Lower versus higher hemoglobin threshold for transfusion in septic shock

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members.As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

Patient-important outcomes other than mortality in recent ICU trials: Protocol for a scoping review

BACKGROUND

Randomised clinical trials (RCTs) conducted in intensive care units (ICUs) frequently focus on all-cause mortality, but other patient-important outcomes are increasingly used and recommended. Their use, however, is not straightforward: choices and definitions, operationalisation of death, handling of missing data, choice of effect measures, and statistical analyses for these outcomes vary greatly.

METHODS

We will conduct a scoping review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews. We will search 10 selected general and speciality journals for RCTs conducted in adult ICU patients from 2018 and onwards reporting at least 1 patient-important outcome other than mortality (including days alive without life support/days alive and out of hospital-type outcomes, health-related quality of life, functional/cognitive/neurological outcomes, and other general patient-important outcomes). We will summarise data on outcome measures and definitions, assessment time points, proportions and handling of death, proportions and handling of missing data, and effect measures and statistical methods used for analysis.

DISCUSSION

The outlined scoping review will provide an overview of choices, definitions and handling of patient-important outcomes other than mortality in contemporary RCTs conducted in adult ICU patients. This may guide discussions with patients and relatives, the design of future RCTs, and research on optimal outcome choices and handling.

Impact of Renal Replacement Therapy on Mortality in Critically Ill Patients-The Nephrologist's View within an Interdisciplinary Intensive Care Team

Acute kidney injury (AKI) is a common complication in critically ill patients with an incidence of up to 50% in intensive care patients. The mortality of patients with AKI requiring dialysis in the intensive care unit is up to 50%, especially in the context of sepsis. Different approaches have been undertaken to reduce this high mortality by changing modalities and techniques of renal replacement therapy: an early versus a late start of dialysis, high versus low dialysate flows, intermittent versus continuous dialysis, anticoagulation with citrate or heparin, the use of adsorber or special filters in case of sepsis. Although in smaller studies some of these approaches seemed to have a positive impact on the reduction of mortality, in larger studies these effects could not been reproduced. This raises the question of whether there exists any impact of renal replacement therapy on mortality in critically ill patients—beyond an undeniable impact on uremia, hyperkalemia and/or hypervolemia. Indeed, this is one of the essential challenges of a nephrologist within an interdisciplinary intensive care team: according to the individual situation of a critically ill patient the main indication of dialysis has to be identified and all parameters of dialysis have to be individually chosen with respect to the patient’s situation and targeting the main dialysis indication. Such an interdisciplinary and individual approach would probably be able to reduce mortality in critically ill patients with dialysis requiring AKI.

Severe bleeding in the ICU

PURPOSE OF REVIEW

Severe bleeding events, which require blood transfusions, are a challenge faced by many critical care physicians on a daily basis. Current transfusion guidelines generally recommend rather strict transfusion thresholds and strategies, which can appear opposing to a patient in need for urgent transfusion at first sight. Moreover, applied guidelines are lacking evidence and specificity for the typical ICU patient population and its comorbidities. Transfusion decisions, which are pivotal for clinical outcome, are often unsatisfactorily based on hemoglobin levels only.

RECENT FINDINGS

Recent publications generally support previous studies that a strict transfusion regimen is superior to a liberal one for the majority of cases. Newly developed and easily feasible techniques are currently in clinical trials and have the potential to become a valuable supplementation to hemoglobin-guided decision-making. In addition to the choice of the ideal transfusion strategy, physiological status and comorbidities were found to have a major impact on the outcome of severe bleedings in the ICU.

SUMMARY

The body of evidence for ICU-specific transfusion guidelines is scarce. Critical care physicians should properly evaluate their patient's comorbidities and consider extended point-of-care testing for transfusion decisions in indistinct anemic situations. A strict transfusion strategy should, however, be applied whenever possible.

Low noncarbonic buffer power amplifies acute respiratory acid-base disorders in patients with sepsis: an in vitro study

Patients with sepsis have typically reduced concentrations of hemoglobin and albumin, the major components of noncarbonic buffer power (β). This could expose patients to high pH variations during acid-base disorders. The objective of this study is to compare, in vitro, noncarbonic β of patients with sepsis with that of healthy volunteers, and evaluate its distinct components. Whole blood and isolated plasma of 18 patients with sepsis and 18 controls were equilibrated with different CO₂ mixtures. Blood gases, pH, and electrolytes were measured. Noncarbonic β and noncarbonic β due to variations in strong ion difference (β_SID) were calculated for whole blood. Noncarbonic β and noncarbonic β normalized for albumin concentrations (β_NORM) were calculated for isolated plasma. Representative values at pH = 7.40 were compared. Albumin proteoforms were evaluated via two-dimensional electrophoresis. Hemoglobin and albumin concentrations were significantly lower in patients with sepsis. Patients with sepsis had lower noncarbonic β both of whole blood (22.0 ± 1.9 vs. 31.6 ± 2.1 mmol/L, P < 0.01) and plasma (0.5 ± 1.0 vs. 3.7 ± 0.8 mmol/L, P < 0.01). Noncarbonic β_SID was lower in patients (16.8 ± 1.9 vs. 24.4 ± 1.9 mmol/L, P < 0.01) and strongly correlated with hemoglobin concentration (r = 0.94, P < 0.01). Noncarbonic β_NORM was lower in patients [0.01 (-0.01 to 0.04) vs. 0.08 (0.06-0.09) mmol/g, P < 0.01]. Patients with sepsis and controls showed different amounts of albumin proteoforms. Patients with sepsis are exposed to higher pH variations for any given change in CO₂ due to lower concentrations of noncarbonic buffers and, possibly, an altered buffering function of albumin. In both patients with sepsis and healthy controls, electrolyte shifts are the major buffering mechanism during respiratory acid-base disorders.NEW & NOTEWORTHY Patients with sepsis are poorly protected against acute respiratory acid-base derangements due to a lower noncarbonic buffer power, which is caused both by a reduction in the major noncarbonic buffers, i.e. hemoglobin and albumin, and by a reduced buffering capacity of albumin. Electrolyte shifts from and to the red blood cells determining acute variations in strong ion difference are the major buffering mechanism during acute respiratory acid-base disorders.

Association of fluid balance with mortality in sepsis is modified by admission hemoglobin levels: A large database study

Purpose

Sepsis involves a dysregulated inflammatory response to infection that leads to organ dysfunction. Early fluid resuscitation has been advocated by the Surviving Sepsis Campaign guidelines. However, recent studies have shown that a positive fluid balance is associated with increased mortality in septic patients. We investigated if haemoglobin levels on admission to the intensive care unit (ICU) could modify the association of fluid balance with mortality in patients with sepsis. We hypothesized that with increasing fluid balance, patients with moderate anemia (hemoglobin 7-10g/dL) would have poorer outcomes compared to those without moderate anemia (hemoglobin >10g/dL).

Materials and methods

This retrospective study utilized the Medical Information Mart for Intensive Care-III (MIMIC-III) database. Patients with sepsis, as identified by the International Classification of Diseases, 9th, Clinical Modification codes, were studied. Patients were stratified into those with and without moderate anemia at ICU admission. We investigated the influence of fluid balance measured within 24 hours of ICU admission on 28-day mortality for both patient groups using multivariable logistic regression models. Subgroup and sensitivity analyses were conducted.

Results

8,132 patients (median age 68.6 years, interquartile range 55.1–79.8 years; 52.8% female) were included. Increasing fluid balance (in L) was associated with a significantly decreased risk of 28-day mortality in patients without moderate anemia (OR 0.91, 95%CI 0.84–0.97, p = 0.005, at 6-hour). Conversely, increasing fluid balance was associated with a significantly increased risk of 28-day mortality in patients with moderate anemia (OR 1.05, 95% CI 1.01–1.1, p = 0.022, at 24-hour). Interaction analyses showed that mortality was highest when haemoglobin decreased in patients with moderate anemia who had the most positive fluid balance. Multiple subgroups and sensitivity analyses yielded consistent results.

