Background - In the recent wars, 77% of all British casualties received extremity injuries. The critical nature of these injuries resulted in amputations to preserve life, when the limb itself was potentially salvageable. In response, the present research has focussed on development of new technology to reduce amputations by preserving tissue viability. Materials and Methods - Novel technology was developed including; a dual-bladder pneumatic tourniquet; a cooling sock to reduce tissue temperature; and a perfusion support system to perfuse the limb independently of systemic circulation in hospital. Testing involved laboratory protocols, mimetic of the combat setting. The cooling sock and limb support system were tested using disarticulated porcine and ovine limbs. Techniques were employed to assess the impact of these technologies, including implanted thermistors, doppler flow, infrared scanning and neural stimulation. In ovine limbs histology and blood gas analysis was also studied Results - Topical CO2 cooling was associated with deep cooling similar to ice packing, so was utilised while transporting disarticulated porcine limbs reducing deep tissue temperature by between 7.26-15.88oC. The limbs underwent neural stimulation to assess muscle contraction, showing twitch at procedure termination in 2 of the 3 intervention limbs but none of the control limbs. This work was repeated using disarticulated ovine limbs. There were 4 arms in this element; cooled - perfused, non-cooled - perfused, cooled - non-perfused and non-cooled - non-perfused. Deep tissue temperature reduction was very similar between the cooled and non-cooled tests (5.86±3.34oC and 5.23±0.28oC respectively). Baseline nerve stimulation showed that contraction was present in all limbs, however, at the end, contraction was detected only in perfused limbs. Discussion and Conclusions - Overall, these studies demonstrate that the benefit of cooling was less than expected, but, perfusing the limbs preserved tissue viability. The limb stabilisation technology has a clear tissue preserving effect and offers promise as a technology that can be of benefit to personnel injured in austere situations.
|Date of Award||28 Jan 2021|
- University Of Strathclyde
|Sponsors||EPSRC (Engineering and Physical Sciences Research Council)|
|Supervisor||Terry Gourlay (Supervisor), Mary Grant (Supervisor) & Craig Robertson (Supervisor)|