Evidence-Based Medicine: Principles and Values as Illustrated by the Case of Patient Blood Management.

Evidence-based medicine is considered 1 of the 15 great inventions in medicine. It aims to remove bias in medical decision-making as much as possible through a rigorous process. In this article, the principles of evidence-based medicine are illustrated using the case of patient blood management (PBM). Acute or chronic bleeding, iron deficiency, and renal and oncological diseases may lead to preoperative anemia. To compensate for severe and life-threatening blood loss during surgery, doctors transfuse red blood cells (RBCs). PBM is an approach to take care of patients at risk for anemia, which includes detecting and treating anemia before surgery. Alternative interventions to treat preoperative anemia are the use of iron supplementation with or without erythro-stimulating agents (ESAs). The best available scientific evidence today indicates that preoperative intravenous (IV) or oral iron monotherapy may not be effective to reduce RBC utilization (low-certainty evidence). Preoperative IV iron supplementation in addition to ESAs is probably effective to reduce RBC utilization (moderate-certainty evidence), whereas oral iron supplementation in addition to ESAs may be effective to reduce RBC utilization (low-certainty evidence). The adverse events of preoperative oral/IV iron and/or ESAs and their impact on patient-important outcomes (morbidity, mortality, quality of life) remain unclear (very low-certainty evidence). Since PBM is a patient-centered approach, emphasis on monitoring and evaluation of patient-important outcomes in future research is urgently needed. Finally, the cost-effectiveness of preoperative oral/IV iron monotherapy is unproven, whereas preoperative oral/IV iron in addition to ESAs is extremely cost-ineffective.

Adverse events of iron and/or erythropoiesis-stimulating agent therapy in preoperatively anemic elective surgery patients: a systematic review.

BACKGROUND: Iron supplementation and erythropoiesis-stimulating agent (ESA) administration represent the hallmark therapies in preoperative anemia treatment, as reflected in a set of evidence-based treatment recommendations made during the 2018 International Consensus Conference on Patient Blood Management. However, little is known about the safety of these therapies. This systematic review investigated the occurrence of adverse events (AEs) during or after treatment with iron and/or ESAs. METHODS: Five databases (The Cochrane Library, MEDLINE, Embase, Transfusion Evidence Library, Web of Science) and two trial registries (ClinicalTrials.gov, WHO ICTRP) were searched until 23 May 2022. Randomized controlled trials (RCTs), cohort, and case-control studies investigating any AE during or after iron and/or ESA administration in adult elective surgery patients with preoperative anemia were eligible for inclusion and judged using the Cochrane Risk of Bias tools. The GRADE approach was used to assess the overall certainty of evidence. RESULTS: Data from 26 RCTs and 16 cohort studies involving a total of 6062 patients were extracted, on 6 treatment comparisons: (1) intravenous (IV) versus oral iron, (2) IV iron versus usual care/no iron, (3) IV ferric carboxymaltose versus IV iron sucrose, (4) ESA+iron versus control (placebo and/or iron, no treatment), (5) ESA+IV iron versus ESA+oral iron, and (6) ESA+IV iron versus ESA+IV iron (different ESA dosing regimens). Most AE data concerned mortality/survival (n=24 studies), thromboembolic (n=22), infectious (n=20), cardiovascular (n=19) and gastrointestinal (n=14) AEs. Very low certainty evidence was assigned to all but one outcome category. This uncertainty results from both the low quantity and quality of AE data due to the high risk of bias caused by limitations in the study design, data collection, and reporting. CONCLUSIONS: It remains unclear if ESA and/or iron therapy is associated with AEs in preoperatively anemic elective surgery patients. Future trial investigators should pay more attention to the systematic collection, measurement, documentation, and reporting of AE data.

Effectiveness of Iron Supplementation With or Without Erythropoiesis-Stimulating Agents on Red Blood Cell Utilization in Patients With Preoperative Anaemia Undergoing Elective Surgery: A Systematic Review and Meta-Analysis.

Patient Blood Management (PBM) is an evidence-based, multidisciplinary, patient-centred approach to optimizing the care of patients who might need a blood transfusion. This systematic review aimed to collect the best available evidence on the effectiveness of preoperative iron supplementation with or without erythropoiesis-stimulating agents (ESAs) on red blood cell (RBC) utilization in all-cause anaemic patients scheduled for elective surgery. Five databases and two trial registries were screened. Primary outcomes were the number of patients and the number of RBC units transfused. Effect estimates were synthesized by conducting meta-analyses. GRADE (Grades of Recommendation, Assessment, Development and Evaluation) was used to assess the certainty of evidence. We identified 29 randomized controlled trials (RCTs) and 2 non-RCTs comparing the effectiveness of preoperative iron monotherapy, or iron + ESAs, to control (no treatment, usual care, placebo). We found that: (1) IV and/or oral iron monotherapy may not result in a reduced number of units transfused and IV iron may not reduce the number of patients transfused (low-certainty evidence); (2) uncertainty exists whether the administration route of iron therapy (IV vs oral) differentially affects RBC utilization (very low-certainty evidence); (3) IV ferric carboxymaltose monotherapy may not result in a different number of patients transfused compared to IV iron sucrose monotherapy (low-certainty evidence); (4) oral iron + ESAs probably results in a reduced number of patients transfused and number of units transfused (moderate-certainty evidence); (5) IV iron + ESAs may result in a reduced number of patients transfused (low-certainty evidence); (6) oral and/or IV iron + ESAs probably results in a reduced number of RBC units transfused in transfused patients (moderate-certainty evidence); (7) uncertainty exists about the effect of oral and/or IV iron + ESAs on the number of patients requiring transfusion of multiple units (very low-certainty evidence). Effect estimates of different haematological parameters and length of stay were synthesized as secondary outcomes. In conclusion, in patients with anaemia of any cause scheduled for elective surgery, the preoperative administration of iron monotherapy may not result in a reduced number of patients or units transfused (low-certainty evidence). Iron supplementation in addition to ESAs probably results in a reduced RBC utilization (moderate-certainty evidence).