Conclusions

In septic patients admitted to ICU, admission hemoglobin levels modified the association between fluid balance and mortality and are an important consideration for future fluid therapy trials.

ABO blood types and sepsis mortality

Background

We aimed to determine if the ABO blood types carry different risks of 30-day mortality, acute kidney injury (AKI), and endothelial damage in critically ill patients with sepsis. This was a retrospective cohort study of three independent cohorts of critically ill patients from the United States and Scandinavia consisting of adults with septic shock. We compared the 30-day mortality across the blood types within each cohort and pooled the results in a meta-analysis. We also estimated the incidence of AKI and degree of endothelial damage, as measured by blood concentrations of soluble thrombomodulin and syndecan-1.

Results

We included 12,342 patients with severe sepsis. In a pooled analysis blood type B carried a slightly lower risk of 30-day all-cause mortality compared to non-blood type B (adjusted HR 0.88; 95%-CI 0.79–0.98; p = 0.02). There was no difference in the risk of AKI. Soluble thrombomodulin and syndecan-1 concentrations were lower in patients with blood type B and O compared to blood type A, suggesting less endothelial damage.

Conclusion

Septic patients with blood type B had less endothelial damage, and a small reduction in mortality. The exposure is, however, unmodifiable.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-021-00844-2.

Perioperative Neurological Evaluation and Management to Lower the Risk of Acute Stroke in Patients Undergoing Noncardiac, Nonneurological Surgery: A Scientific Statement From the American Heart Association/American Stroke Association

Perioperative stroke is a potentially devastating complication in patients undergoing noncardiac, nonneurological surgery. This scientific statement summarizes established risk factors for perioperative stroke, preoperative and intraoperative strategies to mitigate the risk of stroke, suggestions for postoperative assessments, and treatment approaches for minimizing permanent neurological dysfunction in patients who experience a perioperative stroke. The first section focuses on preoperative optimization, including the role of preoperative carotid revascularization in patients with high-grade carotid stenosis and delaying surgery in patients with recent strokes. The second section reviews intraoperative strategies to reduce the risk of stroke, focusing on blood pressure control, perioperative goal-directed therapy, blood transfusion, and anesthetic technique. Finally, this statement presents strategies for the evaluation and treatment of patients with suspected postoperative strokes and, in particular, highlights the value of rapid recognition of strokes and the early use of intravenous thrombolysis and mechanical embolectomy in appropriate patients.

Comparison of two delayed strategies for renal replacement therapy initiation for severe acute kidney injury (AKIKI 2): a multicentre, open-label, randomised, controlled trial

BACKGROUND

Delaying renal replacement therapy (RRT) for some time in critically ill patients with severe acute kidney injury and no severe complication is safe and allows optimisation of the use of medical devices. Major uncertainty remains concerning the duration for which RRT can be postponed without risk. Our aim was to test the hypothesis that a more-delayed initiation strategy would result in more RRT-free days, compared with a delayed strategy.

METHODS

This was an unmasked, multicentre, prospective, open-label, randomised, controlled trial done in 39 intensive care units in France. We monitored critically ill patients with severe acute kidney injury (defined as Kidney Disease: Improving Global Outcomes stage 3) until they had oliguria for more than 72 h or a blood urea nitrogen concentration higher than 112 mg/dL. Patients were then randomly assigned (1:1) to either a strategy (delayed strategy) in which RRT was started just after randomisation or to a more-delayed strategy. With the more-delayed strategy, RRT initiation was postponed until mandatory indication (noticeable hyperkalaemia or metabolic acidosis or pulmonary oedema) or until blood urea nitrogen concentration reached 140 mg/dL. The primary outcome was the number of days alive and free of RRT between randomisation and day 28 and was done in the intention-to-treat population. The study is registered with ClinicalTrial.gov, NCT03396757 and is completed.

FINDINGS

Between May 7, 2018, and Oct 11, 2019, of 5336 patients assessed, 278 patients underwent randomisation; 137 were assigned to the delayed strategy and 141 to the more-delayed strategy. The number of complications potentially related to acute kidney injury or to RRT were similar between groups. The median number of RRT-free days was 12 days (IQR 0-25) in the delayed strategy and 10 days (IQR 0-24) in the more-delayed strategy (p=0·93). In a multivariable analysis, the hazard ratio for death at 60 days was 1·65 (95% CI 1·09-2·50, p=0·018) with the more-delayed versus the delayed strategy. The number of complications potentially related to acute kidney injury or renal replacement therapy did not differ between groups.

INTERPRETATION

In severe acute kidney injury patients with oliguria for more than 72 h or blood urea nitrogen concentration higher than 112 mg/dL and no severe complication that would mandate immediate RRT, longer postponing of RRT initiation did not confer additional benefit and was associated with potential harm.

FUNDING

Programme Hospitalier de Recherche Clinique.

A Systematic Literature Review of Packed Red Cell Transfusion Usage in Adult Extracorporeal Membrane Oxygenation

Background: Blood product administration plays a major role in the management of patients treated with extracorporeal membrane oxygenation (ECMO) and may be a contributor to morbidity and mortality. Methods: We performed a systematic review of the published literature to determine the current usage of packed red cell transfusions. Predefined search criteria were used to identify journal articles reporting transfusion practice in ECMO by interrogating EMBASE and Medline databases and following the PRISMA statement. Results: Out of 1579 abstracts screened, articles reporting ECMO usage in a minimum of 10 adult patients were included. Full texts of 331 articles were obtained, and 54 were included in the final analysis. All studies were observational (2 were designed prospectively, and two were multicentre). A total of 3808 patients were reported (range 10–517). Mean exposure to ECMO was 8.2 days (95% confidence interval (CI) 7.0–9.4). A median of 5.6% was not transfused (interquartile range (IQR) 0–11.3%, 19 studies). The mean red cell transfusion per ECMO run was 17.7 units (CI 14.2–21.2, from 52 studies) or 2.60 units per day (CI 1.93–3.27, from 49 studies). The median survival to discharge was 50.8% (IQR 40.0–64.9%). Conclusion: Current evidence on transfusion practice in ECMO is mainly drawn from single-centre observational trials and varies widely. The need for transfusions is highly variable. Confounding factors influencing transfusion practice need to be identified in prospective multicentre studies to mitigate potential harmful effects and generate hypotheses for interventional trials.

Adherence to blood product transfusion guidelines-An observational study of the current transfusion practice in a medical intensive care unit

BACKGROUND

Blood transfusions though life-saving are not entirely benign. They are the most overused procedure in the hospital and have been under scrutiny by the 'Choosing Wisely campaign'. The strict adoption of restrictive transfusion guidelines could improve patient outcomes while reducing cost.

OBJECTIVES

In this study, we evaluate adherence to restrictive transfusion guidelines, along with hospital mortality and length of stay (LOS) in transfusion events with a pre-transfusion haemoglobin (Hb) ≥7 g/dl. Additionally, we evaluated associated costs accrued due to unnecessary transfusions.

METHODS

We conducted a retrospective observational study in a 64-bed medical intensive care unit (MICU) of an academic medical centre involving all adult patients (N = 957) requiring packed red blood cell transfusion between January 2015 and December 2015.

RESULTS

In total, 3140 units were transfused with a mean pre-transfusion Hb of 6.75 ± 0.86 g/dl. Nine hundred forty-four (30%) transfusion events occurred with a pre-transfusion Hb ≥7 g/dl, and 385 (12.3%) of these occurred in patients without hypotension, tachycardia, use of vasopressors, or coronary artery disease. Forgoing them could have led to a savings of approximately 0.3 million dollars. Transfusion events with pre-transfusion Hb ≥7 g/dl were associated with an increased mortality in patients with acute blood loss (odds ratio [OR] 2.08, 95% confidence interval [CI] 1.11-3.88; p = 0.02) and LOS in patients with chronic blood loss (β₁ .8.26, 95% CI 4.09-12.43; p < 0.01).

