CH 16: Altered Perfusion
A client is being discharged following a percutaneous transluminal coronary angioplasty (PTCA) with stent placement. The nurse explains that the acetylsalicylic acid (ASA) and clopidogrel are both prescribed to reduce the risk of which complication?
stent occlusion Explanation: Antiplatelet treatment with both ASA and clopidogrel are recommended for 1 year after stent placement to prevent thrombosis, which can lead to stent occlusion, a major risk of the procedure. Anticoagulants, not antiplatelet medications are used to prevent pulmonary embolism or cardioembolic stroke, and neither of these conditions are a complication of PTCA. Stent collapse is not a known issue after PTCA and antiplatelet medications would not affect stent collapse.
A client is rushed to the emergency department with assessment findings of urticaria, wheezing, chest tightness, and difficulty breathing. The client is most likely experiencing which type of shock?
Anaphylactic Explanation: Signs and symptoms associated with impending anaphylactic shock include abdominal cramps; apprehension; warm or burning sensation of the skin; itching; urticaria (i.e., hives); coughing; choking; wheezing; chest tightness; and difficulty in breathing. The other types of shock do not have these clinical manifestations.
A 56-year-old male client has been diagnosed with hypercholesterolemia. Which laboratory result supports this diagnosis?
Cholesterol 250 mg/dL (6.47 mmol/L) and HDL 32 mg/dL (0.83 mmol/L) Explanation: A diagnosis of hypercholesterolemia would be made based on a cholesterol level greater than 200 mg/dL (5.18 mmol/L) and an HDL of greater than 30 mg/dL (0.78 mmol/L).
A client is immobilized following a hip injury. The client has developed lower leg discoloration with edema, pain, and tenderness in the midcalf area. How should the nurse document these clinical findings?
Deep vein thrombosis Explanation: Venous insufficiency with deep vein thrombus formation is characterized by pain, swelling [edema], and deep muscle tenderness. Fever, general malaise, and elevated white blood cell count and erythrocyte sedimentation rate are accompanying indications of inflammation. Swelling may vary from minimal to maximal. Immobility raises the risk for thrombus formation. The skin is intact, so venous stasis ulcerations are not present. Distended torturous veins (varicosity manifestations) are not present with deep vein thrombosis.
A nurse is administering morning medications to a number of clients on a medical unit. Which medication regimen is most suggestive that the client has a diagnosis of heart failure?
Diuretic, ACE inhibitor, beta-blocker Explanation: Diuretics, ACE inhibitors, and beta-blockers are all commonly used in the treatment of heart failure. Antiplatelet aggregators, calcium and potassium supplements, and anticoagulants are less likely to relate directly to a diagnosis of heart failure.
About a week after dental cleaning and root canal, a client has developed an infection of the thin, three-layered membrane that lines the heart and covers the valves. What is this client's most likely diagnosis?
Endocarditis Explanation: The endocardium is a thin, three-layered membrane that lines the heart and covers the valves; infection of this part of the heart is consequently referred to as endocarditis. Pericarditis represents an inflammatory process of the pericardium. Myocarditis is the inflammation of the myocardium. Vasculitis is the inflammation of the blood vessels.
A client with malignant hypertension is at risk for a hypertensive crisis, including the cerebral vascular system often causing cerebral edema. The nurse would assess this client for which signs and symptoms?
Headache and confusion Explanation: Cerebral vasoconstriction probably is an exaggerated homeostatic response designed to protect the brain from excesses of blood pressure and flow. The regulatory mechanisms often are insufficient to protect the capillaries, and cerebral edema frequently develops. As it advances, papilledema (i.e., swelling of the optic nerve at its point of entrance into the eye) ensues, giving evidence of the effects of pressure on the optic nerve and retinal vessels. The client may have headache, restlessness, confusion, stupor, motor and sensory deficits, and visual disturbances. In severe cases, convulsions and coma follow. Lethargy, nervousness, and hyperreflexia are not signs or symptoms of cerebral edema in malignant hypertension.
A nurse is teaching a client with newly diagnosed hypertension about antihypertensive drug therapy. The nurse determines that the knowledge is understood when the client correctly describes which of the following as the mechanism of action of an angiotensin-converting enzyme (ACE) inhibitor?
