PUMA technical objectives

PUMA project aims to develop a novel portable and non-invasive system to prevent and early detect the risk of Pressure Ulcer (PU) development and revert its onset at Tetraplegic Spinal Cord Injured (T-SCI) individuals relying on wheelchairs, based on the control and improvement of tissue viability.

Overall outcomes/objectives of PUMA are as follows:

Scientific Objectives

  • Objective 1: Determine the safety thresholds of buttock tissue status (blood flow, blood oxygenation, temperature, humidity and pressure) and repositioning movements (frequency, duration, involved zones) of healthy users sitting in a chair.

  • Objective 2: Determine the FES patterns (pulse frequency, duration and amplitude) and the time of stimulation session to a) increase blood flow when pressure is applied, and b) improve baseline state of muscular- vascular systems; in both cases, without provoking discomfort neither fatigue on SCI persons.

  • Objective 3: Determine a) the baseline status of buttock tissue of SCI persons; b) SCI physiological response to applied pressures (0-40 mmHg; 40-65 mmHg; 65-85 mmHg) during several intervals (1-5 minutes;5-20 minutes; > 30 minutes); and c) SCI intrapersonal variables (body mass index, gender, etc.) that affect to baseline and response.

  • Objective 4: Select the optimal sensor to measure tissue viability based on the following parameters: robustness, reliability, range, resolution, cost, embedding difficult and power consume.

Technical Objectives

  • Objective 1: Develop a sensor matrix (number of sensors, distance and distribution in zones depending on PU risk as ischios) to detect PU risk in a robustness and reliability way.
  • Objective 2: Develop a FES system with stimulation ranges (pulse frequency, duration and amplitude) that cover heterogeneity of SCI persons (e.g. sensitivity).
  • Objective 3: Embed sensors and FES on washable smart underwear textile to ensure electrodes contact and patient comfort.
  • Objective 4: Develop a dynamic cushion of with at lest 3 independent zones distributed according to zone risk (e.g. ischios).
  • Objective 5: Develop an intelligent control system to optimal use and combine FES and repositioning (cushion and TILT) strategies in function of sensors output and user / context characteristics (outside/inside, working/leisure resting).
  • Objective 6: Integrate HealthySkin solution on an electrical wheelchair to allow SCI persons sitting without risk during a whole day.
  • Objective 7: Validate the usefulness and effectiveness of HealthySkin prototype with 20 SCI persons using it during 2 hours and 10 SCI persons using it during 1 week.