Fatal Hemoptysis With Pleural Effusions Secondary to Superior Vena Cava Obstruction as a Complication of Central Venous Catheterization.

This report outlines a rare case of superior vena cava (SVC) syndrome presenting with hemoptysis in a 33-year-old female Jehovah's Witness patient with a complex medical history, including systemic lupus erythematosus (SLE) and chronic hemodialysis dependency due to end-stage renal disease and a failed renal transplant. The SVC syndrome was attributed to occlusion from a right subclavian dialysis catheter. The management of this case was particularly challenging due to the patient's severe anemia and the development of a tension hemothorax following thoracentesis, compounded by her refusal of blood transfusions in adherence to her religious beliefs. A multidisciplinary approach, incorporating bloodless medical techniques such as erythropoietin and iron infusions alongside surgical interventions without blood transfusion, was successfully employed. This case sheds light on the evolving etiology of SVC syndrome and highlights the uncommon but potentially fatal occurrence of hemoptysis as a complication. It also emphasizes the importance of respecting patient values in complex medical decisions.

Severe B12 Deficiency Causing a Maturation Defect Mimicking Myelodysplastic Syndrome With Excess Blasts.

Vitamin B12 deficiency is a common condition that is often asymptomatic, though in severe cases may cause megaloblastic anemia and even neurologic symptoms. Occasionally, the clinical presentation can include pancytopenia and thus mimic a more concerning myelodysplastic syndrome (MDS) until corrected by B12 supplementation. In this unusual case, we present a patient with B12 deficiency who presents with severe macrocytic anemia, neutropenia, lymphocytosis, and a bone marrow morphology consistent with MDS.

A Rare Case of Acute Pancreatitis as an Initial Presentation of Acute Myeloid Leukemia.

Acute pancreatitis is a rare manifestation of acute myeloid leukemia which can be a presentation at the initial diagnosis or during or after the onset of the disease. Acute myeloid leukemia occurs due to the abnormal proliferation of undifferentiated hematopoietic stem cells in the bone marrow which alter the normal hematopoiesis. We report the case of a 32-year-old male admitted with a one-month history of fever and backache, followed by 15 days of blackish stool discoloration and two days of abdominal pain and reduced urine output. On clinical examination, he was hypoxic with respiratory distress with epigastric tenderness. Blood investigations and imaging were consistent with acute pancreatitis. A complete blood count with peripheral smear showed severe normocytic normochromic anemia and an increased myeloid series containing 50% myeloblasts and 30% monoblasts. Additionally, some cells displayed cytoplasmic vacuolations, with a reticulocyte count of 2%. These findings were suggestive of acute myeloid leukemia M5. Due to the poor Glasgow Coma Scale (GCS), he was intubated and placed on mechanical ventilation. Unfortunately, he did not improve despite treatment and succumbed to the illness.

Multiple Ulcers in the Ileum and Lymphadenopathy Following the Usage of Methotrexate in a Patient With Rheumatoid Arthritis: A Case Report.

This case report aims to highlight a rare occurrence of severe anemia and lymphadenopathy secondary to methotrexate (MTX)-induced ileal mucosa damage in a patient with elderly onset rheumatoid arthritis (EORA). We present the case of a 72-year-old female with a history of EORA, treated with MTX, who exhibited hematochezia without accompanying pain, diarrhea, or known infectious contacts. Diagnostic investigations included imaging and endoscopic procedures. The patient's presentation of severe anemia was atypical, given the absence of significant pain or discomfort associated with EORA. The lack of active bleeding observed during endoscopy, coupled with multiple ileal ulcers, suggested a chronic progression of mucosal damage. Laboratory findings, including normal lactate dehydrogenase, soluble interleukin-2 receptor levels, and the absence of malignancy in mucosal biopsies, ruled out MTX-induced lymphoma. The patient's condition improved with the cessation of MTX and the introduction of symptomatic treatment and anemia management. This case underscores the need for vigilant monitoring and comprehensive evaluation in patients with RA, especially the elderly, treated with MTX. It also highlights the importance of considering drug-induced complications in the differential diagnosis of anemia. The case demonstrates the necessity of a personalized approach to treatment, emphasizing regular follow-ups and adjustments based on the patient's response to therapy. This report contributes to the growing body of evidence on the complexities of managing RA in the elderly, particularly regarding the side effects of common medications like MTX.

