Anesthesia for the micropremie.

Providing anesthesia for the micropremie involves many considerations beyond what is needed for the full-term neonate. Immaturity of the airway, lungs, cardiovascular system, liver, kidneys, and central nervous system makes the micropremie susceptible to anesthestic complications. Immature respiratory mechanisms and respiratory control increase the risk of apnea, hypoxemia, and hypercapnia intraoperatively as well as postoperatively. Anesthetic drugs depress myocardial contractility and impair baroreflexes in the micropremie to increase the risk of hypotension during anesthesia. Drug metabolism in the micropremie is slow because of the immature liver and kidneys. The micropremie brain requires less drug to achieve the anesthetized state. As a result, administration of the dose and timing of anesthetic drugs differs in the micropremie compared with the full-term neonate. This article describes anesthetic considerations for a few surgical prodedures common in the micropremie.