摘要
目的 探讨允许性高碳酸血症（PHC）对急性呼吸衰竭新生猪机械通气时脑血流及组织代谢的影响.方法 18只新生猪随机（随机数字法）分为PHC组、标准碳酸血症（NC）组、健康对照组（Control）;PHC（PaCO250～60 mmHg）与NC组（PaCO2 35～45 mmHg）以胎粪致急性呼吸衰竭,机械通气;每组6只.应用彩色微球示踪技术,测定脑组织血流速度（CBF）,脑组织氧代谢率（CMRO2）、脑组织糖代谢率（CMRGlu）、脑组织乳酸生成率（CLP）.结果 NC组新生猪在机械通气6 h,12 h时点CBF较Control组显著降低（P＜0.05）;12 h时点CMRGlu及CLP较Control组升高,CMRO2较Control组降低;CBF/CMRGlu及CBF/CLP比值在6 h及12 h均较Control组降低（P＜0.05）.NC组CBF/CMRO2与Control组相比,差异具有统计学意义（P＞0.05）.PHC组在6 h CBF较Control组降低;12h时点,PHC组CBF与Control组相比,差异无统计学意义;PHC组各时点CMRO2,CMRGlu,CLP与Control组相比,差异均无统计学意义.CBF/CMRGlu及CBF/CLP比值在机械通气6 h,12 h时点,PHC组低于Control组,但与NC组相比,下降程度已减少（P＜0.05）;PHC组CBF/CMRO2与Control组相比,差异无统计学意义.结论 急性呼吸衰竭新生猪予正常碳酸血症水平机械通气时,CBF降低,存在脑血流-代谢调节障碍.PHC可减轻CBF下降,改善急性呼吸衰竭新生猪在正压通气时的脑血流-代谢调节障碍.
Objective To investigate the effects of permissive hypercapnia （PHC） strategy used in ventilated newborn swine with respiratory failure on cerebral blood flow （CBF） and tissue metabolism. Method Eighteen newborn swine were randomly （random number） divided into 3 groups （n = 6）： PHC, normocapnia （NC） and normal control groups. In PHC （PaCO2 50～60 mmHg） and NC （PaCO2 35 ～ 45 mmHg） groups, newborn swine were ventilated for treating respiratory failure induced by meconium aspiration. CBF was measured by using colored microsphere tracking technique. Cerebral oxygen metabolism rate （CMRO2）, cerebral glucose metabolism rate （CMRGlu）, and cerebral lactate production （CLP） were measured. Results After ventilation for 6 hours and 12hours, CBF in NC group decreased more significantly than those did in control group, and CMRGlu and CLP increased more significantly than those did in control group. In NC group, CMRO2 decreased more prominently than it did in control group 12 hours later. The CBF/CMRGlu and CBF/CLP ratios in NC group were lower than those in control（P〈0.05）. There was no significant difference in CBF/CMRO2 ratio between NC and control groups. After ventilation for 6 hours, CBF in PHC group was lower than those in control group. But after ventilation for 12hours, CBF in PHC group increased and there was no significant difference in CBF between PHC group and control group （P〉O.05）. There were no significant differences in CMRGlu, CLP and CMRO2 between PHC group and control group. The CBF/CMRGlu and CBF/CLP ratios in PHC group were lower than those in control, but higher then those in NC group （P〈0.05）. There was no significant difference in CBF/CMRO2 ratio between PHC and control groups. Conclusions The reduction of cerebral blood flow and the disturbance of CBF autoregulation disturbance occur in ventilated newborn swine with hypoxemia respiratory failure. PHC may attenuate the reduction in CBF and the disturbance of CBF autoregulation.
出处
《中华急诊医学杂志》
CAS
CSCD
北大核心
2011年第1期44-47,共4页
Chinese Journal of Emergency Medicine
基金
上海市教委资助项目（06BZ054）
关键词
允许性高碳酸血症
机械通气
脑
血流速度
猪
新生
Permissive hypercapnia
Mechanical ventilation
Cerebral
Blood flow
Swine
Newborn
