Clinical Shock

What are the types of shock?

• Hypovolaemic

• Distributive

• Cardiogenic

• Obstructive

• Dissasiative

Define clinical shock

Loss of fluid which means cells not able to be perfused with oxygen

Describe Hypovolaemic Shock

Acute loss of circulating blood volume

Can be caused by:

• Severe haemorrhage (internal or external) where whole blood volume is lost

• Extensive burns - serum is lost

• Severe diarrhoea ± Vomiting - water and electrolytes are lost

Describe Distributive Shock

• Caused by widespread dilation of peripheral vascular system

• Created effect of larger container for same blood volume

• Cases of sepsis/anaphylaxis this creates ‘leaky’ blood vessels allowing fluid to move into interstitial space

Describe Cariogenic shock

Caused by heart being unable to circulate sufficient blood to meet the body’s metabolic needs

• Most common following a myocardial infarction

• Acute heart failure

• Arrhythmia

  • Pulsed VT

Describe Obstructive shock

Uncommon cause of shock caused by an obstruction in the flow to/from the heart. Often caused by:

• Tension pneumothorax - air/lung itself push against heart

• Cardiac tamponade

• Pulmonary embolism - if obstructive flow to pulmonary veins

Describe Dissociative shock

• Caused by:

  • Oxygen carrying capacity of blood affected by inadequate number for red blood cells able to carry sufficient oxygen

  • Competing molecules take up space of RBCs

• Causes:

  • Anaemia (haemoglobin levels reduced)

  • Carbon monoxide poisoning

Describe signs and symptoms of shock

• HR increase to try to compensate

• RR increase to try to compensate

• Altered level of consciousness (hypoxia due to low blood volume or hypoxaemia)

• Pale, cold extremities, delayed cap refill (blood going to vital organs)

• Sweating, dilated pupils, thirst

• Bradycardia if decompensating

What should you consider for certain patients who have signs and symptoms of shock?

Certain pat groups may not have abnormal signs until significant 1-1.5l has been lost

• Young, athletic healthy people

• Pregnant patients

• Patients on beta blocker (slow hr even if other signs and symptoms abnormal)

How do we manage shock?

• Assess for time critical ABCD

• Administer high % oxygen

• If conscious, position patient flat

• Consider raising lower limbs (to combat low BP)

• If unconscious put in stable side position

• Treat other injuries and bleeding

• Constant obs, manage temperature, gentle handling, reassurance