2. Definition
Shock is the clinical syndrome
Inadequate tissue perfusion
The hypoperfusion-induced imbalance
between the delivery & requirements for
oxygen
Substrate leads to cellular dysfunction
3. Types of Shock
SHOCK
Low stroke
volume
Hypovolaemic
Haemorrhage
Burn
Salt & water loss
Cardiogenic
MI
acute mitral
regurgitation
Obstructive
PE
Cardiac Tamponade
Tension
pneumothorax
Vasodilatation/
Distributive
Sepsis/SIRS
infection
Anaphylactic
Injection-penicillin
Bee sting
Anesthetics
selfish
Neurogenic Trauma to spinal cord
Spinal anesthesia
6. Hypovolaemic shock
Due to
a) Haemorrhage
-External from wounds, open fractures
-Internal from injury to spleen, liver,
mesentery or pelvis
b) Severe burn which result in loss of plasma
C) intestinal obstruction
c) Diarrhoea & vomiting of any cause
7. Hypovolaemic shock- Pathophysiology
Due to sudden loss blood volume or fluid from the vascular space.
Loss of blood
Filling of rt. Heart
Filling of pulmonary
vasculature
Filling of left
atrium & ventricle
Stroke
volume
Arterial
BP
SHOCK
9. Hypovolaemic shock- Management
ABC (AIRWAY is always first)
Control hemorrhage (splint the limb)
Obtain IV access with wide bore cannula
Resuscitate with fluids and blood
- Isotonic saline/ ringer’s lactate solution
- Blood transfusion if Hb <10g/dl
**Supplemental oxygen should always be
provided
10. Management goals AFTER securing the ABCs..
• STOP THE BLEEDING
• RESTORE VOLUME
• CORRECT ANY ELECTROLYTE/ACID-BASE
DISTURBANCES
Monitoring
Urine output
Vital signs
Skin perfusion
SP02 - Pulse Oximetry
12. Cardiogenic shock /Acute circulatory Failure
• Is a state of end-organ hypoperfusion due to
cardiac failure.
• Cardiogenic shock
-systemic hypoperfusion due to severe
depression of the cardiac index (<2.2 [L/min]/m2)
- sustained systolic arterial hypotension (<90
mmHg) despite an elevated filling pressure
(pulmonary capillary wedge pressure [PCWP]
>18 mmHg)
13. Causes of Cardiogenic shock
Systolic dysfunction
- CAD : Acute MI or ischemia (most common )
- Other conditions :
severe myocarditis
end stage cardiomyopathy
Prolonged cardiopulmonary bypass
Diastolic dysfunction
- CAD
- ventricular hypertrophy
14. Valvular or structural abnormality
(acute valve failure)
Aortic Regurgitation
-Aortic dissection
-Infective endocarditis
Mitral regurgitation
-Papillary muscle rupture due to acute MI
-Infective endocarditis
Prosthetic valve failure
-Mechanical valves: fracture , jamming, thrombosis
-Biological valves: degeneration with cusp tear
15. Arrhythmia
- VT/VF, bradycardia can cause shock
- sinus tachycardia can aggravate shock
Others
Restrictive cardiomyopathy
HOCM with Severe outflow obstruction
Prolong hypovolemia or septic shock
β-Blocker/CCB overdose
17. Risk factors for Cardiogenic Shock
Older Age
Prior MI
Diabetes Mellitus
HTN
Anterior MI
Extensive coronary artery stenosis
History of HF
STEMI New LBBB
18. Diagnosis
• Proper history & clinical examination
• ECG
• Chest X-ray
• Echocardiogram
• Blood specimen for laboratory investigation
** Supportive therapy must be initiated
simultaneously with diagnostic evaluation
19. Clinical findings
SIGN SYMPTOMS
Pulse weak , rapid (90-110BPM) / Severe
bradycardia due to HB
Systolic BP (<90mmHg)
Narrow pulse pressure (<30 mmHg)
Tachypnea
JVP distention
Soft s1 & an s3 gallop may found
Systolic murmurs- Severe MR, VSR
Crackles – LV failure
Oliguria
Chest pain
Vomiting
Palpitation
Dyspnea
Appear pale
Altered mental state
20.
21. A. General Measures
• In addition to immediate treatment of acute MI initial
therapy aimed
• Maintaining systemic BP by Vasopressors
• Ensure LV filling pressure by adjusting volume status
• Correct hypoxemia & acidosis
• May need ventilatory support
• Negative ionotropics must stopped
22. B. Pharmacological support
• VASOPRESSORS
Norepinephrine
-Potent vasoconstrictor & Inotropic stimulant
-May cause arrhythmia
-Can be used as initial vasopressor
therapy
-DOSE: 2-4µg/min to max. 15µg/min
Dopamine -Dose depended hemodynamic effect
-Better than Norepinephrine
-DOSE: 2-5µg/kg/min to max. 20-
50µg/kg/min
Dobutamine -Synthetic sympathomimetic amine
-Positive inotropic action
-DOSE: 10µg/kg/min
23. Inotropes and Vasopressors
(ACC/AHA Guidelines)
• SBP <70 mmHg
Norepinephrine (2-4µg/min to max. 15µg/min)
Switch to Dopamine (2-4µg/min to max. 15µg/min) once SBP ≥80
• SBP 70-100 mmHg
Dopamine (2-4µg/min to max. 15µg/min)
Add Dobutamine (2-20 g/kg/min) once SBP ≥90
24. C. Mechanical support
IABP
- Improve coronary & peripheral perfussion
- Initiate as quick as possible
- Higher rates of survival in high use centers
Newer devices
- LV, RV or BiV assist. Devices
- Impella, tendem heart, Extarcorporeal life
support (ECLS)
- Trials have shown hemodynamic
improvement but no survival benefit found
26. E. Treatment according to cause
Shock due to
RV infract
-3% of cardiogenic shock due to RV infract
& inf. Ischemia
-Fluid resuscitation
-Dopamine / Dobutamine
-Early reestablishment of infract artery flow
27. MR -Severe MR due to rupture papillary muscle
-Diagnosis: Echo-Doppler
-Rapid stabilization with IABP
-Dopamine / Dobutamine
VSR -Diagnosis: Echo-Doppler(Blood shunting Lt. to
Rt. & open in interventricular septum)
-Rapid stabilization with IABP
-Dopamine / Dobutamine
28. AHA Guideline
Class I
1. Early revascularization (PCI/CABG)
2. Fibrinolysis in candidates unsuitable for ERV with
no contraindications
Class II a
1. Use of IABP can be useful in pt. with CS who
don’t quickly stabilize with pharmacologic therapy
Class II b
Alternative LV assist device may be considered in pt
with refractory CS
30. Anaphylactic shock
• What is anaphylaxis??
