The Apgar scale is a metric for determining the vital signs of a newborn at 1 and 5 minutes post-delivery, according to the University of Maryland Medical Center. It was developed as a way of monitoring the health of babies undergoing anesthesia, says Wikipedia, and was adopted by obstetricians and midwives as a way of quickly assessing whether or not a newborn requires immediate medical care.
The Apgar scale was developed by anesthesiologist Virginia Apgar in 1952, explains the UMMC. According to Wikipedia, the scale's name, APGAR, eventually became a mnemonic acronym to help practitioners remember its key metrics. These refer to the child's appearance (skin color), pulse (presence and quality of the heart rate) grimace (reflex irritability), activity (strength and muscle tone) and respiration (presence, rate and quality).
Each element of the scale is scored on a scale of 0 through 2, notes Wikipedia, and the scores for each category are added together to set the overall score. The test is usually administered twice, once after the first minute and again after 5 minutes, and scores of 7 and up indicate normal function. Scores between 4 and 6 suggest the need for medical intervention, and a score of less than 3 is considered a sign of a critical problem.