Shock: Clinical features and pathophysiology - PowerPoint PPT Presentation

1 / 35
About This Presentation
Title:

Shock: Clinical features and pathophysiology

Description:

Shock: Clinical features and pathophysiology Mahesh Nirmalan Critical Care Unit, Manchester Royal Infirmary Objectives Life-threatening condition Immediate or delayed ... – PowerPoint PPT presentation

Number of Views:695
Avg rating:3.0/5.0
Slides: 36
Provided by: melissa165
Category:

less

Transcript and Presenter's Notes

Title: Shock: Clinical features and pathophysiology


1
Shock Clinical features and pathophysiology
  • Mahesh Nirmalan
  • Critical Care Unit, Manchester Royal Infirmary

2
Objectives
  • Life-threatening condition
  • Immediate or delayed mortality
  • Multiple aetiology
  • Recognition and Assessment
  • Physiological consequences of shock
  • clinical features
  • Document and report on progression

3
Definition of Shock
  • Inadequate tissue perfusion
  • Decreased oxygen supply
  • Anaerobic metabolism
  • Accumulation metabolic waste

4
Causes of Shock
  • Severe or sudden blood loss
  • Large drop in body fluids
  • Myocardial infarction
  • Major infections
  • High spinal injuries
  • Anaphylaxis
  • Extreme heat or cold

5
Types of Shock
  • Hypovolemic Shock
  • haemorrhagic
  • or non haemorrhagic
  • Other causes of shock
  • Cardiogenic Shock
  • Septic Shock
  • Neurogenic Shock
  • Anaphylactic Shock

6
Harvest of Death T H OSullivan
7
Hypovolaemic Shock
  • Haemorrhage Overt or occult
  • Reduction in circulating volume
  • Reduction in venous return and CO
  • O2 supply-demand imbalance
  • Lactic acidosis
  • Reduction in venous oxygen saturation
  • Non haemorrhagic hypovolaemia
  • Severe burns, vomiting and diarrhoea

8
CO, MAP and SvO2
9
Effect of EDV and contractility on SV
10
Changes in CO and MAP in haemorrhage
11
Clinical Signs of Acute Hemorrhagic Shock
12
Signs of Shock
  • Cold, clammy and pale skin
  • Rapid, weak, thready pulse
  • Shallow, rapid breathing
  • Oliguria
  • Reduction in MAP
  • Cyanosis
  • Loss of consciousness

13
Non-Haemorrhagic Shock
  • Cardiogenic Shock
  • Septic Shock
  • Neurogenic Shock
  • Anaphylactic Shock

14
Cardiogenic Shock
  • Primary myocardial failure
  • Arrhythmia
  • Tamponade
  • Contusion
  • Pump failure
  • Reduction in cardiac output
  • Decreased blood supply
  • Decreased oxygen delivery

15
Cardiogenic Shock
  • Assess for
  • Signs of heart failure
  • Signs of tamponade
  • Cardiac dysrrhythmia
  • Myocardial infarction
  • Tachycardia
  • Muffled heart sounds or third heart sound
  • Engorged neck veins with hypotension
  • Dyspnoea
  • Oedema in feet and ankles

16
Septic Shock
  • Bacterial, viral, fungal infection
  • Gram negative and gram positive bacteria
  • High output failure warm shock
  • Fever, tachycardia, tachypnoea, leucocytosis
  • Inadequate oxygen extraction
  • High SvO2, Metabolic acidosis
  • Cold shock
  • Atypical presentation in immuno-compromised
    patients
  • Diabetes, Cirrhosis, immunosuppression

17
Septic Shock in trauma patients
  • Develops 2 - 5 days after injury occurs
  • Carries a poor prognosis
  • Assess for
  • Penetrating abdominal injuries
  • Signs of infection
  • Warm pink skin and dry elevated body temperature
  • Tachycardia
  • Wide pulse pressures

18
Neurogenic Shock
  • Caused by
  • Spinal cord injury
  • Certain drugs
  • Brain stem, spinal or torso trauma
  • Venous pooling and arteriolar dilatation
  • Signs and Symptoms
  • Hypotension without tachycardia
  • Warm pink skin
  • Low blood pressure minimal response to fluids

19
Anaphylactic shock
20
Anaphylactic Shock
  • Rapid onset
  • Primary systems
  • Cardiovascular, Respiratory
  • Skin, Gastrointestinal, coagulation
  • Face, pharynx and laryngeal oedema
  • Adrenaline is life saving

21
Anaphylactic Shock
  • Diffuse vasodilatation
  • Increase size of vascular bed
  • Blood is trapped in small vessels and viscera
  • Temporary loss in total circulatory volume
  • Sudden severe allergic reaction to
  • Drugs, Toxins, Foods, Plants

22
Symptoms
  • Apprehension and flushing
  • Wheezing or shortness of breath cough
  • Rapid, weak pulse
  • Cyanosis
  • Generalized itching or burning
  • Watering and itching of the eyes
  • Hypotension
  • Coma

23
Stages of shock
  • Compensated shock
  • Autotransfusion
  • Decompensated shock
  • Blood moves to more vital organs
  • Irreversible shock
  • Multiple system / organ damage
  • Even with treatment, death is the result

24
Plasma Lactate
A priori groups
Post hoc groups
25
Evaluation of Shock
  • Internal or external hemorrhage
  • Underlying cardiac problems
  • Sepsis
  • Trauma to spine cord
  • Contact with known allergic substance
  • Determine amount of blood loss
  • How long has casualty been bleeding?

26
Level of Consciousness
  • Report and record
  • Alert
  • Verbal response to stimuli
  • Pain response to stimuli
  • Unresponsive to any stimuli

27
Early Signs of Shock in Non Complicated Patients
  • High index of suspicion
  • Minimum tachycardia
  • No measurable changes occur in blood pressure
  • Pulse pressure is potentially very useful

28
Definitive management
  • Where?
  • By whom?

29
Invasive monitoring
  • Essential in the definitive treatment
  • Direct arterial pressure
  • Central venous pressure
  • Cardiac output

30
Direct arterial pressure
31
CVP AND CIRCULATING VOLUME?
32
Treatment of Shock
Increase tissue perfusion and oxygenation status
  • Maintain airway
  • Control bleeding
  • Baseline vital signs
  • Level of consciousness

33
Treatment of Shock
  • Positioning
  • ABCD approach
  • Fluid therapy
  • Drug therapy
  • Keep patient at normal temperature
  • Prevent hypothermia
  • Minimize effect of shock
  • On-going assessment - every 10-15 minutes

34
Specific measures
  • Hypovolaemia Blood transfusion
  • Electrolyte/acid base imbalance
  • Sepsis Antibiotics, ?steroids
  • Neurogenic Steroids
  • Anaphylactic Adrenalin

35
Summary
  • Life threatening Early goal directed therapy and
    regular monitoring by trained staff will change
    outcome.
  • Early detection DONT RELY ON BP
  • High index of suspicion
  • Monitor casualties susceptible to shock
Write a Comment
User Comments (0)
About PowerShow.com