Is routine imaging necessary prior to percutaneous abscess catheter removal?

Routine management after abscess drainage includes CT or fluoroscopic imaging to assess for residual abscess cavity prior to catheter removal. It is unclear whether this practice is necessary in patients without residual infection signs and symptoms.

To evaluate safety of abscess catheter removal without follow-up imaging in patients without residual clinical or laboratory signs of infection and catheter output < 10 cc/day for 2 consecutive days.

In this IRB-approved, HIPAA compliant, retrospective study, consecutive patients that underwent percutaneous CT-guided drainage of a single abdominal or pelvic abscess between 01/2015 and 12/2017 in a single tertiary academic institution with or without follow-up imaging prior to catheter removal were included. In our institution, catheters are routinely removed without imaging if there are no clinical (fever, pain) or laboratory (elevated WBC count) signs of infection and catheter output is < 10 cc/day for 2 consecutive days. Patients' and abscess's characteristics, repeat imaging data, and need for re-interventions were obtained through medical records review. Statistical analysis was performed with Fisher's exact test for independent data and Student's t-test for comparison of group means.

310 consecutive patients (age 56 ± 16 years, 48% female) were included in the study. In 265/310 (85%) patients, no routine follow-up imaging prior to catheter removal was obtained. In 2/265 (0.8%, 95% CI 0.02-0.27%) patients without routine pre-removal imaging, repeat abscess drainage was required 6 and 15 days after catheter removal in patient with perforated appendicitis and after laparoscopic renal cyst decortication, respectively. No patients, 0/45 (0%, 95% CI 0-0.07), that underwent routine imaging without clinical or laboratory signs infection needed to undergo a repeat abscess drainage.

There is a low rate (0.8%) of abscess recurrence if percutaneous abscess catheter is removed at the time cessation of drainage without routine imaging in clinically well patient.