Development Of Postoperative Venous Thromboembolism Research Articles

Impact of Reduced Enoxaparin Prophylactic Dosing on Bleeding and Thrombotic Risk for Low Body Weight Post-Operative Colorectal Surgery Patients.

Introduction: Colorectal surgery (CORS) patients are at the highest risk of any general surgery population for the development of post-operative venous thromboembolism (VTE) and are also at an increased risk for post-operative bleeding, especially with procedures related to early cancer stages. Low molecular weight heparin (LMWH) is recommended for VTE prophylaxis in this surgical population. Current guidelines and primary literature along with institutional protocols support dosage adjustments for obesity and impaired renal function, but literature providing optimal VTE prophylactic LMWH dosing is extremely limited for underweight, surgical patients. Objectives: The aim of this study was to evaluate both bleeding and VTE rates for hospitalized underweight colorectal surgery patients receiving post-operative VTE prophylaxis with standard enoxaparin 40 mg subcutaneously (SQ) every 24 hours versus reduced dose enoxaparin 30 mg SQ every 24 hours. Methods: This trial was a multicenter, retrospective chart review with data collected on post-operative CORS patients over a 10-year period. Patients were included if aged 18 years and older, weighed less than 50 kg, and received at least 1 dose of enoxaparin 40 mg or 30 mg post-operatively. The primary endpoint was a descriptive comparison of post-operative bleeding with use of standard enoxaparin 40 mg SQ every 24 hours compared to reduced dose enoxaparin 30 mg SQ every 24 hours for post-operative VTE prophylaxis. The secondary endpoint was the descriptive comparison of post-operative thrombotic event rates in the same population. Results: The total population investigated included 146 patients. One hundred twenty-nine (88.4%) received standard enoxaparin and 17 (11.6%) received reduced enoxaparin. Overall, 9 bleeding events (7.0%) and 2 major VTE events (1.6%) occurred, all within the standard enoxaparin group. Conclusion: Standard dose enoxaparin for post-operative VTE prophylaxis demonstrated increased bleeding and thrombotic events requiring medical and surgical intervention in comparison to reduced dose enoxaparin for low body weight CORS patients. The results of this study are hypothesis generating and continued research involving more robust systematic reviews are needed to evaluate both safety and efficacy of reduced VTE prophylaxis with LMWH in the underweight, surgical patient population.

Risk of Postoperative Thromboembolism in Men Undergoing Urological Prosthetic Surgery: An Assessment of 21,413 Men.

We assessed venous thromboembolism (VTE) and associated risk factors following artificial urinary sphincter (AUS) and inflatable penile prosthesis (IPP) surgery. Using IBM® MarketScan, a commercial claims database, patients undergoing AUS and IPP surgery were identified using CPT® and ICD (International Classification of Diseases)-10 procedure codes between 2008 and 2017. ICD-9 and -10 codes were used to identify health care visits associated with lower extremity deep vein thrombosis (DVT) and pulmonary embolism (PE) within 90 days of surgery. Covariates were assessed using a multivariable model to determine association with outcome of DVT and/or PE. A total of 21,413 men underwent AUS (4,870) or IPP (16,543) surgery between 2008 and 2017 with a median age of 62 years and 68 years, respectively. DVT and PE events following AUS and IPP surgery occurred in 1.54% and 1.04%, respectively. A history of varicose veins (HR 2.76; 95% CI 1.11-6.79), prior history of DVT (HR 13.65; 95% CI 7.4-25.19), or PE (HR 7.65; 95% CI 4.01-14.6) in those undergoing AUS surgery was highly associated with development of postoperative VTE. Likewise, prior history of DVT (HR 12.6; 95% CI 7.99-19.93) and PE (HR 8.9; 95% CI 5.6-14.13) was strongly associated with a VTE event following IPP surgery. In a large cohort of men undergoing AUS and IPP surgery, 1.54% and 1.04% of men experienced a VTE event within 90 days of surgery, respectively. Prior history of varicose veins, DVT, and PE was associated with an increased likelihood of developing a postoperative DVT or PE.

