Shock, its pathogenesis and types along wth diagnosis and treatment

2. SHOCK

3. CONTENTS:
• Definition
• Pathogenesis
• Types
• Stages
• Diagnosis
• Treatment

4. DEFINITION:
• Medically, shock is defined as a condition where the
tissues in the body don't receive enough oxygen
and nutrients to allow the cells to function.
• Low Tissue perfusion occurs which may cause
ischemia if for longer period can cause tissue
necrosis, untreated, organ failure..

5. PATHOGENESIS:
• When oxygen supply decreases, instead of using aerobic pathway the tissues use
anaerobic pathway to produce energy. In anaerobic pathway, lactic acid is produced
as byproduct which leaks many toxic substances in blood stream causing vessels to
damage..
• Decreased oxygen supply can be due to;
• Amount of air inhaled decreased
• Injury to lungs making them unable to transfer oxygen to blood stream
• Heart may not be able to pump blood

6. PATHOGENESIS(CONTD)
• Blood volume
Venous Return
Cardiac Output
Blood Flow
Supply Of Oxygen
Anoxia
SHOCK

7. TYPES OF SHOCK:
• 4 Basic types of shock
• Hypovolemic Shock
• Cardiogenic Shock
• Obstructive Shock
• Distributive Shock; Anaphylactic shock
• Septic Shock
• Neurogenic Shock

8. HYPOVOLEMIC SHOCK:
• Most common type of shock
• Caused by insufficient circulating blood volume
• ETIOLOGY:
• hemorrhage (internal or external) (most common)
• diarrhea vomiting burns excess urine
loss due to diabetes insipidus

9. CARDIOGENIC SHOCK:
• Caused by the failure of the heart to pump effectively
• ETIOLOGY:
• due to damage to the heart muscle, most often from a large myocardial infarction
• Other causes of cardiogenic shock include dysrhythmias,
cardiomyopathy/myocarditis, congestive heart failure (CHF), myocardial contusion,
or valvular heart disease problems

10. OBSTRUCTIVE SHOCK:
• Obstructive shock is caused by some obstruction either surrounding the heart or the
blood vessels that prevents blood form being pumped forward
• Etiology:
• Cardiac Tamponade
• Pulmonary Embolism
• Tension Pneumothorax
• Air Embolism

11. DISTRIBUTIVE SHOCK:
• Is low blood pressure due to a dilation of blood vessels within the body
• caused by systemic infection (septic shock)
• a severe allergic reaction (anaphylaxis)
• or spinal cord injury (neurogenic shock).

12. SEPTIC SHOCK:
• It is caused by overwhelming systemic infection resulting in vasodilation leading to
hypotension
• ETIOLOGY:
• Gram +ive bacteria
• Gram –ive bacteria
• Fungi/ Virus
• Protozoa

13. ANAPHYLACTIC SHOCK:
• Anaphylactic shock is caused by a severe anaphylactic reaction to an allergen,
antigen, drug or foreign protein causing the release of histamine which causes
widespread vasodilation, leading to hypotension and increased capillary
permeability
• ETIOLOGY:
• Injections
• Anesthetics
• Stings etc

14. NEUROGENIC SHOCK:
• It Is Caused by the sudden loss of signals from the sympathetic nervous system that
maintain the normal muscle tone in blood vessel walls.
• The blood vessels relax and become dilated, resulting in pooling of the blood in the
venous system and an overall decrease in blood pressure.
• ETIOLOGY:
• Complication of injury to the brain or spinal cord.

15. STAGES OF SHOCK:
• 3 Stages of shock
• Compensated (non progressive)
• Decompensated( Progressive)
• Irreversible

16. COMPENSATED STAGE
• In This Stage, when low blood flow (perfusion) is first detected, a number of systems
are activated in order to maintain/restore perfusion.
• The result is that:
• heart beats faster
• the blood vessels throughout the body become slightly smaller in diameter
• the kidney works to retain fluid in the circulatory system.
• All this serves to maximize blood flow to the most important organs and systems in
the body.
• The patient in this stage of shock has very few symptoms, and aggressive treatment
may slow progression.

17. DECOMPENSATED STAGE:
• In this stage, these methods of compensation begin to fail. The systems of the body
are unable to improve perfusion any longer, and the patient's symptoms reflect that
fact. Oxygen deprivation in the brain causes the patient to become confused and
disoriented

18. IRREVERSIBLE STAGE:
• At this stage, the vital organs have failed and the shock can no longer be reversed.
Brain damage and cell death are occurring, and death will occur imminently.

19. DIAGNOSIS;:
• Diagnosis of shock is based on the patient's symptoms, as well as criteria including a
significant drop in blood pressure, extremely low urine output, and blood tests that
reveal overly acidic blood with a low circulating concentration of carbon dioxide.
Other tests are performed, as appropriate, to try to determine the underlying
condition responsible for the patient's state of shock.

20. TREATMENT:
• Treatment includes:
• keeping the patient warm, with legs raised and head down to improve blood flow
to the brain
• Giving fluid replacement or blood transfusions, as necessary
• Giving the patient extra oxygen to breathe and medications to improve the heart's
functioning
• AND treating the underlying condition which led to shock.

21. REFERNCES:
• https://www.ems1.com/ems-products/medical-equipment/airway-
management/tips/a-basic-overview-of-shock-ruVOZ8HOYPTDeYCm/
• https://www.emedicinehealth.com/shock/article_em.htm#shock_self-care_at_home
• https://en.wikipedia.org/wiki/Shock_(circulatory)