Shock What is Shock ? ? ? Shock is a failure of the ...
Transcript of Shock What is Shock ? ? ? Shock is a failure of the ...
What is Shock ? ? ?
Shock is a failure of the circulatory system to maintain adequate perfusion of vital organs.
cellular hypoxia
anaerobic cellular metabolism
accumulation of waste products in cells
cellular death
Types of Shock
• Distributive Shock– Neurogenic shock– Septic shock– Anaphylactic shock
• Hypovolemic Shock• Cardiogenic Shock
Distributive Shock
Distributive shock occurs as a result of inadequate vascular tone.
• neurogenic shock• septic shock• anaphylactic shock
Hypovolemic Shock
Hypovolemic shock occurs when there is a large reduction in the circulating blood volume.
• Actual hypovolemic shock - loss of blood or fluid
• Relative hypovolemic shock - internal fluid shifts from intravascular to interstitial space.
Cardiogenic Shock
Cardiogenic shock occurs when the heart is unable to function adequately resulting in insufficient blood flow to tissue and organs.
• myocardial infarction
• obstruction of blood flow
• congestive heart failure
Stages of Shock
• Initial Stage
• Compensatory Stage
• Progressive Stage
• Irreversible Stage
Stages of Shock
• Initial StageInitial Stage
• Compensatory Stage
• Progressive Stage
• Irreversible Stage
Initial Stage
• Initially, the body compensates with the onset of shock.
• No changes are noted clinically.
• Changes are beginning to occur on the cellular level.
Stages of Shock
• Initial Stage
• Compensatory StageCompensatory Stage
• Progressive Stage
• Irreversible Stage
Compensatory Stage
• Fluid shift from insterstital to intravascular space.
• Activation of SNS - activation of epinephrine and norepinephrine.
• Kidneys release renin into blood formation of angiotension & release of aldosterone, ADH
Decreased CO
SNS stimulation
Epinephrine & norepinephrine released
Vasoconstriction
Increased SVR
Renin secreted by kidney
Angiotension
Aldosterone
ADH
Increase blood volume
hydrostatic pressure
fluid pulled into capillary
Blood Pressure Maintained
• Initial Stage
• Compensatory StageCompensatory Stage
• Progressive StageProgressive Stage
• Irreversible Stage
Stages of Shock
Progressive Stage
• Vicious circle of compensation eventually leads to decompensation.
• Blood pressure starts to fall - SBP below 80 is considered danger signal.
• Tachycardia; tachypnea; decreased urine output; decreased body temperature; cold, pale clammy skin.
• Initial Stage
• Compensatory StageCompensatory Stage
• Progressive StageProgressive Stage
• Irreversible StageIrreversible Stage
Stages of Shock
Irreversible Stage
• Body attempts at compensation have failed - death is imminent.
• Pooling and sludging of blood; thrombosis of small vessels occurs.
• Tissue hypoxia and anoxia occur - lactic acid accumulation contributes to cell death.
Management of Shock
* Treat underlying cause.– Knowing the cause of the shock is necessary to
treat the shock.
Management of Shock
* Oxygenation– In all types of shock, supplemental oxygen is
administered to protect against hypoxemia.
Management of Shock
* Positioning– the recommended position for the patient in
shock is supine with legs elevated 45 degrees.
Management of Shock
* Replacing Fluid Volume– The primary goal of shock therapy is to
increase the circulating blood volume.• crystalloids
• colloids
– Fluid replacement should be based on central venous pressures or pulmonary artery pressures and cardiac output.
Management of Shock
– Vasoconstrictors• Dopamine
• Norepinephrine
– Vasodilators• Nitroprusside
• Nitroglycerin
– Sympathomimetics• Epinephrine
– Corticosteriods• Decadron
• Solumedrol
– Appropriate antidotes or antibiotics
* Pharmacologic Agents
Complications of Shock
• Metabolic Acidosis
• Acute Tubular Necrosis
• DIC
• ARDS
• SIRS & MOSF
SIRS & Multi-Organ System Failure
• May occur in patient who has survived a shock episode.
• Commonly associated with septic shock, especially gram negative septic shock
Systemic Inflammatory Response Syndrome
Causes damage to organs and tissues by:– damaging vascular endothelial cells– hypermetabolism– maldistribution of blood flow to organs– organ hypoperfusion
New Priorities in Septic Shock Care
• Multiple multi national research projects
• 4 new findings, care priorities1. Use of activated protein C (Xigris)- new IV
medication for septic shock• expensive but effective
2. Use of high dose steroids • test for reactiveness, then individualized dosing
3. Intensive insulin therapy• tight glucose control (<110)
4. Aggressive fluid therapy, monitoring
Shock: Recap
Types of Shock
• Distributive Shock– Neurogenic shock– Septic shock– Anaphylactic shock
• Hypovolemic Shock
• Cardiogenic Shock
Recap
Stages of Shock
• Initial Stage
• Compensatory Stage
• Progressive Stage
• Irreversible Stage
Recap…..
Treatment of Shock– O2,O2,O2, did I say oxygen?– Positioning– Fluids
• Colloids• Crystalloids
– Pharmacological agents
Cutting Edge Therapies
• Use of Xigris
• Use of steroids
• Intensive insulin therapy
• Aggressive fluid resuscitation/ monitoring