Post-discharge Venous Thromboembolism Risk Research Articles

The Duration and Magnitude of Postdischarge Venous Thromboembolism Following Colectomy.

Objective:To assess the impact of current guidelines by reporting weekly postoperative postdischarge venous thromboembolism (VTE) rates.Summary Background Data:Disparity exists between the postoperative thromboprophylaxis duration colectomy patients receive based on surgical indication, where malignant resections routinely receive 28 days extended thromboprophylaxis into the postdischarge period and benign resections do not.Methods:English national cohort study of colectomy patients between 2010 and 2019 using linked primary (Clinical Practice Research Datalink) and secondary (Hospital Episode Statistics) care data. Stratified by admission type and surgical indication, absolute incidence rates (IRs) per 1000 person-years and adjusted incidence rate ratios (aIRRs) for postdischarge VTE were calculated for the first 4 weeks following resection and postdischarge VTE IRs for each postoperative week to 12 weeks postoperative.Results:Of 104,744 patients, 663 (0.63%) developed postdischarge VTE within 12 weeks after colectomy. Postdischarge VTE IRs per 1000 person-years for the first 4 weeks postoperative were low following elective resections [benign: 20.66, 95% confidence interval (CI): 13.73–31.08; malignant: 28.95, 95% CI: 23.09–36.31] and higher following emergency resections (benign: 47.31, 95% CI: 34.43–65.02; malignant: 107.18, 95% CI: 78.62–146.12). Compared with elective malignant resections, there was no difference in postdischarge VTE risk within 4 weeks following elective benign colectomy (aIRR=0.92, 95% CI: 0.56–1.50). However, postdischarge VTE risks within 4 weeks following emergency resections were significantly greater for benign (aIRR=1.89, 95% CI: 1.22–2.94) and malignant (aIRR=3.13, 95% CI: 2.06–4.76) indications compared with elective malignant colectomy.Conclusions:Postdischarge VTE risk within 4 weeks of colectomy is ∼2-fold greater following emergency benign compared with elective malignant resections, suggesting emergency benign colectomy patients may benefit from extended VTE prophylaxis.

Association of Bleeding Severity With Mortality in Extended Thromboprophylaxis of Medically Ill Patients in the MAGELLAN and MARINER Trials.

Extended thromboprophylaxis has not been widely implemented in acutely ill medical patients because of bleeding concerns. The MAGELLAN (Multicenter, Randomized, Parallel Group Efficacy and Safety Study for the Prevention of Venous Thromboembolism in Hospitalized Medically Ill Patients Comparing Rivaroxaban With Enoxaparin) and MARINER (Medically Ill Patient Assessment of Rivaroxaban Versus Placebo in Reducing Post-Discharge Venous Thrombo-Embolism Risk) trials evaluated whether rivaroxaban compared with enoxaparin or placebo could prevent venous thromboembolism without increased bleeding. We hypothesized that patients with major bleeding but not those with nonmajor clinically relevant bleeding would be at an increased risk of all-cause mortality (ACM). We evaluated all bleeding events in patients taking at least 1 dose of study drug and their association with ACM in 4 mutually exclusive groups: (1) no bleeding, or first event was (2) nonmajor clinically relevant bleeding, (3) major bleeding, or (4) trivial bleeding. Using a Cox proportional hazards model adjusted for differences in baseline characteristics associated with ACM, we assessed the risk of ACM after such events. Compared with patients with no bleeding, the risk of ACM for patients with nonmajor clinically relevant bleeding was not increased in MARINER (hazard ratio, 0.43; P=0.235) but was increased in MAGELLAN (hazard ratio, 1.74; P=0.021). Major bleeding was associated with a higher incidence of ACM in both studies, whereas trivial bleeding was not associated with ACM in either study. Patients with major bleeding had an increased risk of ACM, whereas nonmajor clinically relevant bleeding was not consistently associated with an increased risk of death. These results inform the risk-benefit calculus of extended thromboprophylaxis in medically ill patients. URL: https://www. gov; Unique identifier: MAGELLAN, NCT00571649. URL: https://www. gov; Unique identifier: MARINER, NCT02111564.

