Use Of Acute Normovolemic Hemodilution Research Articles

Acute normovolemic hemodilution reduced the frequency and amount of perioperative allogeneic blood transfusion in pediatric and adolescent scoliosis surgery: a retrospective observational study.

The aim of the present study is to investigate whether acute normovolemic hemodilution (ANH) can reduce the frequency and amount of perioperative allogeneic blood transfusion (ABT) (intraoperative ABT and postoperative ABT until discharge from the hospital) in pediatric and adolescent scoliosis surgery. This single-center, retrospective, observational study included the perioperative data of 147 patients who were 18years old or younger and underwent scoliosis surgery. Patients were divided into groups according to whether they received ANH: i.e., an ANH group and control group. Propensity-score-adjusted multivariable logistic regression analysis was performed to determine whether ANH can reduce the frequency of perioperative ABT. A total of 125 patients were analyzed, 95 and 30 in the ANH and control group, respectively. The intraoperative/postoperative ABT frequency was significantly lower in the ANH group than in the control group (17.9% vs. 36.7%, p = 0.044). The amount of ABT [median (IQR): 0 (0, 0) mL/kg vs. 0 (0, 16.3) mL/kg, p = 0.033] was also significantly lower in the ANH group than in the control group. Propensity-score-adjusted multivariable logistic regression analysis indicated that ANH use [odds ratio: 0.15; 95% confidence interval: 0.03, 0.77; p = 0.023)] was associated with a lower risk of ABT after adjusting for intraoperative blood loss and duration of surgery. ANH use can reduce the frequency and amount of perioperative ABT in pediatric and adolescent scoliosis surgery.

Pro: Acute Normovolemic Hemodilution Should Be Used in Infective Endocarditis Patients Coming for Primary or Redo Cardiac Surgery

ACUTE NORMOVOLEMIC HEMODILUTION (ANH) is a blood conservation strategy well-known to reduce allogeneic blood transfusion. More specifically, perioperative autologous whole blood collection and reinfusion during cardiac surgery have been shown to reduce allogeneic red blood cell (RBC) transfusions (4% v 44% in a control group). 1 Henderson RA Judd M Strauss ER et al. Hematologic evaluation of intraoperative autologous blood collection and allogeneic transfusion in cardiac surgery. Transfusion. 2021; 61: 788-798 Crossref PubMed Scopus (8) Google Scholar In addition, the use of ANH has the potential to improve coagulation parameters, thereby reducing the administration of clotting factors and other blood products. 1 Henderson RA Judd M Strauss ER et al. Hematologic evaluation of intraoperative autologous blood collection and allogeneic transfusion in cardiac surgery. Transfusion. 2021; 61: 788-798 Crossref PubMed Scopus (8) Google Scholar , 2 Barile L Fominskiy E Di Tomasso N et al. Acute normovolemic hemodilution reduces allogeneic red blood cell transfusion in cardiac surgery: A systematic review and meta-analysis of randomized trials. Anesth Analg. 2017; 124: 743-752 Crossref PubMed Scopus (93) Google Scholar , 3 Henderson RA Mazzeffi MA Strauss ER et al. Impact of intraoperative high-volume autologous blood collection on allogeneic transfusion during and after cardiac surgery: A propensity score matched analysis. Transfusion. 2019; 59: 2023-2029 PubMed Google Scholar This has been attributed to the shielding effect of ANH on platelets and clotting factors from activation, consumption, and shearing stress injury from the cardiopulmonary bypass (CPB) circuit. ANH also improves tissue perfusion by hemodilution, enhances body's tolerance to blood loss, and likely reduces surgical blood loss. 4 Zhou J. A review of the application of autologous blood transfusion. Braz J Med Biol Res. 2016; 49: e5493 Crossref PubMed Scopus (26) Google Scholar Other potential benefits of ANH are bone marrow stimulation and the endogenous regeneration of hematopoietic cells, leading to faster recovery from anemia after surgery.

