Repeated measurements of ERGs and VEPs using chloral hydrate sedation and propofol anesthesia in young children

摘要

Purpose Sedation with chloral hydrate or anesthesia using propofol allow ocular examination and testing in young children, but these drugs may affect electrophysiologic recordings. We compared the flash and pattern ERGs and VEPs recorded with each drug in a cohort of young children enrolled in a prospective study of optic nerve hypoplasia (ONH) syndrome. Methods ERGs and VEPs to light-adapted, standard, full-field flashes, to standard and steady-state pattern-reversal (PR) were recorded with cycloplegia in 9 participants. Age range at the first session, with chloral hydrate was 8-23 mo; at the second session with propofol it was 20-29 mo. Examiners masked to the drug and clinical conditions measured the waveforms for longitudinal, paired comparisons between the sessions. Results Flash ERG amplitudes did not differ between sessions; peak times were longer at the second session (propofol) by clinically insignificant amounts ( 10 mo between sessions (n = 5, 10 eyes) but not for those with a shorter inter-test interval ( 0.05, n = 4). Magnitudes of the steady-state PERGs did not differ between tests but the waveforms had earlier peaks at the second test with propofol. Flash VEP waveforms were present in 10/18 eyes and showed 72 agreement for recordability between sessions. Standard pattern VEPs were recordable in only a few eyes in this cohort with ONH. Conclusions Light-adapted flash ERG waveforms were generally similar with chloral hydrate and with propofol. Larger PERGs with later peaks, found in the second session (propofol) could reflect maturation of the PERG generators, as the differences found were associated with a greater age difference between the sessions, but we do not rule out that small differences in the waveforms may be drug-related. There are insufficient VEP data from these children with ONH to identify drug-related or maturational effects on VEPs.