Proper location of umbilical venous catheters by internal electrocardioscopy.
D002404:Catheterization; D004562:Electrocardiography; D006325:Heart Atria; D006339:Heart Rate; D006801:Humans; D007186:Incubators, Infant; D007231:Infant, Newborn; D008722:Methods; D014471:Umbilical Veins; D014682:Vena Cava, Inferior