pRBC Units Research Articles

VNOTES (vaginal natural orifice transluminal endoscopic surgery) staging of endometrial cancer with sentinel lymph nodes (551)

VNOTES (vaginal natural orifice transluminal endoscopic surgery) staging of endometrial cancer with sentinel lymph nodes (551)

Machine learning-based prediction of massive perioperative allogeneic blood transfusion in cardiac surgery.

Massive perioperative allogeneic blood transfusion, that is, perioperative transfusion of more than 10 units of packed red blood cells (pRBC), is one of the main contributors to perioperative morbidity and mortality in cardiac surgery. Prediction of perioperative blood transfusion might enable preemptive treatment strategies to reduce risk and improve patient outcomes while reducing resource utilisation. We, therefore, investigated the precision of five different machine learning algorithms to predict the occurrence of massive perioperative allogeneic blood transfusion in cardiac surgery at our centre. Is it possible to predict massive perioperative allogeneic blood transfusion using machine learning? Retrospective, observational study. Single adult cardiac surgery centre in Austria between 01 January 2010 and 31 December 2019. Patients undergoing cardiac surgery. Primary outcome measures were the number of patients receiving at least 10 units pRBC, the area under the curve for the receiver operating characteristics curve, the F1 score, and the negative-predictive (NPV) and positive-predictive values (PPV) of the five machine learning algorithms used to predict massive perioperative allogeneic blood transfusion. A total of 3782 (1124 female:) patients were enrolled and 139 received at least 10 pRBC units. Using all features available at hospital admission, massive perioperative allogeneic blood transfusion could be excluded rather accurately. The best area under the curve was achieved by Random Forests: 0.810 (0.76 to 0.86) with high NPV of 0.99). This was still true using only the eight most important features [area under the curve 0.800 (0.75 to 0.85)]. Machine learning models may provide clinical decision support as to which patients to focus on for perioperative preventive treatment in order to preemptively reduce massive perioperative allogeneic blood transfusion by predicting, which patients are not at risk. Johannes Kepler University Ethics Committee Study Number 1091/2021, Clinicaltrials.gov identifier NCT04856618.

Low Volume Blood Product Transfusion Patterns And Ratios After Injury

BackgroundThe benefit of a balanced resuscitation in low volume transfusions remains unclear This study is aimed at characterizing blood product ratios in this cohort. MethodsA retrospective analysis (2017–2019) of the ACS TQIP was performed to identify adult trauma patients who received ≥1 unit of packed red blood cells (pRBCs) 4 and 24 h after admission. Blood products received were used to calculate plasma and platelet ratios. ResultsPlasma and platelet ratios were closer to the target 1:1 ratio for ≤4 units pRBCs. Plasma and platelet ratios increased for those receiving ≤10 units pRBCs, demonstrating increasingly unbalanced resuscitation. Transfusion ratios were unbalanced for those receiving ≥5 units pRBC. ConclusionTransfusion ratios were closer to the desired transfusion ratio for low volume blood product resuscitation. In those receiving ≥5 units pRBC, plasma and platelet ratios were not balanced. The optimal transfusion ratio in low volume trauma resuscitation is unknown.

P1465: INITIAL SAFETY AND EFFICACY STUDY OF RM-001, AUTOLOGOUS HBG1/2 PROMOTER-MODIFIED CD34+ HEMATOPOIETIC STEM AND PROGENITOR CELLS, IN TRANSFUSION-DEPENDENT ΒETA-THALASSEMIA

Background: Natural mutations that cause hereditary persistence of fetal hemoglobin (HPFH) alleviate the symptoms of β-thalassemia. It is now known that small natural deletions and mutations in the γ- globin gene (HBG1/HBG2) promoters disrupt the binding of the transcriptional repressors BCL11A, causing HPFH. Using gene editing to mimic these mutations should reactivate γ- globin in patients with transfusion-dependent β-thalassemia (TDT) and ameliorate the debilitating effects of mutations in β-globin. Aims: To induce HbF production in erythrocytes, we used ex vivo CRISPR-Cas9–based gene editing to modify HBG1/HBG2 promoter in hematopoietic stem and progenitor cells (HSPCs), producing RM-001. We initiated initial safety and efficacy study of RM-001 in TDT patients. Here, we present initial results from the first 2 patients treated with RM-001. Methods: Patients (6–35 y of age) with TDT receiving packed red blood cell (pRBC) transfusions of ≥100 mL/kg/y or ≥10 units/y in the previous 2 y were eligible. Peripheral CD34+ HSPCs were collected by apheresis after mobilization with G-CSF and plerixafor. CD34+ cells were edited with CRISPR-Cas9 using a guide RNA specific for the binding site of BCL11A on the HBG1/HBG2 promoter. Prior to RM-001 DP infusion, patients received myeloablative conditioning with Busulfan from day-7 to day-3. Patients were monitored for stem cell engraftment/hematopoietic recovery, adverse events (AEs), Hb production, HbF and F-cell expression, pRBC transfusion requirements. Results: Data presented here for the first 2 TDT patients treated with RM-001. Both patients have β0/β0 genotype (CD17/CD41-42, CD41-42/CD41-42), with an annualized packed red blood cell (pRBC) transfusion history of 39 units/y and 54.8 units/y over 2 y prior to consent, respectively. Both patients received a single dose of RM-001 cells, ceased pRBC transfusions within 1 month after RM-001 infusion and remained transfusion-free through the reported period. The first patient (CD17/CD41-42, 9y) achieved neutrophil and platelet engraftment on Day(D+)19 and D+21; the other (CD41-42/CD41-42, 13y) achieved neutrophil and platelet engraftment on D+16 and D+21, respectively. No serious adverse event (SAE) occurred. The safety profile was generally consistent with busulfan myeloablation and autologous hematopoietic stem cell transplantation. Total Hb, HbF and F-cell percentage increased over time in both patients (Figure). Both patients received 6 units of pRBC before transfusion independent (TI) achieved (Hb stably ≥ 90g/L), with last pRBC transfusion on D+15 and D+28, respectively. The first patient achieved TI on D+28 and the other achieved TI on D+39. At 3 month post-RM-001 infusion, total Hb exceed 110 g/L in both patients, with 97-98 g/L HbF. Approximately 89% peripheral erythrocytes are F-cells at 3 month post-RM-001 infusion (Figure). Data will be updated for the presentation. Image:Summary/Conclusion: The first 2 patients treated with RM-001 demonstrated successful engraftment and both have been transfusion free within two month. Although both patients have β0/β0 genotype, they ceased pRBC transfusions within 1 month after RM-001 infusion and remained transfusion-free through the reported period. This is the first-in-human study of autologous HBG1/2 promoter-modified CD34+ HSPCs (RM-001) in TDT and both patients were treated successfully without SAE. Our studies provide novel and initial clinical evidence supporting the safety and efficacy of RM-001 for treating TDT.

