ASSESSING THE VALUE OF INNOVATIVE MEDICAL DEVICES AND DIAGNOSTICS: THE IMPORTANCE OF CLEAR AND RELEVANT CLAIMS OF BENEFIT.

OBJECTIVES: Large numbers of new medical devices and diagnostics are developed and health services need to identify which ones offer real advantages. The National Institute for Health and Care Excellence (NICE) has introduced a system for assessing technologies that are often notified by companies, based on claims made for their benefits to patients, the National Health Service, and the environment. METHODS: Detailed scrutiny of claims made for the benefits of products and the corresponding evidence, seeking associations between these and the selection of products for full evaluation to produce NICE guidance. RESULTS: Between 2009 and 2015 a NICE committee considered 169 technologies, of which it selected 74 (44 percent) for full evaluation, based on the claims of benefit and the evidence available. An average of 7.5 claims were made per technology; the total number did not influence selection but presence of studies supporting all the claims (p < .001) or any of the claims (p < .05) had a positive influence, as did claims for quicker patient recovery (p < .001). A greater number of studies to support the claims made selection more likely (p < .001), as did cohort studies (p < .05) and surveys (p < .05) but, unexpectedly, not randomized trials. The Medical Device Directive class had no influence. CONCLUSIONS: This study presents categories of claims that may be useful to those developing new products and to others engaged in health technology assessment. It illustrates the importance of relevant evidence and of having a clear vision of the place of new products in care pathways from an early stage.

A portable instrument for high-speed brain function imaging: FEITER.

Electrical Impedance Tomography (EIT) can resolve dynamic physiological information deep within human subjects [1], but its sensitivity is challenged in the case of imaging the head [2]. Here, we report a new system called fEITER that has been designed and built to enable functional imaging of the human brain using EIT via scalp-mounted electrodes, integrated with stimulation of evoked responses. Using Field-Programmable Gate Array (FPGA) technology, it provides excellent flexibility in terms of current-pattern excitation and signal processing. The instrument operates at 100 frames/second (fps) with noise of 1 µV on the rms voltage measurements. Clinical trials have been authorized by the UK MHRA and example data from human subjects are presented.

Delta sleep-inducing peptide alters bispectral index, the electroencephalogram and heart rate variability when used as an adjunct to isoflurane anaesthesia.

BACKGROUND AND OBJECTIVE: Delta sleep-inducing peptide (DSIP) is an endogenous peptide that crosses the blood-brain barrier, named after its association with natural sleep and enhanced electroencephalogram (EEG) delta rhythm. The objective of this study was to determine whether DSIP could be used as an adjunct to volatile anaesthesia in humans, our hypothesis being that DSIP is a natural hypnotic that would increase anaesthetic depth. The aims were to assess depth of anaesthesia using bispectral index (BIS), the EEG and heart rate variability (HRV), and to determine whether DSIP altered the symmetry of EEG between the left and right cerebral hemispheres. METHODS: Twenty-four female ASA I or II patients gave written, informed consent to a protocol approved by our local research ethics committee. Twelve were randomly assigned as controls to receive saline. The other 12 were randomly allocated to receive one of three intravenous bolus doses of DSIP (Clinalfa) at 25, 50 or 100 nmol kg(-1). The first administration of DSIP was while awake and the second after induction of anaesthesia with propofol and maintenance with isoflurane. BIS and EEG parameters were measured continuously using a bilateral electrode montage. RESULTS: DSIP significantly increased heart rate, decreased HRV and, paradoxically, significantly reduced delta rhythm along with reducing burst suppression and increasing BIS at 25 nmol kg(-1) during isoflurane anaesthesia. DSIP also significantly altered bilateral symmetry of EEG. CONCLUSION: DSIP probably reduced parasympathetic tone and decreased (lightened) the depth of anaesthesia measured using BIS.

The vagus nerve as a conduit for neuroinvasion, a diagnostic tool, and a therapeutic pathway for transmissible spongiform encephalopathies, including variant Creutzfeld Jacob disease.

It is hypothesised that the vagus nerve (cranial nerve X) is an important conduit for infective neuroinvasion during the incubation of certain transmissible spongiform encephalopathies (TSEs) including scrapie in sheep, variant Creutzfeld Jacob disease in humans, chronic wasting disease in deer, and bovine spongiform encephalopathy in cattle. Presence of infection in the brainstem will disrupt normal function of this important region responsible for autonomic control of visceral function via the vagus nerve. It is proposed that physiological study of disrupted vagal function using techniques such as heart rate variability will indicate early, and ongoing, functional signs of infection even before levels of abnormal prion protein reach the thresholds currently used in tests for the presence of TSEs. It is further suggested that repeated measures of vagal function during treatment with experimental therapies will give a non-invasive, repeated measures index of drug efficacy. In addition, pharmaceutical interventions directed via the vagus nerve will bypass the blood brain barrier and take an anatomical route appropriate to the treatment of TSEs.