Congenital Heart Disease Screening in Newborns

Pulse Oximetry Screening for Critical Congenital Heart Defects in Asymptomatic Newborn Babies: A Systematic Review and Meta-analysis

Thangaratinam S, Brown K, Zamora J, Khan KS, Ewer AK
Lancet. 2012;379:2459-2464

Screening for Congenital Heart Disease

Thangaratinam and colleagues aimed to shed light on the potential predictive value of using pulse oximetry to screen for significant cyanotic congenital heart disease (CHD) in newborn infants. One difficulty of determining the potential value of universal screening of newborns with pulse oximetry from previous studies is that the relative infrequency of CHD made any individual study less able to demonstrate benefit.

These investigators used pooled data to perform analyses on a large sample. They identified 13 studies, published from 2001 to 2011, that screened asymptomatic newborn infants for critical CHD defined as disorders from which infants died or required invasive procedures or surgery in the first 28 days of life. These included the following lesions:

• Hypoplastic left heart syndrome;

• Coarctation of the aorta;

• Interrupted aortic arch;

• Transposition of the aorta;

• Aortic valve stenosis;

• Pulmonary valve stenosis;

• Tetralogy of Fallot;

• Pulmonary atresia; and

• Total anomalous pulmonary venous connection.

The 13 studies included a total of 229,000 newborns. From the primary data in those 13 studies, the sensitivity and specificity of pulse oximetry in detecting critical CHD were calculated. Pulse oximetry was performed on the foot only in 8 studies and both hand and foot in 5 studies. With respect to timing, 6 studies completed pulse oximetry screening before 24 hours of life.

In individual studies, the sensitivity of pulse oximetry ranged from 60%-100%, and the specificity in all trials was greater than 98%. The false-positive rates were less than 1% in all except 2 trials, and the highest false-positive rate in any trial was 1.8%. For the pooled data, the sensitivity was 76.5%, with a specificity of 99.9%. The false-positive rate of the pooled data was 0.14%.

Measurement of pulse oximetry before 24 hours of age improved sensitivity from 77.5% to 84.8% (a nonsignificant difference) but increased the false-positive rate from 0.05% to 0.5% (a significant difference). Location of the pulse oximeter probe did not affect sensitivity or the frequency of false-positive results. Thangaratinam and colleagues concluded that pulse oximetry is a highly specific test for detection of critical CHD in newborn infants, and that the false-positive rate is low.

Viewpoint

Given the large number of infants in this analysis, additional data are not likely to change the overall conclusions. The current emphasis on discharging infants at or before 24 hours of age could pose difficulties in instituting pulse oximetry screening programs, but postdischarge screening with pulse oximetry by home visiting nurses could address this issue. It's worth noting that a false-positive rate of 0.14% in the research population of 229,421 infants equates to 321 infants who would require echocardiography because of false-positive results on screening pulse oximetry, so no individual center would have to do many additional echocardiographies for false-positive screens.

The American Academy of Pediatrics endorsed universal newborn screening with pulse oximetry in January 2012^[1] and stated that screening should be performed after 24 hours of age if at all possible and should include readings from both the right hand and either foot. They recommend a "pass" oxygen saturation level of 95%, repeat screens at oxygen saturations of 90%-95%, and immediate evaluation in infants whose pulse oximetry readings are less than 90%.

Abstract

Medscape Pediatrics © 2012  WebMD, LLC

Cite this: William T. Basco. Congenital Heart Disease Screening in Newborns - Medscape - Aug 23, 2012.