The child with cardiovascular Dysfunction Chapter 25

Signs and symptoms of Hypertension

*Adolescents and Older Children*- Frequent HA, Dizziness, Changes in Vision. *Infants or young children*- Irritability, Head banging or head rubbing, waking up screaming in the night.

Jones Criteria

*Major Manifestations*: -Carditis -Polyarthritis -Erythema Marginatum -Chorea (one of the most disturbing and frustrating manifestations of the disease. Can be mistaken for nervousness, clumsiness, behavioral changes, inattentiveness, and learning disability. *Of utmost importance is stressing to parents and schoolteachers the involuntary, sudden nature of the movements; that it is transitory and that all manifestations will disappear*. -Subcutaneous Nodes *Minor Manifestations*: -Arthralgia, fever, elevated ESR, CRP, Prolonged PR interval

Types of incisions used by a cardiac surgeon.

*Median sternotomy*- most common, follows the sternum down the center of the chest. *ministernotomy*- opens the lower sternum. *Thoracotomy*- Most uncomfortable b/c it goes through an incision from under the arm around the back to the scapula. More painful d/t incision traveling through musculature.

Bradydysrhythmia

*sinus bradycardia* (slower than normal rate) in children can be attributed to the influence of the autonomic nervous system, as with hypervagal tone,or in response to hypoxia and hypotension. -*complete AV block*- aka complete heart block; can be congenital (children with structurally normal hearts) or acquired after surgery to repair cardiac defects. Most commonly related to edema around the conduction system and resolve without treatment. -Temporary epicardial wires are placed in most patients at surgery; if a rhythm disturbance occurs, temporary pacing can be used. -Some children may need a permanent pacemaker. (Pacemaker has a pule generator which consists of the battery and electronic circuitry, and a lead which is a flexible wire that conducts the electrical impulse from the pulse generator to the heart.)

Diagnostic evaluation of Dysrhythmias

-An initial nursing responsibility is recognition of an abnormal heartbeat, either in rate or rhythm. -When suspected, take apical for 1 full minute and compare with the radial rate. Consistently high or low rates should be regarded as suspicious. -place on 12 lead ECG -The basic diagnostic procedure is the ECG, including 24-hour Holter monitoring.

Therapeutic management of Infective Endocarditis

-Appropriate and high dose ABX for 2-8 weeks. -Periodic blood cultures. -Treatment of streptococcal tansillitis and pharyngitis. -Prevention involves administration of prophylactic ABX 1 hour before certain procedures that are associated with the risk of entry of organisms _in very high-risk patients_. Drugs of choice for prophylaxis: amoxicillin, ampicillin, clindamycin, cephalexin, cefadroxil, azithromycin, and clarithromycin. -Treatment of endcarditis requires long-term parenteral drug therapy. -Important to maintain the highest level of oral health and to report any unexplained fever, weight loss, or change in behavior (lethargy, malaise, anorexia) to the practitioner.

Therapeutic management of PA HTN

-Avoid situations that may exacerbate the disease (exercise and high altitudes). -Anticoagulation with coumadin -Vasodilator therapy can prolong survival of patients. Oral CCBs. For those who dont respond in vasodilator testing, *bosentan* (endothelin-receptor antagonist) is available and reduces pulmonary artery pressure and resistance and is safe and well tolerated in children.

Diagnosing HTN

-BP readings should be regular with children older than 3. Children younger than 3 should get BP readings if they have a high risk family history or individual risk factors. -No definitive cutoff values are used in the diagnosis of HTN in the pediatric patient. -Before a DX of HTN is made, BP should be measured on at least three seperate occasions. -Ambulatory BP monitor may be needed if "white-coat HTN" is suspected.

Therapeutic management of Cardiomyopathy

-Correcting underlying cause. -Digoxin, diuretics, and aggressive use of afterload reduction agents are helpful in dilated cardiomyopathy. -Digoxin and inotropic agents are usually not helpful in the other forms of cardiomyopathy b/c increasing the force of contraction may exacerbate the muscular obstruction and actually impair ventricular ejection. -Beta blockers and CCBs have been used to reduce L ventricular outflow obstruction and improve diastolic filling in those with hypertrophic cardiomyopathy.

