Rapid development of a ventilator for use during the COVID-19 pandemic: Clinical, human factor & engineering considerations

The arrival of the COVID-19 pandemic in early 2020 threatened to overwhelm the NH ability to provide sufficient critical care support to patients in the UK. In response to a rapid rise in cases in March 2020, the UK Government issued a call to industry to rapidly design and develop additional ventilators to expand the UK’s capacity for mechanical ventilation. Three NHS consultants working in conjunction with TTP Plc (The Technology Partnership), were at the forefront, evolving the Government brief and developing a safe and effective ventilator, the CoVent™, in less than 5 weeks. The project demonstrates the ability of physicians to guide industry and pool knowledge and resources to rapidly develop and evolve technology in the face of a national emergency. This article discusses key aspects of the design process, highlights the unique human factors and engineering aspects of undertaking this amidst the coronavirus pandemic. Overall we demonstrated that when industry, healthcare and regulatory bodies collaborate and communicate efficiently, huge progress can be made in a fraction of the usual timescales.

Axonal guidance molecules and the failure of axonal regeneration in the adult mammalian spinal cord

A wide variety of molecules are involved as attractive or repulsive guidance cues in the developing nervous system. Some of these molecules are also expressed in the CNS of adult mammals where, following injury, they may repel regenerating axons, inhibit axonal regrowth, or control the behaviour of other cells important for the development of the meningeal and glial scars or the immune response to injury. Ephrins, semaphorins, Slits, Netrins, bone morphogenetic proteins (BMPs) and Wnts are among the most likely molecules to be involved in limiting axonal regeneration in the injured spinal cord. The receptors for these molecules are not universally expressed by neurons but there is evidence that ephrins and semaphorins limit regeneration of particular classes of axon into spinal cord lesion sites. It is likely that other repulsive guidance cues will also differentially affect the regeneration of specific tracts within the spinal cord. In addition to direct effects on axonal regeneration, many axonal guidance molecules have effects on glial, meningeal or immune system cells which also modulate the responses of CNS tissue to injury.