Decreased transfusion requirements with use of acute normovolemic hemodilution in open aortic aneurysm repair

ObjectiveAcute normovolemic hemodilution (ANH) is an operative blood conservation technique involving the removal and storage of patient blood after the induction of anesthesia, with maintenance of normovolemia by crystalloid and/or colloid replacement. Developed and used predominately in cardiac surgery, ANH has been applied to the vascular surgery population. However, data regarding the effects on transfusion requirements in this population are limited. The objective of the present study was to compare the transfusion requirements and coagulopathy for patients who had undergone open abdominal aortic aneurysm repair (oAAAR) using ANH to those for patients who had received only product replacements, as clinically indicated. MethodsWe performed a retrospective review of patients who had undergone elective oAAAR at a quaternary aortic referral center from 2017 to 2019. Those eligible for ANH, with no active cardiac ischemia, no valvular disease, normal left ventricular and right ventricular function, chronic kidney disease stage <3, hematocrit >38%, and a normal coagulation profile were included in the present study. Patient demographics and characteristics and operative variables, including aneurysm extent, clamp site, visceral and renal ischemia time, operative time, and transfusion requirements, were collected. Postoperative morbidity, mortality, and length of stay were analyzed. The patients with and without ANH were matched and compared. Continuous measures were analyzed using Wilcoxon rank sum tests and t tests. ResultsDuring the study period, 209 oAAARs had been performed. Of the 209 patients, 76 had met the inclusion criteria. Of these 76 patients, 27 had undergone ANH and 49 had not. The patients with ANH had required fewer PRBC transfusions intraoperatively (median, 0 U; interquartile range [IQR], 0-1 U; median, 1 U; IQR, 0-2 U; P = .02), at 24 hours (median, 0 U; IQR, 0-1 U; vs median, 1 U; IQR, 0-2 U; P = .008), at 48 hours (median, 0 U; IQR, 0-1 U; vs median, 1 U; IQR, 0-2; P = .007), and throughout the admission (median, 0 U; IQR, 0-1 U; vs median, 2 U; IQR, 0-2 U; P = .011). No difference was found in the number of intraoperative platelet or cryoprecipitate transfusions. At 48 hours, the ANH group had had significantly greater platelet counts (142 ± 35.8 × 103/μL vs 124 ± 37.6 × 103/μL; P = .044), lower partial thromboplastin time, and lower international normalized ratio. No difference in myocardial infarction, return to the operating room, or mortality (one death overall). The ANH patients had a shorter length of stay (7.0 ± 2.7 vs 8.8 ± 4.8 days; P = .041). ConclusionsThe use of ANH during oAAAR resulted in fewer intraoperative and postoperative PRBC transfusions with improved coagulation parameters and a shorter hospital length of stay.

Transfusion-free strategies in liver and pancreatic surgery

Presenter: Sujit Kulkarni MD | University of Southern California Background: Major liver and pancreatic resections often require peri-operative transfusions. This limits surgical options for patients who do not accept major blood fractions and elevates morbidity risks for those who do accept allogeneic blood products. Methods: A 23-year, single center, retrospective review of Jehovah’s Witness (JW) patients undergoing liver and pancreatic resections was performed, and patient outcomes were measured. A model that reconciles potential blood losses with blood conservation by acute normo-volemic hemodilution (ANH) is described. Results: Seventy-six JW patients underwent major resections (47 livers, 29 pancreas). ANH was utilized in 50 patients (liver 31, pancreas 19) with removal of ANH (median 2 units) that were returned once hemostasis was assured. There were no perioperative mortalities. Clavien-Dindo Grade ≥ 3 morbidity occurred in patients with liver resection (8.5%), pancreato-duodenectomy (16.6%), and distal pancreatic resections (9%). A quantitative mathematical formula was developed to provide guidance for optimizing the use of ANH to maintain hemodynamic stability and prevent the need for blood transfusion. Conclusion: Intra-operative whole blood removal with ANH preserves red cell mass, platelets, and coagulation factors for timely reinfusion making transfusion-free major hepato-biliary-pancreatic resections feasible. Application of the described strategy will help reduce costs, infection rates, and minimize transfusion in mainstream populations.

