Procedure-specific venous thromboembolism prophylaxis: a paradigm from colectomy surgery

Incidence, prevention, risk factors, and prediction of venous thromboembolism in Chinese patients after colorectal cancer surgery: a prospective, multicenter cohort study

BACKGROUND

Venous thromboembolism (VTE) is a common and serious complication after colorectal cancer (CRC) surgery. Few large-sample studies have reported VTE incidence and management status after CRC surgery in China. This study aimed to investigate the incidence and prevention of VTE in Chinese patients after CRC surgery, identify risk factors for developing VTE, and construct a new scoring system for clinical decision-making and care planning.

METHODS

Participants were recruited from 46 centers in 17 provinces in China. Patients were followed up for 1 month postoperatively. The study period was from May 2021 to May 2022. The Caprini score risk stratification and VTE prevention and incidence were recorded. The predictors of the occurrence of VTE after surgery were identified by multivariate logistic regression analysis, and a prediction model (CRC-VTE score) was developed.

RESULTS

A total of 1836 patients were analyzed. The postoperative Caprini scores ranged from 1 to 16 points, with a median of 6 points. Of these, 10.1% were classified as low risk (0-2 points), 7.4% as moderate risk (3-4 points), and 82.5% as high risk (≥5 points). Among these patients, 1210 (65.9%) received pharmacological prophylaxis, and 1061 (57.8%) received mechanical prophylaxis. The incidence of short-term VTE events after CRC surgery was 11.2% (95% CI 9.8-12.7), including deep venous thrombosis (DVT) (11.0%, 95% CI 9.6-12.5) and pulmonary embolism (PE) (0.2%, 95% CI 0-0.5). Multifactorial analysis showed that age (≥70 years), history of varicose veins in the lower extremities, cardiac insufficiency, female sex, preoperative bowel obstruction, preoperative bloody/tarry stool, and anesthesia time at least 180 min were independent risk factors for postoperative VTE. The CRC-VTE model was developed from these seven factors and had good VTE predictive performance ( C -statistic 0.72, 95% CI 0.68-0.76).

CONCLUSIONS

This study provided a national perspective on the incidence and prevention of VTE after CRC surgery in China. The study offers guidance for VTE prevention in patients after CRC surgery. A practical CRC-VTE risk predictive model was proposed.

Intermittent pneumatic compression versus additional prophylaxis with enoxaparin for prevention of venous thromboembolism after laparoscopic surgery for gastric and colorectal malignancies: multicentre randomized clinical trial

Background

The role of antithrombotic chemoprophylaxis in prevention of venous thromboembolism (VTE) in laparoscopic surgery for gastric and colorectal malignancies is unknown. This study compared the addition of enoxaparin following intermittent pneumatic compression (IPC) with IPC alone in patients undergoing laparoscopic surgery for gastrointestinal malignancy.

Methods

In this multicentre RCT, eligible patients were older than 40 years and had a WHO performance status of 0 or 1. Exclusion criteria were prescription of antiplatelet or anticoagulant drugs and history of VTE. Patients were allocated to IPC or to ICP with enoxaparin in a 1 : 1 ratio. Stratification factors included sex, location of cancer, age 61 years and over, and institution. Enoxaparin was administered on days 1–7 after surgery. Primary outcome was VTE, evaluated by multidetector CT on day 7.

Results

Of 448 patients randomized, 208 in the IPC group and 182 in the IPC with enoxaparin group were evaluated. VTE occurred in ten patients (4·8 per cent) in the IPC group and six (3·3 per cent) in the IPC with enoxaparin group (P = 0·453). Proximal deep vein thrombosis and/or pulmonary embolism occurred in seven patients (3·4 per cent) in the IPC group and one patient (0·5 per cent) in the IPC with enoxaparin group (P = 0·050). All VTE events were asymptomatic and non‐fatal. Bleeding occurred in 11 of 202 patients in the IPC with enoxaparin group, and one patient needed a transfusion. All bleeding events were managed by discontinuation of the drug.