Inhibits the conversion of angiotensin I to angiotensin II, decreasing angiotensin II levels and reducing its effect on vasoconstriction Explanation: The ACE inhibitors act by inhibiting the conversion of angiotensin I to angiotensin II, thus decreasing angiotensin II levels and reducing its effect on vasoconstriction.
A 20-year-old college student being treated for a kidney infection developed a temperature of 104ºF (40°C) in spite of treatment with antibiotics. Her pulse was high, her blood pressure was low, and her skin was hot, dry, and flushed. The nurse knows that this client most likely is experiencing which type of shock?
Septic Explanation: Septic shock can result with the body's response to a severe infection. Neurogenic shock is a loss of sympathetic (adrenergic) control of systemic blood vessel tone. Cardiogenic shock is a loss of cardiac efficiency, and anaphylactic shock is a severe allergic reaction.
A client comes to the emergency room with all the symptoms of a myocardial infarction. Which lab value, known to have a high specificity for myocardial tissue considered the primary biomarker test for diagnosing an MI, does the nurse suspect the physician will order?
Troponin assays Explanation: The troponin assays have high specificity for myocardial tissue and have become the primary biomarker for the diagnosis of myocardial infarction. Creatine kinase is an intracellular enzyme found in muscle cells. The troponin level identifies necrosis in cardiac muscles earlier than creatine kinase. The others are not necessarily used when suspecting a myocardial infarction.
The health care team is developing a plan of care for a client diagnosed with congestive heart failure (CHF). The primary treatment goal would be:
improving quality of life by relieving symptoms. Explanation: A primary treatment goal for a client with CHF is to improve the quality of life through symptom management. CHF will not be cured, and maintaining a higher oxygen level will assist with dyspnea associated with CHF. A stent is not an option for treatment of CHF.
A client with heart failure asks, "Why am I taking a 'water pill' when it's my heart that is having a problem?" While educating the client about the Frank-Starling mechanism, which explanation is most appropriate to share?
"Since your heart is not pumping efficiently, the kidneys are getting less blood flow; therefore, the kidneys are holding on to sodium and water." Explanation: In heart failure with a reduced ejection fraction, a decrease in cardiac output and renal blood flow leads to increased sodium and water retention by the kidney with a resultant increase in vascular volume and venous return to the heart and an increase in ventricular end-diastolic volume. Drinking water may increase volume but is not the physiologic reason for retention of fluid. Diuretics do decrease weight as a result of diuresis, but weight loss is not the purpose for giving diuretics. The lungs are not the primary cause of heart failure.
A client has just been diagnosed with hypercholesterolemia and is asking what treatment will be needed. About which topics should the nurse educate the client? Select all that apply.
-Smoking cessation -Dietary measures to reduce LDL levels -Weight reduction if overweight Explanation: The management of hypercholesterolemia focuses on dietary and therapeutic lifestyle changes; when these are unsuccessful, pharmacologic treatment may be necessary. Therapeutic lifestyle changes include an increased emphasis on physical activity, dietary measures to reduce LDL levels, smoking cessation, and weight reduction for people who are overweight. Increased intake of fats and sodium would cause weight gain and hypertension and result in a negative consequence.
Coronary artery bypass grafting (CABG) is a treatment modality for which disorder of cardiac function?
Atherosclerosis and unstable angina Explanation: Coronary artery bypass grafting (CABG) may be the treatment of choice for people with significant coronary artery disease (CAD) who do not respond to medical treatment and who are not suitable candidates for percutaneous coronary intervention. CABG does not address valve disorders, pericardial effusion, or cardiomyopathies.
The student attends a health fair and has his serum cholesterol checked. He has a high lipoprotein level (LDL). He understands which of the following about LDL cholesterol?
It is believed to play an active role in the pathogenesis of the atherosclerotic lesion. Explanation: Hyperlipidemia, particularly LDL, with its high cholesterol content, is also believed to play an active role in the pathogenesis of the atherosclerotic lesion. Dietary cholesterol tends to increase LDL cholesterol. HDL participates in the reverse transport of cholesterol by carrying cholesterol from the peripheral tissues back to the liver.
