单人高压氧舱对急进极高海拔地区人员肠系膜上动脉血流动力学的影响研究

Effects of single-person hyperbaric chamber on hemodynamics of superior mesenteric artery in personnel rushing to extremely high altitude area

目的 :研究单人高压氧舱对急进极高海拔地区人员肠系膜上动脉(superior mesenteric artery,SMA)血流动力学的影响。方法:选取由平原地区(海拔890 m)乘车前往极高海拔地区(海拔5 130 m)的健康青年男性受试者60例,随机分为对照组、低流量氧疗组和高压氧组,每组20例。进入高原地区后,对照组不作任何干预,低流量氧疗组每日通过鼻氧管供氧方式进行1次低流量氧疗(供氧流量为2 L/min,60 min/次),高压氧组每日利用单人高压氧舱进行1次高压氧治疗(增压压力为0.25 MPa,60 min/次)。分别在急进高原后第30天、第60天、第90天通过彩色多普勒超声诊断仪测量并比较3组受试者SMA主干及其1、2级分支动脉的收缩期峰值血流速度(peak systolic velocity,PSV)、阻力指数(resistance index,RI)和搏动指数(pulsation index,PI)。采用SPSS 19.0软件进行统计学分析。结果:急进高原30 d时,3组受试者SMA及其1、2级分支动脉PSV、RI、PI差异无统计学意义(P>0.05)。急进高原60 d时,对照组SMA及其1、2级分支动脉PSV显著高于低流量氧疗组与高压氧组,差异有统计学意义(P<0.05);低流量氧疗组与高压氧组SMA及其1、2级分支动脉PSV差异无统计学意义(P>0.05);3组间SMA及其1、2级分支动脉RI、PI差异无统计学意义(P>0.05)。急进高原90 d时,对照组SMA及其1、2级分支动脉PSV、RI、PI显著高于低流量氧疗组与高压氧组,差异有统计学意义(P<0.05);低流量氧疗组SMA及其1、2级分支动脉PSV显著高于高压氧组,差异有统计学意义(P<0.05),但2组间SMA及其1、2级分支动脉RI、PI差异无统计学意义(P>0.05)。结论:单人高压氧舱可显著改善机体因高原氧分压降低引起的SMA血流状态变化,对急进高原人员预防缺血性肠病的发生具有积极意义。

Objective To evaluate the effect of the single-person hyperbaric chamber on hemodynamics of superior mesenteric artery in the personnel rushing to the extremely high altitude area.Methods Sixty healthy young male subjects who traveled by car from the plains(890 m above sea level)to a very high altitude area(5130 m above sea level)were randomly divided into a control group,a low-flow oxygen therapy group and ahyperbaric oxygen group,with 20 cases in each group.Affer entering the plateau area,no intervention was made in the control group;in the low-flow oxygen therapy group,low-flow oxygen therapy was performed once a day by means of nasal oxygen cannula(oxygen flow rate of 2 L/min,60 min/times);in the hyperbaric oxygen group,hyperbaric oxygen therapy was carried out once a day in a single-person hyperbaric oxygen chamber(pressuri-zation pressure of 0.25 MPa,60 min/times).The subjects in the three groups had their peak systolic velocity(PSV),resistance index(RI),and pulsation index(PI)of the main trunks of the SMAs and their grade 1 and 2 branches measured and compared using color Doppler ultrasound diagnostic instruments on days 30,60,and 90,respectively,after acute entry to the plateau.SPSS 19.0 software was used for statistical analysis.Results There were no significant differences in PSV,RI and PI of SMA and its lst and 2nd grade branches between the 3 groups 30 days after entry(P>0.05).Sixty days after entry,the control group had the values of PSV statistically higher than those of the other two groups(P<0.05);there were no significant differences between the low-flow oxygen therapy group and the hyperbaric oxygen group in the values of PSV(P>0.05);the three groups had no obvious differences in the values of RI and PI(P>0.05).Ninety days after entry,the control group had the values of PSV,RI and PI all significantly higher than those of the other two groups(P<0.05);the low-flow oxygen therapy group had the values of PSV statistically higher than those of the hyperbaric oxygen group(P<0.05),while the values of RI and PI not significantly different from those of the hyperbaric oxygen group(P>0.05).Conclusion Single-person hyperbaric oxygen chamber significantly improves the SMA blood flow changes due to oxygen partial pressure reduction in the plateau,and thus is of significance for preventing ischemic enteropathy of the personnel rushing to the plateau.