psd-502 and Necrosis

While treating a 63-year-old woman with leg ulcerations, we observed an unusual phenomenon. A wound débridement was planned to remove adherent necrotic material. After topical anesthesia with a lidocaine-prilocaine mixture (EMLA cream) a hemorrhagic,livid margin area developed around the ulcer 90 minutes after application. The area turned necrotic over days and the center was débrided. A more detailed history revealed that similar necrosis had occurred previously when EMLA cream had been employed. We interpreted the current event,as well as the past episodes,as a pathological reaction of the small cutaneous blood vessels to EMLA cream. The history also revealed an overlap connective tissue disease with microvascular impairment. After exposure to the topical anesthetics, the pre-damaged cutaneous blood vessels presumably produced a critical ischemia with subsequent necrosis. Based on this case, we recommend careful use of EMLA cream with frequent monitoring for necrosis when treating patients with a known disorder of microcirculation.

Topics: Anesthetics, Local; Debridement; Diagnosis, Differential; Disease Progression; Drug Eruptions; Female; Humans; Leg Ulcer; Lidocaine; Lidocaine, Prilocaine Drug Combination; Middle Aged; Necrosis; Patch Tests; Prilocaine

Various topical pharmacologic agents have been investigated for their efficacy in preventing or reversing skin flap ischemia. Most of these studies have focused on agents that act on the vascular smooth muscles to cause vasodilatation and improve circulation in the flap. Most of local anesthetics relax vascular smooth muscle and produce peripheral vasodilatation. Topical lidocaine administration was shown that it was an effective and prompt resolution of mechanically induced vasospasm. The topical analgesia cream, EMLA is a mixture of the substances lidocaine and prilocaine. EMLA causes a biphasic vascular response comprising initial blanching and vasoconstriction (maximal after 1.5 h of application) and late erythema and vasodilatation at application times longer than 3 h.. To investigate the effect of EMLA on random flap survival, 40 rats were divided in 2 groups of 20 animals. Caudally based random pattern skin flaps were elevated on dorsa of the rats in 10 x 3 cm dimensions. In group 1 which was the treatment group, topical EMLA was applied and covered with Opsite for 1 week whereas in group 2 which was the control group, carrier for EMLA was applied to the flaps. At the end of treatment period, the areas of flap necrosis were measured and percentages of flap survivals were calculated.. The mean percentages of flap survivals in group 1 and 2 were 81.2 +/- 1.2 percent and 58.7 +/- 2.3 percent, respectively.. Topically administered EMLA might lead to a significant improvement in flap survival. In addition, it is safe, cost-effective, easily applied, and clinically available.

Topics: Administration, Topical; Animals; Graft Survival; Ischemia; Lidocaine; Lidocaine, Prilocaine Drug Combination; Male; Models, Animal; Necrosis; Ointments; Prilocaine; Rats; Rats, Wistar; Skin; Surgical Flaps; Vasodilator Agents

The Eutectic Mixture of Local Anesthetics (EMLA cream) is a topical anesthetic used for providing pain relief in patients undergoing superficial surgical procedures. Cutaneous side-effects have been reported rarely.. We present a case of irritant contact dermatitis induced by EMLA cream in a 6-year-old boy with Wiskott-Aldrich syndrome. Our patient showed clinically a well circumscribed patch corresponding to the site of application of the topical anesthetic. Histopathology showed confluent necrosis of keratinocytes in the upper epidermis, a mixed inflammatory infiltrate with priminent neutrophils in the upper dermis, and focal signs of interface changes including basal cell vacuolization and subepidermal cleft formation.. Graft-vs.-host-disease (GVHD), necrolytic migratory erythema, dermatitis enteropathica and pellagra should be considered in the histopathologic differential diagnosis of acute contact dermatitis caused by EMLA.

Topics: Acrodermatitis; Administration, Topical; Anesthetics, Local; Child; Dermatitis, Contact; Diagnosis, Differential; Drug Eruptions; Erythema; Graft vs Host Disease; Humans; Irritants; Keratinocytes; Lidocaine; Lidocaine, Prilocaine Drug Combination; Male; Necrosis; Pellagra; Prilocaine