Postoperative Venous Thromboembolic Events Research Articles

The impact of preoperative venous thromboembolism on patients undergoing TURBT: Perioperative outcomes and healthcare costs from US insurance claims data.

To assess the impact of a positive history of venous thromboembolism (VTE) on perioperative outcomes, including length of in-hospital stay, readmission rates, 90-day postoperative complications, and healthcare costs in bladder cancer (BCa) patients undergoing transurethral resection of bladder tumour (TURBT) in the United States. Patients aged ≥18 years with a BCa diagnosis undergoing TURBT were identified in the Merative® Marketscan® Research de-identified databases between 2007 and 2021. Multivariable logistic regression adjusted by relevant perioperative confounders was used to investigate the association between diagnosis of VTE before TURBT and 90-day complication rates, new postoperative VTE events, re-hospitalization, and total hospital expenditures (2021 US dollars). Sensitivity analyses on VTE severity (pulmonary embolism [PE], deep venous thrombosis [DVT] or superficial thrombophlebitis/phlebitis [SVT]), as well as TURBT extent (minor vs. major) were additionally examined. In total, 139 800 patients were identified, with 5.3% having preoperative VTE, including DVT (n = 3112, 42.20%), PE (n = 2046, 27.74%) and SVT (n = 2217, 30.06%). A history of preoperative VTE predicted higher rates of any complication (adjusted odds ratio [aOR] 1.28, 95% CI 1.14-1.43) and also higher rates of infectious and haemorrhagic complications. Additionally, preoperative VTE increased the risk of novel VTE events following TURBT (aOR 17.30, 95% CI 16.05-18.65), hospital length of stay (aOR 2.23, 95% CI 1.90-2.62), readmissions (aOR 1.47, 95% CI 1.39-1.56), and hospital associated costs (aOR 1.17, 95% CI 1.12-1.23). DVT and non-minor TURBT procedures did not increase the risk of any, infectious, or haemorrhagic complications, but other associations were maintained regardless of the severity of VTE (PE, DVT, SVT) or TURBT extent (minor/major). A history of VTE before undergoing transurethral procedures for BCa is associated with significantly worse perioperative outcomes and higher healthcare costs. These findings may help us to counsel on the risks of the intervention and hopefully improve our ability to mitigate such risks.

Statin Use is Associated with Decreased Venous Thromboembolism Events Following Total Hip Arthroplasty: A Matched Retrospective Cohort Study.

Despite advances in surgical techniques and postoperative prophylactic protocols, venous thromboembolism (VTE) events remain an important source of morbidity following total hip arthroplasty (THA). Prior research in cardiology and other surgical fields has suggested that statin medications may have a protective effect against VTE. Our study aimed to: 1) Assess if preoperative statin use was associated with decreased rates of VTE following THA, and 2) conduct a subgroup analysis of statin intensity and VTE events. A total of 1,154 patients who had preoperative statin use for at least four weeks before surgery and who underwent primary THA at a large, urban academic center between January 1, 2012, and June 1, 2023, were identified. The 90-day postoperative VTE events, deep vein thrombosis (DVT), pulmonary embolism (PE), emergency department (ED) visits, reoperations, and readmission rates were collected from institutional coding software. Mortality rate in the 90-day postoperative period was also measured. Propensity matching was used to control for demographics and selected comorbidities. Preoperative statin use was associated with significantly lower rates of 90-day VTE events (Statin: 0.43% versus No-Statin: 1.13%, P = 0.047). There were no significant differences in 90-day PE, DVT, ED visit, readmission, or reoperation rates. There were no deaths within 90 days of THA in either group. Subgroup analysis of statin intensity revealed no significant differences in any outcomes measured between high-intensity, medium-intensity, and low-intensity statin groups. Preoperative statin use is associated with significantly lower rates of VTE events in the 90-day postoperative period following THA. Further research into the effect of statins on post-THA VTE is warranted.

Venous Thromboembolism Risk Assessment in Inpatient and Ambulatory Otolaryngology Surgical Patients.

