Can cry in the newborn be used as an assessment of pain?

Neonatal pain perception, management and review of practises among medical workers in Nigeria newborn units

Background

Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. The perception of pain is variable and knowledge may not match practise.

Aims

To ascertain the knowledge, attitude and practice of neonatal pain management (NPM) among HCW in newborn units across Nigeria.

Methods

The validated questionnaire administered to consenting doctors and nurses working in various newborn units in Nigeria was utilised.

Results

There were 256 respondents from tertiary institutions 228 (89.1%) located in 31 states of Nigeria. There were 91% doctors and 8.6% nurses'. The perception of newborn pain was high (≥95%) among doctors and nurses . Up to 67.1% of the doctors and 57.1% of nurses were aware of NPM. One third (37.3%) of doctor respondents knew of NPM from friends and colleagues while half of the nurses knew from course textbooks.Pain definition was in most by sensation (94%), 50% by emotion. Most nurses were aware of the subjective report of potential tissue damage and knew the facial expressions of pain compared to doctors. Crying was equally recognised as an expression of pain. Perception of non-pharmacologic methods of NPM was highest for massaging and KMC; the knowledge of Sucrose analgesia was low. Procedural pain perception was poor and analgesia was for few procedures.

Conclusions

Perception of pain was high but did not match knowledge and practice of NPM. Formal education on NPM was lacking in the training of HCW.

Neonatal pain analyzer: development and validation

We developed a pain analyzer (ABC analyzer) to perform automatic acoustic analysis of neonatal crying and to provide an objective estimate of neonatal pain. The ABC analyzer uses a validated pain scale (ABC scale) based on three acoustic parameters: pitch frequency, normalized RMS amplitude, and presence of a characteristic frequency- and amplitude-modulated crying feature, defined as "siren cry". Here we assessed the reliability of the analyzer. We enrolled 57 healthy neonates. Each baby was recorded with a video camera during heel prick. Pain intensity was evaluated using a validated scale [Douleur Aigue du Nouveau-Né (DAN) scale] and the analyzer and the two scores were compared. We found a statistically significant concordance between the DAN score and ABC analyzer score (p < 0.0001). The ABC analyser is a novel approach to cry analysis that should now have its properties carefully evaluated in a series of studies, just as is necessary in the development of any other pain measurement tool.