Agents that may cause anaphylaxis and the Clinical manifestations of anaphylaxis

-Drugs (ABX, chemotherapeutic agents, radiologic contrast media), latex, foods, venom from bees or snakes, and biologic agents (antisera, enzymes, hormones, blood products). -Symptoms occur within seconds or minutes. The sooner the onset the more severe the reaction. Symptoms of uneasiness, restlessness, irritability, severe anxiety, HA, dzziness, paresthesia and disorientation. Loss of consciousness. Cutaneous signs of flushing ad urticaria are common early signs followed by angioedema, most notable in the eyelids, lips, tongue, hands, feet, and genitalia. -Bronchiolar constriction --> narrowing of the airway; pulmonary edema and hemorrhage. Shock occurs d/t mediator-induced vasodilation, --> capillary permeability and loss of intravascular fluid into the interstitial space.

Clinical manifestations of infective endocarditis

-Insidious onset. -Unexplained fever (low grade intermittent) -Anorexia -Malaise -Weight loss -_Characteristic findings caused by extracardiac emboli formation_: -*Splinter Hemorrhages* (thin black lines) under nails. -*Osler nodes* (red, painful intradermal nodes found on pads of phalanges) -*Janeway lesions* (painless hemorrhagic areas on palms and soles). -petechiae on oral mucous membranes.

Monitoring fluids in the postoperative period.

-Intake and output of *all* fluids must be accurately calculated. (including fluid used to flush lines). - Renal failure is a potential risk from a transient period of low cardiac output. (signs of renal failure are decreased urinary output; <1ml/kg/hr and elevated levels of BUN and creatinine). -Fluids restricted immediately postop to prevent hypervolemia (additional demands on the myocardium--> risk for cardiac failure). -Weights daily.

Treatment of KD

-Patient irritability is perhaps the most challenging problem, child needs a quiet environment that promotes adequate rest. -Frequent assessment for signs of HF: decreased urinary output, gallop rhythm (extra heart sound), Tachycardia, and respiratory distress. -Symptomatic relief: mouth care, lubricating ointments, minimize skin discomfort, etc. -High dose IV gamma globulin (IVGG) along with salicylate therapy. -Aspirin initially given in antiinflammatory dose (80-100mg/kg/day) to control fever and symptoms of inflammation. After the fever subsides aspiring is continued at an antiplatelet dose (3-5mg/kg/day). Low dose aspiring is continued in patients without echocardiographic evidence of coronary abnormalities until the platelet count has returned to normal (6-8 weeks). -If coronary abnormalities develop, salicylate therapy contines indefinitely.

Distributive Shock Characteristics

-Reduction in peripheral vascular resistance. -Profound inadequacies in tissue perfusion. -Increased venous capacity and pooling. -Acute reduction in return blood flow to the heart. -Diminished cardiac output

Hypovolemic shock characteristics

-Reduction in size of vascular compartment -Falling BP -Poor capillary fillin -Low CVP

How to distinguish between pulmonary and cardiac causes of cyanosis in newborns?

1) *Hyperoxia Test*- Infant is placed in a 100% oxygen environment, and blood parameters are monitored. A PaO2 of 100 mm Hg or higher suggests lung disease, and a PaO2 lower than 100 mmHg suggests cardiac disease. 2) An Accurate history 3) Chest radiograph 4) Echocardiogram

What may result from Persistent/chronic cyanosis?

1) *Neurologic complications* a) CVA b) Brain Abscess c)Developmental delays (especially in motor and cognitive development.

How might the presence of cyanosis not accurately reflect arterial hypoxemia?

1) Because both oxygen saturation and the amount of circulating hemoglobin are involved. Ex: Children with severe anemia may not be cyanotic despite severe hypoxemia because the hemoglobin level may be too low to produce the characteristic blue color. Conversely, patients with polycythemia may appear cyanotic despite a near-normal PaO2.

Signs of hypoxemia in infants? (mild, more severe, and severe)

1) Infants with mild hypoxemia may be asymptomatic except for cyanosis and exhibit near-normal growth and development. 2) Infants with more severe hypoxemia may exhibit fatigue with feeding, poor weight gain, tachypnea, and dyspnea. 3) Severe hypoxemia resulting in tissue hypoxia is manifested by clinical deterioration and signs of poor perfusion.

How do hypercyanotic spells generally occur in the hospital setting? Treatment of a Hypercyanotic spell?