The Use of Acute Normovolemic Hemodilution in Clipping Surgery for Aneurysmal Subarachnoid Hemorrhage

The occurrence of coronavirus disease 2019 (COVID-19) has overwhelmed the blood supply chain worldwide and severely influenced clinical procedures with potential massive blood loss, such as clipping surgery for aneurysmal subarachnoid hemorrhage (aSAH). Whether acute normovolemic hemodilution (ANH) is safe and effective in aneurysm clipping remains largely unknown. Patients with aSAH who underwent clipping surgery within 72 hours from bleeding were included. The patients in the ANH group received 400 mL autologous blood collection, and the blood was returned as needed during surgery. The relationships between ANH and perioperative allogeneic blood transfusion, postoperative outcome, and complications were analyzed. Sixty-two patients with aSAH were included between December 2019 and June 2020 (20 in the ANH group and 42 in the non-ANH group). ANH did not reduce the need of perioperative blood transfusion (3 [15%] vs. 5 [11.9%]; P= 0.734). However, ANH significantly increased serum hemoglobin levels on postoperative day 1 (11.5 ± 2.5 g/dL vs. 10.3 ± 2.0 g/dL; P= 0.045) and day 3 (12.1 ± 2.0 g/dL vs. 10.7 ± 1.3 g/dL; P= 0.002). Multivariable analysis indicated that serum hemoglobin level on postoperative day 1 (odds ratio, 0.895; 95% confidence interval, 0.822-0.973; P= 0.010) was an independent risk factor for unfavorable outcome, and receiver operating characteristic curve analysis showed that it had a comparable predictive power to World Federation of Neurosurgical Societies grade (Z= 0.275; P > 0.05). ANH significantly increased postoperative hemoglobin levels, and it may hold the potential to improve patients' outcomes. Routine use of ANH should be considered in aneurysm clipping surgery.

Standards and Best Practice for Acute Normovolemic Hemodilution: Evidence-based Consensus Recommendations

To develop a standardized approach to the implementation and performance of acute normovolemic hemodilution (ANH) in order to reduce the incidence of bleeding and allogeneic blood transfusion in high-risk surgical bleeding-related cardiac surgery with cardiopulmonary bypass (CPB). A 2-round modified RAND-Delphi consensus process. Seven physicians from multiple geographic locations and clinical disciplines including anesthesiology and cardiac surgery and 1 cardiac surgery perfusionist participated in the survey. One registered nurse, specializing in Patient Blood Management, participated in the discussion but did not participate in the survey. A modified RAND-Delphi method was utilized that integrated evidence review with a face-to-face expert multidisciplinary panel meeting, followed by repeated scoring using a 9-point Likert scale. Consensus was determined as a result from the second round survey, as follows: median rating of 1-3: ANH acceptable; median rating of 7-9: ANH not acceptable; median rating of 4-6: use clinical judgment. Evidentiary review identified 18 key peer-reviewed manuscripts for discussion. Through the consensus-building process, 39 statements including 26 contraindications to ANH and 10 CPB patient variables were assessed. In total, 22 statements were accepted or modified for the second scoring round. Consensus was reached on 6 conditions in which ANH would or would not be acceptable, showing that development of a standardized approach for the use of ANH in high-risk surgical bleeding and allogeneic blood transfusion is clearly possible. The recommendations developed by this expert panel may help guide the management and inclusion of ANH as an evidence and consensus-based blood conservation modality.

Acute normovolemic hemodilution reduced allogeneic blood transfusion without increasing perioperative complications in patients undergoing free-flap reconstruction of the head and neck.

