Portomesenteric venous thrombosis after laparoscopic sleeve gastrectomy: A case report and a call for prevention.

Postoperative portomesenteric venous thrombosis (PMVT) is being increasingly reported after bariatric surgery. It is variable and often a nonspecific presentation along with its potential for life-threatening and life-altering outcomes makes it imperative that it is prevented, detected early and treated optimally. We report the case of a 50-year-old morbidly obese man undergoing a laparoscopic sleeve gastrectomy who developed symptomatic PMVT two weeks postsurgery, which was successfully treated by anticoagulant therapy. We provide postulates to the etiopathological mechanism for this thrombotic entity. The growing recognition that obesity and bariatric surgery create a procoagulant state regionally and systemically provides impetus for designing the ideal protocol for PMVT prophylaxis, which could be more common than currently believed. We support the early screening for PMVT in the postbariatric surgical patient with unexplainable or intractable abdominal symptoms. The role of routine surveillance and the ideal duration of post-PMVT anticoagulation is yet to be elucidated.

INTRODUCTION

Postoperative portomesenteric venous thrombosis (PMVT) is a potentially devastating morbidity, occurring after gastrointestinal and laparoscopic surgeries.[1] PMVT is reported in bariatric surgery patients too. The procoagulant obese state, laparoscopy, and manipulation of the portomesenteric venous system (PMVS) probably contribute to PMVT. Intestinal devitalization is the most feared consequence. Often nonspecific in presentation, diagnosis is made through a high index of suspicion and imaging. Surgical intervention is indicated when intestinal viability is compromised. In nonapoplectic PMVT, anticoagulation prevents clot propagation and is associated with decreased recurrence and mortality. Chronic PMVT can manifest as portal hypertension or is diagnosed incidentally.[2] Awareness of this surgical morbidity is limited in the surgical community. We report a case of superior mesenteric venous thrombosis, which was detected after laparoscopic sleeve gastrectomy (LSG) and was successfully managed.

CASE REPORT

An LSG was performed for a 50-year-old morbidly obese (body mass index- 52 kg/m2), hypertensive, and sleep apnoeic patient. He was administered Inj. Clexane (Enoxaparin) 60 mg (Sanofi-Aventis, Surrey, UK) subcutaneously 12 hours before surgery. A thigh-length graduated compression elastic stocking was applied to the lower limbs before shifting to the operation theater, supplemented by thigh-length intermittent pneumatic compression (IPC) device (Kendall SCD Express, Covidien, MA, USA) applied prior to induction of anaesthesia till ambulation the next morning. The graduated compression elastic stocking was in place till normal ambulation. A four-port technique was employed along with liver retraction provided by a Nathanson liver retractor. Gastrolysis was performed by ultrasonic shears (Harmonic Ace, Ethicon Endo-Surgery, Puerto Rico, USA). Alesser curve gastric sleeve was created using the Echelon Flex 60 stapler (Ethicon Endo-Surgery, Cincinnati, Ohio, USA) with six-row cartridges (Endoscopic Linear Cutter Reloads, Ethicon Endo-Surgery) over an endoluminal bougie (12.7 mm [38 Fr] Gastric Calibration Tube, Ethicon Endo-Surgery). The suture was imbricated with continuous 2-0 polydiaxonone sodium (PDS) suture (Ethicon Endo-Clip Suture, Ethicon). Intraoperative endoscopy was performed to confirm gastric sleeve size, hemostasis and integrity. A Jackson Pratt drain (Biovac™, Biometrix, The Netherlands) was then placed along the staple line. The procedure lasted 135 min and was performed under a 15 mmHg carboperitoneum. The portomesenteric circulation was not visualized or manipulated. The patient was ambulated and introduced to clear liquids day 1 postoperatively after an upper gastrointestinal gastrograffin contrast study demonstrated the integrity of the gastric sleeve. On postoperative day 2, oral liquids were progressed. He was discharged on postoperative day 3 after removal of the surgical drain and was on daily subcutaneous low molecular weight heparin (Inj. enoxaparin 60 mg) for 5 days postoperatively.

The patient presented with progressive central abdominal pain and nausea, 15 days after LSG. On examination, he was found to be afebrile and having normal vital parameters. Abdominal examination was normal. Laboratory examinations were normal. A contrast-enhanced computed tomography (CECT) was performed to screen the very obese abdomen, which revealed thrombosis of the superior mesenteric vein (SMV) extending till the portal confluence with dilatation of proximal small bowel [Figures 1 and 2].

Figure 1

Abdominal noncontrast computed tomogram demonstrating superior mesenteric vein pathology

Figure 2

Abdominal contrast-enhanced computed tomogram demonstrating superior mesenteric vein thrombosis

There was no history of other risk factors for thrombosis. He was started on subcutaneous low molecular weight heparin (Inj.fraxiparine 5700 units subcutaneously twice daily). With continued anticoagulation, the patient became asymptomatic within a week and was discharged on oral warfarin anticoagulation. The patient remained asymptomatic and completed a 3-month course of oral anticoagulation in consultation with a vascular physician. A follow-up scan at 2 months revealed no thrombus in the SMV and a hematological workup for thrombophilia revealed no thrombophilic disposition. The patient has remained symptom free 18 months after the episode.

DISCUSSION

PMVT has occurred after laparoscopic gastric bypass and gastric banding. It is now reported after LSG too.[1] To our knowledge, more than 30 cases of PMVT have been reported after an LSG accounting for 0.3%-1% of post-LSG morbidity.[14] The clinical presentation is variable and ranges from subtle, nonspecific abdominal discomfort to severe pain with most cases presenting about 2 weeks postsurgery and being symptomatic about 2 days before presentation.[14] Physical findings range from normal to peritonism and shock. Considering the nonspecific presentation, it is likely that its true incidence is underestimated. The best initial imaging modality to confirm the diagnosis currently is an abdominal Doppler ultrasound or CECT. Invasive investigations are usually unnecessary. The management of PMVT post-bariatric surgery, is contingent on the length and viability of the affected segment of the bowel. This ranges from administering anticoagulation therapy to major bowel resection. The duration of post-thrombotic anticoagulation is contingent on underlying thrombophilic states and reports in literature range from 6 months to a year for those without, to life-long prophylaxis for those with pre-existing thrombophilia. We advocate a close follow-up with noninvasive imaging modalities to confirm dissolution of thrombus and prevent recurrence. Anticoagulation was discontinued at 3 months as the patient remained asymptomatic, became PMVT-free, and to mitigate the risk of bleeding due to continued anticoagulation.

A prothrombotic state secondary to pre-existing thrombophilia, morbid obesity, medications, laparoscopy, and possible operative manipulation or interruption of segments of the PMVS, probably contributes to postbariatric PMVT.[134] Considering the not uncommon incidence of this serious morbidity and the procoagulant state in bariatric surgery, certain authors have prompted the listing of PMVT as a formal complication of bariatric surgery and its inclusion in the clinical differential for abdominal pain after bariatric surgery.[5] We suggest that a high index of suspicion be maintained postbariatric surgery to detect and promptly treat PMVT. All bariatric surgical patients complaining of nonresolving abdominal discomfort or pain in the postoperative period should be evaluated for PMVT by noninvasive imaging! The current experience is nascent, but growing evidence could lead to the routine surveillance of PMVT in the postbariatric surgical patient. The ideal duration of postevent anticoagulation is yet to be defined. As bariatric surgery grows in volume, PMVT may increasingly be prophylaxed for, screened for, found, and treated.