Abstract: Objective To investigate the changes of blood gas analysis in patients with chronic liver failure and decompensated cirrhosis. Methods The blood gas analysis in 37 patients with chronic liver failure and decompensated cirrhosis were analyzed. Results Two patients had hypoxia,four patients had orthostatic hypoxia and 11 patients had mild chest tightness. 36 patients had acid-base imbalance in chronic liver failure group,nine had a simple,ten double and two triple acid-base imbalance;in decompensated cirrhosis group,eight had simple and 7 double acid-base imbalance;alkalosis-based type of acid-base imbalance was common in both of the two groups. In chronic liver failure group,the three major types were respiratory alkalosis with metabolic acidosis（38.1%）,respiratory alkalosis（23.8%）,and metabolic alkalosis（14.3%）. In decompensated cirrhosis group,the three major types were respiratory alkalosis（46.7%）,respiratory alkalosis with metabolic alkalosis（26.7%）,and respiratory alkalosis with metabolic acidosis（20.0%）. Conclusion Chronic liver failure and decompensated cirrhosis patients have acid-base imbalance and hypoxemia. Dynamic monitoring of blood gas might have a clinical significance.

Key words: Chronic liver failure, Decompensated cirrhosis, Blood gas analysis, Hypoxemia