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Flow diagram outlining study protocol. ANH, acute normovolemic hemodilution, CPB, cardiopulmonary bypass
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Background
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...
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Objective
Dimethyl sulfoxide cryopreserved platelets are being evaluated for treatment of acute hemorrhage in patients with thrombocytopenia or platelet dysfunction when liquid stored platelets are unavailable. Patients undergoing cardiac surgery with cardiopulmonary bypass with risk factors for significant bleeding represent a population for which...
Citations
... Chronic liver stasis can result in hepatic dysfunction and coagulation disorders [6]. When combined with the coagulation dysfunction caused by CPB, the presence of an underlying coagulopathy can significantly increase the surgical risk [7,8]. A recent meta-analysis with 2,114 patients showed that the operative mortality of CP was 6.9% [11]. ...
Background
Constrictive pericarditis (CP) is an uncommon disease that limits both cardiac relaxation and contraction. Patients often present with right-sided heart failure as the pericardium thickens and impedes cardiac filling. Pericardiectomy is the treatment of choice for improving hemodynamics in CP patients; however, the procedure carries a high morbidity and mortality, and the anesthetic management can be challenging. Acute heart failure, bleeding and arrhythmias are all concerns postoperatively.
Methods
After IRB approval, we performed the retrospective analysis of 66 consecutive patients with CP who underwent pericardiectomy from July 2018 to May 2022.
Results
Most patients had significant preoperative comorbidities, including congestive hepatopathy (75.76%), New York Heart Association Type III/IV heart failure (59.09%) and atrial fibrillation (51.52%). Despite this, 75.76% of patients were extubated within the first 24 h and all but 2 of the patients survived to discharge (96.97%).
Conclusions
Anesthetic management, including a thorough understanding of the pathophysiology of CP, the use of advanced monitoring and transesophageal echocardiography (TEE) guidance, all played an important role in patient outcomes.
... The ability of TEG parameters to predict bleeding was questionable in the literature as some studies showed that the use of TEG-MA, TEG R-time, TEG-K, and TEG α-angle was also predictive of blood loss during the operation [75,[79][80][81][82][83][84][85][86][87][88] and even postoperatively [89][90][91][92][93][94][95][96]. They could also predict short-term bleeding complications and micro-bleeding [97,98]. ...
Assessing coagulation status is essential for prompt intervention to reduce morbidity and mortality related to bleeding and thrombotic complications during the perioperative period. Traditional coagulation tests such as platelet count, activated partial thromboplastin time (aPTT), prothrombin time (PT), international normalized ratio (INR), and activated clotting time (ACT) provide only static evaluation. These tests are not designed for assessment of dynamically changing coagulation conditions during the perioperative time. However, viscoelastic coagulation testing such as thromboelastography (TEG) produces a rapid numerical and graphical representation that helps to detect and direct targeted hemostatic therapy. Searching the literature through PubMed, Medline, Ovid, CINAHL, and ClinicalTrials.gov we retrieved 210 studies, which represent the use of TEG in the perioperative period. The included studies were categorized under various settings such as trauma, obstetrics, orthopedics, intensive care unit (ICU), cardiovascular, transplant, and miscellaneous scenarios. TEG showed promising results in trauma surgeries in predicting mortality, hypercoagulability, and bleeding even when it was compared to conventional methods. TEG was also useful in monitoring anticoagulant therapy in orthopedic and obstetric surgeries; however, its role in predicting thrombotic events, hypercoagulability, or complications was questionable. In ICU patients, it showed promising results, especially in the prediction or improvement of sepsis, coagulopathy, thrombotic events, ICU duration, hospital stay, and ventilator duration. TEG parameters effectively predicted hypercoagulation in transplant surgeries. Regarding cardiovascular surgeries, they were effective in the prediction of the need for blood products, coagulopathy, thrombotic events, and monitoring anticoagulation therapy. More randomized clinical trials comparing TEG parameters with standardized tools are needed to produce robust results to standardize its use in different perioperative settings.
... Recommended perioperative blood management protocols include increasing the hemoglobin (Hb) level preoperatively, achieving blood conservation with adjunctive hemostasis intraoperatively, and managing vitals postoperatively [2]. Pre-CPB acute normovolemic hemodilution (ANH) is effective for intraoperative blood conservation because it preserves the Hb, platelets, and coagulation factors consumed or diluted due to CPB [3]. Herein, we have described the successful case of a JW patient who underwent combined cardiac surgery under CPB following ANH. ...