Severe Anemia from Multiple Gastric Hyperplastic Polyps in a Hemodialysis Patient after Long-term Use of a Proton-pump Inhibitor.

A 90-year-old man on maintenance hemodialysis was admitted due to severe symptomatic anemia. Biopsies under esophagogastroduodenoscopy demonstrated that the cause of anemia was intermittent blood oozing from multiple gastric hyperplastic polyps. Even after successful eradication of Helicobacter pylori, he showed hypergastrinemia (480 pg/mL) owing to esomeprazole (proton-pump inhibitor) therapy for the past 4.5 years to treat reflux esophagitis. Seven months after we switched esomeprazole to famotidine (H2-receptor antagonist), those gastric polyps and anemia were remarkably ameliorated with lowered gastrin levels. This case indicates that long-term use of a proton-pump inhibitor triggers chronic hypergastrinemia, leading to gastric hyperplastic polyps and subsequent severe anemia.

Anesthesia Approach to Managing Severe Hemorrhagic Shock and Anemia With Non-transfusion Alternatives in a Practicing Jehovah's Witness: A Case Report.

Traumatic hemorrhagic shock is a common yet life-threatening occurrence across the United States and is typically managed with blood transfusions as the standard of care. However, providers caring for a Jehovah's Witness patient who refuses transfusions due to religious reasons face unique ethical challenges in upholding evidence-based shock resuscitation protocols while respecting the patient's autonomy and faith-based stance that strictly prohibits blood products. We present a complex clinical case of a 46-year-old Jehovah's Witness who developed severe hemorrhagic shock, partial amputation, and critical anemia after a traumatic 40-mile-per-hour motorcycle collision resulting in comminuted fractures and arterial disruption. Despite receiving emergent blood transfusions initially, further transfusions were declined once his identity as a practicing Jehovah's Witness was disclosed. His hemoglobin plunged to dangerously low levels of 4.6 g/dL before stabilizing to 5.3 g/dL with pharmaceutical alternatives including intravenous iron, high-dose erythropoietin, and phlebotomy minimization. Respecting patient convictions while delivering effective evidence-based shock management created significant ethical conflicts given the proven efficacy of blood transfusions. However, this complex case demonstrates that through meticulous medical and surgical care coordinated by a multi-disciplinary team applying customized non-transfusion techniques, traumatic hemorrhagic shock and life-threatening anemia can still achieve favorable outcomes without relying on transfusions when respecting faith-based refusal of blood products.

Effect of IV ferric carboxy maltose for moderate/severe anemia: a systematic review and meta-analysis.

Introduction: Anemia remains a prevalent global health issue with varying severity. Intravenous iron supplementation, particularly with ferric carboxymaltose (FCM), has appeared as a possible therapeutic intervention for individuals with moderate to severe anemia. The study aimed to assess the efficacy and safety of ferric carboxymaltose (FCM) in reducing anemia. Methods: We searched electronic databases, registries, websites, e-libraries, reference lists of reviews, citations, etc. We included randomized control trials (RCTs), non-RCTs, and single-arm studies, while observational studies, case series, and case studies were excluded. Two reviewers independently screened the studies and extracted the data. We included studies of moderate-to-severely anemic Indians and excluded Indians with other comorbidities. We assessed the risk of bias and the overall quality of evidence (QoE) using GRADE GDT. Result: We identified 255 studies and included 14 studies (11 RCT, one non-RCT, and two single-arm studies) with 1,972 participants for qualitative analysis and 10 studies in the meta-analysis. All the included studies detailed the use of FCM for anemia. The primary outcomes assessed in the included studies were anemia, hemoglobin, and adverse events. The outcomes assessed ranged from 2 weeks to 12 weeks. The risk of bias varied across different studies with different outcomes. FCM is consistent with a fewer number of adverse events as compared to other interventions and provides "moderate" to "very low" QoE. Conclusion: A slow single infusion of 1 gram of FCM is well-tolerated, safe, and effective in treating iron deficiency anemia (IDA) and surpasses other interventions (Iron Sucrose Complex (ISC), Iron sucrose, and ferrous ascorbate) in elevating hemoglobin levels and replenishing iron stores. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=459363, CRD42023459363.

