Prevalence of and Recovery From Anemia Following Hospitalization for Critical Illness Among Adults

Predictors of Anemia Recovery in Patients with Pre-existing Anemia Undergoing Metabolic Bariatric Surgery: A Retrospective Cohort Study

BACKGROUND

Although studies have explored the development of postoperative anemia after metabolic bariatric surgery, little is known about the effect of metabolic bariatric surgery on anemia recovery in patients with pre-existing anemia. Therefore, the objective of this study was to determine the prevalence of anemia recovery six months after metabolic bariatric surgery and predictors associated with recovery.

METHODS

This was a retrospective cohort study of 1,664 patients with pre-existing anemia aged 18-80 years who received a primary metabolic bariatric procedure between January 2010 and June 2020. The primary outcome of interest was the percentage of patients who recovered from anemia as defined by the World Health Organization thresholds at six-months post-metabolic bariatric surgery.

RESULTS

Of the 1,664 patients identified with preoperative anemia, 952 (57.2%) recovered six-months post-metabolic bariatric surgery. Female sex (OR 1.93, 95% CI 1.42-2.61, p < 0.001), age between 45-54 years vs. under 35 years (OR 1.48, 95% CI 1.08-2.05, p < 0.05), and receiving sleeve gastrectomy vs. Roux-en-Y gastric bypass (OR 1.41, 95% CI 1.06-.86, p < 0.05) were associated with significantly higher odds of recovery. A preoperative hemoglobin of 11-20 g/L below normal as compared to 0-10 g/L below normal (OR 0.52, 95% CI 0.40-0.69, p < 0.001) was associated with significantly lower odds of recovering from anemia.

CONCLUSION

More than half of patients with preoperative anemia undergoing metabolic bariatric surgery recover from anemia after their procedure. Age, sex, preoperative hemoglobin, and surgery type all influence recovery. The total body weight lost after six-months post-surgery conferred no significant effect.

Utility of reticulocyte hemoglobin as a new predictor of anemia in intensive care unit patients

Introduction

Iron deficiency and anemia are common complications in critically ill patients, particularly in the Intensive Care Unit setting (ICU), where inflammation and infection are prevalent. Traditional markers like ferritin are unreliable in these contexts due to their behavior as acute-phase reactants. New hematimetric indices, such as Reticulocyte Hemoglobin Equivalent (RET-He) and Delta Hemoglobin Equivalent (Delta-He), may offer better predictive value for anemia in ICU patients.

Objectives

This study aimed to evaluate the predictive utility of RET-He and Delta-He for anemia in critically ill patients and compare their performance with serum ferritin levels.

Methods

A pilot, observational, prospective study was conducted on 40 ICU patients admitted for burns or polytrauma. Hematological and hematimetric parameters were analyzed at admission, 48 h, 4 days, and 7 days post-admission. Mixed-effects regression models were used to assess the predictive value of RET-He, Delta-He, and ferritin for hemoglobin levels and anemia.

Results

Significant reductions in hemoglobin and hematocrit were observed within the first 48 h of ICU admission, while RET-He and Delta-He remained stable. Over 4 and 7 days, decreases in RET-He and Delta-He were strongly associated with lower hemoglobin levels and increased risk of anemia (p < 0.01). Ferritin levels did not predict anemia in either period.

Conclusion

RET-He and Delta-He are valuable predictors of anemia in critically ill ICU patients, outperforming ferritin in this context. Their routine use could improve the early detection and management of iron deficiency and anemia in ICU settings.

Mortality in Critically Ill Patients with Liberal Versus Restrictive Transfusion Thresholds: A Systematic Review and Meta-Analysis of Randomized Controlled Trials with Trial Sequential Analysis

Background/Objectives: Anemia is common in critically ill patients, yet red blood cell (RBC) transfusion without active bleeding does not consistently improve outcomes and carries risks such as pulmonary injury, fluid overload, and increased costs. Optimal transfusion thresholds remain debated, with some guidelines recommending a restrictive target of 7 g/dL instead of a more liberal target of 9 g/dL. Methods: We conducted a systematic review and meta-analysis following PRISMA guidelines, searching PubMed, EMBASE, and LILACS from January 1995 to October 2024. Thirteen randomized controlled trials involving 13,705 critically ill adults were included, with 6855 assigned to liberal and 6850 to restrictive transfusion strategies. The risk of bias was assessed using the Cochrane Risk of Bias Tool 2, and the pooled effect sizes were estimated with a random-effects model. We registered the protocol in PROSPERO International Prospective Register of Systematic Reviews (CDR42024589225). Results: No statistically significant difference was observed in 30-day mortality between restrictive and liberal strategies (odds ratio [OR] 1.02; 95% confidence interval [CI], 0.83-1.25; I2 = 49%). Similarly, no significant differences emerged for the 90-day or 180-day mortality, hospital or intensive care unit (ICU) length of stay, dialysis requirement, or incidence of acute respiratory distress syndrome (ARDS). However, patients in the restrictive group received significantly fewer RBC units. The trial sequential analysis (TSA) indicated that the evidence accrued was insufficient to definitively confirm or exclude an effect on the 30-day mortality, as the required sample size was not reached. Conclusions: In conclusion, while our meta-analysis found no statistically significant difference in the short-term mortality between restrictive and liberal transfusion strategies, larger trials are needed to fully determine whether any clinically meaningful difference exists in critically ill populations.

Practical Anemia Bundle and Hemoglobin Recovery in Critical Illness: A Randomized Clinical Trial

Importance

Anemia is a common complication of surgery and acute illness that is associated with adverse clinical outcomes. The role of anemia prevention and treatment strategies in this setting remains unclear.

Objective

To evaluate the effect of a multifaceted anemia management bundle vs standard care on posthospitalization hemoglobin recovery and multidimensional functional outcomes in survivors of acute illness.

Design, Setting, and Participants

This parallel group randomized clinical trial, known as the Practical Anemia Bundle for Sustained Blood Recovery, was conducted at postsurgical and medical intensive care units at a large US medical center. Critically ill patients (aged ≥18 years) with moderate to severe anemia (hemoglobin concentration <10 g/dL) were enrolled between March 2022 and November 2023. Participants were randomly assigned 1:1 to the intervention or standard care group. Intention-to-treat analyses were performed between July 2024 and January 2025.

Intervention

The intervention bundle was delivered throughout the duration of hospitalization and included optimized phlebotomy practices, clinical decision support, and pharmacological anemia treatment with intravenous iron.

Main Outcomes and Measures

The primary outcome was the mean difference in hemoglobin concentration at 1 month after hospital discharge.

Results

A total of 100 patients (median [IQR] age, 68 [61-72] years; 57 men [57.0%]; 65 [65.0%] with postsurgical admission to the intensive care unit) were enrolled during acute illness. Forty-nine patients (49.0%) were assigned to receive the intervention, and 51 (51.0%) were assigned to receive standard care. Hemoglobin concentration at 1 month after discharge was greater in patients receiving the intervention vs standard care (median [IQR], 12.2 [11.8-13.0] g/dL vs 11.5 [10.2-12.6] g/dL; adjusted mean difference, 0.69 [95% CI, 0.13-1.20] g/dL; P = .02).

Conclusions and Relevance

This randomized clinical trial found that a multifaceted anemia prevention and treatment bundle was feasible, was well tolerated, and improved posthospitalization hemoglobin concentrations up to 3 months in critically ill adults. These findings can inform the design of future trials.

Trial Registration

ClinicalTrials.gov Identifier: NCT05167734.

Design and Staged Implementation of a Multidisciplinary Preoperative Anemia Clinic at a Tertiary Care Medical Center

BACKGROUND

Preoperative anemia is common and associated with adverse outcomes in surgical patients. There is limited information to guide the design and implementation of preoperative anemia clinics (PAC), which represents a critical barrier to entry for many practices.

METHODS

This is a descriptive observational study highlighting the design and implementation of a multidisciplinary PAC, including key steps in planning, stakeholder engagement, organizational structure, identification of target populations, establishing anemia treatments, information technology and electronic health record integration, provider training, and data infrastructure. Demographic and clinical characteristics, laboratory results, and anemia treatments for individuals evaluated in the PAC from November 4, 2019 through September 15, 2023 are enumerated. Patient-reported outcomes (PROs) assessing changes in anemia symptoms and well-being after surgery are evaluated for 2 subsets of patients (one before PAC implementation [pre-PAC], another after PAC implementation [post-PAC]), without formal statistical comparison given limited sample sizes.

RESULTS

The PAC was initiated as a multidisciplinary effort under support from a Mayo Clinic Practice Transformation Award in 2019, including broad representation from anesthesiology, surgery, and medical practices, along with institutional project management support (eg, project manager, information technologists, systems engineers). While initially limited to cardiac surgery patients, the PAC underwent planned incremental expansion to include other surgical services. Over the study period, 1188 PAC consultations across 1159 unique patients met eligibility criteria, with a median age of 66 (57-73) years and 58.1% women. The most common etiology of anemia was iron deficiency (69.1%) followed by anemia related to cancer (17.3%). Anemia-directed therapies were recommended in 1038 (87.4%) encounters, with 730 (70.3%) of those receiving recommended treatment preoperatively. Seven hundred nine (97.1%) treatments included intravenous iron and 146 (20.0%) included erythropoiesis-stimulating agents. Fifteen pre-PAC and 38 post-PAC implementation patients completed PROs. PAC implementation was accompanied by earlier resolution of anemia symptoms and less pronounced declines in postoperative well-being scores.