Impact of blood donor characteristics on quality of packed red blood cell concentrates.

Impact of blood donor characteristics on quality of packed red blood cell concentrates. To determine the impact of donor factors on the quality of packed red blood cell concentrates. The analytical cross sectional study was conducted on 505 whole blood donors after approval by the Institutional Ethics Committee and written informed consent from blood donors. Two mL EDTA sample was collected for pre-donation haemoglobin estimation and all relevant donor details were recorded. Whole blood was collected in 350mL double blood bags. PRBCs were prepared as per the departmental SOP. Volume of each PRBC was recorded and sample from each bag was taken for estimation of total haemoglobin content and haematocrit. Of 505 blood donors, 459 (90.9%) were males and 324 donors (64.2%) were less than 30 years of age. The majority of the donors were repeat donors (61%, n=308 repeat donors), vegetarians (52.9%, n=267 vegetarians) and non-smokers (92.7%, n=468). Mean haemoglobin was found to be significantly higher in males (14.9 vs. 13.3; P≤0.001), donors more than 30 years of age (15 vs. 14.7; P=0.042), repeat donors (14.9 vs. 14.7), non-vegetarians (15.1 vs. 14.6; P≤0.001) and smokers (15.3 vs. 14.8g/dL; P=0.020). PRBC units prepared from male blood donors, repeat donors and non vegetarians had significantly higher mean volume and mean total haemoglobin content. Strong positive correlation was observed between haemoglobin of the blood donor and total haemoglobin content of the PRBC and volume of blood collected. Donor characteristics do have effect on total haemoglobin content of packed red blood cells.

The influence of leukoreduction on the acute transfusion‐related complication rate in 455 dogs receiving 730 packed RBCs: 2014–2017

To investigate the influence of prestorage leukoreduction of packed RBCs (pRBCs) on acute transfusion-related complication rate in dogs. Two private referral hospitals. Retrospective case study. Four hundred and fifty-five dogs receiving nonleukoreduced (nLR) or leukoreduced (LR) pRBC between January 1, 2014 and July 31, 2017. Transfusions were retrospectively reviewed to record data about the patient, donor, unit, transfusion event, acute complications, hospital discharge, and cause of death. Of 730 transfusion events in 455 dogs, 288 used LR pRBC and 442 used nLR pRBC. There was a 18.9% (138/730) overall complication rate. Seven (0.96%) complications were life-threatening. The most common complications were pyrexia (5.6%), gastrointestinal signs (4.9%), and hemolysis with no other signs (4.1%). Pyrexia with no other clinical signs, consistent with a febrile nonhemolytic transfusion reaction (FNHTR), occurred in 3.2% of transfusion events. There was a significant (P=0.03) decrease in the rate of FNHTR with LR pRBC (1%) versus nLR pRBC (4.5%). Use of LR pRBC did not decrease in-hospital mortality. The odds of any complication, hemolysis only, FNHTR, and more severe complications increased with pRBC age. Leukoreduction did not decrease the impact of pRBC age on these complications. Use of older pRBC did not increase the incidence of life-threatening complications or mortality. Dogs receiving pRBC for blood loss were more likely to have gastrointestinal and more severe complications than those dogs that had hemolysis. The effect of pRBC unit age on complications was not influenced by the underlying reason for transfusion. Dogs that received a previous transfusion were more likely to have respiratory complications. In this study, the use of LR pRBC was associated with a decreased rate of FNHTR but no other complications. Unit age was associated with the incidence of hemolysis, FNHTR, and complication severity but not the rate of life-threatening complications or mortality.