Factors Associated With Risk of Postdischarge Thrombosis in Patients With COVID-19

COVID-19 is associated with a high incidence of thrombotic events; however, the need for extended thromboprophylaxis after hospitalization remains unclear. To quantify the rate of postdischarge arterial and venous thromboembolism in patients with COVID-19, identify the factors associated with the risk of postdischarge venous thromboembolism, and evaluate the association of postdischarge anticoagulation use with venous thromboembolism incidence. This is a cohort study of adult patients hospitalized with COVID-19 confirmed by a positive SARS-CoV-2 test. Eligible patients were enrolled at 5 hospitals of the Henry Ford Health System from March 1 to November 30, 2020. Data analysis was performed from April to June 2021. Anticoagulant therapy after discharge. New onset of symptomatic arterial and venous thromboembolic events within 90 days after discharge from the index admission for COVID-19 infection were identified using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes. In this cohort study of 2832 adult patients hospitalized with COVID-19, the mean (SD) age was 63.4 (16.7) years (IQR, 53-75 years), and 1347 patients (47.6%) were men. Thirty-six patients (1.3%) had postdischarge venous thromboembolic events (16 pulmonary embolism, 18 deep vein thrombosis, and 2 portal vein thrombosis). Fifteen (0.5%) postdischarge arterial thromboembolic events were observed (1 transient ischemic attack and 14 acute coronary syndrome). The risk of venous thromboembolism decreased with time (Mann-Kendall trend test, P < .001), with a median (IQR) time to event of 16 (7-43) days. There was no change in the risk of arterial thromboembolism with time (Mann-Kendall trend test, P = .37), with a median (IQR) time to event of 37 (10-63) days. Patients with a history of venous thromboembolism (odds ratio [OR], 3.24; 95% CI, 1.34-7.86), peak dimerized plasmin fragment D (D-dimer) level greater than 3 μg/mL (OR, 3.76; 95% CI, 1.86-7.57), and predischarge C-reactive protein level greater than 10 mg/dL (OR, 3.02; 95% CI, 1.45-6.29) were more likely to experience venous thromboembolism after discharge. Prescriptions for therapeutic anticoagulation at discharge were associated with reduced incidence of venous thromboembolism (OR, 0.18; 95% CI, 0.04-0.75; P = .02). Although extended thromboprophylaxis in unselected patients with COVID-19 is not supported, these findings suggest that postdischarge anticoagulation may be considered for high-risk patients who have a history of venous thromboembolism, peak D-dimer level greater than 3 μg/mL, and predischarge C-reactive protein level greater than 10 mg/dL, if their bleeding risk is low.

A postdischarge venous thromboembolism risk calculator for inflammatory bowel disease surgery

BackgroundGuidelines recommend extended chemoprophylaxis for venous thromboembolism in high-risk patients having operations for inflammatory bowel disease. Quantifying patients' risk of venous thromboembolism, however, remains challenging. We sought (1) to identify factors associated with postdischarge venous thromboembolism in patients undergoing colorectal resection for inflammatory bowel disease and (2) to develop a postdischarge venous thromboembolism risk calculator to guide prescribing of extended chemoprophylaxis. MethodsPatients who underwent an operation for inflammatory bowel disease from 2012 to 2018 were identified from the American College of Surgeons National Surgical Quality Improvement Program for colectomy and proctectomy procedure targeted modules. Postdischarge venous thromboembolism included pulmonary embolism or deep vein thrombosis diagnosed after discharge from the index hospitalization. Multivariable logistic regression estimated the association of patient/operative factors with postdischarge venous thromboembolism. A postdischarge venous thromboembolism risk calculator was subsequently constructed. ResultsOf 18,990 patients, 199 (1.1%) developed a postdischarge venous thromboembolism within the first 30 postoperative days. Preoperative factors associated with postdischarge venous thromboembolism included body mass index (1.9% with body mass index ≥35 vs 0.8% with body mass index 18.5–24.9; odds ratio 2.34 [95% confidence interval 1.49–3.67]), steroid use (1.3% vs 0.7%; odds ratio 1.91 [95% confidence interval 1.37–2.66]), and ulcerative colitis (1.5% vs 0.8% with Crohn’s disease; odds ratio 1.76 [95% confidence interval 1.32–2.34]). Minimally invasive surgery was associated with postdischarge venous thromboembolism (1.2% vs 0.9% with open; odds ratio 1.42 [95% confidence interval 1.05–1.92]), as was anastomotic leak (2.8% vs 1.0%; odds ratio 2.24 [95% confidence interval 1.31–3.83]) and ileus (2.1% vs 0.9%; odds ratio 2.60 [95% confidence interval 1.91–3.54]). The predicted probability of postdischarge venous thromboembolism ranged from 0.2% to 14.3% based on individual risk factors. ConclusionPreoperative, intraoperative, and postoperative factors are associated with postdischarge venous thromboembolism after an operation for inflammatory bowel disease. A postdischarge venous thromboembolism risk calculator was developed which can be used to tailor extended venous thromboembolism chemoprophylaxis by individual risk.

