W9 D3-4 - Shock Flashcards
What are 3 main signs of shock?
Low BP, Low CO, hypoxia
Summarize the phases of shock
Initial
How much blood must be lost during hypovolemic shock?
20% of their total volume
What defines cardiogenic shock?
Heart pump problem
* inefficient contractility
* coronary / non-coronary
* decreases FOC, CO, tissue perfusion
Coronary vs non-coronary cardiogenic shock
Coronary
* most common
* MI, cell death
Non-coronary
* myocardial dysfunction, myocarditis
What are the 3 main coronary arteries?
Circumflex
RCA
LAD
What are the 3 possible types of dysfunction in cardiogenic shock?
LV systolic dysfunction - impaired contractility
LV diastolic dysfunction - impaired filling
Right ventricular failure - LVfailure, increased pulmonary afterload
What are the goals of treatment for cardiogenic shock?
LVF
* improve pump function - dobutamine / milrinone
* tissue perfusion - restore MAP
* prevent pulmonary edema - ventilated
RVF - hard to treat
* increase RV pump function - optimize preload
* improve forward flow of blood
VVV
Pharmacological agents
* inotropes to increase FOC; dobutamine, milrinone, epinephrine
* pulmonary vasodilators to V pulmonary hypertension
What is an intra aortic balloon pump? IABP
Compare shocks
Hypovolemia - low volume
Cardiogenic - pump problem
Disruptive - vasodilation
Explain neurogenic shock
SNS is suppressed causing vasodilation
On its own, PSNS decreases in HR
often caused by spinal cord injuries
What can cause neurogenic shock? How?
Total Injuries above T6 causes a loss of sympathetic tone in the blood vessels (chronic issue)
* pacemaker needed
Spinal cord cervical and thoracic edema above T6 causes as TEMPORARY loss of SNS innervation to blood vessels
Vasomotor center dysfunctions
* from compression via ^ ICP, herniation, barbiturates
* messages cannot be sent down to the muscles
What happens with a loss of SNS tone? in neurogenic shock
1. Decreased CO
2. Decreased tissue perfusion
Cause by…
* bradycardia
* peripheral vasodilation = arterial vasodilation (= V afterload) & = venous vasodilation (= V preload) = V BP
* impaired thermoregulation = room temp
What are the goals of treatment for neurogenic shock?
1. Prevent cardiovascular instability
* fluid resus.
* vasoconstrictor: norepinephrine
* atropine, dopamine, epi, pacing
2. Prevent CNS instability
* spinal cord injury care, log roll
* caution with suctioning, vagal nerve stimulation, have atropine
3. Improve tissue perfusion
* caution turning, watch hypo/hypertension as no SNS compensation
* atropine
4. Maintain normothermia
* warming/cooling blanket
* prevent DVT d/t vasodilation
* anticoagulation, compression device
Explain the patho of anaphalactic shock
Histamine is released from mast cells
1. histamine 1 receptors
* vasodilation leaky capillaries
* smooth muscle constriction
* both cause respiratory constriction & cardiovascular decrease (BP, SVR, preload) tachycardia = decreased CO and tissue perfusion
* skin: rashes, hives, itchy
2. histamine 2 receptors
* increase in stomach acid
* causes vomiting, cramping, abdominal pain
Treatment goals for anaphalactic shock
Define septic shock
Systemic inflammatory response syndrome (SIRS) (to tissue injury)
* temperature high or low
* HR above 90
* RR above 20
* WBC above 12000, less than 4000
Sepsis:
* organ dysfunction d/t dysregulation response to infection
Progressing to shock
* profound circulatory, cellular, metabolic abnormalities including hypotension, serum lactate above 2
Explain the patho of septic shock
Too many or not enough inflammatory mediators
1. ^ inflammation
2. ^ coagulation
3. V fibrinolytic activity / V clot breakdown
4. high metabolic rate (febrile)
What are the goals of treatment for septic shock?
1 hour bundle - initiate uprecognition of sepsis
1. Lactate level
2. Obtain blood cultures
3. Administer broad spectrum antibiotics (piptazo, vanco)
4. Rapid admin of 30 mL/kg crystalloid (NS/ringers) for hypotension / lactate above 4
5. Vasopressors to maintain MAP > 65