Venous thromboembolic events (VTEs) are a leading cause of postoperative morbidity, prolonged hospital stay, and increased cost. Recommendations for mechano- and chemoprophylaxis are currently based on the 2005 Caprini score, a screening tool developed to identify patients at risk for VTE. The Caprini risk assessment model (RAM) was designed for surgical impatients and has been tested in a number of surgical fields, including otolaryngology. However, the vast majority of otolaryngology cases are performed as ambulatory surgery. Simpler RAMs include the COBRA scoring system and Pannucci-NSQIP. Here, we evaluate risk stratification of otolaryngology surgical patients and correlate the findings of these three RAMs. Retrospective chart review. A retrospective chart review of 869 patients undergoing surgery by Weill Cornell faculty otolaryngologists between June and December 2022 was performed. Patient demographics, VTE risk factors, admission status, surgical subservice, and postoperative events were collected, and RAM scores were calculated for each patient. Wilcoxon and Kruskal-Wallis rank-sum tests were utilized to assess differences in VTE risk scores based on type of procedure and admission status, and Spearman's correlation was utilized to assess agreement between the three different scoring systems. Multivariate linear regressions were utilized to assess variables that impacted the Caprini, COBRA, and NSQIP RAMs. In total, two patients developed postoperative venous thromboembolism. Furthermore, there is a strong positive correlation between Caprini and COBRA RAMs (even when broken down by admission status, although it weakens in the inpatient population). There is a moderate positive correlation between Caprini and Pannucci-NSQIP in the full cohort, but that correlation is lost in the inpatient population. Otolaryngology surgical patients are at low risk of postoperative VTE. Caprini, Pannucci-NSQIP, and COBRA RAMs correlate well in determining ambulatory patients at risk for postoperative VTE and shorter, simpler RAMS such as COBRA and Pannucci-NSQIP can be used instead of Caprini RAM. 3 Laryngoscope, 2024.

Predictive modeling of lower extreme deep vein thrombosis following radical gastrectomy for gastric cancer: based on multiple machine learning methods

Postoperative venous thromboembolic events (VTEs), such as lower extremity deep vein thrombosis (DVT), are major risk factors for gastric cancer (GC) patients following radical gastrectomy. Accurately predicting and managing these risks is crucial for optimal patient care. This retrospective case‒control study involved 693 GC patients from our hospital who underwent radical gastrectomy. We collected plentiful and comprehensive clinical indicators including a total of 49 baseline, preoperative, surgical and pathological clinical data. Using univariate logistic regression, we identified potential risk factors, followed by feature selection through the Boruta algorithm. We then constructed the final predictive model using multivariate logistic regression and evaluated it using receiver operating characteristic (ROC) curve analysis, calibration plots, decision curve analysis, and other methods. Additionally, we applied various machine learning techniques, including decision trees and random forests, to assess our model’s predictive strength. This retrospective case‒control study involved 693 GC patients from our hospital who underwent radical gastrectomy. We collected plentiful and comprehensive clinical indicators including a total of 49 baseline, preoperative, surgical and pathological clinical data. Using univariate logistic regression, we identified potential risk factors, followed by feature selection through the Boruta algorithm. We then constructed the final predictive model using multivariate logistic regression and evaluated it using receiver operating characteristic (ROC) curve analysis, calibration plots, decision curve analysis, and other methods. Additionally, we applied various machine learning techniques, including decision trees and random forests, to assess our model’s predictive strength. Univariate logistic analysis revealed 14 risk factors associated with postoperative lower limb DVT. Based on the Boruta algorithm, six significant clinical factors were selected, namely, age, D-dimer (D-D) level, low-density lipoprotein, CA125, and calcium and chloride ion levels. A nomogram was developed using the outcomes from the multivariate logistic regression analysis. The predictive model showed high accuracy, with an area under the curve of 0.936 in the training set and 0.875 in the validation set. Various machine learning algorithms confirmed its strong predictive capacity. MR analysis revealed meaningful causal relationships between key clinical factors and DVT risk. Based on various machine learning methods, we developed an effective predictive diagnostic model for postoperative lower extremity DVT in GC patients. This model demonstrated excellent predictive value in both the training and validation sets. This novel model is a valuable tool for clinicians to use in identifying and managing thrombotic risks in this patient population.

The impact of venous thromboembolism before open or minimally-invasive radical cystectomy in the USA: insurance claims data on perioperative outcomes and healthcare costs.

