Skin conductance as pain indicator in newborns: a comparison study with heart rate, oxygen saturation and pain behavioral scales

Introduction Heart rate (HR), oxygen saturation (OS) and skin conductance activity (SCA) are physiological markers of acute pain. Neonatal Facial Coding System (NFCS), Neonatal Infant Pain Scale (NIPS) and modified COMFORT are validated pain behavioral scales. Objective It was to compare whether the scores of these measures fit the psychophysical parameters for a pain marker (intensity, reactivity, direction, regulation and slope). Method Observational prospective study including 41 newborns, in which it were compared the maximum HR, the minimum OS, the SCA variables number of waves per second (NWps) and relative area under the curve of waves (AUC), and the scores of behavioral pain scales in the periods before, during and after heel prick. Results The parameters intensity and regulation were significant for the NWps (p<0.01), AUC (p<0.05), HR (p<0.01), OS (p<0.01), NFCS (p<0.01), NIPS (p<0.01) and modified COMFORT (p<0.01). The reactivity and direction parameters were significant for all variables (all p<0.01), except to AUC (p>0.05). The slope was significant for the minimum OS and NIPS and modified COMFORT scales (p