Management of Severe Anemia in a Jehovah's Witness Patient With Lung Abscess Secondary to Malpositioned Laparoscopic Adjustable Gastric Band: A Case Report.

Jehovah's Witnesses is a Christian denomination widely recognized for their steadfast refusal of blood transfusions, even when facing severe anemia. We describe a unique case of a 42-year-old Jehovah's Witness woman with severe iron deficiency anemia. She necessitated surgical correction of a malpositioned gastric band within the context of a complex necrotizing aspiration pneumonia secondary to esophageal obstruction. Medical management of this severe anemia has been a challenge as traditional approaches, like a blood transfusion, are not possible. Instead, a multifaceted approach has been described with intravenous iron infusions, recombinant human erythropoietin, vitamin B12, folate, and vitamin C administration. We emphasize the lack of consensus on guideline protocols regarding management of severe anemia for Jehovah's Witness patients and the subsequent need for more investigation into that matter. It also underscores the significance of respecting patient autonomy through close collaboration between patients and their health care providers to ensure effective patient-centered care.

Lesión pulmonar aguda producida por transfusión (TRALI): Reporte de caso / Transfusion-induced acute lung injury (TRALI): Case report

Introducción: La lesión pulmonar aguda (TRALI) y la sobrecarga circulatoria (TACO) son las principales causas de morbilidad y mortalidad relacionadas con la transfusión. La TRALI se presenta durante o después de las transfusiones de plasma y sus derivados, o por inmunoglobulinas en alta concentración intravenosa; se asocia a procesos sépticos, cirugías y transfusiones masivas. La TACO es la exacerbación de manifestaciones respiratorias en las primeras 6 horas postransfusión. Reporte caso: Paciente de sexo masculino de 38 días de vida, ingresó al servicio de urgencias con un cuadro clínico de 8 días de evolución, caracterizado por dificultad respiratoria dado por retracciones subcostales y aleteo nasal sin otro síntoma asociado, con antecedentes de importancia de prematuridad y bajo peso al nacer. El reporte de hemograma arrojó cifras compatibles con anemia severa, por lo que requirió transfusión de glóbulos rojos empaquetados desleucocitados. El paciente presentó un cuadro respiratorio alterado en un periodo menor a 6 horas, por lo que se descartaron causas infecciosas y finalmente se consideró cuadro compatible con TRALI. Conclusiones: Se debe considerar una lesión pulmonar aguda relacionada con una transfusión de sangre si se produce una insuficiencia respiratoria aguda durante o inmediatamente después de la infusión de hemoderivados que contienen plasma.

Introduction: Acute lung injury (TRALI) and circulatory overload (TACO) are the main causes of transfusion-related morbidity and mortality. TRALI occurs during or after transfusions of plasma or its derivatives, or by immunoglobulins in high intravenous concentration; it is associated with septic processes, surgeries, and massive transfusions. TACO is the exacerbation of respiratory manifestations in the first 6 hours post transfusion. Case report: A 38-day-old male was admitted to the emergency department with clinical symptoms experienced over the course of 8 days and characterized by respiratory distress due to subcostal retractions and nasal flaring with no other associated symptoms. Important antecedents included prematurity and low birth weight. The hemogram report showed figures compatible with anemia, which benefited from transfusion of packed red blood cells without leukocytes. In a period of less than 6 hours, the patient presented altered respiratory symptoms, practitioners ruled out infectious causes and finally considered clinical signs compatible with TRALI. Conclusion: Acute lung injury related to blood transfusion should be considered if acute respiratory failure occurs during or immediately after infusion of plasma-containing blood products.

