Pain relief during retinopathy screening, nothing works very well.

Mandel R, Ali N, Chen J, Galic IJ, Levesque L: Nitrous oxide analgesia during retinopathy screening: a randomised controlled trial. Arch Dis Child Fetal Neonatal Ed 2012, 97(2):F83-87.

My colleagues and friends Romain Mandel and Nabeel Ali performed a blinded randomized trial of nitrous oxide (laughing gas) for analgesia during routine ophthalmologic eye screening for retinopathy of prematurity. They started the study while I was the chief at the Royal Victoria Hospital in Montreal, and I think the publication downplays what a pain it was to get all the procedures accepted. They had to scavenge the gases because we didn’t want anyone assisting the procedure to be anesthetized (a nurse or ophthalmologist falling over unconscious would have unblinded the trial). Despite what should have been a good administration of a good concentration of N2O, there was no apparent effect on pain responses. I was very happy that Drs Mandel and Ali pursued the trial, despite the difficulties, as I really thought it would work; but unfortunately, even with experienced gentle ophthalmologists, there was no difference in any of the pain indices.

This adds to the literature of things that don’t work very well for the pain responses to ophthalmologic exams. Including sucrose and topical anesthesia.  A recent systematic review noted that these measures are either wholly or relatively ineffective. Kandasamy Y, Smith R, Wright IMR, Hartley L. Pain relief for premature infants during ophthalmology assessment. Journal of American Association for Pediatric Ophthalmology and Strabismus. 2011;15(3):276-80.

On the other hand a humane approach I think should lead to the use of topical anesthetics even if they don’t work very well (until we find something that works better), and the pain scores in the Mandel et al study were lower than other studies, perhaps reflecting the fact that a combined approach with sucrose, topical agents and swaddling the infants was used in both groups. Allowing the baby to suck during the procedure seems to help a little, so a soother or bottle could be added. Maybe the best thing would be change the method of screening, there is some evidence that using a digital fundus camera leads to less tachycardia, (see Mukherjee et al) or, even better, just avoiding the use of a speculum (Mehta et al below).

Mukherjee AN, Watts P, Al-Madfai H, Manoj B, Roberts D: Impact of Retinopathy of Prematurity Screening Examination on Cardiorespiratory Indices: A Comparison of Indirect Ophthalmoscopy and Retcam Imaging. Ophthalmology 2006, 113(9):1547-1552.

Mehta M, Adams GGW, Bunce C, Xing W, Hill M: Pilot study of the systemic effects of three different screening methods used for retinopathy of prematurity. Early Human Development 2005, 81(4):355-360.

About Keith Barrington

I am a neonatologist and clinical researcher at Sainte Justine University Health Center in Montréal
This entry was posted in Neonatal Research and tagged , , . Bookmark the permalink.

1 Response to Pain relief during retinopathy screening, nothing works very well.

  1. Eugene Dempsey says:

    Hi Keith,
    I think the title of this section may be a little misleading. As you point out in the last pargraph, the combination of swaddling, oral sucrose and topical anaesthetic was associated with relatively low scores and I believe should be the standard for ROP screening. Whilst the review you highlight is good, I think the following review is as good

    Pain management during eye examinations for retinopathy of prematurity in preterm infants: a systematic review.Sun X, Lemyre B, Barrowman N, O’Connor M. Acta Paediatr. 2010 Mar;99(3):329-34. Epub 2009 Nov 24. Review.

    Also our own rct of sucrose use (Sweeten, soother and swaddle for retinopathy of prematurity screening: a randomised placebo controlled trial.O’Sullivan A, O’Connor M, Brosnahan D, McCreery K, Dempsey EM. Arch Dis Child Fetal Neonatal Ed. 2010 Nov;95(6):F419-22) showed a reduction in pain scores during speculum insertion and indentation, was not included in Kandasamy review.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.