In 1952, Dr. Virginia Apgar, an anesthesiologist at Columbia University developed the Apgar score. The score is a rapid method for assessing a neonate immediately after birth and in response to resuscitation. Apgar scoring remains the accepted method of assessment and is endorsed by both the American College of Obstetricians and Gynecologists and the American Academy of Pediatrics. While originally designed to assess the need for intervention to establish breathing at 1 minute, the guidelines for the Neonatal Resuscitation program state that Apgar scores do not determine the initial need for intervention as resuscitation must be initiated before the 1-minute Apgar score is assigned.
Elements of the Apgar score include color, heart rate, reflexes, muscle tone, and respiration. Apgar scoring is designed to assess for signs of hemodynamic compromise such as cyanosis, hypoperfusion, bradycardia, hypotonia, respiratory depression or apnea. Each element is scored 0 (zero), 1, or 2. The score is recorded at 1 minute and 5 minutes in all infants with expanded recording at 5-minute intervals for infants who score 7 or less at 5 minutes, and in those requiring resuscitation as a method for monitoring response. Scores of 7 to 10 are considered reassuring.
Apgar scores may vary with gestational age, birth weight, maternal medications, drug use or anesthesia, and congenital anomalies. Several components of the score are also subjective and prone to inter-rater variability. Thus, the Apgar score is limited in that it provides somewhat subjective information about an infant’s physiology at a point in time. It is useful in gauging response to resuscitation but should not be used to extrapolate outcomes, particularly at 1 minute as this does hold any long-term clinical significance. Apgar score alone should not be interpreted as evidence of asphyxia and its significance in outcome studies while widely reported is often inappropriate. Resuscitation should always take precedence over calculating a clinical score.
Apgar scoring is recorded in all newborn infants at 1 minute and 5 minutes. In infants scoring less than 7, expanded Apgar score recording is encouraged by the American College of Obstetrics and Gynecology and the American Academy of Pediatrics as a method of monitoring response to resuscitation.
Auscultation with a stethoscope rather than by palpitation of a pulse best assesses heart rate. No other equipment is required. Auscultation has been shown to be a more accurate way to count the pulse as compared to palpation of an umbilical or brachial pulse. A pulse oximeter may also be used.
There are five parts of an Apgar score. Each category is weighted evenly and assigned a value of 0, 1, or 2. The components are then added together to give a total score that is recorded at 1 and 5 minutes after birth. A score of 7 to 10 is considered reassuring, a score of 4 to 6 is moderately abnormal, and a score of 0 to 3 is considered low in full term and late preterm infants. At 5 minutes, when an infant has a score of less than 7, Neonatal Resuscitation Program guidelines recommend continued recording at 5-minute intervals up to 20 minutes. It should be noted that scoring during resuscitation is not equivalent to that of an infant not undergoing resuscitation because resuscitative efforts alter several elements of the score.
The score is calculated as follows:
Grimace Response or Reflex Irritability in Response to Stimulation
Apgar scores were designed to help identify infants that require respiratory support or other resuscitative measures, not as an outcomes measure. The Apgar score alone should not be considered evidence of asphyxia or evidence of an intrapartum hypoxemic event. A low Apgar score of 0 to 1 at 1 minute is not predictive of adverse clinical outcome or long-term health issues since most infants, even those with very low 1-minute scores will have normal scores by 5 minutes. Low Apgar scores at 5 minutes correlate with mortality and may confer an increased risk of cerebral palsy in population studies but not necessarily with an individual neurologic disability. Most infants with low Apgar scores do not go on to develop cerebral palsy but lower scores over time increase the population risk of the poor neurologic outcome. Scores less than five at 5 and 10 minutes correlate with an increased relative risk of cerebral palsy. Neonates with scores less than five at 5 minutes should have umbilical artery blood gas sampling performed. Apgar scores that remain at 0 after 10 minutes may indicate that termination of resuscitative efforts is appropriate as very few infants survive with good neurologic outcomes if no heart rate has been detectable for over 10 minutes.
Apgar scoring may be performed by a physician, midwife, or nurse. Inter-rater variability is quite common as some components of the score are subjective so ideally, the same person should calculate the initial and ongoing scores for consistency. The Apgar score alone should not be considered as evidence of asphyxia or evidence of an intrapartum hypoxemic event. A low Apgar score of 0 to 1 at 1 minute is not predictive of adverse clinical outcome or long-term health issues since most infants, even those with very low 1-minute scores will have normal scores by 5 minutes. Low Apgar scores at 5 minutes correlate with mortality and may confer an increased risk of cerebral palsy in population studies but not necessarily with an individual neurologic disability.