Agpar scoring offers an useful initial assessment of a neonate’s physiological status and fetal to infant transition, but more data should be collected to adequately assess infants in distress that require additional interventions during the scoring period.
Apgar scoring is a standard assessment for newborn babies, but may not be the most thorough or accurate assessment of mortality or long-term neurological effects, according to a revised statement from the American Academy of Pediatrics (AAP) Committee on Fetus and Newborn and the American College of Obstetricians and Gynecologists (ACOG) Committee on Obstetric Practice that recommends the use of an expanded Apgar protocol.
“The Apgar score provides an accepted and convenient method for reporting the status of the newborn infant immediately after birth and the response to resuscitation if needed,” the statement notes. “[However] the Apgar score alone cannot be considered as evidence of, or a consequence of, asphyxia; does not predict individual neonatal mortality or neurologic outcome; and should not be used for that purpose. An Apgar score assigned during resuscitation is not equivalent to a score assigned to a spontaneously breathing infant. The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists encourage use of an expanded Apgar score reporting form that accounts for concurrent resuscitative interventions.”
Apgar scoring was developed in the 1950s as a rapid assessment of the clinical status of a newborn at 1 minute of age to determine the need for prompt intervention to establish breathing. The standardized assessment that resulted from the initial rapid screening includes scoring on a scale of 0 to 2 based on the infant’s color, heart rate, reflexes, muscle tone, and respirations. The scoring is performed at 1 and 5 minutes after birth, and at subsequent 5-minute intervals for 20 minutes thereafter for infants with a score of less than 7.
While Apgar scoring is useful as an initial assessment tool, particularly in healthy infants, AAP and ACOG say it has been used inappropriately to predict individual adverse neurologic outcomes. The agencies say the revised Apgar statement updates a 2006 version with new guidance from a 2014 report titled “Neonatal Encephalopathy and Neurologic Outcome” from ACOG and AAP, along with new guidance on neonatal resuscitation.
“The guidelines of the Neonatal Resuscitation Program state that the Apgar score is useful for conveying information about the newborn infant’s overall status and response to resuscitation,” according to the statement. “However, resuscitation must be initiated before the 1-minute score is assigned. Therefore, the Apgar score is not used to determine the need for initial resuscitation, what resuscitation steps are necessary, or when to use them.”
However, the statement notes that Apgar scores of 0 beyond 10 minutes of age may be useful in determining whether continued resuscitation efforts should be indicated, since AAP and ACOG say few infants with those scores survive such lengthy resuscitation with normal neurologic outcomes.
The 2014 Neonatal Encephalopathy and Neurologic Outcome report definesâ¨a 5-minute Apgar score of 7 to 10 as “reassuring;” a score of 4 to 6 as “moderately abnormal;” and a score of 0 to 3 as “low” or possibly indicative of non-specific illness or possible encephalopathy in term and late preterm infants.
The revised statement also clarifies that, despite findings of distress in infants with low Apgar scores, the scoring is not a specific indicator for poor outcomes and has lead to “an erroneous definition of asphyxia.”
“The Apgar score by itself does not equal 'asphyxia,’” Kristi Watterberg, MD, professor of pediatrics and neonatology at the University of New Mexico School of Medicine and one of the report authors says.
“Asphyxia is defined as the marked impairment of gas exchange, which, if prolonged, leads to progressive hypoxemia, hypercapnia, and significant metabolic acidosis. The term asphyxia, which describesâ¨a process of varying severity and duration rather than an end point, should not be applied to birth events unless specific evidence of markedly impaired intrapartum or immediate postnatal gas exchange can be documented on the basis of laboratory test results,” the report notes.
The revised statement also notes that, despite its benefits, the Apgar has drawback in that it is a subjective assessment of an infant’s physiologic condition at 1 specific point in time. Many factors can affect the score, including maternal sedation, interobserver variability, trauma, and more-but biochemical disturbances must be profound to affect the score. Apgar scoring may also be affected by variations in normal fetal to infant transition. The AAP and ACOG give the example of infants with initial low oxygen saturations that do not require supplemental oxygen-the Neonatal Resuscitation Program targets for oxygen saturation are 60% to 65% at 1 minute and 80% to 85% by 5 minutes.
“The healthy preterm infant with no evidence of asphyxia may receive a low score only because of immaturity,” according to the statement. “The incidence of low Apgar scores is inversely related to birth weight, and a low score cannot predict morbidity or mortality for any individual infant … it is also inappropriate to use an Apgar score alone to diagnose asphyxia.”
The statement also notes that Apgar scores assigned during resuscitation are not equal to those assigned to an infant breathing on their own.
“The concept of an assisted score that accounts for resuscitative interventions has been suggested, but the predictive reliability has not been studied. To correctly describe such infants and provide accurate documentation and data collection, an expanded Apgar score reporting form is encouraged,” says AAP and ACOG. “This expanded Apgar score may also prove useful in the setting of delayed cord clamping, in which the time of birth (ie, complete delivery of the infant), the time of cord clamping, and the time of initiation of resuscitation can all be recorded in the comments box.”
The expanded Apgar reporting form includes boxes that can be checked for any resuscitative efforts made during the scoring period, including supplemental oxygen, positive pressure ventilation, chest compressions, and the administration of epinephrine. The expanded form also includes a comments section to list other factors, such as maternal medications and response to resuscitative efforts.
“We recommend use of an expanded Apgar scoring sheet to better communicate the resuscitation that was happening when the Apgar score was awarded,” says Watterberg. “I think this recommendation is important for all those who attend deliveries.”
Overall, the statement recommends that the Apgar not be used to predict individual infant mortality or neurologic outcomes, and that Apgar scores alone not be used for asphyxia diagnoses without further evidence of impaired gas exchange during the intrapartum or immediate postnatal periods. For infants with an Apgar scores of 5 or less at 5 minutes, umbilical arterial blood gas samples should be obtained, as well as pathological examination of the placenta.
While AAP and ACOG affirm that the Apgar score is not accurate as a predictive tool for individual mortality or adverse neurological outcome, scores of less than 5 at 5 and 10 minutes may indicate an increased risk of cerebral palsy. However, the agencies note that not all low scores are equal, and are affected by many factors.
“You can't predict an individual outcome from the individual 5-minute Apgar score, but in population studies, a low 5-minute Apgar score is statistically associated with increased mortality, cerebral palsy and poor neurologic outcomes,” Watterberg says. “Even then, the majority of babies with low Apgar scores will not have cerebral palsy. This information is important for counseling parents who have had an infant with low Apgar score (0-3 at 5 minutes).”