The Importance of Early Suspicion for Cold Autoimmune Hemolytic Anemia.

Cold autoimmune hemolytic anemia (cAIHA) is a form of autoimmune hemolytic anemia (AIHA) that most often involves agglutinin antibodies that specifically react to cold temperatures. This process most commonly involves an immunoglobulin M (IgM)-mediated agglutination of erythrocytes and can result in complement-mediated hemolysis, which can range greatly in severity from case to case. Here, we present a case of cAIHA in a 64-year-old male who presented with rapidly progressive and severe hemolytic anemia, which resulted in irreversible decompensation. This case highlights the importance of maintaining a high index of suspicion for cAIHA in patients older adult patients with a previous history of autoimmune hematologic diseases presenting in a rapidly progressive hemolytic state, which can allow for prompt diagnosis, treatment, and mitigation of adverse outcomes.

Red Blood Cell Transfusion after Postpartum Hemorrhage: Clinical Variables Associated with Lack of Postpartum Hemorrhage Etiology Identification.

Postpartum hemorrhage (PPH) remains a significant obstetric emergency worldwide and a leading cause of maternal death. However, it is commonly underreported, which can represent a major concern for maternal morbidity and mortality. This retrospective case series study analyzed patients with red blood cell transfusion (RBCt) in the postpartum period over a four-year interval at a specific center. A total of 18,674 patients delivered between January 2018 and December 2021. Patients with postpartum RBCt were classified into two groups: those with identified PPH (i-PPH) and those without (non-i-PPH). Clinical variables, delivery details, blood loss data, and treatment information were collected. Statistical analysis involved a comparison of variables between the i-PPH and non-i-PPH groups. Univariate and multivariate analyses were performed, aiming to identify significant associations between the clinical variables and a lack of PPH identification. The incidence of RBCt was 1.26% (236 cases). Patients receiving RBCt had higher rates of cesarean delivery, twin pregnancy, labor induction, and previous cesarean section. Among patients with postpartum RBCt, 34.3% lacked an identified PPH. The rarity of postpartum RBCt contrasts with the increasing rates of PPH, highlighting the importance of diagnosing PPH and postpartum anemia. A strategy of systematic quantification of blood loss during delivery could help detect PPH and anemia before adverse consequences occur.

Cord Blood FGF-21 and GDF-15 Levels Are Affected by Maternal Exposure to Moderate to Severe Anemia and Malaria.

Context: Anemia and malaria are global health problems affecting >50% of pregnant women in sub-Saharan Africa and are associated with intrauterine growth restriction. The hormones fibroblast growth factor 21 (FGF-21) and growth differentiation factor 15 (GDF-15) are involved in metabolic regulation and are expressed in the placenta. No studies exist on FGF-21 and GDF-15 responses to exposures of malaria and anemia in pregnancy. Objective and Methods: Using a prospective, longitudinal pregnancy and birth cohort of women with an average age of 26 years from a rural region in northeastern Tanzania, we examined if FGF-21 and GDF-15 levels in maternal blood at week 33 ± 2 (n = 301) and in cord blood at birth (n = 353), were associated with anemia and malaria exposure at different time points in pregnancy and with neonatal anthropometry. Results: Among mothers at gestation week 33 ± 2, lower FGF-21 levels were observed after exposure to malaria in the first trimester, but not anemia, whereas GDF-15 levels at week 33 ± 2 were not associated with malaria nor anemia. In cord blood, moderate to severe anemia at any time point in pregnancy was associated with higher levels of FGF-21, whereas malaria exposure in the third trimester was associated with lower FGF-21 levels in cord blood. Negative associations were observed between cord blood FGF-21 and GDF-15 levels and neonatal skinfold thicknesses and birthweight. Conclusion: Our results suggest that moderate to severe anemia throughout pregnancy associates with higher FGF-21 levels, and malaria in last trimester associates with lower FGF-21 levels, in the neonates, thereby potentially affecting the future cardiometabolic health of the child.

