Padua Risk Assessment Model Research Articles

Caprini versus Padua venous thromboembolism risk assessment scores: A comparative study in hospitalized patients at a tertiary center.

To assess and compare the Caprini and Padua risk assessment models (RAMs) for predicting venous thromboembolism (VTE) in hospitalized patients. We retrospectively reviewed 28 VTE and 450 non-VTE patients hospitalized at King Abdulaziz University Hospital, Jeddah, Saudi Arabia, in 2019. Their baseline medical, demographic, and radiological reports were recorded. We compared Caprini scores (defined at admission) and Padua scores (calculated retrospectively) for their ability to predict VTE. A cumulative risk score was created by adding the individual scores for each risk factor. We also analyzed the sensitivity, specificity, and diagnostic accuracy of the RAM scores. Major differences in risk factors were shown between patients with and without VTE. Previous VTE was significantly associated with a higher risk of VTE (28.6%), as was reduced mobility (57.1%), acute infection (25%), high Caprini score (50%), and high Padua score (64.3%, p<0.05). The sensitivity of the Caprini score (96%) was higher than that of the Padua score (64.3%), as was the specificity (92.1% vs. 46.9%), positive predictive value (93% vs. 7%), and accuracy (94.1% vs. 47.9%). The specificity of the Caprini score was higher than that of the Padua score in Critical Care, Gynecology/Obstetrics, and Surgical departments. The Caprini RAM showed the lowest level of specificity in the medical department. The Caprini RAM demonstrated higher sensitivity, specificity, and predictive accuracy than did the Padua RAM and thus distinguished low and high VTE risk in hospitalized patients.

Effectiveness and cost effectiveness of pharmacological thromboprophylaxis for medical inpatients: decision analysis modelling study

ObjectiveTo determine the balance of costs, risks, and benefits for different thromboprophylaxis strategies for medical patients during hospital admission.DesignDecision analysis modelling study.SettingNHS hospitals in England.PopulationEligible adult medical inpatients, excluding patients...

External Validation of the ICU-Venous Thromboembolism Risk Assessment Model in Adult Critically Ill Patients.

Currently, no universally accepted standardized VTE risk assessment model (RAM) is specifically designed for critically ill patients. Although the ICU-venous thromboembolism (ICU-VTE) RAM was initially developed in 2020, it lacks prospective external validation. To evaluate the predictive performance of the ICU-VTE RAM in terms of VTE occurrence in mixed medical-surgical ICU patients. We prospectively enrolled adult patients in the ICU. The ICU-VTE score and Caprini or Padua score were calculated at admission, and the incidence of in-hospital VTE was investigated. The performance of the ICU-VTE RAM was evaluated and compared with that of Caprini or Padua RAM using the receiver operating curve. We included 269 patients (median age: 70 years; 62.5% male). Eighty-three (30.9%) patients experienced inpatient VTE. The AUC of the ICU-VTE RAM was 0.743 (95% CI, 0.682-0.804, P < 0.001) for mixed medical-surgical ICU patients. Comparatively, the performance of the ICU-VTE RAM was superior to that of the Pauda RAM (AUC: 0.727 vs 0.583, P < 0.001) in critically ill medical patients and the Caprini RAM (AUC: 0.774 vs 0.617, P = 0.128) in critically ill surgical patients, although the latter comparison was not statistically significant. The ICU-VTE RAM may be a practical and valuable tool for identifying and stratifying VTE risk in mixed medical-surgical critically ill patients, aiding in managing and preventing VTE complications.

Ability of Caprini and Padua risk-assessment models to predict venous thromboembolism in a nationwide Veterans Affairs study