CONCLUSIONS

This report highlights the key steps for successful PAC implementation. Treatment is possible for most patients and may be accompanied by improvements in patient-important outcomes.

The association of donor and recipient sex on sepsis rates and hemoglobin increment among critically ill patients receiving red cell transfusions in a retrospective study

Background

Existing research presents conflicting results on the influence of blood donor sex on hemoglobin (Hb) change and transfusion-associated infection and mortality in transfusion recipients.

Aim

This retrospective study explored the association between donor and recipient sex on hospital-onset sepsis (HO-sepsis) and Hb changes in critically ill patients receiving red blood cell (RBC) transfusions.

Methods

Data from 2010-2020 were extracted from an academic hospital's clinical database and a blood supplier's donor database. HO-sepsis was determined based on the International Classification of Diseases and Related Health Problems 10th Revision (ICD-10) diagnostic codes without requiring a microbiology test within the first 48 h of admission. Hb increments were determined by comparing the last Hb result in the 24-h period prior to RBC unit issue and the first Hb result within 4-24 h after RBC unit issued for transfusion.

Results

25,585 critically ill patients received one or more RBC transfusions; 3,410 were included in the HO-sepsis and 3,487 in the Hb increment analysis. There was no significant differences in the HO-sepsis rate among the four groups, but female recipients were more prone to HO-sepsis than males (OR 1.48, p = 0.04). Multivariate analysis found that the number of RBC unit transfused (p = 0.001) and recipient age (p = 0.03), but not recipient sex (p = 0.63), were significant contributors to HO-sepsis. Male blood was associated with higher Hb than female blood in female recipients (p = 0.007), but not in male recipients (p = 0.75). Variables such as donor Hb levels and recipient Hb level influenced Hb increments.

Conclusion

Blood donor sex was not associated with HO-sepsis in critically ill patients receiving RBC transfusion. Male to female transfusions were associated with a higher Hb increment in recipients. Further exploration of the impact of sex mis-matched transfusion on recipient outcomes is warranted.

Red Blood Cell-Related Phenotype-Genotype Correlations in Chronic and Acute Critical Illnesses (Traumatic Brain Injury Cohort and COVID-19 Cohort)

Changes in red blood cell (RBC)-related parameters and anemia are common in both severe chronic and acute diseases. RBC-related phenotypes have a heritable component. However, it is unclear whether the contribution of genetic variability is pronounced when hematological parameters are affected by physiological stress. In this study, we analyzed RBC-related phenotypes and phenotype-genotype correlations in two exome-sequenced patient cohorts with or at a high risk for a critical illness: chronic TBI patients admitted for rehabilitation and patients with acute COVID-19. In the analysis of exome data, we focused on the cumulative effects of rare high-impact variants (qualifying variants, QVs) in specific gene sets, represented by Notch signaling pathway genes, based on the results of enrichment analysis in anemic TBI patients and three predefined gene sets for phenotypes of interest derived from GO, GWAS, and HPO resources. In both patient cohorts, anemia was associated with the cumulative effects of QVs in the GO (TBI: p = 0.0003, OR = 2.47 (1.54-4.88); COVID-19: p = 0.0004, OR = 2.12 (1.39-3.25)) and Notch pathway-derived (TBI: p = 0.0017, OR = 2.33 (1.35-4.02); COVID-19: p = 0.0012, OR =8.00 (1.79-35.74)) gene sets. In the multiple linear regression analysis, genetic variables contributed to RBC indices in patients with TBI. In COVID-19 patients, QVs in Notch pathway genes influenced RBC, HGB, and HCT levels, whereas genes from other sets influenced MCHC levels. Thus, in this exploratory study, exome data analysis yielded similar and different results in the two patient cohorts, supporting the view that genetic factors may contribute to RBC-related phenotypic performance in both severe chronic and acute health conditions.

The Role of Ferritin and Folate in Determining Stem Cell Collection for Autologous Stem Cell Transplant in Multiple Myeloma

BACKGROUND

An autologous stem cell transplant (ASCT) is the standard of care for eligible patients with multiple myeloma (MM). However, the success of ASCT largely hinges on efficient mobilization; thus, a thorough analysis of factors that may affect mobilization is essential.

METHODS

The study consists of a single-center, retrospective chart review of 292 adult patients undergoing their first or second autologous transplantation for MM from 2016 to 2023. Patient demographics, serum lab values at the pre-collection evaluation visit, total stem cell capture (TC) in CD34/kg × 106 stem cell capture on the first day of apheresis (FC) in CD34/kg × 106, and the total number of days of apheresis (DOA) were retrieved from the electronic medical record (EMR).

RESULTS

Individuals with high folate levels experienced less DOA (1.43 ± 0.61) compared to those with normal folate levels (1.68 ± 0.82, p = 0.013). The high-folate group had a greater FC (3.26 ± 1.07) compared to the normal-folate group (2.88 ± 1.13, p = 0.013). High ferritin levels were associated with more DOA (1.79 ± 0.89) compared to the normal-ferritin group (1.51 ± 0.67, p = 0.034). Moderate anemia was significantly associated with decreased FC (p = 0.023) and increased DOA (p = 0.030). Abnormal hemoglobin (Hgb), ferritin, and folate statuses did not exhibit significant differences in survival analysis.

CONCLUSIONS

The findings reveal that folate, ferritin, and Hgb levels are significantly associated with apheresis outcomes, offering guidance for optimizing stem cell mobilization in patients with MM.

Association between hemoglobin and in-hospital mortality in critically ill patients with sepsis: evidence from two large databases

BACKGROUND

The relationship between baseline hemoglobin levels and in-hospital mortality in septic patients remains unclear. This study aimed to clarify this association in critically ill patients with sepsis.

METHODS

Patients with sepsis were retrospectively identified from the Medical Information Mart for Intensive Care-IV (MIMIC-IV 2.2) and eICU Collaborative Research Database (eICU-CRD). Multivariate logistic regression analysis and restricted cubic spline regression were used to investigate the association between hemoglobin and the risk of in-hospital mortality. Additionally, a two-part linear regression model was used to determine threshold effects. Stratified analyses were also performed.

RESULTS

A total of 21,946 patients from MIMIC-IV and 15,495 patients from eICU-CRD were included in the study. In-hospital mortality was 14.95% in MIMIC-IV and 17.40% in eICU-CRD. Multivariate logistic regression showed that hemoglobin was significantly and nonlinearly associated with the risk of in-hospital mortality after adjusting for other covariates. Furthermore, we found a nonlinear association between hemoglobin and in-hospital mortality, with mortality plateauing at 10.2 g/dL. The risk of mortality decreased with increasing hemoglobin levels below 10.2 g/dL but increased when hemoglobin levels exceeded 10.2 g/dL. These findings were validated in the eICU-CRD dataset.

CONCLUSIONS

A nonlinear correlation between hemoglobin levels and in-hospital mortality was observed in patients with sepsis, with a threshold of 10.2 g/DL. These findings suggested that hemoglobin levels below or above the threshold may be associated with worse outcomes, warranting further investigation in prospective studies.

Hemoglobin levels and cognitive trajectory: unveiling prognostic insights in post-stroke geriatric cohort

PURPOSE

Evidence is scarce regarding the association between anemia and alterations in cognitive level among hospitalized older patients. We aimed to evaluate the associations between baseline hemoglobin (Hb) levels and changes in cognitive level in patients undergoing rehabilitation after stroke.

METHODS

A retrospective cohort study was conducted, encompassing consecutively hospitalized post-stroke patients. Data on serum Hb levels were extracted from medical records, specifically tests conducted within 24 hours of admission. Primary outcomes included discharge scores for cognitive function assessed by the cognitive domain of the Functional Independence Measure (FIM-cognition) and the corresponding change in FIM-cognition during hospitalization. Another outcome measure was the length of hospital stay. Multivariate linear regression analyses were employed to assess the association between Hb levels at admission and the designated outcomes, adjusting for potential confounding factors.

RESULTS

Data from 955 patients (mean age 73.2 years; 53.6% men) were included in the analysis. The median Hb level at admission was 13.3 [11.9, 14.5] g/dL. After fully adjusting for confounding factors, the baseline Hb level was significantly and positively associated with FIM-cognition at discharge (β = 0.045, p = 0.025) and its gain (β = 0.073, p = 0.025). Further, the baseline Hb level was independently and negatively associated with length of hospital stay (β = -0.013, p = 0.026).

CONCLUSION

Elevated baseline Hb levels are correlated with preserved cognitive level and shorter hospital stays in post-stroke patients. Evaluating anemia at the outset serves as a crucial prognostic indicator.

Complete blood count, coagulation biomarkers, and lung function 6 months after critical COVID-19

BACKGROUND

Understanding the recovery of post-COVID-19 organ dysfunction is essential. We evaluated coagulation 6 months post-COVID-19, examining its recovery and association with lung function.

METHODS

Patients treated for COVID-19 at intensive care units between 3/2020 and 1/2021 were analyzed for complete blood count (CBC) and coagulation biomarkers (prothrombin time activity (%) (PT%), activated partial thromboplastin time (APTT), fibrinogen, coagulation factor VIII (FVIII), antithrombin (AT), and D-dimer) during the 6 months post-hospitalization. Results were compared with acute phase values and correlated with pulmonary function tests (PFT), including forced vital capacity (FVC) and hemoglobin-corrected diffusing capacity percentage of predicted (DLCOc%), recorded 6 months post-hospitalization. We examined the association between coagulation biomarkers and DLCOc% using linear regression with age, sex, and invasive mechanical ventilation (IMV) duration, and FVIII (correlated with DLCOc%) as covariates.

