新生儿急性呼吸衰竭呼吸机撤离时的呼吸力学研究

The measurement of respiratory mechanics and its clinical significance in newborns weaning from mechanical ventilation

目的探讨新生儿机械通气撤机时呼吸力学指标的范围及临床意义。方法测定32例机械通气撤机时,新生儿在持续气道正压(CPAP)模式、脱机拔管前及拔管后20min等条件下的呼吸力学指标范围。根据拔管48h内是否重新插管,将以上病例分为撤机成功组与失败组。结果成功组的呼吸力学范围:平均气道阻力(Rawmean)为(93．7±14．3)cmH2O／(L·S)(1cmH2O=98．07Pa)、呼吸系统顺应性(Crs) 为(0．65±0．09)ml／(cmH2O·kg)、呼吸功(WOBp)为(1589±133．2)g·cm／(min·kg);失败组:Rawmean 为(98．6±15．5)cmH2O／(L·S)、Crs为(0．57±0．08)ml／(cm H2O·kg)、WOBp为(1782±148．6)g· cm／(min·kg)。Crs与WOBp两组差异有显著意义(P<0．05),脱机成功率为95．4％。结论呼吸力学的检测对新生儿呼吸机的撤离有指导作用,特别是对呼吸系统顺应性和呼吸功的检测,更具有实际意义。

Objectives To explore the range of respiratory mechanics values on weaning ventilators in mechanical ventilated newborns and its clinical significance. Methods Thirty-two ventilated newborns were measured for indices of respiratory mechanics using a Bicore CP-100 pulmonary monitor under a continuous positive airways pressure of 3cmHzO, and in the periods of pre-extubation after ventilator weaning and 20 min post-extubation. Extubation success was defined as no reintubation within 48 hours of extubation. Results In the extubation success group, Rawrnean （mean airway resistance） was （93. 7±14. 3）emH2O/（L · S）, Crs（respiratory system compliance） （0. 65±0. 09） ml/（emH2O · kg）, WOBp （work of breathing, patient ）（1589±133.2） g · cm/（min · kg） ;in the extubation failure group, Rawrnean （98.6±15.5）emH20/（L · S）, Crs（0. 57±0.08）ml/（cmH2O · kg）, WOBp（1782± 148.6） g · cm/（min · kg）. There were significant differences between the two groups in Crs and WOBp. The rate of successful weaning was 95.4%. Conclusion Bedside measurements of improved respiratory mechanics （WOBp,Crs） can be used to predict the outcome of mechanical ventilation withdrawal in neonates. Pulmonary function testing may help choose the optimal time for extubation in infants.