Newborns are examined immediately after birth to quickly assess their respiratory effort, circulation, and temperature; to identify any major congenital abnormalities; and to check for any infectious or metabolic disease that requires immediate treatment. This exam is critical to ensure the transition to extrauterine life proceeds without difficulty. The infant should then undergo a complete physical examination within 24 hours of birth and again at discharge. Specific findings in an infant who has experienced a traumatic birth are reviewed in detail in Chapter 83.
It is best to perform a routine newborn physical exam under a radiant warmer with the lights on. Before even touching the infant, observe and assess color, activity, posture, maturity, and respirations. Perform the examinations that cause the least amount of disturbance first. It is easier to listen to the heart and lungs first and feel the pulses when the infant is quiet. Warming the hands and stethoscope before use decreases the likelihood of making the infant cry.
In addition to examination of the infant, the complete maternal history, including prenatal, perinatal, labor and delivery, family, and social history, should be reviewed. (See Appendix D, “Chartwork.”)
Temperature. Indicate whether the temperature is rectal (which is usually 1° higher than oral), oral, or axillary (which is usually 1° lower than oral). Axillary temperature is usually measured in the neonate, with rectal temperature done if the axillary temperature is abnormal. Normal axillary temperature in a newborn ranges from 97.5°F to 99.3°F (36.5–37.4°C).
Respirations. The normal respiratory rate in a newborn is 30 to 60 breaths/min. Periodic breathing (≥3 apneic episodes lasting >3 seconds within a 20-second period of otherwise normal respirations) is considered normal and common in newborns.
Blood pressure. Blood pressure correlates directly with gestational age, postnatal age of the infant, and birthweight. (For normal blood pressure curves, see Appendix C.)
Heart rate. The normal heart rate is 70 to 190 beats/min in the newborn (usually 120–160 beats/min when awake, >170 beats/min with activity or crying, and decreasing to 70–90 beats/min when asleep). In the healthy infant, the heart rate increases with stimulation. See Table 53–1.
Pulse oximetry. Pulse oximetry in the neonatal intensive care unit (NICU) has become standard of care and is sometimes referred to as the “fifth vital sign.” (Note: Pain assessment has also been referred to as the “fifth vital sign” by some.) It is a simple, painless noninvasive tool used to measure arterial oxygen saturation by measuring the absorption of light in tissue beds. It is commonly used in the NICU as a monitoring tool during oxygen supplementation, during sedation for procedures, perioperatively, in high-risk infants, in the delivery room, and during transport. Pulse oximetry is also used diagnostically in persistent pulmonary hypertension and to screen for critical congenital heart disease (CCHD). Screening pulse oximetry for critical cyanotic heart disease is ...