Post-surgical fluid collections (PSFCs) are a common complication of gastrointestinal surgery and are usually managed by percutaneous drainage. Emerging data suggests that endoscopic ultrasound (EUS) guided drainage of PSFCs may be a safe and effective alternative. The aim of this study was to assess the technical feasibility, safety and efficacy of EUS-guided drainage of PSFCs.

Retrospective, multi-centre cohort study assessed all patients referred for EUS-guided drainage of symptomatic PSFCs after hepatobiliary, upper GI or colorectal surgery at two tertiary referral centres in Australia from 1^st January 2016 to 31^st December 2022. Primary outcome measures were technical success (ability to access and drain a PSFC by placement of a transmural stent), clinical success (complete clinical resolution of symptoms and reduction/resolution of PSCF on CT at 3 months) and rate of adverse events, with major adverse events defined as grade III or above on the Clavien Dindo Classification.

Forty-two patients were referred for EUS-guided drainage of PSFCs (median age 61 years (IQR, 46–71); 25 (60%) male). The most common index surgery was pancreatic (N=19, 45%) and the primary indication for drainage was sepsis (N=29, 69%). Mean collection size was 53mm (IQR, 41-91mm). EUS was performed at a median of 30 days (IQR, 19-69 days) post-surgery; 19 (45%) were done in <4 weeks of PSFC development. EUS-guided drainage was attempted in 34 (81%) patients with 100% technical success. Eight patients were excluded at EUS due to unsuitable collection morphology, including PSFC too small or not identified, n=5; immature PSFC wall, n=2; PSFC not abutting the GI lumen, n=1. Clinical success was achieved in 33/34 (97%) patients who underwent EUS-guided drainage; one patient had symptom resolution post drainage however follow up CT showed an increase in the size of the PSFC. A single EUS-guided drainage was performed in 29 (85%) patients; 5 (15%) patients required >1 endoscopic procedure with a median number of drainages of 2 (IQR, 1-2). There were no intra-procedural complications. Nine (26%) post-procedural adverse events occurred, of which 9 (33%) were classified as major adverse events.

EUS-guided drainage of PSFCs is technically feasible, can be safely performed early following PSFC formation in a significant proportion of patients and achieves high rates of clinical success with few major adverse events. This technique offers a minimally invasive alternative to percutaneous drainage, avoiding the need for an external drain with attendant risk of blockage, dislodgement, and infection. EUS-guided drainage should be considered as a therapeutic option for patients with PSFCs after GI surgery.