1.
The effect of acute normovolaemic haemodilution on the inflammatory response and clinical outcome in abdominal aortic aneurysm repair--results of a pilot trial
Wolowczyk L, Nevin M, Day A, Smith FC, Baird RN, Lamont PM
European Journal of Vascular and Endovascular Surgery. 2005;30((1):):12-9.
Abstract
OBJECTIVES To determine the effect of acute normovolaemic haemodilution (ANH) on the inflammatory response and clinical outcome in elective open abdominal aortic aneurysm (AAA) repair. DESIGN Randomised controlled clinical trial. METHODS Thirty-six patients were randomised to undergo ANH or act as controls. Cell salvage was permitted in both groups. Heterologous blood was transfused according to pre-determined triggers. Outcome measures were markers of the systemic inflammatory response in serum and urine observed at multiple time points, and clinical recovery. RESULTS Median 890 (range 670-1620) ml of blood was removed at ANH in 16 patients. There were no differences in peri-operative changes in neutrophil count ( P = 0. 13), serum C-reactive protein ( P = 0. 38), interleukin-6 ( P = 0. 50), total antioxidant capacity ( P = 0. 73), urinary secretion of albumin ( P = 0. 97) or retinol binding protein ( P = 0. 41). There were no differences in the mortality and morbidity rates, systemic inflammatory response syndrome, ITU or hospital stay. CONCLUSIONS ANH, when used in combination with cell salvage, made no impact on systemic inflammatory response and clinical outcome when compared to cell salvage alone after AAA repair. ANH cannot be recommended for routine use in patients undergoing abdominal aortic aneurysm surgery when cell salvage is available.
2.
Haemodilutional effect of standard fluid management limits the effectiveness of acute normovolaemic haemodilution in AAA surgery--results of a pilot trial
Wolowczyk L, Nevin M, Smith FC, Baird RN, Lamont PM
European Journal of Vascular and Endovascular Surgery. 2003;26((4):):405-11.
Abstract
OBJECTIVE To evaluate the impact of standard fluid management on the effectiveness of ANH as a blood conservation method in elective open AAA repair. DESIGN Prospective randomised controlled study. METHODS Thirty-four patients undergoing elective AAA repair were randomised to have ANH (16) or act as controls (18). Intra-operative cell salvage was permitted in both groups. Haemoglobin (Hb) concentrations were determined at variable intervals peri-operatively. Blood loss and the use of heterologous blood were recorded. RESULTS The pre- and post-operative Hb concentrations, surgical blood loss and the use of cell salvage were similar in both groups. Hb concentration (median, range) decreased significantly from pre-operative to aortic clamping (with blood loss <100 ml) in ANH patients from 8. 8 (7. 5-10. 2) to 5. 7 (4. 2-6. 6)mmol/l following ANH but also in controls from 8. 6 (7. 5-9. 7) to 7. 0 (4. 5-9. 0)mmol/l due to fluid infusion (P<0. 01 for every comparison). Bank blood requirements were similar: median 2 units in ANH and 2. 5 units in control patients (P=0. 68). CONCLUSIONS Large volumes of fluids infused during AAA repair already conserve blood by the mechanism of hypervolaemic haemodilution. When cell salvage is used with standard fluid management during AAA repair, additional ANH is ineffective in saving blood.