What corresponds with the electrical R wave on an ECG?
Mitral valve closure
What happens to the FRC when you age? With height changes?
It increases. This is due to the elastic recoil of the lung decreasing. FRC will increase with height
What effect does propofol have on SSEPs?
Decreases amplitude and increases latency (not to the extent that volatiles or barbiturates will)
What is the standard FRC in a standard adult patient? What is the oxygen consumption?
FRC: 30 ml/kg
O2 consumption: 3-4 ml/kg/min
Name 3 hormones that are metabolized in the pulmonary circulation
What is the posterior pituitary gland called?
The neurohypophysis (this releases oxytocin and ADH)
Which is more active? T3 or T4? Why? How is T3 formed?
T3 due to decreased protein binding. It is formed by the peripheral conversion of T4 to T3 by 5-iodinase
What neuro monitoring system is MOST affected by volatiles?
Visual: VERY #1
Motor: most
Somatosensory: somewhat
Brainstem auditory: barely
What ratio of urine osmolarity to plasma osmolarity indicates a pre-renal cause of oliguria?
Uosm: Posm > 1.5
Urine osmolarity > 440 and Plasma osmolarity > 285
What effects do a L to R shunt and a R to L shunt have on inhalational induction and IV induction?
What are the three main ways that CO2 is carried in the blood?
Name 6 factors that increase MAC
Things that increase cerebral metabolic rate:
Which vertebral segments house the SNS?
T1-L3
What ganglia are part of the UE SNS?
upper cervical, middle cervical, and stellate ganglia (stellate is the fusion of the lower cervical and first thoracic ganglia)
What is the reticular activating system?
The part of the brain that alters consciousness. Signals are transported from the RAS via the thalamus to the cerebral cortex. Most anesthetics (except Ketamine) directly depress the RAS. Ketamine works on the Thalamus
Explain the changes seen with pregnancy that occur with spirometry
2. There is a decrease in RV and ERV, meaning that IRV will increase
Name the sleep stages, in order, of awake to asleep
BATS Drink Blood Beta (awake) Alpha (drowsy) Theta (stage 1) Spindles and K complexes (stages 3/4) Blood (awake)
Higher frequency waves start at the top and decrease in frequency as you progress
What determines movement of fluids across the BBB? What common molecule crosses the BBB freely?
Intravascular osmolarity and oncotic forces.
Water crosses the BBB freely
What techniques can be used as an ancillary modem of confirming brain death? What defines electro cerebral silence?
2. EEG < 2uV/mm activity
What is the volume left at the end of normal tidal volume breathing?
FRC (ERV + RV)
Describe the changes seen with altitude sickness. What are the complications? How can you prevent it?
What is the equation for CPP? What does the body do to acutely compensate for increases in ICP?
MAP - (ICP or CVP: depends on which is highest)
Describe the ABG of a pregnant woman
Describe the formation and metabolism of Ach