ObjectiveVenous thromboembolism (VTE) is a preventable complication of hospitalization. Risk-stratification is the cornerstone of prevention. The Caprini and Padua are two of the most commonly used risk-assessment models (RAMs) to quantify VTE risk. Both models perform well in select, high-risk cohorts. Although VTE RAMs were designed for use in all hospital admissions, they are mostly tested in select, high-risk cohorts. We aim to evaluate the two RAMs in a large, unselected cohort of patients. MethodsWe analyzed consecutive first hospital admissions of 1,252,460 unique surgical and non-surgical patients to 1298 Veterans Affairs facilities nationwide between January 2016 and December 2021. Caprini and Padua scores were generated using the Veterans Affairs’ national data repository. We determined the ability of the two RAMs to predict VTE within 90 days of admission. In secondary analyses, we evaluated prediction at 30 and 60 days, in surgical vs non-surgical patients, after excluding patients with upper extremity deep vein thrombosis, in patients hospitalized ≥72 hours, after including all-cause mortality in a composite outcome, and after accounting for prophylaxis in the predictive model. We used area under the receiver operating characteristic curves (AUCs) as the metric of prediction. ResultsA total of 330,388 (26.4%) surgical and 922,072 (73.6%) non-surgical consecutively hospitalized patients (total N = 1,252,460) were analyzed. Caprini scores ranged from 0 to 28 (median, 4; interquartile range [IQR], 3-6); Padua scores ranged from 0-13 (median, 1; IQR, 1-3). The RAMs showed good calibration and higher scores were associated with higher VTE rates. VTE developed in 35,557 patients (2.8%) within 90 days of admission. The ability of both models to predict 90-day VTE was low (AUCs: Caprini, 0.56; 95% confidence interval [CI], 0.56-0.56; Padua, 0.59; 95% CI, 0.58-0.59). Prediction remained low for surgical (Caprini, 0.54; 95% CI, 0.53-0.54; Padua, 0.56; 95% CI, 0.56-0.57) and non-surgical patients (Caprini, 0.59; 95% CI, 0.58-0.59; Padua, 0.59; 95% CI, 0.59-0.60). There was no clinically meaningful change in predictive performance in any of the sensitivity analyses. ConclusionsCaprini and Padua RAM scores have low ability to predict VTE events in a cohort of unselected consecutive hospitalizations. Improved VTE RAMs must be developed before they can be applied to a general hospital population.

Comparing the application of three thrombosis risk assessment models in patients with acute poisoning: A cross-sectional survey.

Patients with acute toxic hemoperfusion are prone to deep vein thrombosis. However, there is no risk assessment model for thrombosis in patients with acute toxic hemoperfusion. Therefore, we compared three commonly used risk assessment models for deep vein thrombosis to determine the model most suitable for assessment of deep vein thrombosis in patients with acute toxic hemoperfusion. Caprini, Autar, and Padua thrombosis risk assessment models were used to assess the risk of deep vein thrombosis in patients with acute poisoning and hemoperfusion admitted to a grade A hospital in Shandong province from October 2017 to February 2019. The predictive values of the three models were compared using receiver operating characteristic (ROC) curve analysis. The risk assessment model scores of Caprini, Autar, and Padua were 7.55 ± 1.76, 8.63 ± 2.36, and 3.92 ± 0.55, respectively. The Caprini risk assessment model was significantly different (p < 0.05) in high-risk patients in the thrombus and non-thrombotic groups; the difference between the other two models was not significant (p > 0.05). The areas under the ROC curve of the Caprini, Autar, and Padua risk assessment models were 0.673, 0.585, and 0.535, respectively. The difference in areas under the ROC curve between the Caprini risk assessment model and the Autar risk assessment model as well as the Padua risk assessment model was significant (p < 0.05), but the areas under the ROC curve of the Autar risk assessment model and the Padua risk assessment model were not statistically significant (p > 0.05). The Caprini risk assessment model had a sensitivity of 91.9%, specificity of 33.1%, and a Youden index of 0.249. The sensitivity and specificity of Autar's risk assessment model were 37.0 and 77.2%, respectively, and the Youden index was 0.141. The Padua risk assessment model had a sensitivity of 91.3%, specificity of 15.0%, and a Youden index of 0.063. The three thrombosis risk assessment models were not suitable for patients with acute poisoning and hemoperfusion.

Validation of Risk Assessment Models Predicting Venous Thromboembolism in Inpatients with Acute Exacerbation Of Chronic Obstructive Pulmonary Disease: A Multicenter Cohort Study in China

