Current concepts in the evaluation and management of preoperative anemia

Reported outcomes in patients with iron deficiency or iron deficiency anemia undergoing major surgery: a systematic review of outcomes

BACKGROUND

Iron deficiency (ID) is the leading cause of anemia worldwide. The prevalence of preoperative ID ranges from 23 to 33%. Preoperative anemia is associated with worse outcomes, making it important to diagnose and treat ID before elective surgery. Several studies indicated the effectiveness of intravenous iron supplementation in iron deficiency with or without anemia (ID(A)). However, it remains challenging to establish reliable evidence due to heterogeneity in utilized study outcomes. The development of a core outcome set (COS) can help to reduce this heterogeneity by proposing a minimal set of meaningful and standardized outcomes. The aim of our systematic review was to identify and assess outcomes reported in randomized controlled trials (RCTs) and observational studies investigating iron supplementation in iron-deficient patients with or without anemia.

METHODS

We searched MEDLINE, CENTRAL, and ClinicalTrials.gov systematically from 2000 to April 1, 2022. RCTs and observational studies investigating iron supplementation in patients with a preoperative diagnosis of ID(A), were included. Study characteristics and reported outcomes were extracted. Outcomes were categorized according to an established outcome taxonomy. Quality of outcome reporting was assessed with a pre-specified tool. Reported clinically relevant differences for sample size calculation were extracted.

RESULTS

Out of 2898 records, 346 underwent full-text screening and 13 studies (five RCTs, eight observational studies) with sufficient diagnostic inclusion criteria for iron deficiency with or without anemia (ID(A)) were eligible. It is noteworthy to mention that 49 studies were excluded due to no confirmed diagnosis of ID(A). Overall, 111 outcomes were structured into five core areas including nine domains. Most studies (92%) reported outcomes within the 'blood and lymphatic system' domain, followed by "adverse event" (77%) and "need for further resources" (77%). All of the latter reported on the need for blood transfusion. Reported outcomes were heterogeneous in measures and timing. Merely, two (33%) of six prospective studies were registered prospectively of which one (17%) showed no signs of selective outcome reporting.

CONCLUSION

This systematic review comprehensively depicts the heterogeneity of reported outcomes in studies investigating iron supplementation in ID(A) patients regarding exact definitions and timing. Our analysis provides a systematic base for consenting to a minimal COS.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020214247.

Preoperative Hemoglobin <10 g/DL Predicts an Increase in Major Adverse Cardiac Events in Patients With Hip Fracture Over 80 Years: A Retrospective Cohort Study

Background

Preoperative anemia has been associated with perioperative morbidity and mortality in patients undergoing cardiac and non-cardiac surgery. Preoperative anemia is common in elderly hip fracture patients. The primary objective of the study was to explore the relationship between preoperative hemoglobin levels and postoperative major adverse cardiovascular events (MACEs) in hip fracture patients over 80 years.

Methods

The retrospective study enrolled hip fracture patients over 80 years from January 2015 to December 2021 in our center. The data were collected from the hospital's electronic database after approval by the ethics committee. The primary objective of the study was to investigate MACEs, and the secondary objectives included in-hospital mortality, delirium, acute renal failure, ICU admission rate, and transfusion (>2 U).

Results

912 patients were entered for final analysis. Based on the restricted cubic spline, the risk of preoperative hemoglobin (<10 g/DL) was associated with an increased risk of postoperative complications. With univariable logistic analysis, a hemoglobin level <10 g/DL was associated with increased MACEs [OR 1.769, 95% CI (1.074, 2.914), P = .025], in-hospital mortality [OR 2.709, 95% CI (1.215, 6.039), P = .015] and transfusion >2 U risk [OR 2.049, 95% CI (1.56, 2.69), P < .001]. Even after adjustment for confounding factors, MACEs [OR 1.790, 95% CI (1.073, 2.985), P = .026], in-hospital mortality [OR 2.81, 95% CI (1.214, 6.514), P = .016] and transfusion >2 U rate [OR 2.002, 95% CI (1.516, 2.65), P < .001] were still higher in the lower hemoglobin level cohort. Moreover, a log-rank test showed increased in-hospital mortality in the cohort with a preoperative hemoglobin level of <10 g/DL. However, there was no difference in delirium, acute renal failure, and ICU admission rates.

Conclusions

In conclusion, for hip fracture patients over 80 years, preoperative hemoglobin levels <10 g/DL might be associated with increased postoperative MACEs, in-hospital mortality, and transfusion >2 U.

Results from a type two hybrid-effectiveness study to implement a preoperative anemia and iron deficiency screening, evaluation, and management pathway

BACKGROUND

Implementation of pathways to screen surgical patients for preoperative anemia and iron deficiency remains limited. This study sought to measure the impact of a theoretically informed, bespoke change package on improving the uptake of a Preoperative Anemia and Iron Deficiency Screening, Evaluation, and Management Pathway.

STUDY DESIGN AND METHODS

Pre-post interventional study using a type two hybrid-effectiveness design evaluated implementation. Four hundred (400) patient medical record reviews provided the dataset (200 pre- and 200-post implementation). The primary outcome measure was compliance with the pathway. Secondary outcome measures (clinical outcomes) were anemia on day of surgery, exposure to a red blood cell (RBC) transfusion, and hospital length of stay. Validated surveys facilitated data collection of implementation measures. Propensity score-adjusted analyses determined the effect of the intervention on clinical outcomes, and a cost analysis determined the economic impact.

