Effects of anesthesia versus regional nerve block on major leg amputation mortality rate

There are greater than 120,000 above-knee amputations (AKA) and below-knee amputations (BKA) performed in the USA each year. Traditionally, general anesthesia (GA) was the preferred modality of anesthesia. The use of regional nerve blocks has recently gained popularity, however, without the supporting evidence of any mortality benefits. Our objective was to evaluate whether regional nerve blocks yield significant mortality reduction in major lower-extremity amputations. Retrospective data of both AKA and BKA procedures at the Maimonides Medical Center from 2005 to 2009 were analyzed. Patients received either general sedation, spinal or ultrasound-guided regional nerve blocks as per decision of the attending anesthesiologist. Regional nerve blocks for major lower-extremity amputations consisted of femoral, sciatic, saphenous and popliteal nerve blocks. A retrospective inquiry of 30-day mortality was performed with reference to the Social Security Death Index and hospital records. One hundred and fifty-eight patients were included in the study (82 men and 86 women with mean age of 74.5 years ± 12.9 SD, range of 33-98 years) of which 46 patients had regional nerve blocks and 112 had GA or spinal blocks. Patients who received both regional blocks and GA/spinal blocks within 30 days were excluded. The overall 30-day mortality was 17.1% (27 patients) consisting of 15.2% for regional nerve analgesia versus 17.9% for GA/spinal blocks (P = 0.867). Age did not affect mortality outcome in either groups of anesthesia modality. Our analysis did not reveal any mortality benefit of utilizing regional nerve block over GA or spinal blocks.