Evidence of thromboembolism prophylaxis in bariatric surgery-results of a quality assurance trial in bariatric surgery in Germany from 2005 to 2007 and review of the literature

Don't Fear the Bleed: Assessing Postoperative Bleeding Incidence After Instituting a Standardized Prophylactic Heparin Protocol in Bariatric Patients

Background: Bariatric surgery is a frequently performed procedure in the United States, accounting for ∼40,000 procedures annually. Patients undergoing bariatric surgery are at high risk for postoperative thrombosis, with a venous thromboembolism (VTE) rate of up to 6.4%. Despite this risk, there is a lack of guidelines recommending postoperative VTE prophylaxis and it is not routine practice at most hospitals. The postoperative bleeding rate after bariatric surgery is only 1.5%; however, the risk of bleeding may lead to hesitancy for more liberal VTE prophylaxis. Methods: This is a retrospective analysis of bariatric surgeries at a single institution in 2019 and 2021. Data were obtained from the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) and electronic medical record review for all patients undergoing sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), or conversion to RYGB. The primary outcomes were composite bleeding events, which included postoperative transfusion, postoperative endoscopy or return to operating room (OR) (for bleeding), intra-abdominal hematoma, gastrointestinal (GI) bleeding, or incisional hematoma. Results: There were a total of 2067 patients in the cohort, with 1043 surgeries in 2019 and 1024 surgeries in 2021. There was no difference between bleeding events after instituting a deep venous thrombosis (DVT) prophylaxis protocol in 2021 (27 versus 28 events, P = .76). There was no difference in individual bleeding events between 2019 and 2021. Additionally, there was no significant difference in the rate of VTE between 2019 and 2021 (2 versus 5 events, P = .28). Conclusions: After instituting a standard protocol of prophylactic heparin postdischarge, we did not find an increased rate of bleeding events in patients undergoing bariatric surgery. Thus, surgeons can consider prescribing postdischarge chemical VTE prophylaxis without concern for bleeding.

Ensuring Safety While Achieving Beauty: An Evidence-Based Approach to Optimizing Mastectomy and Autologous Breast Reconstruction Outcomes in Patients with Obesity

BACKGROUND

Although obesity has previously been associated with poor outcomes after mastectomy and breast reconstruction, its impact across the WHO obesity classification spectrum and the differential effects of various optimization strategies on patient outcomes have yet to be delineated. We sought to examine the impact of WHO obesity classification on intraoperative surgical and medical complications, postoperative surgical and patient-reported outcomes of mastectomy and autologous breast reconstruction, and delineate outcomes optimization strategies for obese patients.

STUDY DESIGN

This is a review of consecutive patients who underwent mastectomy and autologous breast reconstruction from 2016 to 2022. Primary outcomes were complication rates. Secondary outcomes were patient-reported outcomes and optimal management strategies.

RESULTS

We identified 1,640 mastectomies and reconstructions in 1,240 patients with mean follow-up of 24.2 ± 19.2 months. Patients with class II/III obesity had higher adjusted risk of wound dehiscence (odds ratio [OR] 3.20; p < 0.001), skin flap necrosis (OR 2.60; p < 0.001), deep venous thrombosis (OR 3.90; p < 0.033), and pulmonary embolism (OR 15.3; p = 0.001) than nonobese patients. Obese patients demonstrated significantly lower satisfaction with breasts (67.3 ± 27.7 vs 73.7 ± 24.0; p = 0.043) and psychological well-being (72.4 ± 27.0 vs 82.0 ± 20.8; p = 0.001) than nonobese patients. Unilateral delayed reconstructions were associated with independently shorter hospital stay (β -0.65; p = 0.002) and lower adjusted risk of 30-day readmission (OR 0.45; p = 0.031), skin flap necrosis (OR 0.14; p = 0.031), and pulmonary embolism (OR 0.07; p = 0.021).

CONCLUSIONS

Obese women should be closely monitored for adverse events and lower quality of life, offered measures to optimize thromboembolic prophylaxis, and advised on the risks and benefits of unilateral delayed reconstruction.

The Effect of Obesity on Anti-Xa Concentrations in Bariatric Patients

BACKGROUND

Morbidly obese patients are at increased risk to develop venous thromboembolism (VTE), especially after bariatric surgery. Adequate postoperative thrombosis prophylaxis is of utmost importance. It is assumed that morbidly obese patients need higher doses of low molecular weight heparin (LMWH) compared to normal-weight patients; however, current guidelines based on relative efficacy in obese populations are lacking.

OBJECTIVES

First, we will evaluate the relationship between body weight descriptors and anti-Xa activity prospectively. Second, we will determine the dose-linearity of LMWH in morbidly obese patients.

