Acute normovolemic hemodilution in spinal fusion surgery

Background: Spinal fusion surgeries are accompanied by significant blood loss. Acute normovolemic hemodilution is one of the autologous blood transfusion techniques that is proved to improve tissue perfusion through decreasing blood viscosity. However, its effect on hemodynamics, hematologic state, and coagulation profile is controversial. Aim of the work: To detect safety of ANH as an alternative to allogenic blood transfusion in major surgeries. Patients and methods: Forty adult patients undergoing spinal fusion surgery were randomly assigned into two groups: hemodilution group (group H: n = 20) and control group (group C: n = 20). Samples were collected five times. T1: just after the induction of anesthesia and before hemodilution starts. T2: just after the end of hemodilution or 40 min after the induction of anesthesia in the control group. T3: at the start of surgical closure. T4: before the reversal from residual neuromuscular effect. T5: 3 h postoperative. Samples included: Arterial blood gases (ABGs), Hb level, Ht%, serum Na+ and K+ levels, platelet count (Plt), bleeding time (BT), activated partial thromboplastin time (aPTT), and international neutralizing ratio (INR). Results: Heart rate, arterial blood pressure and CVP showed no significant differences during intra- and postoperative times between the two groups. Reduction in Hb and Ht % occurred in both groups compared to basal and was more significantly reduced in group H compared to group C at T2. Platelets were reduced in both groups compared to basal and significantly reduced in group H at T2 compared to group C. BT, aPTT, and INR were not affected all through the study time in both groups. Serum Na+, Serum K+, and ABGs showed insignificant differences all through the study time. Conclusions: Acute normovolemic hemodilution can be considered as a safe and effective alternative for allogenic blood transfusion (avoiding all its hazards) in spinal fusion surgery. (C) 2011 Egyptian Society of Anesthesiologists. Production and hosting by Elsevier B.V.