Chapter 6 Care of the Patient Experiencing Shock or Heart Failure

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Understanding the Essentials of

CRITICAL CARE Nursing

Understanding the Essentials of Critical Care NursingKathleen Ouimet Perrin

Chapter 6Care of the Patient Experiencing Shock or Heart Failure




Learning Outcome 1




Hypvolemia

•Results from decreased circulating volume

•Loss of 15–30 % or more of normal blood volume




Etiology

•Hemorrhage– GI bleed, trauma, surgery, ruptured aneurysm

•Fluid loss– Vomiting, diarrhea, burns




Clinical Manifestations

•Hypotension

•Orthostatic

•Tachycardia

•Reduced capillary refill

•Dry mucous membranes

•Poor skin turgor




Clinical Manifestations (cont.)

•Thirst

•Weight loss

•Oliguria

•Concentrated urine

•Altered mental status




Diagnostic Criteria

•Reviews laboratory studies for:– Hypernatremia (serum levels above 145

mEq/L)– Increased hematocrit (Hct) due to

hemoconcentration (if patient actively bleeding, Hct may drop)

– Arterial blood gases: metabolic acidosis– Elevated serum lactate (serum lactate greater

than 4 mmol/L)




Diagnostic Criteria (cont.)

•Reviews laboratory studies for:– Reduced mixed venous oxygen saturation

(SvO2 less than 60%; ScvO2 less than 70%)




Learning Outcome 2




Hypovolemic Shock

•In hypovolemic shock, the heart rate is increased

•MAP, CVP/RA, and PAWP are decreased, reflecting a reduced preload

•A reduction in circulating volume may also lead to a reduction in SV and CO/CI

•An elevated SVR may be present, reflecting the vasoconstriction due to compensatory mechanisms




Learning Outcome 3




Collaborative Management Goals

•Early identification of hypovolemic shock is the key to successful outcome

•Goal of treatment is to expand intravascular volume

•Restore a normal circulating volume




Restoration of Volume

•Requires fluid challenges of an isotonic solution through large bore intravenous catheters

•Examples of isotonic crystalloid solutions include 0.9% normal saline and lactated Ringer’s solution




Restoration of Volume (cont.)

•These isotonic solutions are infused into the vascular space and stay there long enough to expand the intravascular space

•Fluid resuscitation starts with 1 to 2 liters of crystalloid over 10 to15 minutes. Standard, large (i.e., 14- to 16-gauge) peripheral IV catheters or central venous catheters are adequate for most fluid resuscitation




Restoration of Volume (cont.)

•The advantage of a central venous catheter is that it can be used to monitor CVP




Nursing Intervention

•Restore normovolemia and improve cardiac output

•Fluid challenge of isotonic solution

•Monitor CVP readings

•Monitor calcium level

•Assess of respiratory compromise




Prevention and Detection of Life-threatening Complications

•Renal insufficiency

•Cerebral ischemia

•Irreversible shock




Learning Outcome 4




Pathophysiology of Heart Failure

•As heart function fails and cardiac output decreases, compensatory mechanisms such as sympathetic nervous system and renin-angiotensin-aldosterone system, are activated

•The role of compensatory mechanisms is to maintain perfusion to the vital organs




Pathophysiology of Heart Failure (cont.)

•Long-term activation of these mechanisms can be deleterious, leading to:– Increased afterload– Pulmonary edema– Peripheral edema – Chamber dilation and/or hypertrophy—called

remodeling




Neurohormonal Mechanisms of Heart Failure

•Primary mechanisms are sympathetic nervous system

•Renin-angiotensin-aldosterone system

•Activation of sympathetic nervous system releases norepinephrine = increased vasoconstriction, heart rate, and contractility

•Activation of renin-angiotensin-aldosterone system stimulates aldosterone




Learning Outcome 5




Systolic vs. Diastolic HF

Systolic Diastolic

Impaired left ventricular Ventricle is normal size but

contractility hypertrophies

Reduced ejection Loss of left ventricular

fraction (normal 55–75%) diastolic relaxation

Decreased cardiac output Ejection fraction normal

Filling of ventricles impaired

PAWP is elevated




Learning Outcome 6




Clinical Manifestations of Heart Failure

•Manifestations occur depending on the location of the failure

•Left-sided heart failure results in respiratory manifestations

•Right-sided heart failure results in peripheral manifestations




Clinical Manifestations of Heart Failure (cont.)

