Otkazivanje Otkazivanje srca i srca i

cirkulatorni cirkulatorni šokšok

Otkazivanje srcaOtkazivanje srca Function of the heart Function of the heart

Move deoxygenated blood from the Move deoxygenated blood from the venous system through the right heart venous system through the right heart into the pulmonary circulationinto the pulmonary circulation

Move the oxygenated blood from the Move the oxygenated blood from the pulmonary circulation through the left pulmonary circulation through the left heart into the arterial systemheart into the arterial system Right and left heart must maintain an equal Right and left heart must maintain an equal

output to function properlyoutput to function properly

Right Heart FailureRight Heart Failure Represents failure of the right heart Represents failure of the right heart

to pump blood forward into the to pump blood forward into the pulmonary circulationpulmonary circulation Blood backs up in the systemic Blood backs up in the systemic

circulationcirculation Causes peripheral edema and congestion of Causes peripheral edema and congestion of

the abdominal organsthe abdominal organs

Left Heart FailureLeft Heart Failure Represents failure of the left heart to Represents failure of the left heart to

move blood from pulmonary move blood from pulmonary circulation into system circulationcirculation into system circulation Blood backs up in the pulmonary Blood backs up in the pulmonary

circulationcirculation

Causes of Heart FailureCauses of Heart Failure Myocardial diseaseMyocardial disease

CardiomyopathiesCardiomyopathies MyocarditisMyocarditis Coronary insufficiencyCoronary insufficiency Myocardial infarctionMyocardial infarction

Causes of Heart Failure Causes of Heart Failure (cont.)(cont.)

Valvular heart diseaseValvular heart disease Stenotic valvular diseaseStenotic valvular disease Regurgitant valvular diseaseRegurgitant valvular disease

Congenital heart defectsCongenital heart defects Constrictive pericarditisConstrictive pericarditis

Cardiac OutputCardiac Output Cardiac output:Cardiac output: the amount of blood the amount of blood

the heart pumps each minutethe heart pumps each minute Cardiac output = heart rate x stroke volumeCardiac output = heart rate x stroke volume

Heart rate:Heart rate: how often the heart beats how often the heart beats each minuteeach minute Regulated by a balance between the Regulated by a balance between the

activity of the sympathetic sympathetic activity of the sympathetic sympathetic nervous system (increases heart rate), and nervous system (increases heart rate), and the parasympathetic nervous system (slows the parasympathetic nervous system (slows heart rate)heart rate)

Cardiac Output (cont.)Cardiac Output (cont.) Stroke volume:Stroke volume: how much blood how much blood

the heart pumps with each beatthe heart pumps with each beat A function of preload, afterload, and A function of preload, afterload, and

cardiac contractilitycardiac contractility

Maintenance of Cardiac Maintenance of Cardiac Reserve in Heat FailureReserve in Heat Failure

Compensatory or adaptive mechanisms Compensatory or adaptive mechanisms Frank-Starling mechanismFrank-Starling mechanism Activation of neurohumoral influences such Activation of neurohumoral influences such

as the sympathetic nervous systemas the sympathetic nervous system The renin-angiotensin-aldosterone The renin-angiotensin-aldosterone

mechanismmechanism Natriuretic peptidesNatriuretic peptides Locally-produced vasoactive substancesLocally-produced vasoactive substances Myocardial hypertrophy and remodelingMyocardial hypertrophy and remodeling

Causes of Heart FailureCauses of Heart Failure Acute myocardial infarctionAcute myocardial infarction HypertensionHypertension Degenerative conditions of the heart Degenerative conditions of the heart

muscle known collectively as muscle known collectively as cardiomyopathiescardiomyopathies

Excessive work demands Excessive work demands (hypermetabolic states)(hypermetabolic states)

Volume overload (renal failure)Volume overload (renal failure)

Descriptions of Heart Descriptions of Heart FailureFailure

High-output or low-output failureHigh-output or low-output failure Systolic or diastolic failureSystolic or diastolic failure Right-sided or left-sided failureRight-sided or left-sided failure

