Congenital Heart Disease Flashcards
Congenital Heart Disease
Most common congenital anomaly
A major cause of death in 1st year of life
Can be structural and/or conductive
Etiology:
- 90% unknown
- multifactorial inheritance
- risk factors - maternal, family history
- associated with chromosomal abnormalities, syndromes or congenital defects in other body systems
- Gene mapping research
Increased Pulmonary Blood Flow (3)
Atrial septal defects
Ventricular septal defects
Patent Ductus arteriosus
Obstruction to systemic blood flow (3)
Coarctation of the Aorta
Aortic stenosis
Hypoplastic Left Heart Syndrome
Decreased Pulmonary Blood Flow (2)
Tetralogy of Fallot
Pulmonic Stenosis
Mixed blood flow
Transposition of the Great Arteries
Truncus Arteriosus
Hemodynamic Classification: Increased pulmonary blood flow
- Left-to-right shunt
- Cause HF
Hemodynamic Classification: Decreased pulmonary blood flow
Right-to-left shunt if septal defect present
Cause cyanosis
Hemodynamic Classification: Obstruction to systemic blood flow
Increased pressure load on left ventricle -> decreased CO (shock)
Signs of poor CO; HF (cyanosis on right side)
Hemodynamic Classification: Mixed blood flow
Saturated & desaturated blood mix within heart or great arteries -> variable clinical picture
Cyanosis & HF
Defects with Increased Pulmonary Blood Flow
Left-to-right shunt: connection of left & right sides of heart (septal defect), or of great arteries (PDA)
S&S of HF: increased blood volume on right side increases pulmonary blood flow at expense of systemic blood flow
Defects that obstruct systemic blood flow
Blood exiting heart mets area of anatomic narrowing (stenosis) causing obstruction to blood flow
- increase pressure in ventricle & great artery before obstruction
- Decreased pressure in area beyond obstruction
Defects with Decreased Pulmonary Blood Flow
Obstruction of pulmonary blood flow & anatomic defect (ASD or VSD)
Right to left shunt
Hypoxemic & usually cyanotic
Hypercyanotic Spells (Tet spells): Clinical Manifestations
- increased rate & depth of respiration
- increased cyanosis
- Increased heart rate
- Pallor & poor tissue perfusion
- Agitation or irritability -> may lead to limpness or seizures
Hypercyanotic Spells: Treatment
- Knee-chest position (decreases venous return, shunting blood to vital organs, reduces cardiac workload)
- calm, comforting approach
- administer 100% oxygen
- give SC or IV morphine
- begin IV fluid replacement & volume expansion, prn
- Repeat morphine administration
Mixed Defects
Survival in post-natal period depends on mixing of blood from pulmonary & systemic circulations within the heart chambers
Pulmonary congestion
Decreased CO
Clinically - some degree of desaturation (cyanosis may not be visible) & HF
CHD: Conduction Disorders
Issue with conduction in the heart that cause arrhythmias in children
- Bradycardia: heart block.
