Photoplethysmography as a New Prognostic Method to Predict Sepsis at First Clinical Presentation

Abstract

Background: Accurate prediction of clinical deterioration is critical in guiding clinical decisions for patients with infections in the emergency department (ED). Current scoring systems exhibit limitations in their predictive accuracy, or they are not explicitly designed for predicting deterioration. Hence, there is a need for the development of innovative predictive tools. We assessed whether photoplethysmography (PPG) waveforms obtained within 20 minutes after arrival to the ED can predict clinical deterioration among patients with infections at risk for sepsis development.

Methods: We conducted a secondary analysis of prospectively obtained data from the Acutelines data-biobank, involving 576 patients with an infection at the ED. Clinical and demographic data, vital signs, laboratory values, and PPG waveforms were collected. The primary endpoint of clinical deterioration comprised of ICU admission and/or in-hospital mortality within 72 hours. Logistic regression models assessed associations between PPG features, national early warning score (NEWS), and the primary endpoint of clinical deterioration.

Findings: The systolic peak amplitude (SPA), diastolic peak amplitude (DPA), pulse width (PW), pulse interval (PI), and APG b/a ratio were different between patients with clinical deterioration and those who did not. The SPA, DPA, PW, PI, APG b/a-ratio, and NEWS predicted clinical deterioration. Using multivariate regression analysis, we revealed an independent association of the SPA and APG b/a ratio with clinical deterioration that existed after adjusting for the NEWS.

Interpretation: This study highlights the potential utility of PPG as a valuable tool for predicting the deterioration of early sepsis patients. Specific PPG waveform features (i.e., SPA, APG) independently predict clinical deterioration. As a clinical consequence, developing algorithms based on PPG waveform features may improve early prediction of deterioration compared to current tools like NEWS.

Note: Funding Information: The research is supported by a MD/PhD grant awarded to Ms. S. Ter Horst by the UMCG.

Declaration of Interests: The authors declare no conflicts of interest.

Ethics Approval Statement: We conducted a secondary analysis of prospectively obtained data by Acutelines. A deferred consent procedure (by proxy) was in place to enable the collection of data and biomaterials before obtaining written consent. When reaching the patient or proxy was not feasible, we followed an opt-out procedure. Acutelines is approved by the medical ethics board of the UMCG and registered under trial registration number NCT04615065 at ClinicalTrials.gov.

Keywords: sepsis, emergency department, photoplethysmography, waveform, Intensive Care Unit, mortality