RESULTS

Most CBCs and coagulation biomarkers had median values within the normal range. However, only 21% (15/70) of patients achieved full normalization of all biomarkers. Compared to acute COVID-19, hemoglobin, PT%, and AT increased, while leukocytes, fibrinogen, FVIII, and D-dimer decreased. Despite decreased levels, FVIII remained elevated in 46% (31/68), leukocytes in 26% (18/70), and D-dimer in 27% (18/67) at 6 months. A weak negative correlation (r = -0.37, p = .036) was found between DLCOc% and FVIII. Multivariable analysis revealed a weak, independent association between DLCOc% and FVIII. Excluding patients with anticoagulation therapy, FVIII no longer correlated with DLCOc%, while AT showed a moderate correlation with DLCOc%.

CONCLUSION

Only a few patients had normal CBC and coagulation biomarker values 6 months after critical COVID-19. A weak negative correlation between DLCOc% and FVIII suggests that deranged coagulation activity may be associated with reduced diffusing capacity.

Prevalence and factors influencing anemia recovery after intensive care

BACKGROUND

Anemia is associated with adverse outcomes and prolonged hospitalizations in critically ill patients. Regarding the recent adoption of restrictive transfusion protocols in intensive care unit (ICU) management, anemia remains highly prevalent even after ICU discharge. This study aimed to investigate the prevalence of anemia following ICU discharge and factors affecting recovery from anemia.

METHODS

In this retrospective cohort study involving 3969 adult ICU survivors, we assessed anemia severity using the National Cancer Institute criteria at six time points: ICU admission, ICU discharge, hospital discharge, and at 3-, 6-, and 12-month post-hospital discharge. In addition, baseline characteristics, including age, sex, comorbidities, and recent iron supplementation or erythropoietin administration, were evaluated.

RESULTS

Our findings revealed an in-hospital mortality rate of 28.6%. The median hospital and ICU stays were 20 and 5 days, respectively, with common comorbidities including hypertension, and diabetes mellitus (DM). Among the patients, the hemoglobin levels of 3967 patients were confirmed at the time of discharge from the ICU, representing 99.95% of the total. The prevalence of anemia persisted post- ICU discharge; less than 30% of patients recovered, whereas 13.6% of them experienced worsening of anemia post-ICU discharge. Factors contributing to anemia severity were female sex, DM, chronic renal failure, malignant solid tumors, and administration of iron supplements.

CONCLUSIONS

This study highlighted the need for targeted interventions to manage anemia post-ICU discharge and suggested potential factors that influence recovery from anemia.

The incidence and factors associated with anemia in elective surgical patients admitted to a surgical intensive care unit: a retrospective cohort study

BACKGROUND

Anemia is a frequently reported and commonly documented issue in intensive care units. In surgical intensive care units, more than 90% of patients are found to be anemic. It is a hematologic factor that contributes to extended mechanical ventilation, sepsis, organ failure, longer hospitalizations in critical care units, and higher mortality. Thus, this study aimed to determine the incidence and identify factors associated with anemia in elective surgical patients admitted to the surgical intensive care unit.

METHODS

A retrospective follow-up study involving 422 hospitalized patients was carried out between December 2019 and December 2022 in the surgical intensive care unit after elective surgery at Tikur-Anbessa Specialized Hospital, Addis Ababa, Ethiopia. Data were gathered from the patients' charts, and study participants were chosen using methods of systematic random sampling. SPSS 26 (the statistical software for social science, version 26) was used to analyze the data. Bivariable and multivariable binary logistic regression were used to examine associations between variables.

RESULTS

The incidence of anemia in elective surgical patients admitted to the intensive care unit was 69.9% (95% CI 65.4-74.5%). American Society of Anesthesiologists' class III (ASA III) [AOR: 8.53, 95% CI 1.92-13.8], renal failure [AOR:2.53, 95% CI (1.91-5.81)], malignancy [AOR: 2.59, 95% CI (1.31-5.09)], thoracic surgery [AOR: 4.07, 95% CI (2.11-7.87)], urologic surgery [AOR: 6.22, 95% CI (2.80-13.80)], and neurosurgery [AOR: 4.51, 95% CI (2.53-8.03)] were significantly associated with anemia in surgical patients admitted to the intensive care unit.

CONCLUSION

More than two-thirds of the intensive care unit-admitted surgical patients experienced anemia. An American Society of Anesthesiologists' (ASA III score), renal failure, malignancy, thoracic surgery, urologic surgery, and neurosurgery were significantly associated with this condition. Early identification helps to institute preventive and therapeutic measures.

Anti-inflammatory therapies are associated with delayed onset of anemia and reduction in transfusion requirements in critically ill patients: results from two studies

BACKGROUND

Anemia is a hallmark of critical illness, which is largely inflammatory driven. We hypothesized that the use of anti-inflammatory agents limits the development of anemia and reduces the need for red blood cell (RBC) transfusions in patients with a hyper-inflammatory condition due to COVID-19.

METHODS

An observational cohort (n = 772) and a validation cohort (a subset of REMAP-CAP, n = 119) of critically ill patients with hypoxemic respiratory failure due to COVID-19 were analyzed, who either received no treatment, received steroids or received steroids plus IL-6 blocking agents. The trajectory of hemoglobin (Hb) decline and the need for RBC transfusions were compared using descriptive statistics as well as multivariate modeling.

RESULTS

In both cohorts, Hb level was higher in the treated groups compared to the untreated group at all time points. In the observational cohort, incidence and number of transfused patients were lower in the group receiving the combination treatment compared to the untreated groups. In a multivariate analysis controlling for baseline Hb imbalance and mechanical ventilation, receipt of steroids remained associated with a slower decline in Hb level and the combination treatment remained associated with a slower decline of Hb and with less transfusions. Results remained the same in the validation cohort.

CONCLUSION

Immunomodulatory treatment was associated with a slower decline in Hb level in critically ill patients with COVID-19 and with less transfusion. Findings point toward inflammation as an important cause for the occurrence of anemia in the critically ill.

Haemoglobin thresholds to define anaemia from age 6 months to 65 years: estimates from international data sources

BACKGROUND

Detection of anaemia is crucial for clinical medicine and public health. Current WHO anaemia definitions are based on statistical thresholds (fifth centiles) set more than 50 years ago. We sought to establish evidence for the statistical haemoglobin thresholds for anaemia that can be applied globally and inform WHO and clinical guidelines.

METHODS

In this analysis we identified international data sources from populations in the USA, England, Australia, China, the Netherlands, Canada, Ecuador, and Bangladesh with sufficient clinical and laboratory information collected between 1998 and 2020 to obtain a healthy reference sample. Individuals with clinical or biochemical evidence of a condition that could reduce haemoglobin concentrations were excluded. We estimated haemoglobin thresholds (ie, 5th centiles) for children aged 6-23 months, 24-59 months, 5-11 years, and 12-17 years, and adults aged 18-65 years (including during pregnancy) for individual datasets and pooled across data sources. We also collated findings from three large-scale genetic studies to summarise genetic variants affecting haemoglobin concentrations in different ancestral populations.

FINDINGS

We identified eight data sources comprising 18 individual datasets that were eligible for inclusion in the analysis. In pooled analyses, the haemoglobin fifth centile was 104·4 g/L (90% CI 103·5-105·3) in 924 children aged 6-23 months, 110·2 g/L (109·5-110·9) in 1874 children aged 24-59 months, and 114·4 g/L (113·6-115·2) in 1839 children aged 5-11 years. Values diverged by sex in adolescents and adults. In pooled analyses, the fifth centile was 122·2 g/L (90% CI 121·3-123·1) in 1741 female adolescents aged 12-17 years and 128·2 g/L (126·4-130·0) in 1103 male adolescents aged 12-17 years. In pooled analyses of adults aged 18-65 years, the fifth centile was 119·7 g/L (90% CI 119·1-120·3) in 3640 non-pregnant females and 134·9 g/L (134·2-135·6) in 2377 males. Fifth centiles in pregnancy were 110·3 g/L (90% CI 109·5-111·0) in the first trimester (n=772) and 105·9 g/L (104·0-107·7) in the second trimester (n=111), with insufficient data for analysis in the third trimester. There were insufficient data for adults older than 65 years. We did not identify ancestry-specific high prevalence of non-clinically relevant genetic variants that influence haemoglobin concentrations.

INTERPRETATION

Our results enable global harmonisation of clinical and public health haemoglobin thresholds for diagnosis of anaemia. Haemoglobin thresholds are similar between sexes until adolescence, after which males have higher thresholds than females. We did not find any evidence that thresholds should differ between people of differering ancestries.

FUNDING

World Health Organization and the Bill & Melinda Gates Foundation.

Pharmacotherapy for Reducing RBC Transfusion for Patients in the ICU: A Systematic Review and Network Meta-Analysis

OBJECTIVES

To determine optional therapeutic strategies by comparing monotherapies and combination therapies to reduce RBC transfusion requirement for patients in the ICU.

DATA SOURCES

MEDLINE, CENTRAL, and Embase were searched for studies published from database inception until July 2023.

DATA EXTRACTION

We included randomized controlled trials comparing erythropoiesis-stimulating agents (Epo), iron, combination therapy with iron and Epo, hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI), vitamin D 3 (VD3), and placebo/no treatment. A frequentist network meta-analysis (NMA) was performed using a random effects model, and the confidence in NMA was rated.

