title: Does the degree of cyanosis affect myocardial adenosine triphosphate levels and function in children undergoing surgical procedures for congenital heart disease?
abstract: OBJECTIVE
  The outcome of children with cyanosis after cardiac surgical procedures is inferior to that of children who are acyanotic. Animal studies indicated detrimental effects of chronic hypoxia on myocardial metabolism and function. We studied whether the presence or the degree of cyanosis adversely affected myocardial adenosine triphosphate, ventricular function, and clinical outcome in children.
  
  
  METHODS
  Forty-eight children who underwent repair of tetralogy of Fallot were divided according to their preoperative saturation: group I, 90% to 100% (n = 14 patients); group II, 80% to 89% (n = 16 patients); and group III, 65% to 79% (n = 18 patients). Adenosine triphosphate was measured from right ventricular biopsy specimens taken before ischemia, at 15 minutes of ischemia, at end-ischemia, and at 15 minutes of reperfusion. Ejection fraction was measured by echocardiography.
  
  
  RESULTS
  Even before surgical ischemia, compared with groups I and II, group III had lower preoperative ejection fraction (59% +/- 2.9% vs 67% +/- 1.7% and 68% +/- 1.0%; P <.01) and lower preischemic adenosine triphosphate levels (15.1 +/- 2.1 vs 19.1 +/- 1.9 and 21.4 +/- 1.5 micromol/g dry weight; P <.01). After 15 minutes of ischemia, group III had lower adenosine triphosphate levels (11.2 +/- 1.8 vs 14.77 +/- 2.3 and 17. 6 +/- 3.1 micromol/g dry weight; P <.01). With reperfusion, both cyanotic groups lost further adenosine triphosphate compared with partial recovery in the acyanotic group (-22% +/- 3.8%, -20% +/- 3. 1% vs +18% +/- 1.8%; P <.01). Children in group III had a more complicated postoperative course as evidenced by longer ventilatory support (85 +/- 25 hours vs 31 +/- 15 and 40 +/- 21 hours; P =.07), inotropic support (86 +/- 23 hours vs 38 +/- 12 and 36 +/- 4 hours; P <.01), and intensive care unit stay (160 +/- 35 hours vs 60 +/- 10 and 82 +/- 18 hours; P =.02).
  
  
  CONCLUSIONS
  The degree of cyanosis adversely affects myocardial adenosine triphosphate, function, and clinical outcome of children who undergo cardiac operation. Children with cyanosis should be identified as a higher risk group that could be targeted for supportive interventions.
authors.affiliation: Division of Cardiovascular Surgery, Department of Surgery, Hospital for Sick Children, and the Institute of Medical Sciences, University of Toronto, Ontario, Canada.
authors.forename: H K
authors.initials: HK
authors.lastname: Najm
authors.forename: W J
authors.initials: WJ
authors.lastname: Wallen
authors.forename: M P
authors.initials: MP
authors.lastname: Belanger
authors.forename: W G
authors.initials: WG
authors.lastname: Williams
authors.forename: J G
authors.initials: JG
authors.lastname: Coles
authors.forename: G S
authors.initials: GS
authors.lastname: Van Arsdell
authors.forename: M D
authors.initials: MD
authors.lastname: Black
authors.forename: C
authors.initials: C
authors.lastname: Boutin
authors.forename: C
authors.initials: C
authors.lastname: Wittnich
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D003490:Cyanosis / Q000378:metabolism*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D011183:Postoperative Complications / Q000453:epidemiology / Q000378:metabolism*; D011446:Prospective Studies; D012720:Severity of Illness Index; D013771:Tetralogy of Fallot / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000255:Adenosine Triphosphate