Use of a Shear Reduction Surface in Pre-hospital Transport
Condition: Shear Strength
Study type: Interventional

Summary: 
      The purpose of this study was to examine the effectiveness of a shear reduction surface on
      shear, pressure, and comfort used in pre-hospital ground transport.
    

Detailed description: 
      This study enrolled healthy adult volunteers of any race or gender, stratified into 3 Body
      Mass Index (BMI) categories (≤20, 20.1-24.9, ≥25), who served as their own controls. The
      setting for this study was on a closed driving course utilized for training of emergency and
      law enforcement personnel, and the vehicle used was a standard ground ambulance affiliated
      with the Medical Transport of a tertiary medical center.

      Apparatus and/or instruments: A commercial full-length LiquiCell® anti-shear mattress overlay
      (ASMO) (Birchwood Laboratories, Eden Prairie MN) was placed on the standard ambulance
      stretcher mattress. Shear force and tissue interface pressure was measured during a full
      stop, acceleration, travelling at 30 mph, deceleration, and a full stop by a PREDIA device
      (Molten Corporation, Hiroshima Japan) through reusable sensors attached to the sacrum,
      ischial tuberosity, and heel.

      Procedures: Following written informed consent, subjects were weighed and measured with a
      calibrated scale to calculate a current BMI. Three PREDIA sensors were secured to three sites
      (sacrum, ischial tuberosity, and heel) with double-stick tape. Subjects wore standard
      hospital scrub bottoms, and were secured supine to the ambulance stretcher using standard
      procedure. Subjects were blinded to the presence of the LiquiCell® ASMO overlay by a sheet
      covering on the stretcher. The ASMO was placed according to a simple randomization table. The
      stretcher was initially be placed with 0 degree head-of-bed (HOB) elevation, followed by
      subsequent HOB elevations of 15 degrees and 30 degrees. HOB elevations were verified using a
      standard goniometer. The ambulance traveled over a closed course driven by ambulance staff
      members that had passed the mandatory Coaching the Emergency Vehicle Operator (CEVO) driving
      course. The course included at maximum speed of 30 mph and 5 complete stops at each of 3 HOB
      elevations (0, 15, and 30 degrees). Shear measurements (measured in Newtons) and pressure
      measurements (measured in mmHg) for each anatomical site were taken with the PREDIA sensors
      during a full stop, acceleration, travelling at 30 mph, deceleration, and a full stop for
      each "run". At the beginning and completion of each set of 5 runs, subjects were asked to
      rate their discomfort on a scale of 0 (no discomfort) to 10 (worst discomfort imaginable).
      Following the first set of 15 runs, the course was repeated with or without the LiquiCell®
      ASMO according to the randomization table.
    

Intervention name(s): Anti-shear mattress overlay; Standard of Care
Intervention type(s): Device; Other
Intervention description(s): A commercial full-length LiquiCell® anti-shear mattress overlay (ASMO) was placed on the standard ambulance stretcher mattress.; Standard ambulance stretcher mattress
Other intervention name(s): LiquiCell
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Supportive Care
Keywords: pre-hospital transport; shear force; tissue interface pressure