Spectrum of clinically significant anti-M antibody in patients requiring transfusion

Aims: The study aimed to determine the frequency and serological characteristics of anti-M antibody in patient population. Methods: It was a retrospective study over for a period of two years (April, 2016 to March, 2018). Blood grouping was performed by tube technique. In case of incompatible cross-match, antibody screening and identification were performed using LISS Coombs’ anti-human globulin (AHG) gel cards (Bio-Rad, Switzerland). Di-thiothreitol (DTT) treatment was also performed to demonstrate the existence of a potentially clinical significant IgG antibody. Results: The frequency of anti-M antibody was 0.05% in patients (51 out of 101,364 requisitions). DTT treatment could be done in 12 samples which showed it was IgM type in 11 (91.7%) and mixture of IgM and IgG type in 1 (8.3%) case. Transfusion history was present in 21 (41.2%), absent in 13 (25.5%), and not known in 17 (33.3%) patients. M antigen phenotyping in 42 patients showed that 41/42 patients were M-negative (six of them gave a “mixed-field” agglutination due to recent transfusion of M+ PRBC unit). The 42nd patient was typed as M+ which could be again due to history of recent transfusion of PRBC. Conclusion: Most of the anti-M antibodies were IgM type, however, serological characterization revealed the IgG type also which were found to be reactive at 37°C in AHG phase and thus clinically significant.

The effect of position and frequency of mixing on canine packed red blood cell units during storage.

Hemolysis is an indicator of storage lesion that occurs in stored packed red blood cells (pRBCs) over time. Intermittent mixing of red blood cells in the additive solutions may be beneficial but may also result in iatrogenic injury. Position of units in storage may also affect the quality of the pRBCs. This prospective study was designed to evaluate hemolytic effect of mixing frequency and storage position on canine pRBCs over a period of 28days. Prospective in vitro study SETTING: Private practice referral hospital with an internal blood bank ANIMALS: Thirty-two healthy prescreened dogs enrolled in a volunteer blood banking program INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: A total of 160 samples were evaluated. Forty canine pRBC units were split into 4 daughter bags and stored in varying positions with different mixing frequencies. Samples were stored upright and mixed daily, upright and mixed weekly, horizontally and mixed daily, or horizontally and mixed weekly for a period of 28days. At days 0, 7, 14, and 28, samples from the units were analyzed to calculate percent hemolysis. No differences were found in any hemolytic indicators investigated (total hemoglobin, free plasma hemoglobin, and packed cell volume) until day 28 in all test groups. Canine pRBCs stored upright and mixed weekly or stored horizontally and mixed weekly resulted in less hemolysis and free plasma hemoglobin when compared to units stored horizontally and mixed daily only at day 28. Statistically significant hemolysis was not evident amongst canine pRBC groups less than 28days old suggesting that positioning and mixing frequency was irrelevant until day 28. Beyond 28days despite the presence of hemolysis, no definitive recommendation could be made with respect to best practice for storage position or mixing frequency of stored canine pRBCs.

Drills or Simulation Exercises for Postpartum Hemorrhage: A Systematic Review and Bayesian Meta-Analysis

The Joint Commission and national guideline proscribes drills or simulation exercise (DSE) to mitigate the morbidity and mortality (M&M) associated with postpartum hemorrhage (PPH). The objective of this analysis was to compare the maternal outcomes associated with PPH before and after introduction of DSE. The co-primary outcomes were the rate of PPH or of any transfusion; the secondary outcomes included admission to the intensive care unit (ICU), transfusion ≥ 4 units PRBC, hysterectomy or maternal death.

Hyperhemolysis in the Setting of Mixed-Autoimmune Hemolytic Anemia: A Rare Complication of COVID-19

SARS-CoV-2 is a novel human pathogen known for its predilection for the respiratory system. Herein, we present a unique case in which a patient developed hyperhemolysis in the setting of mixed autoimmune hemolytic anemia secondary to SARS-CoV-2. A 33 years-old male with a past medical history of resolved immune thrombocytopenic purpura (ITP) presented to the hospital with symptoms of jaundice after being infected with SARS-CoV-2. On admission, his Hgb was 12.5g/dL. Lab results showed indirect bilirubin of 13mg/ dL, LDH at 759 U/L, Haptoglobin <10 and the percent reticulocyte count was 2.33%. A DAT was also positive for C3, IgG, anti-E, in addition to both warm and cold autoantibodies. PCR was positive for COVID-19. Within two days of admission, his Hgb dropped to 5.9g/dL. A total of seven units of pRBC was required to achieve an Hgb of 6g/dL in 48 hours. Patients with preexisting hematological abnormalities have a propensity to develop AIHA in the setting of the virus. The majority of the cases described in the literature were associated with warm autoimmune hemolytic anemia. Our patient tested positive for both warm and cold antibodies, which may partially explain the mechanism behind hyperhemolysis in our patient.

Successful Use of Plasma Exchange Preceding RBC Exchange in Sickle Cell Disease Hyperhemolytic Crisis with Hepatic Sequestration: A Case Report

