A 38-year-old, morbidly obese woman underwent surgery for debridement of necrotizing fasciitis of the abdominal wall. A pulmonary artery catheter was placed because of increasing fluid requirements. Despite multiple debridements and fluid resuscitation, the patient exhibited severe systemic inflammatory response. It was discovered that fluid placed in the introducer had extravasated into the subcutaneous tissues. In this obese patient, the pulmonary artery introducer was too short.