Cardiovascular response to acute normovolemic hemodilution in patients with coronary artery diseases: Assessment with transesophageal echocardiography.
In this prospective case-control study, Licker et al. studied the cardiac response to moderate acute normovolemic hemodilution (target hematocrit value 28%) in anesthetized beta-blocked coronary artery disease patients with normal to moderate left ventricular function. Hemodilution was associated with a moderate increase in cardiac ouptut resulting from both an increase in stroke volume and a […]
Effects of standardized acute normovolemic hemodilution on intraoperative allogeneic blood transfusion in patients undergoing major maxillofacial surgery.
This study demonstrated the practicality and safety of acute normovolemic hemodilution used to reduce allogeneic red blood cell transfusion in patients undergoing major maxillofacial surgery. In the absence of a control group, the real efficacy of this blood conservation technique is difficult to evaluate. – Philippe Van der Linden
Preoperative acute normovolemic hemodilution: a meta-analysis.
This meta-analysis reviewed 42 trials evaluating the efficacy and safety of preoperative acute normovolemic hemodilution (ANH). The authors reported that the risk of allogeneic transfusion was similar among patients receiving ANH and those receiving another blood conservation technique or usual care. Patients receiving ANH, however, had less total bleeding than patients receiving usual care and […]
Hyperoxic ventilation reduces 6-hour mortality at the critical hemoglobin concentration.
This experimental study convincingly demonstrates that hyperoxic ventilation of pigs diluted to the individual critical hematocrit is able to guarantee oxygenation of the vital organs and thereby allows survival. One can conclude from this study that general and tissue hypoxia encountered at the transfusion trigger can safely and rapidly be reversed by switching to hyperoxic […]
Normovolemic hemodilution with Hb vesicle solution attenuates hypoxia in ischemic hamster flap tissue.
Encapsulation of human hemoglobin in liposome vesicles represents a useful method to attenuate the vasoactivity observed with conjugated or polymerized hemoglobin solutions currently under experimental and clinical investigation. Another advantage of hemoglobin vesicles is that oxygen affinity of the solution can be adapted by modifying the amount of coencapsulated pyridoxal 5′-phosphate, an allosteric effector. In […]
Improved oxygenation in ischemic hamster flap tissue is correlated with increasing hemodilution with Hb vesicles and their O2 affinity.
Encapsulation of human hemoglobin in liposome vesicles represents a useful method to attenuate the vasoactivity observed with conjugated or polymerized hemoglobin solutions currently under experimental and clinical investigation. Another advantage of hemoglobin vesicles is that oxygen affinity of the solution can be adapted by modifying the amount of coencapsulated pyridoxal 5′-phosphate, an allosteric effector. In […]
The hemodynamic and metabolic effects of shivering during acute normovolemic hemodilution.
In this rather sophisticated experimental study, the authors observed that severe acute normovolemic hemodilution (target hemoglobin concentration of 5.2 g/dL) significantly reduced the ability of the anesthetized animals to sustain a major increase in tissue oxygen demand resulting from shivering. They also provided further evidence that in these conditions of increased oxygen demand, the heart […]
Tolerance to acute isovolemic hemodilution: effect of anesthetic depth.
This is a very important contribution to the field of acute normovolemic hemodilution (ANH), because it clearly indicates the need of adjusting the depth of anesthesia in dependence upon the initial and the target hematocrit of the patient undergoing intentional hemodilution. The article is a must for each clinician using ANH in practice. – Konrad […]
New mathematical model for the correct prediction of the exchangeable blood volume during acute normovolemic hemodilution.
In this rather complex article, the authors describe a new mathematical model that can be used to predict the exchangeable blood volume during acute normovolemic hemodilution. This model was validated on both experimental and clinical protocols. It predicts the exchangeable blood volume more reliably than the commonly used Bourke and Smith formula, no matter if […]
Heart rate increases linearly in response to acute isovolemic anemia.
From data collected in different earlier studies, the authors confirm their hypothesis that, in unmedicated healthy humans, heart rate increases linearly in response to acute isovolemic hemodilution. The authors also determine that the slope of the relationship between heart rate and hemoglobin is slightly greater for females than it is for males. – Philippe Van […]
The influence of crystalloid and colloid replacement solutions in acute normovolemic hemodilution: a preliminary survey of hemostatic markers.
This prospective randomized single blinded study nicely showed the dual effects of plasma substitutes used in acute normovolemic hemodilution. Solutions that have an impact on hemostasis like dextran and high molecular weight starches may attenuate the hypercoagulability phase usually observed in the immediate postoperative period, but their use can be associated with increased perioperative bleeding. […]
Effectiveness of acute normovolemic hemodilution to minimize allogeneic blood transfusion in major liver resections.
In this randomized controlled trial, acute normovolemic hemodilution (ANH) resulted in a decrease of allogeneic blood exposure in ASA I-II patients undergoing major liver resection. As emphasized by Dr. Weiskopf in the accompanying editorial, this study was designed to meet the different criteria required to adequately assess the efficacy of ANH. In addition, the results […]