IntroductionHyperhemolytic crisis is an uncommon complication of SCD that may cause multiorgan failure and lead to significant mortality. There are no current national or international guidelines for management of hyperhemolytic crisis and associated complications. There have been limited number of case reports and series that demonstrated utility of plasma exchange in the patients with multiorgan failure resulting from hemolysis complications (Zaidi GZ et al.,2020). We are presenting the case where hyperhemolytic crisis was complicated by hepatic sequestration and acute liver failure, that was dramatically reversed by 2 plasma exchange treatments followed by RBC exchange.Case reportWe present a case of a 35-year-old African American male with SCD and beta thalassemia trait with frequent hospitalizations for sickle cell pain crisis. He presented with pain typical for his acute pain crises and was admitted for intravenous hydration and pain control. The next morning, lab work showed bicytopenia with a drop in hemoglobin from 10.5 to 5.8 g/dL and platelets (PLT) from 100 to 22 X10E3/uL. Lactate dehydrogenase (LDH) increased from 434 to 2848 U/L, haptoglobin was 36 mg/dL, but disseminated intravascular coagulation (DIC) and Heparin-induced Thrombocytopenia (HIT) antibody panel were negative. The blood urea nitrogen (BUN) creatinine (Cr) ratio was also elevated (30.6) suggesting renal damage as well. He was transferred to the intensive care unit and started on Intravenous Immunoglobulin (IVIG) 0.4 grams/kilogram daily for 5 days and methylprednisolone 500 mg daily for 2 days followed by a prednisone taper. Liver enzymes continued to trend upward with AST of 19,866 U/L and ALT of 3,675 U/L on day 3 of hospitalization. Ultrasound of abdomen demonstrated mild splenomegaly with a spleen measuring 13.3 cm. The clinical presentation and hepatocellular pattern of injury was consistent with hepatic sequestration crisis. Despite receiving 1 unit of platelet 3 units of pRBC, there was little improvement and apheresis service was consulted. Plasma exchange was initiated for 2 procedures on consecutive days followed by RBC exchange with rapid improvement in clinical status and laboratory findings with a reduction of LDH (1304), AST (129), ALT (204), Hgb (8.0), PLT (41), BUN/Cr (20.0). He was discharged on day 7 at baseline status.DiscussionAlthough the mechanism of development of hyperhemolysis in SCD is not fully understood, the hemolysis leads to release of free hemoglobin (Hb) and free heme that activate neutrophils, and vascular endothelial cells via TLR-4. This ultimately leads to inflammatory, coagulative, and cytotoxic damages and decreased nitric oxide (NO) bioavailability which further contributes to SCD complications such as pulmonary and systemic vasculopathy, pain crisis and acute chest syndrome and multi organ failure (Louie JE et al., 2018). This provides a rationale for plasma exchange - removal of free heme from the patient plasma and replenishing exhausted haptoglobin and hemopexin reserves from donor plasma.Hemolytic crisis causing visceral organ damage is relatively rare. There are no current guidelines for management of such patients. In 1996 Betrosian et al. discussed the first case of liver failure in a SCD with vasa-occlusive crisis treated with RBC and plasma transfusions (Betrosian A et al., 1996). Since then, there have been case reports/series of plasma exchange/plasma transfusions in SCD with multi organ failure (Geigel EJ et al., 1997, Louie JE et al., 2018) but reports about use of plasma exchange in SCD patients with hepatic sequestration have not been identified by our literature review.Our case demonstrates that plasma exchange in hyperhemolysis and hepatic sequestration is: •Safe•Leads to quick and significant improvement in hemolysis laboratory values.•Results in quick and durable reversal of hepatic sequestration and associated liver failure.•Adds plasma exchange as therapeutic apheresis modality in addition to previously accepted RBC exchange.•Provides data about priority of plasma exchange over RBC exchange in this clinical situation. DisclosuresNo relevant conflicts of interest to declare.

S3713 Pre-Pyloric Gastric Ulcer Leading to Stenosed Pylorus, Obstruction of Gastric Outlet and Pseudo-Gastroparesis

Introduction: Gastric outlet obstruction (GOO) is a syndrome manifested with combination of early satiety, abdominal pain, postprandial vomiting and weight loss. The usual etiology is either mechanical (benign or malignant) or motility related. Most common cause of benign obstruction is peptic ulcer disease. Here we discuss a case of pre-pyloric ulcer with significant stenosis that mimics gastroparesis causing acquired GOO. Case Description/Methods: 58 year old female with history of migraines, anxiety and chronic pain presented with generalized weakness and epigastric pain. She had been taking 2 pills of aspirin and Advil each every 3 hours for past 2 weeks for her toothache. She also reported melanotic stools. In the ER, she was vitally stable but had hemoglobin of 5.5. CTA of abdomen pelvis noted abnormal duodenum with diffuse mural thickening and mildly prominent lymph nodes. She was transfused 2 units of PRBC. EGD done revealed linear antral ulcer occupying two-thirds of pre-pyloric area measuring 4 cm extending into the pylorus with minimal oozing on contact. Pylorus was severely narrowed and ulcerated; it could not be traversed with adult scope. XP scope was then used which passed with ease through the pylorus into the duodenal bulb which appeared to be severely ulcerated. Rest of the duodenum was normal. Patient subsequently had Gastrografin follow through study to evaluate for gastric outlet obstruction which showed suspected mild stenosis &/or edema in pylorus secondary to ulcerative dislocation; however no bowel obstruction was noted since the contrast passed through the duodenum. Biopsy ruled out malignancy & H. pylori infection and was consistent with chemical gastropathy. Gastrin level was also noted to be normal. Patient was on placed on clear liquid diet initially and later transitioned to full liquids since she was unable to tolerate solid foods. She had a repeat EGD 4 weeks later while on Pantoprazole 2 times daily and eventually showed partial resolution of ulcerated lesions. Discussion: Pre-pyloric ulcers are the most common form of peptic ulcer disease leading to GOO. Most common site is the pyloric channel or duodenal bulb which was the case in our patient. Acute ulcers usually cause inflammation and edema that leads to tissue deformation and obstruction especially with solid food particles getting lodged into the ulcer. Despite these, obstruction usually occurs in 2% of the cases of peptic ulcer disease and is the least common complication contributing to gastroparesis like symptoms.Figure 1.: Figure 1). Pre-pyloric stomach ulcer 2). Pre-pyloric stomach ulcer 3). Pylorus with food residue/Bezoar stuck in the stenosed pylorus 4). Pre-pyloric stomach ulcer after 4 weeks of Protonix therapy 5). Ulcer at 11-1 o clock 6). Ulcer at 12 o clock.

