Prospective study of lidocaine, bupivacaine, and epinephrine levels and blood loss in patients undergoing liposuction and abdominoplasty.

BACKGROUND

Bupivacaine levels have not been measured in cosmetic surgery patients to establish safety. Blood loss has been underestimated using the small volumes present in the aspirate. The proportion of wetting solution removed by liposuction has not been reliably ascertained.

METHODS

To remedy these deficiencies, a prospective study was undertaken among 322 consecutive patients presenting for superwet ultrasonic liposuction and/or abdominoplasty, and other combined procedures, using infusions containing 0.05% lidocaine (liposuction) and/or 0.025% bupivacaine (abdominoplasty) with 1:500,000 epinephrine. Plasma levels of lidocaine, bupivacaine, and epinephrine were studied in a subset of 76 consecutive patients, including hourly intraoperative samples in 39 consecutive patients. Anesthetic levels were also measured in 12 consecutive patients during the 24-hour period after infusion.

RESULTS

The maximum lidocaine dose was 3243 mg and the maximum level was 2.10 μg/ml. The maximum bupivacaine dose was 550 mg and the maximum level was 0.81 μg/ml. No clinical toxicity was encountered. Estimated blood loss from liposuction was 217.5 cc + 187 cc/liter of aspirate (r = 0.65). Abdominoplasty added 290 cc of blood loss, on average. The mean proportion of wetting solution removed by liposuction was 9.8 percent.

CONCLUSIONS

Bupivacaine may be safely used in cosmetic surgery. A concentration of 1:500,000 epinephrine is safe and effective when administered as part of a wetting solution that is limited to less than 5 liters. Estimated blood loss is higher than previous estimates based on lipocrits. Combination procedures are safe.