Neurological pupil index

is obtained using a pupillometer, and the measurement is compared against a normative model of pupil reaction to light and automatically graded by the NPi on a scale of 0 to 4.9.

These indices have been studied in various contexts, including the assessment of comatose patients following cardiac arrest (CA) and the evaluation of traumatic brain injury (TBI).

The study concluded that both indices are interchangeable for assessing neurological outcomes in CA patients, further supporting their reliability in clinical practice.

This study demonstrated that QPi and NPi provide strongly correlated results when used to monitor pupillary reactivity, reinforcing their role as reliable tools for early decision-making in neurocritical care.

Together, these studies reinforce the equivalence and utility of QPi and NPi as interchangeable tools in critical care, particularly for monitoring pupillary reactivity and predicting neurological outcomes in patients with acute brain injuries or post-cardiac arrest comas.