S2384 Recurrent GI Bleeding From Colo Pancreatic Fistula – A Rare Entity

Introduction: Acute pancreatitis is an acute inflammatory condition affecting the pancreas. Colonic complications rarely occur with acute and chronic pancreatitis. Localized ileus, obstruction, colonic ischemia, hemorrhage and fistula formation have been reported together with acute pancreatitis. Colo-pancreatic fistula occurs at a rate of 3% to 10% in patients with severe acute pancreatitis. Here, we discuss the case of a patient with recurrent GI bleeding from a colo-pancreatic fistula. Case Description/Methods: A 62-year-old White male with past medical history of COPD, CAD s/p PCI, history of paroxysmal atrial fibrillation on Eliquis, diabetes presented with complaints of bleeding per rectum. He denied any other complaints. MRI abdomen showed pancreatic pseudocyst with possible fistulization of the pancreatic pseudocyst to the proximal descending colon (Fig 1A). Patient underwent EGD and colonoscopy. Colonoscopy showed evidence of pancreatico enteric fistula distal to the splenic flexure, the remnants were cleared on lavage and patient was discharged once stable (Fig 1B). One month later patient presented with another episode of recurrent GI bleeding he required 2 units of PRBC given the prior findings on the colonoscopy, patient was referred to pancreatic surgeon for further intervention of the colo-pancreatic fistula. Discussion: CPF is a rare condition associated with high mortality in patients with acute pancreatitis. Abdominal CT with or without contrast is often used for diagnosis; however, colonoscopy is also used to detect CPF. Given the anatomical proximity of the left part of the colon to the pancreas, CPF is commonly seen on the left side. Patients present with symptoms such as nausea, abdominal pain, vomiting and gastrointestinal bleeding. In contrast to other pancreatic enteric fistulas, CPF is associated with a high risk of severe hemorrhage, perforation or infection. Unlike other pancreatic enteric fistulas CPF do not close spontaneously, surgery is often the recommended treatment; however, less invasive endoscopic interventions, such as those using conventional hemoclips or over the scope clip, have been reported to have successful outcomes.Figure 1.: Fig 1A: MRI Abdomen showing pancreatic pseudocyst (shown by two blue arrows). Fig 1B: Colonoscopy showing fistulous opening in the descending colon distal to splenic flexure (shown by black arrow).

S3073 A Rare Cause of Repeat Hemorrhage: When Cytomegalovirus Hides in the Small Bowel

Introduction: Cytomegalovirus (CMV) is an opportunistic infection typically seen in immunocompromised patients, like those with Human Immunodeficiency Virus (HIV) or organ and stem cell transplant recipients. CMV infections are exceedingly uncommon in the immunocompetent duodenum. We describe such a case, confirmed with biopsy and complicated by severe repeated gastrointestinal hemorrhage. Case Description/Methods: A 74-year-old male with PMH of diabetes, bladder cancer (status-post resection and ureteral stent placement), presented to the ED with general malaise. Was found to meet sepsis criteria and was anemic with bright red blood on rectal exam. CT abdomen and pelvis revealed multiple pelvic abscesses and free air. Stool testing was positive for C. diff and oral vancomycin and IV zosyn were started. Patient was admitted to telemetry and required 3 separate units pRBC for persistent anemia. CTA abdomen performed on day 3 revealed a duodenal bleed. IR performed an embolization, however, patient remained unstable and required intubation and pressors. Anemia continued to worsen, and patient received an additional 2 units pRBC. GI performed a bedside EGD revealing a large clot and duodenal ulcer. Sepsis continued to worsen, and antibiotics were broadened to meropenem and vancomycin. Anemia continued to worsen, and an additional EGD was performed with source control reported. Patient was extubated, and shortly thereafter, had melena, so a final EGD was performed, identifying friable mucosa and a bleeding duodenal vessel. Hemospray and a clip were deployed to contain bleeding, and the patient received a seventh unit of blood. Biopsied duodenal tissue stain showed CMV (Figure 1A) and histology revealed inclusions (Figure 1B), so ganciclovir was started. Recurrent bleeding subsequently resolved, and patient was discharged to subacute rehabilitation to complete a course of IV ganciclovir. Discussion: Though rare in immunocompetent patients, CMV infections should be considered in severe or persistent gastrointestinal bleeds. CMV duodenitis, while very uncommon, has been documented in case reports and is associated with ischemia and massive hemorrhage. In this case, the patient ultimately required seven units of blood, intubation, and numerous endoscopic procedures as a result of CMV duodenitis. Clinical improvement was seen only once the underlying infection was treated and illustrates the need to consider CMV infection in the differential for recurrent gastrointestinal bleeding.Figure 1.: A: Immunohistochemical stain of tissue from duodenal biopsy identifying CMV. B: Histology of duodenal tissue biopsy under high power showing CMV inclusions.

