Predictive risk factors for delayed extubation in patients undergoing coronary artery bypass grafting

Abstract

Prolonged mechanical ventilation increases hospitalization costs, airway and lung trauma, and stress. The objective of this study was to elucidate patient characteristics and operative variables that predict delayed extubation in patients undergoing coronary artery bypass grafting (CABG). The records of 167 patients who underwent CABG between 1994 and 1998 were examined retrospectively. The patients were divided into early and delayed extubation groups. Putative factors affecting the duration of intubation were included in a univariate analysis using the t-test and chi-squared test. A logistic regression model was then developed to determine the factors associated with delayed extubation. Forty-four percent of the patients needed prolonged mechanical ventilation (more than 24h). Univariate predictors of delayed extubation (P < 0.05) were emergency surgery, preoperative use of an intra-aortic balloon pump (IABP), the duration of anesthesia, surgery, cardiopulmonary bypass and aortic cross-clamping, the total volume of fentanyl. lowest rectal temperature, glucose level, perioperative transfusion, bleeding, perioperative heart failure, perioperative insertion of IABP, postoperative transfusion, cardiac index, inspired oxygen fraction (FiO2), arterial oxygen tension (PaO2), the PaO2/FiO2 ratio, and the volume of catecholamine. In the delayed extubation group, the intensive care unit stay was significantly longer (P < 0.001) and re-exploration was required more frequently (P = 0.004). Excellent prediction was provided by a model consisting of six variables: age, duration of surgery, perioperative heart failure, glucose level, postoperative transfusion, and the PaO2/FiO2 ratio. These results suggest that decreasing the cardiopulmonary bypass time, maintaining a low glucose level during cardiopulmonary bypass, and ensuring adequate perioperative hemostasis may help to avoid pulmonary dysfunction and delayed extubation. Moreover, the PaO2/FiO2 ratio may be a useful predictor of delayed extubation in patients undergoing CABG.

Cardiopulmonary Predicators of Dysfunctional Ventilator Weaning Response after Coronary Artery Bypass Graft

“…It results from many complications of DVWR such as acute respiratory distress syndrome, 10% to 15% (20,21); multiorgan dysfunction syndrome, 15% to 19% (20,21); deep vein thrombosis, 10% to 12% (29)(30)(31); and ventilator-associated pneumonia, 30% to 50% (32,33). Other health care problems resulting from DVWR are increased ICU length of stay and cost (8,15,34,35). Early detection of DVWR is imperative to prevent postoperative complications and premature weaning after CABG surgery.…”

“…Other researchers have focused on identifying the associated factors and complications of early extubation failure (2,(40)(41)(42)(43)(44)(45). Although many researchers have attempted to identify the predictive factors for early extubation failure and prolonged mechanical ventilation (PMV), which is the outcome of DVWR, no single proven predictor is reported to be valid to predict DVWR (34,37,46,47).…”

“…In past decades, research studies have focused on examining various weaning protocols and found that a fast track weaning protocol can be effectively and safely implemented among postoperative CABG patients (8,15,34,35). Despite implementing fast track weaning protocols, there is a gap in the practice of weaning postoperative cardiac surgery patients, which is evidenced by the findings from many studies (26,51).…”

“…Other health care problems resulting from DVWR are increased ICU length of stay and ICU cost (8,15,34,35). Providing critical care consumes 30% of the hospital expenses for just 8% of the hospital population (14).…”

“…Providing critical care consumes 30% of the hospital expenses for just 8% of the hospital population (14). Several researchers who focused on studying ICU length of stay and early extubation after cardiac surgery reported that increased ICU length of stay and ICU cost is directly associated with DVWR and PMV (8,15,34,35). Prolonged mechanical ventilation > 48 hours accounted for 42.8% of the total ICU cost (14).…”