B&B Test 2 Flashcards
What is special about alpha-2 receptors?
They are presynaptic autoreceptors
What effect do parasympathetics have on most blood vessels?
None
exception: M receptors on endothelial cells–>NO release–> vasodilation
What is generally under sympathetic control? (at rest) (2 things)
Sweat glands and arterioles
How can we increase outflow of aqueous humor?
alpha agonist or muscarinic agonist
How can we decrease secretion of aqueous humor?
Beta blocker
What is the principle CNS integration center for the ANS?
Hypothalamus
What does the anterior hypothalamus control as far as PNS goes? Posterior?
Anterior- Cholinergic (sweat glands + PS)
Posterior- Adrenal (sympathetic)
What type of bladder dysfunction with:
1) Cortex/ hypothalamus lesion
2) Between pons and lumbar SC
3) Sacral SC or cauda equina
1) Infantile (uninhibited) bladder
2) UMN- spastic bladder with hyperreflexia, no voluntary control, cystitis due to incomplete empty
3) LMN- flaccid bladder, arreflexic, severe retention that can cause renal damage
Where is COX-1 expressed?
Almost all cells
Where is COX-2 expressed
Only expressed in inflammation
What does aspirin decrease? What type of cells produce it?
TXA2, Platelets
Equilibration time definition
Time at which the alveolar concentration equals the inhaled concentration
How do inhaled anesthetics probably work?
Ligand gated ion channels (probably GABA?)
MAC definition
Equilibrium concentration required to prevent movement to skin incision at 1 ATM in 50% of patients
What do NMBDs cause? What do they not cause?
Cause paralysis, not anesthesia
What subunits of nicotinic receptors bind ACh
Only alpha subunits
What is the only used depolarizing muscle relaxant?
Succinylcholine
What receptors does succinylcholine stimulate?
ALL ACh receptors
Who do we not use Sch in? How is it broken down?
Pediatrics (undiagnosed myopathies, hyperkalemia)
Pseudocholinesterase in plasma
- curium (suffix)
- curonium (suffix)
Benzylisoquinolines
Steroidal
(Both non-depolarizing NMDB)
What reverses non-depolarizing NMDBs? What do we give with it and why?
AChE inhibitors (neostigmine) WE give atropine or glycopyrollate to avoid muscarinic side effects
What causes the termination of effects in most IV anesthetics?
Distribution (as opposed to metabolism and elimination)
What IV anesthetic is best at protecting the brain from hypoxic/ischemic damage?
Thiopental (barbituate)
What are the best amnestic agents?
Benzodiazepines
What are opiods good at? What are they bad at?
Opiods are analgesics with some hypnotic action, but are not good for amnesia
What is the shortest acting opiod? What is significant about it?
Remfentanil, it is terminated by elimination
What can remfentanil cause?
Acute tolerance to other opiods
What is the mechanism of ketamine? What is it good at?
Non-competitive NMDA antagonist that is very good at analgesia (relatively complete anesthetic agent)
What drug is best when hemodynamic stability is a must?
Etomidate
What is the mechanism of dexmedetomidine?
Alpha-2 agonist
What is the most common cause of acute liver failure in the US?
Acetominophen toxicity
What is the basis of acetaminophen toxicity?
Liver metabolism (NAPQI formed when p450 metabolizes it)
What must you do as pretreatment for NAC?
Antihistamines and steroids to prevent anaphylaxis
How do you decide who to treat for acetaminophen toxicity? What is it and what are its limitations?
Rumack Nomogram (APAP vs. Time graph) Limitations include limited to single ingestions within 24 hours of OD and doesn't account for inducing drugs
What does use dependent block describe?
Local anesthetics preferably working on active nerves
What does the duration of local anesthetics depend on?
potency and lipid solubility
List the absorption spectrum for local anesthetics of the following:
Brachial plexus, Epidural, IV, Intercostal, Paracervical, Sciatic, subcutaneous, tracheal
IV>tracheal>Intercostal>paracervical>epidural>brachial plexus> sciatic> subcutaneous
What helps that action of LAs by decreasing absorption and increasing neural uptake?
Vasoconstrictors