Prolonged mechanical ventilation after CABG: risk factor analysis.

OBJECTIVE

Prolonged ventilation (PV) after coronary artery bypass graft (CABG) surgery is a common postoperative complication. Preoperative and operative parameters were evaluated in order to identify the patients at risk for prolonged ventilation postoperatively in coronary artery bypass graft (CABG) patients.

DESIGN

Retrospective.

SETTING

Research and training hospital, single institution.

PARTICIPANTS

The authors analyzed the prospectively collected data of 830 on- and off-pump coronary bypass patients.

INTERVENTIONS

The relationships of PV (>24 hours) with preoperative and operative parameters were evaluated with logistic regression analysis.

MEASUREMENTS AND MAIN RESULTS

Forty-six patients (5.6%) required PV postoperatively. Hospital mortality was significantly higher in this group (45.7% v 4.0%; p = 0.0001). Univariate analysis showed that these patients were older (65.6±9.3 v 60.4±9.9; p = 0.001), had higher incidences of cerebrovascular disease (21.7% v 10.5%; p = 0.032), advanced ASA (58.7% v 41.8%; p = 0.026) and NYHA classes (32.6% v 12.2%; p = 0.001), and chronic renal dysfunction (20.0% v 4.0%; p = 0.0001). Concomitant procedures were more commonly performed in these patients (30.4% v 7.8%; p = 0.0001), and total durations of perfusion were longer (147.2±69.1 v 95.7±33.9 minutes; p = 0.0001). In regression analysis, advanced NYHA class (odds ratio = 8.2; 95% CI = 1.5-43.5; p = 0.015), chronic renal dysfunction (odds ratio = 7.7; 95% CI = 1.3-47.6; p = 0.027), and longer perfusion durations (p = 0.012) were found to be independently associated with delayed weaning from the ventilator. Every 1-minute increase over 82.5 minutes of cardiopulmonary bypass increased risk of delayed extubation by 3.5% (95% CI = 0.8%-6.4%).

CONCLUSIONS

Postoperative prolonged ventilation is associated with advanced NYHA class, chronic renal dysfunction and longer perfusion times in CABG patients.