Heart and Neck Vessels Flashcards
Explain the cardiac cycle… the diastole half
In diastole, the ventricles are relaxed and the AV valves are open: tricuspid and mitral valve
Blood flows into the chambers of the heart
Toward the end of diastole, the atria contract to push more blood into the ventricles. This is the atrial kick
Explain the cardiac cycle.. systole half
In systole, the AV valves slam shut because pressure in the ventricles are high
The closing of the AV valves creates the S1 heart sound
The ventricles contract, pushing blood through the aortic and pulmonic semilunar valves
Once blood has left the ventricles, the semilunar valves slam shut, creating S2 heart sounds.
What is the S1 heart sound?
Occurs when the AV valves close
Signals beginning of systole
Usually heard loudest over apex
Should sound crisp and clear: LUB
coincides with carotid artery pulse
Coincides with R wave one the ECG
What is the S2 sound?
Occurs when the semilunar valves close
Signals end of systole
Usually heard loudest over base
Should sound clear and crisp: DUP
What is S3
Occurs immediately after S2, when resistance to ventricular filling creates a vibration. Low pitched like distant thunder.
Can be normal or abnormal (pathologic)
Can be the earliest sign of heart failure
What is S4
Occurs just before S1, during atrial kick when resistance to ventricular filling creates a vibration. Low pictured and soft.
Can be a sign of coronary artery disease or cardiomyopathy.
What are murmurs?
Created when blood flow through the chambers of the heart is turbulent. It is a gentle, blowing or swooshing sound.
What are some causes of murmurs?
Increased velocity of blood
Decreased viscosity of blood
Structural defects in valves or heart chambers
Formula for cardiac output
Cardiac output equals the volume of blood ejected during systole ( stroke volume ), multiplied by the number of heartbeats per min (rate)
CO= SV x R
What is preload?
The volume of blood that fills the ventricles during diastole
What is afterload?
The pressure that the ventricles must pump against
Where are the carotid arteries?
Located on each side of the neck in the groove between the trachea and the sternomastoid muscle
The carotid pulse simultaneous with ventricular systole
Where are the the jugular veins?
Internal jugular veins located deep and medial to the sternomastoid muscle on each side
External jugular veins are more superficial, lateral to the sternomastoid muscle, above the clavicle and typically visible when the patient is supine and flat
What does orthopnea mean?
SOB that occurs while lying flat and is relieved by sitting or standing.
Where is the apical pulse?
Left midclavicular line at the 4th or 5th intercostal space.
