Author: Sarah Robinson, DO
Senior Editor: Heather Rainey, MD
Editor: Amanda Phillips, MD, MPH

Patient Presentation:
A 25-year-old NCAA Division I hockey goalie with a history of malignant hyperthermia presented to the emergency department following an acute episode of excessive sweating, full-body cramping, and temporary loss of consciousness during a hockey game.
During the game, the patient initially experienced intermittent cramping in the first and second periods, which progressed to sustained cramping in the third period. By the end of the game, the cramping had spread throughout his body, leaving him unable to walk or stand. He subsequently experienced a syncopal episode lasting approximately 30 seconds, displaying postictal-like symptoms upon recovery. EMS responded, initiating care with two large-bore IVs and transporting him to the emergency department for further management.

History:
The patient has a long history of excessive sweating that began around age 14 and has progressively worsened during his collegiate hockey career. Although he does not experience excessive sweating at rest, he reports feeling cold throughout the day. With physical activity, he sweats profusely, often losing up to 10 pounds in sweat during intense sessions. If he does not promptly rehydrate with electrolytes, he experiences dehydration, chills, and escalating muscle cramps throughout his body.
His medical history includes two hospitalizations for rhabdomyolysis, one of which required intensive care unit (ICU) admission due to renal failure and CK levels exceeding 10,000 U/L. Following these episodes, he was referred to the Korey Stringer Institute for electrolyte testing.
Pre-participation physical exams performed by his team physician have been within normal limits. However, in January 2024, the patient experienced a similar cramping episode during a game, resulting in another emergency department visit.

Physical Exam:
Vital Signs: BP 140/75 mmHg, Pulse 120 bpm, O₂ Sat 99%
General: Acute distress with full-body cramping that spread from the legs to the lower back, arms, and neck
Neurologic: Alert but disoriented (oriented x1); 30-second syncopal episode with postictal-like symptoms
Musculoskeletal: Decreased range of motion in all extremities; unable to walk due to severe cramping
Respiratory: Lungs clear to auscultation; no wheezing, rales, or rhonchi
Cardiac: Tachycardia with regular rhythm, normal S1/S2 sounds, and no murmurs
Skin: Flushed face, excessive diaphoresis pooling beneath him, and epistaxis

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