Using photoplethysmography data to estimate heart rate variability and its association with organ dysfunction in pediatric oncology patients

Figures

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  Fig. 1. Bland-Altman plot and time series example. Bland-Altman plot (a) showing the agreement between mean hourly PRVi and mean hourly HRVi when both measurements were available in this cohort of patients. The limits of agreement, depicted as dashed lines above and below the middle line, were calculated as mean of difference ± 1.96*s, where s is the standard deviation of the difference. Time series (b) of a patient transferred to the pediatric intensive care unit (PICU) who required mechanical ventilation. The red lines represent the integer pulse rate variability (PRVi). Gaps in the PRVi represent times when the patient was not connected to a PPG sensor. The daily pSOFA score is shown using the dark grey line. Days in the PICU (orange) and on mechanical ventilation (yellow) are shown in the horizontal axis. The patient has a drop in PRVi starting on day 7, which precedes a transfer to the PICU on day 11 and an increase in the pSOFA score. The PRVi reaches its lowest point on days 11 and 12 preceding the initiation of mechanical ventilation