1) Often seen during blood drawing or IV insertion, when the child is highly agitated, or after cardiac catheterization. 2) Treatment consists of: -Placing the infant in knee-chest position. -Using a calm comforting approach. -Administering 100% oxygen by blow-by. -Morphine SubQ or IV. (reduces infundibular spasms) -IV fluid replacement and volume expansion. (to keep hct and blood viscosity within acceptable limits --> ↓ risk of CVA) -Repeat morphine administration.

What two physiologic changes occur in the body in response to chronic hypoxemia?

1) _Polycythemia_- and increased number of red blood cells, increases the oxygen-carrying capactiy of the blood. Polycythemia causes and increase in the viscosity of the blood and crowds out clotting factors. (anemia may result in iron deficient states). 2) _Clubbing_- a thickening an flattening of the tips of the fingers and toes, is thought to occur because of chronic tissues hypoxemia and polycythemia.

What are the differentiating signs observed in all stages of shock?

1) degree of tachycardia and perfusion to the extremities, 2) level of consciousness, 3) Blood pressure.

The expected outcomes for preprocedure preparation include:

1) reducing anxiety, 2) improving patient cooperation with procedures, 3) enhancing recovery, 4) developing trust with caregivers, 5) improving long-term emotional and behavioral adjustments after procedures. -The most beneficial preparation strategies usually combine information giving and coping skills training such as conscious breathing exercises, distraction techniques, guided imagery, or other behavioral interventions.

Hypoxia

A _reduction in tissue oxygenation_ that results from low oxygen saturations and PaO2, and *results in impaired cellular processes*.

Cyanosis

A blue discoloration in the mucous membranes, skin, and nail beds of the child with reduced oxygen saturation. Results from the presence of deoxygenated hemoglobin (Hgb not bound to oxygen) in a concentration of 5g/dl of blood. *Usually apparent when arterial oxygen saturations are 80%-85%.* Determination of cyanosis is *subjective*. May vary depending on skin pigment, quality of light, color of the room, or clothing worn by the child.

Hypercyanotic Spells

AKA 'blue spells' or 'tet spells' b/c they are often seen in infants with _tetralogy of Fallot_, and may occur in any child whose heart defect includes obstruction to pulmonary blood flow and communication between the ventricles. -Infundibular spasm decreases pulmonary blood flow and increases R-->L shunting. Infant becomes acutely cyanotic and hyperpneic. Spells rarely occur before 2 months, but generally in the first year. More often in the morning. -Preceded by feeding, crying, defecation, or stressful procedures. -Require prompt assessment and treatment to prevent brain damage or death as they have a sudden onset. -Indicates the need for prompt surgical treatment if possible.

Kawasaki Disease (mucocutaneous lymph node syndrome)

Acute systemic vasculitis of unknown cause. Peak evidence in toddlers. Self limiting. Etiology unknown, however without treatment ~20% of children develop coronary artery dilation or aneurysm formation. -Infants younger than 1 year are most seriously affected by KD and are at the greatest risk for heart involvement. Not spread person to person. -Principal area of concern in KD is the cardiovascular system. -During initial stage, extensive inflammation of the arterioles, venules, and capillaries occurs, causing many of the clinical symptoms. Segmental damage to the medium sized muscular arteries (mainly the coronary arteries) can occur --> formation of coronary artery aneurysm. -When death occurs it is usually the result of MI from coronary thrombosis, or years later from severe scar formation and stenosis in coronary aneurysms.

Frequent causes of cardiogenic shock

After surgery for congenital heart disease Primary pump failure-- myocarditis, myocardial trauma, biochemical derangements, heart failure Dysrhythmias -- Supra ventricular tachycardia, AV block, and ventricular dysrhythmias; secondary to myocarditis or biochemical abnormalities

Electrophysiologic cardiac catherterization

Allows for identification of the conduction disturbance and immediate investigation of drugs that may control the dysrhythmia.

Transesophageal Recording

An electrode is passed to the lower esophagus and when in position at a point proximal to the heart, is used to stimulate and record dysrhythmias.