S654 Comparative Analysis of Pre-endoscopy Intravenous Erythromycin versus Nasogastric Lavage and Combination of Both in Acute Upper GI Bleeding: A Systemic Review and Meta-Analysis

Introduction: The diagnostic and therapeutic value of EGD in patients with acute UGIB is often limited by the presence of residual blood or clots. Prokinetic agents such as erythromycin or metoclopramide, or a nasogastric (NG) lavage are utilized to improve visualization upper GI tract. We conducted a systemic review and meta-analysis to find which is superior to achieve a satisfactory gastric visualization using either IV erythromycin or NG gastric lavage, or both Methods: We conducted a systematic search of the PubMed database from inception through May-2016 for studies comparing erythromycin, nasogastric lavage, and a combination of both in acute UGIB. Utilized terms were either “erythromycin”, “nasogastric lavage, or NG lavage and erythromycin”, “acute UGIB”. The primary endpoint was satisfactory stomach visualization (SSV) and secondary endpoints were identified as the frequency of repeat endoscopy, units of PRBC transfused, duration of endoscopy in minutes, mortality at 24 hours, and rebleeding rate. Relevant data were extracted and analyzed using Comprehensive Meta-Analysis software. The random-effects model was used for all variables, and publication bias was assessed using Egger’s test Results: Five randomized controlled trials and prospective studies published between 2002 and 2016, with a total of 541 patients, were included in our analysis. The patient’s pool presented with hematemesis or melena, whether it was variceal or non-variceal bleeding. We identified IV erythromycin to be superior to NG lavage alone regarding SSV with relative ratio of 1.338 (95% CI 1.006 to 1.780) (I2=67.984%), no difference between IV erythromycin alone versus a combination of IV erythromycin and NG lavage regarding the same primary endpoint with the relative ratio of 0.971 (95% CI 0.887 to 1.063) (I2=0.000%). We also identified no significant difference between intravenous erythromycin and nasogastric lavage alone regarding secondary endpoints as mentioned above with relative ratios of 0.713 (95% CI 0.434 to 1.171) (I2=21.960%), 0.762 (95% CI 0.303 to 1.920) (I2=0.000%), 1.052 (95% CI 0.778 to 1.424) (I2=0.000%), 1.482 (95% CI 0.254 to 8.643) (I2=0.000%) and 0.776 (95% CI 0.301 to 2.004) (I2=0.000%) respectively Conclusion: Our results suggest that IV erythromycin alone is superior to NG lavage alone and a combination of IV erythromycin and NG lavage in acute UGIB Using IV erythromycin alone has better outcomes regarding satisfactory stomach visualization and can enhance the quality of upper GI tract preparation.

Risk Factors for Abdominal Compartment Syndrome After Endovascular Repair for Ruptured Abdominal Aortic Aneurysm: A Case Control Study

Ruptured abdominal aortic aneurysms (rAAA) are treated by endovascular aneurysm repair (rEVAR) increasingly often. Despite rEVAR being a minimally invasive method, abdominal compartment syndrome (ACS) remains a significant post-operative threat. The aim of this study was to investigate risk factors for ACS after rEVAR, including aortic morphological features. The Swedish vascular registry (Swedvasc) was assessed for ACS after rEVAR in the period 2008 - 2015. All patients identified were compared with controls (i.e., patients who did not develop ACS after rEVAR), matched by centre and repair date. Case records were reviewed, and radiology images analysed in a core laboratory. Comparisons were performed with respect to physiological and radiological risk factors. The study population consisted of 40 patients with ACS and 68 controls. Pre-operatively, patients with ACS had a lower blood pressure (BP) than controls (median 70 mmHg vs. 97 mmHg; p < .001). Intra-operatively, they had aortic balloon occlusion more often (55.0% vs. 10.3%; p < .001) and received more transfusions than controls (median nine units of packed red blood cells [pRBC] vs. two units; p < .001). Ninety-seven per cent of those who developed ACS had a pre-operative BP < 70 mmHg, aortic balloon occlusion, or received more than five pRBC unit transfusions. Treatment outside the instructions for use did not differ between patients and controls (57.5% vs. 54.4%; p= .84), and neither did the pre-operative patency of the inferior mesenteric artery (57.1% vs. 63.9%; p= .52) nor the number of visible lumbar arteries on pre-operative imaging (2 vs. 4; p= .014). In multivariable logistic regression, the number of intra-operative transfusions were predictive of ACS (p < .001), while pre-operative hypotension (p= .32) and aortic balloon occlusion (p= .018) were not. ACS after rEVAR is mainly associated with physiological factors and is unlikely to develop without the presence of a pre-operative BP < 70 mmHg, the need for an aortic occlusion balloon, or more than five intra-operative pRBC unit transfusions. Treatment outside the IFU or any other morphological factor were not associated with a risk of ACS.

Alloimmunization to Erythrocyte Antigens in Patients Receiving Multiple Blood Transfusions

Background and Objectives: The risk of red blood cell (RBC) alloimmunization is always a concern for multi-transfused patients. Various factors have been found to be associated with alloimmunization. Alloimmunization rates were reported from 4% to 50%, 1.9% to 13% and 1.27% to 13.1% in thalassemic, onco-hematology and renal patients respectively. Transfusion of extended phenotype-matched blood was found to reduce rate of alloimmunization. This study investigated the various risk factors associated with RBC alloimmunization and the impact of transfusing phenotype-matched PRBC to multi-transfused patients. Methods: The retrospective observational study included 4350 multi-transfused patients of hemoglobinopathies, onco-hematological diseases and chronic renal failure (CRF). Pre-transfusion testing that included ABO and Rh(D) typing, antibody screening and crossmatching were performed following departmental standard operating procedure (SOP). Rh (C, c, E, e) and Kell (K) antigen phenotyping of blood donors as well as patients were performed by recommended techniques. Statistical analysis was done using the SPSS statistical package. Results: The mean age of multi-transfused patients was 41.4 years with a female preponderance. A total of 122 alloantibodies with various specificities were found in the 4350 patients (2.8%). Anti-E was the most frequent alloantibody (27.87%) followed by anti-c (11.48%). Frequency of alloimmunization in patients with hemoglobinopathies receiving phenotype-matched blood was 1.89% which was significantly lower than those receiving phenotype-unmatched blood (p=0.0019). Gender, age, splenomegaly status, number of PRBC unit transfused, phenotype-matched status, and transfusion duration in years were independent risk factors of alloimmunization. Conclusion: Alloimmunization to red blood antigens challenge the proper management of multi-transfused patients. Based on the present results we suggest considering antibody screening as an important tool of pre-transfusion testing to ensure safe blood transfusion. It will be prudent to adopt a transfusion policy that provides at least the Rh-Kell phenotype-matched blood to minimize red cell alloimmunization among multi-transfused patients.

