Exam 1 - States of Shock Flashcards
What is the classic definition for shock? (2)
hypotension as either an SBP <90 mmHg or a decrease in 40 mmHg from baseline
What is the formula for mean arterial pressure?
MAP = 1/3 SBP + 2/3 DBP
List factors affecting MAP? (2)
cardiac output, vascular resistance
List factors affecting cardiac output? (2)
heart rate, stroke volume
List factors affecting stroke volume? (3)
preload, afterload, contractility
What is the goal MAP? HR? Lactate?
MAP >65 mmHg; HR = <100 bpm; lactate <2 mmol/L
What is the goal venous blood gas for pulmonary artery catheters? Central venous catheters?
PA = >60%; CVC = >65%
List the shock states? (4)
hypovolemic, distributive, cardiogenic, obstructive
Define hypovolemic shock and list its causes?
inappropriately low and sudden loss of intravascular volume; hemorrhage, GI losses, severe dehydration, third spacing, burns
Match the clinical parameters associated with physical variables? (4)
preload = PCWP, pump function = CO, afterload = SVR, tissue perfusion = mixed venous oxygen saturation (SVO2)
Explain the changes during hypovolemic shock? (4)
decreased preload, decreased pump function, increased afterload, decreased tissue perfusion
What are treatments for hypovolemic shock? (3)
surgical hemostasis, replace blood (PRBCs, anticoagulation reversal), fluids (IV crystalloids, albumin)
Define cardiogenic shock and list its causes?
failure of left ventricle to deliver blood due to impaired stroke volume or heart rate; MI, arrhythmias, HF, valve diseases, dilated cardiomyopathy
Explain the changes during cardiogenic shock? (4)
increased preload, decreased pump function, increased afterload, decreased tissue perfusion
What are treatments for cardiogenic shock? (3)
revascularization for MI (CABG), correct arrhythmias, left ventricular assist devices (LVADs) and ECMO