Abelacimab for Prevention of Venous Thromboembolism

BackgroundThe role of factor XI in the pathogenesis of postoperative venous thromboembolism is uncertain. Abelacimab is a monoclonal antibody that binds to factor XI and locks it in the zymogen (inactive precursor) conformation.MethodsIn this open-label, parallel-group trial, we randomly assigned 412 patients who were undergoing total knee arthroplasty to receive one of three regimens of abelacimab (30 mg, 75 mg, or 150 mg) administered postoperatively in a single intravenous dose or to receive 40 mg of enoxaparin administered subcutaneously once daily. The primary efficacy outcome was venous thromboembolism, detected by mandatory venography of the leg involved in the operation or objective confirmation of symptomatic events. The principal safety outcome was a composite of major or clinically relevant nonmajor bleeding up to 30 days after surgery.ResultsVenous thromboembolism occurred in 13 of 102 patients (13%) in the 30-mg abelacimab group, 5 of 99 patients (5%) in the 75-mg abelacimab group, and 4 of 98 patients (4%) in the 150-mg abelacimab group, as compared with 22 of 101 patients (22%) in the enoxaparin group. The 30-mg abelacimab regimen was noninferior to enoxaparin, and the 75-mg and 150-mg abelacimab regimens were superior to enoxaparin (P<0.001). Bleeding occurred in 2%, 2%, and none of the patients in the 30-mg, 75-mg, and 150-mg abelacimab groups, respectively, and in none of the patients in the enoxaparin group.ConclusionsThis trial showed that factor XI is important for the development of postoperative venous thromboembolism. Factor XI inhibition with a single intravenous dose of abelacimab after total knee arthroplasty was effective for the prevention of venous thromboembolism and was associated with a low risk of bleeding. (Funded by Anthos Therapeutics; ANT-005 TKA EudraCT number, 2019-003756-37.)

P361 No increased postoperative risk of venous thromboembolism in patients with Ulcerative Colitis undergoing colectomy after tofacitinib exposure

Abstract Background Colectomy for ulcerative colitis (UC) has been associated with postoperative morbidity and mortality, including venous thromboembolism (VTE). Patients with inflammatory bowel diseases (IBD) have a 2 to 4-fold increased risk for developing VTE, as compared to non-IBD patients. Due to recent concerns on increased VTE associated with tofacitinib exposure, we aimed to evaluate the 180-day postoperative VTE risk in UC patients undergoing colectomy after tofacitinib use in comparison to patients failing biologicals and undergoing the same surgery. Methods This retrospective cohort study included all UC patients who underwent colectomy between 2014 and 2020 in our tertiary IBD center. All medical charts were reviewed, and clinically relevant information extracted, including indication for colectomy, development of postoperative VTE (deep venous thrombosis, pulmonary or extra-pulmonary embolisms) within 180 days of surgery, low-molecular weight heparin (LMWH) prophylaxis and perioperative therapy exposure (steroids within 1 month prior to surgery, biologicals or tofacitinib within 3 months prior to surgery). Results One-hundred seven UC patients (49.5% women, median [IQR] age 38.0 [27.0 – 53.0] years) underwent colectomy due to refractory disease (n=93), dysplasia or carcinoma (n=12) or polyposis (n=2) (Table 1). Thirty-six (33.6%) patients were operated urgently. At the time of surgery, 44 (41.1%) were on steroids, 38 (35.5%) on anti-TNF agents, 27 (25.2%) on vedolizumab/etrolizumab, 6 (5.6%) on anti-IL12/23 agents and 12 (11.2%) on tofacitinib. All patients received antithrombotic prophylactic LMWH postoperatively. During the 180-day postoperative period, 3 (2.8%) patients developed an intra-abdominal thrombosis, none of them had a history of VTE. Two thromboses were found by coincidence on CT scans which were performed in light of postoperative fever and inflammatory blood tests, the other patient was symptomatic. All 3 patients had been exposed to vedolizumab: one had an underlying malignancy (colon adenocarcinoma), the 2 others also had been exposed to corticosteroids prior to colectomy. No VTE was seen in the patients who underwent colectomy while on tofacitinib. Conclusion The overall risk for UC patients to develop VTE after colectomy is low with adequate antithrombotic prophylactic therapy. In particular, we did not observe any VTE in our colectomy patients who were exposed to tofacitinib prior to surgery. The three patients who developed VTE despite LMWH had additional risk factors (concomitant steroid use, active cancer).

Minimally Invasive Surgery is Associated with an Increased Risk of Postoperative Venous Thromboembolism After Distal Pancreatectomy.