Most frequent causes of Distributive Shock

Anaphylaxis-Extreme allergy or hypersensitivity to a foreign substance. Sepsis- (Septic shock, bacteremic shock, endotoxic shock)- Overwhelming sepsis and circulating bacterial toxins. Loss of neuronal control (neurogenic shock)-- Interruption of neuronal transmission (spinal cord injury) Myocardial depression and peripheral dilation -- Exposure to anesthesia or ingestion of barbiturates, tranquilizers, opioids, antihypertensive agents, or ganglionic blocking agents

Known causes of *secondary cardiomyopathy*

Anthracycline toxicity, hemochromatosis (excessive iron storage), Duchenne muscular dystrophy, Kawasaki Disease, collagen diseases, and thyroid dysfunction.

Manifestations of Compensated Stage of shock

Apprehensiveness Irritability Unexplained tachycardia Normal blood pressure Narrowing pulse pressure Thirst Pallor Diminished urinary output Reduced perfusion of extremities

When does nursing care of the child with a congenital heart defect begin?

As soon as the diagnosis is suspected. Prenatal diagnosis of congenital heart defects is becoming increasingly frequent.

Why must dehydration be prevented in children with hypoxemia?

Because it potentiates the risk of CVAs.

Why is it difficult to provide adequate nutrition to infants with HF or complex congenital defects?

Because of their high caloric requirements and inability to suck effectively d/t fatigue and tachypnea. The child should be fed at the first sign of hunger (when sucking on fists) rather than waiting until he or she cries for a bottle b/c the stress of crying further exhausts the limited energy supply.

Why is it important to limit the time of deep hypothermic circulatory arrest during infant surgery?

Because there is a higher incidence of neurodevelopmental deficits in children after heart surgery than in the normal population, specifically in speech and language, fine motor skills, and cognitive processes.

Most Frequent causes of Hypovolemic Shock

Blood loss (hemorrhagic shock), GI bleeding, intracranial hemorrhage. Plasma loss- Increased capillary permeability associated with sepsis and acidosis, hypoproteinemia, burns, peritonitis. Extracellular fluid loss- Vomiting, diarrhea, glycosuric diuresis, sunstroke.

Rheumatic Heart Disease

Cardiac valve damage. -The most significant complication of Rheumatic Fever. -Mitral valve is most often affected.

Prostaglandin E1

Causes vasodilation and smooth muscle relaxation --> increasing dilation and patency of the ductus arteriosus. Administered IV to reestablish pulmonary blood flow. -Has proved to be life saving for infants with ductus-dependent cardiac defects.

Hypertrophic Cardiomyopathy

Characterized by an increase in heart muscle mass without an increase in cavity size, usually occurring in the left ventricle and associated with abnormal diastolic filling. -Familial autosomal dominant genetic abnormality, probably the most common genetically transmitted CVD. -Clinical presentation usually appears in school age period or adolescence and may include anginal chest pain, dysrhythmias, and syncope. -ECG demonstrates left ventricular hypertrophy, often with ST-T changes. -The echocardiogram is most helpful and demonstrates asymmetric septal hypertrophy and an increase in left ventricular wall thickness, with a small left ventricle cavity.

Manifestation of Decompensated stage of Shock

Confusion and somnolence Tachypnea Moderate Metabolic Acidosis Oliguria Cool, pale extremities Decreased skin turgor Poor capillary filling

Characteristics of Cardiogenic shock

Decreased Cardiac Output

Systemic Hypertension

Defined as the consistent elevation of BP beyond values considered to be the upper limits of normal. -*Essential HTN*- no identifiable cause. *Secondary HTN*- subsequent to an identifiable cause. Stage 1 HTN- BP between 95th percentile and 99th percentile. Stage 2 HTN- BP readings over the 99th percentile plus 5 mm Hg.

Diagnostic Criteria of KD

Diagnosis is established on the basis of clinical findings and associated laboratory results. Important to note that many children with KD do not fulfill standard diagnostic criteria, *therefore one must consider KD as a possible diagnosis in any child or infant with a prolonged elevated temp that is unresponsive to ABX and is not attributable to another cause.* -Child must have fever for more than 5 days along with four of five clinical criteria (changes in the extremities, Bilateral conjunctival infection (without exudation), Changes in the oral MM, Polymorphous rash, Cervical lymphadenopathy)

Clinical manifestations of pulmonary artery Hypertension

Dyspnea with exercise, chest pain (result of coronary ischemia in the right ventricle from severe hypertrophy), and syncope (reflects limited cardiac output leading to decreased cerebral blood flow). -Dyspnea is the most common symptom and is caused by impaired oxygen delivery. Right sided HF is progressive and when symptoms of venous congestion and edema are present, the prognosis is poor.

