新生儿呼吸衰竭时气体交换障碍及临床评估

The clinical evaluation of gas exchange impairment in neonatal respiratory failure

目的 探讨新生儿呼吸衰竭时发生气体交换障碍的机制。方法 采用血气分析、动脉 /肺泡氧分压比值 (PaO2 /PAO2 )、肺分流分数 (Q·s/Q·T)、动脉氧分压与吸入氧浓度之比 (PaO2 /FiO2 )、肺泡 动脉氧分压差 (A aDO2 )、呼吸指数 (RI)等多项指标 ,对 19931997年在我科NICU应用呼吸机治疗的 5 3例呼吸衰竭新生儿进行监测。结果 轻度呼吸衰竭组 (n =2 1)PaO2 /PAO2 比值 >0 2 2 ,Q·s/Q·T 为 (11± 3) % ,PaO2 /FiO2 比值为 (183± 113) ,A aDO2为 (2 2 9± 6 8)kPa ,RI(2 5± 0 8) ;重度呼吸衰竭组 (n =32 )PaO2 /PAO2 比值≤ 0 2 2 ,Q·s/Q·T 为 (2 4± 6 ) % ,PaO2 /FiO2 比值为 (82± 30 ) ,A aDO2 为 (4 9 3± 17 8) ,RI为 (7 6± 3 4) ;两组间有非常显著性差异 (P <0 0 0 1)。不同病因所致的呼吸衰竭其各项指标不同 ,以胎粪吸入组Q·s/Q·T 及A aDO2 最大 ,分别为 (32± 3) %和 (6 9 8± 12 2 )kPa,PaO2 /FiO2 最低 (77± 39) ,RI最高 (9 2± 2 9)。治愈组 (n =38)Q·s/Q·T 为 (17± 8) % ,而死亡组 (n =10 )Q·s/Q·T 高达 (2 4± 6 ) %。结论 应用这些指标对呼吸衰竭的新生儿进行临床评估 ,对认识病因、判断病情、指导治疗和估计预后有重要意义。

Objective To study the clinical evaluation of gas exchange impairment in neonatal respiratory failure.Methods Blood gas,PaO 2/P AO 2,Q· s/Q· T,PaO 2/FiO 2,A-aDO 2 and RI of 53 newborn infants with respiratory failure in NICU of PUMCH from Jan.1993 to Dec.1997 were measured.Results These infants were divided into two groups according to PaO 2/P AO 2:moderate and severe respiratory failure.Q· s/Q· T(11±3)%,PaO 2/FiO 2(183±113),A-aDO 2(229±68)kPa,RI(25±08)in 21 neonates with moderate respiratory failure;Q· s/Q· T(24±6)%,PaO 2/FiO 2(82±30),A-aDO 2(493±178)kPa,RI(76±34) in 32 neonates with severe respiratory failure(P<0001).These results in respiratory failure caused by different pathogenesis were different.In meconium aspiration and pneumothorax group there were the highestQ· s/Q· T(32±3)%,A-aDO 2(698±122)kPa,RI(92±29)and the lowest PaO 2/FiO 2(77±39).Mortality of infants with high pulmonary shunt was high.Q· s/Q· T(17±8)% in 38 survives and (24±6)% in 10 died neonates(P<005).Conclusion The clinical evaluation using these indexes for newborn infants with respiratory failure is beneficial in recognizing pathogenesis,guiding therapy and evaluating prognosis.