SHOCK

1
Shock Dr.Hadeel AlOtair ABIM,MRCP,FCCP
2
Outline

• Definition mechanism of shock.
• Consequences of Shock.
• How to diagnose shock?
• Classification of Shock.
• Causes of various types of shock
• Basic principles in management of shock.

3
Shock

• Reduction of effective tissue perfusion leading
  to cellular and circulatory dysfunction

4
Shock

• The Aim of perfusion is to achieve adequate
  Cellular Oxygenation
• This requires
• Red Cell Oxygenation
• Red Cell Delivery To Tissues

Fick Principle
5
Fick Principle

• Airs gotta go in and out.
• Bloods gotta go round and round.
• Any variation of the above is not a good thing!

6
(No Transcript)
7
Shock

• Red Cell Oxygenation
• Oxygen delivery to alveoli
• Adequate FiO2
• Patent airways
• Adequate ventilation

8
Shock

• Red Cell Oxygenation
• Oxygen exchange with blood
• Adequate oxygen diffusion into blood
• Adequate RBC mass/Hgb levels
• Adequate RBC capacity to bind O2
• pH
• Temperature

9
Shock

• Red Cell Delivery To Tissues
• Adequate perfusion
• Blood volume
• Cardiac output
• Heart rate
• Stroke volume (pre-load, contractility,
  after-load)
• Conductance
• Arterial resistance
• Venous capacitance

10
(No Transcript)
11
(No Transcript)
12
Shock

• Red Cell Delivery To Tissues
• Adequate RBC mass
• Adequate Hgb levels
• Adequate RBC capacity to unbind O2
• pH
• Temperature

13
Consequencies of Shock

• Inadequate oxygenation or perfusion causes
• Inadequate cellular oxygenation
• Shift from aerobic to anaerobic metabolism

14
ANAEROBIC METABOLISM
Glycolysis Inefficient source of energy
production 2 ATP for every glucose produces
pyruvic acid
15
AEROBIC METABOLISM
Glycolysis Inefficient source of energy
production 2 ATP for every glucose produces
pyruvic acid Oxidative phosphorylation Each
pyruvic acid is converted into 34 ATP
16
Anaerobic Metabolism

• Occurs without oxygen
• oxidative phosphorylation cant occur without
  oxygen
• glycolysis can occur without oxygen
• cellular death leads to tissue and organ death
• can occur even after return of perfusion
• ? organ dysfunction or death

17
Ultimate Effects of Anaerobic Metabolism
18
Shock

• Markers Of Hypoperfusion
• ?S.Lactate
• Perfusion related acidemia
• Hypotension

19
Maintaining perfusion requires

• Volume
• Pump
• Vessels
• Failure of one or more of these causes shock

20
Shock Syndromes

• Hypovolemic Shock
• blood VOLUME problem
• Cardiogenic Shock
• Blood pump problem
• ObstructiveShock
• Filling Problem
• Distributive Shock
• blood VESSEL problem

21
Hypovolemic Shock

• ( Loss of Volume)

• Burns
• _Diarrhea
• Vomiting
• Diuresis
• Sweating
• Third space losses
• Pancreatitis
• Peritonitis
• Bowel obstruction

• blood loss TraumaBLOOD YOU SEE
• BLOOD YOU DONT SEE
• Non-traumatic
• Vaginal
• GI
• GU
• Fluid loss
• (Dehydration)

22

• History
• Physical Examination

23
Signs

• Due to Hypoperfusion
• Altered mental state
• Impaired capillary filling
• ?Urine output
• Skin temperature cold clammy
• BP(narrow pulse pressure, Postural?BP)
• Low volume pulse
• Skin colourperipheral cyanosis
• Compensatory responses
• _ Tachycardia,
• _ pallor

24
Key Issues In Shock

• Recognize Treat during compensatory phase

Restlessness, anxiety, combativeness Earliest
signs of shock
Best indicator of resuscitation effectiveness
Level of Consciousness
25
Hypovolemic Shock management

• goal Restore circulating volume, tissue
• perfusion correct cause
• Airway Breathing
• Control bleeding
• Elevate lower extremities
• Avoid Trendelenburg

26

• Two large bore IV lines/central line
• Fluids / Blood Products /vasopressors
• Target arterial BP SBP 90 mmHg
• - MAP 65
  mmHg.
• Bladder catheter
• Arterial Cannulation

