0
selected
-
1.
Modulation of Hb-O2 affinity to improve hypoxemia in COVID-19 patients.
Woyke, S, Rauch, S, Ströhle, M, Gatterer, H
Clinical nutrition (Edinburgh, Scotland). 2021;(1):38-39
-
-
Free full text
-
Abstract
This opinion paper aims at discussing the potential impact of modulating the Hb-O2 affinity by the nutritional supplement 5-HMF on patients affected by COVID-19. The paper describes the critical role of the oxygen affinity in hypoxemic COVID-19 patients and the potential positive effect of 5-HMF, a compound shown to increase the Hb-O2 affinity.
-
2.
Methods and analyzers for hemoglobin measurement in clinical laboratories and field settings.
Whitehead, RD, Mei, Z, Mapango, C, Jefferds, MED
Annals of the New York Academy of Sciences. 2019;(1):147-171
-
-
Free full text
-
Abstract
This paper describes and compares methods and analyzers used to measure hemoglobin (Hb) in clinical laboratories and field settings. We conducted a literature review for methods used to measure Hb in clinical laboratories and field settings. We described methods to measure Hb and factors influencing results. Automated hematology analyzer (AHA) was reference for all Hb comparisons using evaluation criteria of ±7% set by College of American Pathologists (CAP) and Clinical Laboratory Improvement Amendments (CLIA). Capillary fingerprick blood usually produces higher Hb concentrations compared with venous blood. Individual drops produced lower concentrations than pooled capillary blood. Compared with the AHA: (1) overall cyanmethemoglobin (1.0-8.0 g/L), WHO Colour Scale (0.5-10.0 g/L), paper-based devices (5.0-7.0 g/L), HemoCue® Hb-201 (1.0-16.0 g/L) and Hb-301 (0.5-6.0 g/L), and Masimo Pronto® (0.3-14.0 g/L) overestimated concentrations; (2) Masimo Radical®-7 both under- and overestimated concentrations (0.3-104.0 g/L); and (3) other methods underestimated concentrations (2.0-16.0 g/L). Most mean concentration comparisons varied less than ±7% of the reference. Hb measurements are influenced by several analytical factors. With few exceptions, mean concentration bias was within ±7%, suggesting acceptable performance. Appropriate, high-quality methods in all settings are necessary to ensure the accuracy of Hb measurements.This paper describes and compares methods and analyzers used to measure hemoglobin (Hb) in clinical laboratories and field settings. With few exceptions, mean concentration bias was within ±7%, suggesting acceptable performance. Appropriate, high-quality methods in all settings are necessary to ensure the accuracy of Hb measurements.
-
3.
Iron Deficiency in Heart Failure: An Overview.
von Haehling, S, Ebner, N, Evertz, R, Ponikowski, P, Anker, SD
JACC. Heart failure. 2019;(1):36-46
Abstract
Iron deficiency is an extremely common comorbidity in patients with heart failure, affecting up to 50% of all ambulatory patients. It is associated with reduced exercise capacity and physical well-being and reduced quality of life. Cutoff values have been identified for diagnosing iron deficiency in heart failure with reduced ejection fraction as serum ferritin, <100 μg/l, or ferritin, 100 to 300 μg/l, with transferrin saturation of <20%. Oral iron products have been shown to have little efficacy in heart failure, where the preference is intravenous iron products. Most clinical studies have been performed using ferric carboxymaltose with good efficacy in terms of improvements in 6-min walk test distance, peak oxygen consumption, quality of life, and improvements in New York Heart Association functional class. Data from meta-analyses also suggest beneficial effects for hospitalization rates for heart failure and reduction in cardiovascular mortality rates. A prospective trial to investigate effects on morbidity and mortality is currently ongoing. This paper highlights current knowledge of the pathophysiology of iron deficiency in heart failure, its prevalence and clinical impact, and its possible treatment options.
-
4.
Use and interpretation of hemoglobin concentrations for assessing anemia status in individuals and populations: results from a WHO technical meeting.
