March 27 - Odds and Ends Flashcards
Hypogastric nerve
Carries sympathetic fibers from T10 to T12. Responsible for emission prior to ejaculation
Pelvic splanchnic nerves
Carry parasympathetic fibers from S2 to S4. Responsible for bladder, motility in rectum and sigmoid colon, erection
Innervation of ear
Cervical spinal cord gives off great auricular n and lesser occipital n which provide sensory to external ear.
V3 of trigeminal gives off auriculotemporal nerve which provides sensory to external auditory canal and external tympanic membrane
CNX supplies posterior part of external auditory canal. Stimulation can cause vasovagal syncope
CNVII provides motor innervation to stapedius
CNVIII provides hearing and vestibular proprioception
Liver pathology in alpha1 antitrypsin def
Polymeraized AAT accumulates in hepatocytes. Stains with PAS and resists digestion by diastase
Embryology of cleft lip and palate
Lip and palate form in 5th to 6th week. Cleft lip is failure of one of the maxillary prominences to fuse with the intermaxillary segment. Cleft palate is failure of palatine shelves to fuse with one another or with primary palate.
Cricothyrotomy
Go through skin, superficial and deep cervical fascia, platysma muscle, and cricothyroid membrane. Do not go through cartilages
Anatomy of orbit and imprlications during trauma
Bounded:
- superiorly by thick frontal bone
- laterally by thick sphenoid bone
- inferiorly by thin bone that borders maxillary sinus
- medially by thin bone that borders ethmoid air clels
Trauma most frequently fractures inferior or medial orbit which have thinnest bone. Thus, orbital contencts can herniate down into maxillary sinus or medially into ethmoid air cells
Rat poison
Contains “superwarfarin” - causes mucosal bleeding and ecchymoses
Treat with FFP
How to reduce wrong site surgeries
Independent verification of patient, procedure, and site by two different people
Causes of vertigo: Meniere disease vs benign positional vertigo vs vestibular neuritis
Meniere
- caused by increased endolymph volume/pressure
- recurrent vertigo + unilateral hearing loss/tinnitus
Benign positional vertigo
- otoliths in semicircular canals
- triggered by head movement; no auditory symptoms
Vestibular neuritits
- vestibular nerve inflammation
- single episode lasting days
- no hearing loss
Noise induced hearing loss
High frequency hearing loss. Trauma to sterocilia cells in organ of corti
Tympanic membrane damage
Occurs due to infection, trauma, pressure changes, sudden loud noises. Conductive hearing loss
Lithium toxicity
Presentation: GI, ataxia, tremors, confusion
Causes: coadministration with thiazides, ACE-Is or NSAIDs that impair renal clearance. Lithium similar to Na+ and is reabsorbed in prox tubules of kidney. Thiazides cause mild dehdration, increasig reabsorption of Na+ and lithium in prox tubules
ARDS pathogenesis
Primary causes are pulmonary infection and sepsis. In sepsis, inflammatory mediators travel back to heart and first capillary bed they get pumped to is pulmonary, where they can interact with endothelial cells and cause damage.
Results in capillary leak which leads to pulmonary edema and V/Q mismatch/shunting
Inflammation damages type II pneumocytes, decreasing surfactant production and thus decreasing compliance leading to a stiff and difficult to ventilate lung
Scarring decreases diffusion capacity leading to hypoxia
Fibrin deposition causes permanent thickening of alveolar capillary membrane which decreases diffusion capacity and compliance long term
Acute respiratory failure lasts a few days but fibrosis can cause chronic lung disease
Nitroprusside
Parenteral vasodilator used for hypertensive emeregency. MEtabolized to NO and cyanide ions. Thus, at high doses, cyanide toxicity can be seen
Treatment of cyanide posioning- three options
- Sodium nitrite: increases methemoglobin
- Sodium thiosulfate: sulfer donor, increases conversion to excretable metabolite
- Hydroxycobalamin: cobalt binds CN- ions
Leg compartments
Anterior compartment: deep peroneal nerve, anterior tibial artery and vein
Lateral compartment: superficial peroneal nerve
Posterior compartment: tibial nerve, peroneal artery and nerve, posterior tibial artery and vein
Epistaxis anatomy
Most commonly anterior from Kiesselbach plexus in nasal septum.
Milrinone
PDE3 inhibitor used as an inotrope in HF. Increases cAMP in cardiac myocytes. Also causes systemic vasodilation- both arterial and venous
HAART side effect
Fat redistribution from periphery to central
Thiazolinedione MOA
Go to nucleus and activate PPAR gamma. PPAR gamma increases insulin sensitivity
Hereditary orotic aciduria
AR disorder of de novo pyrimidine synthesis
Presents with: physical and mental retardation, megaloblastic anemia, increaesd urine orotic acid.
Distinguished from ornithing transcarbamylase def by lack of hyperammonemia.
Treat by suppementing uridine which bypasses defective enzyme
Ornithine transcarbamylase deficiency
Urea cycle disorder in which carbamoyl phosphate builds up and is converted to orotic acid resulting in high urine orotic acid.
