[Gasometric alterations in hospitalized cirrhotic patients]

Gas exchange alterations have been described in cirrhotic patients; but by the moment, a few prospective studies have focused in them. The aim of this study was to describe the frequency and severity of gasometric alterations in hospitalized cirrhotic patients, a their correlation with hepatocellular disfunction.

50 consecutive cirrhotic patients (41 males) admitted for liver decompensation (ascites, liver encephalopathy, alcoholic hepatitis and upper gastrointestinal bleeding) without acute or chronic cardiopulmonary disfunction were included in the study. Patients were classified according with Child-Pugh score (A, n = 13; B, n = 21; C, n = 16). Severe alcoholic hepatitis (SAH) was confirmed in 7 patients. Arterial gasometry was performed in all patients before discharge. Contrast echocardiography was performed in any case of suspicion of hepatopulmonary syndrome (HPS).

Light hypoxemia was observed (80.9 mmHg), without differences with Child-Pugh. Hypocapnia was significantly more evident in Child C than in A and B (31.2 +/- 3.1 vs. 38.1 +/- 4.3 y 36.3 +/- 5 mmHg; p < 0,05), respectively. Cirrhotic patients with SAH showed a significantly higher hypocapnia by comparison with others (31.2 +/- 3.1 vs. a 36.3+/-5 mmHg; p < 0.05). In multivariate analysis, independent prognostic variables for hypocapnica were plasmatic levels of protrombin time, albumin and sodium. HPS was confirmed in 8 patients (16%).

The most prevalent gas exchange abnormality in cirrhosis was the alteration of alveolar-arterial oxygen tension gradient, directly correlated with hepatocellur disfunction. Hypocapnia could be a compensatory mechanism or the result of the activation of central respiratory centres by non-depurated substances by the liver.