Lecture 4 Problems related to the production and circulation of blood

Question 1

Three determinants of cardiac output

Answer 1

Preload, afterload, and contractility.

Question 2

The best indicator of cardiac output in pediatric patients

Answer 2

The pedal pulse.

Question 3

Pediatric indicators of cardiac dysfunction

Answer 3

Poor feeding
Tachypnea/tachycardia
Failure to thrive/poor weight gain/activity intolerance 
Developmental delays
Prenatal history
Family history of cardiac disease

Question 4

Increased pulmonary blood flow (“acyanotic”)

Answer 4

Symptoms of CHF
Feeding Difficulties
Respiratory rate of 60 or above = Gavage, because feeding will tire the patient out.
If untreated, irreversible pulmonary hypertension
Defects: Patent ductus arteriosus (PDA), atrial septal defect (ASD), ventricular Septal Defect (VSD), atrioventricular canal (AV canal)

Question 5

Atrioventricular canal (AV canal) has a strong association with _

Answer 5

Trisomy 21 (Down syndrome).

Question 6

Patent ductus arteriosus (PDA)

Answer 6

1. Failure of the ductus arteriosus (fetal shunt that enables blood to bypass the lungs) to close, causes oxygenated blood to spill from the aorta back to the pulmonary artery - increased pulmonary blood flow.
2. Can be closed surgically - placement of occluder device.

Question 7

Atrial septal defect (ASD)

Answer 7

1. Failure of the foramen ovale (fetal shunt that enables blood to flow directly from the right atrium to the left atrium) to close or failure of the septum between the atria to develop. Causes blood to spill from the left atrium back to the right atrium - increased pulmonary blood flow.
2. Can be closed surgically - placement of occluder device.

Question 8

Ventricular septal defect (VSD)

Answer 8

Causes blood to spill from the left ventricle to the right atrium - increased pulmonary blood flow. Causes problems earlier than PDA or ASD.

Question 9

Atrioventricular canal (AV canal).

Answer 9

1. “Wide open heart” - similar to VSD but much more blood spills from the left to right side, with one large common AV valve.
2. Old name: Endocardial cushion defect.

Question 10

Pulmonary artery band

Answer 10

Surgical intervention to restrict the flow of blood to the pulmonary artery using a Dacron band. Not corrective - palliative, used to “buy time”.

Question 11

Decreased pulmonary blood flow (“cyanotic”)

Answer 11

1. Failure to oxygenate blood - O2 Sats of 50-90% - does not respond well to oxygen; dusky, mottled or cyanotic; fatigue, exertional dyspnea; difficulty breathing and eating at same time; chronic - clubbing of fingers and toes, delayed developmental milestones.
2. Compensatory polycythemia - clotting abnormalities, sluggish blood flow in lungs with small pulmonary infarcts.
3. Defects: Pulmonary stenosis, pulmonary atresia, tetralogy of Fallot, triscuspid atresia.
4. Increased risk for CVA and endocarditis.

Question 12

Tetralogy of Fallot

Answer 12

1. Four defects: A VSD, overriding aorta, right ventricular hypertrophy, and pulmonary stenosis.
2. Tet spells: Hypercyanotic episodes during crying or feeding. Knee-chest position: Can relieve the cyanosis - physiologically reduces the shunting of blood.
3. Palliative treatment: Surgical shunt - improves blood flow to the lungs.
4. Prostaglandins:

Question 13

Triscuspid atresia

Answer 13

A nonexistent triscupid valve, results in decreased pulmonary blood flow.

Question 14

Obstruction to systemic blood flow

Answer 14

1. Symptoms of low cardiac output: Diminished pulses, poor color, poor capillary refill, decreased urinary output, decreased flow to GI tract, CHF with pulmonary edema.
2. Defects: Coarctation of the aorta, aortic stenosis

Question 15

Coarctation of the aorta

Answer 15

1. A “crimp” in the main portion of the descending aorta.
2. Younger children: BP discrepancies, pulse discrepancies. Older children: Hypertension in upper extremities; dizziness, headache, fainting or epistaxis; decreased or absent pulses in lower extremities; leg cramps during exercise; rib notching on chest X-ray.
3. Surgical repair focuses on relieving the striation - subclavian angioplasty.

Question 16

Mixed/combined congenital heart defects

Answer 16

Defects: Transposition of the great arteries (TGA), hypoplastic left heart syndrome (HLHS), truncus arteriosus.

Question 17

Transposition of the great arteries (TGA)

Answer 17

Parallel blood flow, results in mixed blood.

Procedure of choice: Arterial switch.

Question 18

Hypoplastic left heart syndrome (HLHS)

Answer 18

4th most common congenital cardiac defect
Treatment - 4 options: Comfort care only, heart transplant early, 3-stage palliative surgical procedure, the first of which is called the Norwood procedure
Hybrid Procedure for HLHS/staged

Question 19

What term is defined as the volume of blood ejected by the heart in 1 minute?

