Acute Normovolemic Hemodilution Group Research Articles

Acute Normovolemic Hemodilution (ANH) impacts postoperative coagulation profile and bleeding in Adult Cardiac Surgery

Introduction: The coagulation profile of cardiac surgery patients is impacted by pro-inflammatory effects caused by procedures involving cardiopulmonary bypass. In order to counteract these effects, pharmacological therapies and allogeneic blood transfusions are required. The strategy of Acute normovolemic hemodilution also known as “intraoperative autologous donation” is also a viable option to address these negative effects. The theoretical basis for ANH is that the removed blood of a patient’s own self is shielded from the inflammatory response of blood cells to the bypass circuit. ANH is an infrequently practiced strategy at various cardiac surgery institutes within Pakistan to enhance coagulation profile, decrease the need for blood transfusions despite being an established approach abroad. Aims and Objectives: The objective of our study is to compare the effect of ANH on patients undergoing adult cardiac surgery in a sample group versus a control group with the primary endpoint of postoperative drain output as a measure of effectiveness of blood coagulation profile. Blood coagulation profiles were also compared between the two groups as secondary variables. Place and Duration of study: The study was conducted at the Faisalabad Institute of Cardiology from December 21st, 2023 to February 13th, 2024. Material and Methods: A randomized controlled trial involving 60 patients over the age of 12 years who were to undergo adult cardiac surgery was conducted. An online research randomizer software randomly selected them into two equal groups, sample and control (n=30). The ANH volume retrieved from the patient's central vein in the sample group was used to fill the CPD blood transfusion bags after administering anesthesia. After the patients in both groups were weaned off CPB and protamine administered to neutralize heparin, ANH blood was infused back into the patients in the sample group whereas the control group received allogenic blood only. Chi square test was applied to all qualitative variables and Independent Samples t-test for all quantitative variables. The results were analyzed using SPSS version 25, and a p-value ? 0.05 was considered statistically significant. Results: Hemoglobin (12.9±0.90 g/dL in ANH and 11.8±1.00 g/dL in non-ANH) and aPTT levels (34.2±6.06 seconds in ANH and 54.2±10.95 seconds in non-ANH) were statistically significant (p-value <0.01). In the ANH group, the mean value (623.3±86.28 mL) of postoperative drain output significantly decreased by approximately 220mL compared to the non-ANH group (842.3±99.26 mL) (p-value <0.01). Conclusion: ANH positively conserves most of the coagulation profile parameters. It assists in reducing postoperative bleeding and the volume of allogeneic blood required perioperatively in cardiac surgery.

Postoperative long‑term outcomes of acute normovolemic hemodilution in pancreatic cancer: A propensity score matching analysis.

Acute normovolemic hemodilution (ANH) is a useful intraoperative blood conservation technique. However, the impact on long-term outcomes in pancreatic ductal adenocarcinoma (PDAC) remains unclear. The present study investigated the impact of ANH on long-term outcomes in patients with PDAC undergoing radical surgery. Data from 155 resectable PDAC cases were collected. Patients were categorized according to whether or not they had received intraoperative allogeneic blood transfusion (ABT) or ANH. Postoperative complications, recurrence-free survival (RFS) and disease-specific survival (DSS), before and after propensity score matching (PSM), were compared among patients who did and did not receive ANH. A total of 44 patients (28.4%) were included in the ANH group and 30 patients (19.4%) were included in the ABT group; 81 (52.3%) patients, comprising the standard management (STD) group, received neither ANH nor ABT. The ABT group had the worst prognosis among them. Before PSM, ANH was significantly associated with decreased RFS (P=0.043) and DSS (P=0.029) compared with the STD group before applying Bonferroni correction; however, no significant difference was observed after applying Bonferroni correction. Cox regression analysis identified ANH as an independent prognostic factor for RFS [relative risk (RR), 1.696; P=0.019] and DSS (RR, 1.876; P=0.009). After PSM, the ANH group exhibited less favorable RFS [median survival time (MST), 12.1 vs. 18.1 months; P=0.097] and DSS (MST, 32.1 vs. 50.5 months; P=0.097) compared with the STD group; however, these differences were not statistically significant. In conclusion, while ANH was not as harmful as ABT, it exhibited potentially more negative effects on long-term postoperative outcomes in PDAC than STD.

