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.

Topical rifampicin for prevention of deep sternal wound infections in patients undergoing coronary artery bypass grafting

Deep sternal wound infections (DSWI), although an infrequent complication, significantly impair postoperative outcomes after coronary artery bypass grafting (CABG) surgery. Among several preventive strategies, topical antibiotic therapy immediately before sternal closure has been strongly advocated. In this retrospective analysis, the incidence of DSWI in 517 patients undergoing isolated CABG and receiving rifampicin irrigation of mediastinum, sternum and suprasternal tissues was compared to an historical consecutive cohort of 448 patients. To account for the inherent selection bias, a 1:1 propensity matched analysis was performed. Patients receiving topical rifampicin experienced significantly less occurrence of postoperative DSWI (0.2% vs 2.5%, p = 0.0016 in the unmatched analysis; 0.3% vs 2.1%, p = 0.0391 in the matched analysis). Intensive care unit stay, hospital stay, and operative mortality were similar between groups. This study shows that topical rifampicin in combination with commonly prescribed preventative strategies significantly reduces the incidence of DSWI to less than 0.3% in unselected patients undergoing a full median sternotomy for CABG. Further studies, including a larger number of patients and with a randomization design, would establish the potential preventative role of topical rifampicin in reducing the occurrence of DSWI.

The effect of various blood management strategies on intraoperative red blood cell transfusion in first-time coronary artery bypass graft patients

Effective blood management during cardiac surgery requires a multifactorial effort to limit exposure to allogeneic blood products. The present study evaluated the distribution of intraoperative interventions in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass. Records from patients undergoing non-reoperative surgery at 120 hospitals between January 2017 and December 2017 were reviewed, and red blood cell transfusion quartiles established. The 31 hospitals with the lowest transfusion rates fell into the first quartile (low transfusion group, n = 3,186 patients), while 29 hospitals with the highest transfusion were in the fourth quartile (high transfusion group, n = 2,561). A survey was sent to assess the blood management techniques: acute normovolemic hemodilution, autologous prime, fluid management, intraoperative autotransfusion, ultrafiltration, and transfusion triggers. All data are presented as mean (standard deviation). Patients in the low transfusion group had red blood cell transfusion rate of 5.5%, while the high transfusion group was 28.3%. There was no difference in gender or age. Fluid management was reduced in the low transfusion group with smaller prime volumes and anesthesia volumes, but higher crystalloid use during cardiopulmonary bypass. The low transfusion group did not use acute normovolemic hemodilution as often and had lower sequestered volumes when used. When ultrafiltration was used, the low transfusion quartile group removed more volume (1,555.9 ± 955.2 vs. 1,326.1 ± 918.9 mL, p ⩽ 0.001). In the low transfusion group, nadir hematocrit on-cardiopulmonary bypass averaged 1.6% lower and 3.0% lower for transfusion post-cardiopulmonary bypass. Intraoperative red blood cell units averaged 0.11 ± 0.50 U in low transfusion group compared to 0.63 ± 1.14 U in the high transfusion group. Mixed-effects logistic regression identified first in operating room and first on cardiopulmonary bypass hematocrit, estimated blood volume and nadir hematocrit transfusion trigger as the strongest predictors for red blood cell transfusion. Significant variation exists in the transfusion of red blood cell in coronary artery bypass graft patients undergoing cardiopulmonary bypass which may be related to the application of intraoperative blood management techniques.

The effect of protamine dosing variation on bleeding and transfusion after heparinisation for cardiopulmonary bypass

INTRODUCTION

Accurate dosing of protamine reversal following on-pump cardiac surgical procedures is challenging, with both excessive and inadequate administration recognised to increase bleeding risk. We aimed to examine the relationship between three ratios for heparin reversal and markers of haemostasis.

METHODS

A retrospective analysis of a prospectively collected database was undertaken at a single tertiary cardiac unit, reviewing all cases of on-pump coronary artery bypass grafts and single valve replacements from 01/01/2011 to 31/12/2015. The ratio between total intra-operative heparin and protamine was stratified to three groups (low: ≤0.6 mg per 100 IU of heparin, moderate: 0.6-1.0 and high: >1.0) and related to the primary outcome of red blood cell (RBC) transfusion, with secondary outcomes being the number of units transfused, the haemoglobin differential and mediastinal drain output at 4 hours.

