GEP (Life Support) Week 2 Flashcards
What is the mediastinum and how is it seperated?
The Mediastinum: The middle compartment within your thoracic cavity, between your lungs. It contains the heart and other important structures and is sub-divided into the Superior mediastinum, posterior mediastinum, anterior mediastinum and middle mediastinum.
the superior and posterior mediastinum is seperated by the sternal edge at T4.
What are the boarders and content of the superior mediastinum?
What are the boarders and content of the Anterior mediastinum?
What are the boarders and content of the Posterior mediastinum?
What are the boarders and content of the Middle mediastinum?
Identify the anatomy of the heart
Atrioventricular Valves:
Tricuspid & Mitral
Semilunar Valves:
Pulmonary & Aortic
Describe the blood blow around the body
Conduction system of the heart
Describe SA node conduction
Phase 0 – Depolarisation
Once threshold of -40 is reached, VGCCs open. Ca influx = faster rate of depolarisation.
Phase 3 – Repolarisation
“Resets” the action potential. K channels open and efflux out of the cell.
Phase 4 – Pacemaker potential
Slow depolarisation of the pacemaker cell. When it reaches the threshold, an action potential is fired.
Describe myocyte conduction part 1
Describe myocyte conduction part 2
Describe the cardiac cycle and the different points?
What controls BP
CVS: Heart and blood vessels, Salt and water reabsorbtion
Nervous system: Sympathetic and parasympathetic
Endocrine: RAAS system, ADH, ANP
Name the structures related to the CVS and the receptors involved and whether it is SNS or PNS.
What are the 4 ways that SNS controls BP
-Chronotropic effect– SA node - Increase the rate of action potentials which increases the HR.
-Inotropic effect– Atrial/ventricular myocytes - Increase in calcium in the myocytes which increases contractility.
-Lusitropic effect - Atrial/ventricular myocytes – Speed up the relaxation of the myocytes
-Dromotropic – AV node - Increased rate of impulse through atria to ventricle to maintain cardiac output