CONCLUSION

A subset of anaemic patients in the MICU still receive red blood cell transfusions against restrictive guidelines offering hospitals the potential for effective intervention that has both economic and clinical implications.

Resuscitation of the Critically Ill Older Adult

In 30 years, adults 65 and older will represent 20% of the US population, with increased medical comorbidities leading to higher rates of critical illness and mortality. Despite significant acute illness, presenting symptoms and vital sign abnormalities may be subtle. Resuscitative guidelines are a helpful starting point but appropriate diagnostics, bedside ultrasound, and frequent reassessments are needed to avoid procrustean care that may worsen outcomes. Baseline functional status is as important as underlying comorbid conditions when prognosticating, and the patient's personal wishes should be sought early and throughout care with clear communication regarding prospects for immediate survival and overall recovery.

Association of perioperative red blood cell transfusions with all-cause and cancer-specific death in patients undergoing surgery for gastrointestinal cancer: Long-term outcomes from a population-based cohort

BACKGROUND

Red blood cell transfusions are common in patients undergoing gastrointestinal cancer surgery. Yet, to adequately balance their risks and benefits, clinicians must understand how transfusions may affect long-term outcomes. We aimed to determine if perioperative red blood cell transfusions are associated with a higher risk of all-cause and cancer-specific death among patients who underwent gastrointestinal cancer resection.

METHOD

We identified a population-based cohort of patients who underwent gastrointestinal cancer resection in Ontario, Canada (2007-2019). All-cause death was compared between transfused and nontransfused patients using Cox proportional hazards regression, while cancer-specific death was compared with competing risk regression.

RESULT

A total of 74,962 patients (mean age, 67.7 years; 55.4% male; 79.7% colorectal cancer) had gastrointestinal cancer surgery during the study period; 20.8% received perioperative red blood cell transfusions. Patients who received red blood cell transfusions had increased hazards of all-cause and cancer-specific death relative to patients who did not (hazard ratio: 1.39, 95% confidence interval 1.34-1.44; cause-specific hazard ratio: 1.36, 1.30-1.43). The adjusted risk of all-cause death was higher in early follow-up intervals (3-6 months postoperatively) but remained elevated in each interval over 5 years. The association persisted after restricting to patients without postoperative complications or bleeding and was robust to unmeasured confounding.

CONCLUSION

Red blood cell transfusion among patients with gastrointestinal cancer is associated with increased all-cause death. This was observed long beyond the immediate postoperative period and independent of short-term postoperative morbidity and mortality. These findings should help clinicians balance the risks and benefits of transfusion before well-designed trials are conducted in this patient population.

An automated approach to determine antibody endpoint titers for COVID-19 by an enzyme-linked immunosorbent assay

While a variety of therapeutic options continue to emerge for COVID-19 treatment, convalescent plasma (CP) has been used as a possible treatment option early in the pandemic. One of the most significant challenges with CP therapy, however, both when defining its efficacy and implementing its approach clinically, is accurately and efficiently characterizing an otherwise heterogenous therapeutic treatment. Given current limitations, our goal is to leverage a SARS antibody testing platform with a newly developed automated endpoint titer analysis program to rapidly define SARS-CoV-2 antibody levels in CP donors and hospitalized patients. A newly developed antibody detection platform was used to perform a serial dilution enzyme-linked immunosorbent assay (ELISA) for immunoglobulin (Ig)G, IgM, and IgA SARS-CoV-2 antibodies. Data were then analyzed using commercially available software, GraphPad Prism, or a newly developed program developed in Python called TiterScape, to analyze endpoint titers. Endpoint titer calculations and analysis times were then compared between the two analysis approaches. Serial dilution analysis of SARS-CoV-2 antibody levels revealed a high level of heterogeneity between individuals. Commercial platform analysis required significant time for manual data input and extrapolated endpoint titer values when the last serial dilution was above the endpoint cutoff, occasionally producing erroneously high results. By contrast, TiterScape processed 1008 samples for endpoint titer results in roughly 14 minutes compared with the 8 hours required for the commercial software program analysis. Equally important, results generated by TiterScape and Prism were highly similar, with differences averaging 1.26 ± 0.2 percent (mean ± SD). The pandemic has created unprecedented challenges when seeking to accurately test large numbers of individuals for SARS-CoV-2 antibody levels with a rapid turnaround time. ELISA platforms capable of serial dilution analysis coupled with a highly flexible software interface may provide a useful tool when seeking to define endpoint titers in a high-throughput manner. Immunohematology 2021;37:33-43.

While a variety of therapeutic options continue to emerge for COVID-19 treatment, convalescent plasma (CP) has been used as a possible treatment option early in the pandemic. One of the most significant challenges with CP therapy, however, both when defining its efficacy and implementing its approach clinically, is accurately and efficiently characterizing an otherwise heterogenous therapeutic treatment. Given current limitations, our goal is to leverage a SARS antibody testing platform with a newly developed automated endpoint titer analysis program to rapidly define SARS-CoV-2 antibody levels in CP donors and hospitalized patients. A newly developed antibody detection platform was used to perform a serial dilution enzyme-linked immunosorbent assay (ELISA) for immunoglobulin (Ig)G, IgM, and IgA SARS-CoV-2 antibodies. Data were then analyzed using commercially available software, GraphPad Prism, or a newly developed program developed in Python called TiterScape, to analyze endpoint titers. Endpoint titer calculations and analysis times were then compared between the two analysis approaches. Serial dilution analysis of SARS-CoV-2 antibody levels revealed a high level of heterogeneity between individuals. Commercial platform analysis required significant time for manual data input and extrapolated endpoint titer values when the last serial dilution was above the endpoint cutoff, occasionally producing erroneously high results. By contrast, TiterScape processed 1008 samples for endpoint titer results in roughly 14 minutes compared with the 8 hours required for the commercial software program analysis. Equally important, results generated by TiterScape and Prism were highly similar, with differences averaging 1.26 ± 0.2 percent (mean ± SD). The pandemic has created unprecedented challenges when seeking to accurately test large numbers of individuals for SARS-CoV-2 antibody levels with a rapid turnaround time. ELISA platforms capable of serial dilution analysis coupled with a highly flexible software interface may provide a useful tool when seeking to define endpoint titers in a high-throughput manner. Immunohematology 2021;37:33–43.

Effect of low vs high haemoglobin transfusion trigger on cardiac output in patients undergoing elective vascular surgery: Post-hoc analysis of a randomized trial

BACKGROUND

During vascular surgery, restricted red-cell transfusion reduces frontal lobe oxygen (ScO₂ ) saturation as determined by near-infrared spectroscopy. We evaluated whether inadequate increase in cardiac output (CO) following haemodilution explains reduction in ScO₂ .

METHODS

This is a post-hoc analysis of data from the Transfusion in Vascular surgery (TV) Trial where patients were randomized on haemoglobin drop below 9.7 g/dL to red-cell transfusion at haemoglobin below 8.0 (low-trigger) vs 9.7 g/dL (high-trigger). Fluid administration was guided by optimizing stroke volume. We compared mean intraoperative levels of CO, haemoglobin, oxygen delivery, and CO at nadir ScO₂ with linear regression adjusted for age, operation type and baseline. Data for 46 patients randomized before end of surgery were included for analysis.

RESULTS

The low-trigger resulted in a 7.1% lower mean intraoperative haemoglobin level (mean difference, -0.74 g/dL; P < .001) and reduced volume of red-cell transfused (median [inter-quartile range], 0 [0-300] vs 450 mL [300-675]; P < .001) compared with the high-trigger group. Mean CO during surgery was numerically 7.3% higher in the low-trigger compared with the high-trigger group (mean difference, 0.36 L/min; 95% confidence interval (CI.95), -0.05 to 0.78; P = .092; n = 42). At the nadir ScO₂ -level, CO was 11.9% higher in the low-trigger group (mean difference, 0.58 L/min; CI.95, 0.10-1.07; P = .024). No difference in oxygen delivery was detected between trial groups (MD, 1.39 dL_O2 /min; CI.95, -6.16 to 8.93; P = .721).

