Cardiology Flashcards
(35 cards)
How do pediatric cardiac d/o typically present
cyanosis and distress in first few days of life: duct dependent lesions
CHF in first few days of life: Atrioventricular septal defects
Describe flow of oxygenated blood in fetus
- Placenta
- Umbilical vein
- Ductus venosus (bypass fetal liver)
- Inferior vena cava
- Right atrium
- Foramen ovale (preferentially shunted)
- Left atrium
- Left ventricle
- Aorta
- Fetal coronary and cerebral circulation (preferentially directed)
Describe flow of deoxygenated blood in fetus
- Superior vena cava
- Right atrium
- Right ventricle
- Pulmonary artery
- Patent ductus arteriosus (due to high PVR and relatively low SVR)
- Aorta (mixes with oxygenated blood)
- Umbilical arteries
- Placenta
When is anatomic closure of the foramen ovale usually complete?
3 months
When is the ductus arteriosus functionally and anatomically closed (normally)?
- Functionally: 10 – 15 hours
- Anatomically: 2 – 3 weeks
What are the two fundamental and clinically useful formulas for cardiac output and blood pressure?
- Cardiac Output = Stoke volume x HR
2. Blood Pressure = Cardiac output x SVR
List causes of decreased stroke volume in infants and children
- hypovolemia
- myocarditis
- Hypertrophic cardiomyopathy with decreased diastolic filling
- dilated cardiomyopathy with decreased diastolic filling
- pericarditis or pericardial effusion with tamponade
tachydysrhythmias with decreased diastolic filling
When do children achieve the adult ability to increase their stroke volume in order to augment their cardiac output?
8-10yrs
What, after increasing HR, can a child do to compensate for decreased stroke volume and what are clinical correlates?
- Increased SVR manifested as o Increased diastolic BP à narrowed pulse pressure o Paleness o Mottling o Coolness o Delayed capillary refill Weak or thready distal pulses
What maternal illnesses are associated with congenital heart block.
SLE
collagen vascular d/o
List 8 common causes of pediatric chest pain.
- MSK/chest wall pain
- pleurisy
- asthma
- pneumonia
- costochondritis
- gastritis
- GERD
- Precordial catch syndrome (texidor’s twinge)
Describe the hyperoxia test.
- Administer 100% O2 for10 minutes, get an ABG before and after
o Oyxgen saturation
§ Pulmonary: increase > 10%
§ Cardiac: No increases
o PaO2
§ Pulmonary: GT 250 (or increase PaO2 LT 20 – 30%)
§ Cyanotic CHD with reduced pulmonary blood flow or R—L Shunt: LT100
§ Cyanotic CHD with intracardiac mixing: 100-250
What are the three congenital heart lesions with “classic” characteristic findings on CXR
- Tetralogy of Fallot: Boot shaped heart
- Transposition of the Great Vessels: Egg on a string
- TAPVR: Snowman or figure of eight heart
Describe the T wave changes in the pediatric ECG:
- Week 1: upright – if persists can be a sign of RVH
- Juvenile pattern: newborn – age 8; twi V1-V3. May persist into adulthood.
- Teenage: tw upright, adult pattern
What CHD presents with shock
coarctation
aortic stenosis
What CHD presents with CHF
VSD
PDA
What CHD present in the first 2 wks
- TGA
- TAPVR
- tricuspid atresia
- ebstein anomaly of TV
- truncus arteriosus
- pulmonary atresia
- hypoplastic L heart
- hypoplastic R heart
What CHD presents up to 12 wks
tetralogy of fallot
List duct dependent CHD lesions that present with cyanosis
PDA needed for blood flow from Ao to lungs
- tetralogy
- TGA
- tricuspid atresia
- pulmonary atresia
- hypoplastic R heart
List duct dependent CHD lesions that present with shock
PDA needed for blood flow from pulmonary artery to systemic circulation
coarctation
severe Ao stenosis
hypoplastic L heart
List adverse effects of PGE1.
- apnea
- hypotension
- fever
- seizures
- bradycardia
- flushing
- decreased plt aggregation
What is the most common congenital cardiac defect?
VSD
List specific treatments for a tet spell (Box 171-9)
- Place in knees to chest or squat position
- Supplemental O2
- Calm child: fentanyl 1mcg/kg/dose or ketamine 1-2mg/kg IV or 2-4mg/kg IM
- NaHCO3 1mEq/kg IV
- If not working consider:
o Propanolol 0.01mg/kg IV : thought to reduce RVOT spasm
o Phenylephrine 0.01mg/kg IV (same dosing as epi)
List causes of CHF in infants.
- CHD
- Anomlaous left coronary artery
- Myocarditis
- Endocarditis
- Rheumatic heart disease
- Pericardial effusions
- Cardiomyopathies
- Anemia
- Systemic hypertension
- Hypothyroidism
- Electrolyte imbalance
- Cardiac toxins
- Dysrythmias