Management

The most effective management of a subphrenic abscess is drainage. This may be achieved under ultrasound control or via an open operation.

Percutaneous drainage is the least invasive and just as effective as surgical drainage and is currently the standard of care. CT guided drainage with interventional radiology is highly effective and can prevent the morbidity and mortality associated with surgical drainage. (1)

Transmural drainage has been developed using endoscopic ultrasound (EUS-TD). It is beneficial due to the real-time visualization of the abscess cavity, the use of Doppler to avoid major vessels, and the high success rate. (2)

If the abscess is diagnosed early and has no air or fluid level then this may be treated with broad-spectrum antibiotics, e.g. gentamicin, benzylpenicillin, and metronidazole.

Guidelines suggest 96 hours of antibiotic treatment for well-controlled intrabdominal sepsis and 5-7 days for those without a definitive source control procedure (3)

If the patient remains symptomatic for more than 5 days then conservative management should be abandoned and abscess drainage performed.

(Note that gentamicin levels should be measured regularly and doses of gentamicin should be reduced if there is renal impairment.)

Reference

1. Bufalari A, Giustozzi G, Moggi L. Postoperative intra-abdominal abscesses: percutaneous versus surgical treatment. Acta Chir Belg. 1996 Sep-Oct;96(5):197-200.
2. Morita S, Kamimura K, Suda T, Oda C, Hoshi T, Kanefuji T, Yagi K, Terai S. Endoscopic ultrasound-guided transmural drainage for subphrenic abscess: report of two cases and a literature review. BMC Gastroenterol. 2018 Apr 27;18(1):55.
3. Mazuski JE, Tessier JM, May AK, Sawyer RG, Nadler EP, Rosengart MR, Chang PK, O'Neill PJ, Mollen KP, Huston JM, Diaz JJ, Prince JM. The Surgical Infection Society Revised Guidelines on the Management of Intra-Abdominal Infection. Surg Infect (Larchmt). 2017 Jan;18(1):1-76