急性肺损伤患儿氧交换指标动态监测的临床意义

目的　探讨急性肺损伤 (ALI)患儿的氧交换指标动态监测在临床的意义。方法　回顾性分析临床诊断ALI需呼吸支持的 33例患儿 ,根据其转归分为生存组和死亡组 ,分别在通气后 0 5h、2 4h、72h取动脉血做血气分析 ,并记录相同时点的吸入氧体积分数 (FiO2 ) ,以此计算不同时段的氧合指数 (PaO2 /FiO2 )、肺泡气 动脉血氧分压差 [P( A a)DO2 ]和动脉血氧分压 /肺泡氧分压(PaO2 /PAO2 )的数值。结果　生存组P(A a)DO2 在治疗 2 4h、72h后逐渐下降 ,与死亡组比较差异有显著性意义(P <0 0 5 ) ;PaO2 /FiO2 、PaO2 /PAO2 的数值变化在治疗 72h后才与死亡组比较差异有显著性 (2 4h ,P >0 0 5 ;72h ,P <0 0 5 )。PaO2 随治疗时间的推移 ,在生存组与死亡组间比较均无统计学意义 (P >0 0 5 )。提示PaO2 /FiO2 、PaO2 /PAO2 和P(A a)DO2 是对ALI早期治疗反应的敏感指标 ;PaO2 对预后的预警作用较为滞后。结论　在ALI呼吸支持患儿中 ,氧交换指标P(A a)DO2 、PaO2 /FiO2 和PaO2 /PAO2 更能反映肺损伤的程度 ,对预后的估计价值更大 ;动态监测氧交换指标可为临床预后的评估提供参考信息。

Monitoring oxygen exchange in children with acute lung injury

Objective To study the clinical significance of monitoring oxygen exchange in children with acute lung injury(ALI).Methods Thirty-three children with ALI needing mechanical ventilation were divided into two groups according to the outcome:the survival group( n =20) and the death group( n =13);0.5h,24h and 72h after mechanical ventilation,the arterial blood of all patients were extracted respectively,blood gas analysis was done and FiO_ 2 was recorded so as to calculate PaO_ 2 /FiO_ 2 ,and P(A-a)DO_ 2 ?PaO_ 2 /P_ A O_ 2 .Results In the survival group,the results of P(A-a)DO_ 2 were lower than that in the death group after 24h and 72h respectively( P <0.05).PaO_ 2 /FiO_ 2 and PaO_ 2 /P_ A O_ 2 showed difference between two groups only after 72h( P <0.05).As to the results of PaO_ 2 ,there was no significant difference between the two groups( P >0.05).Conclusion It indicates that P(A-a)DO_ 2 ,PaO_ 2 /FiO_ 2 and PaO_ 2 /P_ A O_ 2 are more sensitive than PaO_ 2 in the earlier treatment reaction.P(A-a)DO_ 2 ,PaO_ 2 /FiO_ 2 and PaO_ 2 /P_ A O_ 2 are better indices to reflect the degree of lung injury than PaO_ 2 .Monitoring the oxygen exchange is helpful for guiding treatment and prognosis.