Conclusion

IPC with enoxaparin after laparoscopic surgery for gastric and colorectal malignancies did not reduce the rate of VTE. Registration number: UMIN000011667 ( https://www.umin.ac.jp/).

Could Preoperative Unintended Weight Loss Predispose to Postoperative Thrombosis in Patients Undergoing Colorectal Cancer Surgery? An Analysis of the NSQIP Data

Objective: A significant portion of colorectal cancer patients lose weight preoperatively. Here we examine the influence of pre-operative significant weight loss on venous thromboembolism (VTE) risk and determine whether pre-operative BMI and albumin could influence VTE outcomes in patients who have lost significant weight prior to surgery.Methods: We conducted a retrospective cohort study using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) and identified 103,455 colorectal cancer patients undergoing major surgery from 2008 to 2012. Patients were assigned to one of two groups based on whether they lost significant weight preoperatively or not. Simple and stepwise multiple logistic regressions were used to evaluate the association between pre-operative unintended weight loss and 30-days postoperative outcomes. The association between weight loss and postoperative thrombosis was further assessed across several strata.Results: The overall prevalence of pre-operative significant weight loss was 6.8%. Significant weight loss prior to surgery was significantly and independently associated with a higher risk of VTE (adjusted OR 1.23, 95% CI 1.06-1.44), mortality (adjusted OR 1.55, 95% CI 1.35-1.78), composite morbidity (adjusted OR 1.52, 95% CI 1.42-1.62), bleeding (adjusted OR 1.78, 95% CI 1.67-1.91) and return to operation room (adjusted OR 1.29, 95% CI 1.16-1.42). The effect of pre-operative significant weight loss on thromboembolic outcome was evident across patients with a BMI <18.5 kg/m², 18.5 < BMI < 24.99 and BMI >40kg/m².Conclusions: Significant weight loss and BMI both need to be measured preoperatively to stratify patients who are at a higher risk of VTE.

Efficacy and safety of anticoagulant prophylaxis for prevention of postoperative venous thromboembolism in Japanese patients undergoing laparoscopic colorectal cancer surgery

AIM

To investigate the efficacy and safety of anticoagulant prophylaxis to prevent postoperative venous thromboembolism (VTE) during laparoscopic colorectal cancer (CRC) surgery, which is unknown in Japanese patients.

METHODS

We conducted this randomized controlled trial at nine institutions in Japan from 2011 to 2015. It included 302 eligible patients aged 20 years or older who underwent elective laparoscopic surgery for CRC. Patients were randomly assigned to an intermittent pneumatic compression (IPC) therapy group or to an IPC + anticoagulation therapy group. Anticoagulation therapy comprised fondaparinux or enoxaparin for postoperative VTE prophylaxis. Postoperative VTE was diagnosed based on enhanced multi-detector helical computed tomography. The primary endpoint was VTE incidence, including asymptomatic cases, the secondary endpoint was incidence of major bleeding, and we conducted an intention-to-treat analysis. This study is registered in UMINCTR (UMIN000008435).

RESULTS

Postoperative VTE incidence was 5.10% with IPC therapy (n = 157) and 2.76% with IPC + anticoagulant therapy (n = 145; P = .293). We identified no symptomatic VTE cases. The major bleeding rates were 1.27% with IPC alone and 1.38% with the combination (P = .936). The overall bleeding rates were 7.69% for enoxaparin and 13.6% for fondaparinux (P = .500), and there were no bleeding-related deaths.

CONCLUSION

Anticoagulant prophylaxis did not reduce the incidence of VTE and the incidence of major bleeding was comparable between the two groups. Usefulness of perioperative anticoagulation was not demonstrated in this study. Pharmacological prophylaxis must be restricted in Japanese patients with higher risk of VTE.

[Application of standardized venous thromboembolism prevention program in burn patients]

OBJECTIVE

To develop a standardized venous thromboembolism (VTE) prevention program for burn patients and verify its safety and effectiveness by comparing with traditional thrombus prophylaxis.