Development and validation of a risk calculator for post-discharge venous thromboembolism following hepatectomy for malignancy

BackgroundPost-discharge venous thromboembolism (VTE) chemoprophylaxis decreases VTEs following cancer surgery, however identifying high-risk patients remains difficult. Our objectives were to (1) identify factors available at hospital discharge associated with post-discharge VTE following hepatectomy for malignancy and (2) develop and validate a post-discharge VTE risk calculator to evaluate patient-specific risk. MethodsPatients who underwent hepatectomy for malignancy from 2014 to 2017 were identified from the ACS NSQIP hepatectomy procedure targeted module. Multivariable logistic regression identified factors associated with post-discharge VTE. A post-discharge VTE risk calculator was constructed, and predicted probabilities of post-discharge VTE were calculated. ResultsAmong 11 172 patients, 95 (0.9%) developed post-discharge VTE. Post-discharge VTE was associated with obese BMI (OR 2.29 vs. normal BMI [95%CI 1.31–3.99]), right hepatectomy/trisegmentectomy (OR 1.63 vs. partial/wedge [95%CI 1.04–2.57]), and several inpatient postoperative complications: renal insufficiency (OR 5.29 [95%CI 1.99–14.07]), transfusion (OR 1.77 [95%CI 1.12–2.80]), non-operative procedural intervention (OR 2.97 [95%CI 1.81–4.86]), and post-hepatectomy liver failure (OR 2.22 [95%CI 1.21–4.08]). Post-discharge VTE risk ranged from 0.3% to 30.2%. Twenty iterations of 10-fold cross validation identified internal validity. ConclusionsRisk factors from all phases of care, including inpatient complications, are associated with post-discharge VTE following hepatectomy. Identifying high-risk patients may allow for personalized risk-based post-discharge chemoprophylaxis prescribing.

Post-discharge venous thromboembolism after pancreatectomy for malignancy: Predicting risk based on preoperative, intraoperative, and postoperative factors.

Extended chemoprophylaxis is recommended for high-risk patients following pancreatectomy for malignancy. However, quantifying risk remains difficult. We sought to (a) identify factors associated with post-discharge venous thromboembolism (VTE) following pancreatectomy for malignancy and (b) develop a post-discharge VTE risk calculator to identify high-risk patients. Patients who underwent pancreatectomy for malignant histology from 2014 to 2018 were identified from the ACS NSQIP pancreatectomy procedure targeted dataset. Preoperative, intraoperative, and postoperative factors known at hospital discharge were evaluated for association with post-discharge VTE via multivariable logistic regression. A post-discharge VTE risk calculator was developed and validated. Of 19 340 analyzed patients, 280 (1.5%) developed post-discharge VTE. Post-discharge VTE was associated with increasing body mass index (BMI; eg, morbidly obese BMI odds ratio [OR]: 1.99 [95% confidence interval {CI}: 1.30-3.02] vs normal BMI), procedure type (distal pancreatectomy OR: 1.47 [95% CI: 1.02-2.12] vs pancreaticoduodenectomy), pancreatic fistula (OR: 1.59 [95% CI: 1.19-2.13]) and delayed gastric emptying (OR: 1.81 [95% CI: 1.29-2.52]). Patients' predicted probability of post-discharge VTE ranged from 0.7% to 9.0%. Twenty iterations of 10-fold cross-validation demonstrated internal validity. Preoperative, intraoperative, and postoperative factors were associated with post-discharge VTE following pancreatectomy for malignancy. This post-discharge VTE risk calculator allows for quantification of individual post-discharge VTE risk, which ranged from 0.7% to 9.0%.

