The Pain Response to Mydriatic Eye Drops in Preterm Infants

OBJECTIVE: Evaluate physiologic and behavioral pain responses of premature infants following instillation of mydriatic eye drops for ROP examinations. While burning and stinging occurs in older patients, the infant pain response is not well characterized. STUDY DESIGN: Vital sign and video monitor recorded infant responses before, during, and after mydriatic (tropicamide 1%, phenylephrine 2.5%) administration upon first ROP exam. Two masked observers graded Premature Infant Pain Profile (PIPP) scores immediately prior and following eye drop administration. Scores <7 indicate no/minimal pain, 7-12 slight/moderate, >12 severe. RESULTS: Twenty infants had mean pre-mydriatic PIPP score 3.6 (SD 1.6), mean post-mydriatic score 5.7 (SD 3.4), mean change 2.1 (SD 3.4)(p=0.01). One (5%) had pre-mydriatic PIPP score ≥7, seven (35%) post scores ≥7 (p=0.07) with one >12. CONCLUSIONS: Mydriatic drops cause a clinically significant pain response in one third of infants. Non-pharmacologic supportive measures are recommended for all infants until predictive factors are defined.