Shock Flashcards
what is shock?
severe cardiovascular failure caused by poor blood flow or inadequate distribution of flow
what are complications of shock?
organ failure and death unless a cause can be identified
what are the physical responses of shock medicated by?
catecholamines, renin, ADH, glucagon, cortisol, and GH
what is hypovolemic shock?
caused by hemorrhage, loss of plasma, loss of fluid and electrolyes, resulting in decreased intravascular volume
what can cause hypopvolemic shock?
thin 3rd spacing or by obvious loss
what is cardiogenic shock
caused by MI, dysrhythmias, heart failure, defects in the valves or septum, HTN, myocarditis, cardiac contusion, rupture of ventricular septum or cardiomyopathyies
what are causes of obstructive shock?
tensino PTX, pericardial tamponade, obstructive valvuar dz, pulmonary problems including massive PE
distributive shock?
poorly regulated distribution of blood volume
-includes septic shock, systemic inflammatory response syndrome (systemic inflammation w/o end-organ damage)
- anaphylaxis
- neruogenic shock
what ist he most common cause of distributive shock?
septic
what bacteria is most associated with septic shock?
gram negative (ppl of extreme ages)
what other pt population is septic shock found int?
DM or immunosuppression, those that have recently had an invasive procedure
what are causes of neurogenic shock
spinal cord injury, or adverse effects of spinal or epidural anesthesia
what are signs and symptoms of shock?
hypotension, orthostatic changes, tachycardia, peripheral hypoperfusion, AMA, oliguria or anuria, insulin resistance, and metabolic acidioss
what are signs of end-organs hypoperfusion?
cool/mottled extremities, diminished capilarry ref, weak or thready/ or absent peripheral pulses
what type of diagnostic studies can be done?
CBC, blood type and cross matc, coagulation parameters
-CMP, glucose, UA, serm cretinin-aid in dx
tx of shock
depends on specific cause and manifestations
first step of shock tx?
ABCD
what is the trendelenburg postions
get blood back to brain
what should urine flow be at?
0.5 ml/kg/hr
what labs should be done in critically ill patients
central venous pressure, pulmonary arter catheters, capillary wedge pressure monitoring
what meds can be used to tx shock?
inotropes: dobutamine, dopamin, epi
how do inotropes work?
increase CO by increased contractility
what can be used to alter heart rate?
chronotropes: adrenaline (+); dig (-)
what do pressors do?
increase vascular tone
dopamine, phenylephrine
what are the major deerminants of tissue perfusion>
Systemic BP, CO, systemic vascular resistance
what is stroke volume determined by
preload, myocardial contractiliyt, afterloa
what is systemic vascular resistance determined by?
vessel length, blood viscosity, vessel diameter
what does cellular hypoxia cause?
on pump dysfunction, intracellular edema, leakage of intracellular contents into the extracellular space, and inadequate regulation of intracellular pH. These biochemical processes, in turn, progress to acidosis, endothelial dysfunction, and further stimulation of inflammatory and anti-inflammatory cascades.
