Diagnosis Of Acute Chest Syndrome Research Articles

Length of Stay Is Associated with a Delay in Diagnosis of Acute Chest Syndrome in Sickle Cell Disease Patients: Leveraging Artificial Intelligence As a Tool for Earlier Diagnosis

Length of Stay Is Associated with a Delay in Diagnosis of Acute Chest Syndrome in Sickle Cell Disease Patients: Leveraging Artificial Intelligence As a Tool for Earlier Diagnosis

Prevalence and Time Trends of Oral Anticoagulant Utilization in Adults with Sickle Cell Disease

Background: Sickle cell disease (SCD) is an inherited red blood cell disorder, caused by a genetic mutation in the β-hemoglobin chain. SCD is associated with chronic activation of coagulation and an increased risk of venous thromboembolism (VTE). Although the American Society of Hematology guidelines recommend indefinite anticoagulation for unprovoked or recurrent provoked VTE, no guidance is given regarding choice of anticoagulant due to a paucity of data. Existing evidence on the use of anticoagulants in patients with SCD has been mostly focused on oral anticoagulants, was limited by small sample sizes, and did not clearly demonstrate the temporal utilization patterns. Real-world evidence on oral anticoagulant use in SCD from large population-based studies is largely lacking. This study examined the prevalence and time trends of oral anticoagulant utilization in patients with SCD in the United States (US). Methods: This retrospective, repeated cross-sectional study analyzed the Cerner Health Facts® database from January 1, 2011, to December 31, 2016, which captures longitudinal electronic medical records (EMR) of patient data from participating facilities in the US. To be included, patients were required to (1) have ≥ 1 inpatient or emergency department encounters with SCD, or 2 outpatient encounters that were 30 days apart in a calendar year from 2012 to 2016, (2) have ≥ 1 prescription records on the encounters with SCD, (3) aged ≥ 18 years at index, and (4) have ≥ 1 encounter with SCD in a year prior to the index. For patients with multiple encounters with SCD in the calendar year, we randomly selected one encounter with SCD and defined it as the index. In this design, a patient contributed only one observation per year but may contribute to multiple years of observations if meeting the selection criterion. The outcome was the use of anticoagulants, defined as any prescription drug encounter for an oral anticoagulant (Vitamin K antagonist [VKA]: warfarin; direct oral anticoagulants [DOACs]: apixaban, rivaroxaban, dabigatran, edoxaban) within a grace period of 7 days discharged from the index. The independent variable was each calendar year measured as dummy variables. Covariates were measured during the 12-month baseline period prior to the index, which included patient demographics, comorbidities and complications of SCD, and facility characteristics. Time trends on the proportions of eligible patients with anticoagulant use against the calendar years of the SCD diagnosis were plotted, and the significance on the crude trend was examined using Cochran-Armitage trend test. In the main analysis, a modified Poisson regression by using generalized estimating equations (GEEs) estimated the adjusted prevalence ratios (APRs) for the trends and covariates associated with any anticoagulant utilization. In subgroup analysis, we estimated the APRs of covariates for the use of DOACs versus VKA. Results: The cohort included 8,824 adult patients with SCD in 182 facilities using automated Cerner EMR system for the years 2012 to 2016. Prescription rates of all oral anticoagulants gradually increased from 2012 to 2014; the rates of VKA prescriptions substantially dropped from 11.1/1000 to 4.1/1000 persons between 2014 and 2016, whereas prescription rates of DOACs increased significantly from 12.0/1000 to 29.1/1000. Prevalence of VTE was stable at approximately 6.2/1000 to 7.5/1000 between 2012 and 2016. Prescription rates of DOACs were lower in patients with (versus without) VTE (6.1/1000 vs 7.3/1000), while a reversed prescription pattern was observed for VKA (VTE [yes vs no]: 4.4/1000 vs 1.8/1000). Controlling for covariates, our main analysis demonstrated that patients with a diagnosis of acute chest syndrome, pulmonary hypertension, and depression were 1.51, 2.30, and 1.57 times more likely to have oral anticoagulant prescription, respectively (all p <0.05). Subgroup analysis showed that having a diagnosis of VTE was associated with a decreased likelihood of DOACs prescription relative to VKA (APR= 0.75, 95%CI: 0.62-0.91). Conclusion: Prescription of oral anticoagulants in adults with SCD has significantly increased from 2012 to 2016 and the increase was dominated by DOACs. The treatment paradox of a lower relative rate of DOACs utilization versus VKA in adults with SCD requires more study to understand the reasons and additional clinical outcomes associated with the utilization patterns.

