单肺通气模式对阻塞性通气障碍患者气道峰压、氧合作用及肺内分流的影响

Effects of one-lung ventilation on the peak airway pressure,arterial oxygenation and intrapulmonary shunt in patients with obstructive ventilatory disorder

目的观测阻塞性通气障碍患者在单肺通气(OLV)期间用压力控制通气(PCV)与容量控制通气(VCV)对气道峰压(Ppeak)、氧合作用和肺内分流(Qs/Qt)的影响。方法择期行右侧开胸成年手术患者30例,ASAⅠ～Ⅲ级,按术前肺功能分为2组,N组为肺功能正常患者,O组为阻塞性通气障碍患者。再根据OLV模式将每组随机分为2个亚组,N-PCV组和N-VCV组各8例,O-PCV组和O-VCV组各7例。丙泊酚-瑞芬太尼-罗库溴铵静脉诱导后插入左双腔支气管导管,行双肺VCV,潮气量7～8ml/kg,呼吸频率15次/min。30min后改左侧卧位行左OLV。N-VCV组和O-VCV组先行VCV30min,然后改行PCV30min。N-PCV组和O-PCV组先行PCV30min,然后改行VCV30min。OLV-VCV期间拟定的潮气量及呼吸频率维持不变;压力设定以达到双肺VCV期间潮气量为准。双肺VCV后30min及OLV后30、60min进行血气分析,计算Qs/Qt。结果OLV期间,N-PCV组和O-PCV组的Ppeak较N-VCV组和O-VCV组低(P<0.01),但PaO2和Qs/Qt差异无统计学意义(P>0.05)。结论阻塞性通气障碍患者OLV期间采用PCV更有利于减低气道压,但对动脉氧合作用及肺内分流的改善不明显。

Objective To compare the effects of pressure-controlled ventilation （PCV） with volume controlled ventilation （VCV） on peak airway pressure （Ppeak）, arterial oxygenation and intrapulmonary shunt （Qs/Qt） in patients with obstructive ventilatory disorder during one-lung ventilation （OLV）. Methods Thirty ASA physical status Ⅰ to Ⅲ patients undergoing elective right thoracotomy were enrolled. According to the preoperative pulmonary function, the patients were divided into two groups, group N with normal pulmonary function and group O with obstructive ventilatory disorder, then which were randomly subdivided into group N-VCV （ n = 8）, group N-PCV （ n = 8）, group O-VCV （ n = 7）, and group O-PCV （ n = 7） according to different OLV modes. Anesthesia was induced and maintained intravenously with propofol, remifentanil and rocuronium, a left-sided double-lumen endobroncheal tube （DLT） was inserted. After two-lung ventilation with VCV for 30rain with tidal volume of 7 - 8 ml/kg and respiratory rate of 15 breaths/rain, the patients were turned to the left lateral decubitus position and converted to left OLV. The patients in group N-VCV and group O-VCV were initiated with VCV （OLV-VCV） with the above respiratory variables for 30min and switched to PCV for 30min, the inspiratory pressure during PCV was adjusted to maintain the same tidal volume as during VCV. The modes of ventilation were performed in the opposite order in those of group N-PCV and group O-PCV. At the end of each 30-minute ventilation stage, arterial and mixed venous blood samples were taken for blood gas analyses and Qs/Qt calculations, and Ppeak were recorded. Results The Ppeak was significantly decreased during OLV with pressure-control ventilation, as compared to those with volume-control ventilation （ P 〈0.01 ）. But there were no differences during OLV in arterial oxygenation and Qs/Qt between VCV and PCV in group N and group O（ P 〉0. 05）. Conclusion As compared with VCV, PCV during OLV conduces a lower Ppeak for patients with obstructive ventilatory disorder, but which could not obviously improve arterial oxygenation and Qs/Qt.