P085 Hypercoagulability in patients undergoing abdominopelvic surgery for inflammatory bowel disease: insights from thromboelastography
Authors: Stefan Holubar , Hin Angus Lee Chun , Adina Feinberg , Olga Lavryk , Florian Rieder , Miguel Regueiro , Luca Stocchi , Tracy Hull , Scott Steele 
Published: July 2019

BACKGROUND:
Hypercoagulability in patients with inflammatory bowel disease (IBD) is a hematological extra-intestinal manifestation thought to be driven by the gut inflammatory response. However, mechanisms driving the coagulation abnormalities are poorly understood. The aim of this study is to characterize coagulation profiles in IBD surgical patients using thromboelastography (TEG).

METHODS:
A single center, single surgeon retrospective study was performed after IRB approval. Consecutive patients with Crohn's disease (CD) or ulcerative colitis (UC) who underwent bowel surgery from June to September 2018 were included. All patients (100%) received perioperative VTE chemoprophylaxis. Clinical data was collected by retrospective chart review. Hypercoagulability profile based on TEG results was defined by any combination of: (1) low R-value, (2) high degree angle, (3) high maximum amplitude (MA), (4) elevated coagulation index. Short-term (30-day) surgical outcomes including length of stay (LOS), readmission, reoperations, and major (Clavien-Dindo grade 3/4) complications were reported. Figures represent frequency (proportion) or median (range).

RESULTS:
A total of 19 IBD patients had a TEG prior to surgery. The age was 33 (23–70), more were women (63%, n = 12) and most patients had CD (78%, n = 15). Overall 11 (58%) of patients were receiving steroids and 10 (53%) had were receiving biologics, while 6 (32%) of patients were hospitalized pre-operatively. Surgery was laparoscopic in 11 (58%) with 1 conversion to laparotomy. All patients (100%) received VTE chemoprophylaxis peri-operatively. Overall, 14 (74%) patients had a hypercoagulable TEG profile with 7 of these patients (50%, or 37% overall) having more than one hypercoagulable TEG parameter. A high MA (platelet hyperfunction) in 7 (37%) patients, and 8 (42%) patients had high degree angle (increased fibrinogen concentration/function), and 8 (42%) patient had low R-value (hyperfunctioning coagulation cascade). The coagulation index, indicating hypercoagulability, was abnormally high in 2 (10%) patients. The overall median LOS was 7 days (1, 42). Clavien-Dindo grade 3 complications occurred in 3 (16%) patients; there were no unplanned reoperations, while 3 (16%) of patients were re-admitted. A total of 16 of 18 eligible patients (88%) received extended post-discharge VTE chemoprophylaxis; one patient (5.5%) with unexplained tachycardia was diagnosed with a groin VTE 14 days post-operatively prior to discharge and required anticoagulation (TEG parameters: low R-value, high degree angle, and high coagulation index. Another patient had superficial thrombophlebitis related to a midline but did not require anticoagulation; this patient had a low R-value. Thus any VTE occurred in 2 (14%) of those with hypercoagulable TEG profiles and in zero of those with normal TEG profiles.

CONCLUSION(S):
We observed that the majority of surgical IBD patients have a hypercoagulable TEG profile, and patients with evidence of hypercoagulability on thromboelastography may be at increased risk of post-operative VTE. Our data suggests, given the mutlifactorial nature of hypercoaguability in these patients, novel VTE chemoprophylaxis approaches are needed.