Inpatients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) are at increased risk for venous thromboembolism (VTE); however, the prophylaxis for VTE is largely underused in China. Identifying high-risk patients requiring thromboprophylaxis is critical to reduce the mortality and morbidity associated with VTE. This study aimed to evaluate and compare the validities of the Padua Prediction Score and Caprini risk assessment model (RAM) in predicting the risk of VTE in inpatients with AECOPD in China. The inpatients with AECOPD were prospectively enrolled from seven medical centers of China between September 2017 and January 2020. Caprini and Padua scores were calculated on admission, and the incidence of 3-month VTE was investigated. Among the 3,277 eligible patients with AECOPD, 128 patients (3.9%) developed VTE within 3 months after admission. The distribution of the study population by the Caprini risk level was as follows: high, 53.6%; moderate, 43.0%; and low, 3.5%. The incidence of VTE increased by risk level as high, 6.1%; moderate, 1.5%; and low, 0%. According to the Padua RAM, only 10.9% of the study population was classified as high risk and 89.1% as low risk, with the corresponding incidence of VTE of 7.9 and 3.4%, respectively. The Caprini RAM had higher area under curve compared with the Padua RAM (0.713 ± 0.021 vs. 0.644 ± 0.023, p = 0.029). The Caprini RAM was superior to the Padua RAM in predicting the risk of VTE in inpatients with AECOPD and might better guide thromboprophylaxis in these patients.

Venous thromboembolism risk factors and prophylaxis of elderly intensive care unit patients in a Chinese general hospital.

To analyze the venous thromboembolism (VTE) risk factors and prophylaxis of elderly patients in the intensive care unit (ICU). We retrospectively recruited 200 elderly patients with VTE and 234 non-VTE patients. VTE risk factors were got from data of all patients. The sensitivity and specificity of the Caprini scores and Padua scores were calculated. We use the receiver operating characteristic (ROC) curve and the area under the curve (AUC) to evaluate each score. We found that male sex, sepsis, being bedridden (>72 hours), pneumonia, history of deep vein thrombosis (DVT), diabetes mellitus, coronary heart disease, heart failure, glucocorticoid treatment, PaO2, hemoglobin (Hb), prothrombin time (PT), and international normalized ratio (INR), D-dimer (D-D), mechanical ventilation, and continuous renal replacement therapy (CRRT) were significantly associated with VTE in elderly ICU patients (P<0.05). For elderly patients in the ICU, the predictive ability of Caprini risk assessment model was better than that of the Padua risk assessment model. Among the high VTE risk elderly patients, the number of patients receiving mechanical prophylaxis in the high bleeding-risk group was higher than that in the low bleeding-risk group (P<0.0001). Elderly patients in the ICU have the highest risk of VTE and high bleeding risk; decisions concerning clinical prophylaxis should be made after appropriate information on the risk and benefit on an individual level is considered.

Caprini及Padua风险评估模型评估内科住院患者静脉血栓栓塞症风险有效性研究

Caprini及Padua风险评估模型评估内科住院患者静脉血栓栓塞症风险有效性研究

Venous Thromboembolism Prevention in COVID-19: A Review of Latest Evidences

COVID-19 has become major public health problems, with new cases and deaths growing around the world. COVID-19 has been reportedly associated with hypercoagulable state which can lead to venous thromboembolism (VTE) formation. This condition is also associated with worse outcomes in COVID-19 patients, therefore, it is critical for clinicians to identify this condition and manage it accordingly. VTE formation in COVID-19 occurs through several mechanisms, such as inflammatory reaction leading to hypercoagulable state and vascular dysfunction, direct vascular injury by the virus, and immobilization of the patients. The rate of VTE formation is as high as 31% in ICU patients and 9.2% in general wards patients, and it is also associated with poorer prognosis. Thromboprophylaxis with heparin, particularly low molecular weight heparin (LMWH), has been shown to improve the prognosis in these patients. A careful individual assessment is required to determine which patients will benefit from this therapy, as there are still no sufficient prospective trials to establish guidelines for VTE thromboprophylaxis in COVID-19. The assessment includes laboratory parameters such as PT, platelet count, D-dimer, fibrinogen, and other risk factors incorporated in PADUA risk assessment model (RAM), versus the risk of bleeding incorporated in IMPROVE bleeding RAM.

A Prospective Observational Cohort of Clinical Outcomes in Medical Inpatients prescribed Pharmacological Thromboprophylaxis Using Different Clinical Risk Assessment Models(COMPT RAMs)