Ammonia increases resulting in encephalopathy
Hydroxyurea MOA and USe
MOA: inhibitis ribonucleotide reductase
Use: polycythemia vera and essential thrombocytopenia to decrease red cell production. Sickle cell disease to increase fetal hemoglobin
5-fluorouracil MOA
mimics uracil structure. Inhibits thymidylate synthase
Glycerol kinase
Enzyme that converts glycerol to glycerol-3-phosphate which can go to gluconeogenesis or to glycolysis
Acetyl coA carboxylate
Converts acetyl coA to malonyl coA in fatty acid synthesis
Cholestyramine
Binds to bile acids in GI tract, inhibiting enterohepatic recirculation. Increases trigs as side effect
Antithyroid med side effects and MOA
Both: agranulocytosis
Methimazole: teratogenic
PTU: hepatic failure
MOA: inhibits thyroid peroxidase, impairing iodine organification. PTU also decreases T4 to T3 conversion and so is preferred in thyroid storm
Neurophysin
Carrier protein for oxytocin and ADH. PRoduced by the hypothalamic nuclei
Meglitinidines
Similar MOA to sulfonylureas - closes ATP-dependent K+ channels and increases insulin release. Short half life makes it good for controlling post-prandial hyperglycemia
TZD side effects
Fluid retention causing weight gain, edema, and worsened CHF. Also can cause adipose weight gain
Modafanil
Non-amphetamine stimulant used to treat narcolepsy
Metyrapone stimulation test
Metyrapone inhibits cortisol synthesis by blocking 11-beta hydroxylase. Look for ACTH production and increased 17-OH in the urine (can’t be converted to cortisol so builds up)
Ethanol and hypoglycemia
Ethanol increases NADH/NAD+ ratio: inhibits gluconeogenesis but not glycogenolysis (can maintain glucose initially after a binge but then goes down)
Perchlorate
Inhibits Na+-I- symporter responsible for iodine uptake in thyroid gland
Acromegaly presentation
Glucose intolerance Coarsened facial features Joint pain Increased hand and foot size Macroglossia which can lead to OSA
First generation sulfonylureas
Chlorpromide and tolbutamide. Can cause disulfiram like reaction
Lower extremity lymphatic drainage
Medial leg drains superficially, following veins to superomedial and superolateral nodes.
Lateral leg drains deep, following arteries to popliteal nodes and then deep inguinal nodes
Latissimus dorsi
Extends from the iliac crest to spinous processes and attaches to humerus. Innervated by thoracodorsal nerve. Extends, adducts, and internally rorates arm
Trapezius
Muscle in upper back and neck. Elevates, rotates, and stabilizes scapula. Innervated by CNXI
Succinylcholine: MOA and ADRs
Depolarizing NMJ blocker. Works in two phases. In phase I, it depolarizes the membrane, holding the channel open. In phase II it gets repolarized but is still unresponsive to ACh.
Opens the nACHR channel which is a non-selective cation channel, so K+ can exit and cause hyperkalemia and arrhythmia. Can cause malignant hyperthremia. Can aaffect symp or parasymp systems leading to increase or decrease in HR.
Non-depolarizing NMJ blockers
-curium. Antagonize ACh at nicotinic receptor. Side effects include histamine release and anticholinergic activity
Baclofen
Muscle relaxant. Acts at spinal cord GABA receptors
Polymyalgia rheumatica
Seen in 50% of those with temporal arteritis. Achy shoulder and hip girdle pain
Ulnar nerve injury - locations
Most common is funny bone. Can also be caused by damage in Guyon’s canal between hook of hamate and pisiform
COX enzymes
COX-1: housekeeping
COX-2: induced by inflammation
Colchicine MOA
inhibits MT formation, impairing PMN mitosis and chemotaxis
Deep brachial artery
Also called profunda brachii. Branches from brachial artery and travels with radial nerve. Also can be injured with midshaft fracture
Thoracic outlet syndrome
Thoracic outlet is space between first rib and clavicle. Lower trunk comppression results in arm numbness/tingling/weakness. Subclavian vein compression results in upper extremity swelling. Subclavian artery comppression causes exertional arm pain. Most often occurs in scalene triangle.
ACL and PCL
PCL: posterior intercondylar tibia to anterolateral medial condyle of femur
ACL: anterior intercondylar tibia to posteromedial lateral condyle of femur
Blood supply to head of femur
Medial circumflex artery
Cyclophosphamide
alkylating agent. Forms DNA crosslinks, interfering with replication
MLF lesion
Results in decreased adduction of ipsilateral eye
Clotting factor with shortest half life
Factor VII
Vital capacity
Max air you can exhale = TV + IRV + ERV
pleural pressure
Always negative; gets more negative with inspiration. Alveoli go back and forth between pos during inspiration and neg during expiration
Things leaving diaphragm
T8: IVC
T10: esophagus, vagus nerve
T12: aorta, thoracic duct, azygous vein
Pulmonary artery anatomy
R ant to R bronchus
L sup to L bronchus
Lung compliance: what makes go up and down
Increased: emphysema, aging
Decreased: pneumonia, pulmonary edema, pulmonary fibrosis
Causes of crackles
Airways open after collapse. Edema, fibrosis, pneumonia
Rhonchi
Caused by secretion in large airways. COPD
Bronchophony and egophany
Heard in effusion and pneumonia
Fremetius
Increased in pneumonia
Decreased in most other things