Risk of venous thromboembolism, use of enoxaparin and clinical outcomes in obese patients undergoing laparoscopic adjustable gastric band surgery

There is a lack of clear guidance for the prophylactic use of anticoagulants for patients undergoing laparoscopic adjustable gastric banding (LAGB) surgery.This study aimed to evaluate the risk of venous thromboembolism (VTE), prophylactic use of enoxaparin and clinical outcomes in patients undergoing primary and revisional LAGB procedures.A retrospective study evaluated the prophylactic use of enoxaparin in adult patients who underwent primary and revisional (band and port) LAGB procedures. The incidence of VTE and major bleeding was investigated during a 90-day follow-up period. Descriptive and inferential statistics were used for data analysis.We included 112 and 100 patients who had undergone primary and revisional (24 band procedures and 76 port procedures) LAGB surgery, respectively. The majority of patients (97%) had a mild risk of VTE development using a post-discharge VTE risk calculator tool published from the Cleveland Clinic. All primary procedure patients received prophylactic enoxaparin, compared to 79% and 20% of revisional patients who underwent band and port procedures, respectively (P < .001). The overall VTE incidence was 0.9%, with no significant difference between patients who did or did not receive chemoprophylaxis (0.7% and 1.5%, respectively; P = .58). No major bleeding events were observed.Chemoprophylaxis may not be required in all patients undergoing low-risk LAGB surgery unless there are additional risk factors, such as the presence of super-super-morbid obesity or concomitant hormone replacement therapy. More studies are needed on the prophylactic use and dosing of enoxaparin in patients undergoing LAGB procedures to provide high-level evidence.

Extended Venous Thromboembolism Prophylaxis in Medically Ill Patients: An NATF Anticoagulation Action Initiative

Hospitalized patients with acute medical illnesses are at risk for venous thromboembolism (VTE) during and after a hospital stay. Risk factors include physical immobilization and underlying pathophysiologic processes that activate the coagulation pathway and are still present after discharge. Strategies for optimal pharmacologic VTE thromboprophylaxis are evolving, and recommendations for VTE prophylaxis can be further refined to protect high-risk patients after hospital discharge.An early study of extended VTE prophylaxis with a parenteral agent in medically ill patients yielded inconclusive results with regard to efficacy and bleeding. In the Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial, extended use of betrixaban halved symptomatic VTE, decreased hospital readmission, and reduced stroke and major adverse cardiovascular events compared with standard enoxaparin prophylaxis. Based on findings from APEX, the Food and Drug Administration approved betrixaban in 2017 for extended VTE prophylaxis in acute medically ill patients. In the Reducing Post-Discharge Venous Thrombo-Embolism Risk (MARINER) study, extended use of rivaroxaban halved symptomatic VTE in high-risk medical patients compared with placebo. In 2019, rivaroxaban was approved for extended thromboprophylaxis in high-risk medical patients, thus making available a new strategy for in-hospital and post-discharge VTE prevention.To address the critical unmet need for VTE prophylaxis in medically ill patients at the time of hospital discharge, the North American Thrombosis Forum (NATF) is launching the Anticoagulation Action Initiative, a comprehensive consensus document that provides practical guidance and straightforward, patient-centered recommendations for VTE prevention during hospitalization and after discharge.

1040 – Development of a Patient-Centered, Post-Discharge Venous Thromboembolism Risk Calculator Following Resection for Colorectal Cancer

1040 – Development of a Patient-Centered, Post-Discharge Venous Thromboembolism Risk Calculator Following Resection for Colorectal Cancer

Proportion of US Hospitalized Medically Ill Patients Who May Qualify for Extended Thromboprophylaxis.

Extended thromboprophylaxis with oral anticoagulation can reduce the risk of symptomatic venous thromboembolism (VTE) in high-risk patients. We sought to estimate the proportion of medically ill patients in the United States who might qualify for extended thromboprophylaxis according to the criteria used in the Medically-Ill Patient Assessment of Rivaroxaban versus Placebo in Reducing Post-Discharge Venous ThromboEmbolism Risk (MARINER) trial. We analyzed 2014 National Inpatient Sample (NIS) data that provide a 20% weighted annual sample of all discharges from US acute-care hospitals. Hospitalizations for acute medically ill patients were identified as those with a primary discharge diagnosis code for heart or respiratory failure, ischemic stroke, infection, or inflammatory diseases. Patients were excluded if they were <40 years old, admitted for surgery or trauma, had a length of stay <3- or >35-days, or were contraindicated to nonvitamin K antagonist oral anticoagulants. The modified International Medical Prevention Registry on Venous Thromboembolism (IMPROVE)-VTE score was used to stratify patients’ risk for postdischarge VTE, with a score of 2 to 3 suggesting patients were at moderate- and ≥4 as high-risk. Of the 35 358 810 hospitalizations in the 2014 NIS, 1 849 535 were medically ill patients admitted for heart failure (10.1%), respiratory failure (12.2%), ischemic stroke (8.8%), infection (58.5%), or inflammatory diseases (10.4%). The modified IMPROVE-VTE score classified 1 186 475 (64.1%) of these hospitalizations as occurring in moderate-risk and 407 095 (22.0%) in high-risk patients. This real-world study suggests a substantial proportion of acute medically ill patients might benefit from extended thromboprophylaxis using the modified IMPROVE-VTE score and clinical elements of the MARINER trial.

