Autologous Fat Grafting: A Study of Residual Intracellular Adipocyte Lidocaine Concentrations after Serial Rinsing with Normal Saline

Abstract

Introduction: With evolution of sophisticated lipocontouring techniques increased interest has developed in utilization of vacuum harvested autologous fat cells for grafting purposes. Transplantation of viable adipocytes for contour augmentation, enlargement, or filling of defects has clinically become more important. Based on evidence that lidocaine solution may alter the metabolic activity, evaluation of the effects of multiple rinsing was undertaken. Materials and Methods: Gas chromatography was utilized to measure changes in intracellular concentration of lidocaine from closed syringe harvested adipocytes following serial rinsing with equal volumes of normal saline in preparation for fat grafting procedures. Results: Use of standard tumescent local anesthesia as a medium for harvesting mature fat cells via closed syringe techniques resulted in substantial absorption of lidocaine. Statistically significant reduction of intracellular lidocaine was accomplished via serial rinsing with normal saline solution. It was concluded that a minumum of three rinses utilizing equal volume of saline to autologous fat achieved significant and substantial reduction of intracellular lidocaine levels, but did not result in complete removal. Discussion: The importance of thorough rinsing and removal of cellular debris from harvested fat cell grafts prior to transfer is widely recognized to improve efficacy and predictability. This study proves that serial rinsing of fat cells harvested with closed syringe system using a tumescent fluid technique does statistically reduce the retention of intracellular lidocaine. It is believed that high concentrations of retained intracellular lidocaine may inhibit the metabolic activity and impact the survivability of autologous fat grafts.