Carlo Bellieni and Celeste Johnston (Conflict of Interest flag, I have collaborated with both of them) have just reviewed a couple of recent years research of analgesic interventions in the newborn. Of 46 randomized studies of painful procedures, 70% had an untreated control group, either placebo or without analgesic intervention.

I have ranted about this before: Pain research in the newborn, what is ethical?, well actually having re-read that post it isn’t really a rant, but a lucid, well-considered and well-argued plea to stop randomizing babies to pain.

The new review shows that the article that I was referring to was not a ‘one-off’ but a persistent pattern. A persistent pattern of unethical research. The discussion section ends like this;

we encourage researchers to perform further studies on new pain treatments by comparing them with with those that have already been validated. we are urging parents and ethics review boards to refuse studies that do not provide acceptable analgesia to all babies enrolled in studies… In addition we are calling on medical journals to refuse to publish studies that deny pain relief to control infants undergoing painful procedures.

I think that editorial guidelines of paediatric journals should be revised to include a clear statement that untreated control groups in studies of painful interventions are not ethical and that articles describing studies with such groups will not be accepted.

I only have one disagreement with the article, and it is the statement that for eye examinations there is ‘no validated treatment that exists’. In fact there are interventions which can significantly reduce pain responses, it is true that they are not perfect, and babies still experience discomfort. But there is a systematic review of local anesthetic drops which shows effect (Dempsey E, McCreery K. Local anaesthetic eye drops for prevention of pain in preterm infants undergoing screening for retinopathy of prematurity. Cochrane database of systematic reviews (Online). 2011;9(9):CD007645).

And multi-modal interventions do have some benefit also (O’Sullivan A, et al. Sweeten, soother and swaddle for retinopathy of prematurity screening: a randomised placebo controlled trial. Archives of Disease in Childhood – Fetal and Neonatal Edition. 2010;95(6):F419-F22.)

The data on sucrose alone are somewhat variable, but as many of the studies are small it is not surprising that some do not show an effect,but many do (such as : Boyle EM, et al. Sucrose and non-nutritive sucking for the relief of pain in screening for retinopathy of prematurity: a randomised controlled trial. Arch Dis Child Fetal Neonatal Ed. 2006;91(3):F166-8).

I think an RCT of pain relief for eye examination that did not incorporate most of these items would also be unethical. A control group should have sucrose, a soother, swaddling, and local anesthetic. The efficacy of this combination is not complete, so a randomized addition of other interventions would be a valuable addition to the literature and to the comfort of our babies.