Incidence of Splanchnic Vein Thrombosis After Abdominal Surgery: A Systematic Review and Meta-analysis

BACKGROUND: Abdominal surgery may increase the risk of splanchnic vein thrombosis (SVT). We determined the incidence of SVT after abdominal surgery and identified groups at highest risk. MATERIALS AND METHODS: MEDLINE and Embase were searched for clinical studies evaluating the incidence of postoperative SVT after abdominopelvic surgery. Study selection, data abstraction, and risk of bias assessment were carried out independently by two reviewers. Clinical heterogeneity was explored by subgroup analyses (i.e., type of intra-abdominal procedure and organ group). RESULTS: Of 5549 abstracts screened, 48 were analyzed. Pooled incidence of SVT (n = 50,267) was 2.68% [95% confidence interval (CI), 2.24 to 3.11] (1347 events), I² = 96%. Pooled incidence of SVT in high-risk procedures were splenectomy with devascularization (24%), hepatectomy in patients with cirrhosis (9%), and pancreatectomy with venous resection (5%). Pooled incidence of symptomatic and asymptomatic SVT was 1.02% (95% CI: 0.97% to 1.07%) and 0.98% (95% CI 0.88% to 1.07%), respectively. Most common causes of SVT-related mortality were irreversible thrombosis, bowel ischemia, liver failure, and gastrointestinal bleed. Most studies included were at a high risk of bias due to lack of prospective data collection and lack of SVT screening for all participants. CONCLUSIONS: Incidence of SVT after abdominal surgery is low but remains a relevant complication. Patients undergoing procedures involving surgical manipulation of the venous system and splenectomy are at the highest risk. Given the life-threatening risks associated with SVT, there is a need for larger prospective studies on the incidence and impact of SVT after abdominal surgery.