Tackling Anemia in Pregnant Women in India: Reviewing the Obstacles and Charting a Path Forward.

This study examined the obstacles and factors influencing the prevention and treatment of anemia among pregnant women in India. Maintaining antenatal care is essential, leading to favorable birth outcomes and healthier offspring. However, inadequate consumption of essential nutrients is widespread among pregnant women, particularly in lower and middle-income economies such as India, contributing to high maternal and infant mortality rates. The factors influencing anemia prevention and treatment are categorized into individual, socioeconomic, interpersonal, and organizational levels. This study discussed the prevalence of anemia among pregnant women in different states of India. It highlights the interventions and initiatives the government and World Health Organization (WHO) have implemented to address the issue while also emphasizing the need for comprehensive approaches that effectively address the multiple levels of influence needed to prevent and treat anemia. It calls for increased awareness, improved education, and better healthcare services to ensure proper nutrition and iron supplementation. Strengthening healthcare systems and involving family members and healthcare providers in supporting pregnant women are crucial for successful anemia prevention and treatment programs.

Impact of COVID-19 Pandemic on Maternofetal Outcome in Pregnant Women with Severe Anemia.

Background: Anemia is the most common nutritional disease in pregnancy with significant adverse maternofetal outcome. The objective of the present study is to study the impact of COVID-19 pandemic on the pregnancy outcomes of women with severe anemia. Methodology: A retrospective observational study was conducted in the Department of Obstetrics and Gynaecology at LHMC and SSK Hospital, Delhi. The study included all antenatal women admitted at a gestational age of >26 weeks (third trimester) with severe anemia and hemoglobin level of 7 g/dL. In our study, a total of 4031 women were included as cases during study period (July to December 2022) and 6659 women as controls from pre-COVID-19 period (July to December 2019). Results: In present study, a total of 4031 women delivered during study period as compared to 6659 in control period. In the present study, the prevalence of anemia was observed to be 74.7% in the study group and 51.6% in the control group (P < 0.001). Mean hemoglobin level was significantly lower in study group as compared to the control groups P<0.05. Microcytic hypochromic anemia was the most common morphological type of anemia in both groups. Serum ferritin, serum iron, serum B12, and folic acid levels among cases were significantly (P < 0.05) lower as compared to controls. Odds of fetal growth restriction were 1.4 times higher among study group as compared to control groups. The odds of newborn complications such as low birth weight were 2.49 (95% CI: 1.04-5.91) and need for nursery or NICU admission were 4.84 times (95% CI: 0.48-48.24) higher in cases as compared to controls. Low birth rate was higher in cases and was found to be statistically significant. Conclusion: COVID-19 pandemic had indirect impact on adverse maternal and fetal outcome in women with severe anemia.

Hemolytic Anemia in the Setting of Atypical Pneumonia: A Case of Cold Agglutinin Disease.

Cold agglutinin hemolytic anemia (cAHA) is a rare autoimmune disorder characterized by the production of cold agglutinins. We present a case of secondary cAHA in a 23-year-old female with severe anemia and unexplained hemolysis. The patient exhibited findings indicative of hemolysis and a positive direct antiglobulin test (DAT) with complement alone. Additional investigations revealed incidental lung infiltrates, negative serology for infections and autoimmune diseases, and a low cold agglutinin titer. The patient showed a favorable response to doxycycline and supportive therapy, including multiple packed red blood cell transfusions. At the two-week follow-up, the patient had a stable hemoglobin level with no evidence of ongoing hemolysis. This case highlights the importance of considering secondary cAHA in patients with cold symptoms or unexplained hemolysis. Primary cAHA patients may require more aggressive treatment, including rituximab and sutilumab.

