Superwet anesthesia redefines large-volume liposuction

Superwet anesthesia is a method of regional anesthesia for liposuction surgery that uses an evenly distributed, rapidly infused solution under pressure, until tissue blanching and moderate tension are achieved, in a ratio of 0.5 to 1.5 ml per milliliter of injectate to lipoaspirate. It is accompanied by systemic anesthesia and supplemented with intravenous hydration. The efficacy of superwet formulation for regional anesthesia was evaluated in a consecutive series of 20 patients who underwent large-volume (>1500 ml) liposuction. The average volume of injectate was 2285 ml and fat aspirate was 2437.5 ml. The average fluid volume fractionated from the aspirate infranatant was 507.5 ml, and the amount of injectate absorbed was 1775.5 ml. The mean "pure fat" fractionation was 1930 ml. Approximately 21% to 22% of injected fluid is not absorbed, so the ratio of fat removed to fluid absorbed by hypodermoclysis is in the range of 11. Consequently, this requires an alteration in traditional fluid replacement levels. This also alters the threshold of what has been traditionally considered "large"-volume liposuction so that the traditional 1500 ml defining large-volume aspirate may no longer be applicable. To achieve consistency in reporting, all liposuction data should be standardized to routinely include the volumes of injectate, aspirate, and infranatant fluid fractionation.