Effect of acute normovolemic hemodilution in patients undergoing cardiac surgery with remimazolam anesthesia.

The reduced effects of allogeneic transfusion with acute normovolemic hemodilution (ANH) have been reported. Harvesting a large volume of blood may maximize the effect in patients with low body weight, and the prevention of hypotension is important. Remimazolam is an anesthetic with few circulatory responses. Our aim was to evaluate whether high-volume ANH reduces the need for transfusion in cardiac patients under remimazolam anesthesia. In this retrospective single-center study, we enrolled cardiopulmonary bypass (CPB) patients who received remimazolam anesthesia. Changes in hemodynamic parameters were assessed. The numbers of blood transfusions and chest tube outputs were also evaluated. In a total of 51 patients, ANH was performed in 27 patients with a mean body mass index of 23.2 (ANH volume: 740 ± 222mL). No significant differences were observed in mean blood pressure during blood collection. The intraoperative amount of red blood cell (RBC) transfusion was significantly lower in the ANH group than in the control group (431 ± 678 and 1260 ± 572mL, p < 0.001). The avoidance rates of RBC were 66.7 and 4.2%, respectively. The multivariate analysis result revealed that ANH correlated with RBC, with an odds ratio of 0.067 (95% confidence interval 0.005-0.84, p < 0.05). The postoperative bleeding at 24h was significantly lower in the ANH group (455 ± 228 and 797 ± 535mL, p < 0.01). In patients undergoing CPB, ANH reduced intraoperative transfusion amount and postoperative bleeding. Hemodynamic changes during blood collection were minimal under remimazolam anesthesia and high-volume ANH was feasible.

Low-Volume Acute Normovolemic Hemodilution Does Not Reduce Allogeneic Red Blood Cell Transfusion in Cardiac Surgery in the Modern Era of Patient Blood Management: A Propensity Score-Matched Cohort Study

Patients undergoing cardiac surgery often require blood transfusions, which are associated with increased morbidity and mortality. Patient blood management (PBM) strategies, including acute normovolemic hemodilution (ANH), have been implemented to minimize allogeneic transfusion requirements. Older studies suggested that ANH is associated with reduced transfusions; however, its effectiveness in the modern era of PBM remains unclear. This was a retrospective cohort study. The study was held at a single university hospital. 542 patients who underwent elective cardiac surgery with cardiopulmonary bypass (CPB) using low-priming-volume circuits between January 2017 and March 2022. Patients who received ANH were matched with those who did not receive ANH, using propensity scores. The primary outcome was the proportion of patients who received perioperative red blood cell (RBC) transfusion. Of the 542 eligible patients, 49 ANH cases were propensity-score matched to 97 controls. The median ANH volume was 450 mL (IQR, 400-800 mL). There was no significant difference in perioperative RBC transfusion rates between the 2 groups (24.5% in the ANH group vs 30.9% in the control group, p=0.42). The odds ratio for perioperative RBC transfusion in the ANH group versus the control group was 0.72 (95% CI, 0.32-1.55, p=0.42). Low-volume ANH was not associated with a significant reduction in perioperative allogeneic RBC transfusion during cardiac surgery with CPB using low-priming-volume circuits. The benefits of low-volume ANH in reducing the requirement for RBC transfusion in the modern era of PBM may be smaller than reported previously.