Hereditary hemorrhagic telangiectasia in a 42-year-old Ethiopian man presenting with severe anemia and high-output heart failure: A case report with literature review.

Key Clinical Messages: Hereditary hemorrhagic telangiectasia (HHT), a rare hereditary disorder, can cause recurrent massive epistaxis and gastrointestinal bleeding leading to severe anemia. Early diagnosis of HHT is essential to provide timely interventional therapies. Abstract: HHT is a rare autosomal dominant hereditary disease that results in abnormal vasculogenesis in the skin, mucous membranes, and visceral organs such as the liver, lungs, and brain. Clinical diagnosis of HHT is made using the Curacao criteria, which include recurrent spontaneous nosebleeds, mucocutaneous telangiectasias, visceral organ involvement, and first-degree family history of HHT. Here, we report a patient with HHT from Ethiopia, who presented with recurrent epistaxis and gastrointestinal bleeding, and severe anemia requiring frequent blood transfusions as well as cauterization. The presented case is a 42-year-old Black Ethiopian man with frequent hospitalization for severe anemia and high-output heart failure requiring frequent blood transfusions. His mother had bilateral epistaxis since her early adulthood. Physical examination was significant for tachycardia, pale conjunctivae, and tiny erythematous lesions over his tongue, ejection systolic murmur and peripheral edema. Laboratory investigations revealed severe anemia with iron deficiency picture. Upper gastrointestinal endoscopy showed multiple telangiectasia spots and abdominal Doppler ultrasound showed hepatic arterio-venous malformations. He received supportive management and electrocauterization of nasal, gastric, and duodenal telangiectasias. To the best of our knowledge, this is the first case of HHT to be reported from Ethiopia. High degree of suspicion and early diagnosis of HHT is essential to start preventive screening and surveillance and provide timely interventional therapies. HHT can cause recurrent massive epistaxis and gastrointestinal bleeding leading to severe anemia and high-output heart failure. In resource limited settings, selective cauterization of telangiectasia will help to control bleeding, although it does not avoid recurrent bleeding.

Chronic uterine inversion presenting with severe anemia 7 years after a home delivery and the subsequent successful pregnancy: a case report.

BACKGROUND: Uterine inversion is a clinical condition characterized by the folding of the uterine fundus into the uterine cavity or beyond the cervix. Chronic uterine inversions that manifest seven years after delivery are extremely rare, despite the fact that both acute and chronic uterine inversions are infrequent. Unlike uterine inversion during parturition, which can be promptly managed, chronic uterine inversion poses a diagnostic and management challenge. We, herein, report a patient who was managed and followed at our institution for chronic uterine inversion. CASE PRESENTATION: A 28-year-old African female who was referred to our institution with complaints of secondary infertility for seven years, abnormal vaginal bleeding, and lower abdominal pain for 12 months with a mass-like sensation in the vagina. At presentation, she had pale conjunctiva and a protruded, rubbery mass in the cervix with indistinguishable cervical OS on vaginal examination. The patient was resuscitated with intravenous fluids and three units of blood, after which Haultain's procedure was performed. After 16 months on a contraceptive, she was able to conceive and deliver a healthy neonate. CONCLUSION: Severe anemia can rarely be a presenting symptom of chronic uterine inversion. Following a surgical procedure for chronic uterus inversion, a successful delivery is possible if thorough follow-up is carried out.

Pure Red Cell Aplasia Encountered in a Tertiary Care Hematology Laboratory: A Series of Nine Distinctive Cases.

