Shock Flashcards
(36 cards)
What is shock?
Shock is a syndrome characterized by decreased tissue perfusion and impaired cellular metabolism.
Cardiogenic shock
systolic or diastolic dysfunction of the heart’s pumping action results in reduced CO, Stroke Volume, and BP.
What side of the heart does systolic dysfunction occurs?
It mainly occurs in the L. ventricle b/c pressure is greater on L. side of the heart.
What is the most common cause of systolic dysfunction?
ACUTE MI
What are the causes of Cardiogenic shock?
Dysrythmias, (Bradydysrthmias, Tachydystryhtmia) strucutral factors(Valvular stenosis), Systolic Dysfunction (MI), Diastolic Dysfunction( Cardiac tamponade)
What is the patho of Systolic Dysfunction?
1) Ineffective forward movement of blood
2) Decreased Stroke Volume
3) Decreased CO
4) Decreased Cellular Supply
5) Decreased tissue !!perfusion
6) Impaired cellular metabolism!!
What are EARLY presentations of Cardiogenic shock?
similar to Acute Demcompensated HF.
Tachycardia with hypotension, pulse pressure is narrowed.
Upon assessment: -Tachypneic
-crackles on auscultation , increased
-Pulmonary artery wedge pressure.
What are signs of peripheral hypo-perfusion?
-cyanosis
-pallor
-diaphoresis
-weak peripheral pulses
-cool and clammy skin
-Delayed cap refill
-
What is hypovolemic shock?
occurs from inadequate fluid in the intravascular space to support adequate perfusion.
What is the differences between hypovolemic shock and cardiogenic shock?
Cardiogenic shock has to do with filling and pumping dysfunction of the heart that decreases perfusion and hypovolemic shock is inadequate fluid in the intravascular space.
What are the two types of hypovolemic shock?
-Absolute: Loss of fluid from (hemorrhage, GI(vomiting and diarrhea, diabetes insipidus, and urination.
- Relative: Movement of fluid from intravascular space to the extravascular space (third spacing)
- Burns
What are the consequences of absolute and relative fluid loss?
1) Decreased venous return
2) Decreased SV
4) Decreased CO
5) Impaired cellular metabolism.
What are the compensatory mechanism for fluid loss?
1) Patient can compensate for (15%) of total blood volume (750mL)
2) 15-30% blood loss results in SNS response(Increased HR, CO, RR. )
- Crystalloid can be given
3) Greater than 30% loss is immediate replacement of blood products
4) Greater than 40% irreversible tissue destruction.
What is neurogenic shock?
happens within 30 minutes of a spinal cord injury. Loss of SNS vasoconstrictor tone that leads to massive vasodilation causing pooling of blood in blood vessels, hypo-perfusion, and impaired cellular metabolism.
What are the classical manifestations of neurogenic shock?
-Bradycardia(classical)
-Hypotension(classical)
Other Manifestations:
-Not regulate temperature
-1st skin: warm –> then cold
(poikilothermia)
What is spinal shock?
Absence of voluntary and reflex below the level of injury.
What is septic shock?
characterized by persistent hypotension, despite fluid resuscitation and inadequate tissue perfusion that results in tissue hypoxia.
What are the main organisms that causes sepsis?
Gram -negative and gram positive bacteria
What are the 3 pathophysiologic effects?
1) vasodilation
2) Maldistribution of of BF
3) myocardial depression
What clinical presentation is common in shock?
Respiratory failure is common.
-Hyperventilation: leads to respiratory alkalosis then respiratory acidosis
What is obstructive shock?
physical obstruction to blood flow with a decreased CO
What causes obstructive shock?
1) restricted diastolic filling of the right ventricle from compression.
2) abdominal compartment syndrome
3) pulmonary embolism
What is the initial stage of shock?
- occurs at cellular level.
- S/S usually not apparent
- Metabolism: aerobic to anaerobic –> LACTIC BUILDUP
- Liver metabolizes it, but not enough 02 because of decrease in tissue perfusion
What is the compensatory Stage?
- Classic sign is DROP in B/P
- SNS is activated due to drop and maintains BF
- BF to nonvital organs is diverted