Cardiac Dysrhythmias

Dysrhythmias, or abnormal heart rhythms can occur in children with structurally normal hearts, as features of some congenital heart defects, and in patients after surgical repair of congenital heart defects. -Seen in patients with cardiomyopathy and with cardiac tumors. -May occur secondary to metabolic and electrolyte imbalances. -Classified in several ways including HR characteristics, and by the origin of the dysrhythmia in the atria or ventricles. -Can be benign or can cause decreased cardiac output with associated symptoms. Sudden death can occur.

Stages of septic shock

Early stages the patient has chills, fever, and vasodilation with increased CO -> warm flushed skin that reflects vascular tone abnormalities and hyperdynamic warm or hyperdynamic compensated responses. BP and urinary output are normal. -The second stage- normodynamic, cool or hyperdynamic-decompensated stage lasts only a few hours. Skin is cool, but pulses and BP are still normal. Urinary output diminishes, mental state is depressed. -Hypodynamic or cold stage- cardiovascular function progressively deteriorates even with aggressive therapy. Pt has hypothermia, cold extremities, weak pulses, hypotension, and oliguria or anuria. Severely lethargic or comatose. Multiorgan failure is common.

Pathophysiology of Endocarditis

Endocarditis is most likely to occur from routine exposure to bacteremia associated with usual daily activities. -Can also occur after procedures: dental work, cardiac surgery (especially if synthetic material is used (valves, patches, conduits)), or from long term indwelling catheters. -The microorganisms grow on the endocardium and form vegetations (verrucae), deposits of fibrin, and platelet thrombi. -May invade adjacent structures or break off as thrombi.

What is the initial action of the nurse for a child who is in shock?

Ensure adequate tissue oxygenation!!!!!!!!

Therapeutic Management of Rheumatic Fever

Goals of medical management: 1) eradication of hemolytic streptococci, 2) prevention of permanent cardiac damage, 3) palliation of the other symptoms, 4) prevention of recurrences of RF. -Penicillin is drug of choice. -Salicylates are used to control inflammatory process (especially in the joints, and reduce the fever and discomfort). -Bed Rest -Children who have acute RF are susceptible to recurrent RF for the rest of their lives. Recurrent infection must be prevented as it is likely to result in rheumatic heart disease.

Pulmonary Artery Hypertension

Group of rare disorders that result in an elecation of pulmonary artery pressure above 25mm Hg at rest after the neonatal period. -Some evidence suggests a genetic basis - mutations to chromosome 2. -Affects the small pulmonary arteries and is characterized by vascular narrowing leading to an increase in pulmonary vascular resistance. This generally leads to pulmonary vascular remodeling of the pulmonary circulation , characterized by occlusion of the lumen in medium and small pulmonary arteries because of cellular proliferation. -Cardiac causes occur primarily in patients with large L-R shunt --> increased pulmonary blood flow. -Other causes: hypoxic lung disease, thromboembolic diseases causing pulmonary vascular obstruction, collagen vascular diseases, and exposure to toxic substances.

Complications following Heart Transplant

Leading cause of death in the first 3 years after heart transplantation is rejection, with the greatest risk in the first 6 months. -Immunosuppressants must be taken for life and have many systemic side effects. Triple drug therapy: a calcineurin inhibitor (cyclosporine or tacrolimus), steroids, and azathioprine is most commonly used in pediatric patients. -Infection is always a risk. -*Coronary artery disease in the leading cause of death among late survivors of heart transplantation.*

Cardiac Involvement in KD

Long term complications of KD include the development of coronary artery aneurysms, disrupting blood flow. Children with larger aneurysms have the potential for MI d/t thrombotic occlusion of a coronary aneurysm. -Affected arteries dilate progressively reaching their max diameter at ~ 1 month. Over time as the damaged artery tries to heal, stenosis of the aneurysm may develop and lead to MI. _symptoms of MI in children_: abdominal pain, vomiting, restlessness, inconsolable cry, pallor and shock.

