Abstract
Background
Early warning scores reliably identify patients at risk of imminent death, but do not provide insight into what may be wrong with the patient and what to do about it.
Objectives To explore if the shock index (SI), pulse pressure (PP) and ROX index can place acutely ill medical patients in pathophysiologic categories that could indicate the interventions required.
Methods A retrospective post-hoc analysis of previously obtained and reported clinical data on 45,784 acutely ill medical patients admitted to a major regional referral Canadian hospital between 2005 and 2010 and validated on 107,546 emergency admissions to four Dutch hospitals between 2017 and 2022.
Results SI, PP and ROX values divided patients into eight mutually exclusive physiologic categories. Mortality was highest in patient-categories that included a ROX index <22, and a ROX <22 multiplied the risk of any other abnormality. Patients with a ROX <22, PP <42 mmHg and SI >0.7 had the highest mortality and accounted for 40% of deaths within 24-hours of admission, whereas patients with a PP ≥42 mmHg, SI ≤0.7 and ROX ≥22 had the lowest risk of death. These results were the same in both the Canadian and Dutch patient cohorts.
Conclusion SI, PP and ROX values can place acutely ill medical patients into eight mutually exclusive pathophysiologic categories with different mortality rates. Future studies will assess the interventions needed by these categories and their value in guiding treatment and disposition decisions.