Serum procalcitonin levels are associated with rhabdomyolysis following exertional heatstroke: an over 10-year intensive care survey / 世界急诊医学杂志（英文）

@#BACKGROUND: Heatstroke has become a common emergency event in hospitals. Procalcitonin (PCT) is used as a biomarker of infection in the emergency department (ED), but its role in rhabdomyolysis (RM) following exertional heatstroke (EHS) remains unclear. METHODS: A retrospective cohort study enrolled patients with EHS from the intensive care unit (ICU). We collected RM biomarkers, inflammation markers, critical disease scores at admission, 24 h, 48 h, and discharge, and 90-day mortality. Correlation analysis, linear regression and curve fitting were used to identify the relationship between PCT and RM. RESULTS: A total of 162 patients were recruited and divided into RM (n=56) and non-RM (n=106) groups. PCT was positively correlated with myoglobin (Mb), acute hepatic injury, disseminated intravascular coagulation (DIC), Sequential Organ Failure Assessment (SOFA) score, and Acute Physiology and Chronic Health Evaluation II (APACHE II) score, with correlation coefficients of 0.214, 0.237, 0.285, 0.454, and 0.368, respectively (all P<0.05). Interestingly, the results of curve fitting revealed a nonlinear relationship between PCT and RM, and a two-piecewise linear regression model showed that PCT was related to RM with an odds ratio of 1.3 and a cut-off of <4.6 ng/mL. Survival analysis revealed that RM was associated with higher mortality compared to non-RM cases (P=0.0093). CONCLUSION: High serum PCT concentrations are associated with RM after EHS in critically ill patients. Elevated PCT concentrations should be interpreted cautiously in patients with EHS in the ED.

Preventive oral rehydration salts Ⅲ could protect intestinal function in rats with exertional heatstroke / 中华危重病急救医学

Objective To observe the damage of various organs of rats with exertional heatstroke (EHS), and to investigate the protective effect of oral rehydration salts Ⅲ (ORSⅢ) on multi-organ function in rats with EHS. Methods Fifty-one male Sprague-Dawley (SD) rats were randomly divided into four groups by random digit table: normal control group (n = 13), EHS group (n = 13), EHS+water group (n = 12), and EHS+ORSⅢ group (n = 13). All rats in the EHS groups received adaptive training for 7 days before the experiment. On the 8th day, the rats of EHS+water and EHS+ORSⅢ groups were orally given 20 mL/kg water or ORSⅢ 30 minutes before the experiment. No pretreatment was performed in the EHS group. EHS model was reproduced by forcing rats to run under hot environment. The rats which refused to exercise and which core temperature > 40.5 ℃ were considered as the onset of EHS. The rats in the normal control group were exposed to room temperature (25±2) ℃ and humidity (50±5)% without any treatment. Six hours later, blood of inferior vena cava was collected, and the levels of serum MB isoenzyme of creatine kinase (CK-MB), lactate dehydrogenase (LDH), alanine transaminase (ALT), aspartate transaminase (AST), serum creatinine (SCr), blood urea nitrogen (BUN), serum potassium, serum sodium and serum chloride were determined by automatic chemical analyzer. Serum intestinal fatty acid-binding protein (I-FABP) was determined by enzyme linked immunosorbent assay (ELISA). Results The levels of LDH, ALT, AST, BUN, serum sodium and serum chloride in the EHS group were significantly higher than those in the normal control group [LDH (U/L): 1 220±427 vs. 837±485, ALT (U/L): 138 (97, 164) vs. 37 (33, 42), AST (U/L): 409 (380, 566) vs. 86 (78, 104), BUN (mmol/L): 11.7 (9.6, 13.2) vs. 5.9 (5.5, 6.1), serum sodium (mmol/L): 148.0 (143.5, 154.5) vs. 139.0 (138.0, 140.5), serum chloride (mmol/L): 100.9±2.3 vs. 97.3±1.4, all P < 0.05], but no significant difference in CK-MB, SCr or serum potassium could be found [CK-MB (U/L): 1 280±373 vs. 1 379±480, SCr (μmol/L): 38.2±7.5 vs. 35.5±6.3, serum potassium (mmol/L): 5.5 (4.4, 6.2) vs. 4.7 (4.4, 4.9), all P > 0.05]. In the EHS+ORSⅢ group, only serum potassium level was significantly lower than that in the EHS group [mmol/L: 4.0 (3.7, 4.4) vs. 5.5 (4.4, 6.2), P < 0.01], while no significant difference in other parameters was found between the EHS+ORSⅢ group and the EHS group as well as the EHS+water group. Serum I-FABP level in the EHS group was significantly higher than that in the normal control group [μg/L: 36.90 (29.10, 45.00) vs. 11.39 (0.31, 20.80), P < 0.01]. Serum I-FABP level in the EHS+water and EHS+ORSⅢ groups were notably lower than that in the EHS group [μg/L:24.19 (20.00, 28.36), 0.31 (0.31, 5.58) vs. 36.90 (29.10, 45.00), both P < 0.01], additionally, I-FABP level was much lower in the EHS+ORSⅢ group (P < 0.01). Conclusions EHS could lead to liver, intestinal barrier dysfunction and electrolyte disturbance. Pre-treatment of ORSⅢ could alleviate the intestinal dysfunction and electrolyte disorder caused by EHS in rats. It can lower the serum potassium to some extent. However, ORSⅢ failed to protect liver from EHS.

