Systemic coagulation and fibrinolysis after laparoscopic and open gastric bypass

Predictive factors of thromboembolic events in patients undergoing Roux-en-Y gastric bypass

BACKGROUND

Obesity is a major risk factor for postoperative deep venous thrombosis (DVT) and pulmonary embolism (PE). Identifying those patients at the greatest risk for DVT/PE is essential to prevent thromboembolic events among patients undergoing Roux-en-Y gastric bypass (RYGB) for clinically significant obesity. This aim of the study is to identify factors associated with an increased likelihood of developing DVT/PE after RYGB.

METHODS

Prospectively collected data from 660 consecutive patients who underwent RYGB were reviewed. Patients received perioperative prophylaxis with low molecular weight heparin and sequential compression devices. Diagnosis was based on clinical, radiologic, and/or necropsy findings. Patients with and without postoperative DVT/PE were compared using chi(2) and multivariate logistic regression analysis.

RESULTS

A total of 23 patients (3.5%) developed postoperative DVT/PE. Age > 50 years (P = .04), previous DVT/PE (P = .02), history of smoking (P < .01), revisional operation (P = .03), open RYGB (P = .02), and anastomotic leak (P < .0001) significantly increased the likelihood of developing DVT/PE. On the other hand, gender, body mass index > 50 kg/m(2) and history of sleep apnea, hypertension, diabetes, or myocardial infarction did not increase the likelihood of DVT/PE. Multivariate analysis revealed that age > 50 years (P = .04), postoperative anastomotic leak (P < .001), smoking (P < .01), and previous DVT/PE (P < .001) increased the likelihood of postoperative DVT/PE.

CONCLUSIONS

Age > 50 years, anastomotic leak, smoking, and history of DVT/PE all increase the likelihood of postoperative thromboembolic events in patients undergoing RYGB. Further preoperative screening and/or postoperative prophylaxis may be needed in this subset of high-risk patients.

The impact of laparoscopy on bariatric surgery

The rising popularity of bariatric surgery over the past several years is attributable in part to the development of laparoscopic bariatric surgery. Morbidly obese patients have associated comorbid conditions that may predispose them to postoperative morbidity. The laparoscopic approach to bariatric surgery offers a minimally invasive option that reduces the physiologic stress and provides clinical benefits, as compared with the open approach. This review summarizes the impact of laparoscopic surgery on bariatric surgery, the various risk factors that could potentially predispose morbidly obese patients to postoperative morbidity, the fundamental differences between laparoscopic and open bariatric surgery, and the physiology of reduced tissue injury associated with laparoscopic bariatric surgery.

Video laparoscopic surgery: is out-of-hospital thromboprophylaxis necessary?

Despite widespread use of laparoscopic procedures, no adequate data are available to support specific recommendations for venous thromboprophylaxis in patients undergoing laparoscopic surgery. This prospective, randomized trial is the first to be designed to evaluate a regimen of out-of-hospital thromboprophylaxis after laparoscopic surgery. Consecutive patients admitted for laparoscopic surgery were considered for the study. The thromboprophylaxis regimen used for each patient was based on a risk score. Possible thromboprophylactic measures included elastic stockings and pre- and postoperative Dalteparin or early ambulation. At discharge, patients were randomly allocated either to continue Dalteparin for 1 week, or to receive no further prophylaxis. Patients judged to be at low risk were not randomized. Compression ultrasound of the leg veins was performed in all patients 4 weeks after hospital discharge. Fifty-three patients, all with acute appendicitis, were judged to be at low risk of deep vein thrombosis and were not included in the randomized study. The remaining 209 patients fell into two groups: 104 patients received postdischarge Dalteparin and 105 patients did not. The incidence of deep vein thrombosis was 0% (0 of 104) vs. 0.95% (one of 105), respectively (P = 1.00). The risk of postdischarge venous thromboembolism is low in patients undergoing laparoscopic surgery who receive in-hospital thromboprophylaxis. Given this low risk, a clinical trial powered to determine if extending prophylaxis in such patients reduces the risk of clinically apparent deep vein thrombosis would be unfeasibly large.

Fluid administration during abdominal surgery influences on coagulation in the postoperative period

OBJECTIVE

Postoperative coagulopathy is an important concern for patients after major surgery. Our objective was to define the factors that correlate with postoperative deterioration in coagulation.

DESIGN

Retrospective clinical case study.

SETTING

University hospital.

PARTICIPANTS

Adult patients (n = 150), who underwent major abdominal surgery, were randomly chosen to participate in the study. For each patient, demographic and medical data, anesthetic information, type and duration of surgery, hemodynamic variables, fluid administration, as well as preoperative and postoperative prothrombin time and partial thromboplastin time were collected. Statistical analysis was used to determine which factors correlated with deterioration of coagulation tests.

RESULTS

We found statistically significant correlation between deteriorating coagulation functions and administration of more than 3 l of crystalloids during abdominal surgery. There was also correlation between administration of more than 500 ml of colloid administration and elongation of protrombin time. The remainder of the above studied factors did not correlate with deteriorating coagulation.

CONCLUSIONS

Administration of more than 3-l crystalloids or 500-ml colloids during abdominal surgery correlates with postoperative coagulopathy.

Role of fibrin D-dimer testing in emergency medicine

OBJECTIVES

Systemic values of the fibrinolytic plasma marker fibrin D-dimer are raised in a variety of acute clinical conditions. D-dimer values can now be rapidly determined and used to aid diagnosis in emergency medicine. However, despite clinical guidelines, inappropriate and unnecessary measurement of D-dimer values is a significant clinical problem. An understanding of the pathophysiological basis and limitations of the value of D-dimer values may help reduce this problem. This review discusses the pathophysiology of the fibrinolytic system. The currently used assays, clinical indications, and limitations of D-dimer measurement are reviewed. Finally, the potential future clinical indications for measurement of D-dimer values in emergency medicine are discussed.

METHODS

Literature on D-dimer was identified from Medline, along with cross referencing from the reference lists of major articles on the subject

RESULTS

and conclusions: Systemic D-dimer values aids diagnosis, and is potentially a prognostic indicator, in a variety of clinical conditions in emergency medicine. However, it has limited specificity in patients with comorbid conditions. Although, currently, there is no standard D-dimer assay, immunoturbidimetric assays are the most suitable for use in emergency medicine