Effect of acute normovolemic hemodilution on anesthetic effect, plasma concentration, and recovery quality in elderly patients undergoing spinal surgery

ObjectiveTo explore the effect of acute normovolemic hemodilution (ANH) on the anesthetic effect, plasma concentration, and postoperative recovery quality in elderly patients undergoing spinal surgery.MethodsA total of 60 cases of elderly patients aged 65 to 75 years who underwent elective multilevel spinal surgery were assigned randomly into the ANH group (n = 30) and control group (n = 30). Hemodynamic and blood gas analysis indexes were observed and recorded before ANH (T1), after ANH (T2), immediately after postoperative autologous blood transfusion (T3), 10 min (T4), 20 min (T5), 30 min (T6), 40 min (T7), and 50 min (T8) after the transfusion, and at the end of the transfusion (i.e., 60 min; T9). At T3 ~ 9, bispectral index (BIS) and train-of-four (TOF) stimulation were recorded and the plasma propofol/cisatracurium concentration was determined. The extubation time and recovery quality were recorded.ResultsThe ANH group presented a lower MAP value and a higher SVV value at T2, and shorter extubation and orientation recovery time (P < 0.05) compared with the control group. BIS values at T8 and T9 were lower in the ANH group than those in the control group (P < 0.05). TOF values at T7 ~ 9 were lower in the ANH group than those in the control group (P < 0.05). There were no statistically significant differences in the postoperative plasma concentrations of propofol and cisatracurium between the groups (P > 0.05).ConclusionDuring orthopedic surgery, the plasma concentration of elderly patients is increased after autologous blood transfusion of ANH, and the depth of anesthesia and muscle relaxant effect are strengthened, thus leading to delayed recovery of respiratory function and extubation.

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.

Does Autologous Transfusion Decrease Allogeneic Transfusion in Liposuction Surgery of Lymphedema Patients?

Background and ObjectiveLiposuction is an effective treatment for fat disposition in lymphedema. Blood transfusion has been seldom investigated in lymphedema liposuction surgery. The purpose of the study was to analyze clinical factors associated with blood transfusion in liposuction surgery of lymphedema patients and compare the autologous and allogeneic transfusion patterns.MethodsA total of 1,187 cases of liposuction due to lymphedema were recruited. Demographic, laboratory tests and operation information were collected. Patients were divided into a transfusion and a non-transfusion group. Different transfusion patterns were compared and analyzed.ResultsBetween the two groups, there is a significant difference in postoperative hemoglobin levels, and as well as gender, age, surgery duration, body weight change, intraoperative transfusion volume and blood loss, hospital length of stay, and surgical site distribution. There is a significant difference in the comparison of hospital stay length, autologous transfusion volume, combined allogeneic volume, operative blood loss, intraoperative transfusion volume, and change in hemoglobin levels between predonation and acute normovolemic hemodilution (ANH) transfusion. In comparison with the allogeneic transfusion-only patients, the mean allogeneic transfusion volume in either ANH group, predonated transfusion group, or mixed group is statistically lower. Allogeneic transfusion volume in the predonated-only group is significantly lower than that of either the ANH-only group or the mixing ANH with predonation group. Ordinary least squares regression analysis suggests that autologous transfusion in the ANH-only mode is statistically associated with allogeneic transfusion.ConclusionsThis study described the blood transfusion in lymphedema liposuction surgery and compared autologous and allogeneic transfusion patterns in these patients. Autologous transfusion can reduce the transfusion volume of allogeneic blood and might be a beneficial mode of transfusion in these patients.

Hemodilution in high-risk cardiac surgery: Laboratory values, physiological parameters, and outcomes.