PurposeThe present case–control study was conducted to evaluate whether acute normovolemic hemodilution (ANH) can reduce the need for perioperative allogeneic blood transfusion (ABT) and affect the incidence of perioperative complications in free-flap reconstruction of the head and neck.MethodsThis single-center, retrospective, observational study included the perioperative data of 123 patients who underwent free-flap reconstruction of the head and neck following oncological surgery. Patients were divided into the following two groups according to whether they received ANH: ANH group and non-ANH group. We investigated whether ANH can reduce the need for perioperative ABT using propensity score-adjusted logistic regression analysis.ResultsOf the 123 patients, 113 patients were assessed; 57 patients were in the ANH group and 56 patients were in the non-ANH group. The rate [ANH group vs. non-ANH group, n (%): 2 (3.5%) vs. 23 (41.1%), p < 0.0001] and amount [median (IQR): 0 mL (0, 0) vs. 0 mL (0, 280), p < 0.0001] of ABT were significantly lower in the ANH group than in the non-ANH group. Propensity score-adjusted multivariate logistic regression analysis indicated that ANH use [odds ratio (OR): 0.040; 95% confidence interval (CI) 0.005, 0.320; p = 0.0024)] was one of the independent predictors of perioperative ABT. There were no significant differences in the incidences of post-operative complications between the two groups.ConclusionANH use can reduce the need for perioperative ABT in patients undergoing free-flap reconstruction of the head and neck without increasing the incidence of post-operative complications.

The Novel Use of a Low Prime Modified Ultrafiltration Apparatus in a 13-kg Jehovah’s Witness Patient: A Case Report

Modified ultrafiltration (MUF) is used in neonates and infants to reduce volume overload and increase oxygen-carrying capacity post cardiopulmonary bypass (CPB). In addition, it decreases edema, attenuates complementation activation and immunogenic response to CPB. Hemodilution in the pediatric patient has always been a challenge, countered in part by miniaturization of CPB circuits. We describe a case in which we maintained an acceptable hematocrit level greater than 24%, considered the nadir below which the adverse effects of hemodilution can become evident. We performed this by the novel use of an intravenous warming device (enFlow, Vyaire Medical, Mettawa, IL) to reduce the prime volume of our MUF circuit by more than 50%. We present the case and discuss the advantages and disadvantages of using a low-prime MUF circuit. We were able to conduct “bloodless” CPB, with the use of acute normovolemic hemodilution, miniaturization of the CPB and MUF circuits.

The use of acute normovolemic hemodilution in paediatric cardiac surgery.

Acute normovolemic hemodilution (ANH) is considered safe and effective in decreasing perioperative transfusion in paediatric populations undergoing high blood-loss surgeries. We determined the association between ANH and the intraoperative use of allogeneic blood products in paediatric cardiac surgery patients. This is a single-centre retrospective cohort study including paediatric patients between 0 and 36months of age undergoing surgical repair or palliation of their cardiac defect with the use of cardiopulmonary bypass between November 2013 and November 2014. Our primary endpoint was the volume per kilogram of body weight of any blood product administered. Secondary endpoints were postoperative bleeding, coagulation profile, creatinine, vasoactive support, duration of mechanical ventilation, and hospital stay. In all, 50 patients met eligibility criteria and were included. Of those, seven were exposed to ANH and while 43 patients were treated according to usual care. Baseline characteristics were similar in both groups. After adjustment for baseline characteristics including age, American Society of Anaesthesiologists (ASA) classification, and Risk Adjusted Congenital Heart Surgery score, ANH was associated with reduced administration of allogenic blood products, with the mean difference between groups of 57.5ml/kg (95% CI: 34.8, 80.2). The ANH group had lower blood losses at 6 and 24h postoperatively. There were no differences in the duration of ICU or hospital stay. We found a reduction in the administration of blood products and lower postoperative blood losses associated with the use of ANH in paediatric cardiac surgery patients. The data suggest that ANH might be beneficial in reducing perioperative morbidity in this patient population.

