Heatstroke in the Super-sized Athlete Ericka Fink, MD,* Barbara W. Brandom, MD, y and Klaus D. Torp, MDz Abstract: We present a 16-year-old male athlete with hyperthermia, altered mental status, and respiratory distress during summer football practice. Multisystem organ failure ensued, which he survived. Malignant hyperthermia was suspected in this patient who had a history of rhabdomyolysis. Specific muscle contracture testing later eliminated this diagnosis. This case discusses the importance of rapid hydration with isonatremic fluid, aggressive cooling, and full support measures, including plasmapheresis, further diagnostic efforts to evaluate potential causes of rhabdomyolysis, and planning for physi- cal and emotional rehabilitation. Key Words: heatstroke, exertional heat injury, multiorgan system injury, rhabdomyolysis, dantrolene CASE A 16-year old, 135-kg male athlete presented to a local hospital unresponsive, hyperthermic, tachypneic, diaphoretic, and cyanotic immediately after summer football team practice in humid, 26.78C (808F) weather. The patient was admitted overnight 7 days before this presentation for treatment of exertional rhabdomyolysis. At that time, he complained of generalized muscle cramps after vigorous practice with peak creatinine 1.6 mg/dL, creatine kinase (CK) 1384 IU, and normal electrolytes. After a few days of rest, he resumed practice. He did not take any medications and had no surgical history. He strongly denied exposure to any performance- enhancing substances such as ephedra. In the emergency department, his rectal temperature was 42.28C. An endotracheal tube was placed secondary to altered mental status, and cooling measures, including nasogastric and bladder ice washes, fans, and a cooling blanket, were applied by emergency personnel while the patient was transported to the local emergency department. Initial vital signs included heart rate 168/min, respiratory rate 57/min, and blood pressure 146/103 mm Hg. His initial arterial blood pH was 7.33 with base deficit of 8.5 meq/L. Serum potassium was 5.9 meq/L, and CK was 785 IU. Two liters of normal saline were infused, and 500 mL of urine was collected in the first hour of treatment. Then the patient became oliguric. The intensive care unit physician supervising transport of this critically ill patient to the tertiary care facility requested treatment with sodium bicarbonate, calcium gluconate, kayexalate enema, administration of 4 more liters of normal saline, and dantrolene. After 1 hour of cooling measures, his rectal temperature was 38.08C, and blood pH and potassium were normal. Twenty-five milligrams of dantrolene, all that was available, (which contains 300 mg of mannitol/20 mg dantrolene per vial) and an additional 25 g of mannitol were given before transport to maintain temperature control and urine output. The patient was admitted to the pediatric intensive care unit with the diagnoses of heatstroke and exertional rhabdomyolysis. Computerized tomography of his head was normal, and 18 hours later, his mental status and pulmonary status had improved. The endotracheal tube was removed. He received oxygen via facemask without respiratory complication. To treat rhabdomyolysis and renal failure (creatinine 2.3 mg/dL), bicarbonate was added to his intravenous fluids to maintain urine pH above 7, and urine output was maintained at greater than 2 mL/kg per hour using furosemide and mannitol (3 g/h) infusions. On the second hospital day, fever returned to 398C, prompting resumption of dantrolene (1 mg/kg) every 6 hours intravenously. At this time, troponin I was found to be 9.2 ng/mL (normal < 0.08) with occasional inverted T waves on electrocardiogram. An echocardiogram showed normal findings. On the first hospital day, CK was 5947 IU. On the second day, it was 19,140 IU. On the third hospital day, CK peaked at 90,720 IU. Urine myoglobin reached a peak of 66,700 mg/L on the fourth hospital day. The patient met criteria for liver failure with a combination of impaired coagulation (peak prothrombin time, international normal- ized ratio, and partial thromboplastin time: 26.1, 2.3, and 33.7, respectively) and elevated liver function tests (peak aspartate transaminase 8682 U/L and alanine transaminase 7430 U/L). On the third hospital day, peak total and direct bilirubin of 7.5 mg/dL and 5.7 mg/dL, respectively, peak ammonia of 53 mg/dL, and thrombocytopenia (low 49,000/mL) on the fourth hospital day. These data prompted institution of plasma exchange and vitamin K treatment of disseminated intravascular coagulation (DIC) and multiple organ failure for 2 consecutive days. After consultation with the liver transplantation service, the patient received continuous fresh frozen plasma, alprostadil to dilate the hepatic vasculature, and lactulose until liver function approached normal. Results of plasma exchange were remarkable for resolution of coagulopathy, decrease in CK by 67%, aspartate transaminase and alanine transaminase by 88%, and gradual increase in platelet count by more than 100,000/ mL. Methylprednisolone was added on the fourth hospital day for a 7-day course based on preliminary animal studies showing increased survival benefits in heatstroke. Toxicology reports were positive for caffeine and negative for amphetamine, including ephedrine. Ampicillin-sulbactam, later changed to ceftazidime, was started on the third hospital day to treat a nosocomial urinary tract infection with Escherichia coli and Klebsiella pneumoniae. No fevers occurred after the third hospital day. Myoglobinuria was present until the tenth hospital day. Dantrolene was discontinued on the eighth hospital day and mannitol on the tenth hospital day without rebound of symptoms or worsening of laboratory studies. No adverse events were observed during the course of these medications. 510 Pediatric Emergency Care  Volume 22, Number 7, July 2006 Illustrative Case From the *Children’s Hospital of Pittsburgh, Pittsburgh, PA; yDepartment of Anesthesiology, University of Pittsburgh Medical Center, Pittsburgh, PA; and zMayo College of Medicine, Mayo Clinic, Jacksonville, FL. Supported by internal funding of the Department of Anesthesiology, UPMC. Address correspondence and reprint requests to Barbara W. Brandom, MD, North American Malignant Hyperthermia Registry, Department of Anesthesiology, Children’s Hospital of Pittsburgh, 3705 Fifth Avenue, DeSoto St, Room 7446, Pittsburgh, PA 15213. E-mail: bwb@pitt.edu. Copyright n 2006 by Lippincott Williams & Wilkins ISSN: 0749-5161/06/2207-0510 Copyr ight © Lippincott Williams & Wilkins. Unauthor iz ed reproduction of this article is prohibited.