Mechanical prophylaxis for venous thromboembolism prevention in obese individuals

Effects of elevated body mass index on the success of total knee and total hip arthroplasty: a comprehensive overview

INTRODUCTION

The average body mass index (BMI) in the United States has tripled over the last five decades despite concerted population-based efforts for weight management. Elevated BMI and, in particular, obesity are risk factors for osteoarthritis. This trend has led to increased demands for total knee (TKA) and total hip arthroplasty (THA), necessitating an in-depth understanding of how elevated BMI impacts TKA and THA.

AREAS COVERED

This paper reviews the literature investigating the effects of elevated BMI, primarily obesity, on TKA and THA, focusing on preoperative, intraoperative, and postoperative considerations. It describes the associated risks, economic implications, and ethical considerations of patients with high BMIs undergoing TKA or THA. To ensure all relevant literature was included, Ovid Medline and Google Scholar databases were searched for the following terms, 'body mass index,' 'obesity,' 'knee,' 'hip,' and 'arthroplasty' for articles published from January 2019 through July 2024.

EXPERT OPINION

Despite the challenges of high BMI in TKA and THA, a deeper understanding of obesity as a chronic illness, coupled with advances in surgical techniques, can improve patient outcomes. A multidisciplinary approach and further research will optimize the care of patients with elevated BMIs undergoing total joint arthroplasty (TJA).

The Effect of Intermittent Pneumatic Compression on Hemodynamics and Regional Cerebral Oxygen Saturation in Laparoscopic Bariatric Surgery with Mild Hypercapnia in the Steep Reverse Trendelenburg Position

Obesity negatively affects hemodynamics and cerebral physiology. We investigated the effect of the utilization of an intermittent pneumatic compression (IPC) device on hemodynamics and cerebral physiology in patients undergoing laparoscopic bariatric surgery under general anesthesia with lung-protective ventilation. Sixty-four patients (body mass index > 30 kg/m2) were randomly assigned to groups that received an IPC device (IPC group, n = 32) and did not (control group, n = 32). The mean arterial pressure (MAP), heart rate (HR), need for vasopressors, cerebral oxygen saturation (rSO2), and cerebral desaturation events were recorded. The incidence of intraoperative hypotension was not significantly different between groups (p = 0.153). Changes in MAP and HR over time were similar between groups (p = 0.196 and p = 0.705, respectively). The incidence of intraoperative cerebral desaturation was not significantly different between groups (p = 0.488). Changes in rSO2 over time were similar between the two groups (p = 0.190) during pneumoperitoneum. Applying IPC to patients with obesity in the steep reverse Trendelenburg position may not improve hemodynamic parameters, vasopressor requirements, or rSO2 values during pneumoperitoneum under lung-protective ventilation. During laparoscopic bariatric surgery, IPC alone has limitations in improving hemodynamics and cerebral physiology.

Go Big or Go Home: Obesity and Total Joint Arthroplasty

Obesity is highly prevalent, and it is expected to grow considerably in the United States. The association between obesity and an increased risk of complications following total joint arthroplasty (TJA) is widely accepted. Many believe that patients with body mass index (BMI) >40 have complications rates that may outweigh the benefits of surgery and should consider delaying it. However, the current literature on obesity and outcomes following TJA is observational, very heterogeneous, and full of confounding variables. BMI in isolation has several flaws and recent literature suggests shifting from an exclusively BMI <40 cutoff to considering 5 to 10% preoperative weight loss. BMI cutoffs to TJA may also restrict access to care to our most vulnerable, marginalized populations. Moreover, only roughly 20% of patients instructed to lose weight for surgery are successful and the practice of demanding mandatory weight loss needs to be reconsidered until convincing evidence exists that supports risk reduction as a result of preoperative weight loss. Obese patients can benefit greatly from this life-changing procedure. When addressing the potential difficulties and by optimizing preoperative assessment and intraoperative management, the surgery can be conducted safely. A multidisciplinary patient-centered approach with patient engagement, shared decision-making, and informed consent is recommended.

Method of venous thromboembolism prophylaxis is not a predictor of pulmonary embolus following elective bariatric surgery: a retrospective cohort study of 135,409 patients

BACKGROUND

Patients with obesity are at increased risk of pulmonary embolus (PE), a risk that increases perioperatively and is challenging to manage.

OBJECTIVE

An analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database was performed to determine predictors of PE in patients undergoing elective bariatric surgery.

SETTING

North American accredited bariatric surgery institutions included in the MBSAQIP database from 2020-2021.

METHODS

We extracted data from the MBSAQIP database (2020-2021) on patients who underwent elective Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). Data were extracted on patient co-morbidities, race, prior history of deep vein thrombosis (DVT), and type of DVT prophylaxis. A multivariate logistic regression model was developed to determine predictors of PE and impact of PE on 30-day serious complications and mortality.