CONCLUSION

Vascular surgical patients exposed to restrictive RBC transfusion elicit the expected increase in CO making it unlikely that their potentially limited cardiac capacity explains the associated ScO₂ decrease.

Transfusion in Pediatric Patients: Review of Evidence-Based Guidelines

Children require transfusion of blood components for a vast array of medical conditions, including acute hemorrhage, hematologic and nonhematologic malignancies, hemoglobinopathy, and allogeneic and autologous stem cell transplant. Evidence-based literature on pediatric transfusion practices is limited, particularly for non-red blood cell products, and many recommendations are extrapolated from studies in adult populations. Recognition of these knowledge gaps has led to increasing numbers of clinical trials focusing on children and establishment of pediatric transfusion working groups in recent years. This article reviews existing literature on pediatric transfusion therapy within the larger context of analogous data in adult populations.

Novel approach to an early assessment of a patient's potential for neurological remission after acute spinal cord injury: Analysis of hemoglobin concentration dynamics

Context/objective: Examining hemoglobin (Hb) dynamics with regard to the potential of neurological remission in patients with traumatic spinal cord injury (TSCI).Design: Prospective Clinical Observational Study.Setting: BG Trauma Centre Ludwigshafen, Department of Paraplegiology, Rhineland-Palatinate, Germany.Methods: From 2011 to 2017 a total of 80 patients with acute spinal injury were enrolled and divided into three groups: initial neurological impairment either with (G1; n = 33) or without subsequent neurological remission (G0; n = 35) and vertebral fractures without initial neurological impairment as control group (C; n = 12). Blood samples were taken for 3 months at 11 time-points after injury. Analyses were performed using routine diagnostics.Outcome measures: Multiple logistic regression was used to determine the prognostic value of Hb regarding neurological remission respecting clinical covariates.Results: Data showed elevated mean Hb concentrations in G1 from the third day to 1 month compared to G0, Hb levels were significantly higher in G1 after 3 days (P = 0.03, G1 > G0). The final multiple logistic regression model based on this data predicting the presence of neurological remission resulted in an AUC (area under the curve) of 80.5% (CI: 67.8%-93.2%) in the ROC (receiver operating characteristic) analysis.Conclusion: Elevated Hb concentrations are associated with a higher likelihood of neurological remission. Elevated concentrations of Hb in G1 compared to G0 over time might be linked to both a better initial oxygen supply response and a decreased ECM (extracellular matrix) degradation highlighting the role of Hb as a valuable biomarker for neural regeneration after TSCI.

Extracorporeal Gas Exchange for Acute Respiratory Distress Syndrome: Open Questions, Controversies and Future Directions

Veno-venous extracorporeal membrane oxygenation (V-V ECMO) in acute respiratory distress syndrome (ARDS) improves gas exchange and allows lung rest, thus minimizing ventilation-induced lung injury. In the last forty years, a major technological and clinical improvement allowed to dramatically improve the outcome of patients treated with V-V ECMO. However, many aspects of the care of patients on V-V ECMO remain debated. In this review, we will focus on main issues and controversies on caring of ARDS patients on V-V ECMO support. Particularly, the indications to V-V ECMO and the feasibility of a less invasive extracorporeal carbon dioxide removal will be discussed. Moreover, the controversies on management of mechanical ventilation, prone position and sedation will be explored. In conclusion, we will discuss evidences on transfusions and management of anticoagulation, also focusing on patients who undergo simultaneous treatment with ECMO and renal replacement therapy. This review aims to discuss all these clinical aspects with an eye on future directions and perspectives.

Fluid Therapy in Dogs and Cats With Sepsis

Sepsis is currently defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis may occur secondary to infection anywhere in the body, and its pathogenesis is complex and not yet fully understood. Variations in the host immune response result in diverse clinical manifestations, which complicates clinical recognition and fluid therapy both in humans and veterinary species. Septic shock is a subset of sepsis in which particularly profound circulatory, cellular, and metabolic abnormalities are associated with a greater risk of mortality than with sepsis alone. Although septic shock is a form of distributive shock, septic patients frequently present with hypovolemic and cardiogenic shock as well, further complicating fluid therapy decisions. The goals of this review are to discuss the clinical recognition of sepsis in dogs and cats, the basic mechanisms of its pathogenesis as it affects hemodynamic function, and considerations for fluid therapy. Important pathophysiologic changes, such as cellular interaction, microvascular alterations, damage to the endothelial glycocalyx, hypoalbuminemia, and immune paralysis will be also reviewed. The advantages and disadvantages of treatment with crystalloids, natural and synthetic colloids, and blood products will be discussed. Current recommendations for evaluating fluid responsiveness and the timing of vasopressor therapy will also be considered. Where available, the veterinary literature will be used to guide recommendations.

Impact of body weight on hemoglobin increments in adult red blood cell transfusion

BACKGROUND

Though weight is a major consideration when transfusing blood in pediatric patients, it is generally not considered when dosing transfusions in adults. We hypothesized that the change in hemoglobin (Hb) concentration is inversely proportional to body weight when transfusing red blood cells (RBC) in adults.

METHODS

A total of 13,620 adult surgical patients at our institution were assessed in this retrospective cohort study (2009-2016). Patients were stratified based on total body weight (kg): 40-59.9 (16.6%), 60-79.9 (40.4%), 80-99.9 (28.8%), 100-119.9 (11.3%), and 120-139.9 (2.9%). The primary outcome was the change in Hb per RBC unit transfused. Subgroup analyses were performed after stratification by sex (male/female) and the total number of RBC units received (1/2/≥3 units). Multivariable models were used to assess the association between weight and change in Hb.

RESULTS

As patients' body weight increased, there was a decrease in the mean change in Hb per RBC unit transfused (40-59.9 kg: 0.85 g/dL, 60-79.9 kg: 0.73 g/dL, 80-99.9 kg: 0.66 g/dL, 100-119.9 kg: 0.60 g/dL, 120-139.9 kg: 0.55 g/dL; p < .0001). This corresponded with a 35% difference in the change in Hb between the lowest and highest weight categories on univariate analysis. Similar trends were seen after subgroup stratification. On multivariable analysis, for every 20 kg increase in patient weight, there was a ~6.5% decrease in the change in Hb per RBC unit transfused (p < .0001).

CONCLUSIONS

Patient body weight differentially impacts the change in Hb after RBC transfusion. These findings justify incorporating body weight into the clinical decision-making process when transfusing blood in adult surgical patients.

Impact of Blood Product Transfusions on the Risk of ICU-Acquired Infections in Septic Shock

OBJECTIVES

Transfusions of blood products are common in critically ill patients and have a potential for immunomodulation. The aim of this study is to address the impact of transfusion of blood products on the susceptibility to ICU-acquired infections in the high-risk patients with septic shock.

DESIGN

A single-center retrospective study over a 10-year period (2008-2017).

SETTING

A medical ICU of a tertiary-care center.

PATIENTS

All consecutive patients diagnosed for septic shock within the first 48 hours of ICU admission were included. Patients who were discharged or died within the first 48 hours were excluded.

INTERVENTIONS

RBC, platelet, and fresh frozen plasma transfusions collected up to 24 hours prior to the onset of ICU-acquired infection.

MEASUREMENTS AND MAIN RESULTS

During the study period, 1,152 patients were admitted for septic shock, with 893 patients remaining alive in the ICU after 48 hours of management. A first episode of ICU-acquired infection occurred in 28.3% of the 48-hour survivors, with a predominance of pulmonary infections (57%). Patients with ICU-acquired infections were more likely to have received RBC, platelet, and fresh frozen plasma transfusions. In a multivariate Cox cause-specific analysis, transfusions of platelets (cause-specific hazard ratio = 1.55 [1.09-2.20]; p = 0.01) and fresh frozen plasma (cause-specific hazard ratio = 1.38 [0.98-1.92]; p = 0.05) were independently associated with the further occurrence of ICU-acquired infections.