SETTING

This study was performed in a general hospital specialized in bariatric surgery.

METHODS

Patients were scheduled for a Roux-en-Y gastric bypass with a total bodyweight (TBW) of ≥ 140 kg. Patients (n = 50, 64% female) received a daily postoperative dose of 5700 IU of nadroparin for 4 weeks. Anti-Xa activity was determined 4 h after the last nadroparin administration. To determine the dose linearity, anti-Xa was determined following a preoperative dose of 2850 IU nadroparin in another 50 patients (52%).

RESULTS

TBW of the complete group was 148.5 ± 12.6 kg. Mean anti-Xa activity following 5700 IU nadroparin was 0.19 ± 0.07 IU/mL. Of all patients, 32% had anti-Xa levels below the prophylactic range. Anti-Xa activity inversely correlated with TBW (correlation coefficient - 0.410) and lean body weight (LBW; correlation coefficient - 0.447); 67% of patients with a LBW ≥ 80 kg had insufficient anti-Xa activity concentrations. No VTE events occurred.

CONCLUSIONS

In morbidly obese patients, a postoperative dose of 5700 IU of nadroparin resulted in subprophylactic exposure in a significant proportion of patients. Especially in patients with LBW ≥ 80 kg, a higher dose may potentially be required to reach adequate prophylactic anti-Xa levels.

Perioperative management of bariatric surgery patients

PURPOSE

The perioperative management of bariatric surgery patients is described.

SUMMARY

Obesity and anatomical changes create unique challenges for clinicians when caring for bariatric surgery patients. Common bariatric surgery procedures performed include Roux-en-Y gastric bypass, sleeve gastrectomy, and adjustable gastric banding. Pain management in the acute postoperative period depends on careful dosing of opioid agents and the use of adjunctive agents. Prevention and management of infectious complications include appropriate surgical prophylaxis, monitoring and rapid treatment of suspected intra-abdominal infections, and detection and treatment of Helicobacter pylori infection. Venous thromboembolism (VTE) prophylaxis and treatment are complicated by obesity, and the use of pharmacologic agents must be balanced with bleeding risk. Bleeding is a serious complication that should be closely monitored in the immediate postoperative period. Blood products remain first-line therapy for the treatment of bleeding in this population. Acute differences in drug absorption as well as emerging hormonal changes necessitate the immediate postoperative adjustment of chronic medications to ensure both safety and efficacy. Pharmacists are valuable members of interprofessional teams for bariatric surgery patients because they provide expertise on the availability of dosage forms and dosage modification to ensure that patient pharmacotherapy is not interrupted; assist in the management of hypertension, diabetes, and psychotropic medications; and ensure appropriate antimicrobial prophylaxis and VTE prophylaxis and treatment dosages.

CONCLUSION

The management of patients in the perioperative period of bariatric surgery requires appropriate selection and dosing of medications for pain management and treatment of infectious complications, VTE, bleeding, and other chronic diseases.

Prophylaxis of venous thromboembolism with low molecular weight heparin in bariatric surgery: a prospective, randomised pilot study evaluating two doses of parnaparin (BAFLUX Study)

Background

The optimal dose of low molecular weight heparin (LMWH) to prevent venous thromboembolism (VTE) after bariatric surgery remains controversial. The aim of this multicentre, open-label, pilot study was to evaluate the efficacy and safety of two different doses of the LMWH parnaparin administered to patients undergoing bariatric surgery.

Methods

Patients were randomised to receive 4,250 IU/day (group A) or 6,400 IU/day (group B) of parnaparin s.c. for 7–11 days. Bilateral colour Doppler ultrasound of the lower limb was performed before surgery and at the end of the treatment period. The primary efficacy outcome was a composite of asymptomatic and symptomatic deep vein thrombosis, symptomatic pulmonary embolism and death from any cause during treatment. The primary safety endpoint was major and clinically relevant non-major bleeding.

Results

A total of 258 patients underwent randomization; 8 subjects were excluded following the safety analysis. One hundred thirty-one patients [106 females; mean age, 40.3 years (standard deviation (SD) ±9.6); mean body mass index (BMI), 44.6 kg/m² (SD ±5.4)] were assigned to group A and 119 patients [93 females; mean age, 41.5 years (SD ±9.9); mean BMI, 44.2 kg/m² (SD ±5.4)] were assigned to group B. The rate of the primary efficacy outcome was 1.5 % (two cases; 95 % confidence interval (CI), 0.2–6.0 %) in group A as compared with 0.8 % (one case; 95 % CI, 0.4–5.3 %) in group B (p = ns). The composite incidence of major bleeding and clinically relevant non-major bleeding was 6.1 % (eight cases; 95 % CI, 2.9–12.1 %) in group A and 5.0 % (six cases; 95 % CI, 2.1–11.1 %) in group B (p = ns).