In Phase 2 and Phase 3 Trials, Broadening the Definition of Acute Vaso-Occlusive Pain to Include at Least One Episode of Pain Requiring Nsaids, Opioids, or Both Treatments at Home within 30 Days of a Physician Visit

Introduction:Despite the high incidence of acute painful events in children and adults with SCD, there is a lack of consensus on the acute pain definition in controlled clinical trials. To address this limitation, we elected to have three definitions of acute vaso-occlusive pain based on the setting for the pain location: inpatient, outpatient, ED, or at home. Based on the results of the SPRING Trial, the primary stroke prevention trial in children with SCD conducted in Nigeria (The Lancet Haematol. 2022 Jan 1;9(1):e26-37), and the PISCES study (Annals of internal medicine. 2008 Jan 15;148(2):94-101), most acute pain events in low-middle and high-income countries occur at home. We tested the hypothesis that the majority of negative phase 2 and phase 3-controlled trials for SCD failed to consider acute pain events in all four settings. Methods: To identify the relevant Phase II and III trials with acute pain as an outcome, we conducted a literature review using the website clinicaltrials.gov with the following key terms: “Sickle Cell Disease,” and “Vaso-occlusive.”. Studies that were not Phase II or Phase III were excluded from our search. We identified Phase 2 or 3 SCD pain trials published between 2015 and 2023. Inclusion criteria: definitions in the clinicaltrials.gov trial page, protocol, or method section. An inclusive, consensus definition for vaso-occlusive pain was chosen from the SPRING Trial. This definition was compared to the acute vaso-occlusive pain definitions of both SCD Phase 2 and 3 trials, with vaso-occlusive pain as a primary or secondary outcome. Based on the SPRING Trial and the results of the PISCES study, we elected to have three definitions of acute vaso-occlusive pain: 1. inpatient uncomplicated pain that excludes a concomitant diagnosis of acute chest syndrome; 2. Pain that required either an inpatient or outpatient visit and opioid treatment; and 3. An acute pain event at home requiring NSAIDs, opioids, or both. Only uncomplicated pain events were included to avoid double counting participants who developed acute chest syndrome or strokes that may have preceded the vaso-occlusive pain event. Results: We identified 35 articles based on our criteria. Our study sample included 3 clinical trials that led to the FDA approval for therapy to prevent acute vaso-occlusive pain events (FDA-approved therapy trials). Among these 35 trials, 32 clinical trials did not provide any evidence of the therapeutic benefits of the experimental agent (negative controlled trials). The three randomized controlled trials that led to FDA approval for therapy to prevent acute pain were: Hydroxyurea, L-Glutamine, and Crizanlizumab. Hospitalization for pain was included in all three FDA-approved therapy trials and 34.4% (11/32) of negative controlled trials. The ED visits in the pain definition were included in all 3 FDA-approved therapy trials and 28.1% (9/32) of negative controlled trials. Outpatient visits in the pain definition were included in all 3 FDA-approved therapy trials and 21.9% (7/32) of negative controlled trials. Home pain episodes were included in none of the FDA-approved therapy trials and 9.4% (3/32) of negative controlled trials. Finally, 43.8% (14/32) negative controlled trials were excluded as they failed to define vaso-occlusive pain in their methods or definition section and 15.6% (5/32) negative controlled trials did not have a publication. Conclusion: Most controlled trials designed to evaluate the efficacy of new treatment did not include the setting where pain occurs most frequently, at home. For future therapeutic trials designed to address whether a new therapy decreases the incidence rate of acute pain, we recommend an assessment of pain in all 4 four settings (Hospitalization, ED, Outpatient, and Home).