- tachycardia: wolff-parkinson-white, supraventricular tachycardia, Long QT
Symptoms:
- syncope
- lightheadedness
- dizzness
- SOB
- Palpitations or skipped heartbeats
- Exercise intolerance
- Difficulty feeding
- Cyanosis
- Cardiac arrest
Conduction Disorders Treatment
Vagal maneuvers
medications
cardioversion
catheter ablation
pacemaker or implantable cardioverter defibrillator
2 main clinical manifestations of CHD
Hypoxemia
Heart Failure
Hypoxemia
PaO2 < normal (80-100 mmHg)
Desaturated venous blood enters systemic circulation without passing through lungs
3 Types of Defects cause cyanosis
Right to left shunt (teralogy of fallot), mixing or arterial & venous blood within chambers of heart, transposition of great arteries
Consequences of chronic Hypoxemia
Polycythemia - risk for thromboembolism
Clubbing - chromic tissue hypoxia & polycythemia
Hematologic abnormalities (thrombocytopenia, abnormal platelet function, fewer coagulation factors, prolonged clotting time -> increased risk of post-op bleeding)
Dehydration
Bacterial endocarditis
CNS injury (stroke, meningitis, brain acscess)
Hypoxemia during feeding
fatigue with feeding, poor weight gain, tachypnea, dypsnea on exertion, poor exercise tolerance
negative developmental outcomes
Squatting; hypercyanotic spells - blue spells or “tet” spells
Hypoxemia: Nursing Interventions (KOMMPP)
- oxygen administration “with caution”
- prevent hypercyanotic spells (dehydration, crying) and provide calming and comforting measures
- monitor CBC
- monitor for bleeding (bruising, petechiae, epistaxis)
- knee to chest position
- parent education
Heart Failure Definition
Inability of heart to pump adequate amount of blood to systemic circulation at normal filling pressures to meet body’s metabolic demands
causes of HF
- volume overload (L-R shunts. Ventricle to hypertrophy)
- pressure overload (obstructive lesions: stenosis)
- decreased contractility (cardiomyopathy, myocardial asphyxia)
- high cardiac output demands (Sepsis)
HF Management: Goals of treatment (4)
Improve cardiac function (increase contractility and decrease afterload)
Remove accumulated fluid & sodium (decrease preload)
Decrease cardiac demands
Improve tissue oxygenation & decrease oxygen consumption
Improve Cardiac Function: Digitalis (aka. Digoxin)
Increases force of contraction
Decreases heart rate & slows conduction of impulses through AV node
Indirectly enhances diuresis by improving renal perfusion
Nursing Considerations Digitalis
Observe for signs of toxicity
Check apical pulse before administering (if < 90-110 you will hold)
Proper calculations & measuring are essential (rare to give > 1.0 mL)
Discharge teaching
Signs of digitalis toxicity
bradycardia
dysrhythmias
anorexia
n&v
Improve Cardiac Function: Angiotensin-Converting Enzyme (ACE) inhibitors
Reduces afterload
Nursing considerations:
- monitor BP before & after administration (hypotension)
- monitor serum electrolytes - block action of aldosterone & are postassium sparing
- carefully assess renal function
Remove accumulated fluid & sodium
administer diuretics (give early in day) - lasix and spirolactone
accurate I&O
daily weights -> same time, same scale
observe for signs of dehydration or edema
observe for signs of electrolyte imbalance (if potassium is imbalanced they are at increased risk of digoxin toxicity)
fluid restriction rarely needed
- if required, plan to give most fluids during waking hours
possible sodium restriction
Decrease Cardiac Demands (6)
Limiting activity
Cluster nursing care (allow periods of uninterrupted rest, minimal handling)
Minimize unnecessary stress (sedation prn)
Monitor temperature - hyperthermia, hypothermia: prevent and treat infections promptly
Maintain neutral thermal environment
Prevent skin breakdown from edema
Improve tissue oxygenation & decrease oxygen consumption
Monitor for & treat respiratory distress
- count RR for full minute
- position with HOB elevated or sitting up
- provide for unrestricted chest expansion
Remember: babies are diaphragmatic breathers!
- oxygen administration: only if appropriate given their goal saturation parameters
HF - Nursing Considerations
Maintain nutritional status
- greater caloric needs but impaired ability to take in adequate calories
- well rested before feeds; feed soon after awakening (minimize energy expenditure on crying)
- q3h feeding schedule - individualize to infant’s needs
- Allow no more than 1/2 hour to complete feed -> NG prn
- increase caloric density of formulas (add corn oil, or formula to breastmilk)
Post-op Cardiac Surgery: Nursing Considerations
Monitor risk of altered cardiac output
Monitor for respiratory distress
Blake chest tubes
Monitor for arrythmias
External pacemaker
Monitor for infection
Dressing and wound care
Manage pain
Provide adequate nutrition
Support patient and family
Coping
Discharge planning and teaching