DATA SYNTHESIS

Of 117 eligible studies, 75 studies (15,091 patients) were included in the quantitative analysis. Compared with placebo/no treatment, the combination therapy reduces the requirement for RBC transfusion (risk ratio [RR]: 0.60; 95% CI, 0.49-0.74; confidence rating: moderate). The Epo or iron monotherapy may reduce the requirement for RBC transfusion (RR: 0.81; 95% CI, 0.63-1.04; confidence rating: low; RR: 0.83; 95% CI, 0.70-0.98; confidence rating: low, respectively). Combination therapy may not increase the prevalence of both venous thromboembolism (VTE) (RR: 0.73; 95% CI, 0.25-2.08; confidence rating: low) and infection. Epo monotherapy may not increase the prevalence of VTE but may increase that of infections (RR: 1.27; 95% CI, 0.94-1.73; confidence rating: low). Iron monotherapy may not increase the prevalence of both VTE and infection. Evidence for VD3 and HIF-PHI remains uncertain.

CONCLUSIONS

Combination therapy with iron and Epo likely reduces the requirement for RBC transfusion and may be less harmful than other therapies.

Impact of anemia requiring transfusion or erythropoiesis-stimulating agents on new-onset cardiovascular events and mortality after continuous renal replacement therapy

Anemia is common in critically ill patients undergoing continuous renal replacement therapy (CRRT). We investigated the impact of anemia requiring red blood cell (RBC) transfusion or erythropoiesis-stimulating agents (ESAs) on patient outcomes after hospital discharge in critically ill patients with acute kidney injury (AKI) requiring CRRT. In this retrospective cohort study using the Health Insurance Review and Assessment database of South Korea, 10,923 adult patients who received CRRT for 3 days or more between 2010 and 2019 and discharged alive were included. Anemia was defined as the need for RBC transfusion or ESAs. Outcomes included cardiovascular events (CVEs) and all-cause mortality after discharge. The anemia group showed a tendency to be older with more females and had more comorbidities compared to the control group. Anemia was not associated with an increased risk of CVEs (adjusted hazard ratio [aHR]: 1.05; 95% confidence interval [CI]: 0.85-1.29), but was associated with an increased risk of all-cause mortality (aHR: 1.41; 95% CI 1.30-1.53). For critically ill patients with AKI requiring CRRT, anemia, defined as requirement for RBC transfusion or ESAs, may increase the long-term risk of all-cause mortality.

Association of pharmacologic thromboprophylaxis with clinically relevant bleeding and hospital-acquired anemia in medical inpatients: the risk stratification for hospital-acquired venous thromboembolism in medical patients study

BACKGROUND

Pharmacologic thromboprophylaxis (pTPX) might exacerbate the risk of clinically relevant bleeding (CRB) and hospital-acquired anemia (HAA) in older multimorbid inpatients.

OBJECTIVES

We aimed to evaluate the association of pTPX use with CRB and HAA.

METHODS

We used data from a prospective cohort study conducted in 3 Swiss university hospitals. Adult patients admitted to internal medicine wards with no therapeutic anticoagulation were included. pTPX use was ascertained during hospitalization. Outcomes were in-hospital CRB and HAA. We calculated incidence rates by status of pTPX. We assessed the association of pTPX with CRB using survival analysis and with HAA using logistic regression, adjusted for infection, length of stay, and the International Medical Prevention Registry on Venous Thromboembolism bleeding risk score.

RESULTS

Among 1305 patients (mean age, 63.7 years; 44% women, 90% at low risk of bleeding), 809 (62%) received pTPX. The incidence of CRB was 2.4 per 1000 patient-days and was not significantly higher in patients with pTPX than in those without. We found no significant association between pTPX and CRB. HAA was frequent (20.2%) and higher in patients with pTPX than in those without (23.2% vs 15.3%). The incidence of HAA was 21.2 per 1000 patient-days and did not significantly differ between patients with pTPX and those without. We found an association between pTPX and HAA (adjusted odds ratio, 1.4; 95% CI, 1.0-2.1).

CONCLUSION

Our study confirmed the safety of pTPX in medical inpatients at low risk of bleeding but identified an association between pTPX and HAA. Adherence to guidelines that recommend administering pTPX to medical inpatients at increased venous thromboembolism risk and low bleeding risk is necessary.

Low hemoglobin levels are associated with compromised muscle health: Insights from a post-stroke rehabilitation cohort

AIM

There is limited evidence concerning the association between anemia and alterations in muscle health among hospitalized older patients. We aimed to evaluate the associations between baseline hemoglobin (Hb) levels and changes in muscle function in patients undergoing rehabilitation after stroke.

METHODS

This retrospective cohort study included consecutive hospitalized post-stroke patients. Data on serum Hb level were extracted from medical records on tests performed within 24 h of admission. The main outcomes were discharge score for the skeletal muscle mass index (SMI) obtained through bioimpedance analysis and the corresponding change in SMI during hospitalization. Other outcomes were handgrip strength (HGS) at discharge and the alteration in HGS during hospitalization. Multivariate linear regression analyses were used to determine the association between Hb levels at admission and outcomes of interest, adjusted for potential confounders.

RESULTS

Data from 955 patients (mean age 73.2 years; 53.6% men) were included in the analysis. The median Hb level at admission was 13.3 [11.9, 14.5] g/dL. After fully adjusting for confounding factors, the baseline Hb level was significantly and positively associated with SMI at discharge (β = 0.046, P = 0.039) and with SMI gain (β = 0.010, P = 0.039). Further, the baseline Hb level was independently and positively associated with HGS at discharge (β = 0.058, P = 0.014) and with its change from baseline (β = 0.100, P = 0.014).

CONCLUSION

Diminished baseline Hb levels were demonstrated be correlated with compromised muscle health in patients after stroke. Evaluating anemia at the outset serves as a crucial prognostic indicator. Geriatr Gerontol Int 2024; 24: 305-311.

Monitoring the Efficacy of High-Flow Nasal Cannula Oxygen Therapy in Patients with Acute Hypoxemic Respiratory Failure in the General Respiratory Ward: A Prospective Observational Study

High-flow nasal cannula (HFNC) is widely used to treat hypoxemic respiratory failure. The effectiveness of HFNC treatment and the methods for monitoring its efficacy in the general ward remain unclear. This prospective observational study enrolled 42 patients who had acute hypoxemic respiratory failure requiring HFNC oxygen therapy in the general adult respiratory ward. The primary outcome was the all-cause in-hospital mortality. Secondary outcomes included the association between initial blood test results and HFNC outcomes. Regional ventilation distributions were monitored in 24 patients using electrical impedance tomography (EIT) after HFNC initiation. Patients with successful HFNC treatment had better in-hospital survival (94%) compared to those with failed HFNC treatment (0%, p < 0.001). Neutrophil-to-lymphocyte ratios of ≥9 were more common in patients with failed HFNC (70%) compared to those with successful HFNC (52%, p = 0.070), and these patients had shorter hospital survival rates after HFNC treatment (p = 0.046, Tarone-Ware test). Patients with successful HFNC treatment had a more central ventilation distribution compared to those with failed HFNC treatment (p < 0.05). Similarly, patients who survived HFNC treatment had a more central distribution compared to those who did not survive (p < 0.001). We concluded that HFNC in the general respiratory ward may be a potential rescue therapy for patients with respiratory failure. EIT can potentially monitor patients receiving HFNC therapy.

Anemia Recovery After Lung Contusion, Hemorrhagic Shock, and Chronic Stress Is Gender-Specific in a Rat Model

Background: Severe trauma and hemorrhagic shock lead to persistent anemia. Although biologic gender is known to modulate inflammatory responses after critical illness, the impact of gender on anemia recovery after injury remains unknown. The aim of this study was to identify gender-specific differences in anemia recovery after critical illness. Materials and Methods: Male and proestrus female Sprague-Dawley rats (n = 8-9 per group) were subjected to lung contusion and hemorrhagic shock (LCHS) or LCHS with daily chronic stress (LCHS/CS) compared with naïve. Hematologic data, bone marrow progenitor growth, and bone marrow and liver gene transcription were analyzed on day seven. Significance was defined as p < 0.05. Results: Males lost substantial weight after LCHS and LCHS/CS compared with naïve males, while female LCHS rats did not compared with naive counterparts. Male LCHS rats had a drastic decrease in hemoglobin from naïve males. Male LCHS/CS rats had reduced colony-forming units-granulocyte, -erythrocyte, -monocyte, -megakaryocyte (CFU-GEMM) and burst-forming unit-erythroid (BFU-E) when compared with female counterparts. Naïve, LCHS, and LCHS/CS males had lower serum iron than their respective female counterparts. Liver transcription of BMP4 and BMP6 was elevated after LCHS and LCHS/CS in males compared with females. The LCHS/CS males had decreased expression of bone marrow pro-erythroid factors compared with LCHS/CS females. Conclusions: After trauma with or without chronic stress, male rats demonstrated increased weight loss, substantial decrease in hemoglobin level, dysregulated iron metabolism, substantial suppression of bone marrow erythroid progenitor growth, and no change in transcription of pro-erythroid factors. These findings confirm that gender is an important variable that impacts anemia recovery and bone marrow dysfunction after traumatic injury and shock in this rat model.

Chronic Critical Illness in Patients With Sepsis is Associated With Persistent Anemia, Inflammation, and Impaired Functional Outcomes

INTRODUCTION

Survivors of sepsis will progress towards rapid recovery (RAP) or enter a state of persistent organ dysfunction and chronic critical illness (CCI). Independently, anemia is known to be a significant factor in functional recovery of hospitalized patients. This study aims to analyze long-term hemoglobin levels and functional outcomes following RAP and CCI.

