The effects of different procedures on pain levels in preterm and term infants in neonatal intensive care unit: a cross-sectional survey of pain assessment in newborns

Background Newborns show a series of behavioral and physiological reactions to painful stimuli. Aims The current study aimed to determine the effect of different procedures on the pain levels of newborns in the Neonatal Intensive Care Unit (NICU). Methods One hundred ninety-six newborns with gestational age (GA) of 23-40 weeks, birth weight (BW) between 2235 +/- 911 g were included. Painful procedure (PP) (vascular access (VA), heel prick (HP), umbilical catheter (UC), orogastric catheter (OC), and intubation (I)) were recorded. Pain during the PP was evaluated with Neonatal Infant Pain Scale (NIPS). Pulse and O-2 saturation were recorded before (BP), during (DP) and after (AP) procedure. Results NIPS total scores were found to be significantly higher with term infants (p < 0.05). When NIPS total scores were compared according to the type of PP, significant difference was observed between groups (p = 0.000). Positive correlation was found between birth week (p = 0.000, r = 0.364), BW of infants and NIPS total score (p = 0.000, r = 0.371), pulse values of DP and NIPS total score (p = 0.000, r = 0.386). Negative correlation was found between O-2 saturation values DP and the NIPS total scores (p = 0.000, r = -0.405). Conclusions It is concluded that as GA and BW increase, so do the pain responses of the infant, which showed that the pain thresholds of term-preterm infants are different, and decrease as GA and BW increase.