Predictors of early extubation (within 4 hours) in adult cardiac surgical patients

Background

The extubation time after cardiac surgery and its impact on outcome have been extensively studied recently. Many studies reported that early extubation (within 8 hours) appears to be safe without an increased incidence of morbidity. Some intraoperative and preoperative factors may have an important influence in predicting early extubation and determining strategies to optimize postoperative therapy.

Objective

To investigate predictors of early extubation.

Design

A prospective cohort study.

Setting

A 19-bed medico-surgical ICU in a private hospital.

Patients

All 104 patients admitted after cardiac surgery.

Measurements and results

One hundred and four cardiac surgical patients were admitted to our ICU from March to November 2005; 63 (60.6%) were male; 85 (81.7%) were submitted to coronary artery bypass grafts, 17 (16.3%) to valvular replacement and 23 (2%) to combined surgery. The mean extubation time was 8.9 ± 21.96 hours. Patients were divided into two groups: early extubation (EE – within 4 hours) (n = 56 [53.8%]) and late extubation (LE – after 4 hours) (n = 48 [46.2%]). Mean extubation times for EE and LE were 2.52 ± 1.49 hours and 16.52 ± 30.7 hours (P < 0.001), respectively. Multivariate logistic regression analysis showed that the use of peridural anesthesia was the best independent predictor of early extubation (OR = 9.37, 95% CI 2.19–40.17). The presence of acute coronary syndrome and the Ontario score were also independent predictors of early extubation (OR 7.17 with 95% CI 1.99–25.77 and OR 0.648 with 95% CI 0.5–0.84, respectively). The Ontario score had an area under the receiver operating curve of 0.731 (95% CI 0.635–0.826), with the best cutoff value of ≤5 points.

Conclusions

In this cohort, use of peridural anesthesia was the best predictor of early extubation after cardiac surgery. The presence of acute coronary syndrome and a low Ontario score also were independent predictors of successful early extubation. This conclusion raises the hypothesis that patients with an elevated Ontario score could benefit from peridural anesthesia to be extubated earlier.