Cardiac Flashcards
What is the most common cause of a cyanotic baby?
Tetrology of Fallot
Areas to auscultate
Upper R sternal border (base/aortic)
U L sternal border (pulmonic)
LRSB (tricuspid)
LLSB (apex)
Cardiac physical exam
What color is the baby?
Respiratory distress?
Diaphoretic?
Palpate
Palpation during cardiac exam
Extremity pulses Femoral pulses BP(Doppler) The chest Precordium Thrills?
Heart defects with increased pulmonary flow
Patent ductus arteriosus (PDA) Septal defects (ASD, VSD) Atrioventricular canal (AVC) defect **L to R shunting ** fix these defects **L high pressure ** pulmonary congestion, pulmonary drowning ** these patients demonstrate s/s of HF
Heart defects that are obstructive
Coarctation Pulmonary stenosis (PS) Aortic stenosis (AS) **s/s of coarctation: increased pressure in upper extremities with bounding pulses, headaches, dizziness ** obstructive = blood cannot get out
Heart defects with decreased pulmonary flow
Tetralogy of Fallot
Transposition
** Tetralogy of Fallot = VSD, PS, Overriding aorta, RV hypertorphy
Urine Output
1mL/kg/hr
Diaphoresis
sign of low cardiac output
S/S of CHF
cardiac enlargement tachycardia tachypnea diaphoresis weak pulses decreased UOP Gallop rhythm
Treatment for CHF
Digoxin
Lasix
Fluid restriction
Inotropes
Treatment of cyanosis
Low O2 or RA Maintain sats 75 PGE (prostaglandin E) Cardiac cath. Surgery
Normal ductus arteriosis closure
1st breath causes a sharp increase in PAO2 and causes the ductus arteriosis to close.
CXR
- most frequently ordered radiologic test for children with suspected cardiac problems.
- provides a permanent record of the heart’s size and configuration, its chambers, and the great vessels as well as the pattern of blood flow, especially in pulmonary vessels.
Decreased HgB
- s/s of tissue hypoxia because of diminished O2 binding capacity. Tx: packed RBCs
- Chronic hypoxia: polycythemic; thick blood. Risk for stroke. Keep very well hydrated.
Cardiac cycle
systole and diastole
Cardiac output
volume of blood ejected by the heart over one minute
Stroke volume
volume of blood ejected by the heart per contraction
Preload
Volume of blood returning to the heart, or circulating blood volume.
**Circulating blood volume is easiest to assess clinically using the central venous pressure. (CVP)
Afterload
Volume of blood against which the heart has to beat. Also known as BP or systemic vascular resistance.
**a higher BP indicates greater afterload.
Frank-starling law
As preload increases, stroke volume increases and as stroke volume increases, cardiac output increases.
-It is also how we describe contractility.
CHF in kids is most commonly caused by
congenital heart defects (CHD)
CHF in kids described
- kids have both right and left sided HF
- RV is shot. This leads to increased RV end diastolic pressure which causes everything to back up. This creates increased central venous pressure, systemic engorgement (JVD, hepatomeglea, generalized edema)
- L side; pulmonary congestion
Goals of tx in CHF
- improve cardiac function
- remove accumulated fluid and sodium
- decrease cardiac demands
- improve tissue oxygenation
- decrease O2 consumption
Assessment of early S/S of CHF
***Tachypnea** tachycardia, esp. during rest and slight exertion profuse scalp sweating fatigue and irritability sudden weight gain respiratory distress
Digoxin (pre-administration assessment)
Apical pulse must be assessed for 1 full minute.
Withhold if pulse is lower than 90-110 bpm (70 older kids_
CHF and ACE inhibitors
They are prescribed to decrease afterload and the workload of the heart.
PT education regarding digoxin
- 1 hour before or 2 hours after feedings
- use calendar to track dose administration
- do not mix medicine with food or fluids
- if a dose is missed and more than 4 hours has elapsed, withhold the dose and give the next dose at the scheduled time; if less than 4 hours has elapsed, administer the missed dose.
