Efficiency and safety of phenylephrine and tropicamide used in premature retinopathy: a prospective observational study

Abstract

BackgroundTo determine effects and side effects of topical application of phenylephrine 2.5% and tropicamide 0.5% combination in preterm infants.MethodsIn this prospective observational study, 60 infants undergoing retinopathy of prematurity (ROP) screening were prospectively observed. Pupillary diameter, blood pressure, heart rate, and oxygen saturation were monitored before and after up to 24 h during ROP screening examinations.ResultsThe mean pupillary diameter 1 h after the instillation of drops was 5.58 ± 0.75 mm for both eyes. The mean systolic and diastolic pressure and oxygen saturation of infants did not change statistically until the end of the study. The average heart rate decreased by a mean of 4.96 beats/minute from the baseline following eye drops instillation. General condition deterioration, fall in oxygen saturation and bradycardia were observed in 4 infants that already had respiratory distress syndrome.ConclusionThe phenylephrine 2.5% plus tropicamide 0.5% drop is effective and safe as mydriatic combination for retinopathy of prematurity screening. In infants with an additional systemic disease such as respiratory distress syndrome, the side effects of mydriatic drops may be more common. Such babies should be kept under close observation.Trial registrationThe trial was retrospectively registered on 28 February 2018. The ClinicalTrials.gov Identifier is NCT03448640.

Early Hemodynamic Effects of Mydriatic Eye Drops in Preterm Infants

“…Five types of muscarinic receptors are present in various organs like the central nervous system (cortex, substantia nigra, hippocampus, and brain stem), heart, smooth muscle, and eyes. Therefore, even though tropicamide is accepted as a safe drug, it can cause systemic adverse effects like myasthenia-like syndrome [3,7,17,18]. There was no change in the cerebral oxygenation levels in preterm infants in the early period in our study.…”

“…However, these drugs may cause systemic adverse effects in case of systemic absorption. Phenylephrine is a selective α-adrenergic receptor agonist and potent vasoconstrictor that cause increased blood pressure, systemic vascular resistance, and reflex bradycardia in parenteral administration [3,8]. On the other hand, tropicamide is a short-acting atropine-like anticholinergic drug with a parasympatholytic effect on pupillary muscles.…”

“…Alpay et al found a significant drop in heart rate after mydriatic drop instillation but no change in blood pressure [3]. While many studies report increment in the heart after mydriatic drops, Bolt et al had found no significant change with the same combination of %2.5 phenylephrine and %0.5 tropicamide [21] .…”

“…Considering that around 23.000 infants are born at less than 32 gestational weeks each year, according to the Turkish Ministry of Health and Public Health Institute of Turkey (unpublished data, 2015), it can be assumed that at least 100.000 ROP examinations have been performed in Turkey annually. Hence, it is crucial to know the adverse effects of eye drops used during examinations and ROP examination itself, which are frequently performed [3].…”

Tropicamide and anaphylaxis

“…Alpay et al . [ 8 ] recommended 0.5% dose of tropicamide combine with phenylephrine (2.5%) in infants.…”