Conclusions

A parnaparin dose of 4,250 IU/day seems suitable for VTE prevention in patients undergoing bariatric surgery.

Incidence of deep vein thrombosis and thrombosis of the portal-mesenteric axis after laparoscopic sleeve gastrectomy

BACKGROUND

Venous thromboembolism is the most common postoperative medical complication after bariatric surgery. Mortality associated with thromboembolic processes can reach up to 50%-75%. The aim of this study was to determine the incidence of deep vein thrombosis (DVT) and portal-splenic-mesenteric vein thrombosis (PSMVT) in our population undergoing laparoscopic sleeve gastrectomy (LSG) as the bariatric technique, with an anti-thromboembolic dosage scheme of 0.5 mg/kg/day 12 hours preoperatively and maintained during 30 days postoperatively.

PATIENTS AND METHODS

A prospective observational study was performed, including 100 consecutive patients undergoing LSG between October 2007 and September 2013. To determine the incidence of DVT and PSMVT, all patients undergo contrast-enhanced abdominal computed tomography (CT) and Doppler ultrasonography (US) of both lower limbs on the third postoperative month, whether they were asymptomatic or symptomatic.

RESULTS

Contrast-enhanced CT showed 1 case of PSMVT (1%). Two patients presented DVT in the right leg (2%). All the cases were asymptomatic.

CONCLUSIONS

The incidence of PSMVT and DVT after LSG with a prophylactic low-molecular-weight heparin dose of 0.5 mg/kg/day and maintained during 30 days postoperatively is 1% and 2%, respectively. According to these results, a postoperative screening with Doppler US and/or contrast-enhanced CT seems to be unnecessary.

Deep venous thrombosis in lap band surgery: a single center study

Bariatric surgery has been demonstrated to be an effective treatment for morbid obesity. The purpose of this study is to investigate the incidence of pre- and post-operative deep venous thrombosis (DVT) in Lap-Band surgical patients. This study group comprised 56 consecutive patients who underwent Lap-Band surgery. Mean age and body mass index were 38 years (range: 18-64 years) and 50.9 kg/m(2) (range: 53-74 kg/m(2)), respectively. All the patients were screened with duplex ultrasonography pre- and post-operatively. There were no iliac, femoral, or popliteal vein thromboses detected at any given point of time. No patient had any clinical signs or symptoms of DVT post-operatively. There were no observable differences attributable to DVT prophylaxis. This data suggest that in the setting of chemical and mechanical prophylaxis, the incidence of DVT in patients undergoing Lap-Band surgery at an established bariatric centre is minimal.

Actual situation of thromboembolic prophylaxis in obesity surgery: data of quality assurance in bariatric surgery in Germany

Background. Evidence-based data on optimal approach for prophylaxis of deep venous thrombosis (VTE) and pulmonary embolism (PE) in bariatric operations is discussed. Using antithrombotic prophylaxis weight adjusted the risk of VTE and its complications have to be balanced with the increased bleeding risk. Methods. Since 2005 the current situation for bariatric surgery has been examined by quality assurance study in Germany. As a prospective multicenter observational study, data on the type, regimen, and time course of VTE prophylaxis were documented. The incidences of clinically diagnosed VTE or PE were derived during the in-hospital course and follow up. Results. Overall, 11,835 bariatric procedures were performed between January 2005 and December 2010. Most performed procedures were 2730 gastric banding (GB); 4901 Roux-en-Y-gastric bypass (RYGBP) procedures, and 3026 sleeve gastrectomies (SG). Study collective includes 72.5% (mean BMI 48.1 kg/m(2)) female and 27.5% (mean BMI 50.5 kg/m(2)) male patients. Incidence of VTE was 0.06% and of PE 0.08%. Conclusion. VTE prophylaxis regimen depends on BMI and the type of procedure. Despite the low incidence of VTE and PE there is a lack of evidence. Therefore, prospective randomized studies are necessary to determine the optimal VTE prophylaxis for bariatric surgical patients.

Prevention of VTE in nonorthopedic surgical patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

VTE is a common cause of preventable death in surgical patients.

METHODS

We developed recommendations for thromboprophylaxis in nonorthopedic surgical patients by using systematic methods as described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines. Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.