- if the child vomits, do not redoes
- if more than 2 consecutive doses have been missed, notify the physician. Do not increase or double to dose for missed doses.
S/S of digoxin toxicity
- decreased HR
- S/S of flu
- S/S of overdose
- vomiting
Mixed Cardiac Defects
Transposition of the great arteries or vessels (TGA, TGV)
Hypoplastic left heart syndrome (HLHS)
What to do during a hypercyanotic spell
- place infant in knee-chest position
- administer 100% oxygen via facemask
- administer morphine as prescribed
- administer IV fluids as prescribed
- *PGE given with transposition to keep the ductus arteriosis open.
Kawasaki’s Disease (KD)
- known as mucocutaneous lymph node syndrome and is an acute systemic inflammatory illness
- cause is unknown, may be associated with an infection rom an organism or toxin
- cardiac involvement is the most serious complication
- aneurysms can develop
- swelling system wide
Acute Stage of KD
- High, unresponsive fever
- Conjunctiva hyperemia (Very red eyes, no drainage)
- red throat
- Swollen hands/feet
- Red palms and soles
- Enlarged cervical lymph nodes
Subacute stage of KD
- Fever subsides
- cracking lips and fissures
- Peeling skin on fingers and toes
- Arthritic-like joint pain
- Cardiac manifestations (i.e. coronary aneurysms)
- Thrombocytosis and hypercoagulability
- *These kids are usually monitored in the ICU.**
Cardiovascular disorders in children are divided into 2 major groups:
Congenital heart defects
Acquired heart disorders
Congenital heart defects fall into 2 broad categories:
Heart failure (HF) Hypoxemia
SA Node
- pacemaker of the heart
- initiates an impulse
Cardiac output calculation
HR X SV
Contractility
refers to the efficiency of myocardial fiber shortening, or the ability of the cardiac muscle to act as an efficient pump.
Peripheral tissue assessment
Pulses
Warmth of extremities
Capillary refill
Decreased contractility is suspected if:
the extremities are cool with thread pulses and diminished urinary output.
Medications that improve contractility include:
digoxin (Lanoxin)
dopamine (Intropin)
dobutamine (Dobutrex)
What is the most common response to changes in cardiac output?
Adjustments in heart rate
Characteristics of HR
it is slowest during sleep and can more than double with strenuous physical exercise.
Causes of heart conditions in infants may include:
- mother with chronic health condition (lupus)
- medications such as phenytoin (Dilantin)
- maternal alcohol/drug use
- infections such as rubella in early pregnancy
- LBS r/t IUGR
- high birth weight r/t DM
There is an increased risk of congenital cardiac defects if:
Either parent or a sibling has a heart defect. Marfan syndrome and hypertrophic cardiomyopathy are hereditary.
An acceleration of heart rate with inspiration in children is:
Normal
Differences in BP between upper and lower extremities may indicate:
Coarctation of the aorta.
What percentage of children have an innocent murmur of one type at some point during childhood?
80%
The most important nursing responsibility following a pediatric heart cath. is observing the following signs of complications:
- Pulses, esp. below the cath. site
- Temp/color of affected extremity
- VS q 15 min with emphasis on HR (1 full min)
- BP, hypotension is bad
- Dressing for bleeding or hematoma formation
- Fluid intake, both IV and oral
- infants for hypoglycemia
Pediatric heart cath. nursing altert
If bleeding occurs, direct continuous pressure is applied 2.5cm (1 inch) above the percutaneous skin site to localize pressure over the vessel puncture.
What is the major cause of death (other than prematurity) in the first year of life?
Congenital heart disease (CHD)
The most common heart anomaly is
Ventricular septal defect
Care after cardiac cath.
- remove pressure dressing 1 day after cath.
- cover site with bandaid for several days, putting new one on every day for next 2 days.
- keep site clean/dry
- no bath x 3 days
- older children may shower 1st day after cath.
