Roofthooft DWE, Simons SHP, Anand KJS, Tibboel D, van Dijk M: Eight years later, are we still hurting newborn infants. Neonatology 2014, 105(3):218-226. The answer is yes, but much less! In this study from a single hospital in Rotterdam with a focus on pain research, there were many fewer painful procedures performed than in the previous study, using a similar methodology, and more sucrose and kangaroo care and other interventions were used for the procedures that were still required. But we can still do better!
One thing the authors noted was that as the number of procedures has decreased, the percentage of unsuccessful procedures has increased. So peripheral arterial lines (which have a high failure rate as the catheters are often around the same size as the artery being cannulated) were unsuccessful 38% of the time in 2001 and 63% of the time in the new cohort. There were a lot fewer of them, so I think this shows that, as we are doing better at being less-invasive, then, when we really need to be invasive, we don’t have the same skills anymore. In our group one or two of us are recognized as having a higher success rate at peripheral lines, so they tend to get asked to do them, and maintain a reasonable success rate, which I think is best for the babies, but when they are not available, what then?
For a much more frequent procedure, peripheral intravenous catheter insertion, success rate dropped from 69% to 62%. So a large number of potentially painful procedures are performed for no benefit. A failed procedure also affects the use of analgesia for the subsequent procedure. If I have put EMLA for a procedure and then fail, re-application may not be possible as time is passing, and I may start to be concerned about toxicity, even sucrose may be less effective if you have to give it multiple times to get a single i.v.
We must find ways of improving success, with new technologies, simulation training etc. I think the next big step forward in neonatal pain control could well be finding ways to reduce unsuccessful procedures.