Shock Flashcards
What are the different types of shock?
– Hypovolaemic (this is the only type of haemorrhagic shock)
– Cardiogenic – Septic – Distributive
– Neurogenic – Anaphylactic – Obstructive
– Psychogenic
What is hypoxia?
An abnormal state of the circulation, in which tissue blood flow is reduced.
What is shock?
• An arterial systolic BP< 90 mmHg or a mean arterial pressure of 90 mmHg or MAP > 70 mmHg or
• A state of cardiovascular dysfunction resulting in a generalised inadequacy of tissue perfusion relative to metabolic requirements
= LACTIC ACIDOSIS (anaerobic metabolism)
What’s the management of shock?
• ABCDE
• Support Physiology – (Fluids, Oxygen, Ventilation)
• Identify a Cause – (Signs & Symptoms, Investigations)
• Definitive Treatment • Re asses at all levels
The therapeutic aims are:
• Resolution of lactic acidosis • No tissue ischaemia • Preload / afterload optimal to optimise CO • BP to maintain adequate organ perfusion • Urine output > 0.5 ml/kg/hr
What’s an inotrope?
A drug that increases myocardial contractility. They’re administered to improve myocardial performance as adjuncts to adequate fluid resuscitation in the management of tissue hypoxia and to maintain both perfusion pressure and blood flow to organs.
What are alpha-1 and beta-1 and beta-2 adrenoceptors and dopaminergic receptor?
alpha-1: located in smooth muscle cell membrane and promotes contraction of the smooth muscle of the peripheral blood vessels they are stimulated for peripheral vasoconstriction.
beta-1: located in cardiac muscle cell membrane, and if stimulated increases heart rate and cardiac contractility.
beta-2 receptor: • Found in vascular smooth muscle • Secondary messenger: ↑ cAMP • Relaxation of bronchial smooth muscle • Promotes glycogenolysis
dopaminergic receptor: mediates relaxation of vascular smooth muscle in renal and splanchnic beds
How can you assess shock?
- Heart Rate • Blood Pressure • Consciousness • Skin
- Temperature • Neurological Function • Urine Output
- Bloods • Blood Gas • Trauma Radiography/CT • Fluid Bolus • Blood Cultures • Catheter • Central Monitoring
What is cardiogenic shock?
• Inability of the heart to pump enough blood to perfuse the body. Causes: Direct Myocardial damage: -Ischaemic/MI -Cardiomyopathy -Myocarditis -Trauma Inhibition of Contraction: -Local anaesthetics -Antiarrythmics -B blockers -Anaphylaxis -Sepsis
What is sepsis? Treatment?
- systemic response to infection
- induced by presence of pathogenic micro- organisms OR
- release of toxic products from focal infection OR in response to non-infective conditions such as trauma, pancreatitis, post-CPB
Treatment: • Supportive • Fluids • Vassopressors • Organ Support • Activated protein C • Survivng Sepsis Campaign SCCM
What is a Systemic Inflammatory Response (SIRS)?
2 OR MORE OF THE FOLLOWING:
Core temperature: < 36oC or > 39oC
Tachycardia defined by: Heart rate > 90 beats/min. in the absence of beta-blocking drugs
Tachypnoea defined by
Respiratory rate > 20 breaths/min. OR
PaCO2 < 4.3 kPa (32 mm Hg) during spontaneous Ventilation OR the requirement for mechanical ventilation
WBC count > 12 or < 3 x 109/l OR > 10% immature (band) forms
What is septic shock?
- Arterial hypotension (systolic arterial BP < 90mmHg or mean arterial BP < 60mmHg) with associated signs of tissue hypoperfusion
- Increased blood lactate > 2 mmol l-1
- Altered organ perfusion -oliguria, mental obtundation etc.
What is neurogenic shock?
• Vasomotor paralysis below the level of the injury resulting in decreased peripheral vascular resistance.
• Sympathetic impulses which would normally stimulate vasoconstriction are interrupted, leading to widespread vasodilation.
• Blood collects in the capillary beds reducing venous return, cardiac output, and blood pressure.
Signs:
• Hypotension • Bradycardia • Low Temperature (Spinal Level)
Treatment:
Oxygen, Fluids, Vassopressors
What’s the treatment of anaphylactic shock?
- Adrenaline • Oxygen • Fluids • Steroids
* Antihistamines • B agonists