The relationship between venous thromboembolism (VTE) and solid malignancy has been established over the decades. With rising projected rates of bladder cancer (BCa) worldwide as well as increasing number of patients experiencing BCa and VTE, our aim is to assess the impact of a preoperative VTE diagnosis on perioperative outcomes and health-care costs in BCa cases undergoing radical cystectomy (RC). Patients ≥18 years of age with BCa diagnosis and undergoing open or minimally invasive (MIS) RC were identified in the Merative™ Marketscan® Research Databases between 2007 and 2021. The association of previous VTE history with 90-day complication rates, postoperative VTE events, rehospitalization, and total hospital costs (2021 USA dollars) was determined by multivariable logistic regression modeling adjusted for patient and perioperative confounders. Sensitivity analysis on VTE degree of severity (i.e., pulmonary embolism [PE] and/or peripheral deep venous thrombosis [DVT]) was also examined. Out of 8759 RC procedures, 743 (8.48%) had a previous positive history for any VTE including 245 (32.97%) PE, 339 (45.63%) DVT and 159 (21.40%) superficial VTE. Overall, history of VTE before RC was strongly associated with almost any worse postoperative outcomes including higher risk for any and apparatus-specific 90-days postoperative complications (odds ratio [OR]: 1.21, 95% CI, 1.02-1.44). Subsequent incidence of new VTE events (OR: 7.02, 95% CI: 5.93-8.31), rehospitalization (OR: 1.25, 95% CI: 1.06-1.48), other than home/self-care discharge status (OR: 1.53, 95% CI: 1.28-1.82), and higher health-care costs related to the RC procedure (OR: 1.43, 95% CI: 1.22-1.68) were significantly associated with a history of VTE. Preoperative VTE in patients undergoing RC significantly increases morbidity, post-procedure VTE events, hospital length of stay, rehospitalizations, and increased hospital costs. These findings may help during the BCa counseling on risks of surgery and hopefully improve our ability to mitigate such risks.

Venous Thromboembolism Chemoprophylaxis Adherence Rates After Major Cancer Surgery

Venous thromboembolism (VTE) represents a major source of preventable morbidity and mortality and is a leading cause of death in the US after cancer surgery. Previous research demonstrated variability in VTE chemoprophylaxis prescribing, although it is unknown how these rates compare with performance in the Veterans Health Administration (VHA). To determine VTE rates after cancer surgery, as well as rates of inpatient and outpatient (posthospital discharge) chemoprophylaxis adherence within the VHA. This retrospective cohort study within 101 hospitals of the VHA health system included patients aged 41 years or older without preexisting bleeding disorders or anticoagulation usage who underwent surgical treatment for cancer with general surgery, thoracic surgery, or urology between January 1, 2015, and December 31, 2022. The VHA Corporate Data Warehouse, Pharmacy Benefits Management database, and the Veterans Affairs Surgical Quality Improvement Program database were used to identify eligible patients. Data analysis was conducted between January 2022 and July 2023. Inpatient surgery for cancer with general surgery, thoracic surgery, or urology. Rates of postoperative VTE events within 30 days of surgery and VTE chemoprophylaxis adherence were determined. Multivariable Poisson regression was used to determine incidence-rate ratios of inpatient and postdischarge chemoprophylaxis adherence by surgical specialty. Overall, 30 039 veterans (median [IQR] age, 67 [62-71] years; 29 386 men [97.8%]; 7771 African American or Black patients [25.9%]) who underwent surgery for cancer and were at highest risk for VTE were included. The overall postoperative VTE rate was 1.3% (385 patients) with 199 patients (0.7%) receiving a diagnosis during inpatient hospitalization and 186 patients (0.6%) receiving a diagnosis postdischarge. Inpatient chemoprophylaxis was ordered for 24 139 patients (80.4%). Inpatient chemoprophylaxis ordering rates were highest for patients who underwent procedures with general surgery (10 102 of 10 301 patients [98.1%]) and lowest for patients who underwent procedures with urology (11 471 of 17 089 patients [67.1%]). Overall, 3142 patients (10.5%) received postdischarge chemoprophylaxis, with notable variation by specialty. These findings indicate the overall VTE rate after cancer surgery within the VHA is low, VHA inpatient chemoprophylaxis rates are high, and postdischarge VTE chemoprophylaxis prescribing is similar to that of non-VHA health systems. Specialty and procedure variation exists for chemoprophylaxis and may be justified given the low risks of overall and postdischarge VTE.

Significant Variability in Postoperative Thromboprophylaxis in Cushing's Disease Patients: A Survey of the North American Skull Base Society and the AANS/CNS Joint Tumor Section.

