Shock

Question 1

Definition of septic shock

Answer 1

• Infection that triggers a particular SIRS response
• If patients develop organ failure and refractory hypotension this is septic shock

Question 2

Definition of haemorrhagic shock

Answer 2

• Class I shock would be completely compensated for.
• Class II shock would cause tachycardia.
• Class III shock causes tachycardia and hypotension as well as confusion.
• Class IV shock causes loss of consciousness as well as severe hypotension.

Question 3

Definition of neurogenic shock

Answer 3

• Most commonly occurs following spinal cord transection (usually at a high level)
• Resultant interruption in autonomic nervous system and so either decreased sympathetic tone or increased parasympathetic tone
• This leads to a decrease in peripheral vascular resistance mediated by marked vasodilation

Question 4

Definition of cardiogenic shock

Answer 4

• Main cause is IHD or direct myocardial trauma or contusion
• Pump failure
• ECG changes common

Question 5

Definition of anaphylactic shock

Answer 5

• Severe, life-threatening, generalised or systemic hypersensitivity reaction

Question 6

Management of septic shock

Answer 6

• Sepsis 6
• Consider vasopressors

Question 7

Management of haemorrhagic shock

Answer 7

• Control bleeding
• Normalise circulating volume (fluids - titrate to urine output, CVP, BP)
• Transfuse to maintain Hb level of 7-8 (no risk factors for tissue hypoxia) or Hb level of 10 (those with risk factors for tissue hypoxia)
• Haemodialysis if ATN

Question 8

Management of neurogenic shock

Answer 8

• Vasopressors for peripheral vasoconstriction
• IV fluids to increase circulating volume
• Inotropes to increase contraction of myocardium and so increase BP

Question 9

Management of cardiogenic shock

Answer 9

• Largely supportive
• Treat arrhythmias/MI if cause
• Consider dobutamine
• Transthoracic ECHO to determine evidence of pericardial fluid or direct myocardial injury
• Measurement of troponin levels may be undertaken
• If cause is blunt injury associated with cardiogenic shock the right side of the heat is most likely site of injury - these patients require surgery to repair defects and will need cardiopulmonary bypass to achieve this, intra-aortic balloon pumps can also be used as a bridge to surgery