Clinical Manifestations of Kawasaki Disease

Manifests in three phases: acute, subacute, and convalescent. Big red eyes, big red lips, bright red tongue. Fine red rash on entire body. *acute phase*- abrupt onset of high fever that is unresponsive to ABX and antipyretics. Child then develops remaining diagnostic symptoms (edema, erythema of the palms and soles). Typically the child is very irritable. *subacute phase*- begins with resolution of the fever and and lasts until all clinical signs of KD have disappeared. (Periungual desquamation (peeling) of the hands and feet). During this phase the child is at greatest risk for the development of coronary artery aneurysms. -Baseline Echocardiogram should be obtained at the time of DX. *Convalescent phase*- all of the clinical signs of KD have resolved, but that laboratory values have not returned to normal. This phase completes when all blood values are normal (6-8 weeks after onset). At the end of this stage the child has regained his or her usual temperment, energy, and appetite.

How should the child's physical activity be restricted?

Most children do not need to restrict activity, and the best approach is to treat the child normally and allow self-limited activity. _Exceptions_ - strenuous recreational and competitive sports in children with specific cardiac problems.

Diagnosing Endocarditis

Most commonly used guidelines for diagnosis use the revised Duke criteria. -Several laboratory findings may suggest IE: 1)ECG changes (prolonged PR interval), 2) radiographic evidence of cardiomegaly, 3) anemia, 4) elevated erythrocyte sedimentation rate, 5) leukocytosis 6) microscopic hematuria. -Vegetations on the valve and abnormal valve function can often be visualized by echocardiography. -*Definitive diagnosis rests on growth and identification of the causative agent in the blood*.

Etiology of Systemic HTN

Most instances of HTN observed in young children occur secondary to a structural abnormality or an underlying pathologic process. -Most common cause of secondary HTN is *renal disease* followed by cardiovascular, endocrine, and some neurologic disorders. -As a rule, the Younger the child and the more severe the HTN, the more likely it is to be secondary. -Higher rates in children whose parents are hypertensive. African Americans have higher incidence of HTN than whites, as well it develops earlier and is frequently more severe.

Are there any differences regarding immunizations in children with heart disease?

No, infants with heart disease should be immunized according to the current guidelines. Immunizations may need to be modified around time of acute illness or surgical procedures. -Also, infants younger than 2 years of age with unrepaired heart defects, cyanotic lesions, pulmonary hypertension, or history of prematurity should receive the vaccine for *respiratory synctial virus monthly during RSV season.*

Bacterial Endocarditis, or subacute bacterial endocarditis

Now commonly referred to as *infective endocarditis*, Is an infection of the inner lining of the heart (endocardium), generally involving the valves. Most often a sequela of bacteremia in children with acquired or congenital anomalies of the heart or great vessels. Especially affects children with valvular abnormalities, prosthetic valves, shunts, recent cardiac surgery with invasive lines, and rheumatic heart disease with valve involvement. -most common causative agents are staphylococcus aureus and streptococcus viridans. As well as candida albicans.

Cholesterol Triglycerides

Part of the lipoprotein complex in plasma that is essential for cellular metabolism. Triglycerides are natural fats synthesized from carbohydrates, and are used for energy. -Both are major lipids, transported on lipoproteins (a combination of lipids and proteins which include LDL and HDL).

Rheumatic Fever

Poorly understood inflammatory disease that occurs after infection with group A B-Hemolytic streptococcal pharyngitis. -Self limiting, rarely occurs in adults, and affects the joints, skin, brain, serous surfaces and heart.

Therapeutic management of Anaphylaxis

Provide Ventilation Restore adequate circulation Prevent further exposure by identifying and removing the cause when possible. Mild reaction can be managed by subQ antihistamines (benadryl). In moderate to severe cases and with all shock states, *establishing an airway is the first concern*. Ensure ventilation with HOB elevated, unless contraindicated by hypotension.

Chest tubes in the postoperative period.

Purpose is to remove secretions and air to allow reexpansion of the lung. Drainage is checked hourly for color and quantity. -Immediately after surgery the drainage may be bright red, but should progress to serious drainage. The largest volume of drainage is in the first 12-24 hours. -removed on the first to third postop day. Removal is a painful and frightening experience. -To remove, the suture holding the tube is cut, and the tubes are quickly pulled out *at the end of full respiration to prevent intake of air into the pleural cavity*. -Purse string suture is used to close the opening. -Petrolatum-covered gauze dressing is applied over wound. -Breath sounds assessed. -Chest radiograph is obtained ( to assess for pneumothorax).

