A blinded comparison of clinical and echocardiographic evaluation of the preterm infant for patent ductus arteriosus.
The accuracy of the characteristic physical signs of a patent ductus arteriosus (PDA), that is, a systolic murmur, increased volume of pulses and increased praecordial activity, in diagnosing a haemodynamically significant PDA in ventilated premature infants was prospectively evaluated. Fifty-five ventilated preterm infants (birthweight < 1500 g) had daily echocardiographic and clinical evaluation for a PDA for the first 7 days of life. The examiners were blinded to each other's findings. Probability analysis was performed for the accuracy of each clinical sign in detecting a haemodynamically significant PDA as defined by echocardiographic criteria. Clinical signs were poor at detecting a significant PDA in the first 4 days of life. On day 1, none of the 10 infants with a significant PDA had a murmur. By day 4, clinical signs were better at detecting a significant PDA, but specificity remained poor with many false positive signs. Six infants had murmurs with a closed duct. The development of echocardiographic haemodynamic significance preceded the development of physical signs by a mean of 1.8 days. Significant ductal shunts often occurred silently, but the development of a murmur often marked an increase in the velocity of the flow through the duct rather than an increase in the size of a shunt. This study confirms that echocardiography is required for the reliable early diagnosis of a PDA in ventilated preterm infants.
Department of Perinatal Medicine, King George V Hospital for Mothers and Babies, Royal Prince Alfred Hospital, Camperdown, New South Wales, Australia.
R
R
Skelton
N
N
Evans
J
J
Smythe
D004374:Ductus Arteriosus, Patent / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004452:Echocardiography; D006439:Hemodynamics; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D012680:Sensitivity and Specificity; D016037:Single-Blind Method