补充不同液体对5 km武装越野训练者内环境及机体热调节反应和重症中暑的影响

Effects of different fluid replenishment methods on internal environment,body thermal regulation response and severe heatstroke of 5-km armed cross-country training soldiers

目的探讨补充不同液体对5 km武装越野训练者内环境及机体热调节反应和重症中暑的影响。方法选择2018年6月至7月夏训期间参加5 km武装越野训练(每周2~3次,每次25~30 min,共3周)的某特战队官兵作为研究对象,并按随机数字表法将其分为3组,每组300例。各组分别于每次5 km武装越野训练前15 min、训练15 min后各补液200 mL,A组饮用白开水,B组饮用纯净水,C组饮用解放军联勤保障部队第九九○医院制剂室配制饮料(100 mL含碳水化合物6 g、钠42 mg、钾11 mg)。分别于训练前及最后一次训练后或重症中暑发病时立即取静脉血,检测血清心肌肌钙蛋白I(cTnI,化学发光法)、肌酸激酶同工酶(CK-MB,免疫抑制法)、血肌酐(SCr,酶法)、尿素氮(BUN,酶法)、丙氨酸转氨酶(ALT,比色法)、天冬氨酸转氨酶(AST,比色法)及Na^+、K^+、Cl^-含量(电极法),同时监测心率(HR)、核心温度(Tc,肛温);计算训练中出汗量并记录重症中暑发生情况。结果3组5 km武装越野训练前心、肝、肾功能及电解质、机体热调节反应情况差异均无统计学意义,具有可比性。与训练前比较,3组训练后或重症中暑发病时血清cTnI、CK-MB、SCr、BUN、ALT、AST水平及HR、Tc均明显升高,血清Na^+、K^+、Cl^-含量均明显下降,但C组较A组和B组升高或降低幅度相对较小〔cTnI(μg/L):0.9(0.6,1.4)比1.1(0.7,2.8)、1.0(0.6,3.3),CK-MB(U/L):7.0(5.0,11.0)比9.0(6.0,14.5)、8.0(6.0,15.0),SCr(μmol/L):92.09±18.64比102.78±18.77、103.64±20.07,BUN(mmol/L):7(6,9)比9(8,11)、10(8,13),ALT(U/L):27(22,34)比36(30,43)、34(27,43),AST(U/L):37(31,48)比41(34,50)、39(34,51),HR(次/min):87.01±17.07比95.88±21.06、96.59±22.04,Tc(℃):37.73±0.81比38.03±1.05、38.10±1.04,Na^+(mmol/L):150.14±3.86比144.18±8.89、144.04±9.39,K^+(mmol/L):4.32±0.57比4.15±0.62、4.13±0.51,Cl^-(mmol/L):100.43±3.71比98.42±4.24、98.41±4.58,均P<0.01〕。C组训练中重症中暑发生率较A组和B组显著降低〔1.67%(5/300)比5.00%(15/300)、5.33%(16/300),χ^2=6.424,P=0.040〕。A、B、C组训练中出汗量比较差异无统计学意义(g:370.47±48.71、370.85±50.66、370.17±50.21,F=0.014,P=0.986)。而A组与B组上述各指标比较差异均无统计学意义(均P>0.05)。二分类Logistic回归分析显示,HR、Tc的提高及Na^+、K^+、Cl^-的过度丢失是发生重症中暑的危险因素〔优势比(OR)分别为0.848、0.138、1.565、17.996、2.328,均P<0.01〕。结论及时补充碳水化合物、钠及钾能有效改变5 km武装越野训练者内环境、机体热调节反应,减少重症中暑。HR、Tc的提高及Na^+、K^+、Cl^-的过度丢失是发生重症中暑的危险因素。

Objective To explore the effects of different fluid replenishment methods on the internal environment,body thermal regulatory response and severe heatstroke of 5-km armed cross-country training soldiers.Methods A Special Force officers and soldiers who participated in 5-km armed cross-country training(2-3 times a week,25-30 minutes each time for 3 weeks)during summer training from June to July in 2018 were enrolled,and they were divided into three groups according to the random number table,with 300 trainees in each group.200 mL of drinking fluids were given to each group 15 minutes before and after each 5-km armed cross-country training:A group with boiled water,B group with purified water,and C group with beverage prepared by pharmaceutical laboratory of the 990th Hospital of PLA Joint Logistics Support Force(100 mL containing 6 g carbohydrates,42 mg sodium,and 11 mg potassium).The venous blood was collected before and after the last training or during the onset of severe heatstroke to do the following tests:serum cardiac troponin I(cTnI,chemiluminescence),MB isoenzyme of creatine kinase(CK-MB,immunosuppressive),serum creatinine(SCr,enzymatic method),urea nitrogen(BUN,enzymatic method),alanine aminotransferase(ALT,tryptase),aspartate transaminase(AST,tryptase),and Na^+,K^+,Cl^-(electrode method).The heart rate(HR)and core temperature(Tc,anal temperature)were monitored at the same time.The amount of sweat in training and the occurrence of severe heatstroke were also recorded.Results There was no significant difference in heart,liver,kidney function,electrolyte and body heat regulation reaction among three groups of 5-km armed cross-country trainees before training.Compared with before training,the levels of serum cTnI,CK-MB,SCr,BUN,ALT,AST,HR and Tc were significantly increased after training or during the onset of severe heatstroke in three groups,while the contents of Na^+,K^+,Cl^-were significantly decreased,but the increase or decrease of group C was relatively smaller compared with group A and group B[cTnI(μg/L):0.9(0.6,1.4)vs.1.1(0.7,2.8),1.0(0.6,3.3);CK-MB(U/L):7.0(5.0,11.0)vs.9.0(6.0,14.5),8.0(6.0,15.0);SCr(μmol/L):92.09±18.64 vs.102.78±18.77,103.64±20.07;BUN(mmol/L):7(6,9)vs.9(8,11),10(8,13);ALT(U/L):27(22,34)vs.36(30,43),34(27,43);AST(U/L):37(31,48)vs.41(34,50),39(34,51);HR(bpm):87.01±17.07 vs.95.88±21.06,96.59±22.04;Tc(℃):37.73±0.81 vs.38.03±1.05,38.10±1.04;Na^+(mmol/L):150.14±3.86 vs.144.18±8.89,144.04±9.39;K^+(mmol/L):4.32±0.57 vs.4.15±0.62,4.13±0.51;Cl^-(mmol/L):100.43±3.71 vs.98.42±4.24,98.41±4.58;all P<0.01].The incidence of severe heatstroke in group C was significantly lower than that in group A and group B[1.67%(5/300)vs.5.00%(15/300),5.33%(16/300),χ^2=6.424,P=0.040].There was no significant difference in sweating volume in groups A,B,C(g:370.47±48.71,370.85±50.66,370.17±50.21,F=0.014,P=0.986).There was no significant difference in the above indexes between group A and group B(all P>0.05).Bi-classification Logistic regression analysis showed that the increase of HR,Tc and excessive loss of Na^+,K^+,Cl^-were risk factors for severe heatstroke[odds ratio(OR)was 0.848,0.138,1.565,17.996 and 2.328 respectively,all P<0.01].Conclusions Timely supplementation of carbohydrate,sodium and potassium ions can effectively change the internal environment and body heat regulation reaction of 5-km armed cross-country trainees,so as to reduce the occurrence of severe heatstroke.The increases of HR,Tc and excessive loss of Na^+,K^+,Cl^-are risk factors for severe heatstroke.