Is there a risk of transfusion-transmissible infections after percutaneous needle treatments in blood donors? A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: The donor medical questionnaire identifies a blood donor's history of known blood safety risks. Current Australian, Canadian, European and USA legislation temporarily defers blood donors who received different percutaneous needle treatments (i.e. tattooing, acupuncture and piercing) from blood donation. This systematic review aimed to scientifically underpin these deferrals by identifying the best available evidence on the association between percutaneous needle treatments and the risk of transfusion-transmissible infections (TTIs). MATERIALS AND METHODS: Studies from three databases investigating the link between percutaneous needle treatments and TTIs (HBV, HCV and HIV infection) in blood donors were retained and assessed on eligibility by two reviewers independently. The association between percutaneous needle treatments and TTIs was expressed by conducting meta-analyses and calculating pooled effect measures (odds ratios (ORs) and 95% CIs). The GRADE methodology (Grades of Recommendation, Assessment, Development and Evaluation) was used to assess the quality of evidence. RESULTS: We identified 1242 references and finally included 21 observational studies. Twenty studies assessed the link between percutaneous needle treatments and HCV infection and found that blood donors receiving these treatments had an increased risk of HCV infection (tattooing: pooled OR 5·28, 95% CI [4·33, 6·44], P < 0·00001 (low-quality evidence); acupuncture: pooled OR 1·56, 95% CI [1·17, 2·08], P = 0·03 (very low-quality evidence); and piercing: pooled OR 3·25, 95% CI [1·68, 6·30], P = 0·0005 (low-quality evidence)). CONCLUSION: Percutaneous needle treatments may be associated with an increased HCV infection risk. Further high-quality studies are required to formulate stronger evidence-based recommendations on percutaneous needle treatments as a blood donor deferral criterion.

Effect of "add-on" interventions on exercise training in individuals with COPD: a systematic review.

The aim of this review was to identify the effectiveness of therapies added on to conventional exercise training to maximise exercise capacity in patients with chronic obstructive pulmonary disease (COPD). Electronic databases were searched, identifying trials comparing exercise training with exercise training plus "add-on" therapy. Outcomes included peak oxygen uptake (V'O2peak), work rate and incremental/endurance cycle and field walking tests. Individual trial effects on exercise capacity were extracted and collated into eight subgroups and pooled for meta-analysis. Sensitivity analyses were conducted to explore the stability of effect estimates across studies employing patient-centred designs and those deemed to be of "high" quality (PEDro score >5 out of 10). 74 studies (2506 subjects) met review inclusion criteria. Interventions spanned a broad scope of clinical practice and were most commonly evaluated via the 6-min walking distance and V'O2peak. Meta-analysis revealed few clinically relevant and statistically significant benefits of "add-on" therapies on exercise performance compared with exercise training. Benefits favouring "add-on" therapies were observed across six different interventions (additional exercise training, noninvasive ventilation, bronchodilator therapy, growth hormone, vitamin D and nutritional supplementation). The sensitivity analyses included considerably fewer studies, but revealed minimal differences to the primary analysis. The lack of systematic benefits of "add-on" interventions is a probable reflection of methodological limitations, such as "one size fits all" eligibility criteria, that are inherent in many of the included studies of "add-on" therapies. Future clarification regarding the exact value of such therapies may only arise from adequately powered, multicentre clinical trials of tailored interventions for carefully selected COPD patient subgroups defined according to distinct clinical phenotypes.

Vitamin D supplementation during rehabilitation in COPD: a secondary analysis of a randomized trial.

RATIONALE: Pulmonary rehabilitation is an important treatment for patients with Chronic Obstructive Pulmonary Disease, who are often vitamin D deficient. As vitamin D status is linked to skeletal muscle function, we aimed to explore if high dose vitamin D supplementation can improve the outcomes of rehabilitation in Chronic Obstructive Pulmonary Disease. MATERIAL AND METHODS: This study is a post-hoc subgroup analysis of a larger randomized trial comparing a monthly dose of 100.000 IU of vitamin D with placebo to reduce exacerbations. 50 Subjects who followed a rehabilitation program during the trial are included in this analysis. We report changes from baseline in muscle strength and exercise performance between both study arms after 3 months of rehabilitation. RESULTS: Vitamin D intervention resulted in significantly higher median vitamin D levels compared to placebo (51 [44-62] ng/ml vs 15 [13-30] ng/ml; p < 0.001). Patients receiving vitamin D had significantly larger improvements in inspiratory muscle strength (-11±12 cmH2O vs 0±14 cmH2O; p = 0.004) and maximal oxygen uptake (110±211 ml/min vs -20±187 ml/min; p = 0.029). Improvements in quadriceps strength (15±16 Nm) or six minutes walking distance (40±55 meter) were not significantly different from the effects in the placebo group (7±19 Nm and 11±74 meter; p>0.050). CONCLUSION: High dose vitamin D supplementation during rehabilitation may have mild additional benefits to training.