1. Maternal Drug Use during Pregnancy. Maternal drug use (cocaine, marijuana) during pregnancy may result in premature birth; intrauterine growth retardation; and cardiovascular abnormalities, including low cardiac output.
2. Temperature Control and Thermogenesis
   1. Newborns are at risk for significant metabolic derangements caused by hypothermia. (Newborns do not shiver, increase activity, or effectively vasoconstrict like older children and adults do in response to cold.)
   2. Placing the patient on a forced-air warming blanket may dramatically reduce conductive heat loss.
   3. Anesthetic agents may reduce or eliminate thermogenesis, removing any ability to compensate for cold stress.
3. Respiratory Distress Syndrome
   1. Exogenous surfactant has been widely used in premature infants of low birth weight to either prevent or treat RDS.
   2. One of the long-term consequences of RDS is bronchopulmonary dysplasia. Many patients improve as they age, but reactive airways, recurrent pulmonary infections, and prolonged oxygen requirements are seen in some patients.
      1. Anesthetic concerns in these patients include baseline oxygenation and the potential presence of active bronchoconstriction.
      2. These patients often benefit from an additional bronchodilator before induction. Although postanesthetic tracheal intubation is not usually required, a high index of suspicion should be used if there is significant clinical evidence of poor lung function before surgery.
4. Postoperative Apnea
   1. Apnea and bradycardia are well-recognized, major complications that are possible during and after surgery in neonates. The infants at highest risk are those born prematurely, those with multiple congenital anomalies, those with a history of apnea and bradycardia, and those with chronic lung disease. Hypothermia and anemia can also contribute to the development of postoperative apnea.
   2. Infants with life-threatening apnea and bradycardia before surgery may be taking central nervous system stimulants (caffeine, theophylline [metabolized to caffeine]). Administering caffeine (10 mg/kg) prophylactically to infants at risk of postoperative apnea to ensure adequate serum levels may prevent the need for prolonged periods of postoperative ventilatory support.
   3. Spinal anesthesia without sedation decreases the incidence of postoperative apnea and bradycardia in high-risk infants, but this advantage is lost if supplemental sedation is used.
5. Retinopathy of Prematurity (ROP)
   1. Very preterm infants, especially those weighing <1,200 g, are at highest risk for ROP, with an incidence of significant disease of about 2%.
   2. The most common cited cause of ROP is hyperoxia from administered oxygen, but hypoxemia, hypotension, sepsis, intraventricular hemorrhage, and other stresses have also been implicated.
   3. The primary anesthetic challenge in these patients is related to their extreme prematurity and small size. Adequate monitoring, vascular access, and thermal stability are common challenges to management. Use of supplemental oxygen at pulse oximetry saturations of 96% to 99% does not cause additional progression of prethreshold ROP.
6. Neurodevelopmental Effects of Anesthetic Agents
   1. Studies have shown that prolonged exposure (equivalent to several weeks of continuous exposure in humans) of animal models to anesthetic agents can lead to neurodegenerative changes in the developing brains of neonatal rats.
   2. Currently, no conclusive evidence demonstrates the deleterious effect of inhaled or IV anesthetics on neurocognitive function in neonates and infants (development of learning disabilities when exposed to multiple anesthetics before 2 years of age).

Neonatal Anesthesia

1. Physiology of the Infant and the Transition Period
2. Anatomy of the Neonatal Airway
3. Anesthetic Drugs in Neonates
4. Anesthetic Management of the Neonate
5. Special Considerations
6. Surgical Procedures in Neonates