Acute normovolemic hemodilution (ANH) is a blood conservation strategy in cardiac surgery, predominantly used in coronary artery bypass graft (CABG) and/or valve procedures. Although higher complexity cardiac procedures may benefit from ANH, concerns for hemodynamic instability, and organ injury during hemodilution hinder its wider acceptance. Laboratory and physiological parameters during hemodilution in complex cardiac surgeries have not been described. This observational cohort (2019-2021) study included 169 patients who underwent thoracic aortic repair, multiple valve procedure, concomitant CABG with the aforementioned procedure, and/or redo sternotomies. Patients who received allogeneic blood were excluded. Statistical comparisons were performed between ANH (N=66) and non-ANH controls (N=103). ANH consisted of removal of blood at the beginning of surgery and its return after cardiopulmonary bypass. Intraoperatively, the ANH group received more albumin (p=.04) and vasopressor medications (p=.01), while urine output was no different between ANH and controls. Bilateral cerebral oximetry (rSO2 ) values were similar before and after hemodilution. During bypass, rSO2 were discretely lower in the ANH versus control group (right rSO2 p =.03, left rSO2 p=.05). No differences in lactic acid values were detected across the procedural continuum. Postoperatively, no differences in extubation times, intensive care unit length of stay, kidney injury, stroke, or infection were demonstrated. This study suggests hemodilution to be a safe and comparable blood conservation technique, even without accounting for potential benefits of reduced allogenic blood administration. The study may contribute to better understanding and wider acceptance of ANH protocols in high-risk cardiac surgeries.

Acute normovolemic hemodilution in combination with tranexamic acid is an effective strategy for blood management in lumbar spinal fusion surgery

BackgroundThe retrospective study was designed to compare the effectiveness and safety of acute normovolemic hemodilution (ANH), tranexamic Acid (TXA), and a combination of ANH and TXA in lumbar spinal fusion surgery.MethodsData of 120 patients underwent multi-level posterior spinal fusion for treating degenerative lumbar disease between June 2013 and December 2017 was collected, retrospectively. Four treatment strategies were enrolled, including ANH, TXA, a combination of ANH and TXA, and without any patient blood management. Intraoperative blood loss, hemoglobin and PCV at the end of surgery and at the postoperative first day, and postoperative drain collection, and intraoperative and postoperative transfusion and rate of transfusion were also collected.ResultsIntraoperative blood loss and postoperative drain collection of the TXA group, ANH combined with TXA group were statistically lower than those in the control group and ANH group (P < 0.05). Intraoperative and postoperative transfusion amount and rate of intra-operative allogenic transfusion of the ANH group, TXA group, and ANH combined with TXA group were statistically lower than those of the control group (P < 0.05). Hemoglobin and PCV at postoperative the first day in the ANH group, TXA group, and ANH combined with TXA group were significant higher than those in the control group (P < 0.05). The combination of TXA and ANH group achieved the lowest intraoperative blood loss, postoperative drain collection and allogenic transfusion rate.ConclusionA combination of TXA and ANH might be an effective strategy for reducing the rate of transfusion and blood loss in patients underwent lumbar spinal fusion surgery.

Effects of acute normovolemic hemodilution on post‐cardiopulmonary bypass coagulation tests and allogeneic blood transfusion in thoracic aortic repair surgery: An observational cohort study

Perioperative blood transfusion is associated with increased morbidity and mortality. Acute normovolemic hemodilution (ANH) is a blood conservation strategy associated with variable success, and rarely studied in more complex cardiac procedures. The study aim was to evaluate whether ANH improves coagulopathy and reduces blood transfusions in thoracic aortic surgeries. Single-center observational cohort study comparing ANH and standard institutional practice in patients who underwent thoracic aortic repair with cardiopulmonary bypass (CPB) from 2019 to 2021. A total of 89 patients underwent ANH and 116 standard practice. There were no significant differences between the groups in terms of demographic or major perioperative characteristics. In the ANH group coagulation tests before and after transfusion of autologous blood showed decreased INR and increased platelets, fibrinogen, all with p < 0.0005. Coagulation results in the ANH and control groups were not statistically different. The average number of transfused allogeneic products per patient was lower in the ANH versus control group: FFP 1.1 ± 1.6 versus 1.9 ± 2.3 (p = 0.003), platelets 0.6 ± 0.8 versus 1.2 ± 1.3 (p = 0.0008), and cryoprecipitate 0.3 ± 0.7 versus 0.7 ± 1.1 (p = 0.008). Reduction in red blood cell transfusion was not statistically significant. The percentage of patients who received any transfusion was 53.9% in ANH and 59.5% in the control group (p = 0.42). There was no significant difference in major adverse outcomes. ANH is a safe blood conservation strategy for surgical repairs of the thoracic aorta. Laboratory data suggests ANH can improve some coagulation values after separation from CPB, and significantly reduce the number of transfused FFP, platelets and cryoprecipitate.

