Critical Care Flashcards
What is the first step in resuscitation of a drowning victim?
rescue breathing
How should CVLs placed under emergency conditions be managed?
replaced within 24 hours at a new site
Why is propofol infusion syndrome associated with lactic acidosis?
propofol prevents mitochondria from using fatty acids as an energy source, so after glucose and amino acids stores are used up, lactic acidosis develops
What is the equation for arterial oxygen content?
CaO2 = (1.34 x Hgb x SaO2) + (0.003 x PaO2)
What is the equation for oxygen delivery?
DO2 = CaO2 x CO
What is the equation for oxygen consumption?
VO2 = 1.34 x (SaO2 - SmvO2) x Hgb x CO
OR
SmvO2 = SaO2 - [VO2/(1.34 x Hgb x CO)]
What is the oxygen extraction ratio?
ER = VO2/DO2
What is the alveolar gas equation?
PAO2 = FiO2(Patm - PH2O) - PaCO2/RQ
Patm = 760 mmHg
PH2O = 47 mmHg
RQ = 0.8
What factors affect the Hgb dissociation curve?
What is a normal value for VO2?
250 mL/min
What is dysoxia?
When oxygen consumption (VO2) decreases because oxygen delivery (DO2) is so low (i.e., no more oxygen can be extracted from what is delivered)
What is the Bohr effect?
Increased CO2 binding to Hgb reduces its affinity for O2 (i.e., a right shift in the hgb dissociation curve)
What is the Haldane effect?
oxygenated Hgb has a lower affinity for CO2 (facilitating CO2 unloading in the lungs)
deoxygenated Hgb has a higher affinity for CO2 and can act as a buffer
What is the law of LaPlace?
pressure = 2 x wall tension x wall thickness/radius
How is the majority of CO2 carried in the blood?
as bicarbonate in the plasma and RBCs