The Caprini and Padua venous thromboembolism (VTE) risk assessment models (RAMs) are used to assess VTE risk in surgical and in medical patients respectively. This study aims to compare the proportion of medical inpatients eligible for VTE prophylaxis using the hospital Caprini-based RAM to using the Caprini and Padua RAMs and to assess the associated clinical outcomes. In a prospective observational study, we assessed 297 adult medical inpatients for whom VTE thromboprophylaxis was initiated according to the hospital Caprini-based RAM, referred to as the Lebanese American University Medical Center RAM (LAUMC-RAM). The Padua, Caprini and IMPROVE bleeding risk scores were also assessed for all patients. Bleeding and thromboembolism were evaluated at 14 and 30 days post VTE risk assessment. Pharmacologic thromboprophylaxis was warranted in 97.6%, 99.7%, and 52.9% of patients using the Caprini-based, Caprini, and Padua RAMs respectively. The Caprini-based and Caprini RAMs were highly correlated (r = 0.873 p < 0.001) and were significantly less correlated with the Padua RAM. Major and overall bleeding occurred in 1.4% and 9.2% respectively. VTE was reported in 0.4% with no VTE related mortality. In hospitalized medical patients, the Caprini-based RAM can accurately distinguish low and high VTE risk without resulting in increased risk of bleeding.

Performance of Risk Assessment Models for Peripartum Thromboprophylaxis

There is no consensus on which risk stratification approach to use for thromboprophylaxis in pregnancy, and most available risk assessment models (RAMs) for venous thromboembolism (VTE) events have not been validated in pregnancy. Our objective was to compare the performance of some of the most commonly used VTEs RAMs in our patient population in the peripartum period. This is a retrospective cohort of women who delivered at our institution in 2015 and 2016. We excluded patients with history of prior or current VTEs or those already receiving anticoagulants. Antepartum, intrapartum, and postpartum records were reviewed. Data were collected on known risk factors for VTEs in order to calculate scores for 3 RAMs on admission for delivery: Padua, Caprini, and Royal College of Obstetricians and Gynaecologists (RCOG). The primary objective was to the estimate the performance of the various RAMs in preventing postpartum VTEs. We calculated the proportion of women who would have been high risk, determined the number of VTEs cases within high- and low-risk categories, as well as calculated the number needed to treat (NNT) for each RAM. We performed analyses using different RAM scores cutoffs, VTEs outcome rates, and effectiveness of anticoagulation to prevent VTEs. The P value <.05 was considered statistically significant. A total of 6094 women were included. Three women had VTEs for an overall rate of 0.04% (N = 3; 95% confidence interval [CI]: 0.01-0.15). The proportion of women categorized as high risk for VTEs were 62% (95% CI: 61-64) for RCOG, 0.8% (95% CI: 0.6-1.0) for Padua, and 94% (95% CI: 94-95) for Caprini. Of the 3 VTEs, the RCOG model classified 1 woman as high risk and Padua model classified 3 women as high risk; whereas the Caprini did not identify any women as high risk. Assuming 100% effectiveness of thromboprophylaxis, the observed NNT was 3838 using RCOG, not able to calculate using Padua (no VTEs cases occurred in the high-risk group, thus none were prevented), and 1927 using Caprini. The rates of VTEs in pregnancy are very low and the available RAMs do not identify most of them. The RCOG and Caprini RAMs would categorize a large proportion of women as high risk and are associated with high NNTs. The Padua RAM appears to have the lowest NNT but missed all the VTEs in our cohort.

Use of thromboprophylaxis for venous thromboembolism among patients admitted in medical ward

Introductions: Studies have shown inadequate use of prophylaxis for venous thromboembolism (VTE) in hospital admitted medical patients. This study aims to evaluate the use of VTE prophylaxis in admitted medical patients in a tertiary care teaching hospital.&#x0D; Methods: This was a cross sectional observational study for three weeks from 19 March to 8 April 2017 in patients admitted in the medical ward of Patan Hospital, Patan Academy of Health Sciences, Lalitpur, Nepal. Patient charts were reviewed for appropriate VTE prophylaxis as per modified Padua risk Assessment model. Risks of VTE, presence of bleeding risks, demographics (age, BMI), hospital stay were descriptively analysed.&#x0D; Results: Out of 122 patients, 81 (66.4%) were at risk of VTE. Among 81 at risk, 69 were eligible for VTE pharmacoprophylaxis with no risk of bleeding only 29 (42%) received pharmacoprophylaxis and 12 eligible for prophylaxis but with the risk of bleeding did not receive any prophylaxis. Reduced mobility was the most common indication of thromboprophylaxis in 79 (64%), followed by acute infection 50 (41%).&#x0D; Conclusions: There was suboptimal use of thromboprophylaxis in hospital admitted medical patients at risk of venous thromboembolism, VTE.