Transfusion Associated Circulatory Overload in Ambulatory Transfusions

Introduction: Transfusion Associated Circulatory Overload (TACO) is a leading cause of transfusion related adverse events. Existing estimates of TACO incidence are derived from observations in a predominantly inpatient setting, where, incidence estimates range from 1 to 8% of transfusions (Bachowski G, et al. A Compendium of Transfusion Practice Guidelines Third Edition 2017: American Association Blood Banks). This is the first report of incidence and risk factors for TACO in ambulatory transfusions.Methods: A retrospective cohort analysis of ambulatory patients transfused in a tertiary haematology centre was undertaken in a 12 month period between January to December 2014. Electronic medical records, electronic transfusion database, and patient notes were utilized to obtain data. Variables included age, gender, haematological diagnosis, documented congestive heart failure (CHF) or chronic kidney disease (CKD), details of transfusion encounter, and post transfusion medical review. For the purpose of this study, TACO was defined as documented evidence of hypervolaemia on clinical review and/or if otherwise unplanned diuretic therapy was prescribed for symptoms/signs of fluid overload.Logistic regression models were used to measure associations between TACO events and patient covariates, using cluster-robust Huber-White standard errors to account for the repeated observations on patients. Variables were selected for entry into the statistical models based on a review of existing evidence. Statistical analyses were programed using Stata v13.0 (StataCorp Ltd, College Station, Tx) and was approved by institutional ethics committee.Results: A total of 812 transfusion encounters in 94 ambulatory patients (male=50, female=44), with a mean age of 76 ±11.3 years was observed. The most common underlying haematological diagnoses included myelodysplasia, myelofiborisis, acute leukemia, (table 1). At baseline, 11.2% (14/94) and 13.6% (17/94) of subjects had documented history of CHF and CKD (table 1).There was a total of 1723 packed red cell units (PRBC) transfused across the 812 ambulatory transfusion encounters. The median number of units transfused was 2 per encounter (range 1-4) and median cumulative number of transfusions received per patient was 7 (range 1-28) over the study period. TACO was observed in 7.03% of all transfusion encounters (a total of 57 events in 32 subjects).No cases resulted in inpatient investigation, management or death.The variables of age, gender, CHF, CKD, PRBC units per encounter, and cumulative units received were assessed in regression models. In a univariate model, age was observed to be significantly associated with TACO, odds ratio=1.048 (p=0.011 95%, CI 1.011-1.086).The remaining variables were not statistically significant predictors of TACO in either univariate or multivariate model and significance for age was not retained in a multivariate model (p=0.06) as shown in table 2.Conclusions: This data confirms TACO is an important consideration in the ambulatory transfusions and occurred in 7.03% of transfusion encounters. This is similar to the range seen in hospitalized patients though it was reassuring that no severe cases were observed. Patient age appeared to be an important risk factor in the univariate model with the odds for TACO increasing with each year. In contrast to hospitalized patients, CHF and CKD did not increase the odds for TACO in multivariate regression models. To our knowledge, this is first study to report on incidence and risk factors for TACO in ambulatory transfusions providing a new perspective on this important aspect of haemovigilance. These results also enable better patient information prior to consenting for transfusions. Our study is limited by the retrospective and single center design, but provides vital baseline data for future prospective studies. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Surrogate Thresholds for Iron Chelation in Patients with Hematological Malignancies