Venous thromboembolism (VTE) is a major cause of morbidity and mortality following distal pancreatectomy (DP). However, the influence of operative technique on VTE risk after DP is unknown. The purpose of this study was to examine the association between the MIS technique versus the open technique and the development of postoperative VTE after DP. Patients who underwent DP from 2014 to 2015 were identified in the American College of Surgeons National Surgical Quality Improvement Program pancreas-specific database. Multivariable logistic regression was then used to identify independent associations with the development of postoperative VTE after DP. A total of 3558 patients underwent DP during this time period. Of these cases, 47.8% (n = 1702) were performed via the MIS approach. After adjusting for significant covariates, the MIS approach was independently associated with the development of any VTE (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.06-2.40; p = 0.025), as well as increasing the risk of developing a postdischarge VTE (OR 1.80, 95% CI 1.05-3.08; p = 0.033) when compared with the open approach. There was an association between VTE and the development of numerous postoperative complications, including pneumonia, unplanned intubation, need for prolonged mechanical ventilation, and cardiac arrest. Compared with the open approach, the MIS approach is associated with higher rates of postoperative VTE in patients undergoing DP. The majority of these events are diagnosed after hospital discharge.

Association of Perioperative Red Blood Cell Transfusions With Venous Thromboembolism in a North American Registry

Increasing evidence supports the role of red blood cells (RBCs) in physiological hemostasis and pathologic thrombosis. Red blood cells are commonly transfused in the perioperative period; however, their association with postoperative thrombotic events remains unclear. To examine the association between perioperative RBC transfusions and postoperative venous thromboembolism (VTE) within 30 days of surgery. This analysis used prospectively collected registry data from the American College of Surgery National Surgical Quality Improvement Program (ACS-NSQIP) database, a validated registry of 525 teaching and nonteaching hospitals in North America. Participants included patients in the ACS-NSQIP registry who underwent a surgical procedure from January 1 through December 31, 2014. Data were analyzed from July 1, 2016, through March 15, 2018. Risk-adjusted odds ratios (aORs) were estimated using multivariable logistic regression. The primary outcome was the development of postoperative VTE (deep venous thrombosis [DVT] and pulmonary embolism [PE]) within 30 days of surgery that warranted therapeutic intervention; DVT and PE were also examined separately as secondary outcomes. Subgroup analyses were performed by surgical subtypes. Propensity score matching was performed for sensitivity analyses. Of 750 937 patients (56.8% women; median age, 58 years; interquartile range, 44-69 years), 47 410 (6.3%) received at least 1 perioperative RBC transfusion. Postoperative VTE occurred in 6309 patients (0.8%) (DVT in 4336 [0.6%]; PE in 2514 [0.3%]; both DVT and PE in 541 [0.1%]). Perioperative RBC transfusion was associated with higher odds of VTE (aOR, 2.1; 95% CI, 2.0-2.3), DVT (aOR, 2.2; 95% CI, 2.1-2.4), and PE (aOR, 1.9; 95% CI, 1.7-2.1), independent of various putative risk factors. A significant dose-response effect was observed with increased odds of VTE as the number of intraoperative and/or postoperative RBC transfusion events increased (aOR, 2.1 [95% CI, 2.0-2.3] for 1 event; 3.1 [95% CI, 1.7-5.7] for 2 events; and 4.5 [95% CI, 1.0-19.4] for ≥3 events vs no intraoperative or postoperative RBC transfusion; P < .001 for trend). In subgroup analyses, the association between any perioperative RBC transfusion and postoperative VTE remained statistically significant across all surgical subspecialties analyzed. The association between any perioperative RBC transfusion and the development of postoperative VTE also remained robust after 1:1 propensity score matching (47 142 matched pairs; matched OR, 1.9; 95% CI, 1.8-2.1). The results of this study suggest that perioperative RBC transfusions may be significantly associated with the development of new or progressive postoperative VTE, independent of several putative confounders. These findings, if validated, should reinforce the importance of rigorous perioperative management of blood transfusion practices.