RESULTS

We describe several alternatives for stratifying the risk of VTE in general and abdominal-pelvic surgical patients. When the risk for VTE is very low (< 0.5%), we recommend that no specific pharmacologic (Grade 1B) or mechanical (Grade 2C) prophylaxis be used other than early ambulation. For patients at low risk for VTE (∼1.5%), we suggest mechanical prophylaxis, preferably with intermittent pneumatic compression (IPC), over no prophylaxis (Grade 2C). For patients at moderate risk for VTE (∼3%) who are not at high risk for major bleeding complications, we suggest low-molecular-weight heparin (LMWH) (Grade 2B), low-dose unfractionated heparin (Grade 2B), or mechanical prophylaxis with IPC (Grade 2C) over no prophylaxis. For patients at high risk for VTE (∼6%) who are not at high risk for major bleeding complications, we recommend pharmacologic prophylaxis with LMWH (Grade 1B) or low-dose unfractionated heparin (Grade 1B) over no prophylaxis. In these patients, we suggest adding mechanical prophylaxis with elastic stockings or IPC to pharmacologic prophylaxis (Grade 2C). For patients at high risk for VTE undergoing abdominal or pelvic surgery for cancer, we recommend extended-duration, postoperative, pharmacologic prophylaxis (4 weeks) with LMWH over limited-duration prophylaxis (Grade 1B). For patients at moderate to high risk for VTE who are at high risk for major bleeding complications or those in whom the consequences of bleeding are believed to be particularly severe, we suggest use of mechanical prophylaxis, preferably with IPC, over no prophylaxis until the risk of bleeding diminishes and pharmacologic prophylaxis may be initiated (Grade 2C). For patients in all risk groups, we suggest that an inferior vena cava filter not be used for primary VTE prevention (Grade 2C) and that surveillance with venous compression ultrasonography should not be performed (Grade 2C). We developed similar recommendations for other nonorthopedic surgical populations.

CONCLUSIONS

Optimal thromboprophylaxis in nonorthopedic surgical patients will consider the risks of VTE and bleeding complications as well as the values and preferences of individual patients.

Management of the metabolic/bariatric surgery patient

There is currently a global pandemic of obesity and obesity-engendered comorbidities; in particular, certain major chronic metabolic diseases (eg, type 2 diabetes) which markedly reduce life expectancy and quality of life. This review is predicated on the fact that management of the obese patient is a primary concern of all physicians and health care providers, and that metabolic/bariatric surgery is a highly successful therapeutic option for this disease.

When is the Best Time to Initiate Peri-operative Heparin Therapy in General Surgery Patients? A Risk-Benefit Dilemma

We sought optimal timing for heparin therapy in general surgery (GS) patients. From 2001 to 2008, 95 GS patients with documented thromboembolic events (TE) were identified and compared with matched controls (age, gender, type of operation, date of operation, malignancy, and body mass index [BMI]). Timing of heparin therapy, characteristics of TE or bleeding events, and risk factors for TE were collected. Mean age (57 years), BMI (33 kgM-2), gender (55% male), malignancy (53%), and duration of operation (204 vs 191 minutes, P = not significant) were similar in both groups. Peri-operative (within 24 hours) heparin administration (study 56% vs control 64%, P = 0.2) was no different. Preoperative therapy was more common in the control group (77% vs 51%, P = 0.001). The regression model showed a protective effect for heparin if given preoperatively (odds ratio = 0.37, P = 0.047) with no effect if started >10 hours from incision. Mean blood transfusion (97 and 106 mL) and hemorrhagic events (4.5% and 5%) were similar in both groups ( P = not significant). Median (range) length of hospital stay and mortality was higher in TE cases [19 (0-201) vs 6 (0-66) days, 11 vs 2 mortality in 100-person-years ( P < 0.05)]. Heparin administration before GS is associated with >2-fold reduction in TE. The optimal time to start heparin seems to be 1 to 10 hours before the time of incision.

[Recommendations for the peri-operative management of bariatric surgery patients: results of a national survey]

To standardise possible peri-operative bariatric surgery protocols, a survey was prepared to be filled in by members of the Spanish Society for Obesity (Sociedad Española de Cirugía de la Obesidad) (SECO), and to approve it at the XII National Congress. A total of 47 members of SECO from 14 autonomous communities responded, and it unanimously approved by the Congress. As highly recommended peri-operative procedures, were proposed: full laboratory analysis (98%) with an endocrine study (90%), ECG (96%), chest x-ray (98%), an oesophageal-gastric imaging test (endoscopy or gastro-duodenal transit study (98%), antibiotic prophylaxis (92%) and use of low molecular weight heparins pre-operatively (96%), and for 2 weeks (83%). Pre-surgical, abdominal ultrasound (86%), spirometry (80%), diet (88%) and psychological study (76%), and during surgery, use of elastic stockings (76%), leak tests (92%) and drainages (90%), were established as advisable procedures.