Cardiovascular Emergency

Normal pediatric HR:

• Neonate: 150-180
• Infant: 145-150

 

Normal pediatric BP:

(In pediatrics, we worry more about hypotension than hypertension)

• Neonate -> anything below 60 is hypotensive
• Infant -> anything below 70 is hypotensive
• 1-9 yo -> Minimum SBP = 70 + (2 x age)
• > 9 yo -> like “adults”

 

Presentation of cardiac problems:

• ↓ feeding
• ↓ feeding
• ↓ activity
• SOB

 

Normal closure of PDA:

• Functional: 48 hrs
• Anatomical: 4-6 wks

 

Types of cardiac diseases in pediatrics:

• Congenital
• Acquired
• Electrophysiology

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a. Congenital Heart Diseases

1) Cyanotic CHD:

• (present usually on the 2^nd – 3^rd week)

Tetralogy of fallot: (right -> left shunt)

1. RVH
2. Pulmonary\infundibular stenosis
3. VSD
4. Overriding aorta

• RV outflow obstruction
• Paroxysmal hyper-cyanotic attacks (tet spells)
• Auscultation: harsh systolic ejection murmur + thrill {upper sternal border}, single S2
• CXR: heart = boot, dark lungs bc ↓ pulmonary blood flow
• Tx: PGE, definitive surgery after 4 mo

 

Tricuspid atresia: (right -> left shunt)

• No blood flow from RA to RV -> flows through ASD, PDA, VSD
• Auscultation: no significant murmur, single S2
• Tx: PGE, surgery
  • SE of PGE? Hypotension and apnea

 

Ebstein anomaly:

• Downward placement of tricuspid valve
• Auscultation: holocystolic murmur, gallop rhythm
• ECG: WPW

 

Transposition of the great arteries: (mixing)

• Aorta arises from RV, pulmonary A arises from LV -> 2 parallel circuits -> need ASD, VSD, PDA
• Seen in IODM
• Auscultation: single S2
• CXR: heart = egg on string
• Tx: PGE, definitive arterial switch in the first 2 wks of life

 

Truncus arteriosus: (mixing)

• Single arterial trunk + VSD (always)
• Seen in DiGeorge syndrome
• Auscultation: systolic murmur, loud single S2

 

Total anomalous pulmonary venous return: 

• Usually pulmonary venous returns into the left atrium, if it goes to the right -> mix -> cyanosis
• CXR: heart = snowman

 

 

2) Stenotic CHD:

Pulmonary stenosis: 

• Obstruction to RV outflow -> RVH
• Auscultation: ejection systolic murmur + thrill {left 2^nd-3^rd ICS}
• Tx: balloon valvulopolasty, surgery

 

Aortic stenosis: 

• Mostly caused by bicuspid valve -> obstruction to LV outflow
• Auscultation: ejection systolic murmur + thrill {right 2^nd-3^rd ICS}
• Tx: balloon valvulopolasty, surgery

 

Coarctation of the aorta:

• Infantile: preductal
  • Differential cyanosis
  • Tx: PGE, surgery

• Adult: juxtaductal\just below
  • Seen in Turner syndrome
  • Presentation: lag of femoral pulses, BP of UL > LL
  • CXR: rib-notching
  • Tx: treat HTN, surgery

 

3) Non-cyanotic CHD:

VSD: (left -> right shunt)

• Most common congenital heart lesion
• Large defect -> ↑ pulmonary flow -> ↑ PVR -> medial hypertrophy -> Eisnmenger (when PVR > SVR)
• Subtypes: small\large, muscular\membranous (more common)
• Auscultation: pansystolic\holosystolic murmur + thrill {lower left sternal border}
• CXR: large heart
• Tx: most small muscular (less membranous) close in the first 1-2 yrs
• When to operate? FTT, failure of medical correction of HF, infants w\ large defects
• Complication: HF, pulmonary HTN, endocarditis

 

ASD: (left -> right shunt)

