We’ve all heard the phrase, “pain is what the patient says it is”… Patient self-report is the gold standard of pain assessment is basic nursing 101, but what about the non-verbal neonate?
Ongoing assessment, monitoring, and treatment of pain remains one of the most challenging aspects of neonatal care. Although assessment tools such as the Premature Infant Pain Profile (PIPP) or N-PASS: Neonatal Pain, Agitation and Sedation Scale have shown high interrater reliability in the literature, they still lack a certain objectivity.
What if we could measure pain and the effectiveness of our pain interventions through brain imaging and monitoring?
That’s exactly the focus of a recently published paper by Oxford University researchers reviewing various approaches to measure noxious-evoked brain activity and the possibility of using these measures to:
- Measure pain-related brain activity in the neonate
- Assess the efficacy of analgesics
- Assess the efficacy of nonpharmacologic approaches to pain management
Pain Assessment through Brain Imaging and Monitoring
The Oxford Team discusses various tools that may be used to measure noxious-evoked brain activity in the neonate, which are summarized below.
Near-infrared Spectroscopy (NIRS)
NIRS uses infrared technology to measure local tissue oxygenation. When placed on tissue overlying the brain, it can be used to detect changes in cerebral oxygenation. Studies have shown that a NIRS sensor placed on the scalp can detect increased cerebral oxygenation associated with noxious stimuli. These increases occur even when the patient is sedated, and typically assessed pain responses may be dampened or absent.
EEG uses scalp electrodes to detect and record electrical brain activity. Researchers have been able to record certain patterns of activity associated with noxious stimuli, and use these templates to study the efficacy of analgesia. For example, application of a local anesthetic was shown to modulate the noxious-evoked brain activity demonstrating its efficacy in procedural pain management.
Functional Magnetic Resonance Imaging (fMRI)
fMRI using a technique called blood oxygenation level dependent (BOLD) imaging has been used to map pain responses in the brains of adults, and develop a so-called neurologic signature for pain detection. This technique would be particularly useful in measuring the effectiveness of analgesics to optimize Central Nervous System (CNS) drug development.
EMG measures and quantifies muscle activity and has applications in the study of pain in which reflex responses to noxious stimuli can be mapped. Studies using both EMG and noxious-evoked brain activity have shown that reflex responses occur in preterm neonates to both noxious and non-noxious stimuli reinforcing the need for accurate pain assessment in this vulnerable population.
Points for Practice
- Noxious-evoked brain activity may occur without visible pain-related behaviors
- Interventions such as sucrose may decrease pain-related behaviors but have no effect on noxious-evoked brain activity
- Many factors influence individual neonatal response to noxious input such as sex, prior pain, stress and illness.
While more research is needed in the area of brain imaging and monitoring in pain assessment, multimodal approaches that include measures of noxious-evoked brain activity hold promise for a more complete picture of the neonatal pain experience.
We’d love to hear from you!
What are your views on brain imaging and monitoring for neonatal pain assessment? Are you using any of these approaches in your NICU?
Want to learn more about neonatal pain? Access the 2019 ONE Conference Recording and view “Neonatal Pain and Brain Development” by Diane Wilson, NNP.
Source: Gursul, D., Hartley, C., & Slater, R. (2019). Nociception and the neonatal brain. Seminars in Fetal and Neonatal Medicine, doi:10.1016/j.siny.2019.05.008
Blog written by Sarah Bakke
Sarah Bakke, BSN, RNC-NIC
Sarah started her career in a level III NICU in Indiana, and has worked in both level III and IV NICUs over the course of her career. She is currently a staff nurse in the NICU at the Nemours Alfred I. duPont Hospital for Children in Wilmington, DE, and is working towards her MSN as a Pediatric Nurse Practitioner at Drexel University.
She has led a number of neuroprotective initiatives during her time at Nemours including launching a language nutrition program, founding a multidisciplinary NeuroNICU committee, and organizing quality improvement projects. Sarah is passionate about all things NeuroNICU.