Incidence and risk factors for venous thromboembolism in bilateral breast reduction surgery: An analysis of the National Surgical Quality Improvement Program

The risk of venous thromboembolism (VTE) in patients undergoing bilateral breast reduction surgery remains unknown. This study aimed to determine VTE incidence and risk factors in this patient cohort. American College of Surgeons National Surgical Quality Improvement Program (2010-2014) was used to identify women undergoing bilateral breast reduction. Demographic factors, comorbidities, and incidence of postoperative VTE were evaluated. Bivariate and risk-adjusted multivariate logistic regressions were performed to determine factors associated with the development of postoperative VTE. A total of 5371 cases were identified. The mean age was 43.7 years (SD±13.9 years). The rate of VTE was 0.22%, with 0.17% rate of pulmonary embolism and 0.07% rate of deep venous thrombosis requiring treatment. Patients who suffered VTE were older (52.4±12.8 vs. 43.7±13.9 years, p<0.05), had longer length of stay (1.7±2.9 vs. 0.4±2.1 days, p<0.05), and had higher rates of blood transfusion (8.3% vs. 0.4%, p<0.01) and reoperation (16.7% vs. 2.0%, p<0.01). Risk-adjusted multivariate analysis demonstrated that older age (OR 1.05, 95% CI 1.01-1.10), postoperative blood transfusion (OR 12.1, 95% CI 1.3-112.0) and unplanned return to the operating room (OR 6.7, 95% CI 1.3-34.8) were independent risk factors for developing postoperative VTE. In bilateral breast reduction surgery, older patients, patients requiring blood transfusion, and patients who have unplanned return to the operating room are at an increased risk of developing postoperative VTE. These factors can be considered for patient risk-stratification and perioperative decision-making regarding VTE prevention.

The dynamics of D-dimer level fluctuation in patients after the cemented and cementless total hip and total knee replacement.

IntroductionThe number of total hip and total knee replacement procedures performed worldwide has tended to surge in recent years, due to the combination of such factors as the increased life expectancy, improved quality of life, advances in medical technology as well as pre-operative and post-operative patient management.Numerous studies confirm that patients undergoing major orthopaedics procedures involving lower extremities, for instance total hip and total knee replacement, constitute the highest risk group for the development of post-operative venous thromboembolism (VTE), primarily manifested as deep vein thrombosis (DVT).PurposeThe purpose of the research was to assess the dynamics of D-dimer level fluctuation during the post-operative period in patients after the cemented or cementless total hip replacement (THR) or total knee replacement (TKR), in order to prove or reject the thesis that the cemented and cementless THR or TKR affects the post-operative D-dimer levels.Material and methodsThe study group consisted of 47 patients aged 29–82 years. Of them, 23 had the cementless THR, 12 subjects had the cemented THR and another 12 patients had the TKR. All of the patients performed to measure the concentration of D-dimers in the peri-operative period at predetermined time points. For the peri-operative period was adopted from time 1 day before surgery to 10-day hospitalization. The subarachnoid block (SAB) was performed in all patients.ResultsThe distribution of D-dimer values throughout the entire post-operative period (up to 10th post-operative day) followed the sinusoid pattern with two peaks in all patients. It was not specific in any group.ConclusionsThe D-dimer level almost doubles during the post-operative period in patients after THR or TKR.Higher level of D-dimers in post-operative period in the research group of patients does not relate to higher risk of thromboembolic disease.

Influence of patient positioning and pneumoperitoneum on lower limbs venous haemodynamics during laparoscopic cholecystectomy

The introduction of laparoscopic surgery has dramatically changed the management of gallstone disease, establishing laparoscopic cholecystectomy as the method of choice for treating cholelithiasis. The aim of this study is to review the significance of patient positioning and pneumoperitoneum in laparoscopic cholecystectomy as potential risk factors for the development of postoperative venous thromboembolism (VTE), with the use of impedance plethysmography (IPG). We studied 40 consecutive patients undergoing selective laparoscopic cholecystectomy. Seventeen patients of our study group were positioned on the operating table in the lithotomy (French) position and 23 in the supine (American) position. Femoral venous capacitance (VC) and maximum venous outflow (MVO) from both legs of the patient was obtained using an impedance ple-thysmography (IPG) device. These parameters were measured: a) the day before operation, b) after French or American positioning on the surgical table, c) at the time of inflation to produce pneumoperitoneum, d) 30 minutes after pneumoperitoneum, and e) 24 hours after surgery. Our study confirms that the patient’s position on the surgical table (French or American position) does not affect venous haemodynamics of the legs. Peritoneal carbon dioxide insufflations to an intrabdominal pressure of 12 mm Hg produce haemodynamic changes, significantly increased after the beginning of peritoneal insufflations.VC and MVO were significantly increased during surgery in both positions. However, after exsufflation and at the first postoperative day, all haemodynamic parameters returned to preoperative values. Our study advocates no difference between French or American positioning during laparoscopic cholecystectomy in measurements obtained from both legs of the patient using an impedance plethysmography device.

