Expert comments

Comments on this technology were invited from relevant patient organisations and clinical experts working in the field. The comments received are individual opinions and do not represent NICE's view.

All 3 experts were familiar with and had used this technology before.

Level of innovation

All experts said that the NPi-200 is innovative compared with a pen torch. The technology is innovative because it offers an objective measure of pupil size and response and potential trends in intracranial pressure. One expert said that the metric can be compared against previous readings done by different professionals, reducing inter- and intra-observer variability. Experts were not aware of any other competing or alternative technologies available to the NHS.

Potential patient impact

All experts said that using NPi-200 provides an objective, standardised and accurate measure of pupil size and reactivity. Two experts also said that it has the potential to speed up the identification of patient deterioration and provide early intervention to neurological emergency. Experts noted that NPi-200 would be of benefit to people with acute brain injury or neurological impairment. Another expert said that NPi-200 has the potential to improve outcomes in people with raised intracranial pressure and brain trauma. Finally, 1 expert said that the use of the NPi-200 has the potential to improve outcomes by identifying changes in a person's clinical condition that otherwise could have been missed.

One expert said that 20% of intensive treatment unit (ITU) admissions had their neurological pupil index (NPi) measurements taken at some point during their admission. Another expert noted that NPi can be used for 550 to 600 patients per annum in their intensive care unit.

Potential system impact

Two experts noted that NPi-200 will cost more than the relatively inexpensive pen torch. Two experts do not expect an impact on the number of staff, or a reduction in other equipment needed as nurses will still carry a pen torch for other reasons. One expert said that NPi-200 has the potential to reduce overall cost across the whole pathway through a potential reduction in CT scanning and a reduced length of stay. It may also lead to earlier decisions to carry out brainstem testing and potentially improve the possibility of organ donation. Two experts expect a quicker response to changes in pupil size and reactivity and reduced inter-observer variability. Early intervention in raised intracranial pressure may improve functional outcomes. One expert also said that this may lead to changes in patient management. One expert noted that the use of NPi-200 has changed clinical management in their ITU regarding the decision to perform CT scans, earlier brainstem testing, and changes in medical management such as increasing target mean arterial pressure in response to a decrease in NPi.

All experts said that a short training session of about 30 minutes is needed for staff. None of the experts were aware of any safety concerns surrounding this technology.

General comments

One expert said that they use NPi-200 regularly and that it is particularly useful for people who are unconscious or paralysed. However, it can be difficult to use in small infants who are not paralysed. Another expert said that nursing staff felt that the objective nature of the NPi-200 takes away a burden of responsibility when assessing pupils, which they know may influence patient management. Nursing staff also felt that more than 1 NPi-200 device is needed per unit.

Two experts noted that NPi-200 would be in addition to current standard care, while 1 expert said that NPi-200 has the potential to replace current standard care. No barriers to adoption have been identified by the experts, apart from 1 expert noting the cost could be an obstacle.

One expert said that NPi-200 has the potential to provide a reproducible metric that can be used to monitor depth of sedation, progression of illness or presence of raised intracranial pressure. Even though the evidence does not appear to address this, the benefits remain possible.

Two experts said that further research is needed to address the uncertainty in the evidence base, including research in children and research on intracranial pressure. One expert expressed the need for high quality randomised controlled trials to demonstrate clinically relevant benefits to support investment in the technology.