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A flexible and low power telemetric sensing and monitoring system for chronic wound diagnostics.

Mehmood N, Hariz A, Templeton S, Voelcker NH - Biomed Eng Online (2015)

Bottom Line: The performance of the whole telemetric sensing system is validated on a mannequin leg using commercial compression bandages and dressings.Effective range of data transmission is 4-5 m in an open environment.Pre-clinical results on a healthy human subject suggest its clinical usability and value to health practitioners.

View Article: PubMed Central - PubMed

Affiliation: School of Engineering, University of South Australia, Adelaide, SA, , 5001, , Australia. nasir.mehmood@unisa.edu.au.

ABSTRACT

Background: Non-healing chronic wounds, such as venous leg ulcers, can be monitored non-invasively by using modern sensing devices and wireless technologies. The development of such a wireless diagnostic tool may improve chronic wound management by providing evidence on efficacy of treatments being provided. This paper presents a low-power portable telemetric system for wound condition sensing and monitoring. The system aims at measuring and transmitting real-time information of wound-site temperature, sub-bandage pressure and moisture level from within the wound dressing.

Methods: Commercially available non-invasive temperature, moisture, and pressure sensors are interfaced with a telemetry device on a flexible 0.15 mm thick printed circuit material to construct a light-weight, non-invasive, biocompatible, and low-power sensing device. The real-time data obtained is transmitted wirelessly to a portable receiver which displays the measured values. The performance of the whole telemetric sensing system is validated on a mannequin leg using commercial compression bandages and dressings. A number of trials on a healthy human volunteer are performed where treatment conditions were emulated using various compression bandage configurations.

Results: A reliable and repeatable performance of the system is achieved under compression bandage and with minimal discomfort to the volunteer. The system is capable of reporting instantaneous changes in bandage pressure, moisture level and local temperature at wound site with average measurement resolutions of 0.5 mmHg, 3.0% RH, and 0.2°C respectively. Effective range of data transmission is 4-5 m in an open environment.

Conclusions: A flexible and non-invasive sensing system is developed to acquire and wirelessly transmit wound parameters from within a compression bandage and wound dressing worn on a human limb. Pre-clinical results on a healthy human subject suggest its clinical usability and value to health practitioners. However, further performance evaluations of the device on a wider population of healthy human subjects and on patients with chronic wounds are required to confirm its medial usefulness and to quantify its real impact on chronic wound management.

No MeSH data available.


Related in: MedlinePlus

Sensing system under a 4-layer compression bandage. (a) Allevyn™ dressing with micro-volume extension set in place prior to application. (b) Dressing and sensors in place on leg prior to bandage application. (c) Bandaging in place immediately following application. (d) Dressing and sensors in place immediately following removal of bandages.
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Fig5: Sensing system under a 4-layer compression bandage. (a) Allevyn™ dressing with micro-volume extension set in place prior to application. (b) Dressing and sensors in place on leg prior to bandage application. (c) Bandaging in place immediately following application. (d) Dressing and sensors in place immediately following removal of bandages.

Mentions: In this trial, a 4-layer bandage system known to apply 40 mmHg at ankle was used. Bandages were applied as per manufacturer’s instructions. A small slit was made in the outermost cohesive bandage (layer 4) to allow battery connection. Allevyn™ Adhesive (Smith & Nephew) 12.5 cm™ 12.5 cm dressing was applied to the lower calf and a small cut was made in the back of the dressing (Figure 5(a)). A micro-volume extension set tubing was attached to the dressing and the slit sealed with film tape to allow injection of fluid (As genuine wound fluid was not available soy sauce diluted with water was used). The fluid was injected under the dressing to mimic wound exudate and soy sauce was chosen so that the spread of fluid was visible during experiments. The sensing system was then attached to the lower leg (Figure 5(b)). The pressure sensor was placed proximal to the medial malleolus between exposed skin and bandages. The moisture sensor was placed at the bottom corner of the Allevyn™ dressing between the exposed skin and the dressing. The results of second trial are plotted in Figure 6. The average value of temperature during this trial was 33 ± 1°C. The moisture values were increasing gradually as more fluid was injected to the dressing until the sensor was soaked with the fluid, the point from where the readings started rising up (readings 21–24 in Figure 6(a)). The sub-bandage pressure values (Figure 6(b)) were dependent on posture, being higher during walking and standing and lower during sitting or lying. It can also be observed from the graph that the pressure readings were consistently dropping over time. This phenomenon can be attributed to loosening of bandage layers with movement.Figure 5


A flexible and low power telemetric sensing and monitoring system for chronic wound diagnostics.