27
Key Issues In Shock

• Tissue ischemic sensitivity
• Heart, brain, lung 4 to 6 minutes
• GI tract, liver, kidney 45 to 60 minutes
• Muscle, skin 2 to 3 hours

Resuscitate Critical Tissues First!
28

• Consequence Of Volume Loss
• 15750ml- compensatory mechanism
• maintains cardiac output
• 15-30 750-1500ml-,
• decreased BP urine output
• 30-40 1500-2000ml -Impaired compensation
• profound shock along with severe acidosis
• 40-50 - refractory stage

29
Shock

• Cardiogenic Shock Pump Failure

Myopathic M I CHF Cardiomyopathy Arrhythmic Tachy
or bradyarrhythmias

• Mechanical
• Valvular Failure
• HOCM

30
Cardiogenic Shock

• History Chest pain, Palpitations,SOB
• RHD,IHD
• Physical exam
• Signs of ventricular failure
• HeartMurmurs,S3,S4

31
Cardiogenic Shock

• Supine, or head and shoulders slightly elevated,
  do NOT elevate lower extremities
• Treat the underlying cause if possible
• examples

32

• Treat rate, then rhythm, then BP
• Correct bradycardia or tachycardia
• Correct irregular rhythms
• Treat BP
• ?Cardiac contractility(inotropes)
• Dobutamine, Dopamine

33
Distributive Shock

• Inadequate perfusion of tissues due to
  mal-distribution of blood flow
• (blood vessels problem)
• Cardiac pump blood volume are normal but blood
  is not reaching the tissues

34
Distributive Shock

• Septic Shock
• Anaphylactic Shock
• Histamine is released
• Blood vessels
• Dilate (loss of resistance)
• Leak (loss of volume)
• Extravascular smooth muscle spasm
• Laryngospasm
• Bronchospasm
• Neurogenic/Vasogenic(spinal cord)
• Endocrinologic

35
Sepsis Septic shock
36
Septic Shock management

• A B C,
• Assist ventilation Augment Oxygenation
• Monitor Tissue perfusion-
• Restore Tissue perfusion-
• IVFluids, Vasopressors
• Identification Eradication of septic foci
• Specific Therapies
• -

37
Neurogenic Shock

• Patient supine lower extremities elevated
• Avoid Trendelenburg
• Infuse isotonic crystalloid
• Maintain body temperature

38
Anaphylactic Shock

• Suppress inflammatory response
• Antihistamines
• Corticosteroids
• Oppose histamine response
• Epinephrine
• bronchospasm vasodilation
• Replace intravascular fluid
• Isotonic fluid titrated to BP 90 mm

39
Obstructive shock

• Impaired diastolic filling
• Cardiac tamponade
• Constrictive pericarditis
• Tension pneumothorax
• Increased ventricular afterload
• Pulmonary embolism

40
Obstructive Shock

• Treat the underlying cause
• Tension Pneumothorax
• Pericardial Tamponade
• anticoagulation
• Isotonic fluids titrated to BP w/o pulmonary
  edema
• Control airway
• Intubation

41
Key Issues In Shock

• Falling BP LATE sign of shock
• BP is NOT same thing as perfusion
• Pallor, tachycardia, slow capillary refill
  hypoperfusion, until proven otherwise

42
Shock Management

• Avoid vasopressors until hypovolemia ruled out,
  or corrected

Squeezing partially empty tank can cause
ischemia, necrosis of kidney and bowel
43
THANK YOU
44
Hypovolemic Shock

• Fluid loss Dehydration
• Nausea vomiting, diarrhea, massive diuresis,
  extensive burns
• Blood loss
• trauma blunt and penetrating
• BLOOD YOU SEE
• BLOOD YOU DONT SEE

45
Shock

• Determinants OF Effective Tissue Perfusion
• Cardiovascular performance(cardiac output)
• Preload
• Afterload
• Contractility
• Heart rate
• Distribution of cardiac output
• Microvascular function
• Local oxygen unloading diffusion in the tissue

46
(No Transcript)
47
Initial Management Hypovolemic Shock

• goal Restore circulating volume, tissue
• perfusion correct cause
• Arrest ongoing blood loss
• Early Recognition- Do not relay on BP! (30 fld
  loss)
• Restore circulating volume
• - IV fluids 1-2
  ltr-Crystalloid VS Colloids
• - Blood Products