A neonate is a baby in the first 4 weeks of life, and preterm neonates are those born at less than 37 weeks gestation. Based on weight, neonates have twice the metabolic rate, twice the minute ventilation and twice the cardiac output of adults. A neonate’s larynx in high in the neck to allow feeding while breathing. Because it is so high, flexing the neck during intubation (the sniffing position) does not improve the view of the larynx. Intubation is usually straightforward however, and videolaryngoscopes are now often used routinely. The control of respiration is poorly developed in preterm neonates, and they are prone to apnea after anesthesia. Neonates are also prone to hypoglycemia and usually receive 10% glucose with 0.2% saline while fasting. Additional isotonic fluid is given to replace losses of salt-rich body fluids. Fetal hemoglobin is the predominant type of hemoglobin at birth, falling to less than 1% of the total by 1 year of age. The high proportion of fetal hemoglobin is one reason a higher transfusion threshold is used in neonates. Most metabolic enzyme systems are immature at birth, affecting the doses of morphine, paracetamol and muscle relaxants among others, and increasing side effects from others, including propofol. Anesthesia is required for many different surgical procedures in neonates. Dealing with significantly smaller anatomy and more extreme proportions requires skill and appropriately sized equipment. Less robust physiology demands more care and attention to detail before during and after anesthesia. This cohort can also present with some unique pathology requiring equally specific surgery.
KeywordsEndotracheal intubation, neonate Tracheo-esophageal fistula, anesthesia Neonatal apnea and anesthesia Neonatal pharmacology Neonatal laparotomy anesthesia
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