- observe site for s/s of infection
- no strenuous exercise for several days, school is ok
- resume regular diet w/o restrictions as tolerated
- Tylenol/motrin for pain
- F/U with dr as scheduled
Trisomy 21 (Down syndrome) and trisomy 13 and 18 are highly correlated with
congenital heart defects
Pressure on the left and right side of the heart
Normally the pressure on the right side of the heart is lower than the pressure on the left side of the heart.
Left-to-right shunt
Caused by an abnormal connection between the heart chambers, such as a septal defect, where blood flows from an area of higher pressure (left side) to one of lower pressure (right side).
Normal chamber pressures and O2 saturations
IVC: 8 and 78% RA: 3 / 72 and 80% RV: 25/0-5 and 72-80% PA: 25/15 and 72-8% PV: 9 and 95: LA: 5-10 and 95% LV: 120/0-5 and 95% Aorta: 115/80 and 95%
Defects that cause left-to-right shunting of blood cause symptoms of:
HF
Pulmonary hypertension is:
- an uncommon condition
- may occur as a result of congenital heart defects
HF is:
the inability of the heart to pump an adequate amount of blood to the systemic circulation at normal filling pressures to meet the body’s metabolic demands.
Causes of HF are:
- Volume overload (left-to-right shunting)
- Pressure overload (obstructive lesions)
- Decreased contractility
- High cardiac output demands (sepsis, hyperthyroidism, severe anemia)
HF occurs most frequently….
secondary to CHDs in which structural abnormalities result in an increased volume load or increased pressure load on the ventricles.
Septal defects can cause:
large left-to-right shunts, which result in a volume load on the RV.
Obstruction to flow of the LV, such as narrowing of the aorta (coarctation of the aorta) can cause:
increased pressure inside the ventricle.
Diseases in other organ systems, particularly the lungs can cause:
HF
Obstructive changes in the lungs result in:
increased pulmonary vascular resistance, which increases the RV workload.
Cor pulmonale is the term for:
HF resulting from obstructive lung disease such as cystic fibrosis or bronchopulmonary dysplasia.
As the capacity of the compensatory mechanisms is exceeded, the child exhibits signs of HF because of:
decreased myocardial contraction
increased preload
increased afterload
The s/s of HF can be divided into three groups:
- impaired myocardial function
- pulmonary congestion
- systemic venous congestion
* *because these hemodynamic changes occur from different causes and at differing times, the clinical presentation may vary among children.
One of the earliest signs of HF is:
tachycardia (sleeping HR>160 in infants) as a result of sympathetic stimulation. HR is elevated even during rest but becomes extremely rapid with the slightest exertion.
Ventricular dilation and excess preload result in:
extra heart sounds, S3 & S4, referred to as a gallop rhythm
Decreased cardiac output results in:
poor perfusion, manifested by cold extremities, weak pulses, slow capillary refill, low BP, and mottled skin.
Extreme pallor or duskiness is an ominous sign.
Pulmonary congestion:
Tachypnea (RR>60 b/m in infants) occurs in response to decreased lung compliance.
Tachypnea can lead to hypoxemia because O2 does not reach the alveoli for gas exchange in adequate amounts with fast breathing rates.
Mild cyanosis is relieved by O2 administration.
Costal retractions.
Dyspnea.
Poor feeding and decreased weight gain.
A late sign of heart failure is
Gasping & grunting with respirations
Infants with HF have:
an increased metabolic rate and require additional caloric intake to grow.
The most common s/s of dig toxicity in infants and children are:
bradycardia
anorexia
nausea/vomiting
Therapeutic serum digoxin levels range from
0.8-2 mcg/L
Dosing for digoxin
- infants rarely receive more than 1 mL (50 mcg or 0.05mg) in one dose.
- a higher does is an immediate warning of a dosage error.
- To ensure safety, compare the calculation with that of another staff member before giving digoxin.
Foods high in potassium
Bananas Oranges Whole grains legumes leafy vegetables
Cyanosis is seen with
Tetralogy of Fallot
Single ventricle
Transposition
Hypercyanotic spells/ blue spells/ tet spells (all the same)
- rarely seen before 2 months of age
- occur most frequently in the 1st year of life and more often in the morning.