Timing and Risk Factors Associated With Venous Thromboembolism After Lung Cancer Resection

Few studies have examined the risk factors for and timing of venous thromboembolism (VTE) in patients undergoing surgical procedures for lung cancer, and there are limited data to formulate guidelines for extended VTE prophylaxis after hospital discharge. This study sought to identify risk factors for postdischarge VTE after lung resection. Patients undergoing anatomic resection for lung cancer were identified in the National Surgical Quality Improvement Program database from 2005 to 2015. Patients' demographic and clinical characteristics were evaluated for any association with postdischarge VTE. Predictors of postdischarge VTE were identified using multivariable analysis. VTE occurred in 1.6% (234) of the 14,308 patients identified; 44% (102) VTE events occurred after hospital discharge. Undergoing pneumonectomy was associated with a threefold increased risk for postdischarge VTE compared with lobectomy (2.0% versus 0.6%, p < 0.01), as was open resection compared with minimally invasive resection (0.8% versus 0.6%, p < 0.01). Prolonged operative time (>75th percentile) was also associated with an increased risk for postdischarge VTE compared with shorter operative time. Multivariable analysis identified older age, obesity, pneumonectomy, and prolonged operative time as independent predictors of postdischarge VTE. Significant proportions of VTE events occur after hospital discharge. Although there are data to suggest that the risk for VTE extends beyond this period, few patients are managed with postdischarge prophylaxis. These data suggest that postdischarge prophylaxis should be considered for those patients at high risk for VTE, particularly for older patients, those who are obese, and after extended or lengthy resections.

Identification of patients at high risk for post-discharge venous thromboembolism after hepato-pancreato-biliary surgery: which patients benefit from extended thromboprophylaxis?

BackgroundThe objective of the current study was to define risk factors associated with the 30-day post-operative risk of VTE after HPB surgery and create a model to identify patients at highest risk of post-discharge VTE. MethodsPatients who underwent hepatectomy or pancreatectomy in the ACS-NSQIP Participant Use Files 2011–2015 were identified. Logistic regression modeling was used; a model to predict post-discharge VTE was developed. Model discrimination was tested using area under the curve (AUC). ResultsAmong 48,860 patients, the overall 30-day incidence of VTE after hepatectomy and pancreatectomy was 3.2% (n = 1580) with 1.1% (n = 543) of VTE events occurring after discharge. Patients who developed post-discharge VTE were more likely to be white, had a higher median BMI, have undergone pancreatic surgery, had longer median operative times, and to have had a transfusion. A weighted prediction model demonstrated good calibration and fair discrimination (AUC = 0.63). A score of ≥−4.50 had maximum sensitivity and specificity, resulting in 44% of patients being treating with prophylaxis for an overall VTE risk of 1.1%. ConclusionsUtilizing independent factors associated with post-discharge VTE, a prediction model was able to stratify patients according to risk of VTE and may help identify patients who are most likely to benefit from pharmacoprophylaxis.

Which Patients Require Extended Thromboprophylaxis After Colectomy? Modeling Risk and Assessing Indications for Post-discharge Pharmacoprophylaxis.

