The Pattern Of Change In Blood Biomarkers In Exertional Heat Stroke Patients During Hospitalization

Exertional heat stroke (EHS) is a life-threatening medical condition characterized by extreme hyperthermia and multi-organ dysfunction. EHS prognosis depends on the temperature-time area above a critical temperature (40oC). Thus, the customary practice of treatment is aggressively cooling the patient prior to evacuation to ER, arriving at the hospital with a body core temperature lower than 40oC. This may lead to misdiagnosis of EHS and early discharge from hospitalization. Even if EHS is suspected there is a tendency to release the patient from hospitalization when biochemistry analysis in the ER is circa normal values. PURPOSE: To follow the change in biochemical profile during the first 84 hrs. after collapse, to reflect the dynamics in organ’s dysfunction. METHODS: Case series of 6 consecutive EHS patients who were hospitalized for at least 84 hrs. Biomarkers reflecting the inflammatory system, muscle breakdown, liver function, kidney function, coagulation, and sodium levels have retrospectively been investigated, to create a trend reflecting the biomarkers’ dynamics in EHS patients. RESULTS: On average, the levels of all biomarkers were impaired upon admission to the ER, but with a wide range, as depicted in the table. The true dynamics in the levels of the biochemical profile, reflecting organ disfunction, starts to be clear after 24-48 hrs. Only then, an impairment in liver function, kidney or coagulopathy could be established. - Biomarker Time (hrs.) Referencevalues 0 24 36 48 72 84 WBC(/μL3) 14.9-29.3 8.2-14.8 7-12.3 5.2-10.3 6.4-7.6 7.1-10.0 4.5-11.0 Platelets(/μL3) 213-463 127-197 171-189 162-277 150-450 CPK (X102) (U/L) 4-18 22-1094 13-607 9-341 5-225 24-198 <2 (X102) LDH(U/L) 100-1346 563-2000 395-1303 549-986 465-855 466-802 140-280 AST(U/L) 36-157 64-1751 62-1179 38-741 25-476 171-470 14-20 ALT(U/L) 23-63 29-428 26-419 28-347 25-322 213-362 4-36 Creatinine(mg/dL) 1.6-5.3 0.9-2.9 0.7-0.8 0.8-3.2 0.8-2.6 0.7-0.8 0.7-1.2 Urea(mg/dL) 42-56 16-31 18-56 5-56 21-22 17-23 Sodium(mEq/L) 129-143 140-143 139-140 139-145 140-143 139-141 135-145 CONCLUSION: The biochemical picture upon admission to the ER can be misleading in the diagnosis of EHS and its sequalae. Because the dynamics varies between patients, and the initial laboratory presentation does not reflect the complete end-organ damage, we recommend hospitalizing EHS patients for 96 hours and no less than 48 hrs., and to follow the dynamics of biomarkers change at a 12 hrs. interval, before a decision is taken on the outcome and the release from hospitalization.