Pulmonary Embolism in Sickle Cell Disease: Retrospective Analysis of the Use and Yield of Radiographic Studies

▪Venous thromboembolism is a well-known complication of sickle cell disease1-3 and is associated with significant morbidity and mortality, particularly in the case of pulmonary embolisms. On the other hand, concerns have been raised regarding the overuse of imaging when evaluating for PE.4,5 Multiple algorithms have been developed, including the Geneva score,6 Wells' criteria,7 and Pulmonary Embolism Rule-Out Criteria (PERC),8 to better determine the pre-test probability of pulmonary embolism and help curtail the utilization of imaging. Patients with sickle cell disease, particularly when in vaso-occlusive crisis, may have a presentation that confounds the data incorporated into the algorithms, such as abnormal vital signs or d-dimer measurements, making the evaluation challenging. Furthermore, acute chest syndrome (ACS) is another notable acute clinical manifestation of sickle cell disease and can have symptoms and objective measures that are similar to PE with PE itself being a potential trigger for ACS. There is limited data on the extent to which SCD patients undergo scans to evaluate for PE and on the yield of these scans. While complications of SCD including ACS have been found to be more common in patients with hemoglobin SS than SC or sickle beta thalassemia,9 venous thromboembolism has been found to be more prevalent in SC and sickle beta thalassemia.2The sickle cell center at Grady Memorial Hospital, Atlanta, GA currently has more than 1,100 adult patients enrolled, accounting for the largest adult sickle cell population in North America. Through a retrospective chart review of these patients, we determined the prevalence of use of imaging to evaluate for pulmonary embolism and the yield from these radiographic studies, comparing this data across the hemoglobin genotypes. We also assessed for how often these these patients were ultimately diagnosed with ACS instead of or in addition to PE.In total, the charts of 1,143 patients were reviewed. 1,127 of these patients had clearly documented hemoglobin (Hgb) phenotypes; the 16 charts without known Hgb phenotype were excluded from further analysis. Of the 1,127 patients, 709 patients were Hgb SS, 311 SC, 87 sickle beta plus thalassemia (Sb+), 18 sickle beta zero thalassemia (Sb°), 1 SD, and 1 O-Arab. 231 (32.6%) of the Hgb SS patients had imaging while 69 (22.2%) of the SC patients (Table 1), 20 (23.0%) of the Sb+ patients, and 3 (16.7%) of the Sb° patients had imaging. SS patients had 21 (6.2%) studies positive for PE while SC patients had 17 (17.3%) (Table 1), Sb+ patients had 4 (13.3%), and Sb° patients had 2 (9.1%) such studies. Of the PEs diagnosed via CT scans, 13 out of the 17 positive studies for SS patients involved segmental vessels, which was the case with 11 out of 15 for SC patients. When imaged, either inpatient or outpatient, 81 (24.0%) of the cases involving SS patients resulted in a diagnosis of acute chest syndrome; this occurred in 15 (15.3%) of SC patient cases, 4 (13.3%) of Sb+ cases, and 1 (4.5%) of Sb° cases.In this study, we demonstrate that a significantly higher proportion of the Hgb SS patients underwent radiographic studies to evaluate for a pulmonary embolism compared to their SC counterparts despite having a significantly lower yield on these studies. However, the SS patients were more likely to be diagnosed with ACS, suggesting that this diagnosis may need to be more seriously considered before PE in this cohort. This data also suggests that though literature may have previously suggested that thromboembolic disease is more prevalent in SC than SS patients, there may be less awareness of such data among providers, who may be assuming that all sickle cell complications are most common in SS patients. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Radiological Patterns in Sickle Cell Disease Patients with Acute Chest Syndrome: Are There Age-Related Differences?

