肝肺综合征患者对症状限制性运动的反应。

Epstein S K, Zilberberg M D, Jacoby C, Ciubotaru R L, Kaplan L M

Department of Medicine, Tupper Research Institute, New England Medical Center, Tufts University School of Medicine, Boston, MA 02166, USA.

Chest. 1998 Sep;114(3):736-41. doi: 10.1378/chest.114.3.736.

OBJECTIVE

To study the response to symptom-limited exercise in patients with the hepatopulmonary syndrome (HPS).

DESIGN

The response to maximal cardiopulmonary exercise (CPX) was studied in 5 patients with HPS and compared with 10 case control (normoxemic, NC) cirrhotics (matched for age, gender, etiology and severity of liver disease, tobacco use, and beta-blocker therapy) and 9 hypoxemic control cirrhotics (HC) without clinical evidence of HPS.

SETTING

Cardiopulmonary exercise physiology laboratory in a tertiary care referral center.

PATIENTS

Cirrhotics referred for CPX as part of their preliver transplantation evaluation.

MEASUREMENTS

Standard pulmonary function tests and echocardiography were performed to assess resting pulmonary and cardiac function. Peak oxygen consumption (VO2), minute ventilation, arterial blood gases, and dead space (VD/VT) were determined during symptom-limited maximal CPX.

RESULTS

Resting spirometry and lung volumes were similar between HPS and NC subjects, while HC subjects had restrictive physiology. Differences existed in diffusing capacity corrected for hemoglobin and alveolar volume percent predicted (HPS, 45+/-2 vs NC, 68+/-3, p<0.05; vs HC, 70+/-4, p<0.05), PaO2 (HPS, 70+/-5 mm Hg; HC, 79+/-3 mm Hg, vs NC, 102+/-3 mm Hg, p<0.05) and alveolar-arterial (A-a) O2 gradient (HPS, 42+/-8 mm Hg vs HC, 27+/-2 mm Hg, p<0.05; vs NC, 6+/-2 mm Hg, p<0.05). During CPX, HPS patients achieved a lower peak VO2 percent predicted (HPS, 55+/-6 vs NC, 73+/-3, p<0.05; vs HC, 71+/-5, p<0.05) and VO2 at the ventilatory threshold as percent predicted peak VO2 (HPS, 36+/-2 vs NC, 55+/-4, p<0.05; vs HC 55+/-5, p<0.05). While no differences existed in heart rate and breathing reserve, HPS patients had significantly lower PaO2 (HPS, 50+/-5 mm Hg vs NC, 97+/-4 mm Hg, p<0.05; vs HC, 87+/-6 mm Hg, p<0.05), wider A-a O2 gradient (HPS, 73+/-5 mm Hg vs NC, 13+/-3 mm Hg, p<0.05; vs HC, 31+/-5 mm Hg, p<0.05) and higher VD/VT (HPS, 0.36+/-.03 vs NC, 0.18+/-.02, p<0.05; vs HC, 0.28+/-.02, p<0.05) at peak exercise. For HPS patients, VO2 was negatively correlated with VD/VT (r2=0.9) and positively correlated with PaO2 (r2=0.41) at peak exercise.

CONCLUSIONS

Patients with HPS demonstrate a severe reduction in aerobic capacity, beyond that found in cirrhotics without syndrome. The significant hypoxemia and elevated VD/VT at peak exercise suggest that an abnormal pulmonary circulation contributes to further exercise limitation in patients with HPS.

目的

研究肝肺综合征（HPS）患者对症状限制性运动的反应。

设计

对5例HPS患者进行了最大心肺运动（CPX）反应研究，并与10例对照（正常血氧，NC）肝硬化患者（在年龄、性别、肝病病因和严重程度、吸烟情况及β受体阻滞剂治疗方面相匹配）以及9例无HPS临床证据的低氧血症对照肝硬化患者（HC）进行比较。

设置

三级医疗转诊中心的心肺运动生理实验室。

患者

作为肝移植术前评估一部分而转诊进行CPX的肝硬化患者。

测量

进行标准肺功能测试和超声心动图以评估静息时的肺和心脏功能。在症状限制性最大CPX期间测定峰值耗氧量（VO2）、分钟通气量、动脉血气和死腔（VD/VT）。

结果

HPS患者与NC患者的静息肺量计和肺容积相似，而HC患者存在限制性生理改变。校正血红蛋白后的弥散能力和预测的肺泡容积百分比存在差异（HPS，45±2 vs NC，68±3，p<0.05；vs HC，70±4，p<0.05），动脉血氧分压（PaO2）（HPS，70±5 mmHg；HC，79±3 mmHg，vs NC，102±3 mmHg，p<0.05）以及肺泡-动脉（A-a）氧梯度（HPS，42±8 mmHg vs HC，27±2 mmHg，p<0.05；vs NC，6±2 mmHg，p<0.05）。在CPX期间，HPS患者达到的预测峰值VO2百分比更低（HPS，55±6 vs NC，73±3，p<0.05；vs HC，71±5，p<0.05）以及通气阈值时的VO2占预测峰值VO2的百分比更低（HPS，36±2 vs NC，55±4，p<0.05；vs HC 55±5，p<0.05）。虽然心率和呼吸储备无差异，但HPS患者在运动峰值时的PaO2显著更低（HPS，50±5 mmHg vs NC，97±4 mmHg，p<0.05；vs HC，87±6 mmHg，p<0.05），A-a氧梯度更宽（HPS，73±5 mmHg vs NC，13±3 mmHg，p<0.05；vs HC，31±5 mmHg，p<0.05）以及VD/VT更高（HPS，0.36±.03 vs NC，0.18±.02，p<0.05；vs HC，0.28±.02，p<0.05）。对于HPS患者，运动峰值时VO2与VD/VT呈负相关（r2=0.9），与PaO2呈正相关（r2=0.41）。