METHODS

A prospective, cohort study was performed in septic patients who were stratified into RAP (N = 54) with ICU length of stay < 14 days or CCI (N = 63) with ICU length of stay > 14 days. CBC and plasma inflammatory markers were measured on the day of enrollment, weekly until day 42, then at 3 and 6 months. Functional outcomes using Zubrod scale, gait speed test, and total short physical performance battery (SPPB) were assessed at 3, 6, and 12 months.

RESULTS

Mean age was 59 years (range: 20-83) and 62% were male. Hemoglobin was significantly decreased at 3 and 6 months in CCI compared to RAP (8.9* and 9.2* vs 10.4 and 11.1 g/dL), despite receiving significantly more red blood cell transfusions. CCI patients had persistent elevation of CRP, IL-6 and TNF-α. CCI patients had worse functional outcome with a significantly higher Zubrod score, and lower SPPB, and gait speed score at 3, 6, and 12 months.

CONCLUSION

Despite receiving more pRBC transfusions, CCI patients had a persistent anemia that was associated with chronic systemic inflammation and poor functional outcomes six months following sepsis. Alleviating prolonged inflammation could improve persistent anemia and functional outcomes in CCI patients.

Statistical haemoglobin thresholds to define anaemia across the lifecycle

Detection of anaemia is critical for clinical medicine and public health. Current WHO values that define anaemia are statistical thresholds (5 ^th centile) set over 50 years ago, and are presently <110g/L in children 6-59 months, <115g/L in children 5-11 years, <110g/L in pregnant women, <120g/L in children 12-14 years of age, <120g/L in non-pregnant women, and <130g/L in men. Haemoglobin is sensitive to iron and other nutrient deficiencies, medical illness and inflammation, and is impacted by genetic conditions; thus, careful exclusion of these conditions is crucial to obtain a healthy reference population. We identified data sources from which sufficient clinical and laboratory information was available to determine an apparently healthy reference sample. Individuals were excluded if they had any clinical or biochemical evidence of a condition that may diminish haemoglobin concentration. Discrete 5 ^th centiles were estimated along with two-sided 90% confidence intervals and estimates combined using a fixed-effect approach. Estimates for the 5 ^th centile of the healthy reference population in children were similar between sexes. Thresholds in children 6-23 months were 104.4g/L [90% CI 103.5, 105.3]; in children 24-59 months were 110.2g/L [109.5, 110.9]; and in children 5-11 years were 114.1g/L [113.2, 115.0]. Thresholds diverged by sex in adolescents and adults. In females and males 12-17 years, thresholds were 122.2g/L [121.3, 123.1] and 128.2 [126.4, 130.0], respectively. In adults 18-65 years, thresholds were 119.7g/L [119.1, 120.3] in non-pregnant females and 134.9g/L [134.2, 135.6] in males. Limited analyses indicated 5 ^th centiles in first-trimester pregnancy of 110.3g/L [109.5, 111.0] and 105.9g/L [104.0, 107.7] in the second trimester. All thresholds were robust to variations in definitions and analysis models. Using multiple datasets comprising Asian, African, and European ancestries, we did not identify novel high prevalence genetic variants that influence haemoglobin concentration, other than variants in genes known to cause important clinical disease, suggesting non-clinical genetic factors do not influence the 5 ^th centile between ancestries. Our results directly inform WHO guideline development and provide a platform for global harmonisation of laboratory, clinical and public health haemoglobin thresholds.

The role of the microcirculation and integrative cardiovascular physiology in the pathogenesis of ICU-acquired weakness

Skeletal muscle dysfunction after critical illness, defined as ICU-acquired weakness (ICU-AW), is a complex and multifactorial syndrome that contributes significantly to long-term morbidity and reduced quality of life for ICU survivors and caregivers. Historically, research in this field has focused on pathological changes within the muscle itself, without much consideration for their in vivo physiological environment. Skeletal muscle has the widest range of oxygen metabolism of any organ, and regulation of oxygen supply with tissue demand is a fundamental requirement for locomotion and muscle function. During exercise, this process is exquisitely controlled and coordinated by the cardiovascular, respiratory, and autonomic systems, and also within the skeletal muscle microcirculation and mitochondria as the terminal site of oxygen exchange and utilization. This review highlights the potential contribution of the microcirculation and integrative cardiovascular physiology to the pathogenesis of ICU-AW. An overview of skeletal muscle microvascular structure and function is provided, as well as our understanding of microvascular dysfunction during the acute phase of critical illness; whether microvascular dysfunction persists after ICU discharge is currently not known. Molecular mechanisms that regulate crosstalk between endothelial cells and myocytes are discussed, including the role of the microcirculation in skeletal muscle atrophy, oxidative stress, and satellite cell biology. The concept of integrated control of oxygen delivery and utilization during exercise is introduced, with evidence of physiological dysfunction throughout the oxygen delivery pathway - from mouth to mitochondria - causing reduced exercise capacity in patients with chronic disease (e.g., heart failure, COPD). We suggest that objective and perceived weakness after critical illness represents a physiological failure of oxygen supply-demand matching - both globally throughout the body and locally within skeletal muscle. Lastly, we highlight the value of standardized cardiopulmonary exercise testing protocols for evaluating fitness in ICU survivors, and the application of near-infrared spectroscopy for directly measuring skeletal muscle oxygenation, representing potential advancements in ICU-AW research and rehabilitation.

[Implementation of Patient Blood Management as Standard-of-Care]

Anaemia is among the most common co-morbidity in surgical patients. However, it often remains unrecognized and untreated, which results in an increased requirement for allogeneic blood products and complications. Patient Blood Management offers patient-centred and evidence-based therapies and preventive measures for anaemia. Patient Blood Management is composed of 3 main pillars: pre-operative anaemia management, blood loss reduction and the rational use of allogeneic blood products. The World Health Organization demands the implementation of Patient Blood Management measures since 2010. However, a comprehensive implementation of Patient Blood Management as a standard-of-care is still not achieved. Here, we describe the need for a comprehensive Patient Blood Management implementation and highlight several specific Patient Blood Management measures.

Anaemia in the first week may be associated with long-term mortality among critically ill patients: propensity score-based analyses

BACKGROUND

Anaemia is highly prevalent in critically ill patients; however, the long-term effect on mortality remains unclear.

METHODS

We retrospectively included patients admitted to the medical intensive care units (ICUs) during 2015-2020 at the Taichung Veterans General Hospital. The primary outcome of interest was one-year mortality, and hazard ratios (HRs) with 95% confidence intervals (CIs) were determined to assess the association. We used propensity score matching (PSM) and propensity score matching methods, including inverse probability of treatment weighting (IPTW) as well as covariate balancing propensity score (CBPS), in the present study.

RESULTS

A total of 7,089 patients were eligible for analyses, and 45.0% (3,189/7,089) of them had anaemia, defined by mean levels of haemoglobin being less than 10 g/dL. The standardised difference of covariates in this study were lower than 0.20 after matching and weighting. The application of CBPS further reduced the imbalance among covariates. We demonstrated a similar association, and adjusted HRs in original, PSM, IPTW and CBPS populations were 1.345 (95% CI 1.227-1.474), 1.265 (95% CI 1.145-1.397), 1.276 (95% CI 1.142-1.427) and 1.260 (95% CI 1.125-1.411), respectively.

CONCLUSIONS

We used propensity score-based analyses to identify that anaemia within the first week was associated with increased one-year mortality in critically ill patients.

Central Line Access Is Predictive of Diagnostic Blood Loss and Transfusion in the Surgical Intensive Care Unit

BACKGROUND

Most patients in the surgical intensive care unit (SICU) have anemia and undergo extensive diagnostic laboratory testing (DLT). Consequently, patients undergo RBC transfusion, and many are discharged with anemia, both of which are associated with poorer outcomes.

OBJECTIVE

To characterize DLT blood loss in the SICU.

MATERIALS AND METHODS

We performed a 1-year retrospective study of 291 patients admitted to a SICU. The number of draws, average volume, and estimated discard volume were recorded, along with clinical and laboratory findings.

RESULTS

Patients who underwent greater amounts of DLT had lower hemoglobin levels at discharge (P ≤ .001). Admissions requiring central venous catheter (CVC) access (49.8%) demonstrated significantly higher DLT draws and rates of transfusion.

CONCLUSION

Findings from this study suggest that DLT blood loss contributes to anemia in the SICU, and that the presence and duration of CVC leads to increased testing, anemia, and RBC transfusion.

Patient Blood Management, Anemia, and Transfusion Optimization Across Surgical Specialties

Patient blood management (PBM) is a systematic, evidence-based approach to improve patient outcomes by managing and preserving a patient's own blood and minimizing allogenic transfusion need and risk. According to the PBM approach, the goals of perioperative anemia management include early diagnosis, targeted treatment, blood conservation, restrictive transfusion except in cases of acute and massive hemorrhage, and ongoing quality assurance and research efforts to advance overall blood health.

Blood count derangements after sepsis and association with post-hospital outcomes

Rationale

Predicting long-term outcomes in sepsis survivors remains a difficult task. Persistent inflammation post-sepsis is associated with increased risk for rehospitalization and death. As surrogate markers of inflammation, complete blood count parameters measured at hospital discharge may have prognostic value for sepsis survivors.

Objective

To determine the incremental value of complete blood count parameters over clinical characteristics for predicting 90-day outcomes in sepsis survivors.

Methods

Electronic health record data was used to identify sepsis hospitalizations at United States Veterans Affairs hospitals with live discharge and relevant laboratory data (2013 to 2018). We measured the association of eight complete blood count parameters with 90-day outcomes (mortality, rehospitalization, cause-specific rehospitalizations) using multivariable logistic regression models.