Effect of early intervention with heparin on function of coagulopathy, liver and kidney in rats with exertional heatstroke under the ambient air of high temperature and low humidity / 中华危重病急救医学

Objective To explore the effects of early intervention with heparin on function of coagulopathy, liver and kidney as well as the prognosis in rats with exertional heatstroke (EHS) under the ambient air of high temperature and low humidity. Methods 108 healthy SPF male Sprague-Dawley (SD) rats were randomly divided into normal temperature control group, EHS + normal saline (NS) group and EHS + heparin group. Of which 54 rats were collected for survival analysis (18 rats in each group), the weight change and 8-hour survival rate were observed,and Kaplan-Meier survival curves were drawn. Other 54 rats were collected for intervention experiment, the rats in each group were subdivided into 0, 1, 2 hours subgroups according to the time points of intervention with heparin after model reproduction, with 6 rats in each subgroup. The rats were placed in an artificial experiment cabin with northwest special environment, and the temperature and the relative humidity were (25.0±1.0) ℃ and (35±5)%, respectively, in normal temperature control group, and the rats were not treated in the cabin. The rats in EHS + NS group and EHS + heparin group kept running in the cabin which temperature and relative humidity were set at (43.0±0.5)℃ and (35±5)% until the anus temperature of rats reached 43.0 ℃, and then the rats were placed in room temperature. The rats were injected with 1 mL/kg NS or 250 U/kg heparin sodium injection through their caudal veins at 0, 1, and 2 hours, respectively, and then the blood was collected after 1.5 hours to determine the biochemical parameters including coagulation, liver and kidney as well as platelet count (PLT). Results ① The weight loss of EHS + NS group and EHS + heparin group was more significant than that of normal temperature control group (g: 8.28±1.41, 8.39±1.38 vs. 2.06±1.06, both P < 0.05), but there was no significant difference between EHS + NS group and EHS + heparin group. ② As the time went on after modeling, serum creatinine (SCr), blood urea nitrogen (BUN), alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase (CK), activated partial thromboplastin time (APTT), and D-dimer of EHS rats showed a tendency of increasing, but fibrinogen (FBG), antithrombin Ⅲ (ATⅢ) and PLT were decreased gradually, which were obviously abnormal as compared with those at corresponding time point of the normal temperature control group. Heparin intervention 0 hour after modeling could improve the function of liver and kidney, FBG, D-dimer, ATⅢ and PLT, but APTT was prolonged further. The SCr, BUN, ALT, AST and CK in EHS 2 hours + heparin group were still better than EHS + NS group [SCr (μmol/L): 93.33±7.69 vs. 110.50±13.56, BUN (mmol/L): 20.55±1.35 vs. 24.88±2.41, ALT (U/L): 322.17±36.36 vs. 492.33±64.19, AST (U/L): 1 252.33±240.86 vs. 2 725.67±461.17, CK (U/L):1 4628.67±2 784.68 vs. 2 6843.00±2 637.16, all P < 0.01], APTT was significantly prolonged (s: 51.83±6.11 vs. 33.83±4.31, P < 0.01), and ATⅢ and PLT were significantly increased [ATⅢ: (78.03±9.15)% vs. (64.28±12.55)%, PLT (×109/L): 457.67±32.33 vs. 415.83±26.45, both P < 0.05], however, there was no obvious influence on FBG or D-dimer. ③ The rats in normal temperature control group were all survived within 8 hours, and all dead in EHS + NS group. The survival rate of rats given heparin intervention at 0, 1, 2 hours after successfully modeling was 50.0%, 33.3% and 0%, respectively. Kaplan-Meier survival curve analysis showed that 8-hour cumulative survival rate in EHS 0 hour, 1 hour + heparin groups was higher than that in EHS 0 hour, 1 hour + NS groups (χ12 = 7.930, P1= 0.005; χ22 = 4.408, P2= 0.036), however, there was no significant difference between EHS 2 hours + heparin group and EHS 2 hours + NS group (χ2= 2.660, P = 0.103). Conclusion Early heparin intervention can improve the coagulation function and organ function of EHS rats, while improving the survival rate of rats, indicating the earlier intervention of heparin, the better prognosis of rats is.

