Treatment Strategies in Anemic Patients Before Cardiac Surgery

"Detect Anemia Preoperatively": A Scoping Review of Recommendations

Background

Preoperative anemia significantly impacts patient outcomes, prompting increasing global implementation of patient blood management (PBM) measures. Timely diagnosis and differentiation of preoperative anemia are crucial components of PBM to maximize its effectiveness. Despite this, comprehensive implementation remains inconsistent. This scoping review aims to give an overview of recommendations regarding preoperative anemia management to detect gaps in knowledge and emerging ideas.

Methods

A scoping review, adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, investigated preoperative anemia detection, focusing on patient population, timing, extent, and process of investigations. PubMed and ScienceDirect were searched for English and German articles published in the last 5 years, supplemented by manual selection. Pediatric and obstetric recommendations were excluded. Results were synthesized based on key questions.

Results

Four hundred sixty-five articles were screened, and 80 met the inclusion criteria, including 25 clinical practice guidelines. Most (n = 62) suggested "detect and correct" anemia without further specification. The rest advised conducting investigations early, ideally up to 30 days before major procedures with expected blood loss >500 mL. Recommended tests include blood counts, various iron parameters, folic acid/vitamin B12, inflammation markers, and renal, hepatic, and thyroid function tests. Ten articles described detailed algorithms. Other key recommendations included using reticulocyte hemoglobin, point-of-care Hb measurements, and automated laboratory algorithms. The underlying quality of scientific evidence is heterogeneous.

Conclusions

International recommendations on the detection of preoperative anemia are heterogeneous and often generic. Automated algorithms could make a significant contribution to practicability. While practice-oriented guidelines, especially by surgical societies, could promote standardized and efficient implementation, further research is needed to improve the quality of underlying scientific evidence.

Case Report: "Dumbbell" giant right coronary artery ectasia with right atrial fistula

A 50-year-old female patient presented with a "dumbbell" giant right coronary artery ectasia, characterized by two artery dilation segments both reaching the level of a giant aneurysm with a normal segment between them. Computed tomography angiography showed a fistula sac in the right atrium. The vessel shape was a typical type IV (localized or segmental) coronary artery ectasia, which is rarely seen on true imaging. The patient had a 3-year history of chest tightness, without dyspnea, worsened by physical activity. Additional tests indicated that she had mitral valve regurgitation, superficial myocardial bridge, and anemia, all of which led to the development of her symptoms. She felt relieved after successful coronary artery fistula repair, mitral valvuloplasty, and fistula sac removal. At the 6-month follow-up, no complications were found according to echocardiography. Patients with coronary aneurysms can be asymptomatic in the early stage, while this case indicates that the dumbbell shape may be a developing stage of giant coronary aneurysm whose origin and close-fistula segments are influenced by separate hydrodynamics during ectasia or aneurysm formation.

Prognostic models for prediction of perioperative allogeneic red blood cell transfusion in adult cardiac surgery: A systematic review and meta-analysis

OBJECTIVES

Identifying cardiac surgical patients at risk of requiring red blood cell (RBC) transfusion is crucial for optimizing their outcome. We critically appraised prognostic models preoperatively predicting perioperative exposure to RBC transfusion in adult cardiac surgery and summarized model performance.

METHODS

Design: Systematic review and meta-analysis.

STUDY ELIGIBILITY CRITERIA

Studies developing and/or externally validating models preoperatively predicting perioperative RBC transfusion in adult cardiac surgery. Information sources MEDLINE, CENTRAL & CDSR, Embase, Transfusion Evidence Library, Web of Science, Scopus, ClinicalTrials.gov, and WHO ICTRP. Risk of bias and applicability: Quality of reporting was assessed with the Transparent Reporting of studies on prediction models for Individual Prognosis or Diagnosis adherence form, and risk of bias and applicability with the Prediction model Risk of Bias ASsessment Tool.

SYNTHESIS METHODS

Random-effects meta-analyses of concordance-statistics and total observed:expected ratios for models externally validated ≥5 times.

RESULTS

Nine model development, and 27 external validation studies were included. The average TRIPOD adherence score was 66.4% (range 44.1%-85.2%). All studies but 1 were rated high risk of bias. For TRUST and TRACK, the only models externally validated ≥5 times, summary c-statistics were 0.74 (95% CI: 0.65-0.84; 6 contributing studies) and 0.72 (95% CI: 0.68-0.75; 5 contributing studies) respectively, and summary total observed:expected ratios were 0.86 (95% CI: 0.71-1.05; 5 contributing studies) and 0.94 (95% CI: 0.74-1.19; 5 contributing studies), respectively. Considerable heterogeneity was observed in all meta-analyses.

DISCUSSION

Future high quality external validation and model updating studies which strictly adhere to reporting guidelines, are warranted.