Is Development of Postoperative Venous Thromboembolism Related to Thromboprophylaxis Use? A Case-Control Study in the Veterans Health Administration

Observational studies continue to report thromboprophylaxis underuse for postoperative pulmonary embolism/deep vein thrombosis (pPE/DVT) despite the long-standing existence of prevention guidelines. However, data are limited on whether thromboprophylaxis use differs between patients developing pPE/DVT versus those who do not or on why prophylaxis is withheld. Administrative data (2002-2007) from 28 Veterans Health Administration hospitals were screened for discharges with (1) pPE/DVT as flagged by the Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicator software and (2) pharmacoprophylaxis-recommended procedures, and the medical records were reviewed to ascertain true pPE/DVT cases. Controls were selected by matching cases by hospital, age, sex, diagnosis-related group, and predicted probability for developing pPE/DVT, and who underwent a pharmacoprophylaxis-recommended procedure. Records were assessed for "appropriate pharmacoprophylaxis use," defined primarily per American College of Chest Physicians (ACCP) guidelines, and reasons for anticoagulant nonuse. The 116 case-control pairs were similar in terms of demographics, surgery type, ACCP risk category, and appropriate pharmacoprophylaxis rates overall. Of the highest-risk patients, respective pharmacoprophylaxis rates among cases and controls were 88% versus 92% among hip/knee replacements and 31% versus 48% among cancer patients. Of the cases and controls who did not receive appropriate pharmacoprophylaxis, only about 25% had documented contraindications. Reviewers identified contraindications in 14% of cases and 9% of controls. Similarities in preventive pPE/DVT practice between cases and controls suggest that pPE/DVTs occur despite implementation of guideline-adherent practices.

Prophylaxis of Venous Thromboembolism Following Orthopedic Surgery: Mechanical and Pharmacological Approaches and the Need for Extended Prophylaxis

IntroductionMajor orthopedic surgery, particularly total joint replacement or hip fracture, represents a high risk of future development of postoperative venous thromboembolism and warrants the routine use of prophylaxis with either mechanical devices or pharmacological agents. The aim of prophylaxis is to prevent fatal pulmonary embolism (PE) and the morbidity of deep vein thrombosis (DVT), particularly the development of post-thrombotic syndrome. Patterns of clinical practice, with respect to the prevention of venous thromboembolism and the appropriate use of anticoagulants for the treatment of thrombotic disease, have been strongly influenced by recent consensus conferences.1,2 Rules of evidence for assessing the literature have been applied to all recommendations regarding the prevention and treatment of thrombotic disease. These results were extrapolated using evidence gleaned from major clinical disorders and are based only on nonrandomized clinical trials or case series.1-3 Data from a large number of Level I clinical trials in patients undergoing orthopedic surgery have provided answers to many of the questions regarding prophylaxis of venous thromboembolism. In this review, we will discuss the prevention of venous thromboembolism following orthopedic surgery and discuss some of the controversial issues where further studies are required.

Prevention of postoperative venous thromboembolism following laparoscopic cholecystectomy

Advantages of laparoscopic cholecystectomy are less patient discomfort and shorter hospital stay than with the traditional open approach. Nevertheless, this operation is performed under general anesthesia, using muscle relaxants and pneumoperitoneum, with most patients in the reverse Trendelenburg position. It has been shown that this procedure is associated with significant hypercoagulability and dilation of the veins of the leg. We review the role of these factors as potential risk factors for the development of postoperative venous thromboembolism and also report the rate of thromboembolic complications following laparoscopic cholecystectomy. Based on the available evidence, it is concluded that laparoscopic cholecystectomy, despite being a "minimally invasive procedure," may be associated with a definite risk of developing postoperative venous thromboembolism that could extend beyond hospital discharge. Accordingly, thrombosis prophylaxis should be considered for these patients.