Shock Flashcards
blood pressure in systemic arteries will be lower than normal when blood volume in arteries is reduced due to decreased ______ or decreased ______ (increased runoff from arteries to veins)
cardiac output
TPR
diastolic pressure mainly determined by:
- rate of _______, how fast bloods flow from arterial to venous system, determined by TPR
- ______ time, during diastole, determined by heart rate
- arterial _______ pressure, the starting point from which runoff causes pressure to decrease
runoff
runoff
systolic
determinants of arterial systolic pressure:
- _______ rate, determines how quickly blood volume in arterial system increases, which infuences peak systolic pressure attained
- _______: arterial pulse pressure is an index, if volume increase, arterial pulse pressure increases
- _______ compliance, increases cause increase in systolic pressure
- arterial ______ pressure: starting point where pressure begins to increase during ejection
ejection
stroke volume
arterial
diastolic
calculation of MAP?
MAP= diastolic pressure + (1/3) pulse pressure
represents the driving pressure for blood flow in the systemic circulation, the baroreflex response is a negativ feedback system that attempts to maintain it at nearly constant levels
MAP
- stretch on myocardial fibers before contraction
- indices: EDV, EDP, venous return
- related to ventricular filling: determined by heart rate (decreased HR increases filling time, increasing stroke volume)
- rate of venous return: increased venous return increases EDV and increases stroke volume
preload
law that states when preload increases, the stroke volume increases due to stretch which result s in more favorable overlap of thin and thick filaments, more cross bridge formation
Starling’s Law
- the ventricular wall tension during ejection, the resistance that must be overcome to eject blood
- pressure at start of ejection (aortic diastolic pressure) or peak pressure (aortic systolic pressure) are used as indices
- changes in TPR will affect, increased TPR slows rate of runoff which will increase arterial diastolic pressure
afterload
- contractility, dependent on cytosolic calcium level within contracting myocytes
- levels submaximal under normal conditions
- norepi will enhance calcium entry into myocytes
inotropic state
TPR is mainly due to systemic _______ resistance
arteriolar
-constriction of systemic arterioles will increase TPR, decreasing the rate of runoff of blood to from arteries to veins, increasing _______ diastolic pressure, increasing afterload resulting in decreased stroke volume on next beat
arterial
- decreased blood volume resulting in inadequate cardiac output
- skin feels cold and clammy
- low central venous pressure
hypovolemic shock
- generalized systemic vasodilation
- blood volume initially normal
- warm shock, low resistance
distributive shock
- inadequate cardiac output by a diseased or impaired heart
- congested shock due to pump failure
- high central venous pressure
- skin cold and clammy
cardiogenic shock
decreased blood volume -> decreased venous return -> decreased stroke volume -> decreased CO –> decreased arterial pressure
hypovolemic shock
the ____ and ____ exhibit autoregulation, where flow is maintained nearly constant at low arterial pressures by _________ and at high arterial pressures by local ________
arteriolar dilation
arteriolar constriction
- insufficient O2 delivery to the heart relative to O2 consumption
- seen as ST segment shift from normal baseline
- increased consumption: increased inotropic state, afterload, HR, preload, or ventricular hypertrophy
- decreased O2 delivery: decreased coronary bloodflow, decreased arterial O2 levels
myocardial ischemia
- hemorrhagic shock: isotonic fluid (blood) lost, so it’s ______ contraction
- dehydration: more water than salt lost, so ECF osmolality is increased, causes water to move out of cells and ICF volume is decreased, this is a _______ contraction
isotonic
hypertonic
in septic shock, the pro-inflammatory factors outweigh even high levels of ______ and leukocyte adherence to postcapillary venules occurs, resulting in microvascular injury
nitric oxide
- anaphylactic shock involves degranulation of _____ cells in response to allergen
- histamine will increase vascular _______, which will complicate rescucitation
mast
permeability
- neurogenic shock is produced by loss of vascular _____ due to inhibition of normal tonic activity of sympathetic vasoconstrictors
- can be treated with an _______ to constrict systemic arterioles which increase TPR
tone
alpha-1 agonist
- greater than normal decline in systolic arterial pressure during inspiration
- in cardiac tamponade, the increase in venous return to the right ventricle during ______ causes an exaggerated reduction in left ventricular volume
- the increased filling of the right ventricle during inspiration causes the septum to bulge to the left ventricle, decreasing filling and reducing stroke volume
paradoxical pulse
cardiac tamponade causes a ______ ECG recording, where the fluid in the pericardial sac would diminish the magnitude of electrical events recorded on the EKG, heart sounds will be diminished as well
low amplitude
in irreversible shock, impaired organ blood flow will lead to accumulation of _______ metabolites, increasing ______ causing acidosis and impaired cell function
vasodilator
lactic acid