Given the conflicting nature of reported risk factors for post-discharge venous thromboembolism (VTE) and unclear guidelines for post-discharge pharmacoprophylaxis, we sought to determine risk factors for 30-day post-discharge VTE after colectomy to predict which patients will benefit from post-discharge pharmacoprophylaxis. Patients who underwent colectomy in the American College of Surgeons National Surgical Quality Improvement Project Participant Use Files from 2011 to 2015 were identified. Logistic regression modeling was used. Receiver-operating characteristic curves were used and the best cut-points were determined using Youden'sJ index (sensitivity+specificity-1). Hosmer-Lemeshow goodness-of-fit test was used to test model calibration. A random sample of 30% of the cohort was used as a validation set. Among 77,823 cases, the overall incidence of VTE after colectomy was 1.9%, with 0.7% of VTE events occurring in the post-discharge setting. Factors associated with post-discharge VTE risk including body mass index, preoperative albumin, operation time, hospital length of stay, race, smoking status, inflammatory bowel disease, return to the operating room and postoperative ileus were included in logistic regression equation model. The model demonstrated good calibration (goodness of fit P=0.7137) and good discrimination (area under the curve (AUC)=0.68; validation set, AUC=0.70). A score of ≥-5.00 had the maxim sensitivity and specificity, resulting in 36.63% of patients being treated with prophylaxis for an overall VTE risk of 0.67%. Approximately one-third of post-colectomy VTE events occurred after discharge. Patients with predicted post-discharge VTE risk of ≥-5.00 should be recommended for extended post-discharge VTE prophylaxis.

Who Should Get Extended Thromboprophylaxis After Bariatric Surgery?: A Risk Assessment Tool to Guide Indications for Post-discharge Pharmacoprophylaxis.

To determine the risk factors for 30-day postdischarge venous thromboembolism (VTE) after bariatric surgery and to identify potential indications for extended pharmacoprophylaxis. VTE is among most common causes of death after bariatric surgery. Most VTEs occur after hospital stay; still a few patients receive extended pharmacoprophylaxis postdischarge. From American College of Surgeons-National Surgical Quality Improvement Program, we identified 91,963 patients, who underwent elective primary and revisional bariatric surgery between 2007 and 2012. Regression-based techniques were used to create a risk assessment tool to predict risk of postdischarge VTE. The model was validated using the 2013 American College of Surgeons-National Surgical Quality Improvement Program dataset (N = 20,575). Significant risk factors were used to create a user-friendly online risk calculator. The overall 30-day incidence of postdischarge VTE was 0.29% (N = 269). In those experiencing a postdischarge VTE, mortality increased about 28-fold (2.60% vs 0.09%; P < 0.001). Among 45 examined variables, the final risk-assessment model contained 10 categorical variables including congestive heart failure, paraplegia, reoperation, dyspnea at rest, nongastric band surgery, age ≥60 years, male sex, BMI ≥50 kg/m, postoperative hospital stay ≥3 days, and operative time ≥3 hours. The model demonstrated good calibration (Hosmer-Lemeshow goodness-of-fit test, P = 0.71) and discrimination (c-statistic = 0.74). Nearly 2.5% of patients had a predicted postdischarge VTE risk >1%. More than 80% of post-bariatric surgery VTE events occurred post-discharge. Congestive heart failure, paraplegia, dyspnea at rest, and reoperation are associated with the highest risk of post-discharge VTE. Routine post-discharge pharmacoprophylaxis can be considered for high-risk patients (ie, VTE risk >0.4%).

Accurately Measuring Hospital Venous Thromboembolism Prevention Efforts.

This commentary discusses a cohort study published in JAMA Surgery that investigated the association between inpatient surveillance for venous thromboembolism and risk of postdischarge venous thromboembolism.

Risk of Post-Discharge Venous Thromboembolism and Associated Mortality in General Surgery: A Population-Based Cohort Study Using Linked Hospital and Primary Care Data in England

