Effectiveness and safety of CT-guided drainage of abdominal abscesses with small and extra-small-bore drains: a single-centre observational study

Introduction
Computed tomography (CT)-guided percutaneous drainage is an established method for the treatment of abdominal abscesses. The purpose of this study is to evaluate the effectiveness and safety of drainage of abdominal abscesses with small-bore (6F and 9F) drains.

Material and methods
The analysis of a prospectively maintained database included 135 consecutive patients from a single centre with abdominal or pelvic abscesses, who underwent CT-guided drainage. Procedures were performed using a one-step trocar technique with 6F (40 procedures) or 9F (95 procedures) catheters. Technical success was defined as insertion of the drain into the abscess cavity and aspiration of the fluid sample. Clinical success was defined as resolution of infection without surgical intervention or upsizing of the drain.

Results
The mean size of abscesses was 77.0 ± 28.8 mm (32-220 mm). Thick fluid was aspirated from 129 collections; 6 collections contained thin fluid. Technical success was achieved in 100% of procedures. Clinical success was achieved in 94.8% of patients. Surgical drainage was necessary in 3.7% of patients and upsizing in 1.5% of patients. Complications of Clavien-Dindo grade III were noted in 2.2% of patients without grade IV or V adverse events. The mean radiation dose in terms of Dose Length Product was 617 ± 467 mGy x cm. The mean procedure time was 28.0 ± 11.3 min.

Conclusions
CT-guided drainage of abdominal abscesses with small- and very small-bore drains is usually sufficient to obtain clinical success with a low complication rate in the case of thick fluid collections.