Cardiovascular

• Capillaries exchange fluid between blood and interstitial space
• Mediastinum is where the heart is located
• Pericardium is a double walled sac around the heart, protecting it
• Atria receive blood from veins and sends blood to the ventricles
• Ventricles receive blood from the atria and send blood to the arteries
• Right side of heart deals with deoxygenated blood
• AV valve is a one way flow of blood from the atria to ventricles
• Semilunar valves are one way flow from ventricles to the pulmonary artery or the aorta
• Tricuspid valve separates right atria and ventricle
• Bicuspid (mitral) valve separates left atria and ventricle
• Valves of the heart control one way blood flow
• Deoxygenated blood goes from the body to the heart to the lungs
• Oxygenated blood goes from the lungs to the heart to the body
• Blood flow through the heart begins with deoxygenated blood going through the right atrium to the SVC and IVC, then through the tricuspid valve, the right ventricle, through the pulmonary valve, into the lungs - oxygenated blood enters through the left atrium, then through the mitral valve, into the left ventricle, through the aortic valve and out to the body
• Coronary vessels supply the heart with oxygen and nutrients
• Systole occurs when the ventricles contract and send blood out to the body
• Diastole occurs when the ventricles relax and fill up with blood
• An action potential is an explosion of electrical activity that is created by a depolarizing current causing a contraction (systole)
• 1 cardiac cycle is depolarization, contraction, repolarization, relax
• The SA node is the pacemaker of the heart
• The electrical conduction system of the heart begins in the SA node, to the AV node, bundle branches, to the Purkinje fibers
• The electrical conduction system of the heart determines when systole and diastole occurs
• EKGs are the sum of all the action potentials of the heart
• The P wave represents atrial depolarization
• The QRS complex represents ventricular depolarization
• The T wave represents ventricular repolarization
• 5 boxes on an EKG is 0.20 seconds
• Normal PR interval is 0.12-0.20 seconds
• Normal QRS is less than 0.12 seconds
• Causes of a flutter are heart disease, MI, CHF, and pericarditis
• Interventions for a flutter include cardioversion, pacing, amiodarone, metoprolol, or diltiazem
• Causes of a fib include heart disease, pulmonary disease, stress, alcohol, or caffeine
• Interventions for a fib include cardioversion, ablation, amiodarone, metoprolol, or diltiazem
• Causes of v tach include MI, ischemia, digoxin toxicity, hypoxia, acidosis, hypokalemia, hypotension
• V tach with a pulse is cause for cardioversion
• Pulseless v tach requires CPR, epi, defibrillation
• The QRS in v tach is wide and bizarre
• V fib is the most common cause of sudden death
• Causes of v fib include MI, ischemia, hypoxia, acidosis, hypokalemia, hypotension
• Interventions for v fib include CPR, epi, defibrillation