Background:Acute chest syndrome is a major cause of pulmonary disease and mortality in sickle cell disease patients. Its diagnosis can be delayed due to differing imaging patterns between children and adults.Objective:The purpose of this study was to describe the pulmonary and extrapulmonary imaging findings in sickle cell disease patients with acute chest syndrome and determine differences in findings between adult and pediatric patients.Patients and Methods:This retrospective study analyzed the data of all sickle cell disease patients who were admitted with a diagnosis of acute chest syndrome to King Fahd Hospital of the University, Al Khobar, Saudi Arabia, between January and June 2015 (n = 150). After grouping the patients into adults and pediatrics, the pulmonary and extrapulmonary characteristics were identified and the digital radiography, computed tomography and laboratory findings were compared.Results:A total of 116 patients with 163 acute chest syndrome episodes met the inclusion criteria, of which 69 (60%) were adults. In both adult and pediatric patients, the most frequent pulmonary finding was consolidation of the lung parenchyma. The right lung was most frequently involved: the lower lobe in adult patients and the middle lobe in pediatric patients. In addition, pleural effusion was observed in both age groups. Extrapulmonary radiological findings, such as avascular necrosis and cardiomegaly, were significantly more common in adult patients than in pediatric patients (P < 0.05). Compared with adults, pediatric patients had significantly lower hemoglobin levels (P = 0.001) and oxygen tension fraction in arterial blood (P = 0.007).Conclusions:Pediatric and adult sickle cell disease patients with acute chest syndrome typically exhibited similar pulmonary characteristics, whereas extrapulmonary findings were more prominent in adult patients. Furthermore, low levels of hemoglobin and oxygen tension fraction were dependent predictors of acute chest syndrome.

Unexplained Hypoxia and Shunting on Echocardiography in Patients with Sickle Cell Disease: A Retrospective Review

▪Introduction: During an episode of vaso-occlusive crisis, some patients with sickle cell disease may develop a transient hypoxemia. While frequently attributed to acute chest syndrome or pulmonary embolism, clinically a portion of patients develop hypoxemia without a clear etiology. On echocardiography, some patients were noted to have Patent Foramen Ovale (PFO) and others were noted to have intrapulmonary shunting. We sought to further characterize this clinical finding in sickle cell patients.Methods: We conducted a single institution retrospective chart review from 2008 through 2015 to evaluate the incidence of pulmonary shunting and PFOs in patients with SCD, as demonstrated on an echocardiography. We further characterize each of these episodes with clinical and laboratory findings at the time of the event. The presence of absence of shunting and type of shunting was further verified by a single cardiologist reviewing all episodes. Kruskal-Wallis test or Fisher's exact test was used to compare characteristics between patients with intracardiac or intrapulmonary shunting.Results: A total of 36 (18 female (F), 18 male (M)) of the 352 (10%) patients seen at the Ohio State Comprehensive Sickle Cell Center were noted to have shunting on their echocardiogram reported over the 7 year time period. Independent review by cardiology confirmed the presence of a shunt in 32 patients (9%, 95% CI: 6-13%) (15F, 17M). The median age at the time of reporting was 29 (range: 18-51 yrs). Shunting was observed in patients of all genotypes (94% SS/SB0; 6% SC/SBeta+). Fourteen (6 F, 8 M) of the thirty-two (44%, 95% CI: 26-62%) patients under study were noted to have cardiac shunting and eighteen (9 F, 9 M) (56%, 95% CI: 38-74%) were noted to have pulmonary shunting. In the patients with cardiac shunting, all 14/14 were confirmed to have a PFO by independent cardiac review. At the time of echo, 27/32 (87%) were hospitalized and 19/32 (59%) had clinical hypoxia on the day of the echocardiography. Patients with cardiac shunting tended to have higher proportion of hypoxia compared with patients with pulmonary shunting (71% vs. 50%). 19/32 (59%) had concurrent CT angiography and 1/32 (5%) patients was confirmed to have a pulmonary embolism. This patient demonstrated a concurrent PFO. 9 (28%) had a concurrent diagnosis of acute chest syndrome (4 with cardiac shunting and 5 with pulmonary shunting). The median value of TR jet velocity at baseline was 2.64 (range: 2.0-4.0) (n=18) and the median TR jet velocity at the time of event was 2.67 m/s (range: 2.0-3.8 m/s) (n=27). In the cardiac shunting group, the TR jet velocity was 2.85 m/s (range: 2.0 -3.27m/s) and in the pulmonary shunting group, the TR jet velocity was 2.6 m/s (range: 2.2-3.8 m/s).Conclusion: Patients with SCD presenting with increasing hypoxia may have intracardiac or intrapulmonary shunting. A patent foramen ovale that opens during vaso-ossclusive crisis may cause transient hypoxemia. This opening is thought to be due to increasing pulmonary pressures. While the long term implications of this finding are currently being studied, intracardiac shunting should be considered in the differential of patients with SCD presenting with increasing hypoxia of unclear etiology. DisclosuresNo relevant conflicts of interest to declare.