Introduction Cushing's disease (CD) is associated with hypercoagulability which is associated with an increased risk of venous thromboembolic events (VTEs) perioperatively. This risk persists even after successful transsphenoidal surgery (TSS). However, there are no current guidelines for pharmacologic thromboprophylaxis in this patient population. Objective Characterize existing thromboprophylaxis management practices in patients undergoing TSS for CD. Methods An anonymous RedCap survey comprised of questions about perioperative thromboprophylaxis in CD patients was distributed via the American Association of Neurological Surgeons (AANS)/Congress of Neurological Surgeons (CNS) Joint Tumor Section and the North American Skull Base Society (NASBS) email lists. Results The survey was distributed to 554 members of the AANS/CNS Joint Tumor Section and 1,094 members of NASBS asking that members who surgically treat CD respond. Sixty responses (3.0% response rate) were received. Fifty-two (86.7%) respondents are involved in the postoperative management of CD patients. Thirty-six (69.2%) treat all patients with postoperative VTE chemoprophylaxis, 8 (15.4%) treat some patients, while 8 (15.4%) do not use chemoprophylaxis. Preferred chemoprophylaxis varies as 26 (59.1%) administer low molecular weight heparin, 14 (31.8%) give unfractionated heparin, 1 (2.3%) give direct oral anticoagulants, and 3 (6.8%) give aspirin. Most (28, 53.8%) of the respondents perceive the VTE risk in this patient population to be 0 to 5%, 16 (30.8%) perceive the risk to be 6 to 10%, and 8 (15.4%) perceive it to be 11 to 20%. Conclusion There is great variability in VTE detection and postoperative prevention practice patterns in CD patients. This study highlights the need for prospective studies to clarify optimal pharmacologic chemoprophylaxis strategies and duration in this patient population.

Revisiting Anticoagulation in Spine Surgery: Balancing Venous Thromboembolic Events and Epidural Hematoma.

Retrospective Cohort Study. Venous thromboembolic events (VTE) and post-operative epidural hematoma (EDH) are significant complications after spine surgery. Guidelines for chemoprophylaxis are controversial and variability amongst surgeons remains. The objective of this study was to establish the incidence of clinical VTE and EDH at our institution and evaluate the association of chemoprophylaxis with clinical VTE and EDH. We conducted a retrospective cohort study of patients undergoing spine surgery at a high-volume tertiary care center in Seattle, WA between January 2016 and December 2019. The Premier Health Care Database and Agency for Healthcare Research and Quality (AHRQ) patient indicators PSI-9 (Perioperative hemorrhage and hematoma) and PSI-12(Perioperative PE or DVT) were used to identify patients experiencing VTE and/or post-operative EDH. The primary outcome was the incidence of clinical VTE and EDH in post-operative spine patients. Secondary outcomes included the association of chemoprophylaxis with clinical VTE and EDH. From 2016 to 2019, 4587 patients underwent spine surgery, totaling 4764 hospital stays. The incidence of clinical VTE was .21% (10/4764) and the incidence of EDH was .10% (5/4764). Most hemorrhages occurred prior to the initiation of chemoprophylaxis. One patient with EDH received chemoprophylaxis prior to hemorrhage. The rate of post-operative clinical VTE and EDH in spine surgery is low. Despite early initiation of chemoprophylaxis after major spine surgery we did not appreciate a high rate of EDH. We attribute our low rate of clinical VTE to multimodal prophylaxis with SCDs, early mobilization and chemoprophylaxis on post-operative day 1.

Assessment of Postoperative Venous Thromboembolic Complications

BACKGROUND: Postoperative venous thromboembolic events (VTEs) are a preventable cause of death. Adherence to available guidelines and prophylactic measures is suboptimal. This study examined postoperative VTEs prevalence, prophylaxis guideline adherence, and VTEs risk factors among surgical patients at King Abdulaziz University Hospital in Saudi Arabia. METHODOLOGY: This retrospective study analyzed VTEs patients from August 2020 to November 2022. Medical records collected data on patients, procedures, prevention, guideline adherence, and VTEs diagnosis. The statistical analysis evaluated the link between prophylactic measures and VTEs occurrence. RESULTS: Thirty-one (32%) of the 97 VTEs diagnosed in patients were postoperative VTEs. Mortality rates were 18.5%, and for postoperative VTEs patients were 12.9%. Most patients (87.1%) were at high risk (Caprini score ≥ 5) for VTEs. Abdominopelvic procedures were 64.5% of cases. Approximately 60% of patients received postoperative prophylaxis. Enoxaparin was the most frequently used prophylaxis method (63.1%). Mechanical prophylaxis was used in 36.8% of patients who received prophylaxis. Compliance for extended prophylaxis was only 10.5%. Late initiation of prophylactic measures was significantly associated with deep vein thrombosis occurrence. CONCLUSION: The study emphasizes the need to follow prophylaxis guidelines. Improving compliance with prophylactic measures, especially for high-risk patients, can potentially reduce postoperative VTEs.

Venous Thromboembolic Event Following Soft Tissue Sarcoma Diagnosis is Associated with the Development of Pulmonary Metastasis.

