P23 Procalcitonin testing in acute infection to guide antibiotic course lengths in the ICU as a tool for antibiotic stewardship

TL;DR

This study examines how often procalcitonin (PCT) testing is used in an ICU to guide antibiotic use, finding low adherence to protocols and limited impact on decision-making.

Contribution

The study evaluates local adherence to PCT testing protocols in an ICU for antibiotic stewardship during the post-COVID-19 period.

Findings

Only 45% of antibiotic courses had a baseline PCT test ordered.

Antibiotic courses in the ICU averaged 2.98 days, with limited PCT-guided decisions.

PCT testing was inconsistent with the proposed local algorithm.

Abstract

Procalcitonin (PCT) was introduced into the ICU during the COVID-19 pandemic. PCT enables optimization of antibiotic course lengths for ICU patients, positively impacting antimicrobial stewardship.

To evaluate local adherence to PCT testing for patients with suspected acute bacterial infections in an ICU in England.

Patients discharged from the ICU between 1 November and 30 November 2023 were identified. PCT test timing, frequency, PCT level, antibiotic course lengths (both in the ICU and after ICU discharge) and infection diagnosis were extracted. Adherence to a proposed local PCT testing protocol was determined and the medical notes reviewed for evidence of PCT guided antibiotic decision making.

Of 65 patients discharged from ICU, 49 (75.4%) received antibiotics during their ICU stay. Thirty-six (77.6%) of these patients had 40 antibiotic courses for suspected acute bacterial infections. A baseline PCT was ordered in 18/40 (45.0%), a repeat PCT ordered in 6 (46.2%) antibiotic courses. The median antibiotic course length for acute infection in the ICU was 2.98 days (IQR 1.72–4.73), with little evidence of PCT-guided antibiotic decision making.

Within our ICU, PCT measurement is sporadic and often not in accordance with the proposed local PCT-testing algorithm. Antibiotic course lengths, both during the ICU stay and total antibiotic courses, were short.