# Cerebral Hemodynamics Measured by Wearable Near-Infrared Spectroscopy During Bedside Mobilization in a Patient With Chronic Heart Failure Hospitalized for Acute Exacerbation

## TL;DR

This study used wearable NIRS to monitor brain blood flow in a heart failure patient during hospital stays, showing how cerebral oxygen levels change with posture and recovery.

## Contribution

The study demonstrates the potential of wearable NIRS for real-time monitoring of cerebral hemodynamics in heart failure patients.

## Key findings

- Oxyhemoglobin and cerebral oxygen saturation were lowest in the standing position during both NIRS measurements.
- The first admission showed greater variability in cerebral oxygen levels and more pronounced orthostatic hypotension symptoms.
- NIRS data reflected changes in blood pressure, OH severity, and cerebral autoregulation influenced by weight loss progression.

## Abstract

This report aimed to investigate the relationship between cerebral hemodynamics and orthostatic hypotension (OH) in a patient with acute exacerbation of chronic heart failure (HF) by measuring oxyhemoglobin (O2Hb) and regional cerebral oxygen saturation (rSO2) using the wearable near-infrared spectroscopy (NIRS) device for risk management. A 61-year-old man was diagnosed with acute exacerbation of chronic HF. The patient was admitted to the hospital for the first time on day 0, and the first NIRS was performed on day 9. He was discharged on day 30 but was admitted for the second time on day 86, and the second NIRS was performed on day 100.

Although HF symptoms, including weight gain, cardiomegaly, and pleural effusion, present at both admissions had improved at the time of NIRS measurements, there was a difference between the first and second admissions in diuresis, progression of diuresis-related weight loss, and OH symptoms. Specifically, weight loss progressed more rapidly during the first admission, with lower body weight at the time of the first NIRS measurement. Near-infrared spectroscopy assessments were conducted in the following sequence: supine, 30° head-up, sitting, standing, sitting, and supine again. During the first measurement, blood pressure decreased in the sitting and standing positions, heart rate increased only in the standing position, and the patient reported dizziness in both positions. At the second admission, blood pressure and heart rate fluctuated less, and there were no subjective symptoms. Oxyhemoglobin and rSO2 were lowest in the standing position in both measurements. However, compared with the second measurement, the first measurement showed greater variability in O2Hb and rSO2 and lower values in all positions except supine. These findings suggest that NIRS data may reflect changes in blood pressure, OH multiple variants, OH severity, and cerebral autoregulation. Additionally, they may be influenced by various factors, including differences in the progression of weight loss between the two hospitalizations.

Therefore, this study demonstrates the potential of wearable NIRS technology to transform patient care by providing real-time, actionable insights into cerebral hemodynamics. However, further research is required to confirm the generalizability of these findings.