CCHDs (critical congenital heart defects) are serious heart problems present from birth. CCHDs affect how the blood flows in and out of the heart. In the US, 18 out of every 10,000 babies are born with a CCHD, adding up to over 7,000 babies a year.
Many CCHDs are found prenatally by ultrasound. Others are caught quickly after birth when a baby shows signs, including: breathing problems, poor tone, blue color, abnormal heart sounds, poor feeding and lethargy.
And! CCHDs can be tricky: Many babies with CCHDs are vigorous in the first days of life, and their hearts sound normal. They are discharged by the provider as healthy, only to need hospitalization at a later time.
CCHD screening aims to catch these special babies before they begin to struggle. CCHD screen is done at 24-48 hours of age. A pulse oximeter (painless for baby) measures the oxygen saturation on the right hand, and one of the feet. An algorithm is used to compare the two levels.
If a baby passes (a negative result), the likelihood of a CCHD is low, but not zero.
Baby may get a borderline result. This means retesting in an hour or so. A borderline is more likely when baby is crying, nursing, or sleeping. Dehydration, hypoglycemia, and doing the screen before 24 hours may cause a borderline or even false positive.
If a baby fails (a positive result) it doesn’t automatically mean a CCHD, but more evaluation needs to be done.
As you can see, CCHD screens are not perfect. In one study, 880 out of 1755 infants whose CCHDs were diagnosed on or after the third day were estimated to have passed their screens. One study found the CCHD screen falsely predicted CCHDs in 14 out of 10,000 babies.
43 states now require CCHD screening by facilities before baby’s discharge. More and more home birth providers are offering the CCHD at the 1-2 day home visit.