CONCLUSIONS

Transfusions of platelets and fresh frozen plasma account for risk factors of ICU-acquired infections in patients recovering from septic shock. The occurrence of ICU-acquired infections should be considered as a relevant endpoint in future studies addressing the indications of transfusions in critically ill patients.

Erstellung zuverlässiger Erythrozytenkonzentrat-Bedarfslisten für Operationen und Interventionen aus Data-Warehouse-Daten und der patientenbezogenen Chargendokumentation von Blutkomponenten

Das Versäumnis, transfusionsvorbereitende Diagnostik durchzuführen und eine ausreichende Anzahl von Blutkomponenten vor der Operation zu bestellen, führt zunehmend zu klinischen Notfällen und vermeidbaren Risiken für die Patienten. Die eigentlich obligatorische Erstellung von Blutbedarfslisten scheitert oft an der Verfügbarkeit geeigneter Daten. Das Universitätsklinikum Erlangen ist ein Krankenhaus der Tertiärversorgung mit 1400 Betten. Hier werden seit 2010 kontinuierlich alle relevanten Daten zur Interpretation von Mustern bei der Verwendung von Blutbestandteilen erhoben. Wir sind in der Lage, die klinischen Data-Warehouse-Komponenten der persönlichen Daten der Empfänger von Erythrozytenkonzentraten (EK), die Codes der stationären Patienten im G-DRG-System (G-DRG: German Diagnosis Related Group), ICD-Codes, OPS-Codes und die Daten der EK-Komponenten aus dem IT-System der Blutbank zu integrieren. Die erhaltenen DRGs, ICD-Codes und OPS-Codes werden mit den Daten des Blutkomponentenverbrauchs auf individueller Basis verknüpft. Analysen können sowohl im gesamten Krankenhaus als auch in Bezug auf bestimmte Abteilungen durchgeführt werden. Die laufende Verfeinerung der Datenbankabfragen verbessert die Fähigkeit, den Blutbedarf für Standardoperationen und Interventionen korrekt abzuschätzen. Die Ergebnisse weichen zum Teil erheblich von den Schätzungen der Operateure hinsichtlich der Wahrscheinlichkeit einer Transfusion ab, oftmals wird die Wahrscheinlichkeit einer Transfusion unterschätzt. Die korrekte Einhaltung der 10-prozentigen Transfusionswahrscheinlichkeitsgrenze für die Frage der frühen präoperativen Bereitstellung von Kreuzblut kann durch solche Abfragen verbessert werden. Dem Phänomen der „verzögerten Transfusion“ entgegenzuwirken, wird zu einer immer wichtigeren Aufgabe für den klinisch tätigen transfusionsmedizinischen Arzt. Die Erstellung von Statistiken über die Transfusionswahrscheinlichkeit durch die Verknüpfung von Data-Warehouse-Daten und Chargendokumentationsdaten aus Blutbanken kann die notwendigen Werkzeuge bereitstellen.

Rationale Therapie mit Erythrozytenkonzentraten – Update 2020

Der Einsatz von Erythrozytenkonzentraten muss dem Gebot einer rationalen Indikation folgen. Um dies weiter zu gewährleisten, wurden die 2009 publizierten und zuletzt 2014 in Teilen revidierten „Querschnitts-Leitlinien zur Therapie mit Blutkomponenten und Plasmaderivaten“ 1 der Bundesärztekammer 2020 einer systematischen Novellierung unterzogen. Der Artikel stellt sie vor.

Evaluation of a novel Cardiac Peri-Operative Transfusion Trigger Scoring system in patients with coronary artery disease

BACKGROUND

A simple and accurate scoring system to guide perioperative blood transfusion in patients with coronary artery disease (CAD) undergoing cardiac surgery is lacking. The trigger point for blood transfusions for these patients may be different from existing transfusion guidelines. This study aimed to evaluate the safety and efficacy of a new scoring strategy for use in guiding transfusion decisions in patients with CAD.

METHODS

A multicenter randomized controlled trial was conducted at three third-level grade-A hospitals from January 2015 to May 2018. Data of 254 patients in a Cardiac Peri-Operative Transfusion Trigger Score (cPOTTS) group and 246 patients in a group receiving conventional evaluation of the need for transfusion (conventional group) were analysed. The requirements for transfusion and the per capita consumption of red blood cells (RBCs) were compared between groups.

RESULTS

Baseline characteristics of the two groups were comparable. Logistic regression analyses revealed no significant differences between the two groups in primary outcomes (1-year mortality and perioperative ischemic cardiac events), secondary outcomes (shock, infections, and renal impairment), ICU admission, and ICU stay duration. However, patients in the cPOTTS group had significantly shorter hospital stays, lower hospital costs, lower utilization rate and lower per capita consumption of transfused RBCs than controls. Stratified analyses revealed no significant differences between groups in associations between baseline characteristics and perioperative ischemic cardiac events, except for hemofiltration or dialysis and NYHA class in I.

CONCLUSIONS

This novel scoring system offered a practical and straightforward guideline of perioperative blood transfusion in patients with CAD. Trial registration chiCTR1800016561(2017/7/19).

Mortality and Transfusion Requirements in COVID-19 Hospitalized Italian Patients According to Severity of the Disease

There is paucity of data on the transfusion need and its impact on the overall mortality in patients with COVID-19. We explored mortality in hospitalized patients with COVID-19 who required transfusions. Information on clinical variables and in-hospital mortality were obtained from medical records of 422 patients admitted to medical wards or the Intensive Care Unit (ICU). In-hospital mortality occurred in 147 (34.8%) patients, 94 (63.9%) of whom were admitted to the ICU. The median fatalities age was 77 years (IQR 14). Overall, 100 patients (60 males) received transfusion during hospitalization. The overall mortality was significantly and independently associated with age, ICU admission, Chronic Kidney Disease (CKD), and the number of transfused Red Blood Cell (RBC) units. Specifically, CKD was associated with mortality in patients admitted to medical wards, whereas the number of transfused RBC units predicted mortality in those admitted to the ICU. Transfusion strongly interacted with the admission to ICU (OR: 9.9; 95% CI: 2.5–40.0). In patients with COVID-19, age is one of the strongest risk factors in predicting mortality independently of the disease’s severity. CKD confers a higher risk of mortality in patients admitted to medical wards. In those admitted to the ICU, the more RBC units are transfused, the more mortality increases.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

Impact of red blood cell transfusion on oxygen transport and metabolism in patients with sepsis and septic shock: a systematic review and meta-analysis

Red blood cell transfusion is thought to improve cell respiration during septic shock. Nevertheless, its acute impact on oxygen transport and metabolism in this condition remains highly debatable. The objective of this study was to evaluate the impact of red blood cell transfusion on microcirculation and oxygen metabolism in patients with sepsis and septic shock. We conducted a search in the MEDLINE®, Elsevier and Scopus databases. We included studies conducted in adult humans with sepsis and septic shock. A systematic review and meta-analysis were performed using the DerSimonian and Laird random-effects model. A p value < 0.05 was considered significant. Nineteen manuscripts with 428 patients were included in the analysis. Red blood cell transfusions were associated with an increase in the pooled mean venous oxygen saturation of 3.7% (p < 0.001), a decrease in oxygen extraction ratio of -6.98 (p < 0.001) and had no significant effect on the cardiac index (0.02L/minute; p = 0,96). Similar results were obtained in studies including simultaneous measurements of venous oxygen saturation, oxygen extraction ratio, and cardiac index. Red blood cell transfusions led to a significant increase in the proportion of perfused small vessels (2.85%; p = 0.553), while tissue oxygenation parameters revealed a significant increase in the tissue hemoglobin index (1.66; p = 0.018). Individual studies reported significant improvements in tissue oxygenation and sublingual microcirculatory parameters in patients with deranged microcirculation at baseline. Red blood cell transfusions seemed to improve systemic oxygen metabolism with apparent independence from cardiac index variations. Some beneficial effects have been observed for tissue oxygenation and microcirculation parameters, particularly in patients with more severe alterations at baseline. More studies are necessary to evaluate their clinical impact and to individualize transfusion decisions.

