A composite outcome for neonatal cardiac surgery research

J Thorac Cardiovasc Surg. 2014 Jan;147(1):428-33. doi: 10.1016/j.jtcvs.2013.03.013. Epub 2013 Apr 12.


Objective: The objective of this study was to determine whether a composite outcome, derived of objective signs of inadequate cardiac output, would be associated with other important measures of outcomes and therefore be an appropriate end point for clinical trials in neonatal cardiac surgery.

Methods: Neonates (n = 76) undergoing cardiac operations requiring cardiopulmonary bypass were prospectively enrolled. Patients were defined to have met the composite outcome if they had any of the following events before hospital discharge: death, the use of mechanical circulatory support, cardiac arrest requiring chest compressions, hepatic injury (2 times the upper limit of normal for aspartate aminotransferase or alanine aminotransferase), renal injury (creatinine >1.5 mg/dL), or lactic acidosis (an increasing lactate >5 mmol/L in the postoperative period). Associations between the composite outcome and the duration of mechanical ventilation, intensive care unit stay, hospital stay, and total hospital charges were determined.

Results: The median age at the time of surgery was 7 days, and the median weight was 3.2 kg. The composite outcome was met in 39% of patients (30/76). Patients who met the composite outcome compared with those who did not had a longer duration of mechanical ventilation (4.9 vs 2.9 days, P < .01), intensive care unit stay (8.8 vs 5.7 days, P < .01), hospital stay (23 vs 12 days, P < .01), and increased hospital charges ($258,000 vs $170,000, P < .01). In linear regression analysis, controlling for surgical complexity, these differences remained significant (R(2) = 0.29-0.42, P < .01).

Conclusions: The composite outcome is highly associated with important early operative outcomes and may serve as a useful end point for future clinical research in neonates undergoing cardiac operations.

Trial registration: ClinicalTrials.gov NCT00934843.

Keywords: 20; 21; ALT; AST; CI; CPB; CPR; ECMO; ICU; IQR; RACHS-1; Risk Adjustment for Congenital Heart Surgery 1; alanine aminotransferase; aspartate aminotransferase; cardiopulmonary bypass; cardiopulmonary resuscitation; confidence interval; extracorporeal membrane oxygenation; intensive care unit; interquartile range.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cardiac Output
  • Cardiac Surgical Procedures* / adverse effects
  • Cardiac Surgical Procedures* / economics
  • Cardiac Surgical Procedures* / mortality
  • Cardiopulmonary Bypass
  • Endpoint Determination*
  • Hospital Costs
  • Hospital Mortality
  • Humans
  • Infant, Newborn
  • Intensive Care Units
  • Length of Stay
  • Linear Models
  • Postoperative Complications / economics
  • Postoperative Complications / mortality
  • Postoperative Complications / physiopathology
  • Postoperative Complications / therapy
  • Prospective Studies
  • Research Design*
  • Respiration, Artificial
  • Time Factors
  • Treatment Outcome

Associated data

  • ClinicalTrials.gov/NCT00934843