title: Effects of acute normovolaemic haemodilution and partial exchange transfusion on blood product utilization, haemostasis and haemodynamics in surgery of the thoracoabdominal aorta. A cohort study in consecutive patients.
abstract: BACKGROUND
  This paper outlines the technique of acute normovolaemic haemodilution with partial exchange transfusion (ANHPET) in surgery of the thoracic and thoracoabdominal aorta. Perioperative coagulation parameters and patterns of blood product utilization observed with this technique are described and compared with results for historical controls treated without ANHPET.
  
  
  METHODS
  During thoracoabdominal aneurysm repair, acute normovolaemic haemodilution with partial exchange transfusion (ANHPET) was used to withdraw of up to 3 L of blood. This was returned to the patient at the end of the reconstruction. Albumin 5% and stored packed red cells (PRC) were used for replacement. Seven patients underwent surgery with ANHPET, and fifteen without. Univariate and multivariate analysis of variance was used to examine differences between these groups.
  
  
  RESULTS
  No differences were observed between the two groups for estimated blood loss, PRC transfused, and postoperative haemoglobin concentration. The ANHPET group received fewer platelets (8 vs 22 units, p = 0.0004), cryoprecipitate (0 vs 13 units, p = 0.02), and desmopressin or epsilon-aminocaproic acid (0 of 7 vs 4 of 15 patients, p = 0.04). FFP use was not significantly different (11 vs 17 units). Postoperatively, PTT values were less prolonged (26 vs 34 sec, p = 0.05) and platelet concentration higher (218 vs 169 x 109/L, p = 0.01) in the ANHPET group. A significant reduction in the total of blood products transfused was observed in the ANHPET group (30 vs 68 units, p = 0.003). Control of hypertension was facilitated by phlebotomy so that nitroglycerine was necessary in low doses only (0.25-1.0 microgram/kg/min).
  
  
  CONCLUSIONS
  ANHPET reduced blood product transfusion, improved postoperative haemostatic parameters and simplified the management of cross-clamping hypertension.
authors.affiliation: Division of Vascular Surgery, Department of Surgery, McMaster University, Hamilton, Canada. cinacs@fhs.mcmaster.ca
authors.forename: C S
authors.initials: CS
authors.lastname: Cinà
authors.forename: C M
authors.initials: CM
authors.lastname: Clase
authors.forename: G
authors.initials: G
authors.lastname: Bruin
mesh_terms: D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000601:surgery*; D015331:Cohort Studies; D005078:Exchange Transfusion, Whole Blood; D005260:Female; D006438:Hemodilution; D006439:Hemodynamics; D006487:Hemostasis; D006801:Humans; D008297:Male; D008875:Middle Aged; D014656:Vascular Surgical Procedures / Q000009:adverse effects / Q000379:methods*