Left-sided Right-Sided Manifestations ManifestationsDyspnea on exertion Peripheral edemaOrthopnea Abdominal pain and distentionParoxymal noctural Weight gaindyspneaCrackles on Ascitespulmonary auscultation Jugular vein distention




End Organ Hypoperfusion Is Manifested By:

Decreased exercise Fatigue

tolerance

Dizziness Syncope

Palpitations Hypotension

Tachycardia Cool extremities

Delayed capillary refill Decreased urinary output




Learning Outcome 7




Hemodynamic Findings

•Nurse monitors for trends indicating volume overload or decompensation

•Elevated filling pressures may be elevated in heart failure

•RA/CVP (right filling pressures) is elevated = peripheral edema




Hemodynamic Findings (cont.)

•PAWP (left filling pressures) is elevated = pulmonary edema

•Cardiac output normal

•Elevated systemic and pulmonary vascular resistance




Diagnostic/Laboratory Tests

•Laboratory Tests– Sodium– BUN and creatinine– B-type natriuretic peptide

•Diagnostic Tests– Chest x-ray– ECG– Noninvasive cardiac tests– Invasive cardiac tests




Learning Outcome 8




Contrasted Hemodynamic Findings of Heart Failure and Hypovolemia

Heart Failure Hypovolemia

RA/CVP is elevated RA/CVP is decreased

PAWP is elevated MAP is decreased

Cardiac output normal CO/CI is reduced

Elevated systemic and SV reduced

pulmonary vascular

resistance




Learning Outcome 9




Collaborative Management

•Nurse works with MD to manage symptoms

•Reduce the progression

•Prolong survival

•Pharmacological and nonpharmacologic measures




Nurse Management/Interventions

•Administer medications as ordered– Ace inhibitors– Beta blockers– Aldosterone antagonists

•Monitor for side effects of ace inhibitors– Dizziness– Hypotension– Cough– Hyperkalemia




Nurse Management/Interventions (cont.)

•Monitor for fluid volume excess– Administer diuretics– Monitor intake and output– Assess respiratory status

•Monitor for impaired gas exchange

•Monitor for decreased cardiac output– Vasodilators– Inotropes– Digoxin




Nurse Management/Interventions (cont.)

•Monitor for complications and interventions– Dysrhythmias– Pulmonary edema– Hypercarbia– Cardiogenic shock




Common Medications Used for Complications

•Venodilators– Morphine sulfate– Nitroglycerin

•Vasodilators– Nesiritide (Natrecor)

•Intravenous inotropics– Dobutamine– Milrinone




Learning Outcome 10




Acute Decompensated Heart Failure (Cardiogenic Shock)

•Prevention is linked to early detection and appropriate management

•Patient compliance with lifestyle modifications may decrease occurrence

•Appropriate nurse assessment is crucial




Nurse Assessment of Decompensated Heart Failure

•Dyspnea at rest•Tachycardia•Reduced oxygen saturation•Crackles on lung auscultation•Hypotension•Worsening cough•New dysrhythmias•Elevation of PAWP•Reduction in CO/CI




Learning Outcome 11




Collaborative Management of Acute Decompensated Heart Failure

•Oxygen therapy of 100% nonrebreathing mask

•BIPAP may be appropriate




Nursing Management

•Assess for complications from CPAP or BIPAP– Air leak around the mask– Facial skin breakdown– Gastric distention– Vomiting and aspiration– Claustrophobia




Pharmacological Interventions

•Venodilators (morphine and nitroglycerin)•Venodilators reduce preload and PAWP•Morphine sulfate reduces anxiety and

venodilate•Nurse must assess for side effects/adverse

reactions of morphine– Excessive decrease in respiratory rate– Excessive decrease in oxygen saturation– Hypotension– Decreased level of consciousness




Nitroglycerin

•Clients who do not respond to morphine may be treated with nitroglycerin

•Nitroglycerin Administration– Special tubing to prevent excessive

absorption of the drug– Assess blood pressure, heart rate, respiratory

rate, and oxygen saturation– Assess for side effects: hypotension,

tachycardia, headache




Other Pharmacological Interventions

•Nesiritide (Natrecor) given IV– Does not increase heart rate– Cannot replace diuretics– Closely monitor the blood pressure

•Intravenous inotropic therapy– Clients who remain in pulmonary edema– Dobutamine and milrinone (Primacor)

•Increase dose of diuretics (IV)




Signs of Cardiogenic Shock

•Cardiac index < 2.0 L/min

•Systolic blood pressure less than 90 mmHg

•PAWP above 19 mm Hg

•Intraaortic balloon pump may be used

Chapter 6 Care of the Patient Experiencing Shock or Heart Failure

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Transcript of Chapter 6 Care of the Patient Experiencing Shock or Heart Failure