Risk Assessment in Chinese Hospitalized Patients Comparing the Padua and Caprini Scoring Algorithms

The current venous thromboembolism (VTE) guidelines recommend all patients to be assessed for the risk of VTE using risk assessment models (RAMs). The study was to evaluate the performance of the Caprini and Padua RAMs among Chinese hospitalized patients. We reviewed data from 189 patients with deep venous thrombosis (DVT) and 201 non-DVT patients. Deep venous thrombosis risk factors were obtained from all patients. The sensitivity and specificity of the Caprini and Padua scores for all patients were calculated. The receiver operating curve (ROC) and the area under the ROC curve (AUC) were used to evaluate the performance of each score. We documented that age, acute infection, prothrombin time (PT), D-dimer, erythrocyte sedimentation rate, blood platelets, and anticoagulation were significantly associated with the occurrence of DVT (P < .05). These results were true for all medical and surgical patients group (G1), as well as the analysis of medical versus surgical patients (G2). Finally, analysis of the scores in patients with and without cancer was also done (G3). The Caprini has a higher sensitivity but a lower specificity than the Padua (P < .05). Caprini has a better predictive ability for the first 2 groups (P < .05). We found Caprini and Padua scores have a similar predictive value for patients with cancer (P > .05), while Caprini has a higher predictive ability for no cancer patients in G3 than Padua (P < .05). For Chinese hospitalized patients, Caprini has a higher sensitivity but a lower specificity than Padua. Overall, Caprini RAM has a better predictive ability than Padua RAM.

Appropriateness of Pharmacologic Prophylaxis against Deep Vein Thrombosis in Medical Wards of an Ethiopian Referral Hospital.

Background Most of hospitalized patents are at risk of developing deep vein thrombosis (DVT). The use of pharmacological prophylaxis significantly reduces the incidence of thromboembolic events in high risk patients. The aim of this study was to assess appropriateness of DVT prophylaxis in hospitalized medical patients in an Ethiopian referral hospital. Methods Cross-sectional study design was employed. Patients with a diagnosis of DVT, taking anticoagulant therapy, and those who refused to participate were excluded from the study. Two hundred and six patients were included in the study using simple random sampling method. Modified Padua Risk Assessment Model was used to determine the risk of thromboembolism. SPSS (version 21) was used for analysis. Result The total risk score for the study subjects ranged from 0 to 11 with a mean score of 3.41 ± 2.55. Nearly half (47.6%) of study participants had high risk to develop thromboembolism. Thrombocytopenia (platelets < 50 billion/L) or coagulopathy, active hemorrhage, and end stage liver disease (INR > 1.5) were the frequently observed absolute contraindications that potentially prevent patients from receiving thromboprophylaxis. Thromboprophylaxis use in nearly one-third (31.6%) of patients admitted in the medical ward of UoGRH was irrational. Patients who had high risk for thromboembolism are more likely to be inappropriately managed for their risk of thromboembolism and patients with thrombocytopenia or coagulopathy were more likely to be managed appropriately. Conclusion There is underutilization of pharmacologic thromboprophylaxis in medical ward patients. Physicians working there should be aware of risk factors for DVT and indications for pharmacologic thromboprophylaxis and should adhere to guideline recommendations.

Pharmaco-prophylaxis of deep vein thrombosis for in-patients at risk, in a tertiary care hospital

Background: There is limited data from India on Deep Vein Thrombosis (DVT) Prophylaxis. This study was done in hospitalised patients at high risk for DVT, to determine the patterns and rates of pharmacoprophylaxis, drugs used and their clinical outcomes.Methods: This prospective study screened patients for risk of DVT using the Padua risk assessment model. Padua score ≥4 were included and data on disease demographics, prophylaxis and outcomes of DVT at 12 weeks were collected. Factors affecting prophylaxis were assessed using multivariate logistic regression.Results: Out of 453 screened, 200 eligible patients were recruited. 48.5% were females; mean age was 54.6±16.6; 50.5% received some thromboprophylaxis, of which 24%, 35.5% and 9% received pharmacoprophylaxis, mechanoprophylaxis and a combination of both respectively. Low Molecular Weight Heparin was the most commonly used drug (77.1%). Adverse drug reactions reported were 24, none related to anticoagulant use. At 12 weeks, 18 (9%) patients gave history suggestive of DVT. 5 deaths were reported, but the cause could not be ascertained. Patients who had cardiac/ respiratory failure [OR =5.2 (95%CI - 1.13, 24.6), p = 0.03], acute MI or stroke [OR = 9.0 (3.5, 23.09), p &lt;0.001], those admitted to medical specialties [OR = 3.4 -1.4, 7.9), p = 0.004] and to private wards [OR = 7.4 (3.13, 17.5), p &lt;0.001] had significantly higher chances of receiving prophylaxis.Conclusions: Underutilisation of effective prophylaxis, despite high prevalence of DVT risk. Emphasis on routine risk assessment of hospitalized patients and administration of appropriate prophylaxis to those at high risk is required.