Venoarterial extra corporeal membrane oxygenation and blood component usage in pediatric patients undergoing cardiac surgery: Single centre experience

Background

Extra Corporeal Membrane Oxygenation (ECMO) is a well-known tool for providing life-saving support in patients developing post cardiotomy cardiogenic shock in post cardiac surgeries. The current study was designed to evaluate blood transfusion requirements and its relation to mortality in neonate and pediatric cardiac patients requiring venoarterial cardiac ECMO during post-operative period following cardiac surgery.

Materials and Methods

Overall 24 pediatric patients (including neonates) who underwent VA ECMO in post cardiac surgery at our institute from January 2016 to October 2017 were included in the study. The details of demographics, blood transfusion, ECMO, and morbidity and mortality were collected for all the patients.

Objective of the Study

The primary objective of our study was to assess the outcome of patients on ECMO in post pediatric cardiac surgery. The secondary objective of the study was to assess the effect of blood transfusion on the outcome of the patients.

Results

Overall mortality rate was 50% (n = 12). The overall transfusion rate of packed red blood cells was higher in patients who did not survive even after institution of VA ECMO. The transfusion of other blood products like platelets, cryoprecipitate, and fresh frozen plasma were also higher in this group of patients though it was statistically non-significant except for packed red cell transfusion. Though statistically non-significant, the patients who didn't survive even after institution of VA ECMO post-surgery had relatively higher mean age (703.88 ± 998.94 days) as compared to their counterparts (510.63 ± 384.36 days).

Conclusion

The use of ECMO is associated with considerable morbidity and mortality. Packed red cell transfusion is definitely higher in expired patients, indicative of deteriorated status of the patient. However, considering non-significant association of other blood components, except packed red cell it is recommended that patients' overall clinical condition should be taken into consideration for transfusion of blood products and not only targeting the transfusion triggers.

Effects of red blood cell transfusions given to non-septic critically ill patients: a propensity score matched study

INTRODUCTION

Previous studies have demonstrated that low-grade red blood cell transfusions (RBC) given to septic patients are harmful. The objectives of the present study were to compare mortality and morbidity in non-septic critically ill patients who were given low-grade RBC transfusions at haemoglobin level > 70 γ L-1 with patients without RBC-transfusions any of the first 5 days in intensive care.

MATERIAL AND METHODS

Adult patients admitted to a general intensive care unit between 2007 and 2018 at a university hospital were eligible for inclusion. Patients who received > 2 units RBC transfusion per day during the first 5 days after admisasion, with pre-transfusion haemoglobin level < 70 γ L-1 or with severe sepsis or septic shock, were excluded.

RESULTS

In total, 9491 admissions were recorded during the study period. Propensity score matching resulted in 2 well matched groups with 674 unique patients in each. Median pre-transfusion haemoglobin was 98 γ L-1 (interquartile range 91-107 γ L-1). Mortality was higher in the RBC group with an absolute risk increase for death at 180 days of 5.9% (95% CI: 3.6-8.3; P < 0.001). Low-grade RBC-transfusion was also associated with renal, circulatory, and respiratory failure as well as a higher SOFA-max score. Sensitivity analyses suggested that disease trajectories during the exposure time did not significantly differ between the groups.

CONCLUSIONS

Low-grade RBC-transfusions given to non-septic critically ill patients without significant anaemia were associated with increased mortality, increased kidney, circulatory, and respiratory failure, as well as higher SOFA-max score.

Defining postoperative transfusion thresholds in liver transplant recipients: A novel retrospective approach

BACKGROUND

The optimal transfusion threshold for most patient populations has been defined as hematocrit (HCT) <21%. However, some specific patient populations are known to benefit from higher transfusion thresholds. To date, the optimal postoperative transfusion threshold for patients undergoing liver transplant has not been determined. To define the ideal transfusion threshold for liver transplant patients, we designed a retrospective study of 496 liver transplant recipients.

METHODS

Using HCT prior to discharge as a surrogate marker for transfusion thresholds we grouped patients into three groups of transfusion thresholds (HCT <21%, <24%, and >30%). Transfusion rates (intra- and postoperative), graft and patient survival, and complications requiring readmission were compared between groups.

RESULTS

Ninety-two percent of patients were transfused during their hospital stay. Graft survival, patient survival, and rates of readmission within 30 days of discharge were no different between the three discharge HCT groups. Patients discharged with HCT >30% were less likely to be readmitted with infectious complications; however, this group also had the lowest model of end-stage liver (MELD) score at time of transplantation and were less likely to have received a transfusion during their hospital stay.

CONCLUSION

Transfusion thresholds of HCT <24%, and potentially as low as 21% are acceptable in postoperative liver transplant recipients. The conduct of a randomized clinical trial, as supported by these data, will be necessary to support the use of lower thresholds.

Anemia at Intensive Care Unit Admission and Hospital Mortality Among Patients at a Referral Hospital in Malawi

BACKGROUND

Anemia is associated with intensive care unit (ICU) outcomes, but data describing this association in sub-Saharan Africa are scarce. Patients in this region are at risk for anemia due to endemic conditions like malaria and because transfusion services are limited.

METHODS

This was a prospective cohort study of ICU patients at Kamuzu Central Hospital (KCH) in Malawi. Exclusion criteria included age <5 years, pregnancy, ICU readmission, or admission for head injury. Cumulative incidence functions and Fine-Gray competing risk models were used to evaluate hemoglobin (Hgb) at ICU admission and hospital mortality.

RESULTS

Of 499 patients admitted to ICU, 359 were included. The median age was 28 years (interquartile ranges (IQRs) 20-40) and 37.5% were men. Median Hgb at ICU admission was 9.9 g/dL (IQR 7.5-11.4 g/dL; range 1.8-18.1 g/dL). There were 61 (19%) patients with Hgb < 7.0 g/dL, 59 (19%) with Hgb 7.0-8.9 g/dL, and 195 (62%) with Hgb ≥ 9.0 g/dL. Hospital mortality was 51%, 59%, and 54%, respectively. In adjusted analyses, anemia was associated with hospital mortality but was not statistically significant.

CONCLUSIONS

This study provides preliminary evidence that anemia at ICU admission may be an independent predictor of hospital mortality in Malawi. Larger studies are needed to confirm this association.

Lower versus higher hemoglobin threshold for transfusion in ARDS patients with and without ECMO

BACKGROUND

Efficacy and safety of different hemoglobin thresholds for transfusion of red blood cells (RBCs) in adults with an acute respiratory distress syndrome (ARDS) are unknown. We therefore assessed the effect of two transfusion thresholds on short-term outcome in patients with ARDS.

METHODS

Patients who received transfusions of RBCs were identified from a cohort of 1044 ARDS patients. After propensity score matching, patients transfused at a hemoglobin concentration of 8 g/dl or less (lower-threshold) were compared to patients transfused at a hemoglobin concentration of 10 g/dl or less (higher-threshold). The primary endpoint was 28-day mortality. Secondary endpoints included ECMO-free, ventilator-free, sedation-free, and organ dysfunction-free composites.

MEASUREMENTS AND MAIN RESULTS

One hundred ninety-two patients were eligible for analysis of the matched cohort. Patients in the lower-threshold group had similar baseline characteristics and hemoglobin levels at ARDS onset but received fewer RBC units and had lower hemoglobin levels compared with the higher-threshold group during the course on the ICU (9.1 [IQR, 8.7-9.7] vs. 10.4 [10-11] g/dl, P < 0.001). There was no difference in 28-day mortality between the lower-threshold group compared with the higher-threshold group (hazard ratio, 0.94 [95%-CI, 0.59-1.48], P = 0.78). Within 28 days, 36.5% (95%-CI, 27.0-46.9) of the patients in the lower-threshold group compared with 39.5% (29.9-50.1) of the patients in the higher-threshold group had died. While there were no differences in ECMO-free, sedation-free, and organ dysfunction-free composites, the chance for successful weaning from mechanical ventilation within 28 days after ARDS onset was lower in the lower-threshold group (subdistribution hazard ratio, 0.36 [95%-CI, 0.15-0.86], P = 0.02).