- may be preceded by feeding, crying, or defecation
Nursing care for tet spells:
- place in knee-chest position
- employ calm, comforting approach
- administer 100% O2 via facemask
- administer morphine as prescribed
- administer IV fluids if needed/prescribed
Blalock-Taussing shunt
directly anastomosed the subclavian artery to the pulmonary artery to provide pulmonary blood flow and was the 1st operation devised for patients with cyanotic heart disease.
Atrial septal defect
abnormal opening between the atria. Blood will flow from the left atrium to the right. There will be right atrial and ventral enlargement. patients may be asymptomatic.
Ventricular septal defect
abnormal opening between the right and left ventricles. Many VSD’s close spontaneously. Most likely to close on its own in the 1st year of life. L-R shunting. HF is common. There is a characteristic murmur.
Atrioventricular canal defect
incomplete fusion of the endocardial cushions. Consist of a low ASD that is continuous with a high VSD and clefts at the mitral and tricuspid valves which creates a large central atrioventriciular valve that allows blood to flow between all four chambers of the heart. It is the most common heart defect in children with Down syndrome. Patients usually have moderate to severe HF. There is a murmur. May be cyanotic with increased crying.
Patent ductus arteriosis (PDA)
failure of the fetal ductus arteriosis to close within the first weeks of life. The continued patency of this vessel allows blood to flow from higher-pressure aorta to the lower-pressure pulmonary artery, which causes a l-r shunt.
The effect of the altered circulation is an increased workload on the left side of the heart, increased pulmonary vascular congestion and possibly resistance and potentially increased right ventricular pressure and hypertrophy.
PT may be asymptomatic or show signs of HF. There is a machinery-like murmur. Indomethacin (PG inhibitor) has proven successful in closing a PDA in premature infants and some newborns.
Coarctation of the aorta
Localized narrowing near the insertion of the ductus arteriosus, which results in increased pressure proximal to the defect and decreased pressure distal to the obstruction. Patient may present with high blood pressure and bounding pulses in the arms, weak or absent femoral pulses, and cool lower extremities with lower blood pressure. There are signs of HF in infants.
Aortic stenosis
Narrowing or stricture of the aortic valve, causing resistance to blood flow in the left ventricle, decreased cardiac output, left ventricle hypertrophy, and pulmonary vascular congestion. The prominent anatomic consequence of AS is hypertrophy of the left ventricular wall.
Tetralogy of Fallot
Four defects:
VSD + PS + overriding aorta + RV hypertrophy
-cyanosis is common
-There is a characteristic murmur.
Transposition
TGS, TGA
the vessels are exactly opposite of where they are supposed to be.
Hypoplastic Left Heart Syndrome
HLHS
-underdevelopment of the left side of the heart
Heart disease and immunizations
Infants with heart disease should be immunized according to the current guidelines. Immunization schedules may need to be modified around times of acute illness or surgical procedures.
Temperature after heart surgery
An increase in temperature for 24 to 48 up to 100 F is normal. After 48 hours, infection needs to be assessed for.
Chest tubes:
the largest volume of drainage occurs in the first 12 to 24 hours, and drainage is greater after extensive heart surgery.
Chest tube drainage amounts
Drainage of more than 3mL/kg/hr for more than 3 consecutive hours or 5 to 10 mL/kg in any 1 hour is excessive and my indicate postoperative hemorrhage. Notify the surgeon immediately, since cardiac tamponade can develop rapidly and is life threatening.
Chest tube removal
Usually takes place 1 to 3 days after surgery.
Clinical rheumatic activity
Aschoff bodies are found in virtually all patients with clinical rheumatic activity.
The leading cause of acquired heart disease in children in the U.S. is:
Kawasaki disease
Which heart defect causes hypoxemia and cyanosis because desaturated venous blood is entering the systemic circulation?
Tetralogy of Fallot
