Continuous peripheral perfusion index in patients admitted to hospital wards - An observational study.

INTRODUCTION: Risk patients admitted to hospital wards may quickly develop haemodynamic deterioration and early recognition has high priority to allow preventive intervention. The peripheral perfusion index (PPI) may be an indicator of circulatory distress by assessing peripheral perfusion non-invasively from photoplethysmography. We aimed to describe the characteristics of PPI in hospitalized patients since this is not well-studied. MATERIALS AND METHODS: Patients admitted due to either acute exacerbation of chronic obstructive pulmonary disease (AECOPD) or after major abdominal cancer surgery were included in this study. Patients were monitored continuously up to 96 hours with a pulse oximeter. Comparisons between median PPI each day, time of day and admission type were described with mean difference (MD) and were analysed using Wilcoxon rank sum test and related to morbidity and mortality. RESULTS: PPI data from 291 patients were recorded for a total of 9279 hours. Median PPI fell from 1.4 (inter quartile range, IQR 0.9-2.3) on day 1 to 1.0 (IQR 0.6-1.6) on day 4. Significant differences occurred between PPI day vs evening (MD = 0.18, 95% CI 0.16-0.20, P = .028), day vs night (MD = 0.56, 95% CI 0.49-0.62, P < .0001) and evening vs night (MD = 0.38, 95% CI 0.33-0.42, P = .002). No significant difference in median PPI between AECOPD and surgical patients was found (MD = 0.15, 95% CI -0.08-0.38, P = .62). CONCLUSION: Lower PPI during daytime vs evening and night-time were seen for both populations. The highest frequency of serious adverse events and mortality was seen among patients with low median PPI. The clinical impact of PPI monitoring needs further confirmation.

Physiological abnormalities in patients admitted with acute exacerbation of COPD: an observational study with continuous monitoring.

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) may rapidly require intensive care treatment. Evaluation of vital signs is necessary to detect physiological abnormalities (micro events), but patients may deteriorate between measurements. We aimed to assess if continuous monitoring of vital signs in patients admitted with AECOPD detects micro events more often than routine ward rounds. In this observational pilot study (NCT03467815), 30 adult patients admitted with AECOPD were included. Patients were continuously monitored with peripheral oxygen saturation (SpO2), heart rate, and respiratory rate during the first 4 days after admission. Hypoxaemic events were defined as decreased SpO2 for at least 60 s. Non-invasive blood pressure was also measured every 15-60 min. Clinical ward staff measured vital signs as part of Early Warning Score (EWS). Data were analysed using Fisher's exact test or Wilcoxon rank sum test. Continuous monitoring detected episodes of SpO2 < 92% in 97% versus 43% detected by conventional EWS (p < 0.0001). Events of SpO2 < 88% was detected in 90% with continuous monitoring compared with 13% with EWS (p < 0.0001). Sixty-three percent of patients had episodes of SpO2 < 80% recorded by continuous monitoring and 17% had events lasting longer than 10 min. No events of SpO2 < 80% was detected by EWS. Micro events of tachycardia, tachypnoea, and bradypnoea were also more frequently detected by continuous monitoring (p < 0.02 for all). Moderate and severe episodes of desaturation and other cardiopulmonary micro events during hospitalization for AECOPD are common and most often not detected by EWS.