A newborn infant has mild cyanosis, diaphoresis, poor peripheral pulses, hepatomegaly, and cardiomegaly. Respiratory rate is 60 breaths per min, and heart rate is 250 bpm. The child most likely has congestive heart failure caused by which of the following?
a. A large atrial septal defect and valvular pulmonic stenosis
b. A ventricular septal defect and transposition of the great vessels
c. Total anomalous pulmonary venous return
d. Hypoplastic left heart syndrome
e. Paroxysmal atrial tachycardia
the answer is below…
The United States Medical Licensing Examination, or USMLE for short, is a three-part licensing examination that is required in order to receive a license to practice medicine within the United States.
The USMLE assesses a physician’s ability to apply knowledge, concepts, and principles, and to determine fundamental patient-centered skills that are important in health and disease and that constitute the basis of safe and effective patient care.Examination committees composed of medical educators and clinicians from across the United States and its territories prepare the examination materials each year.
This exam is designed by the Federation of State Medical Boards and the National Board of Medical Examiners to determine whether or not an individual understands and can apply the knowledge necessary to practice medicine safely and intelligently.
The USMLE is actually comprised of three different exams that are referred to as steps, which examine the individual’s knowledge of specific topics related to the field of medicine such as basic science, medical knowledge, medical skills, clinical science, and the application of all of these skills and areas of knowledge in the medical field.
All three steps of the USMLE include a series of computerized multiple-choice questions, but the format of the exam and the information covered in each multiple-choice section is different for each step of the USMLE. The USMLE Step II also has a clinical skills portion that examines an individual’s ability to work with real patients and the USMLE Step III has a computerized patient simulation portion in addition to the multiple-choice section of the exam. In order for an individual to receive a license to practice medicine, the individual must pass all three steps of the USMLE.
The correct answer is e; Paroxysmal atrial tachycardia.
Congestive heart failure from any cause can result in mild cyanosis, even in the absence of a right-to-left shunt, and in poor peripheral pulses when cardiac output is low. Congestive heart failure from many causes can be associated with a rapid pulse rate (up to 200 beats per min). A pulse rate greater than 250 beats per min, however, should suggest the presence of a tachyarrhythmia. Common causes for supraventricular tachycardia includes Wolff-Parkinson-White (WPW) syndrome, congenital heart disease, and sympathomimetic drugs. In this patient, evaluation for WPW and cardiac abnormalities must be accomplished after the congestive heart failure from the increased heart rate is under control.