Answer 19

Cardiac output. [Cardiac output is defined as the volume of blood ejected by the heart in 1 minute. Cardiac output = Heart rate x Stroke volume. Afterload is the resistance against which the ventricles must pump when ejecting blood. Stroke volume is the amount of blood ejected by the heart in any one contraction.]

Question 20

A cardiac defect that allows blood to shunt from the (high pressure) left side of the heart to the (lower pressure) right side can result in which condition?

Answer 20

Congestive heart failure. [As blood is shunted into the right side of the heart, there is increased pulmonary blood flow and the child is at high risk for heart failure. Cyanosis usually occurs in defects with decreased pulmonary blood flow. Bounding upper extremity pulses are a manifestation of coarctation of the aorta.]

Question 21

On an ECG, a bundle branch block would manifest as _

Answer 21

An elongated QRS complex.

Question 22

ECG components

Answer 22

P wave = depolarization of the atria.
QRS complex = depolarization of the ventricles.
T wave = repolarization of the ventricles.

Question 23

Sildenafil (Viagra) can be used to prevent _

Answer 23

Pulmonary hypertension.

Question 24

Medications that enhance cardiac output

Answer 24

1. Furosemide (Lasix) or other diuretics -decrease preload.
2. Digoxin (Lanoxin) - Cardiac glycoside - increase contractility, decrease heart rate.
3. Captopril/Enalapril - Ace inhibitor - decrease afterload

Question 25

Digoxin

Answer 25

Apical pulse - must be at least:
Infants: 90-110 bpm.
Older children: 70 bpm.
Adults: 60 bpm.

Question 26

Rheumatic fever and rheumatic heart disease

Answer 26

An inflammatory disease of the heart, joints, and central nervous system that follows a streptococcal infection.

Question 27

Kawasaki disease

Answer 27

Acute systemic vasculitis of unknown cause
Self-limited; resolves in 6-8 weeks
Without treatment, 20-25% will develop cardiac sequelae
Increased potential for MI.
IVIG and aspirin.
3 stages = Acute, subacute, and convalescent.

Question 28

Sickle cell anemia

Answer 28

Autosomal recessive
Primarily affects African-Americans
HgbA/HgbSS
Causes of decreased oxygen tension
Infection
Dehydration
Exposure to cold
Physical or emotional stress
High altitudes

Question 29

Sickle cell crisis

Answer 29

Vaso-occlusive crisis (painful episode or pain crisis)
Sequestration crisis
Cerebrovascular accident
Chest syndrome
Chest pain, fever, cough, dyspnea
Overwhelming infection
Assess risk for stroke, increase hydration, increased risk for infection.

Question 30

Hemophilia

Answer 30

No aspirin

Factor replacement therapy

Question 31

After returning from cardiac catheterization, the nurse determines that the pulse distal to the catheter insertion site is weaker. How should the nurse respond?

Answer 31

Record data on the assessment flow record. [The pulse distal to the catheterization site may be weaker for the first few hours after catheterization but should gradually increase in strength. Documentation of the finding provides a baseline. The extremity is maintained straight for 4 to 6 hours.]

Question 32

The nurse is caring for a school-age girl who has had a cardiac catheterization. The child tells the nurse that her bandage is “too wet.” The nurse finds the bandage and bed soaked with blood. What nursing action is most appropriate to institute initially?

Answer 32

Apply direct pressure above the catheterization site. [When bleeding occurs, direct continuous pressure is applied 2.5 cm (1 inch) above the percutaneous skin site to localize pressure on the vessel puncture. The physician can be notified, and a new bandage with more pressure can be applied after pressure is applied. The nurse can have someone else notify the physician while the pressure is being maintained.]

Question 33

Heart failure

Answer 33

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. HF is not a disease but rather a result of the inability of the heart to pump efficiently. HF occurs most frequently secondary to congenital heart defects in which structural abnormalities result in increased volume load or increased pressures on the ventricles.

Question 34

The nurse finds that a 6-month-old infant has an apical pulse of 166 beats/ min during sleep. What nursing intervention is most appropriate at this time?

Answer 34

Report data to the practitioner. [One of the earliest signs of HF is tachycardia (sleeping heart rate >160 beats/min) as a direct result of sympathetic stimulation. The practitioner needs to be notified for evaluation of possible HF.]

Question 35

A 2-year-old child is receiving digoxin (Lanoxin). The nurse should notify the practitioner and withhold the medication if the apical pulse is less than which rate?

Answer 35

90 beats/min. [If a 1-minute apical pulse is less than 90 beats/min for an infant or young child, the digoxin is withheld. 60 beats/min is the cut-off for holding the digoxin dose in an adult.]

Question 36

What nursing consideration is important when suctioning a young child who has had heart surgery?

Answer 36

Administer supplemental oxygen before and after suctioning. [When suctioning is indicated, supplemental oxygen is administered with a manual resuscitation bag before and after the procedure to prevent hypoxia. Suctioning should be done only as indicated and very carefully to avoid vagal stimulation. The child should be suctioned for no more than 5 seconds at a time.]

