The use of pulse oximetry to detect congenital heart disease

Methods: All newborns at a single regional medical center were screened for participation in this study. Patients were excluded from participation if parents refused consent, if a fetal echocardiogram had been performed or if the patient necessitated admission to the neonatal ICU at birth. Prior to hospital discharge a pulse oximetry reading was performed. An oxygen saturation reading ⬎94% was considered normal. Readings between 90 –94% were repeated twice on a different extremity. The screening test was considered positive if the saturation was ⬍90%, less then 94% for three readings or if there was a difference ⬎4% between the upper and lower extremities. If the test was positive, performance of an echocardiogram was recommended to the pediatrician. Results: 90% of births during the study period, 2114 patients, participated in the study. Three echocardiograms were performed secondary to a positive pulse-oximetry screening test; one patient had a complete atrioventricular septal defect, and two children had each had a large ductus arteriosus detected without additional heart disease. One patient with a normal screening test was found at subsequent examination to have total anomalous pulmonary venous return. There was no difference in the number of echocardiograms performed at this single center in newborns between the study period and the control year. Conclusion: Routine use of pulse-oximetry in asymptomatic newborns to screen for congenital heart disease did not add significant expense in this study. The value of pulse-oximetry as a screening test for congenital heart disease in neonates is difficult to judge in this study secondary to the relatively small sample size. Perspective: This is a similar study to that published by Koppel et al. who demonstrated in a larger patient sample a sensitivity of 60% and specificity of 99.9% of pulse-oximetry for detection of critical cardiac disease in the neonate. Limited sample size of the current study limited the authors’ ability to prove similar effectiveness. While screening with pulse oximetry did assist in early detection of one patient with an atrioventricular septal defect, there were also two patients who underwent echocardiography and were each found only to have a large ductus arteriosus. Perhaps routine pulse-oximetry is particularly valuable as a screening tool for ductal-dependent congenital heart disease. However, this study demonstrates that technical expertise is important if pulse oximetry is to be a cost-effective screening test. CG

diography for infective endocarditis and to compare the results within risk subgroups when the von Reyn classification is applied. Methods: The databases of a single large tertiary care children’s hospital were queried for all echocardiograms performed to evaluate for endocarditis between May 1995 and September 2001. Medical record evaluation was performed to categorize cases pre-echocardiogram as either: 1) probable endocarditis including persistently positive blood cultures with either a new murmur or predisposing heart disease and a vascular reaction or a combination of fever, new regurgitant murmur and endocarditis type vascular phenomenon 2) possible endocarditis including positive blood cultures and either predisposing heart disease or vascular changes or a combination of fever, predisposing heart disease and vascular changes or 3) those for whom the diagnosis of endocarditis would be rejected according to the von Reyn classification, patients who did not meet any of the above criteria. All echocardiograms were reviewed for evidence of endocarditis defined as either an oscillating mass involving the valves or other cardiac structures, intracardiac abscess or evidence of a new partial dehiscence of a cardiac valve prosthesis. For each clinical diagnostic category, the incidence of echocardiographic findings of endocarditis was determined. Results: Overall, 101 cases were reviewed. Using pre-echocardiographic criteria, there were 10 patients categorized as having probable endocarditis (group 1), 20 patients with possible endocarditis (group 2) and 71 patients for whom the diagnosis of endocarditis would be rejected according to the von Reyn criteria (group 3). The yield rate for transthoracic echocardiography was 12% overall; 80% for group 1, 20% for group 2 and 0% for group 3. Conclusions: The yield rate of echocardiography as a screening test for endocarditis increases with increased clinical suspicion of endocarditis. Application of the von Reyn criteria to assist in deciding who should undergo screening echocardiography for endocarditis would improve the yield rate and improve resource utility. Perspective: This is a well-designed study and supports the value of careful history and physical examination in determining the likelihood of endocarditis. With a careful preechocardiographic clinical evaluation, excessive ordering of unnecessary transthoracic echocardiograms may be avoided. CG

The Use of Pulse Oximetry to Detect Congenital Heart Disease

The Incidence of Pediatric Cardiomyopathy in Two Regions of the United States

Reich JD, Miller S, Brogdon B, et al. J Pediatr 2003;142:268 – 72.

Lipshultz SE, Sleeper LA, Towbin JA, et al. N Engl J Med 2003; 348:1647–55.

Study Question: The goal of this study was to determine if pulse oximetery can function as a screening test for congenital heart disease in asymptomatic neonates.

Study Question: The goal of this study was to measure the annual incidence of pediatric cardiomyopathy in two re-

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