肝硬化患者低动脉血氧分压和低动脉血二氧化碳分压的临床意义

Clinical Significance of Low Arterial Partial Pressure of Oxygen and Low Arterial Partial Pressure of Carbon Dioxide in Patients with Liver Cirrhosis

背景：肝硬化患者可合并多种脏器功能异常,其中肺功能异常临床并不少见,应引起重视。目的：探讨肝硬化患者低动脉血氧分压(PaO_2)和低动脉血二氧化碳分压(PaCO_2)与肝功能Child-Pugh分级的关系及其临床意义。方法：77例诊断明确的肝硬化患者纳入研究,其中Child-Pugh A级24例,B级29例,C级24例。行动脉血气分析以比较各级患者的PaO_2和PaCO_2。对低PaO_2血症者,予吸氧4h后复查动脉血气。结果：Child-Pugh A、B、C级肝硬化患者的低PaO_2血症和低PaCO_2血症发生率依次增高．PaO_2和PaCO_2检测值依次降低。三组低PaO_2血症的发生率分别为20．8％、48．3％和79．2％(P＜0．05)。PaO_2均值分别为10．72kPa±1．27kPa、9．85kPa±1．38kPa和9．13kPa±1．09kPa (P＜0．05)：低PaCO_2血症的发生率分别为29．2％、65．5％和91．7％(P＜0．05),PaCO_2均值分别为4．74kPa±0．64kPa、4．27kPa±0．54kPa和3．78 kPa±0．83kPa(P＜0．05)。低PaO_2血症者吸氧后低PaO_2血症显著改善(9．42kPa±0．84kPa对11．74kPa±0．86kPa,P＜0．01)．而低PaCO_2血症则未见改善(4．27kPa±0．34kPa对4．35kPa±0．46kPa,P＞0．05)。结论：低PaO_2和低PaCO_2是肝硬化患者存在肺功能异常的一项参考指标,并可能与肝损害程度有关。低PaCO_2并不是低PaO_2的继发结果,而可能是反映肝硬化患者肺功能异常的独立因素。

Background： Patients with liver cirrhosis are usually complicated by multiple organ dysfunction and pulmonary dysfunction is not rare, much concern should be paid. Aims： To appraise the clinical significance of low arterial partial pressure of oxygen （PaO2） and low arterial partial pressure of carbon dioxide （PaCO2） in cirrhotic patients and their relationship with Child-Pugh classification. Methods： 77 cirrhotic patients were enrolled in this study, among them, 24 were in Child-Pugh stage A, 29 in stage B and 24 in stage C. Arterial blood gas analysis were performed to evaluate PaO2 and PaCO2. Patients with lower PaO2 were given O2 for four hours, and then the PaO2 and PaCO2 were re-examined. Results： The incidence of lower PaO2 and PaCO2 increased and their values decreased when Child-Pugh staging descended （PaO2： 20.8%, 48.3% and 79.2%, respectively, P〈0.05, PaCO2： 29.2%, 65.5% and 91.7%, respectively, P〈0.05）. The mean values of PaO2 were 10.72 kPa±1.27 kPa, 9.85 kPa±1.38 kPa and 9.13 kPa±1.09 kPa, respectively （P〈0.05）. The mean values of PaCO2 were 4.74 kPa±0.64 kPa, 4.27 kPa±0.54 kPa and 3.78 kPa±0.83 kPa, respectively （P〈0.05）. In patients with lower PaO2, the PaO2 value improved remarkably after given O2 （9.42 kPa±0.84 kPa vs. 11.74 kPa±0.86 kPa, P〈0.01）, while their lower PaCO2 did not improved （4.27 kPa±0.34 kPa vs. 4.35 kPa±0.46 kPa, P〉0.05）. Conclusions： Lower PaO2 and lower PaCO2 can be used as complementary indices for pulmonary dysfunction in cirrhotic patients, and may be correlated with liver damage. Lower PaCO2 is not a phenomena secondary to lower PaO2, but may be an independent factor for pulmonary dysfunction in cirrhotic patients.