The burn eschar is the major source of infection in the severely burned patient, and it hampers healing and prevents skin grafting. Tangential excision has been shown to be safe for rapid removal of the eschar. For the last 14 months we have used this method beginning about 7 days postinjury. Our burn unit is composed of a four-bed, horizontal, laminar airflow isolation system, and transfer out of the sterile environment to the operating room would expose the patient to airborne contamination. Intramuscular ketamine anesthesia was used to allow major debridement to be carried out in the unit itself. Forty-five patients aged 18 months to 71 years have undergone 150 excisions in the burn unit under anesthesia with no complications. The burns ranged from 20 to 75% of body surface (mean, 40%). Because ketamine is a cardiorespiratory stimulant, ventilation and vital signs were well maintained. Psychological side effects of ketamine were minimal, particularly in the younger age group.