Association of acute normovolemic hemodilution with decreased length of hospital stay in rhesus-negative patients undergoing major cancer surgeries: a retrospective study.

Shortages of allogeneic blood supplies for rhesus (Rh)-negative patients who are scheduled for major cancer surgeries may cause delays in surgical procedure, resulting in a prolonged length of hospital stay (LOHS). This study investigated the relationship of acute normovolemic hemodilution (ANH) with LOHS in this patient population. Rh-negative patients who underwent major cancer surgeries between January 2015 and April 2020 were included in this retrospective study. The primary outcome was LOHS. The secondary outcomes were length of preoperative stay (LOPS), perioperative laboratory data and allogeneic blood transfusion (ABT), and postoperative adverse events. Furthermore, relationships between these perioperative variables and LOHS were examined by both univariate analyses and multiple linear regression analysis. Seventy patients were divided into ANH (n=30) or Control (n=40) group. The two groups were well-matched for baseline data. LOHS, LOPS, perioperative ABT amount, and the overall rate of postoperative adverse events were all significantly lower in the ANH group (P=0.004, P=0.009, P<0.001, P=0.023, respectively). In the ANH group, levels of hemoglobin and hematocrit decreased on postoperative day 1 (P=0.023, P=0.012, respectively). Univariate analyses revealed significant association between LOHS and the following perioperative variables: ANH, body mass index, types of surgery, intraoperative colloids infusion, and perioperative ABT. Multiple linear regression analysis with correction for diagnosis identified ANH, intraoperative colloids infusion, and perioperative ABT as independent predictors. ANH was associated with the decreased LOHS in Rh-negative patients undergoing major cancer surgeries.

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.

Survival outcomes of acute normovolemic hemodilution in patients undergoing primary debulking surgery for advanced ovarian cancer: A Memorial Sloan Kettering Cancer Center Team Ovary study

ObjectiveTo describe oncologic outcomes after using acute normovolemic hemodilution (ANH) to reduce requirement for allogenic red blood cell transfusions (ABT) in patients undergoing primary debulking surgery (PDS) for advanced ovarian cancer. MethodsWe performed a post-hoc analysis of a recent prospective trial investigating the safety and feasibility of ANH during PDS for advanced ovarian cancer. We report long-term survival outcomes. We compared demographics, clinicopathological characteristics, survival outcomes in this cohort of Stage IIIB-IVB high-grade serous ovarian cancer patients undergoing ANH (ANH group), with a retrospective cohort of all other patients (standard group) undergoing PDS during the same time period (01/2012–04/2017). Standard statistical tests were used. ResultsThere were no demographic or clinicopathological differences between ANH (n = 33) and standard groups (n = 360), except for higher median age at diagnosis (57 vs. 62 years, respectively; p = 0.044) and shorter operative time (357 vs. 446 min, respectively; p < 0.001) in the standard group. Cytoreductive outcomes (ANH vs. standard): 0 mm, 69.7 vs. 63.9%; gross residual disease (RD) ≤1 cm, 21.2 vs. 26.9%; >1 cm, 9.1 vs. 9.2% (p = 0.78). RD after PDS was the only independent factor associated with worse progression-free survival (PFS) on multivariable analysis (p < 0.001). Patients with BRCA mutations trended towards improved PFS (p = 0.057). Significant factors for overall survival (OS) on multivariable analysis: preoperative CA125 (p = 0.004), ascites (p = 0.018), RD after PDS (p = 0.04), BRCA mutation status (p < 0.001). After adjustment for potential confounders, ANH was not independently associated with PFS or OS [PFS: HR 0.928 (0.618–1.395); p = 0.721; OS: HR 0.588 (95%CI: 0.317–1.092); p = 0.093]. ConclusionsANH is an innovative approach in intraoperative management. It was previously proven to decrease need for ABT while maintaining the ability to achieve complete gross resection and associated benefits.