METHODS

All burn patients admitted and met selection criteria betweem April 2017 and September 2018 were included. Patients between January 2018 and September 2018 were included as the interventional group to implement standardized VTE prevention programs, while patients between April 2017 and December 2017 were included as the control group and traditional active and passive exercises were used to prevent VTE. There was no significant difference in the age, gender, ethnic group, marriage, education, occupation, type and site of the injury, burn area, operation time, and hospital stay between the two groups ( P>0.05), which was comparable. The incidence of VTE, number of cases of tissue or organ hemorrhage, survival rate of skin grafting, and time of wound healing were compared.

RESULTS

The incidence of VTE was obviously lower in the interventional group (1.56%, 1/64) than in the control group (10.17%, 6/59) ( χ 2=-2.05, P=0.04). No bleeding occurred in any tissue or organ in the two groups. The survival rate of skin grafting and the time of wound healing were 89.06% (57/64) and (11.78±3.08) days respectively in the interventional group and 91.53% (54/59) and (11.66±2.30) days respectively in the control group; and the differences between the two groups were not statistically significant ( χ 2=0.21, P=0.65; t=-0.22, P=0.83).

CONCLUSION

The standardized VTE prevention program can effectively prevent the occurrence of VTE, and its safety is relatively high.

Do All Abdominal Neuroendocrine Tumors Require Extended Postoperative VTE Prophylaxis? A NSQIP Analysis

BACKGROUND

Venous thromboembolism (VTE) occurs at high incidence in abdominal cancer surgery; therefore, a 4-week postoperative VTE prophylaxis is advocated. However, most patients with neuroendocrine tumors (NETs) have more favorable prognoses. This study aimed to determine the incidence of VTE in patients with abdominal NETs, compare these rates to other abdominal malignancies, and identify VTE risk factors.

METHODS

The ACS-NSQIP database was queried to identify patients with abdominal NETs and other abdominal malignancies who underwent surgery from 2008 to 2015. A 30-day postoperative VTE incidence for each group was compared. Univariable and multivariable analyses were used to identify VTE risk factors.

RESULTS

Of the 7226 operations for patients with benign (2154) and malignant (5072) abdominal NETs, 144 patients experienced a VTE without significant differences between groups. Subgroup analysis revealed a spectrum of VTE rates. Compared to VTE rates of other abdominal malignancies, patients with benign (1.1% vs. 2.4%, p < 0.001) or malignant (1.7% vs. 2.4%, p < 0.001) non-pancreatic abdominal NETs had significantly lower rates, malignant pancreatic NETs (PNETs) (3.4% vs. 2.4%, p = 0.03) had significantly higher rates, and benign PNETs (3.2% vs. 2.4%, p = 0.21) had comparable rates. Multivariable analysis identified pre-operative albumin (p < 0.001), bleeding disorders (p < 0.001), operative time (p < 0.001), and having a PNET (p = 0.04) as risk factors for VTE in abdominal NET patients.

CONCLUSION

Routine extended VTE prophylaxis after surgery may be necessary in PNETs, but probably unnecessary in other abdominal NETs. However, clinicians should use risk factors identified in this study when considering to forego extended VTE prophylaxis in NET patients.

Venous thromboembolism in colorectal surgery: Incidence, risk factors, and prophylaxis

Colorectal surgery is associated with a high risk of perioperative venous thromboembolism (VTE), and this risk is especially high following colorectal cancer resection and surgery for inflammatory bowel disease. Previous analyses of large databases have reported the incidence of postoperative VTE in this population to be approximately 1.1%-2.5%. Therefore, to minimize this risk, patients should be offered appropriate prophylaxis, which may involve a combination of mechanical and pharmacologic prophylaxis with low-dose unfractionated heparin or low molecular weight heparin as recommended by several guidelines. Prior to initiation of treatment, appropriate risk stratification should be performed according to the patients' basic and disease-related as well as procedure-related risk factors, and post-operative factors. Furthermore, a risk-benefit calculation that takes into account patients' VTE and bleeding risk should be performed prior to starting pharmacologic prophylaxis and to help determine the duration of treatment.