... Several studies have reported the efficacy of ANH against coagulation. For example, ANH reportedly improved the aPTT and fibrinogen levels slightly in cardiac surgery under CPB [3]. In thoracic aortic surgery, ANH improved the PT-INR, platelet count, and fibrinogen levels and reduced the transfusion of fresh frozen plasma and platelet concentrate [15]. ...
Combined cardiac surgery under cardiopulmonary bypass (CPB) has a high risk of requiring blood transfusion. Performing this surgery on Jehovah's Witnesses (JWs) is challenging as they strictly refuse allogeneic blood transfusions due to their religious beliefs.
A 73-year-old female JW patient underwent combined surgery involving coronary artery bypass grafting and mitral valvuloplasty under CPB. Preoperative hematopoiesis maintained the hemoglobin (Hb) level at >12 g/dL preoperatively; the Hb level was maintained at >7 g/dL during CPB for effective acute normovolemic hemodilution (ANH). Compared with the values obtained immediately after CPB weaning, the Hb level and coagulation functions (measured using viscoelastic tests) improved after autologous transfusion at the end of the surgery.
When cardiac surgery under CPB is performed on JWs, ANH can be useful for maintaining postoperative Hb levels and coagulation factors. Sufficient preoperative hematopoiesis and determination of an appropriate volume for intraoperative ANH may be important for effective ANH.
... Those findings are consistent with previously published results. 21,22,24 As fibrinogen in both groups was over 200 mg/dl, it is unclear if the statistical difference also translates into significant biological difference, and particularly so in absence of significant clinical bleeding. Importantly, we found no significant difference in the 12-hour chest tube output or rate of reoperation for bleeding in the studied cohorts. ...
Background:
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.
Study design and methods:
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.
Results:
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.
Discussion:
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.
... Strategies that can minimise haemodilution may include the use of miniaturised CPB circuits (mini-CPB), retrograde autologous priming of the CPB, and ultrafiltration [50,51]. As a measure of blood conservation during CPB, acute normovolemic haemodilution [51], although causing haemodilution and lower haematocrit during CPB, has been shown to significantly improve the fibrinogen concentration after reinfusion [52]. ...
Background: Fibrinogen is a substrate for blood clots formation. In cardiac surgery, a number of different mechanisms lead to a decrease in fibrinogen levels and consequent impaired haemostasis. Patients undergoing cardiac surgery are therefore frequently exposed to blood loss and allogeneic blood transfusion, which are risk factors associated with morbidity and mortality. Thus, particular efforts in fibrinogen management should be made to decrease bleeding and the need for blood transfusion. Therefore, fibrinogen remains an active focus of investigations from basic science to clinical practice. This review aims to summarise the latest evidence regarding the role of fibrinogen and current practices in fibrinogen management in adult cardiac surgery. Methods: The PubMed database was systematically searched for literature investigating the role and disorders of fibrinogen in cardiac surgery and diagnostic and therapeutic procedures related to fibrinogen deficiency aimed at reducing blood loss and transfusion requirements. Clinical trials and reviews from the last 10 years were included. Results: In total, 146 articles were analysed. Conclusion: The early diagnosis and treatment of fibrinogen deficiency is crucial in maintaining haemostasis in bleeding patients. Further studies are needed to better understand the association between fibrinogen levels, bleeding, and fibrinogen supplementation and their impacts on patient outcomes in different clinical settings.
... Interestingly, studies performed in cardiac surgeries other than aortic repairs suggest no clinically significant improvement in coagulation results. 9 In this study we evaluated whether ANH improved coagulation and/or reduced allogeneic blood transfusion in surgical repairs of thoracic aortic aneurysms or dissections. We also assessed safety of this technique by analyzing multiple outcome measures. ...
... A degree of "auto correction" of coagulation results has been described in literature, and was not specifically addresses in our study, as in the control group we only obtained one post-CPB sample. 9 In the ANH group, the second laboratory sample was obtained Overall, ANH was associated with a reduced amount of transfused allogeneic blood, but did not reduce the proportion of patients exposed to allogeneic blood intraoperatively. Some individuals may be more prone to ...
