Adams- Shock Flashcards
What is shock?
Hypoperfusion of vital organs (brain, heart, kidney, lungs, gut)
What proportion of patients diagnosed with shock will die?
1/2
Is shock associated with low BP?
NO
BP can be normal if systemic vascular resistance is elevated and you still have end organ damage (hypoperfusion to organs)
What causes shock?
Oxygen consumption > delivered oxygen
What decreases oxygen?
- Displacement of 02
- Decreased carrying capacity (Hb)
- Decreased pulmonary function
- Decreased blood flow
What decreases oxygen consumption of O2?
- Work of breathing
- Fever
- Infection
What decreases the oxygen that is delivered?
- Hypoxia
- Anemia
- Hypovolemia
- Decreased CO
What happens on a biochemical level if there is not enough oxygen?
Anaerobic metabolism
What is a marker of the severity of oxygen supply/demand balance?
Lactic acidosis
*Follow lactic acid to track course of illness/treatment effectiveness
What are autonomic responses to anaerobic metabolism?
- Arteriolar vasoconstrcition
- Increase HR and contractility (HR falls over time)
- Venous constriction
- Release of Epi, DA, NE, Cortisol
- Release of ADH to conserve water and Na
How do you cells respond to O2 imbalance?
Atp depletion> ion pump dysfunction> influx of Na and loss of Na> cellular edema> lysosomal enzyme release> cell death
What are common findings in someone with shock?
- Hyperkalemia
- Hyponatremia
- Metabolic acidosis
- Hyperglycemia
- Lactic acidosis
**all d/t loss of cell integrity
What is the continuum of shock?
Concern>
SIRS (systemic inflammatory response syndrome>
MODS (multi organ dysfunction syndrome)>
death
What is SIRS?
A septic like disorder in the ABSENCE of infection
Sepsis or SIRS can progress to MODS
How do you diagnose SIRS?
At least two of the following sxs:
- Temp 38
- Pulse > 90 tachycardia
- Respirations >20
- PaCO2 < 4000 or > 12000 or 10% bands
- WBC 12000
*Infection w/out a bug
What happens if there’s a huge fall in CO or SVR?
Cardiac shock and inadequate tissue perfusion
What are the 4 clinical phases of SIRS?
- Increased V requirements, mild respiratory alkalosis + (oliguria, hyperglycemia, increased insulin requirements)
- Tachypneic, hypocapnic, hypoxemic. Moderate liver dysfunction and possible hematologic abnormalities.
- Develops shock with azotemia and acid-base disturbances. Significant coagulation abnormalities.
- Vasopressor dependent and oliguric or anuric. Ischemic colitis and lactic acidosis follow.
A pt shows up with hypotension, cool, clammy skin, and altered mental status, what’s wrong with them?
Shock!
These are the classical findings.
Urine output <20 cc/hr
What causes cool, clammy skin?
High output shock with decreased SVR
**Distributive/dissociative can have uniquely WARMm skin
What are the two most important things to monitor with shock?
Level of alertness
Urine output
What is the shock index?
Heart rate divided by systolic pressure
What is a normal shock index?
s. 5-.7; an index >1 has increased mortality
* Index is inversely related to effective left ventricular stroke work
What is capillary wedge pressure? What is the problem with Swan Ganz?
The holy grail of physiology! The Swan Ganz catheter tells you what’s happening in the LV.
People who had SG died more often.
*Best tool to see what’s happening in the LV if you have healthy lungs
What are the 4 major types of shock?
- Cardiogenic (heart fails- usually MI/valvular disease))
- Distributive/Dissociative (increased area for blood to disperse to-more volume to fill then you have CO to fill it with)
- Extracardiac (outflow obstruction- PE)
- Hypovolemic (lack of fluid)