Optimizing Preoperative Anemia to Improve Patient Outcomes

Anemia is a decrease in red blood cell mass, which hinders oxygen delivery to tissues. Preoperative anemia has been shown to be associated with mortality and morbidity following major surgery. The preoperative care clinic is an ideal place to start screening for anemia and discussing potential interventions in order to optimize patients for surgery. This article (1) reviews the relevant literature and highlights consequences of preoperative anemia in the surgical setting, and (2) suggests strategies for screening and optimizing anemia in the preoperative setting.

The inflammatory reflex and neural tourniquet: harnessing the healing power of the vagus nerve

The CNS helps protect against tissue injury. The most important priorities include limiting blood loss and systemic inflammation. We elucidated two endogenous neural pathways that rapidly and specifically improve hemostasis and decrease inflammation through vagus nerve signaling. Activation of the neural tourniquet or inflammatory reflex via electrical vagus nerve stimulation (VNS) significantly improves outcomes in preclinical disease models. Currently, VNS is clinically approved for the treatment of medically refractory epilepsy and depression. The growing field of bioelectronic medicine will help physicians harness the Neural Tourniquet™ and inflammatory reflex for clinical use as well. Considering the substantial harm caused by uncontrolled bleeding and inflammation, electrical VNS may dramatically improve the care of millions of patients.

Incidence of venous thromboembolic events in enhanced recovery after surgery for colon cancer: a retrospective, population-based cohort study

AIM

Both the Danish and the National Institute of Clinical Excellence (NICE) guidelines recommend prolonged thromboprophylaxis (PT) with low-molecular-weight heparin (LMWH) for 28 days postoperatively after elective surgery for colon cancer. The evidence relies on data from two randomized clinical trials (RCTs) that included not only colon cancers but also other abdominal cancers or benign colorectal diseases. Neither of those studies investigated the risk of venous thromboembolism (VTE) under enhanced recovery after surgery (ERAS). We aim to describe the risk of VTE and estimate the cost of preventing one case of VTE by PT under ERAS.

METHOD

This was a retrospective study of 2230 patients undergoing elective surgery for colon cancer Stage I-III in the Capital Region of Denmark, 1 June 2008 to 31 December 2013. Patients who were discharged on postoperative day 28 or later, died during admission or were discharged with a vitamin K antagonist, novel oral anticoagulants or LMWH were excluded. Patients with rectal cancer only were not included. End-points were symptomatic VTE diagnosed within 60 days postoperatively.

RESULTS

Three-hundred and thirty patients were excluded. For the remaining 1893, the median length of stay (LOS) was 4 [interquartile range (IQR): 3-5] days. Of these 1893 patients, four (0.20%) experienced a nonfatal symptomatic VTE. All four patients had other postoperative complications before the VTE. The cost of each symptomatic VTE prevented is estimated to be between £63 709 and £111 455 when medication and home-care nursing are included.

CONCLUSION

The risk of symptomatic VTE after uncomplicated, elective surgery for colon cancer with ERAS seems negligible and the cost-effectiveness of PT to prevent one symptomatic VTE seems questionable.

Individualized Venous Thromboembolism Risk Stratification Using the 2005 Caprini Score to Identify the Benefits and Harms of Chemoprophylaxis in Surgical Patients: A Meta-analysis

OBJECTIVE

We performed a meta-analysis to investigate benefits and harms of chemoprophylaxis among surgical patients individually risk stratified for venous thromboembolism (VTE) using Caprini scores.

SUMMARY OF BACKGROUND DATA

Individualized VTE risk stratification may identify high risk surgical patients who benefit from peri-operative chemoprophylaxis.