Background: The reference standard for evaluating the magnitude of body iron overload is measurement of the liver iron concentration (LIC). Until recently, the conventional clinical method for measuring LIC was through analysis of biopsy specimens considered the “gold standard” of LIC measurement. To counter the shortcomings of liver biopsy, several noninvasive techniques have been applied to estimate LIC. The spin-density projection-assisted (SDPA) R2-MRI (FerriScan) technique has been recently validated to estimate LIC. There are reports in the literature that ferritin levels in patients with hematological malignancies (HM) may not correlate sufficiently with LIC. We conducted R2-MRI Ferriscan sequencing in consecutive patients with HM followed in our center to better evaluate the diagnostic value of ferritin levels and packed red blood cell (pRBC) transfusions for iron overload.Methods: HM patients with a history of transfusion requirement were evaluated for inclusion in the study within the Liver Iron Cutino Network (Licnet) project. Patients were excluded if they had contraindications to MRI assessment (heart pacemaker, metallic foreign body or devices, and claustrophobia). Demographics and HM disease data were collected, together with ferritin levels and transfusion requirement. R2 LIC measures by FerriScan were defined as indicating normal/marginally high iron load for values 0 to <3, mild liver iron overload for values 3 to < 7, moderate between 7 and 15 and severe if >15. Correlations and the generation of receiver operating characteristic (ROC) curves were performed to test the diagnostic power of ferritin levels and volume of transfused blood (ml/kg in the preceeding 12 months) to indicate moderate-severe iron overload.Results: 28 patients (20 males) of mean age 62, SD 17 years with HM (myelodysplastic syndromes N=14; acute myeloid leukemia N=7, of which 5 post-transplant; acute lymphoblastic leukemia post-transplant N=2; aplastic anemia N=2; non Hodgkin lymphoma N=1; chronic lymphocytic leukemia N=1; erythroblastopenia N=1) were evaluated. Median baseline ferritin levels were 1617 (interquartile range 1185-2360). Mean R2 values were 10.9, SD 10.1 mg/kg. Three patients had normal or marginally high LIC, 12 patients had mild overload, 6 patients moderate and 7 patients severe overload. Both ferritin levels and amount of blood volume transfused in the preceding 12 months correlated well with R2 measures (Spearman rho=0.478, p=0.10 and r=0.509, p=0.006, respectively). However, neither ferritin levels nor transfusions correlated with R2 MRI in patients with normal-mild iron overload while the correlations were confirmed and highly significant in patients with moderate-severe iron overload (r=0.692, p=0.009 and r= 0.754, p=0.003, respectively). ROC curves denied the diagnostic power of ferritin levels and confirmed transfusions to indicate moderate to severe liver iron overload (Figure 1), indicating that 37 ml/kg/year (about 14 units of pRBC) has a sensitivity of 77% and a specificity of 80% to predict moderate-severe iron overloadConclusions: We confirm that, though ferritin levels do generally correlate with LIC, they are not to be considered an appropriate surrogate marker for iron overload in HM. R2 MRI sequencing is valuable to diagnose the state of LIC. The results of this study indicate that as soon as an HM patient begins to receive regular transfusions, since the probability of developing moderate-severe iron overload is high, it is warranted not to await high ferritin levels, nor a large number of pRBC units, to initiate iron chelation. [Display omitted] DisclosuresOliva:Celgene: Consultancy; La Jolla: Consultancy; Amgen Inc.: Consultancy; Novartis: Consultancy; Janssen: Consultancy.

A Retrospective Review of Upper Gastrointestinal Bleed Outcomes During Hospital Admission While on Oral Anticoagulation.

IntroductionDirect-acting oral anticoagulants (DOACs) are approved for stroke prevention in non-valvular atrial fibrillation and treatment of venous thromboembolism. Most recent guidelines recommend DOACs over warfarin for most diagnoses given their predictable pharmacodynamics, lack of required monitoring, and safety profile. Specific outcomes such as shock, acute renal failure, and blood transfusion requirement while on oral anticoagulation compared to no anticoagulation remain unknown in patients with upper gastrointestinal (GI) bleeds. MethodsThis retrospective study used the HCA Healthcare Enterprise Data Warehouse (EDW) to analyze 13,440 patients aged >18 years that were admitted with an upper GI bleed from January 2017 to December 2019. The patients were categorized based on oral anticoagulant (i.e. rivaroxaban, apixaban, dabigatran and warfarin). The control group was patients admitted with an upper GI bleed not on oral anticoagulation. We evaluated the severity of upper GI bleeds while on oral anticoagulation based on the outcomes: mortality rate, length of stay, acute renal failure, shock, and need for packed red blood cell transfusions (pRBC). Comorbid conditions assessed were coronary artery disease (CAD), chronic obstructive pulmonary disease (COPD), heart failure (HF), atrial fibrillation (AF), venous thromboembolism (VTE), peripheral vascular disease (PVD), tobacco abuse, alcohol abuse, and chronic kidney disease (CKD). Home use of proton pump inhibitors (PPI), aspirin, and P2Y12 inhibitors were also evaluated. ResultsPatients on a DOAC without home PPI have a mortality odds ratio of 3.066 with a confidence interval (CI) greater than 95% (1.48-6.26, p<0.05) compared to patients on a DOAC and home PPI. Patients on warfarin and no home PPI have a mortality odds ratio of 5.55 (95% CI (1.02-30.35), p<0.05) compared to those on warfarin with home PPI use. In the no anticoagulation group, those not on PPI have an odds ratio of 3.28 (95% CI (2.54-4.24), p<0.05) of death compared to home PPI use. There was no statistical difference in mortality between each DOAC and warfarin. There was no difference in the presence of acute renal failure or shock when comparing each DOAC, warfarin, and no medication. For patients presenting with GI bleed, 0.8414 units of pRBC were transfused. Patients not on oral anticoagulation were found to have statistically significant decrease in pRBC transfusion if they did not report alcohol use, CKD, HF, AF, VTE, PVD. Patients on DOACs and alcohol use have an average pRBC transfusion count that is 0.922 units more than those without reported alcohol use (p=0.006). In the warfarin group, there was no statistical significance noted when comparing pRBC transfusions and also when comparing to baseline comorbidities.ConclusionThe retrospective study leads us to conclude that overall, patients taking the DOACs or warfarin had no statistically significant increase in RBC transfusions, length of stay, shock, acute renal failure, or mortality rate compared to patients who were not on oral anticoagulation. Home PPI use was shown to lower odds of mortality in patients on anticoagulation who presented with upper GI bleeding. PPI use had no effect on the need for transfusion or length of stay in patients on anticoagulation. These results can help predict which patients are likely to have higher mortality based on the use of home PPIs.