Risk factors associated with readmission after pediatric cardiothoracic surgery

Approximately 10% to 20% of children are readmitted congenital heart surgery. Readmissions are now being viewed by payers as preventable complications of the original surgery or hospitalization, and there have been proposals by insurance agencies to deny coverage of the additional expenses incurred by the readmission. With hopes to reduce the potential impact, we analyzed patients undergoing congenital heart surgery at our institution in order to identify risk factors for readmission.

We performed a retrospective cohort study of 685 patients who underwent congenital heart surgery at Children's Healthcare of Atlanta between January 1, 2009 and December 31, 2009, and were subsequently discharged. Readmission was defined as an admission within 30 days discharge. Demographic, preoperative, operative, and postoperative variables were evaluated. Univariate comparisons were made between the readmission and non-readmission groups, and multivariate Poisson regression analysis was performed to identify potential risk factors for readmission.

There were 74 readmissions in 70 patients. Reasons for readmission included effusive, pleural or pericardial (19, 26%), gastrointestinal (18, 24%), respiratory (4, 5%), infectious (14, 19%), cardiac (11, 15%), and other (8, 11%) complications. In comparisons between readmitted and non-readmitted patients, significant demographic variables included younger age, lower weight, and Hispanic ethnicity in the readmitted group. Significant preoperative variables included genetic anomaly, failure to thrive, and mechanical ventilation. Significant operative variables included risk-adjusted congenital heart surgery score, and significant postoperative variables included nasogastric feeds at discharge, palliated cardiac physiology, longer intensive care unit stay, and longer hospital stay. In multivariate analysis, Hispanic ethnicity (relative risk [RR] 1.86; 95% confidence interval [CI] 1.10 to 3.12; p=0.019], preoperative failure to thrive (RR 2.88; 95% CI 1.53 to 5.40; p=0.001), and length of stay greater than 10 days (RR 4.24; 95% CI 2.26 to 7.96; p<0.001) were significant risk factors for readmission.

Potential risk factors for readmission after congenital heart surgery have been identified. Hopefully, altering the discharge process and the early postoperative care in these high-risk patients can minimize the impact of hospital readmissions after congenital heart surgery.