Restrictive Cardiomyopathy

Rare in children. -A Restriction to ventricular filling caused by endocardial or myocardial disease or both. -Characterized by diastolic dysfunction and absence of ventricular dilation or hypertrophy. Symptoms similar to HF.

Hypovolemic shock

Reduced blood flow causes diminishes venous return to the heart, low CVP, low CO, and hypotension. Vasomotor centers in the medulla are signaled, causing a compensatory increase in the force and rate of cardiac contraction and constriction of arterioles and veins, thereby increasing peripheral vascular resistance. At the same time the lowered BV --> release of large amounts of catecholamines, ADH, adrenocorticosteroids, and aldosterone in an effort to conserve body fluids. --> reduced blood flow to the skin, kidneys, muscles, and viscera to shunt the available blood to the brain and heart --> skin feels cold and clammy, poor cap refill and GFR and urinary output are reduced. As a result of impaired perfusion, oxygen is depleted in the tissue cells, causing them to revert to anaerobic metabolism, producing lactic acidosis.--> extra burden on the lungs as they attempt to compensate for the metabolic acidosis by increasing the respiratory rate to remove excess carbon dioxide. Prolonged vasoconstriction results in fatigue and atony of the peripheral arterioles which leads to vessel dilation. Venules remain constricted for a time causing massive pooling in the capillary and venular beds, --> further decreased BV. -CNS hypoperfusion may eventually lead to cerebral edema, cortical infarction, or intraventricular hemorrhage. -Renal hypoperfusion causes renal ischemia with possible tubular or glomerular necrosis and renal vein thrombosis. -Reduced blood flow to the lungs can interfere with surfactant secretion and result in ARDS (characterized by sudden pulmonary congestion and atelectasis with formation of a hyaline membrane). -GI tract bleeding and perforation are always possibilities after splanchnic ischemia and necrosis of intestinal mucosa. -Metabolic complications of shock may include hypoglycemia, hypocalcemia, and other electrolyte disturbances.

Cardiomyopathy

Refers to abnormalities of the myocardium in which the cardiac muscles ability to contract is impaired. -Familial or genetic causes, infection, deficiency states, metabolic abnormalities, and collagen vascular diseases. -Most cardiomyopathies in children are considered primary or idiopathic (cause is unknown).

Hypoxemia

Refers to an arterial oxygen tension (or pressure, PaO2) that is less than normal and can be identified by a decreased arterial saturation or a decreased PaO2.

Heterotrophic heart transplantation

Refers to leaving the recipient's own heart in place and implanting a new heart to act as an additional pump or "piggyback" heart; rarely done in children.

Rest and Activity in the postoperative period.

Rest serves to decrease the workload of the heart and promote healing. -The simplest way to ensure individualized, efficient, high-quality care is to plan at the beginning of the shift the nursing procedures to be done, with periods of rest _identified_. -A _progressive schedule_ of ambulation and activity is planned based on the childs postop activity patterns and posoperative cardiovascular and pulmonary function. -Ambulation is initiated early (~2nd postop day) when all tubes/lines/ventilators have been removed. -Heart rate and Respirations are monitored carefully. -_signs that indicate the need to limit further energy expenditure_: Tachycardia, Dyspnea, Cyanosis, Desaturation, progressive fatigue, and dysrhythmias.

Septic Shock

Sepsis and septic shock are caused by an infectious organism. Widespread activation and systemic release of inflammatory mediators is called the *systemic inflammatory response syndrome*. (SIRS can result from infectious and noninfectious (burns, trauma) causes. -Septic shock is defined as sepsis with organ dysfunction and hypotension.

Tachydysrhythmias

Sinus Tachycardia (Abnormally fast HR), secondary to fever, anxiety, pain, anemia, dehydration, or any other etiologic factor requiring increased cardiac output should be ruled out before diagnosing an increased heart rate as pathologic. -SVT is the most common tachydysrhythmia and refers to a rapid regular HR of 200-300 beats/min. -*Clinical signs in infants and young children are poort feeding, extreme irritability, and pallor.* -*Children may experience palpitations, dizziness, chest pain, and diaphoresis.* _Treatment_: Vagal maneuvers (applying ice to the face, massaging the carotid artery (one side of neck only), or having an older child perform a valsalva maneuver). If this fails--> adenosine by IV push with saline immediately following may be administered. -Radiofrequency ablation has become first line therapy for some types of SVT. A catheter delivering radiofrequency current is directed at the conduction site that has been determined to be the cause, and the area is heated to destroy the tissue.