CONCLUSIONS

Transfusion at a hemoglobin concentration of 8 g/dl, as compared with a hemoglobin concentration of 10 g/dl, was not associated with an increase in 28-day mortality in adults with ARDS. However, a transfusion at a hemoglobin concentration of 8 g/dl was associated with a lower chance for successful weaning from the ventilator during the first 28 days after ARDS onset.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03871166.

Prolonged Weaning: S2k Guideline Published by the German Respiratory Society

Mechanical ventilation (MV) is an essential part of modern intensive care medicine. MV is performed in patients with severe respiratory failure caused by respiratory muscle insufficiency and/or lung parenchymal disease; that is, when other treatments such as medication, oxygen administration, secretion management, continuous positive airway pressure (CPAP), or nasal high-flow therapy have failed. MV is required for maintaining gas exchange and allows more time to curatively treat the underlying cause of respiratory failure. In the majority of ventilated patients, liberation or "weaning" from MV is routine, without the occurrence of any major problems. However, approximately 20% of patients require ongoing MV, despite amelioration of the conditions that precipitated the need for it in the first place. Approximately 40-50% of the time spent on MV is required to liberate the patient from the ventilator, a process called "weaning". In addition to acute respiratory failure, numerous factors can influence the duration and success rate of the weaning process; these include age, comorbidities, and conditions and complications acquired during the ICU stay. According to international consensus, "prolonged weaning" is defined as the weaning process in patients who have failed at least 3 weaning attempts, or require more than 7 days of weaning after the first spontaneous breathing trial (SBT). Given that prolonged weaning is a complex process, an interdisciplinary approach is essential for it to be successful. In specialised weaning centres, approximately 50% of patients with initial weaning failure can be liberated from MV after prolonged weaning. However, the heterogeneity of patients undergoing prolonged weaning precludes the direct comparison of individual centres. Patients with persistent weaning failure either die during the weaning process, or are discharged back to their home or to a long-term care facility with ongoing MV. Urged by the growing importance of prolonged weaning, this Sk2 Guideline was first published in 2014 as an initiative of the German Respiratory Society (DGP), in conjunction with other scientific societies involved in prolonged weaning. The emergence of new research, clinical study findings and registry data, as well as the accumulation of experience in daily practice, have made the revision of this guideline necessary. The following topics are dealt with in the present guideline: Definitions, epidemiology, weaning categories, underlying pathophysiology, prevention of prolonged weaning, treatment strategies in prolonged weaning, the weaning unit, discharge from hospital on MV, and recommendations for end-of-life decisions. Special emphasis was placed on the following themes: (1) A new classification of patient sub-groups in prolonged weaning. (2) Important aspects of pulmonary rehabilitation and neurorehabilitation in prolonged weaning. (3) Infrastructure and process organisation in the care of patients in prolonged weaning based on a continuous treatment concept. (4) Changes in therapeutic goals and communication with relatives. Aspects of paediatric weaning are addressed separately within individual chapters. The main aim of the revised guideline was to summarize both current evidence and expert-based knowledge on the topic of "prolonged weaning", and to use this information as a foundation for formulating recommendations related to "prolonged weaning", not only in acute medicine but also in the field of chronic intensive care medicine. The following professionals served as important addressees for this guideline: intensivists, pulmonary medicine specialists, anaesthesiologists, internists, cardiologists, surgeons, neurologists, paediatricians, geriatricians, palliative care clinicians, rehabilitation physicians, intensive/chronic care nurses, physiotherapists, respiratory therapists, speech therapists, medical service of health insurance, and associated ventilator manufacturers.

Randomized controlled multicentre study of albumin replacement therapy in septic shock (ARISS): protocol for a randomized controlled trial

BACKGROUND

Albumin is a key regulator of fluid distribution within the extracellular space and has several properties beyond its oncotic activity. The accumulating evidence suggests that supplementation of albumin may provide survival advantages only when the insult is severe as in patients with septic shock.

METHODS/DESIGN

The randomized controlled multicentre study of albumin replacement therapy in septic shock (ARISS) investigates whether the replacement with albumin and the maintenance of its serum levels of at least 30 g/l for 28 days improve survival in patients with septic shock compared to resuscitation and volume maintenance without albumin. Adult patients (≥ 18 years) with septic shock are randomly assigned within a maximum of 24 h after the onset of septic shock after obtaining informed consents to treatment or control groups. Patients assigned to the treatment group receive a 60-g loading dose of human albumin 20% over 2-3 h. Serum albumin levels are maintained at least at 30 g/l in the ICU for a maximum of 28 days following randomization using 40-80 g human albumin 20% infusion. The control group is treated according to the usual practice with crystalloids as the first choice for the resuscitation and maintenance phase of septic shock. The primary endpoint is 90 days mortality and secondary endpoints include 28-day, 60-day, ICU, and in-hospital mortality, organ dysfunction/failure, total amount of fluid administration and total fluid balance in the ICU, and lengths of ICU and hospital stay. In total, 1412 patients need to be analysed, 706 per group. For the sample size estimation, a 15% reduction in 90-day mortality is assumed, i.e. an absolute reduction of 7.5% points to 42.5% (relative risk 1.18). Assuming a dropout rate of 15%, a total of 1662 patients need to be allocated.

DISCUSSION

The results of the clinical trial may influence the treatment of patients with septic shock. The expected improvement in patient survival may result in a reduction in the resources currently used in the treatment of these patients and in the socioeconomic burden of this disease.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03869385 . Registration on 18 July 2019. Protocol version: Final 3.0.

Monitoring mitochondrial PO2: the next step

PURPOSE OF REVIEW

To fully exploit the concept of hemodynamic coherence in resuscitating critically ill one should preferably take into account information about the state of parenchymal cells. Monitoring of mitochondrial oxygen tension (mitoPO2) has emerged as a clinical means to assess information of oxygen delivery and oxygen utilization at the mitochondrial level. This review will outline the basics of the technique, summarize its development and describe the rationale of measuring oxygen at the mitochondrial level.

RECENT FINDINGS

Mitochondrial oxygen tension can be measured by means of the protoporphyrin IX-Triplet State Lifetime Technique (PpIX-TSLT). After validation and use in preclinical animal models, the technique has recently become commercially available in the form of a clinical measuring system. This system has now been used in a number of healthy volunteer studies and is currently being evaluated in studies in perioperative and intensive care patients in several European university hospitals.

SUMMARY

PpIX-TSLT is a noninvasive and well tolerated method to assess aspects of mitochondrial function at the bedside. It allows doctors to look beyond the macrocirculation and microcirculation and to take the oxygen balance at the cellular level into account in treatment strategies.

Transfusion in critical care: Past, present and future

Anaemia and coagulopathy are common in critically ill patients and are associated with poor outcomes, including increased risk of mortality, myocardial infarction, failure to be liberated from mechanical ventilation and poor physical recovery. Transfusion of blood and blood products remains the corner stone of anaemia and coagulopathy treatment in critical care. However, determining when the benefits of transfusion outweigh the risks of anaemia may be challenging in some critically ill patients. Therefore, the European Society of Intensive Care Medicine prioritised the development of a clinical practice guideline to address anaemia and coagulopathy in non-bleeding critically ill patients. The aims of this article are to: (1) review the evolution of transfusion practice in critical care and the direction for future developments in this important area of transfusion medicine and (2) to provide a brief synopsis of the guideline development process and recommendations in a format designed for busy clinicians and blood bank staff. These clinical practice guidelines provide recommendations to clinicians on how best to manage non-bleeding critically ill patients at the bedside. More research is needed on alternative transfusion targets, use of transfusions in special populations (e.g., acute neurological injury, acute coronary syndromes), use of anaemia prevention strategies and point-of-care interventions to guide transfusion strategies.