Mehmood N, Hariz A, Templeton S, Voelcker NH - Biomed Eng Online (2015)

Sensing system under a 4-layer compression bandage. (a) Allevyn™ dressing with micro-volume extension set in place prior to application. (b) Dressing and sensors in place on leg prior to bandage application. (c) Bandaging in place immediately following application. (d) Dressing and sensors in place immediately following removal of bandages.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4403753&req=5

Fig5: Sensing system under a 4-layer compression bandage. (a) Allevyn™ dressing with micro-volume extension set in place prior to application. (b) Dressing and sensors in place on leg prior to bandage application. (c) Bandaging in place immediately following application. (d) Dressing and sensors in place immediately following removal of bandages.
Mentions: In this trial, a 4-layer bandage system known to apply 40 mmHg at ankle was used. Bandages were applied as per manufacturer’s instructions. A small slit was made in the outermost cohesive bandage (layer 4) to allow battery connection. Allevyn™ Adhesive (Smith & Nephew) 12.5 cm™ 12.5 cm dressing was applied to the lower calf and a small cut was made in the back of the dressing (Figure 5(a)). A micro-volume extension set tubing was attached to the dressing and the slit sealed with film tape to allow injection of fluid (As genuine wound fluid was not available soy sauce diluted with water was used). The fluid was injected under the dressing to mimic wound exudate and soy sauce was chosen so that the spread of fluid was visible during experiments. The sensing system was then attached to the lower leg (Figure 5(b)). The pressure sensor was placed proximal to the medial malleolus between exposed skin and bandages. The moisture sensor was placed at the bottom corner of the Allevyn™ dressing between the exposed skin and the dressing. The results of second trial are plotted in Figure 6. The average value of temperature during this trial was 33 ± 1°C. The moisture values were increasing gradually as more fluid was injected to the dressing until the sensor was soaked with the fluid, the point from where the readings started rising up (readings 21–24 in Figure 6(a)). The sub-bandage pressure values (Figure 6(b)) were dependent on posture, being higher during walking and standing and lower during sitting or lying. It can also be observed from the graph that the pressure readings were consistently dropping over time. This phenomenon can be attributed to loosening of bandage layers with movement.Figure 5

Bottom Line: The performance of the whole telemetric sensing system is validated on a mannequin leg using commercial compression bandages and dressings.Effective range of data transmission is 4-5 m in an open environment.Pre-clinical results on a healthy human subject suggest its clinical usability and value to health practitioners.

View Article: PubMed Central - PubMed

Affiliation: School of Engineering, University of South Australia, Adelaide, SA, , 5001, , Australia. nasir.mehmood@unisa.edu.au.

ABSTRACT

Background: Non-healing chronic wounds, such as venous leg ulcers, can be monitored non-invasively by using modern sensing devices and wireless technologies. The development of such a wireless diagnostic tool may improve chronic wound management by providing evidence on efficacy of treatments being provided. This paper presents a low-power portable telemetric system for wound condition sensing and monitoring. The system aims at measuring and transmitting real-time information of wound-site temperature, sub-bandage pressure and moisture level from within the wound dressing.

Methods: Commercially available non-invasive temperature, moisture, and pressure sensors are interfaced with a telemetry device on a flexible 0.15 mm thick printed circuit material to construct a light-weight, non-invasive, biocompatible, and low-power sensing device. The real-time data obtained is transmitted wirelessly to a portable receiver which displays the measured values. The performance of the whole telemetric sensing system is validated on a mannequin leg using commercial compression bandages and dressings. A number of trials on a healthy human volunteer are performed where treatment conditions were emulated using various compression bandage configurations.

Results: A reliable and repeatable performance of the system is achieved under compression bandage and with minimal discomfort to the volunteer. The system is capable of reporting instantaneous changes in bandage pressure, moisture level and local temperature at wound site with average measurement resolutions of 0.5 mmHg, 3.0% RH, and 0.2°C respectively. Effective range of data transmission is 4-5 m in an open environment.

Conclusions: A flexible and non-invasive sensing system is developed to acquire and wirelessly transmit wound parameters from within a compression bandage and wound dressing worn on a human limb. Pre-clinical results on a healthy human subject suggest its clinical usability and value to health practitioners. However, further performance evaluations of the device on a wider population of healthy human subjects and on patients with chronic wounds are required to confirm its medial usefulness and to quantify its real impact on chronic wound management.

No MeSH data available.


Related in: MedlinePlus