Postoperative Schmerztherapie bei Säuglingen

Summary

Three lines of evidence support the idea that infants are capable of pain perception similar to that in adults.

It has been shown that the neural substrate necessary for pain perception is already present in a newborn infant. The human nervous system has the capacity to transmit nociceptive information to the brain and the brain has the capacity to process this information by the time of birth and perhaps for some time before birth.

Various physiological responses to painful stimuli, such as variations in heart rate and blood pressure, sweating and cutaneous flexor responses, and changes in the so-called stress hormones, were found and investigated in newborn and even preterm infants. Some of these data suggest that the threshold for pain perception may be lower in newborn than in older babies.

Infants show characteristic facial expressions as a response to pain, indicating that reaction to pain involves higher centres of the nervous system.

Thus there is reasonable evidence that infants receive pain and have adverse physiological consequences from pain. Pain treatment in newborn infants is therefore important for both humanitarian and medical reasons.

Recognition and measurement of pain and evaluation of pain therapy are difficult tasks, and mostly we are left with estimating pain intensity from physiological variables or observation of patient’s behaviour.

There are several differences in pharmacokinetics and pharmacology of opioids in neonates compared to babies older than 3 months. It is our clinical impression that this leads to respiratory complications more frequently in newborn babies than in older infants and adults.

When opioids are used in newborn infants, the starting dose should be about half the dose given to older children (on a mg/kg body weight basis), and infants so treated should be monitored for apnea and if possible hypoxaemia.