(P97) A Case of Severe Hyperthermia in the Setting of COVID-19 Infection

Chief Complaint : Seizure

History of Present Illness : A 33-year-old male with a history of asthma and multiple sclerosis with no current deficits presents for seizures. Approximately 30 minutes prior to arrival, the patient was found on the floor of his bedroom with seizure-like activity. In the Emergency Department (ED) he was unresponsive and noted to have left gaze deviation. He was treated with lorazepam and levetiracetam. However, he remained minimally responsive for hours. The family reported 3 days of fever, malaise, and headaches prior to arrival. The family denied any prior seizures or substance misuse. His medications were albuterol and fingolimod. A lumbar puncture was performed and antibiotics were given. Shortly afterwards, he aspirated and was intubated for airway protection with etomidate and rocuronium. Approximately one hour after intubation, his rectal temperature rose to 41.8°C.

Pertinent Physical Exam: The patient was unresponsive and had left gaze deviation. Initial vitals were temperature 36.4°C, heart rate 100, blood pressure 128/92, saturating 98% on room air with respiratory rate of 22. His pupils were 3 millimeters bilaterally and reactive. He did not have any witnessed seizure-like activity or myoclonic movements. He had no evidence of trauma on full exposure. After IV lorazepam and levetiracetam the gaze deviation resolved but he remained minimally responsive. His vitals were stable and he remained afebrile for several hours until intubation.

Pertinent Laboratory Data: On arrival, his capillary glucose was 199. Noncontrast CT of the head was unremarkable. Initial labs showed a venous pH of 7.22, pCO2 of 69 and a lactate of 5.2 mmol/L – all of which normalized with IV fluids. He was found to be COVID-postitive but otherwise labs, EKG, chest x-ray, urinalysis and urine drug screen were unremarkable. Bedside EEG was also done and did not show seizure activity. A lumbar puncture was performed with normal cell counts, glucose, and protein. His meningitis/encephalitis panel was negative.

Case Discussion: Within an hour of intubation, the patient experienced a hyperthermic emergency - a failing of the body’s temperature regulation mechanisms. This life-threatening emergency can lead to cardiac arrest and multiple-organ failure. No universal temperature definition exists but 40.5°C is often used specifically for heat stroke. (1)

Regardless of the etiology of severe hyperthermia, it is critical that immediate aggressive cooling measures, along with resuscitation (e.g. fluids, intubation), be initiated quickly to minimize end-organ damage. Ice water immersion is the superior method for cooling, with a rate of 0.20°C/min but can be intolerable for the patient or make monitoring difficult. Evaporative cooling can achieve 0.05°C/min. Core temperature should be continuously monitored and cooling should stop when it reaches 38-39°C to avoid hypothermia. (2,3)

Due to the patient’s prolonged period of stability prior and the temporal relationship of decompensation to the intubation, malignant hyperthermia (MH) was a primary differential. Other causes of hyperthermic emergencies such as sympathomimetic or anticholinergic overdose, neuroleptic malignant syndrome, serotonin syndrome, and heat stroke were unlikely. (2) In addition, multiple sclerosis patients are more prone to thermal dysregulation. (4) Rarely, rocuronium has been implicated as a cause of MH. (5) Treatment of MH includes dantrolene, which reduces muscle contraction and heat generation through inhibition of calcium release from the sarcoplasmic reticulum. (6)

After recognition of this temperature, the patient was placed in a bag filled with ice and water under constant temperature monitoring. Dantrolene was given and his antibiotics were broadened. He was admitted to the intensive care unit where he was diagnosed with COVID myocarditis based on a newly reduced ejection fraction, troponemia and ST-elevations. Overall his presentation was thought to be due to severe COVID and autonomic dysfunction from multiple sclerosis. Despite severe illness, with supportive care he made a full neurologic recovery.

References and Acknowledgements (Optional): [1] Epstein, Y., Yanovich, R. Heatstroke. N. Engl. J. Med. 380, 2449–2459 (2019).
[2] Smith JE. Cooling methods used in the treatment of exertional heat illness. British Journal of Sports Medicine. 39, 503-507 (2005).
[3] Sorensen C, Hess J. Treatment and Prevention of Heat-Related Illness. N Engl J Med. 387, 15, 1404 (2022).
[4] Razi O, Tartibian B, Teixeira AM, Zamani N, Govindasamy K, Suzuki K, Laher I, Zouhal H. Thermal dysregulation in patients with multiple sclerosis during SARS-CoV-2 infection. The potential therapeutic role of exercise. Mult Scler Relat Disord. 59, 103557 (2022).
[5] Ashton E. Beggs, Pharm.D., Jennifer Quinn McCann, Pharm.D., BCPS, Jan M. Powers, Ph.D., RN, CCRN, CCNS, CNRN, FCCM, Delayed-onset malignant hyperthermia in association with rocuronium use, American Journal of Health-System Pharmacy. 69, 13, 1128-34 (2012).
[6] Wappler, F.. Malignant hyperthermia. European Journal of Anaesthesiology 18,10, 632-652, (2001).