The Effect of Preoperative Hematocrit Level on Early Outcomes After Coronary Artery Bypass Surgery

A Comparison of the Clinical Outcomes of Minimum and Maximum Hematocrit Levels During Cardiopulmonary Bypass (CPB) in Low-risk Patients Undergoing Coronary Artery Bypass Graft Surgery (CABG): A Cross-sectional Study

Background

This study investigated the clinical outcomes at the minimum and maximum levels of hematocrit (HCT) during cardiopulmonary bypass (CPB) in low-risk patients undergoing coronary artery bypass graft (CABG) surgery.

Materials and Methods

In this cross-sectional study, 85 patients who underwent CABG with an ejection fraction of greater than 35% were selected. Based on the HCT range during CPB, patients were divided into two groups: minimum HCT: HCT = 16-18% and maximum HCT: HCT = 25-27%. Then the operation outcomes, amount of drainage, and transfusion were recorded and compared between these groups.

Results

In the middle tube 8 h after surgery and left tube 24 h after surgery, the amount of drainage in the minimum HCT group with mean of 71.00 ± 130.9 and 60.65 ± 71.23, respectively, was significantly lower than the maximum HCT group with mean of 101.5 ± 246.50 and 123.76 ± 93.17, respectively (P value < 0.05). The incidence of cognitive disorders in the maximum HCT group was significantly higher than in the minimum HCT group (11.1% vs. 0%, P value = 0.041). Also, the mean transfusion of packed red blood cell (PRBC) and fresh frozen plasm (FFP) during CPB in the maximum HCT group, with mean of 346.7 ± 86.22 and 396.1 ± 21.05, respectively, were significantly higher than the minimum HCT group with mean of 178.8 ± 80.91 and 136.8 ± 46.77, respectively (P value < 0.05). After CPB, there was no significant difference in transfusion products (P value > 0.05).

Conclusion

According to the results of this study, patients undergoing CABG surgery with maximum HCT level versus minimum HCT level during CPB, need more packed cells and fresh frozen plasma products transfusion, which will be associated with the complication of cognitive impairment.

The association between preoperative anemia, blood transfusion need, and postoperative complications in adult cardiac surgery, a single center contemporary experience

BACKGROUND

The impact of preoperative anemia on postcardiac surgery outcomes is an area of great debate. Although several large-scale studies have been conducted, they have demonstrated conflicting results. A limited number of studies have been conducted in the Middle East. The primary aim of this study was to investigate the association between preoperative anemia and the need for blood transfusions, as well as major postoperative complications.

METHODS

Adult patients who underwent cardiac surgery at King Faisal Cardiac Center in Jeddah between June 2016 and January 2020 were included in this retrospective cohort study. The study excluded patients with hereditary preoperative anemia. Among the variables studied were variables related to demographics, comorbidities, laboratory data, operation-related data, in-hospital complications, and mortality.

RESULTS

The mean preoperative hemoglobin (Hb) level was 13.2 g/dL (SD ± 1.8). The overall mortality rate was 4.6%. A lower preoperative Hb level (p value = 0.016), postoperative day 1 WBC count (p-value = 0.003), and prolonged cross clamp time (p value < 0.001) were significantly associated with mortality. A lower Hb level during the preoperative period or within the first three days of surgery was associated with a higher blood transfusion requirement. However, there was no significant association between blood transfusion and postoperative complications. A multivariate stepwise logistic regression model was developed and several pre and intra operative factors were predictive of the need PRBCs transfusion after cardiac surgery (which included: older age, female gender, lower pre-operative hemoglobin and longer cardio-pulmonary bypass time), with had a predictive accuracy of around ~ 86%.

CONCLUSION

Based on our single center study, patients with preoperative lower Hb levels are at higher risk of mortality. However, blood transfusion does not seem to increase the risk of postoperative complications. Optimal utilization of blood products is an important quality metric and identification of patients at higher risk of requiring PRBCs transfusion prior to cardiac surgery can help in implementing pre or intra operative strategies to minimize the need for transfusion.

Predictive Value of HATCH Scoring and Waist-to-Height Ratio in Atrial Fibrillation Following Coronary Artery Bypass Operations Performed with Cardiopulmonary Bypass

Objectives

Postoperative atrial fibrillation (PoAF), an important clinical condition that can occur after coronary artery bypass graft (CABG) operations, may bring about cerebrovascular risks, prolong hospital stay and increase treatment costs. In this prospective study, we aimed to investigate the predictive value of HATCH score and waist/height ratio (WHR) values in revealing the development of PoAF after CABG operations.

Methods

Patients who underwent isolated CABG surgery with cardiopulmonary bypass between May 2019 and November 2019 were prospectively included in the study. Preoperative demographic characteristics, laboratory parameters, and operative parameters of the patients were recorded prospectively.

Results

A total of 255 patients were included in the study. Those who did not develop PoAF were included in Group 1 (N = 196, mean age = 58.9 ± 9.4 years), and those who did were included in Group 2 (n = 59, mean age = 61.1 ± 12 years). There were no statistically significant differences between the two groups in terms of age, gender, presence of hypertension and hyperlipidemia. Rates of chronic obstructive pulmonary disease and previous percutaneous coronary interventions, waist circumference, waist to height ratio and HATCH score values were significantly higher in Group 2 compared to Group 1 ( p values: 0.019, 0.034, 0.001, <0.001, <0.001, respectively). In multivariate analysis, WHR (Odds ratio: 1.068, Confidence interval: 1.032–1.105, p < 0.001) and HATCH score (Odds ratio: 2.590, Confidence interval: 1.850–3.625, p < 0.001) were independent predictors of PoAF.

Conclusions

With this current prospective study, we showed that calculating WHR and HATCH score in the preoperative period can help us predict PoAF.

The Effect of Preoperative Hematocrit Levels on Early Outcomes After Coronary Artery Bypass Graft

Introduction

Coronary artery bypass graft (CABG) is the most potent of surgical procedures; in this procedure, the narrowing of the coronary artery due to atherosclerotic plaque is bypassed by forming an alternate route for blood flow to the heart. There are various risk factors associated with the procedure. The aim of this study was to observe if postoperative outcomes are affected by preoperative hematocrit (hct) levels in patients.

Methods 

This longitudinal study was conducted from April 2019 to December 2019. Eighty-two (82) participants who were to undergo CABG surgery were divided into two groups based on their preoperative hct levels. Group 1 had 42 participants with lower levels of hct (less than 35.5% for women and 38.3% for men), whereas group 2 consisted of 40 participants with normal hct levels (greater than 35.5% for women and 38.3% for men).

Results

The results showed that participants undergoing CABG with lower than normal hct levels had increased blood loss through drainage as compared to participants who had normal hct levels (680.1 ± 301 mL vs. 500.7 ± 412 mL; p-value: 0.02). Group 1 participants also had an increased need for blood and blood product transfusion as compared to group 2 (3.2 ± 1.8 units vs. 1.8 ± 0.9 units; p-value: <0.0001). Furthermore, the participants in group 1 had longer stays in the ICU relative to the other group (5.2 ± 3.1 days vs. 3.4 ± 2.5 days; p-value: 0.003).

Conclusion

Based on our findings, patients who undergo CABG surgery with lower than normal hct levels are at increased risk of certain complications, including excessive blood loss, need for transfusion, and increased duration of ICU stay. Therefore, preoperative hct levels should be routinely checked in patients undergoing CABG to prevent these complications.