The PREVENNT randomised, double-blind, controlled trial of preoperative intravenous iron to treat anaemia before major abdominal surgery: an independent discussion

Preoperative anemia and long-term survival in patients undergoing colorectal cancer surgery: a retrospective cohort study

BACKGROUND

The impact of preoperative anemia on a survival outcome and the importance of correcting preoperative anemia in patients with colorectal cancer (CRC) remain controversial. This study aimed to explore how preoperative anemia affects the long-term survival of patients undergoing colorectal cancer surgery.

METHODS

This was a retrospective cohort study in which adult patients underwent surgical resection for colorectal cancer between January 1, 2008, and December 31, 2014, at a large tertiary cancer center. A total of 7436 patients were enrolled in this study. Anemia was defined according to the diagnostic criteria of China (hemoglobin level < 110 g/L for women and < 120 g/L for men). The median follow-up time was 120.5 months (10.0 years). Inverse probability of treatment weighting (IPTW) using the propensity score was used to reduce selection bias. Overall survival (OS) and disease-free survival (DFS) were compared between patients with and without preoperative anemia using the Kaplan-Meier estimator and the weighted log-rank test based on IPTW. Univariate and multivariate Cox proportional hazards models were used to assess factors associated with OS and DFS. Multivariable Cox regression was also used to assess red blood cell (RBC) transfusion associations between preoperative anemia and outcomes.

RESULTS

After IPTW adjustment, clinical profiles were similar, except that tumor location and TNM stage remained imbalanced between the preoperative anemia and preoperative non-anemia groups (p < 0.001). IPTW analysis showed that the 5-year OS rate (71.3 vs. 78.6%, p < 0.001) and the 5-year DFS rate (63.9 vs. 70.9%, p < 0.001) were significantly lower in the preoperative anemia group. Multivariate analysis showed that preoperative anemia was associated with poorer OS and DFS, while RBC transfusion may improve OS (hazard ratio [HR] 0.54, p = 0.054) and DFS (HR 0.50, p = 0.020) in CRC patients with preoperative anemia.

CONCLUSIONS

Preoperative anemia is an independent risk factor for survival in patients undergoing colorectal surgery. Strategies to reduce preoperative anemia in patients with CRC should be considered.

Patient Blood Management in Transurethral Resection Surgery: Overview and Strategy Analysis from a French Tertiary Hospital

INTRODUCTION

Since Patient blood management (PBM) suggests a bundle of measures aiming to reduce perioperative blood transfusion because preoperative anemia and blood transfusion are associated with poor postoperative outcomes. There is a lack of data on the effect of PBM in patients undergoing transurethral resection of prostate (TURP) or bladder tumor (TURBT). We aimed to assess the bleeding risk in TURP and TURBT procedures and the effect of preoperative anemia on postoperative morbimortality.

METHODS

A single-center retrospective observational cohort study was conducted in a tertiary hospital in Marseille, France. All patients undergoing TURP or TURBT were included in 2020 and divided into two groups: preoperative anemia (n = 19) and no preoperative anemia (n = 59). We recorded demographic characteristics, preoperative hemoglobin concentration, iron deficiency markers, preoperative initiation of a treatment for anemia, perioperative bleeding, and postoperative outcomes up to 30 days including blood transfusion, hospital readmission, reintervention, infection, and mortality.

RESULTS

Baseline characteristics were comparable between groups. No patient had iron deficiency markers and no prescription of iron was initiated before surgery. No major bleeding was reported during surgery. Postoperative anemia was found in 21 patients, including 16 (76%) in the preoperative anemia group and 5 (24%) in the non-preoperative anemia group. One patient of each group received a blood transfusion after surgery. No significant differences in 30-day outcomes were reported.

CONCLUSION

Our study suggests that TURP and TURBT are not associated with a high-risk of postoperative bleeding. In such procedures, adherence PBM strategies do not seem beneficial. Since recent guidelines recommend restricting preoperative testing, our results may help to improve preoperative risk stratification.