BackgroundTrends towards day case surgery and enhanced recovery mean that postoperative venous thromboembolism (VTE) may increasingly arise after hospital discharge. However, hospital data alone are unable to capture adverse events that occur outside of the hospital setting. The National Institute for Health and Care Excellence has suggested the use of primary care data to quantify hospital care-related VTE. Data in surgical patients using these resources is lacking. The aim of this study was to measure VTE risk and associated mortality in general surgery using linked primary care and hospital databases, to improve our understanding of harm from VTE that arises beyond hospital stay.MethodsThis was a longitudinal cohort study using nationally linked primary care (Clinical Practice Research Datalink, CPRD), hospital administrative (Hospital Episodes Statistics, HES), population statistics (Office of National Statistics, ONS) and National Cancer Intelligence Network databases. Routinely collected information was used to quantify 90-day in-hospital VTE, 90-day post-discharge VTE and 90-day mortality in adults undergoing one of twelve general surgical procedures between 1st April 1997 and 31st March 2012. The earliest postoperative recording of deep vein thrombosis or pulmonary embolism in CPRD, HES and ONS was counted in each patient. Covariates from multiple datasets were combined to derive detailed prediction models for VTE and mortality. Limitation included the capture of VTE presenting to healthcare only and the lack of information on adherence to pharmacological thromboprophylaxis as there was no data linkage to hospital pharmacy records.ResultsThere were 981 VTE events captured within 90 days of surgery in 168005 procedures (23.7/1000 patient-years). Overall, primary care data increased the detection of postoperative VTE by a factor of 1.38 (981/710) when compared with using HES and ONS only. Total VTE rates ranged between 3.2/1000 patient-years in haemorrhoidectomy to 118.3/1000 patient-years in esophagogastric resection. Predictors of VTE included emergency surgery (OR = 1.91 95%CI 1.60–2.28, p<0.001), age (OR = 1.02 95%CI 1.02–1.03, p<0.001), body mass index (OR = 1.03 95%CI 1.01–1.04, p<0.001), previous VTE (OR = 8.07 95%CI 6.61–9.83, p<0.001), length of stay (OR = 1.00 95%CI 1.00–1.00, p = 0.007) and cancer stages II (OR = 1.38 95%CI 1.03–1.87, p = 0.033), III (OR = 1.50 95%CI 1.11–2.01, p = 0.008) and IV (OR = 1.63 95%CI 1.03–2.59, p = 0.038). Major organ resections had the greatest odds of VTE when adjusted for other risk factors including length of hospital stay. Post-discharge VTE accounted for 64.8% (636/981) of all recorded VTE. In-hospital VTE (165.4/1000 patient-years) was recorded more frequently than post-discharge VTE (16.2/1000 patient-years). Both in-hospital (OR = 2.07 95%CI 1.51–2.85, p<0.001) and post-discharge (OR = 4.03 95%CI 2.95–5.51, p<0.001) VTE independently predicted 90-day mortality. In patients who died and VTE was recorded on HES or CPRD (n = 56), VTE was one of the causes of death in 37.5% (21/56) of cases.ConclusionsA large proportion of postoperative VTE was detected in primary care. Evaluation of linked databases was a useful way of measuring postoperative VTE at population level. These resources identified a significant association between post-discharge VTE and mortality in general surgery.

A139 - Who Should Get Extended Thromboprophylaxis After Bariatric Surgery? A Risk Assessment Tool to Guide Indications for Post-Discharge Pharmacoprophylaxis

To determine the risk factors for 30-day postdischarge venous thromboembolism (VTE) after bariatric surgery and to identify potential indications for extended pharmacoprophylaxis. VTE is among most common causes of death after bariatric surgery. Most VTEs occur after hospital stay; still a few patients receive extended pharmacoprophylaxis postdischarge. From American College of Surgeons-National Surgical Quality Improvement Program, we identified 91,963 patients, who underwent elective primary and revisional bariatric surgery between 2007 and 2012. Regression-based techniques were used to create a risk assessment tool to predict risk of postdischarge VTE. The model was validated using the 2013 American College of Surgeons-National Surgical Quality Improvement Program dataset (N = 20,575). Significant risk factors were used to create a user-friendly online risk calculator. The overall 30-day incidence of postdischarge VTE was 0.29% (N = 269). In those experiencing a postdischarge VTE, mortality increased about 28-fold (2.60% vs 0.09%; P 1%. More than 80% of post-bariatric surgery VTE events occurred post-discharge. Congestive heart failure, paraplegia, dyspnea at rest, and reoperation are associated with the highest risk of post-discharge VTE. Routine post-discharge pharmacoprophylaxis can be considered for high-risk patients (ie, VTE risk >0.4%).

Predicting the risks of venous thromboembolism versus post-pancreatectomy haemorrhage: analysis of 13 771 NSQIP patients