• Most commonly ostium secundum defect (region of fossa ovalis)
• Auscultation: systolic ejection murmur + fixed slit of S2
• Tx: usually close on their own, but if persists after 5 yrs -> close it surgically before puberty (why? If becomes pregnant -> increases the workload on the heart)

 

AVSD: (left -> right shunt)

• Defect in the endocardial cushion -> defective AV valves
• Seen in Down syndrome

 

PDA: (left -> right shunt)

• A duct still being present 1 mo after birth
• More in girls, preterm, maternal rubella infection
• Presentation: wide pulse pressure, bounding peripheral pulses
• Auscultation: continuous machinery murmur
• Tx: indomethacin (PG inhibitor) (better results w\ preterm), surgical ligation (better results w\ term)

 

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b. Aquired Heart Disease:

Myocarditis:

• Organism: Coxsackie B virus
• Presentation: fever, HF, arrhythmias
• Dx: biopsy
• Tx: HF and arrhythmias

 

Pericarditis:

• Same presentation as myocarditis except + distant and muffled HS
• Organism: GAS (S. agalactiae), staph
• Tx: underlying cause, pericardiocentesis if effusion
• ECG:

 

Infective endocarditis:

• Organism: strept viridians, staph aureus
• High risk pts? On central line, high outflow CHD (VSD, aortic stenosis), cardiac surgery, dental procedure, artificial valve
• Presentation: prolonged fever, splenomegaly, new murmur, splinter hemorrhage, Osler nodes, Janeway lesions, Roth spots
• Dx: Duke’s criteria (2 major OR 1 major + 3 minor OR 5 minor)
• Tx: organism specific for 4-6 wks, HF meds, surgery (interactable failure, abscess, recurrent emboli, increased size of vegetations, worsening regurg)
• Prophylaxis: amoxicillin to high risk pts
• Complications: HF from valve lesions (aortic\mitral), emboli (bc of vegetation)

 

Acute rheumatic fever:

• Organism: GAS
• Associated w\ strept pharyngitis
• Dx: Jone’s criteria
• Tx:
  • For GAS eradication: oral penicillin for 10 days (erythromycin if allergic)
  • For the arthritis\carditis: anti-inflammatory (aspirin if no HF, prednisone if w\ HF)
  • Phenobarbital (only if chorea)
• Prophylaxis: continuous abx (single IM benzathine penicillin G every mo)

 

Kawasaki:

• Medium vessels vasculitis (mainly coronary)
• Complications: aneurysm
• Tx: aspirin (to prevent MI) and immunoglobulin

 

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c. Arrhythmias:

Sinus tachycardia:

• Caused by something external, either fever, crying, hypovolemia

 

SVT:

• If more than 1 yr > 180
• If less than 1 yr > 220
• ECG: no P wave (very close QRS), constant R-R (means the HR is constant regardless of the environment, bc the origin is in the heart, where in sinus tachycardia, the origin is from outside, so the R-R will change according to the causative agent either fever, crying, hypovolemia)
• Tx:
  • Stable -> adenosine (first dose = 0.1 mg\kg, max is 6 mg\kg) -> not improving -> adenosine (second dose – 0.2 mg\kg, max is 12 mg\kg) -> not improving -> amiodarone -> not improving -> cardioversion
  • If unstable (↓BP, perfusion, consciousness) -> cardioversion then adenosine

 

V tach: (wide complex)

• Pulse -> amiodarone -> cardioversion
• No pulse -> CPR -> epinephrine -> DC shock

 

V fib:

• CPR -> epinephrine -> DC shock

 

Asystole:

• CPR only!

 

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Innocent murmur:

• Systolic
• Grade 2\6 or less
• Intensifies w\ increased cardiac output (exercise\fever)
• Change in intensity w\ posture or head position
• No thrill, no heave, no abnormal HS, no radiation, no Sx
• Types: peripheral pulmonic stenosis, still’s murmur, venous hum, aortic outflow murmur

 

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Download the PDF version: here

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References:

• Dr Alhammad’s clinical notes
• Kaplan step 2 lecture notes