• Sensory nerve terminals exist on all body surfaces by 22–29 wk of gestation.

• Pain assessment should be performed using validated tools in all patients upon admission and then at regularly defined intervals.
• Physiologic responses to pain include increased circulating levels of catecholamines, increased HR, and increased BP.

• Repeated or long-term painful stimuli result in long-term changes such as a lowered pain threshold.

• Response to painful stimuli contribute to physiologic disturbances such as hypoxia, hypercarbia, acidosis, and hyperglycemia; this may lead to alterations in oxygen delivery and cerebral blood flow.

• Infants have long-term disturbances in pain perception that persist well into childhood.

• An absence of behavioral or physiologic cues that might indicate pain does not indicate an absence of pain.

Behavioral Measures

• Swaddling: Keeping the extremities flexed and close to the trunk

• Pacifiers: Used for non-nutritive sucking

• “Kangaroo care”