Safety and Pharmacokinetics of EMLA in the Treatment of Postburn Pruritus in Pediatric Patients: A Pilot Study

Abstract

The purpose of this study was to determine the safety and pharmacokinetics of a eutectic mixture of local anesthetics (EMLA) used to ameliorate postburn pruritus after application onto newly formed, intact skin in children. EMLA was applied once to an itchy site where healed skin had formed. Serial blood samples were collected to measure lidocaine, prilocaine, o-toluidine, and methemoglobin. Maximal plasma concentration, minimal plasma concentration, time to achieve the maximal plasma concentration, elimination half-life, and area under the concentration-time curve were calculated. Vital signs, oxygen saturation, clinical signs of hypoxia, and itch intensity were measured. Five children had 15.7 +/- 2.54 g (+/- SD) of EMLA applied to a skin surface area of 93.0 +/- 37.0 cm2. Lidocaine and prilocaine concentrations were below toxic levels; o-toluidine was not detected. Methemoglobin remained between 1 and 3%; patients did not exhibit any clinical signs of hypoxia. Mean oxygen saturation was 98.9 +/- 0.01%. The mean number of pruritic episodes and antihistamine breakthrough doses were greater in the 2 prestudy control days compared with study day 3 (P = 0.01 and P = 0.03, respectively). Skin at the site of EMLA application remained anesthetized for 12 to 13 hours. In this small pilot study, EMLA seems to be a safe, novel treatment for postburn pruritus in burned children when applied to newly healed, intact skin.

Role of Pregabalin in Management of Pruritus: A Literature Review

“…The most commonly used drugs to reduce the post burn itch, are antihistamines. Unfortunately, these drugs have not impressive therapeutic effects on all patients (33,34); therefore, researchers have studied the antipruritic effects of the other drugs such as local anesthetics (35), naltrexon (36), gabapentin (37)(38)(39), and pregabalin in the management of post burn pruritus.…”

Postoperative Pain and Other Acute Pain Syndromes

“…Topical application has been shown to be effective for the treatment of postburn pain 481 and pruritus. 482 However, local anesthetics pose an increased risk for rapid systemic uptake and toxicity when applied to non-intact skin and can potentially cause seizures 483 or dysrhythmias. Lidocaine, when given by IV infusion, has significant opioidreducing effects 484 and acts to decrease inflammation at the burn site.…”

Regional Anesthetic Techniques for the Pediatric Patient

“…An occlusive dressing is usually applied over the application site. Because of its potential for systemic toxicity, EMLA cream should not be in prolonged contact with mucous membranes or with traumatized skin [62][63][64] . Common uses include anesthesia for venipuncture, neonatal circumcision, and laser ablation of port-wine stains [65][66][67][68][69][70] .…”