Multisystem Alterations Shock Flashcards
what is circulatory shock? etiology? patho? stages?
-Inability of circulation to adequately perfuse 02 body tissues and vital organs.
-Common factor in all shock is hypo-perfusion & impaired cellular 02 use
-Managed by treating underlying etiology & improving CO & perfusion.
Etiology
-Decreased CO
-Changes in distribution of blood flow
-Reduced blood 02 content
-Increased metabolic demand
Pathogenesis
Imbalance between 02 supply & demand at cellular level; may progress to organ failure & death
Clinical stages of shock
Compensatory responses attempt to restore tissue perfusion & oxygenation.
-Compensated stage
-Progressive stage
-Refractory stage
what is compensatory phase? CM?
-Decrease in CO that results from shock state.
-Compensatory mechanisms able to maintain adequate but decreased perfusion despite reduction in CO.
-Cardiac contractility, rate, & peripheral vasoconstriction increase.
-Decreased renal perfusion initiates the RAAS.
Clinical Manifestations:
-Tachycardia
-Fast & deep respirations
-Cool, clammy skin
-Altered mentation
-Dilated pupils
-Decreased urinary output & increased urine specific gravity
-Narrow pulse pressure with or without HTN
what is progressive phase? CM?
-Compensatory mechanism can no longer maintain perfusion or normal BP
-Progressive tissue hypoxia from vasoconstriction.
-Body shifts from aerobic to anaerobic respiration resulting in metabolic acidosis.
-Cells die due to hypoxia, oncotic pressure increased, pushing fluid into interstitial spaces, causing edema and decreasing circulating volume
Clinical Manifestations:
-Hypotension
-Narrow pulse pressure tachycardia
-Acute renal failure (oliguria, increased BUN & Creatinine)
-Decreased level of consciousness (LOC)
-Increased respiratory rate
-Metabolic acidosis
what is refractory phase?
-Is Irreversible; refractory to tx & results in death.
-Microcirculation has been compromised beyond repair resulting in widespread cellular death.
what is cardiogenic shock? etiology? patho? CM?
Inadequate cardiac output
Etiologies
-MI most common. Usually d/t severe ventricular dysfunction
-Cardiomyopathy (ineffective heart muscles)
-Valvular Heart Disease
-Congenital Heart Defects
-Coronary Artery Disease
-Cardiac Dysrhythmias
-Papillary Muscle Rupture
Pathogenesis
-Ineffective pumping leads to reduced CO & tissue perfusion
-Adequate volume but inadequate perfusion
-SNS activation causes increase 02 consumption & greater stress on heart.
Clinical manifestations:
-Restlessness
-Agitation
-Hypotension
-Tachycardia with weak, thready pulse
-Cardiac arrhythmias
-Decreased pulse pressure
-Crackles
-Tachypnea
-JVD
-Cool, moist skin
-Circumoral cyanosis
-Dusky nail beds
-S3 heart sounds
-Pulmonary edema
what is hypovolemic shock? etiology? patho? CM?
Loss of volume
Etiology:
-Acute hemorrhage
-Dehydration d/t vomiting & diarrhea
-Overuse of diuretics
-Burns
-Pancreatitis
Pathogenesis:
-Decreased circulating blood volume and CO & tissue perfusion
-Leads to SNS activation = vasoconstriction, elevated HR & contractility
-Severity r/t amount of fluid loss, occurs when volume reduced by 15% to 20%.
Clinical Manifestations:
-Thirst
-Tachycardia
-Pallor
-Restless, anxious
-Episodes of confusion
-Hypotension
-Cardiac dysrhythmias
-Cyanosis
-Oliguria
Tx: Fluid replacement & control of source of fluid loss.
what is obstructive shock? etiology? patho? CM?
Circulatory blockage
-Mechanical obstruction prevents heart from pumping
-Impaired ventricular filling leads to reduced CO & S/S of circulatory shock.
Etiologies:
-Pulmonary embolism
-Cardiac tamponade
-Tension Pneumothorax
-Dissecting aortic aneurysm
Pathogenesis:
-Ventricles unable to fill or empty.
-Preload and CO is decreased.
Clinical Manifestations:
-Somnolence
-Hypotension
-Tachycardia with dyspnea
-JVD
-Pallor
-Pericardial friction rub
-Chest pain
-Oliguria
TX: Rapid management of obstruction is required to prevent cardiovascular collapse.
what is anaphylactic shock? etiology? patho? CM? tx?
-Overwhelming immune response to presence of allergen or antigen.
Etiologies:
-Abx & contrast media
-Food
-Bites, insect, snake
Pathogenesis:
-Antibody-antigen rxn releases large amts of histamines into blood, causing marked vasodilation & capillary permeability
-Fluid shift into interstitial spaces causes edema.
-Vasodilation causes pooling & drop in BP
-Laryngeal edema may occur.
Clinical Manifestations:
-Restlessness
-Severe itching & difficulty swallowing
-Hypotension
-Tachycardia
-Tachypnea with wheezing
-Urticaria
-Edema
-Dysrhythmias
-Abd cramping, vomiting
TX: Maintenance of airway patency, antihistamines, vasopressors & fluids.
what is neurogenic shock? etiology? patho? CM? tx?
Etiologies:
-Spinal cord trauma
-Drug overdose
-Brain injury
Pathogenesis:
-Increased parasympathetic stimulation causes peripheral vasodilatation, decreasing BP & causing hypotension.
-Peripheral pooling of blood decreases venous return to heart.
-Preload & CO decrease.
Clinical Manifestations:
-LOC varies
-Hypotension
-Bradycardia
-Hypothermia
-Oliguria
Treatment: Vasopressors & fluids
what is septic shock? etiology? patho? CM? tx?
Overwhelming systemic infection with mortality rate of 40-80%
Etiology: Bacteria & fungal infections
Pathogenesis:
-Endotoxins cause severe systemic inflammatory response
-Clotting cascade activated.
-Inflammation leads to peripheral vasodilatation with hypotension.
-Maldistribution of blood flow (02) with cell hypoxia
-High CO, but insufficient blood volume.
Clinical Manifestations:
-Agitation
-Nausea and vomiting
-Normotensive
-Tachycardia, tachypnea
-Flushed skin
-Hyperthermia
-Shivering
Tx: Improve distribution of blood flow & manage infection with abx
what is acute respiratory disease?
-Lethal form of respiratory failure most commonly associated with septic shock.
-Lungs become stiff & noncompliant with decreased elasticity of alveoli.
-Causes decreased ventilation, hypoxemia & pulmonary edema.
-Results in capillary permeability in lungs with fluid accumulation.
-Cell injury & death.
what is disseminated intravascular coagulation?
-Abnormal clot formation in microvascular vessels due to immune activation of clotting cascade.
-Microcirculation obstructions lead to ischemic tissue damage
-Extensive clotting depletes platelets & clotting factors; allowing for severe bleeding.
-Most commonly associated with septic shock
what is acute renal failure?
-Kidneys endure long periods of hypoperfusion
-Vasoconstriction causes decreased glomerular blood flow and decreased GFR
-Acute tubular necrosis (ATN) develops
-Decreased urinary excretion of waste products (creatinine and urea)
-Hypoxic cellular damage & necrosis of renal tubules
what is multiple organ dysfunction syndrome?
-Organ dysfunction in 2 or more systems initiated by immune mechanisms that are overactive & destructive.
-Ongoing inflammation leads to tissue destruction & organ dysfunction.
-Sepsis & septic shock are most common causes.