Prophylactic Dose Low Molecular Weight Heparin (dalteparin) For Treatment Of Vaso-Occlusive Pain Crisis In Patients With Sickle Cell Disease

The most common cause for hospitalization and the hallmark of sickle cell disease (SCD) is painful vaso-occlusive crisis (VOC). Several studies including our own have documented a hypercoagulable state in patients with SCD, which becomes further accentuated during pain crisis. Therefore, there has been increasing interest in the use of anticoagulation in patients with SCD to prevent and treat VOC. For patients admitted for VOC, deep vein thrombosis (DVT) prophylaxis with low molecular weight heparin (LWMH) is currently used at the discretion of the treating physician. No formal guidelines in the United States advocate universal use of DVT prophylaxis for patients with SCD and DVT risk assessment tools such as the Padua risk assessment model do not include SCD as a thrombophilic condition. We hypothesized that the daily use of prophylactic dose LMWH would decrease markers of hypercoagulability and daily pain scores for patients admitted for VOC.We performed a double blind placebo controlled trial using prophylactic dose dalteparin for patients with SCD admitted for VOC. Adult patients >18 years of age were enrolled at Duke University and included sickle cell type SS, SC, and Sβ0. Patients were treated for the initial 7 days of hospitalization, had pain scores (visual analog scale) recorded twice daily, and had hypercoagulable markers drawn on days 1, 3 and 5. Hypercoagulable markers tested included D-dimer, thombin-antithrombin (TAT), and calibrated automated thrombography (CAT). Analysis was performed to compare the amount of change in hypercoagulable markers and pain scores for each patient treated with either dalteparin or placebo.We enrolled 34 patients (median 27 years old, range 20-56) over 18 months, including 29 patients who were randomized and administered study drug. Ten patients treated with dalteparin and ten treated with placebo had blood drawn on day 1 and 3. Mean age, clinical history, and baseline laboratory values were not significantly different between dalteparin and placebo groups except for LDH, which was lower in the dalteparin group (303.9 U/L ± 120.9 vs. 432.6 ± 188, p=0.03). There was no significant difference between dalteparin and placebo treated patients for hypercoagulable markers on day 1 and 3 including: D-dimer (167.4 ng/mL ± 262.6 vs. 814 ± 621.8, p=0.19), TAT, and each phase of thrombin generation by CAT including endogenous thrombin potential (59.1 nM ± 26.8 vs. -24.3 ± 60.6, p=0.13). There also was no significant decrease between all hypercoagulable markers on day 1 when compared to day 5. Pain scores were found to significantly decrease each day during hospitalization from enrollment (day 0) to day 3 for each treatment group. Importantly, when comparing patients treated with dalteparin versus placebo, there was a greater decrease in pain scores from day 0 to 1 (-1.6 vs. -0.3, p=0.06) and from day 0 to 3 (-2.4 vs. -0.9, p=0.07).No studies to date have evaluated the use of prophylactic dose LMWH for the treatment of inpatient pain crisis. We found that prophylactic dose dalteparin did not seem to significantly affect hypercoagulable markers including D-dimer and CAT. Interestingly, there was also no significant decrease in markers through hospitalization from day 1 to day 5. This may be due to the underlying accentuated hypercoagulable state in SCD and the prophylactic dosing of dalteparin. We did find, however, a greater decrease in pain scores from day 0 to 1 as well as day 0 to 3 for patients treated with prophylactic dose dalteparin as compared to patients treated by placebo. This decrease in pain seems promising for larger multi-center studies to evaluate the use of prophylactic dose anticoagulation for VOC. Disclosures:Shah:Eisai: Research Funding. Telen:GlycoMimetics, Inc.: Research Funding; Dilaforette, NA: Research Funding; Pfizer, Inc.: Consultancy.