Causes of Right-Sided Causes of Right-Sided Heart FailureHeart Failure

Conditions that restrict blood flow into Conditions that restrict blood flow into the lungsthe lungs

Stenosis or regurgitation of the tricuspid Stenosis or regurgitation of the tricuspid or pulmonic valvesor pulmonic valves

Right ventricular infarctionRight ventricular infarction CardiomyopathyCardiomyopathy Persistent left-sided failurePersistent left-sided failure Acute or chronic pulmonary disease (Acute or chronic pulmonary disease (cor cor

pulmonale)pulmonale)

Causes of Left-Sided Causes of Left-Sided Heart FailureHeart Failure

Acute myocardial infarction Acute myocardial infarction CardiomyopathyCardiomyopathy

Manifestations of Heart Manifestations of Heart FailureFailure

Physiologic effects of the impaired Physiologic effects of the impaired pumping ability of the heartpumping ability of the heart

Decreased renal blood flowDecreased renal blood flow Activation of the sympathetic Activation of the sympathetic

compensatory mechanismscompensatory mechanisms

Signs and Symptoms of Signs and Symptoms of Heart FailureHeart Failure

Fluid retention and edemaFluid retention and edema Shortness of breathShortness of breath Fatigue and limited exercise toleranceFatigue and limited exercise tolerance CyanosisCyanosis Cachexia and malnutritionCachexia and malnutrition Distention of the jugular veins in Distention of the jugular veins in

right-sided failure right-sided failure Diaphoresis and tachycardiaDiaphoresis and tachycardia

Functional Classification Functional Classification of Patients with Heart of Patients with Heart

Disease (NY Heart Disease (NY Heart Association)Association) Class I:Class I: patients with cardiac disease but patients with cardiac disease but

without resulting limitations in physical activitywithout resulting limitations in physical activity Class II:Class II: patients with heart disease resulting patients with heart disease resulting

in slight limitations of physical activityin slight limitations of physical activity Class III:Class III: patients with cardiac disease patients with cardiac disease

resulting in marked limitation of physical resulting in marked limitation of physical activityactivity

Class IV:Class IV: patients with cardiac disease patients with cardiac disease resulting in inability to carry out any physical resulting in inability to carry out any physical activity without discomfort activity without discomfort

Goals of Treatment for Goals of Treatment for Chronic Heart FailureChronic Heart Failure

Relieving the symptoms and Relieving the symptoms and improving the quality of lifeimproving the quality of life

Long-term goal:Long-term goal: Slowing, halting, or reversing the Slowing, halting, or reversing the

cardiac dysfunctioncardiac dysfunction

Treatment Measures for Treatment Measures for Chronic Heart FailureChronic Heart Failure

Correction of reversible causes Correction of reversible causes Surgical repair of a ventricular defect or an Surgical repair of a ventricular defect or an

improperly functioning valveimproperly functioning valve Pharmacologic and non-pharmacologic control Pharmacologic and non-pharmacologic control

of afterload stresses of afterload stresses Modification of activities and lifestyle consistent Modification of activities and lifestyle consistent

with the functional limitations of a reduced with the functional limitations of a reduced cardiac reservecardiac reserve

Use of medications to improve cardiac function Use of medications to improve cardiac function and limit excessive compensatory mechanismsand limit excessive compensatory mechanisms

Acute Pulmonary EdemaAcute Pulmonary Edema Capillary fluid moves into the alveoli, Capillary fluid moves into the alveoli,

causes lung stiffness, makes lung causes lung stiffness, makes lung expansion more difficult, and impairs the expansion more difficult, and impairs the gas exchange function of the lung gas exchange function of the lung

With the decreased ability of the lungs With the decreased ability of the lungs to oxygenate the blood, the hemoglobin to oxygenate the blood, the hemoglobin leaves the pulmonary circulation without leaves the pulmonary circulation without being fully oxygenated being fully oxygenated Results in shortness of breath and cyanosisResults in shortness of breath and cyanosis

