Saryal S, Celik G, Karabiyikoğlu G
Dept of Chest Diseases, Ankara University Medical School, Turkey.
Monaldi Arch Chest Dis. 1999 Jun;54(3):212-6.
Hypercapnic respiratory failure due to chronic obstructive pulmonary disease (COPD) is an indicator of poor prognosis compared to that for normocapnic patients. On the other hand, there exist particular patients who are hypercapnic during an acute exacerbation of COPD but revert to normocapnia after adequate therapy. The aims of this study were: 1) to document the admission characteristics of such patients in terms of clinical and laboratory findings; and 2) to analyse the long-term course and survival of chronic and reversible hypercapnic and normocapnic patients. Fifty-six consecutive patients, admitted with an acute exacerbation of COPD, were enrolled and divided into three groups according to arterial carbon dioxide tension (Pa,CO2) at first admission: 22 chronic hypercapnic (group 1), 15 reversible hypercapnic (group 2) and 19 normocapnic (group 3) patients. Age, sex, smoking history, white blood cell count, serum sodium, potassium, urea and albumin levels and pulmonary function tests at first admission were similar in the three groups. The haematocrit level was significantly higher in group 1 compared with the other groups. Groups 1 and 2 had lower pH, arterial oxygen tension (Pa,O2) and arterial oxygen saturation (Sa,O2) and a higher Pa,CO2 than group 3. The Pa,CO2 was also higher in group 1 than in group 2. The presence of cor pulmonale was significantly higher in group 1 compared with groups 2 and 3 (81.8 versus 60 and 10.5%, respectively). During the follow-up period, a significant increase was observed in airway obstruction associated with progressive hypercapnia and hypoxaemia in chronic hypercapnic patients, and 12 of 15 (80%) reversible hypercapnic patients progressed to a chronic hypercapnic status. The survival analyses after 10 yrs of follow-up revealed comparable survival durations in chronic and reversible hypercapnic patients (median of 8.86 versus 9.52 yrs, p > 0.05). In conclusion, despite careful monitoring of particular characteristics in chronic and reversible hypercapnic patients at the time of admission, no long-term predictivity of these features for either the course of the disease or survival could be found.
与正常碳酸血症患者相比，慢性阻塞性肺疾病（COPD）所致的高碳酸血症呼吸衰竭是预后不良的一个指标。另一方面，存在一些特殊患者，他们在COPD急性加重期出现高碳酸血症，但经过充分治疗后恢复为正常碳酸血症。本研究的目的是：1）根据临床和实验室检查结果记录此类患者的入院特征；2）分析慢性和可逆性高碳酸血症及正常碳酸血症患者的长期病程和生存率。连续纳入56例因COPD急性加重入院的患者，并根据首次入院时的动脉二氧化碳分压（Pa,CO2）分为三组：22例慢性高碳酸血症患者（第1组）、15例可逆性高碳酸血症患者（第2组）和19例正常碳酸血症患者（第3组）。三组患者的年龄、性别、吸烟史、白细胞计数、血清钠、钾、尿素和白蛋白水平以及首次入院时的肺功能检查结果相似。第1组患者红细胞压积水平显著高于其他两组。第1组和第2组的pH值、动脉血氧分压（Pa,O2）和动脉血氧饱和度（Sa,O2）较低，Pa,CO2高于第3组。第1组的Pa,CO2也高于第2组。与第2组和第3组相比，第1组肺心病的发生率显著更高（分别为81.8%、60%和10.5%）。在随访期间，慢性高碳酸血症患者出现与进行性高碳酸血症和低氧血症相关的气道阻塞显著增加，15例可逆性高碳酸血症患者中有12例（80%）进展为慢性高碳酸血症状态。随访10年后的生存分析显示，慢性和可逆性高碳酸血症患者的生存时间相当（中位数分别为8.86年和9.52年，p>0.05）。总之，尽管在入院时仔细监测慢性和可逆性高碳酸血症患者的特定特征，但未发现这些特征对疾病病程或生存有长期预测性。
