[Influence of Propofol and Remifentanil on Pupillary Light Reflex Assessed by a Hand-held Point-and-shoot Pupillometer].

Background: Anisocoria and abnormality of pupil- lary light reflex may indicate sight-threatening or life- threatening neurological injury. Many perioperative patients are given opioids for analgesia, and opioids produce miosis and make it hard to assess anisocoria or pupillary light reflex. This study was designed to determine the influence of induction of anesthesia on pupillary light reflex assessed by a hand-held point- and-shoot pupillometer.

Methods: Eighteen patients receiving general anes- thesia were enrolled. Anesthesia was inducted by remifentanil, propofol and rocuronium after' pre-oxy- genation and tracheal intubation or insertion of supra- glottic airway device. The pupillary measurement data before induction and after intubation or insertion of supraglottic airway device were taken from records.

Results: With eighteen patients, thirty six eye data were compared. After intravenous injection of propofol and remifentanil infusion, pupils were constricted from 4.0±1.1 mm to 1.8±0.4 mm, and average constriction velocity (CV), neurological pupil index (NPI) measured automatically from light reflex decreased for 2.5±0.9 mm, sec⁻¹ to 0.3±0.2 mm · sec⁻¹, 4.4±0.4 to 3.9±0.4, respectively (P<0.0001).

Conclusions: Propofol and remifentanil infusion in- fluence pupillary light reflex and decreases values of NPI and CV. When using these drugs, it is necessary to perform neurologic evaluation using NPI and CV.