METHODS

MEDLINE, EMBASE, and the Cochrane Library (CENTRAL) databases were queried. Eligible studies contained data on postoperative VTE and/or bleeding events with and without chemoprophylaxis. Primary outcomes included rates of VTE and clinically relevant bleeding after surgical procedures, stratified by Caprini score. A meta-analysis was conducted using a random-effects model.

RESULTS

Among 13 included studies, 11 (n = 14,776) contained data for VTE events and 8 (n = 7590) contained data for clinically relevant bleeding with and without chemoprophylaxis. The majority of patients received mechanical prophylaxis. A 14-fold variation in VTE risk (from 0.7% to 10.7%) was identified among surgical patients who did not receive chemoprophylaxis, and patients at increased levels of Caprini risk were significantly more likely to have VTE. Patients with Caprini scores of 7 to 8 [odds ratio (OR) 0.60, 95% confidence interval (95% CI) 0.37-0.97] and >8 (OR 0.41, 95% CI 0.26-0.65) had significant VTE risk reduction after surgery with chemoprophylaxis. Patients with Caprini scores ≤6 comprised 75% of the overall population, and these patients did not have a significant VTE risk reduction with chemoprophylaxis. No association between postoperative bleeding risk and Caprini score was identified.

CONCLUSIONS

The benefit of peri-operative VTE chemoprophylaxis was only found among surgical patients with Caprini scores ≥7. Precision medicine using individualized VTE risk stratification helps ensure that chemoprophylaxis is used only in appropriate surgical patients and may minimize bleeding complications.

The Efficacy of Dextran-40 as a Venous Thromboembolism Prophylaxis Strategy in Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

The incidence of venous thromboembolism (VTE) in peritoneal malignancies can approach 30 to 50 per cent without prophylaxis. Prophylaxis in cytoreductive surgeries (CRS) presents a challenge to preoperative heparin-based therapy because of an increased risk of coagulopathy and potential for bleeding. Herein, we report the large series of CRS and hyperthermic intraperitoneal chemotherapy receiving dextran-40 prophylaxis. Retrospective chart review of peritoneal malignancies patients undergoing CRS at University of Nebraska Medical Center identified 69 individuals who received dextran-40 between 2010 and 2013. The incidences of VTEs, perioperative bleeding, complications, morbidity, and mortality were determined in-hospital and at 90 days. Of the 69 patients treated, the 30-day VTE rate was 8.7 per cent, and no pulmonary embolisms, bleeding, anaphylactoid reaction, or mortality were observed with dextran usage. The specific VTE events included three upper extremity and three lower extremity VTEs. No additional VTE events were identified between 30 and 90 days. In conclusion, dextran-40 prophylaxis was not associated with any perioperative bleeding events, and the observed incidence of VTE was comparable to reported heparin-based prophylaxis in CRS/hyperthermic intraperitoneal chemotherapy patients. This data supports further exploration of dextran-40 as a VTE prophylactic agent in complex surgical oncology cases.

Thromboembolic Complications and Prophylaxis Patterns in Colorectal Surgery

IMPORTANCE

Venous thromboembolism (VTE) is an important complication of colorectal surgery, but its incidence is unclear in the era of VTE prophylaxis.

OBJECTIVE

To describe the incidence of and risk factors associated with thromboembolic complications and contemporary VTE prophylaxis patterns following colorectal surgery.

DESIGN, SETTING, AND PARTICIPANTS

Prospective data from the Washington State Surgical Care and Outcomes Assessment Program (SCOAP) linked to a statewide hospital discharge database. At 52 Washington State SCOAP hospitals, participants included consecutive patients undergoing colorectal surgery between January 1, 2006, and December 31, 2011.

MAIN OUTCOMES AND MEASURES

Venous thromboembolism complications in-hospital and up to 90 days after surgery.