Question 37

The nurse notices that a child is increasingly apprehensive and has tachycardia after heart surgery. The chest tube drainage is now 8 ml/kg/hr. What should be the nurse’s initial intervention?

Answer 37

Notify the practitioner of these findings. [The practitioner is notified immediately. Increases of chest tube drainage to more than 3 ml/kg/hr for more than 3 consecutive hours or 5 to 10 ml/kg in any 1 hour may indicate postoperative hemorrhage. Increased chest tube drainage with apprehensiveness and tachycardia may indicate cardiac tamponade—blood or fluid in the pericardial space constricting the heart—which is a life-threatening complication.]

Question 38

What sign/symptom is a major clinical manifestation of rheumatic fever (RF)?

Answer 38

Polyarthritis. [Polyarthritis, which is swollen, hot, red, and painful joints, is a major clinical manifestation. The affected joints will change every 1 or 2 days. The large joints are primarily affected. Fever is considered a minor manifestation of RF. Osler nodes and Janeway spots are characteristic of bacterial endocarditis.]

Question 39

When caring for the child with Kawasaki disease, what should the nurse know to provide safe and effective care?

Answer 39

Therapeutic management includes administration of gamma globulin and salicylates. [High-dose intravenous gamma globulin and salicylate therapy are indicated to reduce the incidence of coronary artery abnormalities when given within the first 10 days of the illness. Aspirin is part of the therapy. Mucous membranes, conjunctiva, changes in the extremities, and cardiac involvement are seen. The fever of Kawasaki disease is unresponsive to antibiotics. It is responsive to anti-inflammatory doses of aspirin and antipyretics.]

Question 40

The nurse is giving discharge instructions to the parent of a 6-year-old child who had a cardiac catheterization 4 hours ago. What statement by the parent indicates a correct understanding of the teaching?

Answer 40

“I should change the bandage every day for the next 2 days.” [The child should avoid strenuous exercise but can go back to school. The child should avoid a tub bath, but an older child could take a shower the first day after the catheterization. The site should not have swelling or redness; if there is, it should be reported to the health care practitioner.]

Question 41

Heart failure (HF) is a problem after the child has had a congenital heart defect repaired. The nurse knows a sign of HF is what?

Answer 41

Wheezing. [A clinical manifestation of heart failure is wheezing from pulmonary congestion. The blood pressure decreases, urine output decreases, and heart rate increases.]

Question 42

A 1-year-old has been admitted for complete repair of a tetralogy of Fallot. What assessment finding should the nurse expect to be documented?

Answer 42

Increasing cyanosis.

Question 43

An infant is diagnosed with transposition of the great vessels. Prostaglandin E1 is given intravenously. The parents ask how long the child will remain on the prostaglandin E1. What is the appropriate response by the nurse?

Answer 43

Prostaglandin E1 will be given continuously until corrective surgery is performed. [To provide intracardiac mixing for a child with transposition of the great arteries, intravenous prostaglandin E1 is administered continuously to keep the ductus arteriosus open to temporarily increase blood mixing and provide an oxygen saturation of 75% or to maintain cardiac output until surgery. It is discontinued after surgery.]

Question 44

Treatment for infective endocarditis

Answer 44

IV penicillin - high doses for 2-8 weeks to completely eradicate the infective organism.

Question 45

A child is recovering from Kawasaki disease (KD). The child should be monitored for which?

Answer 45

ECG changes. [The most serious complication of KD is the development of coronary artery aneurysms and the potential for myocardial infarction in children with aneurysm formation. The nurse should monitor any ECG changes.]

Question 46

A child with sickle cell anemia (SCA) develops severe chest and back pain, fever, a cough, and dyspnea. What should be the first action by the nurse?

Answer 46

Notify the practitioner because chest syndrome is suspected.

Question 47

In a child with sickle cell anemia (SCA), adequate hydration is essential to minimize sickling and delay the vasoocclusion and hypoxia-ischemia cycle. What information should the nurse share with parents in a teaching plan?

Answer 47

Check for moist mucous membranes. [Children with SCA have impaired kidney function and cannot concentrate urine. Parents are taught signs of dehydration and ways to minimize loss of fluid to the environment. Encouraging drinking is not specific enough for parents. The nurse should give the parents and child a target fluid amount for each 24-hour period.]

Question 48

What statement is descriptive of most cases of hemophilia?

Answer 48

X-linked recessive inherited disorder in which a blood clotting factor is deficient. [The inheritance pattern in 80% of all the cases of hemophilia is X-linked recessive. The two most common forms of the disorder are factor VIII deficiency (hemophilia A, or classic hemophilia) and factor IX deficiency (hemophilia B, or Christmas disease).]

Question 49

Normal hemoglobin and hematocrit for a child

Answer 49

Hemoglobin: 11.5 to 15.5 g/dL.
Hematocrit: 35% to 45%.