The Eyes have it! Retinopathy of Prematurity updates

A review article in the PNEJM introducing the basic concepts in the pathophysiology and treatment of retinopathy of prematurity (Hartnett ME, Penn JS: Mechanisms and management of retinopathy of prematurity. Prestigious New England Journal of Medicine 2012, 367(26):2515-2526). I think it would be a really good article for a first-year fellow. As usual in the PNEJM review articles, the llustrations are excellent.

Another interesting article is a secondary analysis of data from the multicenter superoxide dismutase trial, in which the principal investigator was Jonathan Davis, you may remember that the original trial (an RCT of intra-tracheal recombinant human SOD in about 300 babies less than 1200 g birth weight) was negative in terms of reducing the risk of bronchopulmonary dysplasia or death, which was the primary outcome variable, although there were some signs of potential beneficial effects on the severity of the disease at 1 year follow up. This new secondary analysis examines the possible effects of superoxide dismutase on retinopathy of prematurity. Overall there was a small reduction in retinopathy but when the highest risk groups were examined, in particular those under 25 weeks, there seems to be a substantial reduction in retinopathy in the patients who received active treatment. As always you have to be super-careful with secondary analyses and in particular careful with those that were not planned at the time of the initial study design; but this is suggestive and biologically plausible. It probably means we need another larger RCT to examine effects on RoP, but recombinant human SOD is probably very expensive, as most thing are that start with ‘recombinant’, maybe another look at bovine SOD would be worthwhile.

Finally a new version of the AAP guideline on screening for RoP, and the timing of repeat eye exams depending on the initial or subsequent findings. A very clearly written guideline in general. However the section on reducing pain during screening is, how shall I put this, pathetic.   I quote ‘Effort may be made to minimize the discomfort and systemic effect of this examination by pretreatment of the eyes with a topical anesthetic agent such as proparacaine; consideration also may be given to the use of pacifiers, oral sucrose, and so forth.’    So forth!  I notice that the authors of this guideline do not include the committee on fetus and newborn. Which I find a bit strange, and probably the reason the authors say that you ‘may’ make an effort to reduce pain (which they try to minimize I think by calling it discomfort), and you might use ‘so forth’. I think the neonatologists on the committee on fetus and newborn would have had more to say about this, and would have requested the evidence base to be reviewed. Each of the individual methods the authors of this guideline suggest have very limited efficacy. Combined methods, using sucrose, swaddling, soothers and local anesthetics are effective, but not 100%, and should be the routine for retinal examinations.

About keithbarrington

I am a neonatologist and clinical researcher at Sainte Justine University Health Center in Montréal
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