Abstract 15379: Prognostic Impact of Arterial Carbon Dioxide Levels in Patients With Acute Decompensated Heart Failure
Background: Although assessing arterial blood gas (ABG) is recommended, prognostic values of arterial carbon dioxide (CO2) levels in patients with acute decompensated heart failure (ADHF) are not well-established. Thus, we investigated the relationship between partial pressure of arterial carbon dioxide (PaCO2) levels and long-term mortality in patients with ADHF.
Methods: A cohort of 2300 patients consecutively admitted to the cardiac intensive-care unit from 2007 to 2011 were studied. Among them, patients admitted due to ADHF (defined according to the current guideline) are enrolled. Patients with other life-threatening condition such as neoplasm and shock were excluded. Baseline data were collected at the time of patients’ arrival to the hospital. All eligible patients were categorized according to the tertiles of PaCO2 on admission. The risk of PaCO2 levels for all-cause mortality was assessed by multivariable Cox proportional hazards regression analysis with backward elimination.
Results: Finally, 435 patients were assessed. At a median follow-up of 1.8 years, there were 115 deaths (26.4%). Cumulative survivals were significantly different across the groups (Figure). In the multivariable model including other independent baseline variables (age, sex, body mass index, ischemic heart disease, atrial fibrillation, heart rate, BNP level, hemoglobin, C-reactive protein, sodium and potassium levels, compared with patients in the middle tertile (PaCO2 ranged from 31.7 to 36.8 Torr), patients in the lower tertile (PaCO2 <31.7 Torr) showed a greater risk of mortality (hazard ratio [HR], 2.18; P=0.025) whereas those in the higher tertile (PaCO2 ≥36.8 Torr) showed no significantly greater risk of mortality (HR, 1.22; P=0.587).
Conclusion: In patients admitted with ADHF, lower PaCO2 level on admission was associated with long-term mortality.
- © 2013 by American Heart Association, Inc.