This study aimed to investigate whether venous thromboembolic events (VTEs) are clinically relevant predictors of pulmonary metastatic disease in patients with soft tissue sarcomas (STSs). In this retrospective cohort analysis, we included patients with STS surgically treated for sarcoma between January 2002 and January 2020. The primary outcome of interest was development of pulmonary metastasis after non-metastatic STS diagnosis. Tumor depth, stage, type of surgical intervention, chemotherapy, radiation therapy, body mass index, and smoking status were collected. Episodes of VTEs following STS diagnosis, including deep vein thrombosis, pulmonary embolism, and other thromboembolic events, were also obtained. Univariate analyses and multivariable logistic regression were used to identify potential predictors for pulmonary metastasis. We included 319 patients with mean age of 54.9±16 years. Thirty-seven patients (11.6%) had VTE after STS diagnosis, and 54 (16.9%) developed pulmonary metastasis. Univariate screening revealed pulmonary metastasis, pre- and postoperative chemotherapy, smoking history, and VTE after surgery as potential predictors of pulmonary metastasis. Multivariable logistic regression revealed smoking history [odds ratio (OR) 2.0, confidence interval (CI) 1.1-3.9, P=0.04] and VTE (OR 6.3, CI 2.9-13.6, P<0.001) as independent risk factors for predicting pulmonary metastasis in patients with STS, after adjusting for the factors in the univariate screening as well as age, sex, stage of the tumor, and neurovascular invasion. Patients with VTE after STS diagnosis have an odds ratio of 6.3 for developing metastatic pulmonary disease compared with patients without venous thromboembolic events. Smoking history was also associated with future pulmonary metastases.

Incidence and associated risk factors of venous thromboembolism after open and laparoscopic partial nephrectomy in patients administered short-period thromboprophylaxis: a Danish nationwide population-based cohort study

Objective To report the risk of venous thromboembolism (VTE) after partial nephrectomy in Denmark. Materials and methods A nationwide population-based registry was used to conduct a retrospective cohort study. All partial nephrectomies from January 2010 to August 2018 were assessed for postoperative VTE events. Univariable and multivariable analyses were used to evaluate the odds of postoperative VTE within 4 weeks and 4 months after partial nephrectomy in patients who received standard-of-care thromboprophylaxis. Results Among 2355 patients, postoperative VTE risk was 0.6% and 0.9%, at 4 weeks and 4 months, respectively. In multivariate analysis, prior VTE (OR = 24.9, p < 0.001) and length of hospital stay (OR = 0.89, p < 0.001) were predictors of postoperative VTE within 4 months after partial nephrectomy. Limitations included the retrospective and registry-based study design and the absence of BMI data. Conclusion Incidence of postoperative VTE is rare, but patients with prior VTE and those with a greater length of hospital stay are at greater long-term risk and should be evaluated when considering thromboprophylaxis.

Risk factors of venous thromboembolism after incisional ventral hernia repair.

The problem of venous thromboembolic events (VTE) after incisional hernia repair remains relevant. According to the literature the frequency of VTE ranges from 0.2 to 4.2%. The data on risk factors of VTE in this cohort of patients are scarce. Aim of our study is to find frequency and risk factors for VTE development in patients who underwent surgery for incisional ventral hernia. There were 240 patients enrolled in our retrospective study. We included patients, who were operated for incisional hernia in Saveljev University Surgery Clinic from January 2018 to December 2019. Compression duplex ultrasound of lower extremity veins was performed within median 3days (min 1day, max 7days) after surgery for all participants. The primary endpoint was the occurrence of the VTE event, including deep venous thrombosis (DVT) and pulmonary embolism (PE). VTE was detected in 19 patients, which accounted for 7.9% in analyzed cohort. All patients received standard pharmacological prophylaxis. There were 3 (1.3%) proximal, 16 (6.7%) distal DVT, in one patient (0.4%) distal thrombosis was complicated by symptomatic pulmonary embolism. In multivariate Cox proportional hazard model was found that component separation (HR 3.99, 95% CI 1.14-14.0, p = 0.03), duration of operation in hours (HR 1.67. 95% CI 1.13-2.5, p = 0.011) and body mass index (HR 1.13, 95% CI 1.02-1.2, p = 0.02) were statistically significant risk factors. The incidence of postoperative VTE in patients after incisional hernia repair is high with a predominant distal DVT as a thrombotic event. Component separation, duration of operation and body mass index are statistically significant factors of VTE in patients undergoing surgery for incisional hernia.

Dose-dependent effects of red blood cell transfusion and case mix index on venous thromboembolic events in spine surgery.

