title: Reduction of hemodilution in small adults undergoing open heart surgery: a prospective, randomized trial.
abstract: BACKGROUND
  Given that there is an association between the degree of hemodilution during cardiopulmonary bypass (CPB) and postoperative complications, patients-outcome might be improved if the nadir hematocrit concentration is kept within an optimal range. Smaller patients are more likely to have a low hematocrit during CPB: this phenomenon may be related, at least partially, to the extreme hemodilution induced by a large fixed CPB priming volume.
  
  
  METHODS
  Forty patients with a body surface area (BSA) < 1.7 m2 undergoing open heart operations were randomized to either standard CPB with full prime volume (control group) or reduced prime extracorporeal circuit and vacuum-assisted venous drainage (VAVD) (study group).
  
  
  RESULTS
  There were no significant differences between the groups with respect to baseline characteristics, body surface area, hematologic profile and operative data. Clinical outcomes were similar. Nadir hematocrit and hemoglobin on bypass were significantly lower in the control group (22 +/- 2.3 vs. 24 +/- 2.5%, p < 0.02 and 7.4 +/- 0.7 vs. 8 +/- 0.9 g/dl, p < 0.04, respectively). Postoperative chest tube drainage was significantly higher in the control group (272 +/- 253 vs. 139 +/- 84 ml, p < 0.04). There was no difference in blood transfusion in the two groups (0.5 +/- 1.14 vs. 1.0 +/- 1.77 units of packed red blood cells (PRBC), p = 0.29).
  
  
  CONCLUSIONS
  Lowering CPB priming volume by means of using a small oxygenator and vacuum-assisted venous drainage (VAVD) resulted in a significant decrease of intraoperative hemodilution. This technique should be strongly considered for patients with a small BSA (<1.7 m2) undergoing open heart surgery.
authors.affiliation: Department of Cardiovascular Anesthesia and Intensive Care, San Raffaele Hospital, Via Olgettina 60, 20132 Milan, Italy. pappalardo.federico@hsr.it
authors.forename: F
authors.initials: F
authors.lastname: Pappalardo
authors.forename: C
authors.initials: C
authors.lastname: Corno
authors.forename: A
authors.initials: A
authors.lastname: Franco
authors.forename: G
authors.initials: G
authors.lastname: Giardina
authors.forename: A M
authors.initials: AM
authors.lastname: Scandroglio
authors.forename: G
authors.initials: G
authors.lastname: Landoni
authors.forename: G
authors.initials: G
authors.lastname: Crescenzi
authors.forename: A
authors.initials: A
authors.lastname: Zangrillo
mesh_terms: D000368:Aged; D001803:Blood Transfusion; D049628:Body Size; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000379:methods*; D001026:Coronary Artery Bypass; D005260:Female; D006438:Hemodilution / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000517:prevention & control; D011446:Prospective Studies; D016896:Treatment Outcome