Arterial Oxygenation Is an Independent Risk Factor of Mortality in Patients With Liver Cirrhosis: Presented at AASLD

By Cheryl Lathrop

BOSTON -- November 3, 2010 -- Low arterial partial pressure of oxygen (PaO2) is an independent risk factor of mortality in patients with liver cirrhosis, researchers said here on November 1 at the 61st Annual Meeting of the American Association for the Study of Liver Diseases (AASLD).

Initiation of long-term oxygen therapy (LTOT) improves PaO2, and possibly survival, according to Valentin Fuhrmann, MD, Department of Internal Medicine III, Gastroenterology and Hepatology, Medical University of Vienna, Vienna, Austria, and colleagues.

Respiratory insufficiency and pulmonary complications are a frequent finding in patients with liver cirrhosis and impaired arterial oxygenation is a common consequence. Although the European Respiratory Society task force on pulmonary hepatic vascular disorders recommends initiation of LTOT in patients with PaO2 <=60 mm Hg, there is a lack of clinical data supporting this recommendation.

In light of this, the researchers decided to investigate the prevalence and prognostic impact of arterial oxygenation on 1-year transplant-free survival in patients with cirrhosis without hepatocellular carcinoma (HCC).

A total of 540 patients with liver cirrhosis (without HCC) listed for liver transplantation at the Medical University Vienna were included in the study. All patients had arterial blood gas analysis. One-year transplant-free survival was stratified according to PaO2.

The median age of patients was 53 years and 65% were male. The causes of their cirrhosis were as follows: 51% alcohol, 22% viral hepatitis, and 23% other causes. The 1-year transplant-free survival was 74%. And the mean PaO2 was 81 +- 12 mm Hg.

The researchers observed a nonlinear association between PaO2 and mortality. Patients with PaO2 <=60 mm Hg had significantly increased mortality rates compared with patients with PaO2 >60 mm Hg.

The crude mortality ratio in patients with PaO2 <=60 mm Hg was 4.24. After adjustment for Model for End-Stage Liver Disease, age, sex, and sodium, the rate ratio for mortality in patients with PaO2 <=60 mm Hg was 2.74 (P <.01).

Since PaO2 <=60 mm Hg is an independent risk factor of mortality in patients with liver cirrhosis, initiation of LTOT seems to improve PaO2 and possibly survival. "Initiation of long-term oxygen therapy seems to be rational in these patients," said Dr. Fuhrmann.

[Presentation title: Prognostic Impact of Arterial Oxygenation in Liver Cirrhosis. Abstract 1163]

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