The Effect of Autologus Blood Priming on Cerebral Oximetry in Congenital Cardiac Surgery Patients

Hemodilution is one of the sequelae of cardiopulmonary bypass (CPB). Autologous blood priming (retrograde autologous priming [RAP]/venous antegrade priming [VAP]) and acute normovolemic hemodilution (ANH) may be effective techniques to minimize hemodilution. The primary objective of this study is to investigate the impact of RAP/VAP combined with ANH on changes in cerebral saturations. A retrospective analysis of 52 patients undergoing congenital cardiac surgery requiring CPB between July 2014 and March 2015 was performed. Bivariate analysis correlated RAP/VAP and ANH volumes. SrO2 change scores were regressed on all covariates using multivariable least-squares models. The average percent of circulating blood volume (CBV) removed during RAP/VAP was 21 ± 10% in the cyanotic group and 15 ± 5% in the acyanotic group (p =.006). There was a decrease in SrO2 from 70 ± 11% at baseline to 55 ± 13% at CPB initiation, although this decrease did not differ by cyanosis (p = .668) or use of ANH (p = .566). Bivariate correlation and multivariable regression analysis of the SrO2 change score further demonstrated no statistically significant correlation between percent of CBV removed during RAP/VAP or ANH and the magnitude of the decline in SrO2. RAP and VAP help minimize hemodilution at the onset of CPB. This study further supports the use of these techniques in a pediatric population by demonstrating declines in SrO2 during RAP/VAP were consistent among cyanotic and acyanotic, including those who underwent ANH.

The effectiveness of acute normolvolemic hemodilution and autologous prime on intraoperative blood management during cardiac surgery.

Intraoperative blood management during cardiac surgery is a multifaceted process incorporating various interventions directed at optimizing oxygen delivery and enhancing hemostasis. The purpose of this study was to evaluate the effects of acute normovolemic hemodilution (ANH) and autologous priming (AP) on preserving the hematocrit during cardiopulmonary bypass (CPB). Case records from a national registry of adult patients who underwent cardiac surgery between January and October 2016 were reviewed. Groups were determined as follows: ANH, AP, ANH+AP or Neither. Primary endpoint was first the hematocrit on CPB with secondary endpoints of hematocrit drift and red blood cell (RBC) transfusion rate. Eighteen thousand and twenty-four (18,024) consecutive patients were reviewed. The first CPB hematocrit was lowest in the ANH group (26.5%±4.4%) and highest in ANH+AP patients (27.5%±4.8%) (p<0.001). The change in hematocrit was greatest in the ANH group (8.3%±3.9%) compared to both the AP (6.4%±3.8%) and ANH+AP (6.9%±4.1%) groups (p<0.001). Intraoperative RBC transfusions were as follows: ANH 26 (7.8%), AP 2,531 (20.0%), ANH+AP 287 (10.3%) and Neither 592 (26.7%) (p<0.001). Regression results show that the use of ANH will result in the greatest decline in hematocrit values. When combined with AP, higher hematocrits and lower transfusions were seen.

Blood Conservation—A Team Sport

Cardiac surgery accounts for between 15% and 20% of all blood product utilization in the United States. A body of literature suggests that patients who are exposed to even small quantities of blood have an increased risk of morbidity and mortality, even after adjusting for pre-operative risk. Despite this body of literature supporting a restrictive blood management strategy, wide variability in transfusion rates exist across institutions. Recent blood management guidelines have shed light on a number of potentially promising blood management strategies, including acute normovolemic hemodilution (ANH) and retrograde autologous priming (RAP). We evaluated the literature concerning ANH and RAP, and the use of both techniques among centers participating in the Perfusion Measures and outcomes (PERForm) registry. We leveraged data concerning ANH and RAP among 10,203 patients undergoing isolated coronary artery bypass grafting (CABG) procedures from 2010 to 2014 at 27 medical centers. Meta-analyses have focused on the topic of ANH, with few studies focusing specifically on cardiac surgery. Two meta-analyses have been conducted to date on RAP, with many reporting higher intra-operative hematocrits and reduced transfusions. The rate of red blood cell transfusions in the setting of CABG surgery is 34.2%, although varied across institutions from 16.8% to 57.6%. Overall use of ANH was 11.6%, although the utilization varied from .0% to 75.7% across institutions. RAP use was 71.4%, although varied from .0% to 99.0% across institutions. A number of blood conservation strategies have been proposed, with varying levels of evidence from meta-analyses. This uncertainty has likely contributed to center-level differences in the utilization of these practices as evidenced by our multi-institutional database. Perfusion databases, including the PERForm registry, serve as a vehicle for perfusionist's to track their practice, and contribute to multidisciplinary team efforts aimed at assessing and improving the value of cardiac surgical care.