Measurements and main results

We identified 155,988 eligible hospitalizations for sepsis. Anemia (93.6%, N=142,162) and lymphopenia (28.1%, N=29,365) were the most common blood count abnormalities at discharge. In multivariable models, all parameters were associated with the primary outcome of 90-day mortality or rehospitalization and improved model discrimination above clinical characteristics alone (likelihood ratio test, p<0.02 for all). A model including all eight parameters significantly improved discrimination (AUROC, 0.6929 v. 0.6756) and reduced calibration error for the primary outcome. Hemoglobin had the greatest prognostic separation with a 1.5 fold increased incidence of the primary outcome in the lowest quintile (7.2-8.9 g/dL) versus highest quintile (12.70-15.80 g/dL). Hemoglobin and neutrophil lymphocyte ratio provided the most added value in predicting the primary outcome and 90-day mortality alone, respectively. Absolute lymphocyte count added little value in predicting 90-day outcomes.

Conclusions

The incorporation of discharge complete blood count parameters into prognostic scoring systems could improve prediction of 90-day outcomes. Hemoglobin had the greatest prognostic value for the primary composite outcome of 90-day rehospitalization or mortality. Absolute lymphocyte count provided little added value in multivariable model comparisons, including for infection- or sepsis-related rehospitalization.

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.

Effects of ferric carboxymaltose on hemoglobin level after cardiac surgery: A randomized controlled trial

BACKGROUND

Perioperative anemia is common in cardiac surgery. Few studies investigated the effect of postoperative intravenous (IV) iron supplementation and were mostly inconclusive.

METHODS

Design: A randomized single-center, double-blind, placebo-controlled, parallel-group trial.

PARTICIPANTS

195 non-anemic patients were recruited from December 2018 to December 2020: 97 patients received 1 g of ferric carboxymaltose (FCM) and 98 patients received 100 mL of physiological serum on postoperative day 1.

MEASUREMENTS

hemoglobin levels, reticulocyte count, serum iron, serum ferritin, and transferrin saturation were measured at induction of anesthesia, postoperative days 1, 5, and 30. Transfusion rate, duration of mechanical ventilation, critical care unit length of stay, and side effects associated with IV iron administration were measured. The primary outcome was hemoglobin level on day 30. Secondary outcomes included iron balance, transfused red cell packs, and critical care unit length of stay.

RESULTS

At day 30, the hemoglobine level was higher in the FCM group than in the placebo group (mean 12.9 ± 1.2 vs. 12.1 ± 1.3 g/dL (95%CI 0.41-1.23, p-value <0.001)). Patients in the FCM group received fewer blood units (median 1[0-2] unit vs. 2 [0-3] units, p-value = 0.037) and had significant improvement in iron balance compared to the control group. No side effects associated with FCM administration were reported.

CONCLUSION

In this randomized controlled trial, administration of FCM on postoperative day 1 in non-anemic patients undergoing cardiac surgery increased hemoglobin levels by 0.8 g/dL on postoperative day 30, leading to reduced transfusion rate, and improved iron levels on postoperative day 5 and 30.

CLINICAL TRIAL REGISTRY NUMBER

NCT03759964.

Anemia Recovery after Trauma: A Longitudinal Study

Background: Post-injury inflammation and its correlation with anemia recovery after severe trauma is poorly described. Severe injury induces a systemic inflammatory response associated with critical illness and organ dysfunction, including disordered hematopoiesis, and anemia. This study sought to characterize the resolution of post-injury inflammation and anemia to identify risk factors associated with persistence of anemia. Patients and Methods: This single-institution study prospectively enrolled 73 trauma patients with an injury severity score >15, hemorrhagic shock, and a lower extremity long bone orthopedic injury. Blood was obtained at enrollment and after 14 days, one, three, and six months. Analytes were compared using Mann-Whitney U tests with correction for multiple comparisons. Results: Median age was 45 years and Injury Severity Score (ISS) was 27, with anemia rates of 97% at two weeks, 80% at one month, 52% at three months, and 30% at six months. Post-injury elevations in erythropoietin, interleukin-6, and C-reactive protein resolved by one month, three months, and six months, respectively. Median granulocyte colony-stimulating factor (G-CSF) and tumor necrosis factor (TNF)-α concentrations remained elevated throughout the six-month follow-up period. Patients with persistent anemia had longer intensive care unit and hospital lengths of stay, more infectious complications, and received more packed red blood cell transfusions compared to those with early anemia recovery. Conclusions: Severe trauma is associated with a prolonged inflammatory response, which is associated with increased transfusion requirements, lengths of stay, and persistent anemia. Further analysis is needed to identify correlations between prolonged inflammation and clinical outcomes after discharge.

Prevalence and risk factors for hospital-acquired anemia in internal medicine patients: learning from the "less is more" perspective

Hospital-acquired anemia is defined as a new-onset anemia in hospitalized patients who have a normal hemoglobin level at admission. Its prevalence is unknown and most studies published on this topic have been conducted in intensive care unit patients with limited applicability to less acute settings, such as internal medicine wards. We conducted a retrospective study and enrolled 129 patients who were admitted to an Internal Medicine Unit between October 2021 and February 2022. The median value of phlebotomy during hospitalization was 46 ml (IQR 30-72 ml), whereas the median length of hospital stay was 9 days (IQR 5-13 days). The median value of hemoglobin reduction was -0.63 g/dl (p < 0.001) and the maximum value of drop in hemoglobin value was -2.6 g/dl. All patients who experienced a phlebotomy > 85 ml had a hemoglobin reduction > 0.6 g/dl. 20.9% of patients developed anemia during the hospital stay (7% moderate and 13.9% mild). No cases of severe anemia were observed. The volume of blood drawn during the hospital stay and the Hb value on admission were the only two variables statistically associated with the development of anemia, whereas gender, age, and chronic diseases, such as diabetes, history of cancer, or heart failure, were not. Strategies, such as elimination of unnecessary laboratory tests and the use of smaller tubes for blood collection, are needed to reduce the volume of iatrogenic blood loss and avoid blood wastage occurring during hospitalization in internal medicine patients.

Association between anaemia and hospital readmissions in patients undergoing major surgery requiring postoperative intensive care

Anaemia is a common sequela of surgery, although its relationship with patient recovery is unclear. The goal of this investigation was to assess the associations between haemoglobin concentrations at the time of hospital discharge following major surgery and early post-hospitalisation outcomes, with a primary outcome of 30 day unanticipated hospital readmissions. This investigation includes data from two independent population-based observational cohorts of adult surgical patients (aged ≥ 18 years) requiring postoperative intensive care unit admission between 1 January 2010 and 31 December 2019 in hospitals in Olmsted County, Minnesota, and between 1 July 2010 and 30 June 2017 in the Kaiser Permanente Northern California integrated healthcare system, California. Cox proportional hazards models assessed the associations between discharge haemoglobin concentrations (per 10 g.l-1 ) and outcomes, with prespecified multivariable adjustment. A total of 3260 patients were included from Olmsted County hospitals and 29,452 from Kaiser Permanente Northern California. In adjusted analyses, each 10 g.l-1 decrease in haemoglobin at hospital discharge was associated with a 9% (hazard ratio 1.09, 95%CI 1.02-1.18; p = 0.014) and 8% increase (hazard ratio 1.08, 95%CI 1.06-1.11; p < 0.001) in the hazard for readmission within 30 days in Olmsted County and Kaiser Permanente Northern California, respectively. In a sensitivity analysis exploring relationships across varying levels of pre-operative anaemia severity, these associations remained consistent, with lower discharge haemoglobin concentrations associated with higher readmissions irrespective of pre-operative anaemia severity. Anaemia at hospital discharge in surgical patients requiring postoperative intensive care is associated with increased rates of hospital readmission in two large independent cohorts. Future studies are necessary to evaluate strategies to prevent and/or treat anaemia in these patients for the improvement of post-hospitalisation outcomes.

Practical Anemia Bundle for Sustained Blood Recovery (PABST-BR) in critical illness: a protocol for a randomised controlled trial

INTRODUCTION

Anaemia is highly prevalent in critical illness and is associated with impaired outcomes during and after hospitalisation. However, the impact of interventions designed to attenuate or treat anaemia during critical illness on post-hospitalisation haemoglobin recovery and functional outcomes is unclear.

METHODS AND ANALYSIS

The Practical Anemia Bundle for Sustained Blood Recovery (PABST-BR) clinical trial is a pragmatic, open-label, parallel group, single-centre, randomised clinical trial assessing the impact of a multifaceted anaemia prevention and treatment strategy versus standard care for improvement of haemoglobin concentrations and functional outcomes after critical illness. The intervention, which will be delivered early in critical illness for those with moderate-to-severe anaemia (ie, haemoglobin <100 g/L), includes three components: (1) optimised phlebotomy, (2) clinical decision support and (3) pharmacological anaemia treatment directed at the underlying aetiology of anaemia. In-person assessments will occur at 1 and 3 months post-hospitalisation for laboratory evaluations and multidimensional functional outcome assessments. The primary outcome is differences in haemoglobin concentrations between groups, with secondary endpoints of anaemia-related fatigue, physical function, cognition, mental health, quality of life, phlebotomy volumes and frequency, transfusions, readmissions and mortality through 1-year post-hospitalisation.

