Shock Flashcards
shock
hypoperfusion of vital organs
- not defined as low BP but it can have low BP as a consequence
What is shock all about?
OXYGEN!
O2 consumption > O2 delivery
Lack of O2 causes…..
anaerobic metabolism
- lactic acid production is marker of severity
Autonomic responses to anaerobic metabolism
Arteriolar vasoconstriction Increased HR and contractility Venous constriction Release of norepi and epi Release of ADH to conserve water and sodium
Typical findings in shock
Hyperkalemia Hyponatremia Metabolic acidosis Hyperglycemia Lactic acidosis
Tissue perfusion
MAP = CO x TPR
- drastically affecting CO or TPR can precipitate shock!
SIRS
systemic inflammatory response syndrome AT LEAST 2 of the following: - Temp < 36 or >38 - Pulse >90 - Respirations >20 - PaCO2 < 32 mmHg - WBC 12000 Can think of it like sepsis without the bug!
Classic Clinical Findings in Shock
Hypotension - don’t HAVE to have, but usually present (<20 cc/hr
Metabolic acidosis
Shock Index
= HR/Systolic pressure
normal is 0.5-0.7
Capillary wedge pressure
measures left ventricular pressure
Cardiogenic shock
decreased CO due to pathology of heart
Distributive Shock
initial increased CO –> then falls
decreased SVR, septic shock, spinal cord injury, anaphylaxis
Extracardiac shock
causes decreased CO due to external pathology
ex. PE, tamponade, constrictive pericarditis
Hypovolemic shock
causes decreased CO due to decreased preload
ex. diarrhea, vomitting, hemorrhage, burns
Treatment of shock?
FLUIDS!!!!! (volume replacement)
- vasopressor agents (not incredibly useful)