Pure red cell aplasia (PRCA) is characterized by severe anemia with reticulocytopenia and bone marrow erythroblastopenia. The early erythroblasts are markedly decreased; however, in rare instances, they may be normal or raised in number. There are varied etiologies, namely congenital or acquired and primary or secondary. The congenital PRCA is known as "Diamond-Blackfan anemia." Thymomas, autoimmune disease, lymphomas, infections, and drugs also may be familiar associates. However, the etiologies of PRCA are numerous, and many diseases/infections can be associated with PRCA. The diagnosis rests on clinical suspicion and appropriate laboratory workup. We evaluated nine cases of red cell aplasia, having severe anemia with reticulocytopenia. Nearly half of the cases showed adequate erythroid (> 5% of the differential count) but with a maturation arrest. The adequacy of the erythroid could confuse the hematologist and may even delay the diagnosis. Hence, it is empirical that PRCA could be considered a differential in every case of severe anemia with reticulocytopenia, even in the presence of adequate erythroid precursors in the bone marrow.

Molecular characterization and pathogenicity study of a highly pathogenic strain of chicken anemia virus that emerged in China.

Chicken infectious anemia (CIA) is caused by chicken anemia virus (CAV). Recently, severe anemia has emerged in layer chickens (8 to 10-week-old) on poultry farms in China. However, the etiological characteristics and pathogenic potential of CAV in chickens at 6 weeks or older are not well understood. In this study, we isolated a CAV strain, termed SD15, from two-month-old chicken with severe anemia and analyzed the genetic evolution relationship. We found that strain SD15 had the highest homology (98.9%) with CAV18 strain. Comparison with 33 reference strains revealed 16 amino acid mutations in strain SD15, two of which were previously unknown (F210S in VP1 and L25S in Vp3). Compared with low pathogenic strains (Cux-1 and C14), highly pathogenic strains (SDLY08 and SD15) had three base mutations in their noncoding region. To further understand its pathogenicity, 10-week-old specific-pathogen-free (SPF) chickens were challenged with the novel strain and SDLY08. No obvious clinical symptoms were observed in the SDLY08 group. However, SD15-infected chickens showed significant growth retardation and immunosuppression. The main manifestations of immunosuppression were the significantly reduced thymus and bursa indices and AIV-H9 vaccine-induced antibody levels (P < 0.05). The lowest number of red blood cells in the SD15 group was just 60% of that in the control group. Taken together, the novel strain SD15 not only showed higher pathogenicity but also exhibited the potential ability to break the age resistance of older chickens to CAV. Our study enhanced the understanding of the epidemiological characteristics of chickens infected with severe anemia and can facilitate the development of improved control strategies of CIA in China.

Quantifying pulse oximeter accuracy during hypoxemia and severe anemia using an in vitro circulation system.

Anemia and hypoxemia are common clinical conditions that are difficult to study and may impact pulse oximeter performance. Utilizing an in vitro circulation system, we studied performance of three pulse oximeters during hypoxemia and severe anemia. Three oximeters including one benchtop, one handheld, and one fingertip device were selected to reflect a range of cost and device types. Human blood was diluted to generate four hematocrit levels (40%, 30%, 20%, and 10%). Oxygen and nitrogen were bubbled through the blood to generate a range of oxygen saturations (O2Hb) and the blood was cycled through the in vitro circulation system. Pulse oximeter saturations (SpO2) were paired with simultaneously-measured O2Hb readings from a reference CO-oximeter. Data for each hematocrit level and each device were least-squares fit to a 2nd-order equation with quality of each curve fit evaluated using standard error of the estimate. Bias and average root mean square error were calculated after correcting for the calibration difference between human and in vitro circulation system calibration. The benchtop oximeter maintained good accuracy at all but the most extreme level of anemia. The handheld device was not as accurate as the benchtop, and inaccuracies increased at lower hematocrit levels. The fingertip device was the least accurate of the three oximeters. Pulse oximeter performance is impacted by severe anemia in vitro. The use of in vitro calibration systems may play an important role in augmenting in vivo performance studies evaluating pulse oximeter performance in challenging conditions.