Venous thromboembolic (VTE) events represent a major source of morbidity and mortality in spine surgery. Our goal was to assess whether a dose-response relationship exists between red blood cell (RBC) transfusion and postoperative VTE events among spine surgery patients. A total of 786 spine surgery patients at a single institution who received at least 1 RBC unit perioperatively were included (2016-2019). Patients were stratified based on RBC transfusion volume: 1-2 units (39.3%), 3-4 units (29.4%), 5-6 units (15.9%) and ≥7 units (15.4%). Subgroup analyses were performed after stratification by case mix index, a standardized surrogate for patients' disease severity and comorbidities. Multivariable regression was used to assess risk factors for the development of postoperative VTE events. The overall VTE event rate was 2.4% (n=19). A dose-response relationship was seen between RBC transfusion volume and VTE events (1-2 units: 0.97%, 3-4 units: 1.30%, 5-6 units: 3.20%, ≥7 units: 7.44%; p < 0.01). Similar dose-response relationships were seen between case mix index and VTE events (1.00-3.99: 0.52%, 4.00-6.99: 2.68%, ≥7.00: 9.00%; p < 0.01). On multivariable regression, larger RBC transfusion volumes (adjusted odds ratio [OR] 1.18 per RBC unit, 95% confidence interval [CI] 1.07-1.29; p < 0.01) and higher case mix index scores (adjusted OR 1.39 per unit increase, 95% CI 1.14-1.69; p < 0.01) were associated with an increased risk of thrombosis. Larger RBC transfusion volumes and higher case mix index scores were associated with an increased risk of VTE events. Physicians should be aware of how these dose-response relationships can influence a patient's risk of developing thrombotic complications postoperatively.

Impact of Prolonged Operative Duration on Postoperative Symptomatic Venous Thromboembolic Events After Thoracolumbar Spine Surgery

To determine the effect of operative duration on the rate of postoperative symptomatic venous thromboembolic (VTE) events in patients undergoing thoracolumbar spine fusion. We identified all thoracolumbar spine fusion patients between 2012 and 2021. Operative duration was defined as time from skin incision to skin closure. A 1:1 propensity match was conducted incorporating patient and surgical characteristics. Logistic regression was performed to assess predictors of postoperative symptomatic VTE events. A receiver operating characteristic curve was created to determine a cutoff time for increased likelihood of VTE. We identified 101 patients with VTE and 1108 patients without VTE. Seventy-five patients with VTE were matched to 75 patients without VTE. Operative duration (339 vs. 262 minutes, P= 0.010) and length of stay (5.00 vs. 3.54 days, P= 0.008) were significantly longer in patients with a VTE event. Operative duration was an independent predictor of VTE on multivariate regression (odds ratio: 1.003, 95% confidence interval: 1.001-1.01, P= 0.021). For each additional hour of operative duration, the risk of VTE increased by 18%. A cutoff time of 218 minutes was identified (area under the curve [95% confidence interval]= 0.622 [0.533-0.712]) as an optimal predictor of increased risk for a VTE event. Operative duration significantly predicted symptomatic VTE, especially after surgical time cutoff of 218 minutes. Each additional hour of operative duration was found to increase VTE risk by 18%. We also identify the impact of VTE on 90-day readmission rates, suggesting significantly higher costs and opportunity for hospital acquired conditions, in line with prior literature.

Abdominal Plication & Postoperative Venous Thromboembolic Events Following Abdominal Body Contouring: A Propensity Score Matching Analysis

Abdominal Plication & Postoperative Venous Thromboembolic Events Following Abdominal Body Contouring: A Propensity Score Matching Analysis

Abdominal Plication and Postoperative Venous Thromboembolic Events after Abdominal Body Contouring: A Propensity Score Matching Analysis

