10. Haemodynamic Shock Flashcards
What are the 3 main types of shock that result in reduced CO?
- cardiogenic
- mechanical
- hypovolaemic
What are 3 potential causes of cardiogenic shock?
- MI/heart Ischaemia
- arrhythmias
- acute worsening of heart failure
In cardiogenic shock what will happen to the CVP?
May increase or be normal
What is happening to the patient if there is pulseless electrical activity?
Cardiac arrest
What is long QT syndrome?
They are more at risk of getting..?
Rare, congenital/acquired syndrome where there is a delayed repolarisation of the heart
Ventricular fibrillation
&
Torsades de pointes (abnormal heart rhythm)
What is cardiac tamponade?
Blood/fluid building up in the pericardial space
What are two causes of mechanical shock?
Cardiac tamponade
Massive Pulmonary embolism
How does cardiac tamponade cause mechanical shock?
Restricts filling of the heart in diastole.
In cardiac tamponade which side of the heart is effected?
Both
What happens to the CVP in mechanical shock ?
What happens to the arterial pressure ?
Increases
Low
If a PE was to cause mechanical shock where would it lodge ?
Large pulmonary artery
In Mechanical shock caused by PE what happens to the pressure in the right and left side of the heart?
Left = low Right = high
If someone has a PE what sx would they get?
Dyspnoea
Chest pain
What can cause hypovolaemic shock?
Haemorrhage
Severe burns
Severe diarrhoea or vomiting
What percentage of blood loss will show signs of shock ?
20-30%
What percentage of blood loss is severe shock?
30-40%
What is the compensatory response for shock ?
- increased sympathetic stimulation via baroreceptors = - peripheral vasoconstriction -venoconstriction - tachycardia - increased force of contraction
What is internal transfusion ?
Seen in hypovolaemic shock.
Reduced hydrostatic pressure in the capillaries causes fluid to move out of the tissue space and into the capillaries.
How might a patient with hypovolaemic shock present?
Tachycardia
Weak pulse
Pale skin
Cold, clammy extremities
What are longer term responses to restore blood volume?
- RAA system
- ADH
If there is 20% blood volume loss how long will it take to restore?
3 days if salt and water are adequate
What is the type of shock caused by reduced TPR
Distributive shock
What are two examples of distributive shock ?
Toxic/septic shock
Anaphylactic shock
What happens to the vessels in distributive shock ?
What happens to the arterial pressure?
Vasodilation
Decrease