The Year in Cardiothoracic and Vascular Anesthesia: Selected Highlights from 2024

This special article is the 17th in an annual series for the Journal of Cardiothoracic and Vascular Anesthesia. The authors thank the editor in chief, Dr Kaplan, and the editorial board for the opportunity to continue this series, namely, the research highlights of the past year in the specialty of cardiothoracic and vascular anesthesiology.1 The major themes selected for 2024 are outlined in this introduction, and each highlight is reviewed in detail in the main article. The literature highlights in the specialty for 2024 begin with an update on perioperative rehabilitation and enhanced recovery in cardiothoracic surgery, with a focus on novel methods to best assess our patients in the preoperative period and the impact of implementing enhanced recovery care models on outcomes. The second major theme is focused on cardiac surgery, with the authors discussing new insights into anemia, transfusions, and coronary artery bypass grafting outcomes with a focus on gender disparities. The third theme is focused on cardiothoracic transplantation, with discussions focusing on techniques related to lung transplantation, including mechanical circulatory support. The 4th theme is focused on mechanical circulatory support, with discussions exploring advancements in left ventricular assist devices highlight the evolving landscape of mechanical circulatory support and discussion of anticoagulation practices. The fifth and final theme is an update on medical cardiology, with a focus on the outcomes of transcatheter management of regurgitant pathology, device management in heart failure, and new techniques in catheter ablation. The themes selected for this article are only a few of the diverse advances in the specialty during 2024. These highlights will inform the reader of key updates on a variety of topics, leading to improvement in perioperative outcomes for patients with cardiothoracic and vascular disease.

Incidence and risk factors of acute kidney injury in redo cardiac surgery: a single center analysis

The incidence, risk factors and prognostic implications of acute kidney injury (AKI) in patients undergoing redo cardiac surgery are still poorly defined. We prospectively collected data on 394 consecutive redo patients between January 2011 and October 2020. Patients were divided into groups according to the occurrence of different degrees of postoperative AKI (No AKI vs. Any AKI; No AKI-AKI 1 vs. AKI 2-3). The relationship between AKI and other major complications was also investigated. Postoperatively, AKI 1 occurred in 124 (31.5%), AKI 2 in 36 (9.1%) and AKI 3 in 64 (16.2%). Higher KDIGO classes were associated with increased in-hospital mortality: 5.3% among patients with no postoperative AKI and 8.9%, 13.9% and 64.1% in patients with AKI 1, 2 and 3, respectively (p < 0.001). Age, baseline hemoglobin, comorbidity, EuroSCORE II, operative time and transfusion during CPB proved to be significantly associated to the occurrence of AKI. Our study confirms the burden and prognostic role of AKI in a large, all comers, single center database of redo cardiac procedures.

Iron Treatment in Patients with Iron Deficiency Before and After Metabolic and Bariatric Surgery: A Narrative Review

Iron is an essential nutrient in living organisms with multiple vital functions. Iron deficiency (ID) can cause long term health consequences beyond iron deficiency anemia (IDA). The high prevalence of ID and its long-term effects in patients with obesity and after metabolic and bariatric surgery (MBS) is recognized. Nevertheless, there is limited knowledge of the optimal route or dose for treatment of patients with obesity and post-MBS, and an evidence-based universal guideline for prevention and treatment of ID in short- and long-term post-MBS (PMBS) is not yet available. ID in the general population is currently treated with oral or parenteral iron, where oral iron treatment is considered the preferred option with parenteral iron as a second-line treatment in case there is intolerance or lack of response to oral iron. In patients with obesity with chronic low-grade inflammation and PMBS patients with altered gut anatomy and function, there are also alterations in the bioavailability and higher risks of side effects of available oral irons. The conclusions of current studies exploring effective treatment of iron deficiency in this population have been inconsistent and further well-planned randomized and prospective studies are needed. This is a narrative review of the literature on the available treatment options and strategies for treatment of ID in PMBS patients to recognize the knowledge gaps and provides topics of future research.

Optimizing Safety and Success: The Advantages of Bloodless Cardiac Surgery. A Systematic Review and Meta-Analysis of Outcomes in Jehovah's Witnesses

Transfusions are extremely frequent after cardiac surgery, and they have a considerable economic burden and impact on outcomes. Optimal patient blood management could play a fundamental role in reducing the rate of transfusion and Jehovah's Witnesses (JW) represent the ideal surrogate study population. This meta-analysis compares outcomes of JWs and non-JWs' patients undergoing cardiac surgery, assessing the safety of a bloodless cardiac surgery. A scoping review was conducted using a search strategy for studies assessing outcomes of JW undergoing cardiac surgery. The primary outcome was perioperative mortality, and a random-effects meta-analysis was performed. Ten studies were included in our meta-analysis, involving 780 JW patients refusing any type of transfusion ("JW") and 1182 patients accepting transfusion if needed ("non-JW"). 86% of non-JW patients received at least 1 transfusion. There was no significant difference in terms of perioperative mortality (OR 0.91; 95% CI 0.55-1.52; p = 0.72). The volume blood loss was significantly less in the JW (p = 0.001), while the rate of reoperation for bleeding was also lower, but not statistically significative, in the JW (p = 0.16). Both preoperative and postoperative hemoglobin and hematocrit were significantly higher in the JW. Therefore, we concluded that bloodless cardiac surgery is safe and early outcomes are similar between JW and non-JW patients: optimal patient blood management is fundamental in guarantying these results. Further studies are needed to assess if a limitation of transfusion could have a positive long-term impact on outcomes.