INTRODUCTION: Abdominal plication may increase intra-abdominal pressure (IAP). Although concerns that elevated IAP may increase venous thromboembolic events (VTEs) exist, there is a lack of literature investigating this association. METHODS: A retrospective review of all patients who underwent abdominal body contouring at our institution between 2010 and 2020 was completed. Cases were those with postoperative VTEs and were matched to controls (1:4) using propensity score matching techniques. Variables collected include demographic data, operative details, comorbidity indices, and postoperative complications. Parametric, nonparametric, and multivariable regression modeling were used for analysis. RESULTS: Overall, 1,192 patients were included; 19 (1.59%) experienced a postoperative VTE and were matched to 76 controls. The matched cohort was 92.6% female with the average age, Charlson comorbidity index, BMI, and operative time being 44.99 years, 1.38 points, 30.25 units, and 284.69 minutes. BMI differed significantly between cases and controls (32.1 vs 29.8, p = 0.046), as did history of cerebrovascular events (OR: 3.45, p = 0.026). Additionally, patients with postoperative VTEs were more likely to have received intraoperative blood transfusions (OR: 13.88, p = 0.005). Postoperatively, cases had significantly longer LOS (6.21 vs 1.21, p = 0.006) and a much longer duration of chemophylaxis (6.05 vs 1.46, p = 0.015). Cases were significantly more likely to experience concurrent complications including infection, delayed wound healing, and umbilical necrosis (p < 0.001, p = 0.044, p = 0.044). Plication was not associated with VTE outcomes. CONCLUSION: Abdominal plication does not increase the risk of VTEs. However, in patients who do experience VTEs, further caution must be exercised because there is an increased likelihood of concurrent complications.

Peri-operative thrombophilia in patients undergoing liver resection for colorectal metastases

BackgroundRoutine chemical venous thromboembolism (VTE) prophylaxis for liver surgery remains controversial, and often delayed post-operatively due to perceived bleeding risk. This study asked whether patients undergoing hepatectomy for colorectal metastases (CRM) were at risk from VTE pre-operatively, and the impact of hepatectomy on that risk. MethodsSingle-centre prospective observational cohort study of patients undergoing open hepatectomy for CRM, comparing pre-, peri- and post-operative haemostatic variables. ResultsOf 336 hepatectomies performed October 2017–December 2019, 60 resections in 57 patients were recruited. There were 28 (46.7%) major resections, with median (interquartile range [IQR]) blood loss 150.0 (76.3–263.7) mls, no blood transfusions, post-operative VTE events or deaths. Patients were prothrombotic pre-operatively (high median factor VIIIC and increased thrombin generation velocity index), an effect exacerbated post-hepatectomy. Major hepatectomies had a significantly greater median drop in Protein C, rise in Factor VIIIC and von Willebrand Factor, versus minor resections (p = 0.001, 0.005, 0.001 respectively). Patients with parenchymal transection times greater than median (40 min), had significantly increased median (IQR) PMBC-TFmRNA expression [1.65(0.93–2.70)2ddCt], versus quicker transections [0.99(0.69–1.28)2ddCt, p = 0.020]. ConclusionsPatients with CRM are prothrombotic pre-operatively, an effect exacerbated by hepatectomy, particularly longer, complex resections, suggesting chemical thromboprophylaxis be considered early in the patient pathway.

P144. The effect of operative duration on postoperative VTE rates in spinal surgery

<h3>BACKGROUND CONTEXT</h3> The relationship between operative duration and its effect on postoperative venous thromboembolism (VTE) remains unclear in spine surgery. Previous studies have been limited in cohort size or have lacked adequate variability of surgical duration to determine the extent of effect surgery length has on VTE rates. Information regarding patient demographics and the effect of surgical durations on VTE are critical to establish appropriate guidelines for determining which patients could benefit from postoperative chemoprophylaxis. <h3>PURPOSE</h3> To determine the effect of operative duration on postoperative VTE rates in patients undergoing elective thoracolumbar spinal procedures. <h3>STUDY DESIGN/SETTING</h3> Retrospective cohort study. <h3>PATIENT SAMPLE</h3> Patients >18 years of age who underwent thoracolumbar spinal fusion between 2007-2021 were retrospectively identified. A 10:1 propensity match incorporating patient demographics and surgical characteristics was conducted to match and compare patients for postoperative VTE events. <h3>OUTCOME MEASURES</h3> Postoperative VTE events, cut-to-close duration, prior history of clots, Oswestry Disability Index (ODI), Mental (MCS-12) and Physical (PCS-12) Component Summary of the Short-Form 12, visual analog scale (VAS) Back, VAS Leg. <h3>METHODS</h3> A structured query language (SQL) search was used to identify patients who underwent a thoracolumbar surgery and had a postoperative VTE. Only patients with deep VTEs were included. Demographics, surgical characteristics and patient reported outcome measures (PROMs) were collected from the electronic medical record. Patients were categorized into a VTE and non-VTE group. Categorical comparisons were analyzed using Pearson chi-square analysis or Fisher's Exact test. Continuous variables were analyzed using independent samples t-test or Mann-Whitney U test. A binary logistic regression was then performed to determine if cut-to-close duration was a predictor of increased postoperative VTE events—controlling for demographics and a history of clots. A receiver operating characteristic (ROC) curve using Youden's index was created to determine a "cutoff" time for predicting increased likelihood of a VTE based on surgical duration. <h3>RESULTS</h3> A total of 1,456 patients (122 VTE, 1,334 non-VTE) were included. The VTE group was younger (61.5 vs 65.5, p<0.001), predominantly male (60.8% vs 44.5%, p=0.001), experienced a previous VTE (15.6% vs 2.92%, p<0.001) and had higher cut-to-close time (304 mins vs 209 mins, p<0.001). However, there was no difference in CCI between groups (1.08 vs 0.66, p=0.119). When evaluating PROMs, the VTE group had worse 1-year postoperative minus preoperative (∆) ODI (-11.79 vs -21.99, p=0.039), ∆PCS-12 (4.30 vs 8.52, p=0.045), and ∆VAS Leg (-1.41 vs -4.08, p=0.001). Operative duration was an independent predictor of increased postoperative VTE rates on bivariate regression analysis (β=0.01, p<0.001). When evaluating the ROC, a cutoff time of 245 mins was identified (AUC [95% CI] = 0.672 [0.615 – 0.728]) as an optimal predictor of increased risk for a VTE. <h3>CONCLUSIONS</h3> A history of a prior VTE was associated with greater VTE rates during elective thoracolumbar surgery. Patients with a VTE had worse 1-year ∆ODI, ∆PCS-12, and ∆VAS Leg indicating that patients have worse overall improvement after VTE development, even after the VTE has been treated. Additionally, a higher operative duration is an independent risk factor for postoperative VTE. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Electronic health record risk-stratification tool reduces venous thromboembolism events in surgical patients

