Posture Detection for Automated Abdominal Binder
Condition: Hypotension, Orthostatic
MeSH terms: Hypotension, Orthostatic; Hypotension
Study type: Observational

Summary: 
      The automated inflatable abdominal binder is an investigational device for the treatment of
      orthostatic hypotension (low blood pressure on standing) in autonomic failure patients. The
      purpose of this study is to evaluate the performance of the binder in detecting body posture
      during different types of human motion patterns and activities of daily living, and to
      develop new (and better) ways to detect upright posture. In particular, the investigators
      want to determine if activities of daily living, normally encountered by patients (lying
      down, sitting, standing, walking, and climbing up and down steps), interfere with the
      detection of upright posture used to trigger the device. Studies will be conducted in healthy
      subjects because the main purpose of this study is to evaluate posture detection rather than
      treating orthostatic hypotension.
    

Detailed description: 
      The Primary Objective of this study is to develop and validate the algorithm needed to detect
      upright posture with a waist 3-axis accelerometer. A Secondary Objective is to determine the
      performance reliability of posture detection of the thigh and waist accelerometers when
      exposed to activities of daily living (standing, walking, climbing stairs). We will test the
      primary and secondary objectives in normal subjects using a single study design. Studies for
      both objectives will be conducted simultaneously on each subject on a single study day.
      Normal subjects will wear a device with the waist accelerometer incorporated within the
      controller box.

      Subjects will be instrumented with the abdominal belt and controller box containing the waist
      accelerometer sensor. The external accelerometer sensor will be fixed with a Velcro around
      the thigh. In addition, subjects will wear two commercially available accelerometer sensors:
      1) the ActivPal on the thigh of the other leg, and 2) an external accelerometer attached to
      the back of the belt at the level of the waist. The ActivPal can detect the upright posture
      but cannot distinguish between supine and sitting. The sensor placed on the back will be less
      affected by belly size in case of obese subjects. Both sensors will be used as a reference
      and for comparison. We will record all accelerometer signals during different body positions
      and activities. The activities will include lying down, sitting, getting up and standing
      still, walking, and climbing up and down steps for about one minute each for a total of 15-20
      minutes per group of activities. Participants will perform 3 groups of activities. The order
      of activities within each group will be randomized. We might also ask you to perform ~3 small
      jumps to synchronize the sensors at the beginning, middle and the end of each set of
      activities.
    

Intervention name(s): Automated abdominal binder
Intervention type(s): Device
Intervention description(s): Inflatable abdominal binder
Observational model: Cohort
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Healthy volunteers
      
Keywords: posture detection; healthy subjects