Neonates are at high risk of bleeding after open-heart surgery. We sought to determine pre-operative and intra-operative risk factors for increased bleeding after neonatal open-heart surgery with cardiopulmonary bypass.

We conducted a retrospective cohort study of neonates (0–30 days old) who underwent open-heart surgery with cardiopulmonary bypass from January, 2009, to March, 2013. Cardiac diagnosis; demographic and surgical data; and blood products, haemostatic agents, and anti-thrombotic agents administered before, during, and within 24 hours after surgery were abstracted from the electronic health record and anaesthesia records. The outcome of interest was chest tube output (in ml/kg body weight) within 24 hours. Relationships between chest tube output and putative associated factors were evaluated by unadjusted and adjusted linear regression.

The cohort consisted of 107 neonates, of whom 79% had a Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) Mortality Category of 4 or 5. Median chest tube output was 37 ml/kg (range 9–655 ml/kg). Age, African-American race, and longer durations of surgery and cardiopulmonary bypass each had statistically significant associations with increased chest tube output in unadjusted analyses. In multivariable analysis, African-American race retained an independent, statistically significant association with increased chest tube output; the geometric mean of chest tube output among African-American neonates was 71% higher than that of Caucasians (95% confidence interval, 29–125%; p = 0.001).

Among neonates with CHD undergoing open-heart surgery with cardiopulmonary bypass, African-American race is independently associated with greater chest tube output over the first 24 hours post-operatively.