A manifestation of immediate hypersensitivity
A sensitized individual to
A specific antigen results in
life-threatening respiratory distress
followed by vascular collapse and shock
accompanied by pruritis, urticaria, and
angioedema
31. Etiology
• Medications, including antibiotics (especially penicillin
and sulfa), vaccines, opiates, aspirin, NSAIDs, local
anesthetics, intravenous fluids with dextran, and insulin
• Foods, such as nuts, milk, eggs, soy, wheat, and
seafood
• Stings by fire ants and Hymenoptera species (eg, bees,
wasps, yellow jackets, hornets)
• Latex
• Blood products, including plasma, immunoglobulin,
cryoprecipitate, and whole blood
• Idiopathic origins
• Exercise causes
36. Obstructive shock
• Extra-cardiac obstruction to flow in the
cardiovascular circuit
• Either impairment of diastolic filling or excessive
afterload
Etiology
- Tension pneumothorax
- Pericardial tamponade
-Massive Pulmonary embolus
-IVC Obstruction
DVT
Gravid uterus on IVC
Neoplasm
-Increased intrathoracic pressure
Excess positive end expiratory pressure
neoplasm
37. • Develops when a lung or chest wall injury is such that it
allows air into the pleural space but cannot out of it (a
one way valve)
• As a result
- Air accumulation & compress the lung
- Shifting the mediastinum
- Compressing contralateral lung
- Increasing intrathoracic pressure
- Reduce Venus return to the heart
- Causes shock
Tension pneumothorax
41. NEUROGENIC SHOCK
• A type of distributive shock that results from the loss or
suppression of sympathetic tone
• Causes massive vasodilatation in the venous vasculature
→ ↓venous return to heart → ↓cardiac output
• Most common etiology: Spinal cord injury
**Neurogenic shock is the rarest form of
shock
42. Causes of Neurogenic Shock
The Common Causes Of Neurogenic Shock Include:
• Blunt or penetrating injury to the spinal cord
• Trauma to the spinal cord from
motor vehicle accidents, sports injuries, falls, stab
and gunshot wounds.
• Improper administration of regional anesthesia can
also cause neurogenic shock.
• Devastating head injury
• Drugs and medications which affect the autonomic
nervous system can also cause neurogenic shock.
43. Pathophysiology of Neurogenic Shock
Disruption of sympathetic nervous system
Loss of sympathetic tone
Venous and arterial vasodilation
↓ venous return
↓ stroke volume
↓ cardiac output
↓ cellular oxygen supply
↓ tissue perfusion
Impaired cellular metabolism
44. Assessment of Neurogenic Shock
• PATIENT ASSESSMENT
-Hypotension
-Bradycardia
-Hypothermia
-Warm, dry skin
- ↓CO
-Flaccid paralysis below level of the spinal lesion
45. Patient Also Experiences
-SOB , rapid and deep shallow breathing.
-Facial pallor, Dizziness, lightheadedness, fainting.
-Nausea and vomiting.
- weakness due to insufficient blood supply.
-may changes in mental state or disorientation.
-Has bluish discoloration of lips and fingers (cyanosis).
-Decreased or absent urine output.
-Sweats profusely.
-Considerable chest pain
-Loss of consciousness
46. Treatment For Neurogenic Shock
• Neurogenic shock is a serious condition
• Requires emergent medical care
• Airway, Breathing and Circulation (ABC)
• Immobilize the patient, especially the spinal region
to prevent any further damage to the spinal cord.
• IV fluids to stabilize the patient's blood pressure
• Inotropic agents, such as dopamine may be infused
for fluid resuscitation, if needed.
• Atropine is given intravenously to manage severe
bradycardia.
• Surgery is needed in case of accident/trauma/ injury/
to the patient
47. Spinal shock Vs Neurogenic
Acute spinal cord injury Hemodynamic phenomenon
Loss of vasomotor tone &
sympathetic tone
Peripheral neurons become
temporarily unresponsive to
brain stimulation
Disruption of autonomic
pathways → Loss of
sympathetic tone →
vasodilatation
C/F: Decreased reflexes
Loss of sensation
Flaccid paralysis below
level of injury
Hypotension
Bradycardia
Poikilothermia
Last days to months (transient) May last up to 6wks
