Hypoalbuminemia and Length of Mechanical Ventilation in ARDS

Abstract

PURPOSE: Acute respiratory distress syndrome (ARDS) is a potentially fatal disease process. The main mechanism of morbidity and mortality is hypoxia and multi-organ failure. There is need for markers that may help earlier diagnosis and predict clinical outcomes. Low albumin causes decreased oncotic pressure in pulmonary circulation leading to more extravasation of fluid into alveoli. There have been few studies showing higher risk of developing ARDS in hypo-proteinemia. The purpose of this study is to determine if there is an association of hypoalbuminemia with length of mechanical ventilation in ARDS. METHODS: We conducted a retrospective cohort study of subjects admitted to our institution between Jan. 1, 2006 to Mar. 15, 2011, inclusive. Patients with ARDS were divided into two groups: Group 1 had mechanical ventilation (VT) ≥ 96 hrs; Group 2 had VT< 96 hrs. We examined serum albumin concentrations on admission and compared them between the groups. RESULTS: There were 341 patients who met criteria for inclusion in our cohort. Of these, 153 had VT ≥ 96 hrs (Group 1) and 188 had VT < 96 hrs (Group 2). Median (IQR) serum albumin for Group 1 was 2.3 (1.7 to 2.9) g/dl vs. 2.5 (2.0 to 3.0) g/dl (p = 0.011). Cut-off that distinguished Group 1 and 2 was 1.9 g/dl. At this level, OR (95%CI) was 1.98 (1.17 to 3.34); p = 0.012. There was no significant difference in mortality between the groups: 24% in Group 1 and 30% in Group 2 (p = 0.27). CONCLUSIONS: Our study indicates that there is a significant association between low albumin level and longer length of mechanical ventilation in patients with ARDS. This study suggests that low albumin level should be taken a as a poor prognostic indicator in ARDS. Whether correcting or preventing hypoalbuminemia will decrease ventilator dependent days and eventually improve survival still needs further investigation with larger randomized studies. CLINICAL