A client has just returned from his surgical procedure. During initial vital sign measurements, the nurse notes that the client's heart rate is 111 beats/minute and the BP is 100/78 (borderline low). In this early postoperative period, the nurse should be diligently monitoring the client for the development of:
hypovolemic shock due to acute intravascular volume loss. Explanation: Hypovolemic shock is characterized by diminished blood volume such that there is inadequate filling of the vascular compartment. Hypovolemic shock also can result from an internal hemorrhage or from third-space losses, when extracellular fluid is shifted from the vascular compartment to the interstitial space or compartment, without fluid movement in/out of the cells. Within seconds after the onset of hemorrhage or the loss of blood volume, compensatory manifestations of tachycardia, vasoconstriction, and other signs of sympathetic and adrenal medullary activity appear. There is no indication that this client has developed a pulmonary embolism, is having side effects from versed administration, or is going into renal failure due to an overdose of medication.
A client reports severe indigestion that has been intermittent; however, the pain is now constant and feels like a vise. The nurse does an ECG and recognizes that the situation is possibly emergent due to ST-segment elevation, which could indicate:
myocardial infarction. Explanation: The ST-segment elevation with myocardial infarction could be caused by a decrease in blood supply to that area of cardiac muscle. Hypokalemia results in flattening or inversion of T waves.
A client awaiting a heart transplant is experiencing decompensation of the left ventricle that will not respond to medications. The health care provider (HCP) suggests placing the client on a ventricular assist device (VAD). The client asks what this equipment will do. Which response most accurately describes the purpose of a VAD?
"Decreases the workload of the myocardium while maintaining cardiac output and systemic arterial pressure." Explanation: Although the response is technical in nature, it is the most accurate. The nurse will use the most accurate terms and then follows up with an explanation of these terms based on the client's level of understanding of the terminology. Decompensated, refractory heart failure reflects deterioration in cardiac function that is unresponsive to medical or surgical interventions. Ventricular assist devices (VADs) are mechanical pumps used to support ventricular function. VADs are used to decrease the workload of the myocardium while maintaining cardiac output and systemic arterial pressure. This decreases the workload on the ventricle and allows it to rest and recover. The rest of the distractors relate to the monitoring in an ICU of cardiac functioning. Invasive hemodynamic monitoring may be used for assessment in acute, life-threatening episodes of heart failure. With the balloon inflated, the catheter monitors pulmonary capillary pressures (i.e., pulmonary capillary wedge pressure or pulmonary artery occlusion pressure), which reflect pressures from the left ventricle. The pulmonary capillary pressures provide a means of assessing the pumping ability of the left ventricle. One type of pulmonary artery catheter is equipped with a thermistor probe to obtain thermodilution measurements of cardiac output.
Chronic stable angina, associated with inadequate blood flow to meet the metabolic demands of the myocardium, is caused by:
Fixed coronary obstruction Explanation: Chronic stable angina is caused by fixed coronary obstruction that produces an imbalance between coronary blood flow and the metabolic demands of the myocardium. Endothelial relaxing factors relax the smooth muscle in the vessel wall and allow increased blood flow; treatment for chronic stable angina is with a vasodilating agent, such as nitroglycerine, that relaxes the vessels and enhances coronary blood flow. Intermittent vessel vasospasms, in conjunction with coronary artery stenosis, cause the vasospastic type of angina. Increased formation of collateral vessels is a compensatory response that allows adequate blood circulation to tissues distal to an obstruction.
The pathophysiology of heart failure involves an interaction between decreased pumping ability and the ________ to maintain cardiac output.
compensatory mechanisms Explanation: The pathophysiology of heart failure involves an interaction between two factors: a decrease in pumping ability of the heart with a consequent decrease in the cardiac reserve and the compensatory mechanisms that serve to maintain the cardiac output while also contributing to the progression of heart failure. Myocardial muscle hypertrophy has an important role in long-term adaptation to hemodynamic overload. Stimulation of the sympathetic nervous system plays an important role in the compensatory response to decreased cardiac output and to the pathogenesis of heart failure. Heart failure is a muscle contractility problem, unrelated to the electrical conduction that stimulates it.