Imersão em água fria para o manejo da hipertermia severa / Cold water immersion to the control of exertional heat illness

A incapacidade de dissipar o calor gerado pela atividade muscular prejudica o desempenho e aumenta a predisposição a lesões do organismo. A hipertermia severa induzida pelo esforço físico (HTE) prejudica a saúde e está associada à morbidade e mortalidade de indivíduos em diferentes atividades ocupacionais e atléticas. Estudos sobre a eficiência de métodos de resfriamento corporal têm recomendado a imersão em água fria para o tratamento da HTE. Sua utilização nos minutos iniciais pós-hipertemia parece a melhor recomendação por reduzir o tempo no qual a temperatura central permanece elevada. A manutenção de infraestrutura necessária para a realização desse procedimento deve ser considerada em atividades físicas e condições ambientais nas quais os indivíduos estão mais suscetíveis ao acometimento da HTE. As taxas de resfriamento observadas através da imersão em água a diferentes temperaturas podem servir de referência para o controle da duração do procedimento. Esta revisão analisa a recomendação da imersão em água fria como procedimento de resfriamento corporal para o manejo da HTE.

The incapacity of dissipating heat generated by muscular activity hampers performance and increases predisposition to physical injuries. Exertional heat illness (HTE) harms health and is associated with morbidity and mortality of individuals in different occupational and athletic activities. Studies on the efficiency of body cooling methods have recommended cold-water immersion for the treatment of HTE. Its use in the initial minutes of post-hyperthermia seems to be the best recommendation to reduce the time central temperature remains high. Maintenance of the infrastructure needed to perform this procedure should be considered in physical activities and environmental conditions in which the individuals are more prone to HTE. The cooling rates observed through water immersion in different water temperatures may serve as reference to the control of HTE procedure duration. This review analyses the recommendation of cold-water immersion as a body cooling procedure for management of HTE.

Insuficiência hepática fulminante por intermação induzida por exercício / Fulminant hepatic failure (FHF) by exercise-induced exertional heatstroke

Intermação induzida por exercício é uma condição potencialmente fatal causada pela elevação extrema da temperatura corporal central. Envolvimento hepático leve a moderado afeta todos os pacientes e manifesta-se pela elevação das enzimas hepáticas. A ocorrência de falência hepática no curso da intermação por exercício é rara e tem prognóstico reservado. Relata-se um caso de insuficiência hepática fulminante em um homem de 36 anos após correr 8km em corrida de rua (corrida rústica) na cidade de Manaus (AM). O paciente desenvolveu insuficiência renal aguda, rabdomiólise e achados compatíveis com insuficiência hepática fulminante (elevação importante das aminotransferases, coagulopatia, letargia e episódios de confusão). As funções hepáticas e renais apresentaram melhora gradual e espontânea sem necessidade de diálise. Três meses após o paciente encontrava-se bem, com enzimas hepáticas normais e com retorno gradual à prática de esportes. Embora rara, a falência hepática aguda deve ser incluída nas complicações da intermação induzida por exercício, a qual pode ter resolução espontânea com medidas conservadoras.

Exercise-induced exertional heatstroke (EHS) is a potentially fatal disorder caused by extreme elevation of the core body temperature. Mild to moderate liver involvement affects nearly all patients and it is manifested by increase of the serum liver enzymes. Liver failure occurring as a component of exertional heatstroke is rare and carries a poor prognosis. A case of acute liver failure in a healthy 36 year-old man after participation in an 8-km race in Manaus, located near the Amazon Tropical Forest in Brazil, is reported here. The patient presented renal failure, severe rhabdomyolysis and findings of fulminant hepatic failure (very high aminotransferases levels, elevated international normalized ratio (INR), lethargy and episodes of confusion). Hepatic and renal functions improved spontaneously with conservative measures and he was discharged within eight days. Three months later he was completely asymptomatic and gradually running again. Although rare, acute liver failure should be included in the complications associated with exertional heatstroke. Conservative management may be effective in some patients with this kind of acute liver failure.