title: Hemolysis in extracorporeal circulation: relationship between time and procedures.
abstract: BACKGROUND
  Extracorporeal circulation (EC) is very important in cardiac surgery but causes significant damage to the blood, including hemolysis.
  
  
  OBJECTIVE
  To quantify the rate of hemolysis at different times during EC in elective coronary artery bypass grafting.
  
  
  METHODS
  We measured rates of hemolysis of 22 patients at 6 different times during myocardial revascularization during EC: T0 - before the start of EC, T1 - five minutes after of the EC initiation, T2 - 30 minutes of EC, T3 - immediately before the aortic unclamping, T4 - immediately before passage of the residual volume to the patient and T5 - five minutes after the passage of the residual volume to the patient. Rates of hemolysis were calculated between the intervals of time: T0-T1; T1-T2; T2-T3; T3-T4 and T4-T5.
  
  
  RESULTS
  The first 5 minutes after the EC showed the highest rate of hemolysis (P = 0.0003) compared to the others calculated rates, representing 29% of the total haemolysis until T4 (Immediately before passage of the residual volume to the patient).
  
  
  CONCLUSIONS
  There were no significant changes in the rate of hemolysis during the suction in the aortic root (P> 0.38), nor with the procedure used for the passage of the residual volume of blood in the circuit to the patient.
authors.affiliation: State University of Campinas, Instituto Federal de São Paulo, Brazil. fubaldo@terra.com.br
authors.forename: Francisco Ubaldo
authors.initials: FU
authors.lastname: Vieira Junior
authors.forename: Nilson
authors.initials: N
authors.lastname: Antunes
authors.forename: Reinaldo Wilson
authors.initials: RW
authors.lastname: Vieira
authors.forename: Lúcia Madalena Paulo
authors.initials: LM
authors.lastname: Alvares
authors.forename: Eduardo Tavares
authors.initials: ET
authors.lastname: Costa
mesh_terms: D000704:Analysis of Variance; D001800:Blood Specimen Collection / Q000379:methods / Q000706:statistics & numerical data; D001026:Coronary Artery Bypass / Q000379:methods*; D005112:Extracorporeal Circulation / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006461:Hemolysis / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D013997:Time Factors