OBJECTIVE. The purpose of this prospective study was to assess the feasibility and reliability of pulse oximetry screening to detect critical congenital heart defects in a newborn nursery.
METHODS. The study was performed in a large urban hospital with an exclusively inborn population. Stable neonates who had a gestational age of ≥35 weeks and birth weight of ≥2100 g and in whom a critical congenital heart defect was not suspected were admitted to the newborn nursery. When the 4-hour pulse oximetry reading was <96%, pulse oximetry was repeated at discharge, and when the pulse oximetry reading remained at persistently <96%, echocardiography was performed.
RESULTS. Of 15299 admissions to newborn nursery during the 12-month study period, 15233 (99.6%) neonates were screened with 4-hour pulse oximetry. Pulse oximetry readings were ≥96% for 14374 (94.4%) neonates; 77 were subsequently evaluated before discharge for cardiac defects on the basis of clinical examination. Seventy-six were normal, and 1 had tetralogy of Fallot with discontinuous pulmonary arteries. Pulse oximetry readings at 4 hours were <96% in 859 (5.6%); 768 were rescreened at discharge, and 767 neonates had a pulse oximetry reading at ≥96%. One neonate had persistently low pulse oximetry at discharge; echocardiography was normal. Although 3 neonates with a critical congenital heart defect had a 4-hour pulse oximetry reading of <96%, all developed signs and/or symptoms of a cardiac defect and received a diagnosis on the basis of clinical findings, not screening results.
CONCLUSIONS. All neonates with a critical congenital heart defect were detected clinically, and no cases of critical congenital heart defect were detected by pulse oximetry screening. These results indicate that pulse oximetry screening does not improve detection of critical congenital heart defects above and beyond clinical observation and assessment. Our findings do not support a recommendation for routine pulse oximetry screening in seemingly healthy neonates.
I read with interest the article about screening for critical congenital heart disease utilizing pulse oximetry. Screening tests are greatly affected by the pretest likelihood of the disease being screened. In this case it was assumed to be 1.7/1000 in the population studied, which translates into 28 cases. In reality only 4 out of 31 actual cases were included in the study. The others 27 cases were preselected (prenatally or postnatally) and removed form the study. It is hard to validate or invalidate a test based on 4 subjects only.
Because of the pre-selection bias, we do not know whether pulse oximetry would have been able to identify the remaining cases, as the authors did not assess pulse oximetry on those cases. So, if the authors did not assess pulse oximetry, what did they assess? They assessed their setup: prenatal care and immediate post-natal evaluation. The conclusion should reflect this, and may be rephrased to include “in our setup we were able to identify critical heart disease, prenatally and in the immediate post-natal period without the need for a screening test at 4 hour of age” regardless of the nature of that test.
Conflict of Interest:
None declared
Case
Diagnosis
Age in Hours at presentation
Clinical manifestations warranting evaluation
In patient
1
Interrupted Aortic Arch
74
Started at 60 hrs of age.
Normal SpO2 when discharged at 50 hours.
No
2
Fallot'stetrology, Pulmonary atresia with ASD
26
Poor feeding.
SpO2 85-90
Murmur at 26 hours of age
Yes
3
Transposition great arteries with PDA
12
Resp. distress.
Low SpO2.
Grade 2 murmur, at 12 hours of age.
yes
4
Significant LVH with PPHN
2
Low SpO2.
Respiratory distress.
No murmur
Yes
5
DORV with Pulmonary. atresia
14
Low SpO2.
No murmur.
yes
Conflict of Interest:
None declared