The effect of handling and immobilization on the response to acute pain innewborn infants

Background. Previous reports have suggested that healthy, full-term newborn infants who are in more aroused behavioral states tend to respond more rob ustly to painful events. Others have shown that acutely ill premature and f ull-term infants who undergo significant handling and immobilization as par t of required nursery procedures respond less robustly to concurrent painfu l events. Purpose. To investigate, using an experimental manipulation, the effect of arousal associated with handling and immobilization on response to acute pa in in generally healthy, premature and full-term newborn infants. Methods. Infants were randomly assigned to a group that underwent a series of handling and immobilization procedures before a heelstick or to a group that underwent the heelstick without previous handling and immobilization. Heart rate, behavioral state, and facial activity were compared between the handled (n = 21) and nonhandled (n = 27) infants during an undisturbed bas eline, a preparatory, and a standard heelstick procedure. Results. In the handled group, heart rate increased over baseline levels in response to the handling but promptly returned to prehandling levels. Ther e were no significant differences between handled and nonhandled groups in mean heart rate, behavioral state, or facial activity during the baseline o r preparatory periods before the heelstick. However, in response to the hee lstick, handled infants had a higher mean heart rate, greater behavioral ar ousal, and displayed more facial activity as compared with nonhandled infan ts. Conclusions. Healthy premature and full-term newborn infants who undergo co mmon nursery experiences such as handling and immobilization as part of the ir routine care can exhibit greater physiologic and behavioral reactivity t o subsequent painful procedures. The effects of the previous handling may b e undetectable, using conventional indices of reactivity, until the painful event. These findings emphasize the importance of identifying reliable mar kers of previous stress, particularly for newborn infants who may become cl inically compromised as a result of the physiologic instability associated with response to pain.