Selecting Patients for Acute Normovolemic Hemodilution during Hepatic Resection: A Prospective Randomized Evaluation of Nomogram-Based Allocation

Acute normovolemic hemodilution (ANH) decreases transfusion rates but adds to the complexity of anesthetic management during hepatectomy. A randomized controlled trial was conducted to determine if selecting patients for ANH using a transfusion nomogram improves management and resource use compared with selection using extent of resection. One hundred fourteen patients undergoing partial hepatectomy were randomized to a clinical arm (ANH used for resection of ≥ 3 liver segments) or a nomogram arm (ANH used for predicted probability of transfusion ≥ 50% based on a previously validated nomogram). The primary end point was appropriate management, defined as avoidance of ANH in patients at low risk or use of ANH in patients at high risk for allogeneic red blood cell transfusions. Between September 2009 and May 2011, 58 patients were randomized to the clinical arm and 56 to the nomogram arm. Demographics, diagnoses, extent of resection, blood loss, and incidence and grade of complications did not differ between the 2 groups. There were no differences in perioperative transfusions or laboratory values. Nomogram-based allocation did not change appropriate management overall (80% vs 76% in the clinical arm; p = 0.65), but did result in comparable perioperative outcomes and a trend toward decreased ANH use (30% vs 47%; p = 0.09), particularly in low blood loss (estimated blood loss ≤ 400 mL) cases (12% vs 25%; p = 0.04). Although allocation of intraoperative management using a transfusion nomogram did not improve appropriate management overall, it more effectively identified low blood loss cases and reduced ANH use in patients least likely to benefit.

Incidence and Risk Factors of Intraoperative Adverse Events During Donor Lobectomy for Living-Donor Liver Transplantation: A Retrospective Analysis

Objective: To evaluate the frequency, type, and predictors of intraoperative adverse events during donor hepatectomy for Living-Donor Liver Transplantation (LDLT). Material and methods: Retrospective analysis of 182 consecutive LDLT donors' data between May 2002 and September 2008. Results: Ninety one patients (50%) had at least 1 intraoperative adverse event including hypothermia (39%), hypotension (26%), need for transfusions (17%), and hypertension (7%). Patients who had an adverse event were older (p=0.001), had a larger graft weight (p=0.023), more frequently underwent right hepatectomy (p=0.019), and more-frequently were classified as American Society of Anesthesiologists physical status class II (p=0.027) than those who did not have these adverse events. Logistic regression analysis revealed that only age (95% confidence interval 1.018-1.099, p=0.001) was a risk factor for intraoperative adverse events. Patients with these adverse events more frequently required intensive care unit admission and were hospitalized longer postoperatively. A before-after analysis showed that after introduction of in-line fluid warmers and more frequent use of acute normovolemic hemodilution the frequency of intraoperative adverse events were significantly lower (80% vs 29%, p< 0.001). Conclusions: Intraoperative adverse events such as hypothermia and hypotension were common in LDLT donors, and older age was associated with an increased risk of these adverse events. However, the impact of these adverse events on postoperative recovery is not clear. (Approval from the Institutional Review Board and Ethics Committee of Baskent University)

Incidence and Risk Factors of Intraoperative Adverse Events During Donor Lobectomy for Living-Donor Liver Transplantation: A Retrospective Analysis

