Shock Flashcards
Shock is BROADLY DEFINED AS
AN IMBALANCE BETWEEN OXYGEN DELIVERY TO TISSUES AND OXYGEN CONSUMPTION BY THE TISSUES.
Shock is Most commonly classified by hemodynamic effects (circulatory) aka…? (4)
Hypovolemic
Cardiogenic
Distributive
Obstructive
Note that Multiple types can co-exist.
Several clinical stages of shock are recognized - based on the extent of physiological compensation.
Shock is sometimes also classified based on non-circulatory causes or effects aka..?
hypoxic and metabolic
Note that Multiple types can co-exist.
Several clinical stages of shock are recognized - based on the extent of physiological compensation.
Describe obstructive shock.
Obstructive shock is a type of shock that occurs when there is a physical obstruction in the circulatory system that impedes blood flow.
This obstruction can prevent the heart from effectively pumping blood, leading to inadequate perfusion of tissues and organs.
Common causes may be pericardial effusion, pulmonary embolism, cardiac tamponade or tension pneumothorax.
Describe distributive shock.
Distributive shock is a type of shock characterized by widespread vasodilation, which results in a significant drop in systemic vascular resistance and inadequate tissue perfusion despite an adequate or increased cardiac output.
In this condition, blood vessels are dilated excessively, leading to a relative hypovolemia and poor distribution of blood flow.
Common causes may be septic shock with release of inflammatory mediators, anaphylactic, neurogenic and endocrinologic shocks.
Describe cardiogenic shock.
Cardiogenic shock occurs when the heart is unable to pump sufficient blood to meet the body’s needs, despite adequate blood volume. This results in decreased cardiac output and poor tissue perfusion.
Common causes include myocardial infarction, end-stage cardiomyopathy, valve dysfunction, arrhythmias etc.
Describe hypovolemic shock.
Hypovolemic shock occurs when there is a significant loss of blood or fluids from the body, leading to a decreased blood volume.
This reduction in blood volume impairs the heart’s ability to pump effectively and reduces tissue perfusion, which can result in organ failure.
Common causes include internal or external fluid loss leading to organ failure.
List all the types of shock, both circulatory and non. (6)
hypovolemic (most common)
cardiogenic
obstructive
distributive
hypoxic
metabolic
causes of hypovolemic shock can be divided into..?
hemorrhagic and non-hemorrhagic
both of the above are further divided into internal vs external
Stages of shock can be broadly defined as
mild (compensatory)
moderate
severe (decompensatory)
Causes of external non-hemorrhagic hypovolemic shock? (6)
urine, vomitus, diarrhea, excessive salivation, burns, metabolic such as diabetes insipidus or DKA (excessive osmotic diuresis)
Decreased fluid intake could be due to..?
unable to drink
uninterested in drinking
Distributive shock is caused by..?
Give examples.
Maldistribution of blood flow
Vasodilatation
for example
- SIRS- systemic inflammatory response syndrome
- Infectious and non-infectious causes
Trauma
Pancreatitis
Burns …… - Sepsis
- Anaphylactic shock
Typical clinical signs of distributive shock. (4)
tachycardia in dogs but bradycardia in cats
mm hyperemic in dogs, mm pale in cats
CRT <1s in dogs, variable in cats
temp high in dogs, low in cats
Criteria for diagnosis of SIRS.
Systemic inflammatory response syndrome
Required: Presence of inflammatory foci + 2 or more criteria for dogs, and 3 or more in cats.
HR elevated in dogs, HR elevated OR decreased in cats
RR increased in both