CLIPP 18: 2-week male, poor feeding

Question 1

Newborns should regain their birth weight by wheN?

Answer 1

Day 10-14

Question 2

List 4 diagnoses that may cause respiratory distress and difficulty feeding in an infant

Answer 2

CHF
Respiratory infection
Sepsis
Metabolic Disorder

Question 3

Normal respiratory rate in a newborn?

Answer 3

40-60 bpm

Question 4

Can a normal liver edge be palpated in an infant?

Answer 4

Yes: 1-2 cm below the right costal margin

Question 5

Classic findings of CHF in an infant?

Answer 5

Dyspnea with feedings
Diaphoresis
Poor growth
Active precordium
Hepatomegaly

Question 6

Most commonly heard innocent murmur?

Answer 6

The most commonly heard innocent murmur is the Still’s murmur. This is often described as musical or vibratory, and is heard best at the left lower sternal border in the supine position.

Question 7

At what age is an ASD generally first detected?

Answer 7

Age 3-5

The pathognomonic physical finding of an ASD is a widely split, fixed S2, which is a subtle physical finding and difficult to detect on a potentially uncooperative infant with a higher resting heart rate.

Listening for wide splitting of the second heart sound is the most helpful way to distinguish an ASD from an innocent murmur.

Question 8

List 4 heart defects that present with a murmur and signs of CHF in a newborn

Answer 8

VSD
Severe aortic stenosis
Coarctation of the aorta
Large PDA

Question 9

How does tetrology of fallot present?

Answer 9

Cyanosis

Question 10

Three imaging techniques to evaluate a congenital heart defect?

Answer 10

EKG
Echo
Chest X-ray

Question 11

Hallmark Chest x-ray findings on a left to right shunt due to congenital heart defect?

Answer 11

Enlarged cardiac silhouette
Increased vasculature
Pulmonary edema

Question 12

List the three structures of a septum of the heart

Answer 12

the inlet septum (embryologic endocardial cushion)
the outlet septum (embryologic conotruncus) and
the muscular septum (embryologic trabecular septum)

Question 13

What two embryologic errors result in a VSD?

Answer 13

The “fusion” point of these structures is the membranous septum. VSDs occur due to either a lack of tissue (such as an endocardial cushion defect resulting in an inlet VSD) or a lack of fusion (lack of fusion of the embryologic components at the membranous septum, resulting in a “peri” membranous defect)

Question 14

What is the prognosis for a VSD?

Answer 14

VSDs tend to diminish in size with time with spontaneous closure of approximately 75% of small defects and between 25-50% of all defects

Question 15

Why is VSD not heard in the nursery?

Answer 15

The murmur of a VSD will not appear until the PVR drops, usually at a few days to weeks of age. This is why, typically, VSD murmurs are not heard in the nursery

Question 16

List three drugs used in the treatment of congenital CHF

Answer 16

Furosemide
Digoxin- shown to improve symptoms due to VSD in infants
Enalapril- twice daily dosing vs captopril (TID)

Question 17

By what age should surgical decision about VSD closure be made?

Answer 17

6 months

Question 18

What are EKG findings consistent with a VSD?

Answer 18

EKG shows high voltage QRS complexes in leads V1 and V2

Question 19

Describe why you don’t hear the VSD murmur until a few days to weeks of age

Answer 19

A heart murmur from a VSD is typically not appreciated in the immediate newborn period, as the pulmonary vascular resistance is still quite elevated. During this time, since the pulmonary vascular resistance equals the systemic vascular resistance, there is no shunting of blood through the open VSD. However, after a few days to weeks after birth, the pulmonary vascular resistance decreases, and the murmur appears, reflecting the shunted flow of blood through the open VSD (from left to right).

Question 20

What is the normal fetal circulation through the heart?

Answer 20

In fetal circulation, the foramen ovale connects the RA to the LA, allowing a portion of the blood to bypass the RV and the lungs. Approximately a third of the blood that enters the RA passes through this route (preferentially the most oxygenated which is then delivered to the brain and heart), leaving the majority of the blood to travel into the RV. Closure of the foramen ovale is a normal transition from fetal to extrauterine circulation

Question 21

What blood flow causes the murmur in an ASD (marked by a wide-split S2?)

Answer 21

his patient’s murmur is likely caused by an atrial septal defect, which causes flow of additional blood through the pulmonary outflow tract and should be evaluated

Question 22

How might an ASD present?

Answer 22

If the defect is large enough, pediatric patients may present with easy fatigability, recurrent respiratory infections, or exertional dyspnea