Skin conductance as a marker of pain in infants of different gestational age.

AIMS: To assess the use of skin conductance as an objective measure of pain in infants of different gestational age. A second aim was to investigate the relationship between skin conductivity and selected physiological and behavioural variables (oxygen saturation, heart rate and behavioural state).

METHODS

Infants were divided according to gestational age into the following 3 groups; group A: 25+0-31+6 weeks (13 infants), group B: 32+0-35+6 weeks (25 infants), group C: 36+0-41+6 weeks (19 infants). The pain stimulus was blood sampling.

RESULTS

The most sensitive parameter for describing changes in skin conductance related to pain was peak per second. No other parameter correlated with the physiological variables chosen. The results showed that the inability to determine basal skin conductance is a crucial disadvantage to practical application. The lack of correlation between conductance parameters and gestational age is surprising.

CONCLUSION

We conclude that the Peak per Second is the best parameter for evaluating skin conductance in infants and it is not influenced by gestational age. Peaks per Second correlate only with Prechtl's Scale of behavioural state and not with the physiological parameters chosen.