Garcia-Casal, MN, Pasricha, SR, Sharma, AJ, Peña-Rosas, JP
Annals of the New York Academy of Sciences. 2019;(1):5-14
-
-
Free full text
-
Abstract
Anemia is an important public health problem that negatively affects health of individuals and economic potential of populations. An accurate case definition is critical for understanding burden and epidemiology of anemia, for planning public health interventions, and for clinical investigation and treatment of patients. The current threshold hemoglobin concentrations for diagnosis of anemia were proposed in 1968 and based on studies predominantly of Caucasian adult populations in Europe and North America. The World Health Organization is undertaking a project to review global guidelines for anemia. We describe the process of obtaining input from technical experts, researchers, blood bank experts, policy makers, and program implementers to identify key information or knowledge gaps for anemia diagnosis. From this scoping exercise, six priority areas were identified on diverse topics related to the use and interpretation of hemoglobin concentrations to diagnose anemia in individuals and populations. A call for authors was conducted to produce background, review, and research papers across priority topics. This paper summarizes the first technical meeting, which included commissioned papers as well as case studies, describes key data gaps identified, and describes the next steps in the guideline development process to assess available evidence and define knowledge gaps to improve anemia characterization.
-
5.
Anemia and acute coronary syndrome: current perspectives.
Stucchi, M, Cantoni, S, Piccinelli, E, Savonitto, S, Morici, N
Vascular health and risk management. 2018;:109-118
Abstract
Reference hemoglobin (Hb) values for the definition of anemia are still largely based on the 1968 WHO Scientific Group report, which established a cutoff value of <13 g/dL for adult men and <12 g/dL for adult nonpregnant women. Subsequent studies identified different normal values according to race and age. Estimated prevalence of anemia on admission in the setting of an acute coronary syndrome (ACS) is between 10% and 43% of the patients depending upon the specific population under investigation. Furthermore, up to 57% of ACS patients may develop hospital-acquired anemia (HAA). Both anemia on admission and HAA are associated with worse short- and long-term mortality, even if different mechanisms contribute to their prognostic impact. Baseline anemia can usually be traced back to preexisting disease that should be specifically investigated and corrected whenever possible. HAA is associated with clinical characteristics, medical therapy and interventional procedures, all eliciting cardiovascular adaptive response that can potentially worsen myocardial ischemia. The intrinsic fragility of anemic patients may limit aggressive medical and interventional therapy due to an increased risk of bleeding, and could independently contribute to worse outcome. However, primary angioplasty for ST elevation ACS should not be delayed because of preexisting (and often not diagnosed) anemia; delaying revascularization to allow fast-track anemia diagnosis is usually feasible and justified in non-ST-elevation ACS. Besides identification and treatment of the underlying causes of anemia, the only readily available means to reverse anemia is red blood cell transfusion. The adequate transfusion threshold is still being debated, although solid evidence suggests reserving red blood cell transfusions for patients with Hb level <8 g/dL and considering it in selected cases with Hb levels of between 8 and 10 g/dL. No evidence supports the use of iron supplements and erythropoiesis-stimulating agents in the setting of ACS.
-
6.
U-shaped curve for risk associated with maternal hemoglobin, iron status, or iron supplementation.