Accuracy of Point-of-care Lung Ultrasonography for Diagnosis of Acute Chest Syndrome in Pediatric Patients with Sickle Cell Disease and Fever.

The objective was to determine the test performance characteristics for point-of-care lung ultrasonography (LUS) performed by pediatric emergency medicine (PEM) physicians compared with radiographic diagnosis of acute chest syndrome (ACS) in patients with sickle cell disease (SCD) and fever. This was a prospective study of patients up to 21 years with SCD and fever requiring chest X-ray (CXR) evaluation for ACS. Before obtaining CXR, a blinded PEM physician performed LUS using a standardized scanning protocol. Positive LUS for ACS was defined as lung consolidation. All patients received CXR and follow-up. The criterion standard for ACS was consolidation on CXR as determined by a blinded radiologist. LUS clips were reviewed by a blinded expert PEM sonologist. A total of 116 febrile events from 91 patients with a median age of 5.7 years were enrolled by 15 PEM sonologists. CXR was positive for ACS in 15 (13%) patients, and LUS was positive for ACS in 19 (16%) patients. Positive LUS had a sensitivity of 87% (95% confidence interval [CI] = 62% to 96%), specificity of 94% (95% CI = 88% to 97%), positive likelihood ratio of 14.6 (95% CI = 6.5 to 32.5), and negative likelihood ratio of 0.14 (95% CI = 0.04 to 0.52) for ACS. The interobserver agreement (kappa) was 0.77. There were two missed cases of ACS on LUS. LUS may be sensitive and specific for diagnosis of ACS in pediatric patients with SCD and fever. LUS may reduce the need for routine CXR and associated ionizing radiation exposure in this population.

Síndrome torácico agudo en pacientes con anemia de células falciformes.

We report an unusual lethal complication of sickle cell anemia. The patient was admitted with a diagnosis of acute chest syndrome and died shortly thereafter of respiratory failure. Autopsy revealed numerous deposits of bone marrow hematopoietic tissue occluding the microvascular circulation of the lung. Numerous causes of acute chest syndrome in sickle cell anemia have been identified, including pulmonary embolism from infartion of bone marrow. However, the release of bone marrow hematopoietic tissue leading to pulmonary vascular occlusion is not generally recognized pre-mortem by treating physicians.

Safety and Efficacy of Adjuvant Low-Dose Ketamine Therapy for Patients with Sickle Cell Disease

