Point-of-care measurement of C-reactive protein promotes de-escalation of treatment decisions and strengthens the perceived clinical confidence of physicians in out-of-hours outpatient emergency medical services.

Objectives: Out-of-hours outpatient emergency medical services (OEMS) provide healthcare for patients with non-life-threatening conditions in need for urgent care when outpatient practices are closed. We studied the use of point-of-care-testing of C-reactive protein (CRP-POCT) at OEMS.

Design: Cross-sectional questionnaire-based survey.

Setting: Single centre OEMS practice in Hildesheim, Germany (October 2021 to March 2022).

Participants: OEMS physicians answering a questionnaire immediately after performing CRP-POCTs (CUBE-S Analyzer, Hitado) on any patients.

Primary And Secondary Outcomes: Impact of CRP-POCTs on clinical decision-making and perceived usefulness.

Results: In the 6-month study period, 114 valid CRP-POCTs were performed in the OEMS practice by 18 physicians and the questionnaire was answered in 112 cases (response rate: 98.2%). CRP-POCTs were used in the diagnosis of inflammatory diseases of the gastrointestinal tract (60.0%), respiratory tract infections (17.0%), urinary tract infections (9.0%) and other non-gastrointestinal/non-specified infections (11.0%). The use of a CRP-POCT resulted in a change of the physicians' clinical decision in 83.3% of the cases. Specifically, in 13.6% and 35.1% of the cases, rapid CRP measurements led to decision changes in the (1) initiation of antimicrobial therapy and (2) other drug treatment, respectively. Notably, in 60% of all cases, the use of a CRP-POCT reportedly changed the decision on hospitalisation/non-hospitalisation of OEMS patients. In respect of antimicrobial therapy and hospitalisation, these decision changes primarily (≥73%) promoted 'step-down' decisions, that is, no antibiotic therapy and no hospital admission. In the great majority of CRP-POCT applications (≥95%), OEMS physicians reported that rapid CRP measurements increased the confidence in their diagnostic and therapeutic decision. In almost all cases (97%), physicians rated the CRP-POCT use as useful in the treatment situation.

Conclusion: Quantitative CRP-POCT promotes step-down clinical decisions and strengthens the clinical confidence of physicians in out-of-hours OEMS.