Prophylaxis of thromboembolism in bariatric surgery with parnaparin

Laparoscopic Sleeve Gastrectomy Affects Coagulation System of Obese Patients

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is nowadays the most popular bariatric procedure for obesity. However, whether LSG increases the risk of thrombosis remains unclear. The aim of this study was to investigate potential effects of LSG on coagulation system.

METHODS

Fifty-five obese patients underwent LSG between 2016 and 2018. The LSG was performed with pneumoperitoneum pressure maintained at 13 mmHg. Venous blood specimens were collected from each patient before surgery, at the end of pneumoperitoneum (i.e., 0 h after surgery), and at 24 h after surgery to determine prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), platelet count (PLT), D-dimer (D-D), red blood cell count (RBC), hematocrit (HCT), plateletcrit (PCT), cholesterol (CHOL), triglyceride (TRIG), and serum calcium (Ca). All patients were examined on the veins of the lower limbs by color Duplex sonography (CDS) before surgery and at 24 h after surgery, respectively.

RESULTS

All patients successfully underwent LSG. No severe surgery-related complications were observed during 1-month follow-up after operation. Preoperative BMI was 43.6 ± 8.3 kg/m². The levels of coagulation factors were within the normal range before surgery, except a relatively higher PLT. The PT and D-D were increased at 0 h and 24 h after surgery (P < 0.05), whereas APTT was decreased (P < 0.05). The postoperative FIB remained similar to the preoperative one (P > 0.05). The CDS identified no thrombus in the veins of the lower limbs, either before surgery or at 24 h after surgery.

CONCLUSIONS

LSG may cause postoperative hypercoagulability of patients with obesity.

Perioperative care of the obese patient

Background

Obesity has become an increasing problem worldwide during the past few decades. Hence, surgeons and anaesthetists will care for an increasing number of obese patients in the foreseeable future, and should be prepared to provide optimal management for these individuals. This review provides an update of recent evidence regarding perioperative strategies for obese patients.

Methods

A search for papers on the perioperative care of obese patients (English language only) was performed in July 2019 using the PubMed, Scopus, Web of Science and Cochrane Library electronic databases. The review focused on the results of RCTs, although observational studies, meta-analyses, reviews, guidelines and other reports discussing the perioperative care of obese patients were also considered. When data from obese patients were not available, relevant data from non-obese populations were used.

Results and conclusion

Obese patients require comprehensive preoperative evaluation. Experienced medical teams, appropriate equipment and monitoring, careful anaesthetic management, and an adequate perioperative ventilation strategy may improve postoperative outcomes. Additional perioperative precautions are necessary in patients with severe morbid obesity, metabolic syndrome, untreated or severe obstructive sleep apnoea syndrome, or obesity hypoventilation syndrome; patients receiving home ventilatory support or postoperative opioid therapy; and obese patients undergoing open operations, long procedures or revisional surgery.

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.

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.

Laparoscopic gastric band migration: role of environmental factors in the experience of a single team in three operating rooms

Stomach erosion after gastric banding represents one of its least studied complications, despite the fact that the modalities of presentation and treatment have been clarified in recent years. Associations between this complication and specific surgical factors related to the patient have not been reported. We evaluated the incidence of this complication in various operating environments, to identify a possible association with a specific risk factor. A total of 250 patients underwent gastric banding between 2006 and 2008 and were followed for at least 1 year of follow-up. The procedure was performed in three Centers by the same surgical team. Center A was selected for the learning curve, in the initial phase of the study. All surgeries were performed with standardized techniques. An annual endoscopic evaluation was performed during first 12 months. The data from the three Centers were evaluated comparatively, to assess the incidence of migration and compare sterilization and perioperative preparation techniques. Between May 2006 and December 2008, 140 patients operated on at Center A, 70 at Center B, and 50 at Center C were included. Twelve cases of intragastric migration were observed (4.8% of the entire cohort): two cases at Center A (1.4%) and 10 cases at Center C (25%; A vs. C and A vs. B, p < 0.05); no cases of erosions were observed in Center B of 50 patients (0%; reviewer 1, comment 1). From a retrospective observation, no significant difference in sterilization techniques was observed, while there were differences in perioperative preparation, although these are not objectifiable parameters.

Update on the clinical use of the low-molecular-weight heparin, parnaparin

Parnaparin is a low-molecular-weight heparin that has widely shown its efficacy and safety in prevention of venous thromboembolism, in the treatment of chronic venous disorders, and in the treatment of venous and arterial (stable and unstable angina, acute ST-segment elevation myocardial infarction) thrombosis. Parnaparin at the respective dosages of 3200, 4250, 6400, or 12800 IUaXa for a period ranging from 3 to 5 days to 6 months, is usually administered subcutaneously by means of once-daily regimen and is better tolerated than unfractionated heparin at the injection site. In the variety of commercially available low-molecular-weight heparins, parnaparin represents a useful therapeutic option, even though little evidence is available comparing the superiority or the equivalent efficacy and safety of parnaparin to that of the unfractionated heparin or placebo. This review summarizes the available literature on the use of parnaparin in different settings of cardiovascular diseases, including papers published during the past year and ongoing studies.