Causes of Cardiogenic Causes of Cardiogenic ShockShock

Damage to the heart from myocardial Damage to the heart from myocardial infarctioninfarction

Ineffective pumping caused by cardiac Ineffective pumping caused by cardiac arrhythmiasarrhythmias

Ventricular septal defectVentricular septal defect Ventricular aneurysmVentricular aneurysm Acute disruption of valvular functionAcute disruption of valvular function Problems associated with open heart Problems associated with open heart

surgerysurgery

Classification of Classification of Circulatory ShockCirculatory Shock

HypovolemicHypovolemic Loss of whole bloodLoss of whole blood Loss of plasmaLoss of plasma Loss of extracellular fluidLoss of extracellular fluid

ObstructiveObstructive Inability of heart to fill properly Inability of heart to fill properly Obstruction to outflow from the heartObstruction to outflow from the heart

Classification of Classification of Circulatory Shock (cont.)Circulatory Shock (cont.)

DistributiveDistributive Loss of sympathetic vasomotor toneLoss of sympathetic vasomotor tone Presence of vasodilating substance in Presence of vasodilating substance in

the bloodthe blood Presence of inflammatory mediatorsPresence of inflammatory mediators

Causes of Hypovolemic Causes of Hypovolemic ShockShock

Diminished blood volume with inadequate Diminished blood volume with inadequate filling of the vascular compartmentfilling of the vascular compartment

Acute loss of 15% to 20% of the Acute loss of 15% to 20% of the circulating blood volumecirculating blood volume External loss of whole blood (External loss of whole blood (e.g.,e.g.,

hemorrhage), plasma (hemorrhage), plasma (e.g.,e.g., severe burns), or severe burns), or extracellular fluid (extracellular fluid (e.g.,e.g., gastrointestinal fluids gastrointestinal fluids lost in vomiting or diarrhea)lost in vomiting or diarrhea)

Internal hemorrhage or from third-space Internal hemorrhage or from third-space losseslosses

Stages of Hypovolemic Stages of Hypovolemic ShockShock

Initial stage:Initial stage: the circulatory blood volume is the circulatory blood volume is decreased, but not enough to cause serious decreased, but not enough to cause serious effectseffects

Second stage:Second stage: Compensatory mechanisms are Compensatory mechanisms are able to maintain blood pressure and tissue able to maintain blood pressure and tissue perfusion at a level sufficient to prevent cell perfusion at a level sufficient to prevent cell damagedamage

Third stage:Third stage: Blood pressure begins to fall, blood Blood pressure begins to fall, blood flow to the heart and brain is impaired, capillary flow to the heart and brain is impaired, capillary permeability is increased, fluid begins to leave the permeability is increased, fluid begins to leave the capillaries, blood flow becomes sluggish, and the capillaries, blood flow becomes sluggish, and the cells and their enzyme systems are damagedcells and their enzyme systems are damaged

Stages of Hypovolemic Stages of Hypovolemic Shock (cont.)Shock (cont.)

Fourth and final stage:Fourth and final stage: irreversible irreversible shock, even though the blood volume shock, even though the blood volume may be restored and vital signs may be restored and vital signs stabilized, death ensues eventuallystabilized, death ensues eventually

Types of ShockTypes of Shock Obstructive shockObstructive shock Distributive shockDistributive shock

Neurogenic shockNeurogenic shock Anaphylactic shockAnaphylactic shock

Sepsis and septic shockSepsis and septic shock

Complications of ShockComplications of Shock Acute respiratory distress syndromeAcute respiratory distress syndrome Acute renal failureAcute renal failure Gastrointestinal complicationsGastrointestinal complications Disseminated Intravascular Disseminated Intravascular

CoagulationCoagulation Multiple organ dysfunction syndromeMultiple organ dysfunction syndrome

Signs and Symptoms of Signs and Symptoms of Heart Failure in Infants Heart Failure in Infants

and Childrenand Children FatigueFatigue Effort intoleranceEffort intolerance CoughCough AnorexiaAnorexia Abdominal painAbdominal pain