title: Patients at risk for low systemic oxygen delivery after the Norwood procedure.
abstract: BACKGROUND
  Identification of patients at risk for inadequate systemic oxygen delivery following the Norwood procedure could allow for application of more intensive monitoring, provide for earlier intervention of decreased cardiac output, and result in improved outcome.
  
  
  RESULTS
  Superior vena cava saturation (SvO2) and arteriovenous oxygen content difference were prospectively monitored as indicators of systemic oxygen delivery and recorded hourly for the first 48 hours in 29 of 33 consecutive patients following the Norwood procedure. Risk factors were evaluated using multiple linear regression to determine their impact on SvO2 and arteriovenous oxygen content difference. Age less than 8 days, weight less than 2.5 kg, aortic atresia, and prolonged cardiopulmonary bypass time were risk factors for low SvO2 and wide arteriovenous oxygen content difference (p < 0.05). Phenoxybenzamine and increasing time after operation were associated with higher SvO2 and narrower arteriovenous oxygen content difference (p < 0.05). Thirty-day survival was 97% and hospital survival was 94%. The earliest death occurred on postoperative day 20. Survival to bidirectional cavopulmonary shunt was 77%. Preoperative mechanical ventilation was the only risk factor identified for late death.
  
  
  CONCLUSIONS
  Aortic atresia, low weight, younger age, and prolonged cardiopulmonary bypass, previously identified risk factors for mortality, were associated with decreased SvO2 and narrower arteriovenous oxygen content difference in the early postoperative period. The impact of this hemodynamic vulnerability on mortality was minimized by continuous SvO2 monitoring.
authors.affiliation: Department of Surgery (Cardiothoracic Surgery), Children's Hospital of Wisconsin, Medical College of Wisconsin, Milwaukee 53226, USA. jstwedde@mcw.edu
authors.forename: J S
authors.initials: JS
authors.lastname: Tweddell
authors.forename: G M
authors.initials: GM
authors.lastname: Hoffman
authors.forename: R T
authors.initials: RT
authors.lastname: Fedderly
authors.forename: N S
authors.initials: NS
authors.lastname: Ghanayem
authors.forename: J M
authors.initials: JM
authors.lastname: Kampine
authors.forename: S
authors.initials: S
authors.lastname: Berger
authors.forename: K A
authors.initials: KA
authors.lastname: Mussatto
authors.forename: S B
authors.initials: SB
authors.lastname: Litwin
mesh_terms: D002303:Cardiac Output, Low / Q000209:etiology* / Q000401:mortality; D005260:Female; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000401:mortality / Q000601:surgery*; D000860:Hypoxia / Q000209:etiology* / Q000401:mortality; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010100:Oxygen / Q000097:blood; D010166:Palliative Care; D011183:Postoperative Complications / Q000209:etiology* / Q000401:mortality; D011446:Prospective Studies; D012307:Risk Factors; D015996:Survival Rate
chemical_list: D010100:Oxygen