RESULTS

In the MBSAQIP database, a total of 135,409 patients underwent SG or RYGB from 2020 to 2021. PE was reported in 194 patients (.14%). Prior history of DVT (odds ratio [OR] = 3.28; 95% confidence interval [CI]: 1.85-5.83; P < .0001), Black race (OR = 3.03; 95% CI: 2.22-4.13; P < .0001), gastroesophageal reflux disease (OR = 1.51; 95% CI: 1.11-2.04; P = .008), higher body mass index (OR = 1.11; 95% CI: 1.01-1.20; P = .023), male sex (OR = 1.76; 95% CI: 1.26-2.45; P = .001), and older age (OR = 1.27; 95% CI: 1.10-1.46; P = .001) were associated with increased odds of PE. Chronic obstructive pulmonary disease, sleep apnea, and hypertension were not significant predictors of PE (P > .05). Neither combined mechanical and pharmacologic DVT prophylaxis nor pharmacologic prophylaxis alone was a significant predictor of PE (P > .05).

CONCLUSION

Prior history of DVT is the strongest predictor of PE after bariatric surgery. African American race, male sex, and gastroesophageal reflux disease are additional risk factors. Method of venous thromboembolism prophylaxis was not identified as significant predictor of PE. Further, studies on the evaluation and optimization of venous thromboembolism prophylaxis are required.

Obesity and the Risk of Venous Thromboembolism after Major Lower Limb Orthopaedic Surgery: A Literature Review

The risk of venous thromboembolism following total joint arthroplasty is significantly greater than those of other types of elective orthopaedic procedures. This risk is increased in obesity due to the associated prothrombotic physiological and hematological changes that predispose to embolic events. The prevalence of obesity is increasing in the aging population, which contributes to a further increase in the risk of postoperative thrombosis in the older patients. There is a lack of clear evidence regarding dosing information for thromboprophylaxis medications in patients with obesity. As a result, the currently available thromboprophylaxis guidelines do not provide specific recommendations for this group. Suboptimal dosing regimens for these medications can place these patients at a risk of bleeding or clotting complications postsurgery. Hence any increase in dosage may require intensive surveillance for the residual anticoagulant effects and careful balancing of risks and benefits on an individual basis. Our review discusses the basis for increased thrombotic risk in obesity, the evidence supporting dosage recommendations, and the implications of the current guidelines for pharmacological thromboprophylaxis in patients with obesity undergoing lower limb arthroplasty.

Prevalence of Venous Thromboembolism in Intensive Care Units: A Meta-Analysis

OBJECTIVE

Venous thromboembolism (VTE) is a life threating complication in intensive care units (ICUs). This study aimed to pool the prevalence of VTE and examined the risk factors of VTE in intensive care patients worldwide.

METHODS

A systematic search in PubMed, EMBASE and Web of Science databases was performed. Studies reported that the data on the prevalence of VTE or relevant information were synthesized using a random-effects model.

RESULTS

A total of 42 studies reporting on 27,344 patients were included. The pooled prevalence of VTE was 10.0% (95% CI: 7.0-14.0%). Subgroup and metaregression analyses found that thromboprophylaxis strategy, simplified acute physiology score (SAPS II), age, study quality, sample size, malignancy, sex, spinal cord injury and injury severity score (ISS) moderated the prevalence of VTE in intensive care patients.

CONCLUSIONS

The present meta-analysis revealed a high prevalence of VTE in critically ill patients. The risk factors of VTE included thromboprophylaxis strategy, SAPS II, age, malignancy, sex, spinal cord injury and ISS. Therefore, we need to pay more attention to high-risk populations of VTE in intensive care patients.

A Review of Current and Future Antithrombotic Strategies in Surgical Patients-Leaving the Graduated Compression Stockings Behind?

Venous thromboembolism (VTE) remains an important consideration within surgery, with recent evidence looking to refine clinical guidance. This review provides a contemporary update of existing clinical evidence for antithrombotic regimens for surgical patients, providing future directions for prophylaxis regimens and research. For moderate to high VTE risk patients, existing evidence supports the use of heparins for prophylaxis. Direct oral anticoagulants (DOACs) have been validated within orthopaedic surgery, although there remain few completed randomised controlled trials in other surgical specialties. Recent trials have also cast doubt on the efficacy of mechanical prophylaxis, especially when adjuvant to pharmacological prophylaxis. Despite the ongoing uncertainty in higher VTE risk patients, there remains a lack of evidence for mechanical prophylaxis in low VTE risk patients, with a recent systematic search failing to identify high-quality evidence. Future research on rigorously developed and validated risk assessment models will allow the better stratification of patients for clinical and academic use. Mechanical prophylaxis' role in modern practice remains uncertain, requiring high-quality trials to investigate select populations in which it may hold benefit and to explore whether intermittent pneumatic compression is more effective. The validation of DOACs and aspirin in wider specialties may permit pharmacological thromboprophylactic regimens that are easier to administer.