Preoperative Anemia Is a Predictor of Worse Postoperative Outcomes Following Open Pancreatoduodenectomy: A Propensity Score-Based Analysis

Background

Preoperative anemia is a common clinical situation proved to be associated with severe outcomes in major surgeries, but not in pancreatic surgery. We aim to study the impact of preoperative anemia on morbidity and mortality in patients undergoing open pancreatoduodenectomy and use propensity score matching (PSM) to balance the basal data and reduce bias.

Methods

We analyzed the data of consecutive patients undergoing open pancreatoduodenectomy with a complete record of preoperative hemoglobin, at two pancreatic centers in China between 2015 and 2019. Anemia is defined as hemoglobin less than 12 g/dl for male and 11 g/dl for female, following Chinese criteria. We compared clinical and economic outcomes before and after PSM and used logistic regression analysis to assess the correlation between variables and anemia.

Results

The unmatched initial cohort consisted of 517 patients. A total of 148 cases (28.6%) were diagnosed with anemia at admission, and no case received a preoperative blood transfusion or anti-anemia therapy. After PSM, there were 126 cases in each group. The rate of severe postoperative complications was significantly higher in the anemia group than in the normal group (43.7% vs. 27.0%, p = 0.006), among which the differences in prevalence of clinically relevant postoperative pancreatic fistula (CR-POPF) (31.0% vs. 15.9%, p = 0.005) and cardiac and cerebrovascular events (4.0% vs. 0.0%, p = 0.024) were the most significant. The costs involved were more in the anemia group (26958.2 ± 21671.9 vs. 20987.7 ± 10237.9 USD, p = 0.013). Among anemic patients, receiver operating characteristic (ROC) curve analysis shows the cut-off value of hemoglobin, below which, patients are prone to suffer from major complications (104.5 g/l in male and 90.5 g/l in female). Among all patients, multivariate analysis showed that preoperative obstructive jaundice [odds ratio (OR) = 1.813, 95% confidence interval (CI) (1.206–2.725), p = 0.004] and pancreatic ductal adenocarcinoma [OR = 1.861, 95% CI (1.178–2.939), p = 0.008] were predictors of anemia. Among paired patients, preoperative anemia [OR = 2.593, 95% CI (1.481–5.541), p = 0.001] and malignant pathology [OR = 4.266, 95% CI (1.597–11.395), p = 0.004] were predictors of postoperative severe complications.

Conclusion

Preoperative anemia is a predictor of worse postoperative outcomes following open pancreatoduodenectomy and needs to be identified and treated.

Hematinic and Iron Optimization in Peri-operative Anemia and Iron Deficiency

Purpose of Review

Preoperative anemia is independently associated with worse postoperative outcomes following cardiac and noncardiac surgery. This article explores the current understanding of perioperative anemia and iron deficiency with reference to definition, diagnosis, and treatment.

Recent Findings

Iron deficiency is the most common cause of anemia. It can arise from reduced iron intake, poor absorption, or excess iron loss. Inflammation throughout the preoperative period can drive iron sequestration, leading to a functional deficiency of iron and the development of what was referred to until recently as the “anemia of chronic disease.” Current best practice guidance supports the routine administration of preoperative intravenous iron to treat anemia despite limited evidence. This “one size fits all” approach has been called into question following results from a recent large, randomized trial (the PREVENTT trial) that assessed the use of a single dose of intravenous iron compared to placebo 10–42 days before major abdominal surgery. Although there were no improvements in patient-centered outcomes apparent during the initial hospital stay, secondary endpoints of this trial suggested there may be some late benefit after discharge from the hospital (8 weeks postoperatively). This trial raises questions on (1) the mechanisms of iron deficiency in the perioperative patient; (2) the need to reassess our opinions on generic anemia management; and (3) the need to address patient outcomes after discharge from hospital.

Summary

Despite the known associations between preoperative anemia (particularly iron deficiency anemia) and poor postoperative outcome, recent evidence suggests that administering intravenous iron relatively close to surgery does not yield a tangible short-term benefit. This is made more complex by the interplay between iron and innate immunity. Iron deficiency irrespective of hemoglobin concentration may also impact postoperative outcomes. Therefore, further research into associations between iron deficiency and postoperative outcomes, and between postoperative anemia, delayed outcomes (hospital readmission), and the efficacy of postoperative intravenous iron is required.