Cerebral Oxygenation Values in Healthy Adults Volunteers Measured With RheoPatch and NIRO-200NX
Condition: Healthy; Adults
Study type: Observational

Summary: 
      Noninvasive measurement of cerebral tissue oxygen saturation levels by near infrared
      spectroscopy (NIRS) is clinical routine in perioperative medicine. One of the main technical
      challenges of NIRS measurements is to eliminate the influence of signals of the skin and
      skull. A new device (RheoPatch, Luciole Medical AG, Zurich) has been developed by a company
      that also developed an intracranial NIRS probe, which allowed measurements directly in the
      brain and thus improved algorithms for elimination of the extracranial signals. The
      investigators aim to determine baseline values and performance of the new device (RheoPatch)
      compared with a more established NIRS device (NIRO-200NX, Hamamatsu Phototonics, Hamamatsu
      City, Japan)
    

Detailed description: 
      Primary objective is to compare the RheoPatch NIRS device with the NIRO-200NX NIRS device in
      volunteers at rest in supine position. As secondary objectives, repeatability of the
      measurements will be tested with optode reapplications. With measurements in Trendelenburg
      position, the investigators evaluate the influence of body (head) position on the NIRS
      signals.

      Primary outcome are the baseline values of cerebral oxygenation levels measured by RheoPatch
      (SbtO2 (%)) and NIRO-200NX (Tissue oxygenation index: TOI (%)).

      Secondary endpoints are the repeatability of the measurements with sensor reapplications
      (coefficient of repeatability, 5 repeats with each device) and changes of the measurements of
      cerebral oxygenation saturation level in the Trendelenburg position.

      Measurements of baseline cerebral oxygenation values are obtained in supine position with 10
      measurements, alternating between devices. Combined with 5 min measurement phase for
      equilibration and power adjustment, this will require 33 minutes per participant.
    

Intervention name(s): Cerebral oximetry using Rheopatch; Cerebral oximetry using NIRO-200NX
Intervention type(s): Device; Device
Intervention description(s): On the study visit, baseline demographic data (age and gender, BMI) are collected. In supine position the sensor patches (left and right) of the device are applied to the forehead and the cerebral oxymetry values are recorded during 120sec. The sensor patches are then removed and the patches of the second device are applied on the same position on the forehead and the measurement is carried out as described before. For the first measurement of each sensor, a total of 5 minutes equilibration and sensor output power adjustment is allowed. A total of 10 measurements are taken, 5 with each device.
The volunteer is then placed in Trendelenburg position and another 4 measurements are made (2 with each device) as previously described.; On the study visit, baseline demographic data (age and gender, BMI) are collected. In supine position the sensor patches (left and right) of the device are applied to the forehead and the cerebral oxymetry values are recorded during 120sec. The sensor patches are then removed and the patches of the second device are applied on the same position on the forehead and the measurement is carried out as described before. For the first measurement of each sensor, a total of 5 minutes equilibration and sensor output power adjustment is allowed. A total of 10 measurements are taken, 5 with each device.
The volunteer is then placed in Trendelenburg position and another 4 measurements are made (2 with each device) as previously described.
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        The project population consists of volunteers in subjective good health. Volunteers are
        chosen to minimize the effect of diseases on the measurements, as the investigators are
        interested in baseline measurement values and repeatability.