ETHICS AND DISSEMINATION

The study has been approved by the Institutional Review Board of the Mayo Clinic in Minnesota, USA. A Data Safety Monitoring Plan has been created in accordance with the policies of the Institutional Review Board and the study funder, the National Heart, Lung and Blood Institute of the National Institutes of Health (NIH). The study will comply with NIH data sharing and dissemination policies. Results will be presented at national and international meetings and published in peer-reviewed journals. Designing and testing strategies to optimise haemoglobin recovery and improve functional outcomes after critical illness remain important research gaps. The PABST-BR trial will inform the development of a larger multicentre clinical trial.

TRIAL REGISTRATION NUMBER

NCT05167734.

Early Post-Hospitalization Hemoglobin Recovery and Clinical Outcomes in Survivors of Critical Illness: A Population-Based Cohort Study

Anemia is common during critical illness, is associated with adverse clinical outcomes, and often persists after hospitalization. The goal of this investigation is to assess the relationships between post-hospitalization hemoglobin recovery and clinical outcomes after survival of critical illness. This is a population-based observational study of adults (≥18 years) surviving hospitalization for critical illness between January 1, 2010 and December 31, 2016 in Olmsted County, Minnesota, United States with hemoglobin concentrations and clinical outcomes assessed through one-year post-hospitalization. Multi-state proportional hazards models were utilized to assess the relationships between 1-month post-hospitalization hemoglobin recovery and hospital readmission or death through one-year after discharge. Among 6460 patients that survived hospitalization for critical illness during the study period, 2736 (42%) were alive, not hospitalized, and had available hemoglobin concentrations assessed at 1-month post-index hospitalization. Median (interquartile range) age was 69 (56, 80) years with 54% of male gender. Overall, 86% of patients had anemia at the time of hospital discharge, with median discharge hemoglobin concentrations of 10.2 (9.1, 11.6) g/dL. In adjusted analyses, each 1 g/dL increase in 1-month hemoglobin recovery was associated with decreased instantaneous hazard for hospital readmission (HR 0.87 [95% CI 0.84-0.90]; p < 0.001) and lower mortality (HR 0.82 [95% CI 0.75-0.89]; p < 0.001) through one-year post-hospitalization. The results were consistent in multiple pre-defined sensitivity analyses. Impaired early post-hospitalization hemoglobin recovery is associated with inferior clinical outcomes in the first year of survival after critical illness. Additional investigations are warranted to evaluate these relationships.

Impact of Blood Sampling on Anemia in the PICU: A Prospective Cohort Study

OBJECTIVES

Fifty percent of children are anemic after a critical illness. Iatrogenic blood testing may be a contributor to this problem. The objectives of this study were to describe blood sampling practice in a PICU, determine patient factors associated with increased sampling, and examine the association among blood sampling volume, anemia at PICU discharge, and change in hemoglobin from PICU entry to PICU discharge.

DESIGN

Prospective observational cohort study.

SETTING

PICU of Sainte-Justine University Hospital.

PATIENTS

All children consecutively admitted during a 4-month period.

MEASUREMENTS AND MAIN RESULTS

Four hundred twenty-three children were enrolled. Mean blood volume sampled was 3.9 (±19) mL/kg/stay, of which 26% was discarded volume. Children with central venous or arterial access were sampled more than those without access (p < 0.05). Children with sepsis, shock, or cardiac surgery were most sampled, those with a primary respiratory diagnosis; the least (p < 0.001). We detected a strong association between blood sample volume and mechanical ventilation (H, 81.35; p < 0.0001), but no association with severity of illness (Worst Pediatric Logistic Organ Dysfunction score) (R, -0.044; p = 0.43). Multivariate analysis (n = 314) showed a significant association between the volume of blood sampled (as continuous variable) and anemia at discharge (adjusted OR, 1.63; 95% CI, 1.18-2.45; p = 0.003). We lacked power to detect an association between blood sampling and change in hemoglobin from PICU admission to PICU discharge.

CONCLUSIONS

Diagnostic blood sampling in PICU is associated with anemia at discharge. Twenty-five percent of blood losses from sampling is wasted. Volumes are highest for patients with sepsis, shock, or cardiac surgery, and in patients with vascular access or ventilatory support.

Explainable machine learning to predict long-term mortality in critically ill ventilated patients: a retrospective study in central Taiwan

BACKGROUND

Machine learning (ML) model is increasingly used to predict short-term outcome in critically ill patients, but the study for long-term outcome is sparse. We used explainable ML approach to establish 30-day, 90-day and 1-year mortality prediction model in critically ill ventilated patients.

METHODS

We retrospectively included patients who were admitted to intensive care units during 2015-2018 at a tertiary hospital in central Taiwan and linked with the Taiwanese nationwide death registration data. Three ML models, including extreme gradient boosting (XGBoost), random forest (RF) and logistic regression (LR), were used to establish mortality prediction model. Furthermore, we used feature importance, Shapley Additive exPlanations (SHAP) plot, partial dependence plot (PDP), and local interpretable model-agnostic explanations (LIME) to explain the established model.

RESULTS

We enrolled 6994 patients and found the accuracy was similar among the three ML models, and the area under the curve value of using XGBoost to predict 30-day, 90-day and 1-year mortality were 0.858, 0.839 and 0.816, respectively. The calibration curve and decision curve analysis further demonstrated accuracy and applicability of models. SHAP summary plot and PDP plot illustrated the discriminative point of APACHE (acute physiology and chronic health exam) II score, haemoglobin and albumin to predict 1-year mortality. The application of LIME and SHAP force plots quantified the probability of 1-year mortality and algorithm of key features at individual patient level.

CONCLUSIONS

We used an explainable ML approach, mainly XGBoost, SHAP and LIME plots to establish an explainable 1-year mortality prediction ML model in critically ill ventilated patients.

Preoperative anemia is a risk factor for poor perioperative outcomes in ventral hernia repair

PURPOSE

Ventral hernia repairs (VHR) are among the most commonly performed operations by general surgeons. Despite advances in technology there remains high complication and readmission rates. Preoperative anemia has been linked to poor outcomes and readmission across several surgical procedures, however the link to ventral hernia repair outcomes is limited.

METHODS

Utilizing the American College of Surgeons National Safety and Quality Improvement Project (NSQIP) database for years 2016-2018, a total of 115,000 patients met inclusion criteria. Using propensity matching we matched two groups of patients who underwent VHR: (1) those with preoperative anemia and (2) those with normal hemoglobin levels. Anemia criteria was set forth by the World Health Organization (WHO).

RESULTS

Univariate analysis did demonstrate statistical significance in post-operative outcomes percentage of serious surgical site infection, poor renal outcomes, transfusion, and unplanned remission in those with preoperative anemia who underwent VHR. In a multivariate analysis, patients who underwent ventral hernia repair with pre-operative anemia had significantly greater odds of unplanned readmission (odds ratio 1.35, 95% confidence interval 1.16-1.57) and serious surgical site infection (odds ratio 1.35, 95% confidence interval 1.04-1.74) independent of known risk factors such as smoking, diabetes and obesity.

CONCLUSIONS

Preoperative anemia is a risk factor for poor postoperative outcomes in those undergoing ventral hernia repair and should be considered when evaluating a patient for repair.

Related Factors of Anemia in Critically Ill Patients: A Prospective Multicenter Study

Anemia is common in critically ill patients; almost 95% of patients admitted to intensive care units (ICUs) have hemoglobin levels below normal. Several causes may explain this phenomenon as well as the tendency to transfuse patients without adequate cause: due to a lack of adherence to protocols, lack of supervision, incomplete transfusion request forms, or a lack of knowledge about the indications, risks, and costs of transfusions. Daily sampling to monitor the coagulation parameters and the acid-base balance can aggravate anemia as the main iatrogenic factor in its production. We studied the association and importance of iatrogenic blood loss and other factors in the incidence of anemia in ICUs. We performed a prospective, observational, multicenter study in five Spanish hospitals. A total of 142 patients with a median age of 58 years (IQI: 48-69), 71.83% male and 28.17% female, were admitted to ICUs without a diagnosis of iatrogenic anemia. During their ICU stay, anemia appeared in 66.90% of the sample, 95 patients, (95% CI: 58.51-74.56%). Risk factors associated with the occurrence of iatrogenic anemia were arterial catheter insertion (72.63% vs. 46.81%, p-value = 0.003), venous catheter insertion (87.37% vs. 72.34%, p-value = 0.023), drainages (33.68% vs. 12. 77%, p-value = 0.038), and ICU stay, where the longer the stay, the higher the rate of iatrogenic anemia (p-value < 0.001). We concluded that there was a statistical significance in the production of iatrogenic anemia due to the daily sampling for laboratory monitoring and critical procedures in intensive care units. The implementation of patient blood management programs could address these issues.

Postoperative variations in anaemia treatment and transfusions (POSTVenTT): protocol for a prospective multicentre observational cohort study of anaemia after major abdominal surgery

AIM

Perioperative anaemia is common and is associated with increased postoperative complications, delayed recovery and increased morbidity and mortality. However, current management of anaemia after surgery is variable. This student- and trainee-led collaborative study aims to audit the postoperative variations in anaemia treatment and transfusions (POSTVenTT) and quantify its impact on patient outcomes after major abdominal surgery.

METHOD

This is the first Australian and Aotearoa New Zealand multicentre study in surgical patients conducted by networks of trainees, students and consultants. Data will be prospectively collected on consecutive adult patients undergoing elective and emergency major abdominal surgery with follow-up to 30 days after hospital discharge. The primary endpoint will be adherence to anaemia management guidelines. Secondary outcomes will include postoperative anaemia, blood transfusion, postoperative complications as per the Clavien-Dindo classification, length of stay and hospital readmission at 30 days.