AbstractAbstract ▪3226▪This icon denotes a clinically relevant abstract Background/Objectives:Opioids are the mainstay of therapy for painful vasoocclusive crises (VOCs) in sickle cell disease (SCD). For some patients, opioid-induced hyperalgesia caused by activation of N-methyl-D-aspartate (NMDA) receptors has been considered to contribute to poor analgesia. Ketamine, an NMDA receptor antagonist, could be a useful adjunct therapy; however safety concerns remain with its use. We examined records of SCD patients at our institution who received ketamine as an adjuvant to opioids at the discretion of anesthesia pain services over the past 4 years. We sought to explore the safety of ketamine and determine its effect on daily opioid requirement in SCD patients hospitalized for VOCs. Methods:The Institutional Review Board at Children's National Medical Center approved this study. A retrospective case-crossover study was conducted through review of the electronic medical record. For each patient we selected 2-paired hospitalizations occurring within 2 years of each other. One hospitalization where the patient received low-dose ketamine infusion in addition to opioid patient controlled analgesia (PCA), and a second hospitalization where the same patient received opioid PCA alone. We compared clinical characteristics of hospitalizations where patients did or did not receive ketamine. Exploratory bivariate analysis (paired t-test and McNemar's test) was used to compare variables between the pairs. Results:Thirty-three patients were identified to have at least 2 hospitalizations for VOC within 20 months of each other where they received adjuvant ketamine infusion during one, while not during the other. Average age was 15.6 ± 3.4 years, 67 % were females, and 36 % were on hydroxyurea therapy. SCD genotypes included homozygous SS 70%, SC 24 %, S-beta-zero thalassemia 3%, and S-beta-plus thalassemia 3%. Mean number of admissions in the 6 months prior to the ketamine hospitalization was 2 (range 0–5) and 64 % had ≥ 2 prior admissions within 6 months. Ketamine dose was 0.1 mg/kg/h for all patients except one who briefly received 0.15 mg/kg/hr. During the ketamine and opioid PCA hospitalization patients reported overall higher pain scores (6.53 vs. 5.94 out of 10; p = 0.0356), required higher doses of opioid (0.0395 mg/kg/hr vs. 0.0323 mg/kg/hr; p = 0.0038), and had a longer length of stay (LOS) (5.6 vs. 4.4 days; p =0.0148) as compared to the PCA alone hospitalization. Patients were more likely to have a diagnosis of acute chest syndrome (ACS) at some point during the ketamine and opioid PCA hospitalization (42% vs. 15 %; p = 0.0126) as compared to the opioid PCA alone hospitalization. Patients were more likely to be treated with additional adjuvant pain control agents (diazepam, lorazepam, gabapentin, pregabalin, amitripyline, or duloxetine) during the ketamine and opioid PCA admission as compared with opioid PCA alone admissions (45% vs. 9% p = 0.0013). Rates of red blood cell transfusion and ICU transfer were not different between the hospitalizations. In 3 patients ketamine was discontinued due to vivid dreams delusions, or dizziness. Nausea, pruritis, sedation, and use of complementary therapies were similar between hospitalizations. Conclusions:We did not observe an opioid sparing effect of ketamine infusion as hypothesized in this group of frequently hospitalized patients. Low-dose ketamine is a safe adjuvant medication for SCD patients hospitalized for VOCs. Higher opioid use during ketamine and opioid PCA admissions is likely due to patients experiencing more severe VOCs as indicated by higher pain scores involving multiple sites, higher rates of ACS, and longer LOS. These severity measures may have contributed to the decision of the pain medicine service to add low-dose ketamine infusion to standard opioid PCA in this retrospective sample. Finally, VOCs in this group of frequently admitted individuals may represent chronic pain which is known to be minimally responsive to most pharmacologic therapies. Patients receiving ketamine appear to be using additional adjuvant pain agents and may be underutilizing hydroxyurea. Prospective randomized studies of adjuvant ketamine therapy in patients with SCD are warranted to determine true efficacy. Disclosures:Off Label Use: Ketamine is a non-barbiturate phencyclidine derivative that is approved for use as a surgical anesthetic. It is not approved for use in pain management, however is commonly used in low-doses as an adjunct to traditional pain control therapies.

Clinical Predictors of All-Cause In-Hospital Mortality In Patients with Sickle Cell Disease in the United States- First Reported Results From A Nationally Representative Sample

