Headache, Nausea, Malaise ??? Triathlon

Abstract

1043 HISTORY: A 19 year-old female triathlete participating in a USA Triathlon sanctioned sprint distance event presented with a generalized, dull, achy-8/10 in severity headache, nausea with emesis, as well as generalized malaise 90 minutes after she crossed the finish line. Her past medical history includes controlled exercise induced bronchospasm, and seizure disorder for which she was taking carbamazepine. The outside temperature was 90+ degrees at race conclusion. She was a novice triathlete, but physically fit. Her race time of 1 hour and 33 minutes won her 1st Place in the Novice Division. She was asymptomatic during the race, and reported adequate fluid intake throughout the race. She also reported aggressive pre-race hydration and rehydration after the race's completion. Water was her fluid of choice for each of these. PHYSICAL EXAMINATION: Pulses were regular and symmetric with a rate of 70–80 bpm. Temperature 97OF orally. BP 128/82 without orthostatic change, respiratory rate 12/min; alert and oriented, equal and reactive pupils, intact extraoccular motion, intact tearing mechanism, moist mucus membranes and cool moist skin. Heart, lung, abdomen, and neurological exams were all normal. DIFFERENTIAL DIAGNOSIS: Hyponatremia Dehydration Heat Illness Exercise Induced Collapse Hypoglycemia Seizure Anticonvulsant toxicity TEST AND RESULTS: Pre-race Sodium 142 meq/L, (135–145), Carbamazepine 5.7 (4–10) 1 week prior. Post-race Na 127meq/L, K 3.5meq/L (3.3–5.1) glucose 87mg/dl (70–100), Creatinine 1mg/dL (0.6–0.9), BUN 10 mg/dL (6–21), and Serum Osmolality 254 mOsmol/L (275–295). Hemoglobin and Hematocrit 12.4 (12.0–15.5) and 36.0 (34.9–45). FINAL WORKING DIAGNOSIS: Hyponatremia, multifactorial. Dilutional and carbamazepine (SIADH) induced. TREATMENT AND OUTCOMES: EMS transportation to local emergency department. Gentle intravenous sodium correction with normal saline. Follow carbamazepine levels Education regarding future hydration during athletic events.