Erfahrungen zur Analgosedierung in der pädiatrisch-neonatologischen Intensivmedizin

Summary

As even small premature babies have functional nociceptive systems and can show unwanted, or even dangerous, stress responses, the best possible treatment of pain and best sedation should be guaranteed in paediatric and neonatal intensive care medicine. It has been shown in one study that providing the particular physiological features of children are adequately taken into account, narcotic analgesics can be highly appropriate for this purpose. Children who are adequately treated with analgesics and sedatives make better progress, the hormonal stress reaction is at least attenuated and may not occur at all, and metabolic disasters do not occur to the same extent as is observed when no treatment for relief of pain is given. With respect to the particular features of the physiology in childhood, it must be born in mind that:

• 1. Resorption can be faster, especially after intramuscular injection.

• 2. In view of the smaller pool capacity and the higher unbound fraction in the plasma than in the adult, a larger effective fraction must be assumed on distribution of the drugs given.

• 3. Metabolism in the liver and excretion by the kidneys will proceed with some delay during the first 3–6 months of life.

Care must be taken to see that the circulation is stable and hypovolaemia is not present, as neonates in particular can respond to the administration of sedatives and/or analgesics with a drop in blood pressure.

Morphine and fentanyl are particularly suitable for use for analgo-sedation in artificially ventilated preterm and full-term neonates; owing to its shorter duration of action and good controllability fentanyl has advantages over morphine.

When additional sedation is necessary, pentobarbitone can be given in this group of patients as a short-term infusion, in a single dose of 2–3 mg/kg body weight. When adequate analgo-sedation is achieved with this combination, artificial ventilation of preterm and full-term neonates is well tolerated. The infants’ own respiratory impulsion, which can be prejudicial to mechanical respiration, is largely suppressed, and the consumption of other analgesics, sedatives and catecholamines is decisively lower. When infants undergo sedation with barbiturates alone, without analgesic medication, as is quite common, the heart rate and blood pressure are not different from after administration of fentanyl; in the first 3 days of treatment the mean blood pressure is even somewhat with fentanyl. Analgo-sedation with fentanyl also has drawbacks, however: elevation of the bilirubin value and delayed elimination of meconium.

A combination of fentanyl and midazolam is suitable for analgo-sedation in infants being mechanically ventilated. Care must be taken to ensure that when both are infused simultaneously the dose of midazolam is smaller.

In addition to the broad spectrum of pharmacological treatments, it is important that particular attention be given to the provision of a quiet environment and that to minimize fear and stress, contact between the children and their parents be encouraged, which is perfectly well possible even during mechanical ventilation.