BackgroundThe fear of an early post-pancreatectomy haemorrhage (PPH) may prevent surgeons from prescribing post-operative venous thromboembolism (VTE) chemoprophylaxis. The primary hypothesis of this study was that the national post-pancreatectomy early PPH rate was lower than the rate of VTE. The secondary hypothesis was that patients at high risk for post-discharge VTE could be identified, potentially facilitating the selective use of extended chemoprophylaxis. Patients and methodsAll elective pancreatectomies were identified in the 2005 to 2010 American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) database. Factors associated with 30-day rates of (pre- versus post-discharge) VTE, early PPH (transfusions > 4 units within 72h) and return to the operating room (ROR) with PPH were analysed. ResultsPancreaticoduodenectomies (PD) and distal pancreatectomies (DP) numbered 9140 (66.4%) and 4631 (33.6%) out of 13771 pancreatectomies, respectively. Event rates included: VTE (3.1%), PPH (1.1%) and ROR+PPH (0.7%). PD and DP had similar VTE rates (P > 0.05) with 31.9% of VTE occurring post-discharge. Independent risk factors for late VTE included obesity [odds ratio (OR), 1.5], age ≥ 75 years (OR, 1.8), DP (OR, 2.4) and organ space infection (OR, 2.1) (all P < 0.02). ConclusionsWithin current practice patterns, post-pancreatectomy VTE outnumber early haemorrhagic complications, which are rare. The fear of PPH should not prevent routine and timely post-pancreatectomy VTE chemoprophylaxis. Because one-third of VTE occur post-discharge, high-risk patients may benefit from post-discharge chemoprophylaxis.

Thromboprophylaxis patterns, risk factors, and outcomes of care in the medically ill patient population

Medically ill, hospitalized patients are at increased risk for venous thromboembolism (VTE) after discharge. This study aimed to examine thromboprophylaxis patterns, risk factors, and post-discharge outcomes. This was a retrospective claims analysis involving administrative claims data and in-patient data abstracted from a sample of hospital charts. Patients aged ≥ 40 years hospitalized for ≥ 2 days for nonsurgical reasons between 2005 and 2009 were included. Hospital chart data were abstracted for a random sample of patients without evidence of anticoagulant use at 30 days post-discharge. The combined data determined whether in-patient thromboprophylaxis (anticoagulant or mechanical prophylaxis) reduces risk of VTE at 90 days post-discharge. Hazard ratios (HR) and odds ratios (OR) were calculated using Cox proportional hazard models and logistic regression. Of 141,628 patients in the claims analysis, 3.9% received anticoagulants (3.6% warfarin). VTE, rehospitalization, and mortality rates were 1.9%, 17.2%, and 6.2%, respectively. The strongest predictors of post-discharge VTE were history of VTE (HR=4.0, 95% confidence interval [CI]: 3.3-4.8), and rehospitalization (HR=3.9, 95% CI: 3.6-4.3). Of 504 medical charts, 209 (41.5%) reported in-patient thromboprophylaxis. There was no statistically significant difference in post-discharge VTE rates between patients who did and did not receive in-patient thromboprophylaxis. All-cause mortality was greater among patients without use of VTE prophylaxis. Utilization rates of in-hospital and post-discharge VTE prophylaxis were low. In-hospital VTE prophylaxis did not reduce the risk of post-discharge VTE in the absence of post-discharge anticoagulation. Combined in-patient and post-discharge thromboprophylaxis lowered the odds of short-term, all-cause post-discharge mortality.

Prediction of postdischarge venous thromboembolism using a risk assessment model

The risk of postdischarge venous thromboembolism (VTE) (either deep vein or pulmonary embolism) is increasingly recognized yet the prescription of postdischarge thromboprophylaxis is inconsistent. There is a paucity of information to aid clinicians in identifying surgical patients who are at increased risk for postdischarge VTE. This study aimed to determine the incidence and risk factors associated with symptomatic postdischarge VTE and develop a risk score to identify patients who may benefit from extended duration thromboprophylaxis. This was a retrospective study. All nonorthopedic cases in which the patient was discharged alive without inpatient VTE were selected from the 2005-2009 National Surgical Quality Improvement Program database. A multivariate logistic regression was used to create a risk score for postdischarge VTE prediction. The dataset was split into two-thirds for risk score development and validated in the remaining one-third. The overall incidence of early postdischarge VTE for 2005-2009 National Surgical Quality Improvement Program was 0.3%. The risk score stratified patients into low, moderate, and high risk for postdischarge VTE with the incidence based on the risk score ranging from 0.07% to 2.2%. The risk score had good predictive ability with c-statistic = 0.72 for model development and c-statistic = 0.71 in the validation dataset. Factors associated with postdischarge VTE on multivariate analysis included race, increasing age, steroid use, body mass index ≥30, malignancy, higher American Society of Anesthesiologists class, increasing operative time, length of postsurgical stay, and major postoperative complication. This novel postdischarge VTE prediction score utilizes patient, operative, and early outcome factors to accurately identify patients at increased risk of a postdischarge thromboembolic event. The development of a patient- specific postdischarge VTE risk profile may help address the challenge of determining postdischarge prophylaxis requirements.