Can Eyemasks Reduce Neonatal Stress Following Dilated Retinal Examination?

Abstract

Purpose : Dilated retinal examination is routinely performed for neonates at risk of
retinopathy of prematurity (ROP). While these examinations help prevent blindness,
they are physiologically stressful for infants; changes in oxygen saturation, blood
pressure and heart rate occur during the exam and increased apneic episodes 24-48hrs afterward. We postulate that photosensitivity during mydriasis contributes to exam stress and reducing light stimulation with a phototherapy mask will reduce stress.

Methods : Multi-centre randomized clinical study. Infants with a birthweight <1500g or
gestational age ≤32 weeks scheduled for their first ROP screening were randomized to receive routine care or a phototherapy mask during mydriasis in addition to routine care, worn for a minimum of 4hrs. Retinal exams were performed by staff surgeons and fellows. The primary outcome was the frequency of any desaturation, bradycardic event, or apneic event 12 hours following the examination compared to baseline. Heart rate, respiratory rate and oxygen saturation were also recorded for 4 hours following the examination.

Results : A total of 51 infants were examined: 28 in the masked group; 23 in the control
group. 10 and 13 infants were on ventilator support at the time of examination in each group, respectively. There was a 57.7% decrease in all stressful events in the masked group compared to control in the 12 hour post-exam period (Rate Ratio=0.42, 95% CI 0.2-0.9, P=0.024). There was a 61.3% decrease in bradycardic events in the masked group compared to control (RR=0.39, 95% CI 0.2-1.0, P=0.042). Heart rate was higher in both groups after the exam (Mean HR: 165 bpm post vs 157 bpm pre; P=0.04), with no difference in between groups (Effect by group P=0.31). There was no significant difference seen in either group in respiratory rate or oxygen saturation at 2 or 4 hours after the exam. Risk factors associated with increased stress included younger gestational age (RR=1.32 95%CI [1.2-1.5] per week), lower birthweight (RR=1.39 [1.2-1.5] per 100g), ventilator support around the time of exam (RR=2.67 [1.3-5.6]), intraventricular hemorrhage (RR=3.78 [1.9-7.3]), and hyponatremia (RR=3.42 [1.8-6.6]). No adverse events occurred while using eye masks.

Conclusions : Neonates who wore a phototherapy mask during pupillary dilation had lower rates of stressful episodes following dilated retinal examination, particularly lower episodes of bradycardia.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.