This topic covers the etiology, types, pathogenesis and management of Shock. It is very important for MBBS Students both theoretical & clinical aspect. Also they should know the hemodynamics across the types of shock in treating the patients....
2. Learning Objectives
•Definition
• Types of Shock & Aetiology
•Pathophysiology
• Clinical Features
•Stages of shock
• Effects of Shock
• Consequences of Shock
• Management of Shock
3. • Shock is a systemic state of low tissue
perfusion that is inadequate for
normal cellular respiration.
• It is either reduced oxygen delivery
(or) poor oxygen utilization (or)
increased oxygen consumption with
circulatory failure (collapse) and poor
perfusion.
• With insufficient delivery of oxygen
and glucose, cells switch from aerobic
to anaerobic metabolism.
• If perfusion is not restored in a timely
fashion, cell death ensues.
Definition
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17. Type of Shock CO / CI
[Pump Function]
PCWP
[Preload]
SVR
[Afterload]
Venous O2
Saturation
[Perfusion]
Cardiogenic
Hypovolemic
Obstructive
Septic
Anaphylactic
Neurogenic
Hypo-adrenal N /
S & A C & O C H O S A N
Hemodynamics in Shock
25. • During the period of systemic hypoperfusion,
cellular & humoral elements activated by
the hypoxia (complement, neutrophils,
microvascular thrombi), overwhelm the local
anti-inflammatory response, where they
cause injury to distant organs resulting in
SIRS.
• It is final common pathway in shock due to
any cause (trauma, sepsis, endotoxemia,
burns).
• It is a part of severely decompensated
reversible shock which eventually leads to
MODS (Multiorgan dysfunction syndrome), a
state of irreversible shock wherein patient is
anuric, drowsy, cold and terminally ill. SIRS
carries poor prognosis.
Consequences - SIRS
26. • The result of prolonged systemic
hypoperfusion, cellular & organ damage
progresses to end organ damage and multiple
organ failure.
• Multiple organ failure is defined as two or
more failed organ systems.
• It is progressively becoming irreversible injury
of all tissues like kidney, lungs, liver, GIT. Lungs
and liver are commonly involved (70% ). Next
organs to be involved are kidney and GIT.
• Management of MODS is critical care in ICU
with ventilator support, hemodialysis,
transfusions, antibiotics, proper nutrition in the
form of TPN or enteral. MODS stage has got
high mortality [60%].
Consequences – MOF / MODS
33. • Vasopressor (or) inotropic therapy is not
indicated as first line therapy in
hypovolemia.
• Vasopressor agents (phenylephrine,
noradrenaline) are indicated in distributive
shock states (sepsis, neurogenic shock)
where there is peripheral vasodilatation & a
low systemic vascular resistance. Resistant to
catecholamines vasopressin may be used.
• In cardiogenic shock, or where myocardial
depression has complicated a shock state
(e.g., severe septic shock with low cardiac
output), inotropic therapy may be required
to increase cardiac output and therefore
oxygen delivery. Dobutamine is the agent of
choice.
Vasopressor & Inotropic Support
34. • Definition & Types of Shock.
• Aetiology of Shock.
• Pathophysiology of Shock.
• Clinical features of various types of Shock.
• Different Stages of Shock.
• Effects of Shock on various organs in the body.
• Complications of Shock – SIRS & MODS.
• Monitoring of a patient in Shock | Treatment aspects of Shock.
To Summarize
36. • Define shock.
• Illustrate with flow-chart the pathophysiology of shock.
• Classify shock and list their aetiology.
• Mention the typical C/F of shock.
• How do you monitor a shock patient?
• Enumerate the complications of shock.
• Explain the stages of shock.
• Write about dynamic fluid response aspects of shock.
Question Time
37. One of the following is not true about
distributive shock –
◼ a) Decreased venous return.
◼ b) Decreased cardiac output.
◼ c) Decreased vascular resistance.
◼ d) High mixed venous saturation.
◼
38. First line of therapy in shock in the patients of
trauma is –
◼ a) Crystalloids.
◼ b) Colloids.
◼ c) Inotropes.
◼ d) Blood transfusion.
◼
39. A patient with spine, chest and abdominal injury in
road traffic accident developed hypotension and
bradycardia. The most likely reason is –
◼ a) Hypovolemic shock.
◼ b) Hypovolemic + neurogenic shock.
◼ c) Hypovolemic + septicemic shock.
◼ d) Neurogenic shock.
◼
40. There are several mechanisms of organ hypoperfusion
and shock. Which one of the following types of shock is
due to vasodilation? –
◼ a) Obstructive shock.
◼ b) Hypovolemic shock.
◼ c) Cardiogenic shock.
◼ d) Distributive shock.
◼
41. One of the following is not used as minimum
monitoring measures for patients in shock –
◼ a) ECG.
◼ b) Serum lactate.
◼ c) Blood pressure.
◼ d) Pulse oximetry.
◼
42. The two common organs involved in the
multiple organ failure following shock is –
◼ a) GIT & Lungs.
◼ b) Kidney & GIT.
◼ c) Lungs & Liver.
◼ d) Liver & Kidney.
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