Lidocaine For Treatment of Post-operative Pain From Donor Sites Following Burn Injury.

Overview

Burn pain is known to be one the most severe forms of acute pain often requiring large amounts of narcotics in addition to other adjuvants. Topical lidocaine is effective for controlling pain in various settings including dressing changes of burns. The aim of this study is to demonstrate the effectiveness of topical lidocaine in decreasing pain scores and narcotic requirements when applied to donor graft sites while at the same time not interfering with the standard of care TheraBond dressing. During this study the investiagtors will be monitoring for evidence of delayed wound healing, and surgical site infection.

Pain from burns is a severe form of acute pain that requires aggressive use of opioids. Even with the implementation of multiple modalities for analgesia, pain from skin debridements and grafting procedures remains a challenge to control. Local anesthetics have been used for pain relief in burn patients previously as a topical gel or IV infusion and have been found to significantly reduce medication consumption, without apparent adverse effects on wound healing. Lidocaine actually has potent anti-inflammatory effects which could be advantageous on wounds. In addition, topical application of lidocaine to wounds result in different degrees of systemic absorption. High concentrations of lidocaine have potential for central nervous system (seizures (\>5mg/L)) and cardiovascular toxicity (arrhythmias (\>9mg/L)). Plasma concentration of lidocaine depend upon drug dose, rate of absorption, patient weight, physical status and thickness of skin harvested. A prior study where up to 6.7mg/kg of 2% lidocaine with epinephrine was sprayed on donor graft sites found that systemic lidocaine levels were far below toxic levels at their peak (average level of 1.4, with maximum level at 2.2). In this study the levels peaked between 30 and 60 minutes and systemic levels of lidocaine were detectable 6 hours following application of the solution. Studies have demonstrated the beneficial effects of systemic lidocaine administered via IV infusions in reducing perioperative pain scores.Topical lidocaine is effective as a topical anesthetic in multiple clinical trials however only two studies to date has shown that topical lidocaine applied to skin-harvest sites produces an analgesic effect, reduces narcotic requirements while not affecting wound healing or causing toxic blood concentrations. In both these studies systemic intravenous lidocaine levels were monitored and were found to be significantly below toxic limits. The use of topical lidocaine on donor sites is still not widely used, partly for fear the lidocaine will interfere with wound healing and/or dressing adherence. No study to date has demonstrated lidocaine solution to be effective on burn sites when used in conjunction with TheraBond silver foam dressing. TheraBond is an absorbent, atraumatic dressing coated with ionic silver that is routinely used on donor sites at the University of Florida. This study will also offer additional supporting evidence that topical lidocaine is effective in post operative pain management of donor skin sites and should be more widely utilized. In addition, this study will serve as a stepping stone for analyzing different local anesthetic solutions in the future and the potential for reapplication to surgical sites. The purpose of this study is to offer the medical community data on a simple and relatively cheap adjuvant that can be utilized to help reduce the amount of post-operative pain and narcotic requirement in burn patients requiring skin grafts.