Pharmacodynamics of low molecular weight heparin in patients undergoing bariatric surgery: a prospective, randomised study comparing 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.

AIM

The aim of this study was to evaluate the pharmacodynamic parameters of two doses of the LMWH parnaparin administered to patients undergoing bariatric surgery.

METHODS

Patients were enrolled in a multicentre, open label, pilot study and were randomised to receive 4250 IU/day [n=36; 30 females; median age: 38 years (23-56); median BMI: 46.7 Kg/m(2) (36.5-58.8)] or 6400 IU/day [n=30; 24 females; median age: 42 years (22-63); median BMI: 43.7 Kg/m(2) (36.1-64.1)] of parnaparin s.c. for 7-11 days. The pharmacodynamic effects of parnaparin were analysed by measuring the anti Factor Xa activity on day 0 (12 hours after the first parnaparin injection), day 4 and day 6 after surgery (before and 4 hours after parnaparin administration).

RESULTS

In 98.3% of patients receiving 4250 IU/day the peak anti-Xa levels were in the range of 0.1-0.4 IU/ml. Higher anti-Xa levels were observed in patients receiving 6400 IU/day: in 62.3% of these patients the peak anti-Xa levels were greater than 0.4 IU/ml. The anti-Xa levels measured 4 hours after injection on days 4 and 6 were not statistically correlated with BMI for either dose of parnaparin (p=0.077 and p=0.401 for 4250 or 6400 IU/day, respectively).

CONCLUSION

The dose of 4250 IU/day seems adequate to achieve prophylactic anti-Xa levels in morbid obese patients undergoing bariatric surgery. Conversely, most of the patients receiving 6.400 IU/day show anti-Xa levels higher than the recommended prophylactic values.

Weight-based dosing of enoxaparin for VTE prophylaxis in morbidly obese, medically-Ill patients

INTRODUCTION

In clinical trials, fixed-dose enoxaparin (40 mg once daily) reduces the risk of venous thromboembolism (VTE) in medically-ill patients. However, morbidly obese patients were under-represented in these trials and using fixed-dose enoxaparin in obese patients may be inadequate. We completed a pharmacokinetic study in morbidly obese, medically-ill patients to determine if weight-based dosing of enoxaparin for VTE prophylaxis was feasible, without excessive levels of anticoagulation, as determined by peak anti-Xa levels.

MATERIALS AND METHODS

Twenty eight morbidly obese (BMI>or=35 kg/m(2)) patients were enrolled and completed the study protocol. Enoxaparin 0.5 mg/kg was administered once daily subcutaneously and peak anti-Xa levels were measured approximately 4-6 hours after the enoxaparin dose.

RESULTS AND CONCLUSIONS

Overall, 46% of patients were female, the average age (+/-SD) was 54 (+/-11) years, and the average weight and BMI were 135.6 kg (+/-25.3) and 48.1 kg/m(2) (+/-11.1), respectively. The average daily dose of enoxaparin was 67 mg (+/-12). The average peak anti-Xa level was 0.25 (SD+/-0.11, range 0.08 to 0.59) units/mL. Peak anti-Xa levels did not significantly correlate with weight or BMI. There were no bleeding events, symptomatic VTE, or significant thrombocytopenia. In morbidly obese, medically-ill patients, use of weight-based enoxaparin dosed at 0.5 mg/kg once daily is feasible and results in peak anti-Xa levels within or near recommended range for thromboprophylaxis, without any evidence of excessive anti-Xa activity. These data suggest that this weight-based regimen may be more effective than standard fixed-dose enoxaparin. Clinical outcome studies are warranted to determine the clinical safety and efficacy of this regimen.

Clinical use of parnaparin in major and minor orthopedic surgery: a review

Patients undergoing arthroplasty or other orthopedic surgery show a high risk of venous thromboembolism (VTE), involving mortality, morbidity, and social costs; however, the risk for VTE in minor orthopedic surgery should not be underestimated and antithrombotic prophylaxis may be required. According to the literature, low-molecular-weight heparins (LMWHs) are more effective in preventing VTE than unfractionated heparins (UFHs) or vitamin K antagonists, and have a lower hemorrhagic risk. By comparing different prophylactic regimens, it has been shown that starting the prophylaxis near the time of the operation is the most critical point for efficacy, whether or not the first dose is administered pre- or post-operatively. Moreover, most thromboembolic complications are observed after discharge and, therefore, many clinicians advocate continuing prophylaxis for longer times (6–8 weeks) in order to further reduce the rate for VTE. The literature on parnaparin, a new LMWH, in VTE prophylaxis was reviewed. Parnaparin is equally effective as UFH, but it offers the advantages of a once-daily administration and improved tolerability, thus allowing the home management of patients with no need for laboratory coagulation tests.