Acid-base balance disorders are associated with increased 1-month and 3-month mortality in patients with acute heart failure

Abstract

Background/Introduction: Arterial blood gas (ABG) analysis is one of the main tests for decision-making in patients with severe dyspnea. However, the significance of ABG analysis on the prognosis for the acute heart failure (AHF) patients remains unclear. Purpose: The study evaluated whether acid-base balance disorders at the time of admission are associated with 1- and 3-month rehospitalisation and mortality rates of AHF patients. Methods: A prospective observational cohort study enrolled consecutive patients with acute dyspnea from March, 2015 till August, 2016. The exclusion criterion was a suspected acute coronary syndrome. Data of 144 study patients with adjudicated diagnosis of AHF, available ABG and biochemical blood analyses at admission and completed 3-months follow up were included in the analysis. Outcomes were eval- uated with Kaplan-Meier curves and Cox proportional hazard model to estimate survival rates, hazard ratios (HR) and 95% confidence intervals (CI). Data were anal- ysed using SPSS v23 statistical package. Results: 71 (49.3%) patients were male and 73 (50.7%) female. Acid-base balance disorders were found in 90 (62.5%) patients: 25 (17.3%) patients had acidosis (15 [10.4%] metabolic, 10 [6.9%] respiratory), 58 patients (40.3%) had alkalosis (7 [4.9%] metabolic, 51 [35.4%] respiratory), 7 (4.9%) patients had a mixed A-B disorder. Both respiratory and metabolic acidosis (HR=4.65, 95% CI: 1.42; 15.25, P=0.011) and mixed A-B disorders (HR=4.66, 95% CI: 1.05; 21.58, P=0.049) at admission were significantly associated with 1-month mortality (total number of deaths – 8). Metabolic acidosis (HR=7.63, 95% CI: 2.46; 23.67, P < 0.001) and mixed A-B dis- orders (HR=5.52, 95% CI: 1.55; 19.57, P=0.008) also displayed a significant effect on 3-month mortality (total 12 deaths). On-admission A-B disorders had no impact on 1- and 3-month rehospitalisation rates. The cumulative 90-day survival was 85% for patients with A-B disorders and 93% [...]