might obscure diagnosis of perioperative sciatic nerve injury. The revised protocol includes placing single-shot blocks and perineural catheters at both sites, but infusing local anesthetic postoperatively only in the CFI. CSI is reserved for patients having poorly controlled posterior knee or calf pain. A sample group of 12 patients treated with this protocol was followed. Ten of 12 patients required use of the CSI. Within 1 h of a 5-10 mL CSI bolus of 0.2% ropivacaine and beginning an infusion of the same drug at 5 mL/h, patients' median pain by verbal analog scale decreased from 7.5 to 2.0 (mean scores from 7.3 to 2.4). It was possible to maintain this level of analgesia until the third postoperative day when catheters were discontinued. Our experience suggests that, in most patients, adequate analgesia after TKA cannot be achieved with CFI alone and that the addition of CSI renders a significant improvement in analgesia.

The syndrome of transient neurologic symptoms (TNS) after spinal lidocaine has been presumed to be a manifestation of local anesthetic neurotoxicity. Although TNS is not associated with either lidocaine concentration or dose, its incidence has never been examined with very small doses of spinal lidocaine. One hundred ten adult ASA physical status I and II patients presenting for arthroscopic surgery of the knee were randomly assigned to receive spinal anesthesia with either 1% hypobaric lidocaine 50 mg (Group L50) or 1% hypobaric lidocaine 20 mg + 25 microg fentanyl (Group L20/F25). Hemodynamic data, block height and regression, and time to first micturition and discharge were recorded. Follow-up phone calls were made by a blinded researcher at 48-72 h using a standardized questionnaire. Both groups had a median peak cephalad block level of T10. Lidocaine 50 mg was associated with a greater decrease in systolic blood pressure and a greater need for ephedrine. Time until block regression to the S2 dermatome (80 vs. 110 min) and outpatient time to void (130 vs 162 min) and discharge (145 vs. 180 min) were faster in the L20/F25 group. Complaints of TNS were found in 32.7% of the patients in the L50 group and in 3.6% of the patients in the L20/F25 group. We conclude that spinal anesthesia with lidocaine 20 mg + fentanyl 25 microg provided adequate anesthesia with greater hemodynamic stability and faster recovery than spinal anesthesia with lidocaine 50 mg. The incidence of TNS after spinal lidocaine 20 mg + fentanyl 25 microg was significantly less than that after spinal lidocaine 50 mg.