Dewey, KG, Oaks, BM
The American journal of clinical nutrition. 2017;(Suppl 6):1694S-1702S
-
-
Free full text
-
Abstract
Both iron deficiency (ID) and excess can lead to impaired health status. There is substantial evidence of a U-shaped curve between the risk of adverse birth outcomes and maternal hemoglobin concentrations during pregnancy; however, it is unclear whether those relations are attributable to conditions of low and high iron status or to other mechanisms. We summarized current evidence from human studies regarding the association between birth outcomes and maternal hemoglobin concentrations or iron status. We also reviewed effects of iron supplementation on birth outcomes among women at low risk of ID and the potential mechanisms for adverse effects of high iron status during pregnancy. Overall, we confirmed a U-shaped curve for the risk of adverse birth outcomes with maternal hemoglobin concentrations, but the relations differ by trimester. For low hemoglobin concentrations, the link with adverse outcomes is more evident when hemoglobin concentrations are measured in early pregnancy. These relations generally became weaker or nonexistent when hemoglobin concentrations are measured in the second or third trimesters. Associations between high hemoglobin concentration and adverse birth outcomes are evident in all 3 trimesters but evidence is mixed. There is less evidence for the associations between maternal iron status and adverse birth outcomes. Most studies used serum ferritin (SF) concentrations as the indicator of iron status, which makes the interpretation of results challenging because SF concentrations increase in response to inflammation or infection. The effect of iron supplementation during pregnancy may depend on initial iron status. There are several mechanisms through which high iron status during pregnancy may have adverse effects on birth outcomes, including oxidative stress, increased blood viscosity, and impaired systemic response to inflammation and infection. Research is needed to understand the biological processes that underlie the U-shaped curves seen in observational studies. Reevaluation of cutoffs for hemoglobin concentrations and indicators of iron status during pregnancy is also needed.
-
7.
The Role of Hemoproteins: Hemoglobin, Myoglobin and Neuroglobin in Endogenous Thiosulfate Production Processes.
Bilska-Wilkosz, A, Iciek, M, Górny, M, Kowalczyk-Pachel, D
International journal of molecular sciences. 2017;(6)
Abstract
Thiosulfate formation and biodegradation processes link aerobic and anaerobic metabolism of cysteine. In these reactions, sulfite formed from thiosulfate is oxidized to sulfate while hydrogen sulfide is transformed into thiosulfate. These processes occurring mostly in mitochondria are described as a canonical hydrogen sulfide oxidation pathway. In this review, we discuss the current state of knowledge on the interactions between hydrogen sulfide and hemoglobin, myoglobin and neuroglobin and postulate that thiosulfate is a metabolically important product of this processes. Hydrogen sulfide oxidation by ferric hemoglobin, myoglobin and neuroglobin has been defined as a non-canonical hydrogen sulfide oxidation pathway. Until recently, it appeared that the goal of thiosulfate production was to delay irreversible oxidation of hydrogen sulfide to sulfate excreted in urine; while thiosulfate itself was only an intermediate, transient metabolite on the hydrogen sulfide oxidation pathway. In the light of data presented in this paper, it seems that thiosulfate is a molecule that plays a prominent role in the human body. Thus, we hope that all these findings will encourage further studies on the role of hemoproteins in the formation of this undoubtedly fascinating molecule and on the mechanisms responsible for its biological activity in the human body.
-
8.
Systematic review of randomized trials of the effect of iron supplementation on iron stores and oxygen carrying capacity in pregnancy.
Daru, J, Cooper, NA, Khan, KS
Acta obstetricia et gynecologica Scandinavica. 2016;(3):270-9
-
-
Free full text
-
Abstract
INTRODUCTION Anemia in pregnancy affects 25% of all pregnancies in Europe with iron deficiency affecting even more. Despite supplementation, iron deficiency persists. This review will assess the effect on serum ferritin (iron stores) and hemoglobin (oxygen-carrying capacity) following iron supplementation in pregnant women with anemic and non-anemic iron deficiency. MATERIAL AND METHODS A systemic search of electronic databases and trial registers was conducted from inception to January 2014. Randomized controlled trials of iron supplementation that measured serum ferritin and hemoglobin levels before and after supplementation were selected. Two independent reviewers selected studies, extracted data and assessed quality. Descriptive analyses were carried out. RESULTS The review included 23 randomized controlled trials (3525 women). In iron deficiency anemia, more studies described statistically significant increases in serum ferritin levels than in hemoglobin levels following intravenous iron supplementation. In non-anemic iron deficiency there were more statistically significant increases in serum ferritin levels than in hemoglobin levels following oral supplementation. There were no studies reporting maternal quality of life outcomes. CONCLUSIONS Serum ferritin appears to change more than hemoglobin following iron supplementation. The clinical effects of this need further investigation.