Effect of acute normovolemic hemodilution on coronary artery bypass grafting: A systematic review and meta-analysis of 22 randomized trials.

Efficacy of minimal acute normovolemic hemodilution (ANH) in avoiding homologous blood transfusion during cardiovascular surgery remains controversial. Postoperative bleeding and transfusion remain a source of morbidity and cost after open heart operations. To better understand the role of acute normovolemic hemodilution (ANH) in coronary artery bypass grafting (CABG), we compared ANH with standard intraoperative care in a systematic review including a standard pairwise meta-analysis of randomized controlled trials (RCTs). We searched the Cochrane Library, PubMed, EMBASE, Web of Science and Chinese National Knowledge Infrastructure (CNKI) up to April 1, 2020. The primary outcome was to assess the incidence of ANH-related number of allogeneic red blood cell units (ARBCu) transfused. Secondary outcomes included the rate of allogeneic blood transfusion and estimated total blood loss. A total of 22 RCTs including 1688 patients were identified for the present meta-analysis. Of these studies, 19 were about CABG with on-pump and three with off-pump. Our pooled result indicated that patients received ANH experienced fewer ARBCu transfusions, with a standardized mean difference (SMD) of -0.60 (95%CI -0.96 to -0.24; P=0.001). The rate of allogeneic blood transfusion in ANH group was significant reduced when compared with controls, with a relative risk (RR) of 0.65 (95%CI 0.52 to 0.82; P=0.0002). In addition, less postoperative estimated total blood loss was present, with a SMD of -0.53 (95%CI -0.88 to -0.17; P=0.004). The present meta-analysis indicated that ANH could reduce the number of ARBCu transfused in the CABG surgery setting. In addition, ANH could also reduce the rate of ARBCu transfusion and estimated total blood loss for CABG patients.

Acute normovolemic hemodilution in major orthopedic surgery

BackgroundWith increasing concerns regarding the newer emerging pathogens, alternatives to allogeneic blood transfusion are being explored and acute normovolemic hemodilution (ANH) is one of them. MethodsA prospective study was conducted in patients aged 18–65 years with preoperative hemoglobin >12 g/dl undergoing total knee replacement or total hip replacement. Patients in whom hemodilution was performed were included in the ANH group whereas patients undergoing treatment as per the routine hospital protocol were included in the control group. ResultsPreoperative hemoglobin was similar in both ANH and control groups (12.7 ± 0.7 vs 12.6 ± 0.6, p = 0.56). Allogeneic blood requirement was significantly less in the ANH group as compared to the control group (4 vs 15, p = 0.001). Postoperative complications were significantly lower in ANH group as compared to control group (7 vs 16, p = 0.01). ConclusionsANH can be an alternative approach to meet the need of safe blood especially in resource constrained countries, like India where risk of transfusion transmitted infections are still high and where there is high demand of blood and acute shortage of blood in hospitals.

Coagulation test changes associated with acute normovolemic hemodilution in cardiac surgery.

Patients undergoing cardiac surgery requiring cardiopulmonary bypass (CPB) are at risk for coagulopathy and bleeding requiring blood product transfusion. Acute normovolemic hemodilution (ANH) is a blood conservation technique shown to reduce transfusion and bleeding associated with cardiac surgery. Despite numerous advantages, little is known about the effect of ANH on coagulation testing. Prospective observational study, 80 patients (40 controls, 40 ANH) undergoing cardiac surgery requiring CPB. Blood for coagulation testing (hemoglobin, platelet count, prothrombin time/International Normalized Ratio [PT/INR], activated partial thromboplastin time [aPTT], fibrinogen, and kaolin thromboelastography [TEG]) was collected 5 minutes after protamine (Time 1), and following ANH reinfusion (or 30 minutes after Time 1) in controls (Time 2). Patients undergoing ANH had a significantly lower aPTT (-1.4 seconds 95% CI [-2.7, 0.0]; P = .044) and higher fibrinogen (+13 mg/dL [+1, +26]; P = .040) between Time 1 and Time 2 compared to controls. Additionally, the change in hemoglobin between Time 1 and Time 2 was significantly increased in the ANH group (+0.4 [+0.1, +0.8]; P = .024). The study also demonstrated a normalization of the platelet count, PT/INR, aPTT, and TEG values between Time 1 and Time 2 in control patients. In patients undergoing cardiac surgery requiring CPB, ANH results in significant improvements of aPTT, fibrinogen and hemoglobin values; however, the true clinical significance is questionable. In the absence of ongoing surgical bleeding, there appears to be normalization of coagulation tests (excluding fibrinogen) following CPB.