[Iron deficiency in cardiac surgery patients and the possibility of its correction at the preoperative stage]

Among cardio-surgical patients, the prevalence of iron deficiency conditions reaches 70 %, and anemia is detected in less than 50% cases. Meanwhile, both anemia and latent iron deficiency are risk factors for adverse outcomes in cardio-surgical patients. These conditions are associated with a high frequency and greater volume of blood transfusions as well as with a longer stay in the hospital. Timely diagnosis and correction of iron deficiency, regardless of the presence of anemia, are mandatory at the stage of preoperative preparation. The use of oral iron medicines is limited by their low efficacy in this category of patients and a high risk of adverse events. Intravenous iron medicines have a high potential for correcting iron deficiency, and their efficacy and safety have been previously demonstrated. Administration of ferric carboxymaltose has proved beneficial in studies on iron deficiency correction in cardiological and cardio-surgical patients. In these patients, ferric carboxymaltose improved the dynamics of ferritin and hemoglobin, reduced the risk of blood transfusion, and decreased the duration of stay in the hospital. Preoperative intravenous administration of ferric carboxymaltose to cardio-surgical patients can improve clinical outcomes and the cost effectiveness of cardiac surgery.

How Important Impact of Low Level of Hematocrit Can Be on Outcome in Patients Undergoing Off Pump Coronary Artery Bypass Surgery?

Background

Cardiosurgical patients can be often anemic, and preoperative anaemia is associated with increased postoperative complications, as well as morbidity and mortality.

Objective

The present study was conducted aiming to determine the influence of lower preoperative hematocrit values on the early postoperative recovery of patients undergoing elective off-pump coronary artery bypass grafting (OPCABG).

Methods

Our retrospective study included 150 patients who underwent elective OPCABG surgery from September 2021 to December 2022 at the Clinic for Cardiovascular Surgery University of Sarajevo. Patients were divided into two groups, anemic and non-anemic, with anemia defined as hemoglobin level <130g/l males and <120g/l females. Study observed comorbidities and early postoperative data.

Results

Overall prevalence of anemia in OPCABG patients was 36,6%, more frequent among older patients. Comorbidities as chronic obstructive pulmonary disease, hypertension, ejection fraction was quite similar in both groups, but body mass index was significantly higher in the group of patients with anemia (29.9% vs 28.4%). In early recovery period, vasopressors were more used in patients with anemia (63.6% vs 42.1%) and their doses were higher. Total drainage was higher in patients with anemia (744.45±45.72 ml vs 681.58±349.06 ml). Number of transfusions was higher in the group of patients with anemia: red blood cells (0.89±1.29 vs 0.29±0.84; p<0,05), fresh frozen plasma (0.65±1.13 vs 0.41±1.15; p<0,05) and platelets (0.11±0.57 vs 0,07±0.42; p>0,05). Duration of mechanical ventilation was longer in patients with anemia compared to non-anemic patients (623-91±259.83 minutes vs 469±191.13 minutes). Atrial fibrillation occurred more often in patients with anemia (12.7 vs 7.4%). Length of stay in the intensive care unit was without significant difference.

Conclusion

Based on our findings, patients who underwent elective OPCABG with lower than normal hematocrit, needed more blood and blood products, more vasopressor drugs in higher doses, longer mechanical ventilation, all which can prolong the patient's recovery and increase the cost of treatment.

Prognostic Implication of Preoperative Anemia in Redo Cardiac Surgery: A Single-Center Propensity-Matched Analysis

Preoperative anemia has been associated with increased morbidity and mortality after cardiac surgery, but little is known about its prognostic value in the setting of redo procedure. A retrospective, observational cohort study of prospectively collected data was undertaken on 409 consecutive patients referred for redo cardiac procedures between January 2011 and December 2020. The EuroSCORE II calculated an average mortality risk of 25.7 ± 15.4%. Selection bias was assessed with the propensity-adjustment method. The prevalence of preoperative anemia was 41%. In unmatched analysis, significant differences between the anemic and nonanemic groups emerged in the risk for postoperative stroke (0.6% vs. 4.4%, p = 0.023), postoperative renal dysfunction (29.7% vs. 15.6%, p = 0.001), a need for prolonged ventilation (18.1% vs. 7.2%, p = 0.002), and high-dosage inotropes (53.1% vs. 32.9%, p < 0.001) along with both length of ICU and hospital stay (8.2 ± 15.9 vs. 4.3 ± 5.4 days, p = 0.003 and 18.8 ± 17.4 vs. 14.9 ± 11.1, p = 0.012). After propensity matching (145 pairs), preoperative anemia was still significantly associated with postoperative renal dysfunction, stroke, and the need for high-dosage inotrope cardiac morbidity. Preoperative anemia is significantly associated with acute kidney injury, stroke, and the need for high-dosage inotropes in patients referred for redo procedures.