Week 2 - Shock And Stabilization Flashcards
Name conditions associated with distributive shock?
SIRS/Sepsis
Anaphylaxis/Anaphylactoid
Neurogenic
Neurogenic
Name conditions associated with obstructive shock?
Cardiac tamponade
Pleural space disease (effusion, pneumothorax, diaphragmatic hernia)
Pulmonary thromboemboli
GDV
What conditions are associated with non-circulatory shock?
Metabolic - mitochondrial dysfunction
Decreased O2 content - anaemia, Hb impairment
What is the equation for cardiac output?
Stroke volume x heart rate
What equation is this?
(SaO2 x Hb (g/l) x 1.37) + (PaO2 (mmHg) x 0.003
CaO2 - arterial oxygen content (ml/L)
What is the equation for delivery of oxygen DO2?
CO x CaO2
What is hypoxia?
Inadequate DO2 to meet the VO2 of the body
What are the 4 causes of hypoxia?
Decreased inspired O2
Inadequate tissue perfusion
Increased O2 demand
Cellular inability to DO2
What is the oxygen extraction ratio?
VO2 / DO2
What is critical O2 delivery?
O2 decreased, cells switch from aerobic to anaerobic metabolism.
What is hypoxemic hypoxia?
Decreased DO2 due to decreased CaO2 secondary to hypoxaemia from a decreased PaO2 and SaO2.
What is hypaemic hypoxia?
Decreased Hb thus reduces CaO2 thus decreasing DO2.
What is haemoglobinopathy?
Adequate Hb but Hb dysfunctional and unable to transport O2 sufficiently.
What is Stagnant/circulatory hypoxia?
Low CO and low blood load, leading to decreased DO2.
What is histotoxic hypoxia?
Adequate DO2 but tissues unable to extract and utilise O2.
Name a condition associated with histotoxic hypoxia?
Cyanide toxicity
Carbon monoxide toxicity
Mitochondrial dysfunction - Sepsis
What is metabolic hypoxia?
Adequate DO2 but increased VO2 demand (not enough to go around).
E.g. sepsis
Define shock.
VO2 exceeds DO2 and cells enter anaerobic metabolism.
What is dysoxia?
Cells unable to utilise O2 (Hisotoxic hypoxia).
What is apoptosis?
Cell death - leads to organ failure.
What is hypovolaemic shock?
Reduced volume in the intravascular space leading to decreased preload and cardiac output.
What is relative hypovolaemic shock?
Internal fluid shift from intravascular space e.g. internal haemorrhage, third spacing, massive vasodilation -sepsis.
What is absolute hypovolaemic shock?
External haemorrhage, excessive fluid loss e.g vomiting, diarrhoea, polyuria, endocrine disease.
What is distributive shock?
Systemic vasodilation