Behavioral response to pain in drowsy and sleeping neonates: a randomized control study.

In a randomized controlled design, 100 healthy, term neonates in the first week of life, undergoing heel prick for routine screening were randomized to receive a heel prick in either the drowsy/sleeping state or the awake (but not fussy or crying) state. 48 babies in sleeping or drowsy states and 47 in the awake states were analyzed. Infants in the drowsy/sleeping states scored significantly lower on the Neonatal Infant Pain Score (NIPS) (median score 5) at 30 seconds post stimulus compared with infants in higher states of alertness (median score 6). They also had a shorter total duration of cry (29.17 sec ± 8.95 vs 32.67 sec ± 9.82). However, there was no difference in the NIPS score between the two groups at 45 seconds post stimulus. We concluded that babies in the drowsy/sleeping states of alertness at the time of a painful stimulus appear to show a less intense behavioral response to pain as compared to those in the awake state.