Neuro Pharmacology Flashcards
Describe the affects of inhaled anesthetics on CMRO2, CBF and ICP
decrease CMRO2
increase CBF and increase ICP
What VA does not follow typically affects on CMRO, CBF and ICP?
nitrous oxide
Describe the affects of IV anesthetics on CMRO2, CBF and ICP
Decrease CMRO2
Decrease CBF
Decrease ICP
Describe the affects of local anesthetics on CMRO2, CBF and ICP
decrease CMRO2
Decrease in CBF
Decrease in ICP
Describe the affects of ketamine on CMRO2, CBF and ICP
+/- CMRO2
increase CBF
increase ICP
Describe the affects of opioids on CMRO2, CBF and ICP
+/- CMRO2
+/- CBF
+/- ICP
The effects of vasoactive drugs on cerebral physiology are dependent on
basal BP (+/- 20% of patients baseline)
Magnitude of drug induced change in BP
status of autoregulation
status of the BBB
How much more soluble is nitrous oxide more soluble in the blood then nitrogen?
34x
What are the physiological affects of nitrous oxide?
increase in CBF
Increase in CBV
Increase in ICP
(more dramatic if sole agent)
Unsure of CMRO2 affects
What are the affects of N2O influenced by?
other agents and changes in CO2 tension
How much does an ICP increase with an intracranial tumor with 66% N20?
increased from an avg ICP of 13mmHg to 40mmHg
Alpha 1 agonist affect on CBF and CMRO
no effect
possible decrease in CBF
Alpha 2 agonist affect on CMF and CMRO
decreased CBF and CMRO
Beta agonist affect on CMF and CMRO
increase CBF and CMRO
Beta agonist (with BBB open) affect on CMF and CMRO
BIG increase in CBF and CMRO
Dopamine affect on CMF and CMRO
Increase in CBF
no effect on CMRO
High doses of dopamine affect on CMF and CMRO
decrease in CBF
no affect on CMRO?
Fenoldopam affect on CMF and CMRO
decrease in CBF
no effect on CMRO
Norepinephrine affect on CMF and CMRO
decrease no affect on CBF
increase, no affect on CMRO
Norepinephrine (open BBB) affect on CMF and CMRO
increase CMRO and CBF
Epinephrine affect on CMF and CMRO
increase in CBF an CMRO
Epinephrine (open BBB) affect on CMF and CMRO
increase in CBF and CMRO
Describe the affect of a bolus of an alpha 1 agonist
may transiently (2-5minutes) change CBF & cerebral SaO2
Describe the affect of a continuous gtt of an alpha 1 agonist
little effect CBF & cerebral SaO2
Describe the overall affect of alpha 1 agonist on the brain
maintenance of CPP with these vasopressors
does not have an adverse affe
Alpha2 agonist cause
decrease in CBF (25-30%)
results from reduced CMRO2 leading to reduced CBF
Where are alpha 2 agonists found and what do they modulate?
found in brain and periphery
modulate sympathetic outflow
Where are alpha 1 receptors found?
post-synaptic alpha receptors on vascular smooth muscle
determine arteriolar resistance and venous capacitance (BP)
Alpha 1 agonist
phenylepherine
norepinephrine
Alpha 2 agonist
clonidine
precedex
Beta agonist examples
epinephrine
what do small doses of beta agonist cause?
little effect on CBF