RESULTS

For the primary outcome, compliance improved significantly post-implementation (Odds Ratio 10.6 [95% CI 4.4-25.5] p < .000). In secondary outcomes, adjusted analyses point estimates showed clinical outcomes were slightly improved for anemia on day of surgery (Odds Ratio 0.792 [95% CI 0.5-1.3] p = .32), RBC transfusion (Odds Ratio 0.86 [95% CI 0.41-1.78] p = .69) and hospital length of stay (Hazard Ratio 0.96 [95% CI 0.77-1.18] p = .67), although these were not statistically significant. Cost savings of $13,340 per patient were realized. Implementation outcomes were favorable for acceptability, appropriateness, and feasibility.

CONCLUSION

The change package significantly improved compliance. The absence of a statistically significant change in clinical outcomes may be because the study was powered to detect an improvement in compliance only. Further prospective studies with larger samples are needed. Cost savings of $13,340 per patient were achieved and the change package was viewed favorably.

Current concepts in evaluation and management of preoperative anaemia in patients undergoing thoracic surgery

PURPOSE OF REVIEW

The purpose of this review is to evaluate the current recommendations for management of perioperative anaemia in patients undergoing thoracic surgery, present the impact of anaemia on outcomes in this patient population and suggest an algorithm for evaluating and treating anaemia preoperatively.

RECENT FINDINGS

Anaemia is a common medical issue noted preoperatively in patients presenting for thoracic surgery and carries significant morbidity. Preoperative anaemia increases the likelihood of receiving a perioperative transfusion, which represents a significant risk factor for morbidity and reduced disease-free survival in lung cancer patients presenting for thoracic surgery. It is also associated with longer hospital lengths of stay and increased risk for reoperation following lung transplantation. An algorithm-based approach to management of anaemia is beneficial and treatment with iron has been shown to reduce transfusions.

SUMMARY

Patients undergoing thoracic surgery have a high incidence of preoperative anaemia that increases the risk of transfusion and postoperative morbidity. Preoperative evaluation and tailored treatment based on the underlying cause of anaemia reduces the incidence of anaemia prior to surgery and decreases transfusion rates.

A portable smartphone-based hemoglobin point-of-care testing platform for accurate anemia diagnostics

Anemia affects over 2 billion people worldwide, with the heaviest burden borne by women and children. At present, anemia is diagnosed by measuring hemoglobin (Hb) levels, which must be done in hospitals or commercial laboratories by skilled operators. In this work, we report a portable, affordable ($3), easy-to-operate (1 min) and accurate smartphone-based Hb analyzer (SHbA) that uses a drop of finger-pricked blood for anemia point-of-care test (POCT) applications. POCT of Hb was achieved using a smartphone ambient light sensor (ALS) to accurately measure the absorbance of colorimetric Hb biochemical analysis reagents in a microcuvette, as well as an Android-based application for results analysis. SHbA validation results agreed well with those reported by a hematology analyzer, and the SHbA has an anemia diagnosis sensitivity of 95.4% and specificity of 96.3% for venous blood (n = 360) and a sensitivity of 96.39% and specificity of 95.58% for fingertip blood (n = 475). In addition, SHbA exhibits excellent performance in the diagnosis and treatment guidance of anemia high-risk populations, including tumor chemotherapy patients (n = 424), pregnant women (n = 214) and thalassemia patients (n = 208). Importantly, volunteer self-testing results (n = 20) indicate that SHbA can be used for home-based anemia diagnosis and monitoring. SHbA has the advantages of high sensitivity and specificity while being cheap and easy to operate, making it widely applicable for the diagnosis and treatment of anemia, especially for high-risk patients in areas with poor medical resources.

Addressing comorbidities in the perioperative setting and optimizing perioperative medicine education

PURPOSE OF REVIEW

Preoperative clinics and patient optimization are examples of collaborative, multidisciplinary care pathways that create value. This article reviews current literature to demonstrate the importance of preoperative enhancement of patients' cognitive and functional status. This article underscores the importance of formal training in multidisciplinary topics, such as frailty, brain health, and shared decision-making for anesthesiology house staff.

RECENT FINDINGS

Preoperative cognitive screening of older patients is a valuable metric for risk stratification and detection of patients at risk of postoperative delirium. Frailty is another syndrome that can be identified and optimized preoperatively. Sarcopenia has been shown to correlate with frailty; this shows promise as a method to detect frailty preoperatively.

SUMMARY

Anesthesiologists as perioperative physicians are in a unique position to lead and coordinate interdisciplinary conversations that incorporate patient goal concordant care and realistic assessment of perioperative complications. Formal house staff training in early recognition and management of patients at risk of adverse outcomes in the short and long term postoperatively improves patient outcomes and decreases healthcare spending.

[Peri- and Postoperative Anaemia Management]

Patient Blood Management (PBM) aims to diagnose and treat preoperative anaemia, avoid unnecessary blood loss, and enable rational use of blood products. Due to various limitations, treatment of preoperative anaemia has been successful in only a few German hospitals to date. Thus, the peri- and postoperative phase is increasingly becoming important for implementing various preventive and therapeutic measures for the treatment of (postoperative) anaemia. These will be comprehensively presented in the following.