Comparison of effects of volatile and intravenous anesthetics on pupillary function during general anesthesia in children: A prospective observational study

Abstract

Background:The light reflex, which reflects central nervous system dysfunction, can also be affected by anesthetic agents. Aims:We evaluated whether these effects differed according to the anesthetic agent in pediatric patients.Methods: Twenty children aged 3-12 years who were scheduled to undergo elective surgery under general anesthesia were randomly allocated to propofol and sevoflurane groups and underwent pupillometric assessments at five points during anesthesia: T1, after confirming loss of consciousness; T2, after endotracheal intubation; T3, at the time of skin incision; T4, 1 h after skin incision; and T5, before endotracheal extubation. The primary outcome was the Neurological Pupil index at T4, and the secondary outcomes were other pupillometric parameters, including pupil diameter, percentage of change in pupil diameter, dilation velocity, and constriction velocity.Results: At T4, the Neurological Pupil index was significantly lower in the sevoflurane group (median difference, 0.30; 95% CI, 0.00 to 0.70; p = .036). Furthermore, the Neurological Pupil index at all time points was lower in the sevoflurane group. The timeand-group interaction effects on constriction velocity and dilation velocity were significantly different [F(1, 4) = 16.68, p = .002; F(1, 4) = 14.78, p = .008, respectively] but were not different on the Neurological Pupil index, pupil diameter, and percentage of change in pupil diameter. No intergroup differences were observed in the baseline characteristics, the flow rate of remifentanil at each time point, and total infused remifentanil. Conclusion:The Neurological Pupil index value in pediatric patients under general anesthesia is affected by the anesthetic agent used; this factor requires consideration in evaluations of the Neurological Pupil index during general anesthesia.

Influence of Sevoflurane on the Neurological Pupil Index in Surgical and Critically Ill Patients: A Pilot Study

“…In patients undergoing surgical procedures, the NPi has been shown to be significantly lower in those anesthetized with sevoflurane or desflurane compared to those receiving propofol within one hour of the surgery’s initiation, regardless of the depth of sedation [ 4 ]. Similar results have been observed in pediatric surgical patients anesthetized with sevoflurane [ 15 ]. These findings may suggest that inhaled anesthetics exert a more pronounced impact on midbrain reflexes than other drugs, although it remains unclear whether the presence of brain damage could further exacerbate these effects.…”

“…Also, inhaled anesthetics have been associated with a lower NPi than propofol in patients undergoing scheduled breast or thyroid surgery, which could suggest different effects of inhaled anesthetics on the alteration of midbrain reflexes when compared to intravenous anesthesia, although the NPi values in the study in question remained within normal ranges [ 4 ]. However, in another study including pediatric surgery, the NPi values were similar under inhaled and intravenous anesthesia [ 15 ]. These findings may be attributed to the concentrations of inhaled sevoflurane or the concomitant administration of other anesthetic and analgesic drugs, which can potentially interfere with pupillary function.…”

Intraoperative neurological pupil index and postoperative delirium and neurologic adverse events after cardiac surgery: an observational study

“…We used propofol and remifentanil as main anesthetics during the study period. In comparison of volatile anesthetics (sevoflurane) and propofol, NPi was well maintained under propofol-based anesthesia compared to sevoflurane throughout the surgery in a small study of pediatric patients undergoing elective surgery 30 . In another small study comparing the effects of anesthetics on NPi, there was no significant change in NPi during surgery in propofol/remifentanil group, while NPi significantly reduced from baseline in sevoflurane, sevoflurane/remifentanil and desflurane/remifentanil groups 31 .…”