Abstract
As a medical student and no less than during my training as a pediatrician and neonatologist in the 1960s and 1970s, the subject of neonatal pain was simply not part of the curriculum. The initial Board Certification exam for Neonatology in 1974, of which I was a candidate, did not include questions as to the management, let alone prevention of neonatal pain. Simply put, the conventional wisdom was that newborns, especially premature infants, were less sensitive, if not actually insensitive to noxious stimuli and that if there was a response at all to any stimulus, it was “reflexic” and therefore not “sensed” by the infant and surely did not have any long-term adverse effects.
As such, there were no standardized recommended measures of how to minimize the pain from the seemingly minimal discomfort of a heel stick, let alone from the more traumatic procedures of intubation or the insertion of a chest tube for treatment of an acute pneumothorax.
It was not until the 1980s1,2 that we began to acknowledge that infants are, if anything, more sensitive to pain stimuli, that neonatal pain has immediate negative physiologic consequences let alone long-term sequala. 3 In contrast today, there are recommended standardized protocols of the use of both pharmacologic and nonpharmacologic approaches to prevent or at least minimize the pain of procedures in the care of the newborn.
Most convincing has been the documenttion 4 that a variety of nonpharmacologic measures can be utilized to minimize pain in the newborn including the ingestion of 20% glucose/sucrose, breastfeeding during the procedure, feeding of breast milk, swaddling of the newborn, oral stimulus with a pacifier and even the sounding of white noise.
This month's issue of Breastfeeding Medicine includes a major review by Shi and colleagues of the efficacy of the use of a various nonpharmacologic measures with an emphasis of the role of the ingestion of breast milk. The two major conclusion of the detailed meta-analysis was that the act of breastfeeding consistently reduces pain, while the feeding of breast milk per se has a variable and not consistent benefit. The conclusion of the authors was that the act of breastfeeding has additional positive features (e.g., tactile, vestibular, thermal stimuli) beyond the ingestion of the breast milk. The second conclusion was that the ingestion of 20% glucose was the most consistent and efficacious measure to minimize the pain of the procedural noxious stimuli, let alone it being more logistically possible and available as compared to the act of breastfeeding.
Part of the challenge of evaluating the efficacy of the various tested substances is how to best measure/quantitate pain in the newborn. Pain by definition is what the patient perceives/senses and thus varies by threshold differences, degrees of pain tolerance, and the competing distractions of other sensory stimuli. Thus only “the patient him/herself tells us if it hurts and how much, a response obviously precluded by the immature nonverbal developmental stage of the newborn.”
As such, various scoring scales (NPASS, CHIPPS, NIPS) 5 have been developed based on the observer's perception of the facial responses and motor activity of the newborn plus some physiologic measures (heart respiratory rate). All of these scores have a degree of observer subjectivity and thus are prone to a measure of bias concluding that what is needed is more absolute “objective” tool. Thus, a most intriguing article has been recently published by Carlini et al. 6 of a preliminary study of utilizing the tools of artificial intelligence (AI) to develop a more objective measure of scoring of pain with an automatic pain assessment tool—clearly another measure of the future as we merge AI with our standard clinical observations.
A last word from my vantage as the Editor in Chief. To date Breastfeeding Medicine continues to receive studies ostensibly assessing the efficacy of a new nonpharmacologic substance or procedure in reducing neonatal procedural caused pain. These studies are based on a methodology of comparing the responses of the study group to those of a matched control group who did not receive any substance. Such manuscripts are rejected out of hand, as it is our opinion that subjecting the control group infants to a painful procedure without providing any analgesic measure violates basic ethical principles. It is clear that what would be acceptable is to compare the “new “to what is the standard (such as 1 cc of 20–24% glucose/sucrose).
Of even more concern is the fact that such studies were approved by institutional human investigation committees (Helsinki committees). This is most perplexing and disconcerting as it suggests that these committees were not cognizant as to what are the standards of neonatal care. In comparison, they would not have approved a study evaluating the efficacy of a new antibiotic for the treatment of an infectious process as compared to the outcome of a control group who had not received the established standardized treatment with its known degree of success. Surely, infants deserve to be treated and investigated by the same ethical and scientific standards and principles as other humans.