RESULTS

Among 16,120 patients (mean age, 61.4 years; 54.5% female), the use of perioperative and in-hospital VTE chemoprophylaxis increased significantly from 31.6% to 86.4% and from 59.6% to 91.4%, respectively, by 2011 (P < .001 for trend for both). Overall, 10.6% (1399 of 13,230) were discharged on a chemoprophylaxis regimen. The incidence of VTE was 2.2% (360 of 16,120). Patients undergoing abdominal operations had higher rates of 90-day VTE compared with patients having pelvic operations (2.5% [246 of 9702] vs 1.8% [114 of 6413], P = .001). Those having an operation for cancer had a similar incidence of 90-day VTE compared with those having an operation for nonmalignant processes (2.1% [128 of 6213] vs 2.3% [232 of 9902], P = .24). On adjusted analysis, older age, nonelective surgery, history of VTE, and operations for inflammatory disease were associated with increased risk of 90-day VTE (P < .05 for all). There was no significant decrease in VTE over time.

CONCLUSIONS AND RELEVANCE

Venous thromboembolism rates are low and largely unchanged despite increases in perioperative and postoperative prophylaxis. These data should be considered in developing future guidelines.

Development of Team Action Projects in Surgery (TAPS): a multilevel team-based approach to teaching quality improvement

OBJECTIVES

To meet the Accreditation Council for Graduate Medical Education core competency in Practice-Based Learning and Improvement, educational curricula need to address training in quality improvement (QI). We sought to establish a program to train residents in the principles of QI and to provide practical experiences in developing and implementing improvement projects.

DESIGN

We present a novel approach for engaging students, residents, and faculty in QI efforts-Team Action Projects in Surgery (TAPS).

SETTING

Large academic medical center and health system.

PARTICIPANTS

Multiple teams consisting of undergraduate students, medical students, surgery residents, and surgery faculty were assembled and QI projects developed. Using "managing to learn" Lean principles, these multilevel groups approached each project with robust data collection, development of an A3, and implementation of QI activities.

RESULTS

A total of 5 resident led QI projects were developed during the TAPS pilot phase. These included a living kidney donor enhanced recovery protocol, consult improvement process, venous thromboembolism prophylaxis optimization, Clostridium difficile treatment standardization, and understanding variation in operative duration of laparoscopic cholecystectomy. Qualitative and quantitative assessment showed significant value for both the learner and stakeholders of QI related projects.

CONCLUSION

Through the development of TAPS, we demonstrate a novel approach to addressing the increasing focus on QI within graduate medical education. Efforts to expand this multilevel team based approach would have value for teachers and learners alike.

A validated risk model to predict 90-day VTE events in postsurgical patients

BACKGROUND

VTE is the proximate cause of 100,000 deaths in the United States each year. Perioperative VTE risk among surgical patients varies by 20-fold, which highlights the importance of risk stratification to identify high-risk patients, in whom chemoprophylaxis can decrease VTE risk, and low-risk patients, for whom the risk-benefit relationship of prophylaxis may be unfavorable.

METHODS

We used data from a statewide surgical quality collaborative for surgical procedures performed between 2010 and 2012. Regression-based techniques identified predictors of 90-day VTE while adjusting for procedural complexity and comorbid conditions. A weighted risk index was created and was validated subsequently in a separate, independent dataset.

RESULTS

Data were available for 10,344 patients, who were allocated randomly to a derivation or validation cohort. The 90-day VTE rate was 1.4%; 66.2% of the derivation cohort and 65.5% of the validation cohort received chemoprophylaxis. Seven risk factors were incorporated into a weighted risk index: personal history of VTE, current cancer, sepsis/septic shock/systemic inflammatory response syndrome, age≥60 years, BMI≥40 kg/m2, male sex, and family history of VTE. Prediction for 90-day VTE was similar in the derivation and validation cohorts (areas under the receiver operator curve, 0.72 and 0.70, respectively). An 18-fold variation in 90-day VTE rate was identified.

CONCLUSIONS

A weighted risk index quantifies 90-day VTE risk among surgical patients and identifies an 18-fold variation in VTE risk among the overall surgical population.