The Reliability Assessment of Emergency Paramedics' Fatigue Using Automated Pupillometry

The dynamic changes of PLR were measured using the PLR-3000 pupillometer (NeurOptics, CA, USA), a hand-held portable device. Determination of PLR with automated pupillometry can be performed with a rubber cup covering the measured eye and the subject's hand covering the non-measured eye. A flash of visible white light with a duration of 0.8 sec and a pulse intensity of 50 µW is delivered to induce a pupillary reflex, and repeated video images at more than 30 frames/sec are stored for 6.65 sec. The device provided the examiner with maximum and minimum pupil size (Init and End), constriction percentage (%PLR), latency (LAT), constriction and dilation velocity (CV and DV), and T75.