Prophylactic treatment against Rheumatic Fever (secondary prevention)

Started after acute therapy, consists of monthly IM injections of benzathine penicillin G, two daily oral doses of penicillin, or one daily dose of sulfadiazine. -AHA recommends secondary prophylaxis for all patients diagnose with RF. -Exact length of prophylaxis is base on whether pt has residual heart disease.

How is suctioning performed postoperatively?

Suctioning is performed only as needed and performed carefully as to avoidvagal stimulation (which can trigger cardiac dysrhythmias) and laryngospasm. Suctioning is intermittent and maintained for no more than 5 seconds. -Monitor heart rate after suctioning to detect changes in rhythm or rate, especially bradycardia. Child should be positioned facing the nurse.

Manifestations of Irreversible stage of Shock

Thready weak pulse Hypotension Periodic breathing or apnea Anuria Stupor or coma

Heart Transplantation

Treatment option for infants and children with worsening HF and limited life expectancy despite maximum medical and surgical management. _Indications_: cardiomyopathy and end-stage CHD.

What are the purpose of intracardiac lines in relation to surgery?

Used to measure CVP, may be placed in the right atrium, left atrium, or pulmonary artery. -Allow assessment of pressures inside the cardiac chambers, provide vital information about *volume status, cardiac output, and ventricular function*.

In patients with intracardiac shunting what is the significance of: -Ensuring all IV lines are clear of air. -Placing filters that prevent air from entering IV systems. -Ensuring all connections are taped securely. ?

With intracardiac shunting air that may enter the venous system is then able to go directly to the brain, resulting in an air embolism.

Stages of shock: * Compensated Shock----Decompensated Shock-------Irreversble, or terminal, shock*

_Compensated Shock_- Vital organ function is maintained by intrinsic compensatory mechanisms; blood flow is usually normal or increased but generally uneven or maldistributed in the microcirculation. _Decompensated Shock_- Efficiency of the cardiovascular system gradually diminishes until perfusion in the microcirculation becomes marginal despite compensatory adjustments. The outcomes of circulatory failure that progress beyond the limits of compensation are tissue hypoxia, metabolic acidosis, and eventual dysfunction of all organ systems. _Irreversible or Terminal Shock_- Damage to vital organs, such as the heart or brain, is of such magnitude that the entire organism will be disrupted regardless of therapeutic intervention. Death occurs even if cardiovascular measurements return to normal levels with therapy.

What are expected and unexpected findings regarding vital signs postoperatively?

_Expected_: Heart rate increased. -Temperature changes are typical during the early postoperative period. Hypothermia is expected immediately after surgery from hypothermia procedures, effects of anesthesia, and loss of body heat to the cool environment. (keep child warm to prevent additional heat loss, infants may be placed under a radiant heat warmer). The following 24-48 hours the body temp may rise to 100F as part of the inflammatory response to tissue trauma. _Unexpected_: Diminished or absent breath sounds (may indicate atelectasis or a pleural effusion or pneumothorax). Dysrhythmias may occur postop secondary to anesthetics, acid-base and electrolyte imbalance, hypoxia, surgical intervention, or trauma to conduction pathways.

Shock

aka Circulatory Failure, is a complex clinical syndrome characterized by inadequate tissue perfusion to meet the metabolic demands of the bod, resulting in cellular dysfunctions and eventual organ failure. -Causes may be different but the physiologic consequences are the same and include hypotension, tissue hypoxia, and metabolic acidosis. -circulatory failure in children is a result of hypovolemia, altered peripheral vascular resistance, or pump failure. -The CO and distribution to the various body tissues can change rapidly in response to intrinsic (myocardial and intravascular) or extrinsic (neuronal) control mechanisms.

Dilated cardiomyopathy

characterized by ventricular dilation and greatly decreased contractility, resulting in symptoms of HF. -Most common type of cardiomyopathy. -Clinical findings: tachycardia, dyspnea, hepatosplenomegaly, fatigue, and poor growth.

Orthopic heart transplantation

refers to removing the recipients own heart and implanting a new heart from a donor who has had brain death but a healthy heart. The donor and recipient are matched by weight and blood type.