Blood Utilization and Clinical Outcomes in Extracorporeal Membrane Oxygenation Patients

BACKGROUND

Patients requiring extracorporeal membrane oxygenation (ECMO) support are critically ill and have substantial transfusion requirements, which convey both risks and benefits. A retrospective analysis was conducted to assess the association between blood component administration and adverse outcomes in adult, pediatric, and neonatal ECMO patients.

METHODS

We evaluated 217 ECMO patients at a single center hospitalized between January 2009 and June 2016. Three cohorts (88 adult, 57 pediatric, and 72 neonatal patients) were included for assessment of patient characteristics, blood utilization, and clinical outcomes. Univariable and multivariable analyses were used to assess the association between transfusions and clinical outcomes (primary outcome: mortality and secondary outcomes: morbid events). The analysis included the main exposure of interest (total number of blood component units transfused) and potential confounding variables (age group cohort, case mix index, sex, ECMO mode and duration, and primary ECMO indication).

RESULTS

After adjustment for confounders, with each additional blood component unit transfused, there was an estimated increase in odds for mortality by 1% (odds ratio [OR] = 1.01; 95% confidence interval [CI], 1.00-1.02; P = .013) and an increase in odds for thrombotic events by 1% (OR = 1.01; 95% CI, 1.00-1.02; P = .007). Mortality was higher in the adult (57 of 88; 64.8%) and pediatric (37 of 57; 64.9%) than in the neonatal cohort (19 of 72; 26.4%) (P < .0001). Median total blood components transfused per day followed a similar pattern for the adult (2.3 units; interquartile range [IQR] = 0.8-7.0), pediatric (2.9 units; IQR = 1.1-10), and neonatal (1.0 units; IQR = 0.7-1.6) cohorts (P < .0001). Over the entire hospitalization, the total median blood components transfused was highest in the neonatal (41 units; IQR = 24-94) and pediatric (41 units; IQR = 17-113) compared to the adult (30 units; IQR = 9-58) cohort (P = .007). There was no significant interaction between total units transfused over the hospital stay and age cohort for mortality (P = .35).

CONCLUSIONS

Given the association between transfusion and adverse outcomes, effective blood management strategies may be beneficial in ECMO patients.

Factors influencing the bias between blood gas analysis versus central laboratory hemoglobin testing. A secondary analysis of a randomized controlled trial

BACKGROUND

Anemia is the most important complication during major surgery and transfusion of red blood cells is the mainstay to compensate for life threating blood loss. Therefore, accurate measurement of hemoglobin (Hb) concentration should be provided in real-time. Blood Gas Analysis (BGA) provides rapid point-of-care assessment using smaller sampling tubes compared to central laboratory (CL) services.

OBJECTIVE

This study aimed to investigate the accuracy of BGA hemoglobin testing as compared to CL services.

METHODS

Data of the ongoing LIBERAL-Trial (Liberal transfusion strategy to prevent mortality and anemia-associated ischemic events in elderly non-cardiac surgical patients, LIBERAL) was used to assess the bias for Hb level measured by BGA devices (ABL800 Flex analyzer®, GEM series® and RapidPoint 500®) and CL as the reference method. For that, we analyzed pairs of Hb level measured by CL and BGA within two hours. Furthermore, the impact of various confounding factors including age, gender, BMI, smoker status, transfusion of RBC, intraoperative hemodilution, and co-medication was elucidated. In order to ensure adequate statistical analysis, only data of participating centers providing more than 200 Hb pairs were used.

RESULTS

In total, three centers including 963 patients with 1,814 pairs of Hb measurements were analyzed. Mean bias was comparable between ABL800 Flex analyzer® and GEM series®: - 0.38 ± 0.15 g/dl whereas RapidPoint 500® showed a smaller bias (-0.09 g/dl) but greater median absolute deviation (± 0.45 g/dl). In order to avoid interference with different standard deviations caused by the different analytic devices, we focused on two centers using the same BGA technique (309 patients and 1,570 Hb pairs). A Bland-Altman analysis and LOWESS curve showed that bias decreased with smaller Hb values in absolute numbers but increased relatively. The smoker status showed the greatest reduction in bias (0.1 g/dl, p<0.001) whereas BMI (0.07 g/dl, p = 0.0178), RBC transfusion (0.06 g/dl, p<0.001), statins (0.04 g/dl, p<0.05) and beta blocker (0.03 g/dl, p = 0.02) showed a slight effect on bias. Intraoperative substitution of volume and other co-medications did not influence the bias significantly.

CONCLUSION

Many interventions like substitution of fluids, coagulating factors or RBC units rely on the accuracy of laboratory measurement devices. Although BGA Hb testing showed a consistently stable difference to CL, our data confirm that BGA devices are associated with different bias. Therefore, we suggest that hospitals assess their individual bias before implementing BGA as valid and stable supplement to CL. However, based on the finding that bias decreased with smaller Hb values, which in turn are used for transfusion decision, we expect no unnecessary or delayed RBC transfusion, and no major impact on the LIBERAL trial performance.

Updates in Sepsis Resuscitation

Sepsis care has evolved significantly since the initial early goal-directed therapy (EGDT) trials. Early fluid resuscitation, source control, and antibiotic therapy remain cornerstones of care but overall understanding is more nuanced, particularly regarding fluid selection, vasopressors, and inotropic support. Timely nutrition therapy and ventilatory support tend to receive less attention but also are important. Recent research has explored immunomodulation, β-blockade, and vitamin supplementation. A renewed emphasis on early, aggressive resuscitation reaffirms the importance of emergency medicine providers knowledgeable and skilled in sepsis management.

RBC Transfusion Triggers: Is There Anything New?

For many years, in daily clinical practice, the traditional 10/30 rule (hemoglobin 10 g/dL - hematocrit 30%) has been the most commonly used trigger for blood transfusions. Over the years, this approach is believed to have contributed to a countless number of unnecessary transfusions and an unknown number of overtransfusion-related deaths. Recent studies have shown that lower hemoglobin levels can safely be accepted, even in critically ill patients. However, even these new transfusion thresholds are far beyond the theoretical limits of individual anemia tolerance. For this reason, almost all publications addressing the limits of acute anemia recommend physiological transfusion triggers to indicate the transfusion of erythrocyte concentrates as an alternative. Although this concept appears intuitive at first glance, no solid scientific evidence supports the safety and benefit of physiological transfusion triggers to indicate the optimal time point for transfusion of allogeneic blood. It is therefore imperative to continue searching for the most sensitive and specific parameters that can guide the clinician when to transfuse in order to avoid anemia-induced organ dysfunction while avoiding overtransfusion-related adverse effects. This narrative review discusses the concept of anemia tolerance and critically compares hemoglobin-based triggers with physiological transfusion for various clinical indications.

Deciphering the role of Wnt signaling in acute myeloid leukemia prognosis: how alterations in DNA methylation come into play in patients' prognosis

Acute myeloid leukemia (AML) is a malignant clonal disorder affecting myeloid differentiation through mechanisms that include epigenetic dysregulation. Abnormal changes in DNA methylation and gene expression profiles of pathways involved in hematopoietic development, such as Wnt/β-catenin, contribute to the transformation, development, and maintenance of leukemic cells. This review summarizes the alterations of Wnt signaling-related genes at the epigenetic and transcriptional level and their implications for AML prognosis. Among the implications of epigenetic alterations in AML, methylation of Wnt antagonists is related to poor prognosis, whereas their upregulation has been associated with a better clinical outcome. Furthermore, Wnt target genes c-Myc and LEF-1 present distinct implications. LEF-1 expression positively influences the patient overall survival. c-Myc upregulation has been associated with treatment resistance in AML, although c-Myc expression is not exclusively dependent of Wnt signaling. Understanding the signaling abnormalities could help us to further understand leukemogenesis, improve the current risk stratification for AML patients, and even serve to propose novel therapeutic targets.