BackgroundVenous thromboembolism is a preventable cause of morbidity and mortality after surgery. To ensure that patients receive appropriate venous thromboembolism chemoprophylaxis, a nonmandatory risk-stratification tool based on patient clinical condition was implemented through the electronic health record to stratify patient risk and recommend chemoprophylaxis. We hypothesized that implementing this tool would reduce postoperative venous thromboembolism events in general surgery as well as across all surgical services. MethodsAll adult patients undergoing inpatient surgical operations (January 2012–December 2019) at a single quaternary care center and Level 1 trauma center were abstracted from institutional electronic health record database and stratified into patients admitted before and after venous thromboembolism risk-stratification tool implementation. Bivariable analyses compared venous thromboembolism chemoprophylaxis prescription and venous thromboembolism events with implementation and screening among all surgical patients as well as in general surgery patient subset. ResultsA total of 64,377 adults underwent operations: 27,819 preimplementation and 36,558 postimplementation. A significant reduction in venous thromboembolism events occurred from pre- to post-tool implementation for all cases (0.77% vs 0.47%, P < .001). General surgery patients (n = 15,723) had a significant increase in chemoprophylaxis prescription (81.9% vs 86.0%, P < .001) and a significant reduction in venous thromboembolism events (1.41% vs 0.59%, P < .001). After tool implementation, use of extended postdischarge chemoprophylaxis was greater among general surgery patient subset than the entire patient cohort (46.7% vs 29.6%, P < .001). ConclusionThe integration of a nonmandatory electronic health record risk-stratification tool was associated with a significant reduction in venous thromboembolism events. Extended chemoprophylaxis was prescribed in nearly half of general surgery patients at very high risk for postdischarge events.

Coronavirus infection and risk of postoperative venous thromboembolic events

To determine whether patients with perioperative or previous coronavirus infection (CVI) have a greater risk of venous thromboembolic events (VTE). A multiple-center regional prospective retrospective cohort study included elective and emergency patients who underwent surgery in November 2020. The primary endpoint was VTE (PE/DVT) within 30 days after surgery. CVI was stratified as perioperative (7 days before surgery - 30 days after surgery), recent (1-6 weeks before surgery) and remote (≥7 weeks before surgery) infection. There was no information about prevention or preoperative anticoagulation at baseline data collection. Incidence of postoperative VTE was 1.5% (10/650) in patients without CVI, 33.3% (3/9) in patients with perioperative CVI, 18.1% (2/11) in patients with recent CVI and 8.3% (1/12) in patients with remote CVI. After adjusting the confounders, patients with perioperative and recent CVI remained at a higher risk of VTE. In general, VTEs were independently associated with 30-day mortality. In patients with CVI, mortality rate among ones without VTE was 21.7% (5/23), with VTE - 44.4% (4/9). Patients with perioperative CVI have a higher risk of postoperative VTE compared to those without CVI and patients with previous CVI and no residual symptoms. Mortality in this group is also higher than in other cohorts.