RESULTS

Of the 803 patients identified, 338 received a blood transfusion, with 1035 units being used. Eighteen percent of individuals (145) received a low ratio, 50% (404) received a moderate ratio and 32% (254) a high ratio. Using the moderate group as a reference, the low dose group was 56.5% less likely to have received a RBC transfusion (OR 0.435; 95% CI 0.270:0.703 p=0.001) while the high dose group carried a 241% increased association with transfusion (OR 3.412; 95% CI 2.399:4.853 p<0.001). For those transfused, a lower protamine:heparin ratio was associated with a lower number of units transfused, lesser haemoglobin differential and less mediastinal drain output.

CONCLUSION

Higher doses of intra-operative protamine relative to heparin are associated with greater risk of transfusion and post-operative bleeding.

A Difference in Bleeding and Use of Blood and Blood Products in Patients who Were Preoperatively on Aspirin or Dual Antiplatelet Therapy Before Coronary Artery Bypass Grafting

Background

Postoperative bleeding in patients who underwent elective coronary artery bypass surgery (CABG) may increase due to preoperative anticoagulant therapy indicative of their disease - acute coronary syndrome or implanted coronary artery stent. Increased bleeding in many cases requires the use of blood and blood derivatives, and sometimes even reoperation. Their use poses the risk of complications, may extend the hospitalization.

Methods

Our observation retrospective study included 131 patients, 41 treated with aspirin and 90 treated with aspirin and clopidogrel. All underwent for the first time elective on-pump isolated CABG surgery at Clinic for cardiovascular surgery of Clinical Center University of Sarajevo, in period June 2016 to September 2017. The data were collected from patient's records.

Results

Out of 131 patients,73.3% were male. The average age was 62. The average total drainage during the first 48 postoperative hours in ASA group was 1027.4±404.9ml and 1049.8±371.3ml in DAPT group. The mean number of whole blood transfusions in the DAPT group washigher compared to ASAgroup. The average number of fresh frozen plasma were higher in the DAPT group 0.84±0.51 compared to the group ASA 0.39±0.07, as well the average thrombocytes transfusions were slightly higher in the DAPT group. Statistical analysis suggests that there is no significant difference between the observed groups (p>0.05). Also, our study did not show a statistically significant difference between arrhythmia onset, the length of mechanical ventilation, use of protamineand tranexamic acid. Reoperation due to postoperative bleeding was recorded in 2 cases in the DAPT group as well as 2 lethal cases.

Conclusion

In our study, we could not demonstrate less postoperative bleeding and use of blood and blood products in a group of patients who were preoperatively treated with aspirin compared to patients with dual antiplatelet therapy in the elective isolated CABG surgery.

Age and blood transfusion: relationship and prognostic implications in cardiac surgery

Background

Red blood cell (RBC) transfusion is a well-known predictor of acute kidney injury (AKI) and death after cardiac surgery. This study aimed to define the relationship between age and the need for RBC.

Methods

Study population included 1,765 consecutive patients undergoing on-pump procedures from 2013 to 2015. The relationship between RBC transfusion and both survival and AKI, and any interaction with age was estimated. A propensity score for the likelihood to receive RBC transfusion was calculated using multivariate logistic regression analysis to adjust for the effect of confounding factors. A logistic estimation curve was developed to investigate the interaction between this score and age.

Results

Patients receiving RBC transfusions had more comorbidities irrespective of age. Elderly patients underwent transfusion more often than younger patients with a 1.3-fold increase in the relative risk for transfusion. Age did not independently predict the need for RBC. AKI and mortality rates were significantly higher in transfused subsets irrespective of age.

Conclusions

Comorbidity profile and not age per se confers an increased risk of transfusion.

Practice guidelines for perioperative blood management: an updated report by the American Society of Anesthesiologists Task Force on Perioperative Blood Management*

The American Society of Anesthesiologists Committee on Standards and Practice Parameters and the Task Force on Perioperative Blood Management presents an updated report of the Practice Guidelines for Perioperative Blood Management.

Supplemental Digital Content is available in the text.