title: Low-weight infants are at increased mortality risk after palliative or corrective cardiac surgery.
abstract: BACKGROUND
  Low weight is an established risk factor for mortality after congenital cardiac surgery. Given the advances in the care of neonates and infants after surgery, we sought to examine the effect of low weight on outcomes in the current era.
  
  
  METHODS
  From 2002 to 2012, 2051 infants aged 90 days or less underwent cardiac surgery including 534 (26.0%) with single-ventricle pathology. Regression models examined the effect of low weight (≤ 2.5 kg; n = 274, 13.4%) on early and late outcomes.
  
  
  RESULTS
  Overall, the incidence of prematurity, associated chromosomal/extracardiac abnormalities was higher in infants who weighed 2.5 kg or less than in those who weighed more than 2.5 kg; the incidence of single-ventricle pathology was comparable between the 2 groups. In addition, infants who weighed 2.5 kg or less underwent more palliation and had a higher proportion of STAT (Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery) risk category 4 and 5 procedures. Adjusted regression models showed that low weight (≤ 2.5 kg) did not increase unplanned reoperation (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.48-1.67; P = .73) or extracorporeal membrane oxygenation requirement (OR, 1.23; 95% CI, 0.68-2.22; P = .49), however it was associated with significant increase in hospital mortality (OR, 2.15; 95% CI, 1.33-3.50; P = .002). In addition, there was a significant association between low weight and increased duration of postoperative mechanical ventilation and intensive care unit and hospital stays. Adjusted hazard analysis showed that weight equal to or less than 2.5 kg was associated with diminished late survival (hazard ratio, 1.89; 95% CI, 1.39-2.55; P < .001) and that was evident in all patients subgroups (P < .001 for all).
  
  
  CONCLUSIONS
  In a large single-center series, low weight continues to be associated with increased early mortality risk and resource utilization after palliative and corrective cardiac surgery. The hazard of death in low-weight patients continues beyond the perioperative period for at least 1 year before normalizing. Strategies to improve outcomes for this high-risk population must address perioperative care, outpatient surveillance, and management.
authors.affiliation: Division of Cardiothoracic Surgery, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga. Electronic address: balsoufi@hotmail.com.
authors.forename: Bahaaldin
authors.initials: B
authors.lastname: Alsoufi
authors.affiliation: Labatt Family Heart Center, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Cedric
authors.initials: C
authors.lastname: Manlhiot
authors.affiliation: Sibley Heart Center, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga.
authors.forename: William T
authors.initials: WT
authors.lastname: Mahle
authors.affiliation: Division of Cardiothoracic Surgery, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga.
authors.forename: Brian
authors.initials: B
authors.lastname: Kogon
authors.affiliation: Sibley Heart Center, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga.
authors.forename: William L
authors.initials: WL
authors.lastname: Border
authors.affiliation: Sibley Heart Center, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga.
authors.forename: Angel
authors.initials: A
authors.lastname: Cuadrado
authors.affiliation: Sibley Heart Center, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga.
authors.forename: Robert
authors.initials: R
authors.lastname: Vincent
authors.affiliation: Labatt Family Heart Center, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Brian W
authors.initials: BW
authors.lastname: McCrindle
authors.affiliation: Division of Cardiothoracic Surgery, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Ga.
authors.forename: Kirk
authors.initials: K
authors.lastname: Kanter
mesh_terms: D001724:Birth Weight; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000401:mortality*; D016009:Chi-Square Distribution; D005260:Female; D005845:Georgia; D005865:Gestational Age; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D017052:Hospital Mortality; D006801:Humans; D007223:Infant; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D010166:Palliative Care; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome