Improving patients' readiness for coronary artery bypass graft surgery.

BACKGROUND: Preoperative interventions improve outcomes for patients after coronary artery bypass surgery (CABG). OBJECTIVE: To reduce mortality for patients undergoing urgent CABG. METHODS: Eight centers implemented preoperative aspirin and statin, preinduction heart rate less than 80/min, hematocrit greater than 30%, blood sugar less than 150 mg/dL (8.3 mmol/L), and delayed surgery at least 3 days after a myocardial infarction. Data were collected on the last 150 isolated, urgent CABGs at each center (n=1200). A "bundle" score of 0 to 100 was calculated for each patient to represent the percentage of interventions used. RESULTS: Scores ranged from 33 to 100. About 56% of patients had a perfect score. Crude mortality and composite rates were lower in patients with higher scores, but once adjusted for patient and disease characteristics, the difference in scores was not significant. Higher scores were associated with shorter intubation: 6.0 hours (score 100), 8.0 hours (score 80-99), 8.4 hours (score<80) (log-rank P<.001). Median length of stay was shorter for patients with higher scores: 5 days (score 100), 6 days (scores 80-99), and 6 days (scores <80) (log-rank P<.001). CONCLUSION: Implementation of interventions to optimize patients' "readiness for surgery" is associated with shorter intubation times and shorter hospital stays after CABG.

Impact of perioperative acute kidney injury as a severity index for thirty-day readmission after cardiac surgery.

BACKGROUND: Of patients undergoing cardiac surgery in the United States, 15% to 20% are re-hospitalized within 30 days. Current models to predict readmission have not evaluated the association between severity of postoperative acute kidney injury (AKI) and 30-day readmissions. METHODS: We collected data from 2,209 consecutive patients who underwent either coronary artery bypass or valve surgery at 7 member hospitals of the Northern New England Cardiovascular Disease Study Group Cardiac Surgery Registry between July 2008 and December 2010. Administrative data at each hospital were searched to identify all patients readmitted to the index hospital within 30 days of discharge. We defined AKI stages by the AKI Network definition of 0.3 or 50% increase (stage 1), twofold increase (stage 2), and a threefold or 0.5 increase if the baseline serum creatinine was at least 4.0 (mg/dL) or new dialysis (stage 3). We evaluate the association between stages of AKI and 30-day readmission using multivariate logistic regression. RESULTS: There were 260 patients readmitted within 30 days (12.1%). The median time to readmission was 9 (interquartile range, 4 to 16) days. Patients not developing AKI after cardiac surgery had a 30-day readmission rate of 9.3% compared with patients developing AKI stage 1 (16.1%), AKI stage 2 (21.8%), and AKI stage 3 (28.6%, p < 0.001). Adjusted odds ratios for AKI stage 1 (1.81; 1.35, 2.44), stage 2 (2.39; 1.38, 4.14), and stage 3 (3.47; 1.85 to 6.50). Models to predict readmission were significantly improved with the addition of AKI stage (c-statistic 0.65, p = 0.001) and net reclassification rate of 14.6% (95% confidence interval: 5.05% to 24.14%, p = 0.003). CONCLUSIONS: In addition to more traditional patient characteristics, the severity of postoperative AKI should be used when assessing a patient's risk for readmission.

Preoperative white blood cell count and risk of 30-day readmission after cardiac surgery.

Approximately 1 in 5 patients undergoing cardiac surgery are readmitted within 30 days of discharge. Among the primary causes of readmission are infection and disease states susceptible to the inflammatory cascade, such as diabetes, chronic obstructive pulmonary disease, and gastrointestinal complications. Currently, it is not known if a patient's baseline inflammatory state measured by crude white blood cell (WBC) counts could predict 30-day readmission. We collected data from 2,176 consecutive patients who underwent cardiac surgery at seven hospitals. Patient readmission data was abstracted from each hospital. The independent association with preoperative WBC count was determined using logistic regression. There were 259 patients readmitted within 30 days, with a median time of readmission of 9 days (IQR 4-16). Patients with elevated WBC count at baseline (10,000-12,000 and >12,000 mm(3)) had higher 30-day readmission than those with lower levels of WBC count prior to surgery (15% and 18% compared to 10%-12%, P = 0.037). Adjusted odds ratios were 1.42 (0.86, 2.34) for WBC counts 10,000-12,000 and 1.81 (1.03, 3.17) for WBC count > 12,000. We conclude that WBC count measured prior to cardiac surgery as a measure of the patient's inflammatory state could aid clinicians and continuity of care management teams in identifying patients at heightened risk of 30-day readmission after discharge from cardiac surgery.