To evaluate the frequency, type, and predictors of intraoperative adverse events during donor hepatectomy for living-donor liver transplant. Retrospective analyses of the data from 182 consecutive living-donor liver transplant donors between May 2002 and September 2008. Ninety-one patients (50%) had at least 1 intraoperative adverse event including hypothermia (39%), hypotension (26%), need for transfusions (17%), and hypertension (7%). Patients with an adverse event were older (P = .001), had a larger graft weight (P = .023), more frequently underwent a right hepatectomy (P = .019), and were more frequently classified as American Society of Anesthesiologists physical status class II (P = .027) than those who did not have these adverse events. Logistic regression analysis revealed that only age (95% confidence interval 1.018-1.099; P = .001) was a risk factor for intraoperative adverse events. Patients with these adverse events more frequently required admission to the intensive care unit and were hospitalized longer postoperatively. A before and after analysis showed that after introduction of in-line fluid warmers and more frequent use of acute normovolemic hemodilution, the frequency of intraoperative adverse events was significantly lower (80% vs 29%; P < .001). Intraoperative adverse events such as hypothermia and hypotension were common in living-donor liver transplant donors, and older age was associated with an increased risk of these adverse events. However, the effect of these adverse events on postoperative recovery is not clear.

Impact of Acute Normovolemic Hemodilution with Autoplasma Transfusion on Hemostatic Parameters during Abdominal Delivery

Objective: to evaluate the impact of acute normovolemic hemodilution (ANH) with autoplasma transfusion on hemostatic parameters during cesarean section. Subjects and methods. The study covered 119 patients in whom ANH was used during cesarean section. Group 1 included 62 women undergoing ANH with autoplasma transfusion; Group 2 (control) comprised 57 pregnant women receiving ANH only. Examination of the hemostatic system involved studies of the plasma link, thromboelastogram readings, vascular platelet hemostasis and evaluation of intravascular thrombogenesis. Results. Transfusion of stored autoplasma as a hemostatic component during ANH favored the development of moderate hypercoagulation due to a significant increase in fibrinogen concentrations by 8%, r+k shortening by 11%, and a rise in the thrombodynamic potential index by 12%. A statistically significant difference has been found in the results between the groups at a stage of surgical hemostasis, which proves the best hemostat-ic effect of ANH used with autoplasma transfusion. Conclusion. The study has demonstrated that the combined use of ANH and autoplasma transfusion contributes to the stabilization of the blood coagulation potential during cesarean section and extends the feasibilities of ANH when the volume of intraoperative blood loss is as high as 25% of the circulating blood volume. Key words: cesarean section, acute normovolemic hemodilution, autoplasma transfusion, coagulation potential.

A Prospective Randomized Trial of Acute Normovolemic Hemodilution Compared to Standard Intraoperative Management in Patients Undergoing Major Hepatic Resection

Hepatic resection is the most effective treatment for many malignant and benign conditions affecting the liver and biliary tree. Despite improvements, major partial hepatectomy can be associated with considerable blood loss and transfusion requirements. Transfusion of allogeneic blood products, although potentially life-saving, is associated with many potential complications. The primary aim of this study was to determine if acute normovolemic hemodilution (ANH), an established blood conservation technique, reduces the requirement for allogeneic red cell transfusions in patients undergoing major hepatic resection. One hundred thirty patients undergoing major hepatic resection (> or =3 segments) were prospectively randomized to undergo either ANH or standard anesthetic management (STD). In the ANH group, intraoperative blood collection was performed to a target hemoglobin of 8.0 g/dL. Low central venous pressure anesthetic technique was used intraoperatively for both groups. A standardized transfusion protocol was applied to all patients intraoperatively and throughout the hospital stay. From April 2004 to March 2007, 63 patients were randomized to ANH and 67 to STD. Demographics, diagnoses, liver function, extent of resection, intraoperative blood loss, operative time, incidence and grade of complications, and length of hospital stay were similar between the 2 groups. ANH reduced the overall allogeneic red cell transfusion rate by 50% compared with STD [12.7% (n = 8) vs. 25.4% (n = 17), respectively; P = 0.067. ANH patients were less often transfused intraoperatively (n = 1, 1.6%) compared with the STD group (n = 7, 10.4%) (P = 0.036), had higher postoperative hemoglobin levels (P = 0.01), and tended to require fewer red cell units overall (28 vs. 47 units). In patients with intraoperative blood loss > or =800 mL, ANH reduced not only the allogeneic red cell transfusion rate (18.2% vs. 42.4%, P = 0.045) but also the proportion of patients requiring fresh frozen plasma (21.1% vs. 48.3%, P = 0.025). For patients undergoing major liver resection, ANH is safe, effectively reduces the need for allogeneic transfusions, and should be considered for routine use. Given the modest transfusion rate in the STD arm, future efforts should attempt to target ANH use to patients most likely to benefit.