DISCUSSION

This protocol describes the first Australian and Aotearoa New Zealand collaborative study by medical students and surgical trainees. The collaboration will aim to provide a clear understanding of current practices regarding the management and risk factors for anaemia and association with patient outcomes after major abdominal surgery.

Avoidable Blood Loss in Critical Care and Patient Blood Management: Scoping Review of Diagnostic Blood Loss

BACKGROUND

Anemia remains one of the most common comorbidities in intensive care patients worldwide. The cause of anemia is often multifactorial and triggered by underlying disease, comorbidities, and iatrogenic factors, such as diagnostic phlebotomies. As anemia is associated with a worse outcome, especially in intensive care patients, unnecessary iatrogenic blood loss must be avoided. Therefore, this scoping review addresses the amount of blood loss during routine phlebotomies in adult (>17 years) intensive care patients and whether there are factors that need to be improved in terms of patient blood management (PBM).

METHODS

A systematic search of the Medline Database via PubMed was conducted according to PRISMA guidelines. The reported daily blood volume for diagnostics and other relevant information from eligible studies were charted.

RESULTS

A total of 2167 studies were identified in our search, of which 38 studies met the inclusion criteria (9 interventional studies and 29 observational studies). The majority of the studies were conducted in the US (37%) and Canada (13%). An increasing interest to reduce iatrogenic blood loss has been observed since 2015. Phlebotomized blood volume per patient per day was up to 377 mL. All interventional trials showed that the use of pediatric-sized blood collection tubes can significantly reduce the daily amount of blood drawn.

CONCLUSION

Iatrogenic blood loss for diagnostic purposes contributes significantly to the development and exacerbation of hospital-acquired anemia. Therefore, a comprehensive PBM in intensive care is urgently needed to reduce avoidable blood loss, including blood-sparing techniques, regular advanced training, and small-volume blood collection tubes.

Week-One Anaemia was Associated with Increased One-Year Mortality in Critically Ill Surgical Patients

BACKGROUND

Anaemia has a deleterious effect on surgical patients, but the long-term impact of anaemia in critically ill surgical patients remains unclear.

METHODS

We enrolled consecutive patients who were admitted to surgical intensive care units (ICUs) at a tertiary referral centre in central Taiwan between 2015 and 2020. We used both Cox proportional hazards analysis and propensity score-based analyses, including propensity score matching (PSM), inverse probability of treatment weighting (IPTW), and covariate balancing propensity score (CBPS) to determine hazard ratios (HRs) and 95% confidence intervals (CIs) for one-year mortality.

RESULTS

A total of 7,623 critically ill surgical patients were enrolled, and 29.9% (2,280/7,623) of them had week-one anaemia (haemoglobin <10 g/dL). We found that anaemia was independently associated with an increased risk of one-year mortality after adjustment for relevant covariates (aHR, 1.170; 95% CI, 1.045-1.310). We further identified a consistent strength of association between anaemia and one-year mortality in propensity score-based analyses, with the adjusted HRs in the PSM, IPTW, and CBPS were 1.164 (95% CI 1.025-1.322), 1.179 (95% CI 1.030-1.348), and 1.181 (1.034-1.349), respectively.

CONCLUSIONS

We identified the impact on one-year mortality of anaemia in critically ill surgical patients, and more studies are needed to validate our findings.

Efficacy and Safety of Intravenous Iron Therapy for Treating Anaemia in Critically ill Adults: A Rapid Systematic Review With Meta-Analysis

Our objective was to systematically evaluate the efficacy and safety of intravenous (IV) iron therapy for treating anaemia in critically ill adults (>16 years) admitted to intensive care or high dependency units. We excluded quasi-RCTs and other not truly randomised trials. We searched 7 electronic databases (including CENTRAL, MEDLINE, and Embase) using a pre-defined search strategy from inception to June 14, 2021. One reviewer screened, extracted, and analysed data, with verification by a second reviewer of all decisions. We used Cochrane risk of bias (ROB) 1 and GRADE to assess the certainty of the evidence. We reported 3 comparisons across 1198 patients, in 8 RCTs: (1) IV iron vs control (7 RCTs, 748 participants); our primary outcome (hemoglobin (Hb) concentration at 10 to 30 days) was reported in 7 of the 8 included trials. There was evidence of an effect (very-low certainty) in favour of IV iron over control in the main comparison only (6 RCTs, n = 528, mean difference (MD) 0.52g/dL [95%CI 0.23, 0.81], P = .0005). For the remaining outcomes there was no evidence of an effect in either direction (low certainty of evidence for Hb concentration at <10 days; very-low certainty of evidence for hospital duration, ICU duration, hospital readmission, infection, mortality; HRQoL outcomes were not GRADED). (2) IV iron + subcutaneous erythropoietin (EPO) vs control (2 RCTs, 104 participants); reported outcomes showed no evidence of effect in either direction, based on very-low certainty evidence (Hb concentration at 10-30 days, and <10 days, infection, mortality). (3) Hepcidin-guided treatment with IV iron or iron+ EPO vs standard care (1 RCT, 399 participants) reported evidence of an effect in favour of the intervention for 90-day mortality (low certainty of evidence), but no other group differences for the reported outcomes (low certainty evidence for Hb concentration at 10-30 days, hospital duration; HRQoL was not GRADED). The evidence across all comparisons was downgraded for high and unclear ROB for lack of blinding, incomplete outcome data, baseline imbalance, and imprecision around the estimate (wide CIs and small sample size). In conclusion, the current evidence continues to support further investigation into the role for iron therapy in increasing Hb in critically ill patients. Recent, small, trials have begun to focus on patient-centred outcomes but a large, well conducted, and adequately powered trial is needed to inform clinical practice.

Intravenous iron to treat anaemia following critical care: a multicentre feasibility randomised trial

BACKGROUND

Anaemia is common and associated with poor outcomes in survivors of critical illness. However, the optimal treatment strategy is unclear.

METHODS

We conducted a multicentre, feasibility RCT to compare either a single dose of ferric carboxymaltose 1000 mg i.v. or usual care in patients being discharged from the ICU with moderate or severe anaemia (haemoglobin ≤100 g L^-1). We collected data on feasibility (recruitment, randomisation, follow-up), biological efficacy, and clinical outcomes.

RESULTS

Ninety-eight participants were randomly allocated (49 in each arm). The overall recruitment rate was 34% with 6.5 participants recruited on average per month. Forty-seven of 49 (96%) participants received the intervention. Patient-reported outcome measures were available for 79/93 (85%) survivors at 90 days. Intravenous iron resulted in a higher mean (standard deviation [sd]) haemoglobin at 28 days (119.8 [13.3] vs 106.7 [14.9] g L^-1) and 90 days (130.5 [15.1] vs 122.7 [17.3] g L^-1), adjusted mean difference (10.98 g L^-1; 95% confidence interval [CI], 4.96-17.01; P<0.001) over 90 days after randomisation. Infection rates were similar in both groups. Hospital readmissions at 90 days post-ICU discharge were lower in the i.v. iron group (7/40 vs 15/39; risk ratio=0.46; 95% CI, 0.21-0.99; P=0.037). The median (inter-quartile range) post-ICU hospital stay was shorter in the i.v. iron group but did not reach statistical significance (5.0 [3.0-13.0] vs 9.0 [5.0-16.0] days, P=0.15).

CONCLUSION

A large, multicentre RCT of i.v. iron to treat anaemia in survivors of critical illness appears feasible and is necessary to determine the effects on patient-centred outcomes.

CLINICAL TRIAL REGISTRATION

ISRCTN13721808 (www.isrctn.com).

Patient Blood Management in intensive care patients

PURPOSE OF REVIEW

Patients admitted to ICUs are a heterogeneous group, displaying multiple anaemia risk factors and comorbidities. Clinicians should therefore take all possible measures to identify modifiable risks. Patient Blood Management (PBM) is an approach promoting the timely application of evidence-based interventions designed to maintain patients own blood mass.

RECENT FINDINGS

Within ICU-patients, anaemia is highly prevalent. Generally, anaemia is associated with impaired outcome and need of blood transfusion. Currently, with ICUs working at full capacity and the global blood reserves exhausted, the SARS-CoV-2 pandemic reinforces the need for PBM implementation. For instance, implementation of a comprehensive coagulation management and measures to avoid iatrogenic blood loss may prevent bleeding-associated complications and adherence to blood transfusion guidelines may reduce adverse events associated with transfusion.

SUMMARY

Critically ill patients display various morbidities often requiring individualized treatment. PBM offers patient-centred measures to improve outcome any time during hospital stay.

Anemia during SARS-CoV-2 infection is associated with rehospitalization after viral clearance

Patients with COVID-19 can experience symptoms and complications after viral clearance. It is important to identify clinical features of patients who are likely to experience these prolonged effects. We conducted a retrospective study to compare longitudinal laboratory test measurements (hemoglobin, hematocrit, estimated glomerular filtration rate, serum creatinine, and blood urea nitrogen) in patients rehospitalized after PCR-confirmed SARS-CoV-2 clearance (n = 104) versus patients not rehospitalized after viral clearance (n = 278). Rehospitalized patients had lower median hemoglobin levels in the year prior to COVID-19 diagnosis (Cohen's D = -0.50; p = 1.2 × 10^-3) and during their active SARS-CoV-2 infection (Cohen's D = -0.71; p = 4.6 × 10^-8). Rehospitalized patients were also more likely to be diagnosed with moderate or severe anemia during their active infection (Odds Ratio = 4.07; p = 4.99 × 10^-9). These findings suggest that anemia-related laboratory tests should be considered in risk stratification algorithms for patients with COVID-19.