Safety and efficacy of acute normovolemic hemodilution during liver surgery: a Meta-analysis

Abstract Objective The aim of this study was to evaluate the safety and efficacy of acute normovolemic hemodilution (ANH) during liver surgery. Methods Structured searches of the PubMed, Chinese Biological Medicine Database, and Cochrane Library electronic databases were performed, followed by a meta-analysis of outcomes, including intraoperative blood transfusion(s), intraoperative bleeding, postoperative hematocrit (Hct) levels, postoperative prothrombin time (PT), and number of patients who underwent transfusions during liver surgery. Results In total, 14 eligible studies were included in the meta-analysis, which revealed that ANH for liver resection was associated with a reduction in intraoperative blood transfusions [weighted mean difference (WMD) -1.99; 95% confidence interval (CI) -2.82 to -1.16; P &lt; 0.00001]. The ANH group experienced less intraoperative bleeding (WMD -72.81; 95% CI -136.12 to -9.50; P &lt; 0.00001) and exhibited a lower postoperative Hct level (WMD -3.38; 95% CI -7.14 to -0.67; P &lt; 0.00001) than the control group. Moreover, meta-analysis revealed that postoperative prothrombin time was not affected by ANH (WMD -0.02; 95% CI -0.18 to -0.32; P = 0.65). Finally, the number of patients requiring allogeneic transfusion was significantly smaller in the ANH group than in the control group (odds ratio 0.13; 95% CI 0.09 to 0.18; P = 0.24). Conclusion Results of the present meta-analysis indicated that ANH can reduce intraoperative bleeding and the need for blood transfusions. In addition, ANH did not negatively affect the coagulation system after surgery; therefore, ANH appears to be safe and effective during liver surgery.

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.

Impact of intraoperative high-volume autologous blood collection on allogeneic transfusion during and after cardiac surgery: a propensity score matched analysis.

Perioperative use of allogeneic blood products is associated with higher morbidity, mortality, and hospital costs after cardiac surgery. Blood conservation techniques such as acute normovolemic hemodilution (ANH) report variable success. We hypothesized that large-volume ANH with limited hemodilution would reduce allogeneic blood transfusion compared to the standard practice. Retrospective observational study of cardiac surgery patients at the University of Maryland Medical Center between January 2014 and September 2017. Using the institutional Society of Thoracic Surgeons database 91 autologous and 981 control patients who underwent coronary artery bypass grafting, aortic valve replacement, or both were identified. After propensity matching of 13 preoperative characteristics, 84 autologous and 84 control patients were evaluated. Our primary endpoint was avoidance of blood transfusion during index hospitalization, and secondary endpoints were postoperative bleeding and major adverse outcomes. The median harvest volumes in the ANH and control groups were 1100 mL and 400 mL, respectively. Of the ANH group, 25% received any transfusion versus 45.2% of the control group after propensity score matching (p < 0.006). When controlling for preoperative platelet count, the transfusion rate ratios for ANH were 0.58 (95% confidence interval, 0.39-0.88) for RBCs and 0.63 (0.44-0.89) for non-RBC components, which were both found to be statistically significant. There was no difference found in major adverse events. These results suggest that large-volume ANH is beneficial in reducing both RBC and non-RBC component usage in cardiac surgery. A further prospective validation is warranted.

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.