METHODS: A retrospective cohort study.
METHODS: Single-institutional, university hospital.
METHODS: All patients admitted to the ICU after CABG between January 2009 and December 2012.
METHODS: None.
RESULTS: Based on PaCO2 status during the first 24 hours after CABG, 1,011 patients were classified into 4 groups: normocapnia, hypocapnia, hypercapnia, and dual hyper/hypocapnia. The 30-day mortality rate was 0.7% (n = 4) for normocapnia, 1.5% (n = 4) for hypocapnia, 2.2% (n = 3) for hypercapnia, and 7.5% (n = 4) for the dual-exposure group. The extubation times were 13.3±21.7 hours, 15.8±21.37 hours, 21.79±39.70 hours, and 42.29±75.35 hours, respectively. After adjusting for confounding variables, the dual hypocapnia and hypercapnia exposure group was associated with increased 30-day mortality (odds ratio [OR] = 8.08; 95% confidence interval [CI], 1.82-35.86; p = 0.006) and delayed extubation (OR = 2.40; 95% CI, 1.24-4.64; p = 0.010).
CONCLUSIONS: Exposure to both hypocapnia and hypercapnia within 24 hours after CABG was associated independently with increased risk of 30-day mortality and delayed extubation. Exposure to either hypocapnia or hypercapnia alone was not associated with patient outcome.