Abstract 339Clinical Predictors Of All-Cause In-Hospital Mortality In Patients With Sickle Cell Disease in United States- First Reported Results From A Nationally Representative Sample. Background:Sickle cell disease is the most common monogenic abnormality affecting 70,000–100,000 people in the US, with a reported in-hospital mortality rate of 0.3–0.7%. Predictors of mortality in SCD however remain largely undefined and under-explored. In 2000, data from the Cooperative Study of Sickle Cell Disease had proposed dactylitis, severe anemia and leukocytosis as predictors of adverse events, including death in SCD (Miller et al, NEJM, 2000 13;342(2):83–9). Recently, various demographic predictors of in-hospital mortality including hospital volume, hospital teaching status, and patient socioeconomic status were proposed (McCavit et al Amer Jour Hematology, 2011, 86(4):377–80). However, till date no study has explored the clinical predictors of in-hospital mortality in patients with SCD. Aim:This study aims to explore the various clinical predictors of all cause mortality in hospitalized SCD patients using a nationally representative database. Methods:We used the Nationwide Inpatient Sample (NIS) database for the study. NIS is a stratified probability sample of 20% of all hospital discharges among U.S. community hospitals (n=1,044, sampling universe = 90% of all such discharges) sponsored by the Agency for Health Care Quality and Research.Presence of following ICD-9-CM diagnosis codes were used to define SCD related hospitalizations: 282.41, 282.42, 282.5, 282.60, 282.61, 282.62, 282.63, 282.64, 282.68, and 282.69. ICD-9-CM 99.04, 99.01 were used to identify packed red cell transfusion and exchange transfusion respectively. ICD-9-CM code 517.3 was used to identify ACS and 995.91, 995.92, and 038 were used to identify sepsis as a diagnosis during hospitalization for SCD. Only data on SCD related hospitalizations and mortality were analyzed.Sampling weights were applied to represent all community hospital discharges in the US for the year 2007. Univariate and multivariable logistic regression was performed for statistical analysis. A 2-sided p-value of <0.05 was considered significant. Results:In 2007, there were a total of 166,084 admissions with a diagnosis of SCD. Of these, 86,318 discharges had SCD as the primary diagnosis upon admission and 79,766 had SCD as one of the secondary diagnoses during the admission. Of these, males represented 37.5% of SCD related hospitalizations. There were a total of 844 deaths reported in the above admissions with an all-cause in-hospital mortality rate of 0.5%. Of these, 420(49.7%) were females.In the multivariable logistic regression model, the following clinical factors were independently associated with statistically significantly higher odds of mortality: Male gender, every ten year increase in age, history of at least one PRBC transfusion, history of exchange transfusion, diagnosis of acute chest syndrome and development of sepsis during the admissions (Table 1). On univariate analysis, history of mechanical ventilation (either non-invasive or invasive) was also a highly significant independent predictor of mortality [estimated OR (95% CI) = 120.9 (82.7–176.9)]. However, we did not include this in the final model as it can be an intermediary for other factors in the pathway leading to mortality and thus potentially introduce confounding in our analysis.Table 1:Clinical predictors of in-hospital mortality in patients with Sickle Cell Disease: Results From The National Inpatient SamplePredictorsOdds Ratio Estimates95% Wald Confidence Limitsp-valueFemale gender versus male1.61.12.2<0.01Every ten year increase in age1.61.41.7<.0001Simple Transfusion (yes versus no)1.71.22.4<0.01Exchange Transfusion (yes versus no)4.01.312.3<0.05Acute Chest Syndrome (yes versus no)2.61.54.5<0.01Sepsis (yes versus no)11.27.516.8<.0001All the above predictor variables were simultaneously included in the multivariable logistic regression model Conclusion:This study proposes for the first time, a set of clinical factors which are independent predictors of all –cause mortality in hospitalized patients with SCD. We propose that early and targeted aggressive therapy based on the presence of these factors should guide the management of hospitalized SCD patients for improved mortality. Disclosures:Krishnamurti:Daiichi Sankyo Company, Ltd. and Eli Lilly and Company: Research Funding.

Potential role of the ventilation and perfusion (V/Q) lung scan in the diagnosis of acute chest syndrome in adults with sickle cell disease

The current criteria for diagnosing ACS are chest pain and presence of a new infiltrate on the chest radiograph (CXR). This study was designed to evaluate the role of ventilation and perfusion (V/Q) scan to assist in the early diagnosis of ACS. An abnormal V/Q scan was associated with a diagnosis of ACS that reached a statistical significance (P < 0.038). The sensitivity and specificity were found to be 60% and 100%, respectively. We conclude that V/Q scan may play a role in the early diagnosis of ACS.