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
Result if LA is injected directly into muscle?
Myotoxicity
Eating nonfood, non-nutritional substances (ex. ice, chalk)
Pica
Repeated regurgitation of food not due to a medical problem
Rumination disorder
Lack of interest in food
Avoidant food intake
Intense fear of gaining weight and behavior that causes it. Can be associated with amenorrhea, lanugo hair, and keratitis
Anorexia Nervosa
Binge-Purge-Binge-Purge-Binge-Purge
Bulimia Nervosa
What are symptoms of bulimia?
more cavities, acid reflux, Russel’s sign, enlarged salivary glands
Lack of control of eating large quantities of food
Binge eating disorder
What are complications of AN and BN caused by?
AN- Starvation and weight loss
BN- Frequency and type of purging
Cardiac complications of AN and BN
AN: Bradycardia, hypotension, atrophy
BN: Normal HR, arrhythmias secondary to electrolyte imbalances
What are two big hints for AN? What is the electrolyte status?
Osteoporosis and amenorrhea with normal electrolyte levels
Hypokalemia in young, healthy women is a very specific sign for what?
Bulimia Nervosa
Lateralized pain that is dull and deep, aura, photo/phonophobia?
Migraine
How do we treat migraines? Prevention?
Treat with excedrin or triptans
Prevent with Calcium blockers, beta blockers or TCA
Repetitive headache with times of remission described as sharp, stabbing pain. Ipsilateral pain and horner’s like problems, yet patients choose to stay active
Cluster headaches
How do we treat cluster headaches?
100% oxygen
What is the DOC for tension headaches?
NSAIDs
What do you suspect with visual loss, weight loss, jaw/arm claudication? What do you do?
Temporal arteritis. Temporal artery biopsy, start steroids
What age group is susceptible to temporal arteritis?
> 50
Otoliths into semicircular canal
Benign positional vertigo
Describe the path of the vestibule-ocular reflex.
Vestibular nucleus–> CN6–> MLF–> CN 3,4
How does the direction of endolymph flow relate to tracking direction, nystagmus direction?
Tracking direction is the same, nystagmus direction is the opposite
What can compress CN7 and CN8 and where?
Acoustic neuroma (schwannoma) in the internal auditory meatus
When is ADHD diagnosed? More males or females?
School-age, more males
What is the strongest evidence for the cause of ADHD?
NE neurons in locus coeruleus
How many sx must be present in people up to 16? After?
6, 5
What are the four required characteristics of ADHD?
1) Sx before age 12
2) Interfere with functioning
3) Occur in more than one setting
4) Does not only occur with other disorders
What would you suspect if a child with ADHD becomes irritable or hyperactive all of the sudden?
rebound effect as the drugs are wearing off
How much louder in decibels is a sound that is 10x louder? 100x?
db=20log(x)
10x= 20
100x=40
How does a low force sound wave on the tympanic membrane cause a large enough force on the oval window?
Impedence matching
What are the two muscles that protect from hyperacusis? What innervation?
1) Stapedius- CN7
2) Tensor Tympani- CN5
What would you suspect with a patient that has ear pain with changes in pressure such as flying or scuba diving?
Perilymph fistula (leakage)
What two distinguishing factors will you see on brain sections of a patient with prions?
1) Amyloid plaques
2) Spongiform changes and neuron loss
How can prion be transmitted?
Sporadic, mutations, ingestion or inoculation of contaminated material
How do you diagnose Prion disease?
Western blot of tonsil biopsy, brain biopsy
Viral encephalitis characterized by hydrophobia
Rabies
What would you suspect with Negri bodies?
Rabies
What is another way to diagnose rabies besides brain biopsy?
DFA- Direct fluorescent antibody with the nape of the neck
How do we treat rabies?
Rabies Ig, Post-exposure vaccination
What four families of virus fit in arbovirus? Exceptions?
1) Togavirus (rubella)
2) Flavivirus
3) Bunyavirus (not hantavirus)
4) Reovirus (not rotavirus)
What causes the sudden fever associated with arboviruses?
RNA viruses elicit a massive IFN response
Are arboviruses enveloped or non enveloped. Exception?
Enveloped with the exception of Colorado Tick Fever
Subgenomic RNA
Togavirus
Polyprotein
Flavivirus
Transovarial Transmission
Bunyavirus
Segmented, negative-sense RNA
Bunyavirus
Are arboviruses seasonal?
Yes, summer and early fall
What do you do upon suspicion of viral encephalitis?
Give acyclovir (in case it is herpes)
Will you always see virus in the blood?
No, viremia is transient and only at the early stages of the disease
What is the most important arboviral concern to human health?
Dengue Virus
When should you suspect Dengue? Diagnostic test?
Anyone with fever who has travelled to the tropics. Tourniquet test
What is the significance of multiple serotypes of Dengue? How many?
5 serotypes and it is thought that reinfection leads to more severe disease
Why would reinfection lead to more severe disease with Dengue?
Antibody-Dependednt Enhancement, antibodies that do not neutralize virus just mark it for dendritic cell and macrophage uptake, which is the target of the virus anyway.
How do we treat Dengue?
We have no treatment. Mosquito eradication
How do we treat tetanus?
Tetanus booster, DEBRIDEMENT, Toxin Ig, antibiotic
Compare the mortality of infant tetanus and botulism.
Tetanus ~90%
Botulism ~1-2%
What type of nerve infection do we often see in botulism?
Cranial Nerves!!!!
How do we treat botulism?
HBAT (equine heptavalent botulism anti toxin) ALWAYS CHECK FOR ALLERGIES