Acute normovolemic hemodilution, intraoperative cell salvage and PulseCO hemodynamic monitoring in a Jehovah’s Witness with placenta percreta

A Jehovah's Witness who had had four previous cesarean deliveries was referred to our institution for management of a complete placenta previa at 34 weeks of gestation. A subsequent ultrasound scan was suggestive of placenta percreta with bladder involvement. After erythropoietin and iron supplementation, cesarean hysterectomy was performed. Using PulseCO technology for continuous hemodynamic monitoring, preoperative acute normovolemic hemodilution and intraoperative cell salvage were used resulting in a successful cesarean hysterectomy with a 5500-mL estimated blood loss. The PulseCO system provides continuous, real-time hemodynamic data by applying pulse power analysis to the arterial pressure waveform. A bolus of oxytocin given after delivery produced profound hypotension, the hemodynamics of which were elucidated with the PulseCO system. To our knowledge, the combined use of acute normovolemic hemodilution, intraoperative cell salvage and PulseCO hemodynamic monitoring for cesarean hysterectomy has not been reported previously. These techniques may be particularly useful in managing patients who refuse blood products and/or in whom the baseline hemoglobin is suboptimal.

Use of acute normovolemic hemodilution in patients undergoing radical prostatectomy

Objectives To evaluate the efficacy and safety of acute normovolemic hemodilution (ANH) in patients undergoing radical prostatectomy. Preoperative autologous blood donation (PAD) is widely accepted as a means of reducing the need for allogeneic blood transfusion in radical prostatectomy. ANH is an alternative method for obtaining autologous blood. Methods On the basis of our previous report that showed the equivalence of PAD and ANH, we prospectively replaced PAD with ANH as a standard practice for radical prostatectomy after September 1999. Of 174 radical prostatectomy patients between September 1999 and June 2004, 153 underwent ANH alone, 15 chose to receive both PAD and ANH, and ANH was contraindicated in 15 because of comorbidities. Results For the 153 patients undergoing ANH alone, 1032 ± 201 mL of autologous blood was collected. With an intraoperative blood loss of 1602 ± 926 mL, 14 patients (9.2%) received allogeneic blood transfusion. The preoperative, intraoperative nadir, and postoperative hematocrit value was 43.6% ± 3.4%, 25.8% ± 3.8%, and 31.9% ± 4.3%, respectively. No patient experienced a perioperative adverse event related to hemodilution or blood transfusion. Conclusions Our continued experience has shown that ANH is a safe and effective means of autologous blood procurement. Given its advantages, including lower cost, lower risk, and simplicity, we conclude that ANH can replace conventional PAD for use in radical prostatectomy, although the true value of ANH should be determined by future randomized studies including a no-treatment control group.

Acute Normovolemic Hemodilution: A Critical Evaluation of Its Safety and Utility in Pediatric Patients

SummaryThe use of blood conservation techniques has gained importance since the 1980s when hazards of blood transfusion, especially transfusion of infectious agents, became well recognized. In adult medicine, predonation autologous blood donation (PABD) and techniques of intraoperative and postoperative collection and reinfusion, initially perfected during the Vietnam era, were used with increased frequency. Methods to limit homologous transfusion in pediatrics were slow to develop, at least in part due to limitations of venous access, operational complexity and the unique and ever changing physiology of the infant and toddler. Blood conservation techniques include PABD, intraoperative hemodilution, intraoperative blood recovery and postoperative scavenging. The history and physiology of hemodilution and its application in pediatric surgery patients with and without additional conservation methods in different clinical conditions will be discussed. In particular, the use of acute normovolemic hemodilution in pediatrics will be the focus of this review.