-
9.
Efficacy and Safety of Ferric Carboxymaltose and Other Formulations in Iron-Deficient Patients: A Systematic Review and Network Meta-analysis of Randomised Controlled Trials.
Rognoni, C, Venturini, S, Meregaglia, M, Marmifero, M, Tarricone, R
Clinical drug investigation. 2016;(3):177-94
-
-
Free full text
-
Abstract
BACKGROUND Iron deficiency is very common in a number of medical conditions. Ferric carboxymaltose is a new stable iron preparation that can be administered in single infusions over short periods of time. The aim of this study was to conduct a systematic review of randomised controlled trials (RCTs) regarding the efficacy and safety of the novel complex compared with other iron formulations. In addition, the feasibility of a network meta-analysis for indirect comparisons was investigated. METHODS A systematic literature review was performed for published RCTs on the use of ferric carboxymaltose in iron deficiency between July and October 2014. Indirect comparisons were also addressed using terms referring to competing iron formulations. We further supported the qualitative results of the systematic review by a network meta-analysis that allows pooling the evidence around different intervention outcomes in the absence of trials involving a direct comparison. RESULTS The initial search yielded 1027 citations, which was decreased to 21 studies eligible for inclusion in the review. Studies were heterogeneous in the number of patients randomised, iron deficiency-related conditions addressed, trial inclusion criteria, time horizon, treatment dosage and outcomes assessed. Six studies with the same time horizon (i.e. 6 weeks) were included in the network meta-analysis. Considering the differences between final and initial outcome values for each iron formulation, the mean difference of these differences (delta) was estimated for each couple of treatments involving ferric carboxymaltose. Significant improvements in serum ferritin (µg/l) were obtained with ferric carboxymaltose compared to oral iron (delta 172.8; 95 % CI 66.7-234.4) and in haemoglobin (g/dl) with respect to ferric gluconate (delta 0.6; 95 % CI 0.2-0.9), oral iron (delta 0.8; 95 % CI 0.6-0.9) and placebo (delta 2.1; 95 % CI 1.2-3.0). CONCLUSIONS All currently available intravenous iron preparations appear to be safe and effective, but ferric carboxymaltose seems to provide a better and quicker correction of haemoglobin and serum ferritin levels in iron-deficient patients.
-
10.
How the Target Hemoglobin of Renal Anemia Should Be.
Mimura, I, Tanaka, T, Nangaku, M
Nephron. 2015;(3):202-9
Abstract
Renal anemia is caused by the deficiency of endogenous erythropoietin (Epo) due to renal dysfunction. We think that it is possible to slow the progression of chronic kidney disease (CKD) in case we initiate Epo early in pre-dialysis patients, especially in the non-diabetic population. Erythropoiesis stimulating agent (ESA) treatments targeting mild anemia (10-12 g/dl) can decrease the risk of occurrence of cardiovascular disease (CVD) in patients with hypertension, diabetes mellitus and congestive heart failure. As the large randomized controlled trials such as Cardiovascular Risk Reduction by Early Anemia Treatment with Epoetin Beta, Correction of Hemoglobin and Outcomes in Renal Insufficiency and Trial to Reduce Cardiovascular Events with Aranesp Thearpy in the Western countries suggested, we do not recommend high doses of ESA to achieve the target hemoglobin (Hb) level. The target Hb of >13 g/dl might lead to increase in the risk of CVD although maintaining a high Hb of >12 g/dl without ESA is not harmful for CKD patients. It is desirable to determine the target Hb in dialysis patients depending on their ages. Renal anemia should be monitored constantly to start ESA and iron replacement therapy at an appropriate time, while avoiding their excess in order to minimize the occurrence of CVD and other complications. Taken all the international guidelines and our clinical experiences together, we should consider administration of ESA when the Hb level becomes <11 g/dl in pre-dialysis patients and <10 g/dl in dialysis patients.