Background and aim:
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.
Methods:
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.
Results:
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.
Conclusions:
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.
... 95% CI 0.1-0.8; p = 0.024) and fibrinogen levels (236 mg/dL v 221 mg/dL [167-275], 95% CI 1-26; p = 0.04) in the ANH group after inverse probability treatment weighting and controlling for the value of timepoint 1. 79 The aPPT level (29.7 [24.8-34.6] v 27.7 [24.2-31.2], ...
This is the second annual review in the Journal of Cardiothoracic and Vascular Anesthesia to cover highlights in coagulation for cardiac surgery. The goal of this article is to provide readers with a focused summary of the prior year's most important coagulation topics from the literature. In 2020, this includes a discussion covering allogeneic transfusion, antiplatelet and anticoagulant therapy, factor concentrates, coagulation testing, mechanical circulatory support, and the impact of COVID-19.
Study objective:
To investigate whether large volume acute normovolemic hemodilution (L-ANH), compared with moderate acute normovolemic hemodilution (M-ANH), can reduce perioperative allogeneic blood transfusion in patients with intermediate-high risk of transfusion during cardiac surgery with cardiopulmonary bypass (CPB).
Design:
Prospective randomized controlled trial.
Setting:
University hospital.
Patients:
Patients with transfusion risk understanding scoring tool ("TRUST") ≥2 points undergoing cardiac surgery with CPB in the Second Affiliated Hospital of Zhejiang University from May 2020 to January 2021 were included.
Interventions:
The patients were randomly assigned with a 1:1 ratio to M-ANH (5 to 8 mL/kg) or L-ANH (12 to 15 mL/kg).
Measurements:
The primary outcome was perioperative red blood cell (RBC) transfusion units. The composite outcome included new-onset atrial fibrillation, pulmonary infection, cardiac surgery associated acute kidney injury (CSA-AKI) class ≥2, surgical incision infection, postoperative excessive bleeding, and resternotomy.
Main results:
Total 159 patients were screened and 110 (55 L-ANH and 55 M-ANH) were included for final analysis. Removed blood volume of L-ANH is significantly higher than M-ANH (886 ± 152 vs. 395 ± 86 mL, P < 0.001). Perioperative RBC transfusion was median 0 unit ([25th, 75th] percentiles: 0-4.4) in M-ANH group vs. 0 unit ([25th, 75th] percentiles: 0-2.0) in L-ANH group (P = 0.012) and L-ANH was associated with lower incidence of transfusion (23.6% vs. 41.8%, P = 0.042, rate difference: 0.182, 95% confidence interval [0.007-0.343]). The incidence of postoperative excessive bleeding was significantly lower in L-ANH vs. M-ANH (3.6% vs. 18.2%, P = 0.029, rate difference: 0.146, 95% confidence interval [0.027-0.270]) without significant difference for other second outcomes. The volume of ANH was inversely related to perioperative RBC transfusion units (Spearman r = -0.483, 95% confidence interval [-0.708 to -0.168], P = 0.003), and L-ANH in cardiac surgery was associated with a significantly reduced risk of perioperative RBC transfusion (odds ratio: 0.43, 95% confidence interval: 0.19-0.98, P = 0.044).
Conclusions:
Compared with M-ANH, L-ANH during cardiac surgery inclined to be associated with reduced perioperative RBC transfusion and the volume of RBC transfusion was inversely proportional to the volume of ANH. In addition, LANH during cardiac surgery was associated with a lower incidence of postoperative excessive bleeding.
Background
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.
Study Design and Methods
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 (CPB).
Results
Intraoperatively, the ANH group received more albumin ( p =0.04) and vasopressor medications ( p =0.01); while urine output was no different between ANH and controls. Bilateral cerebral oximetry (rSO 2 ) values were similar before and after hemodilution. During bypass rSO 2 were discretely lower in the ANH vs. control group (right rSO 2 p= 0.03, left rSO 2 ( p =0.05). No differences in lactic acid values were detected across the procedural continuum. Postoperatively, no differences in extubation times, ICU length of stay, kidney injury, stroke or infection were demonstrated.
Discussion
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.
