Heme/Onc Flashcards

1
Q

Purine Degradation

A

-Purine -> Xanthine or hypoxanthine –> uric acid (xanthine oxidase)

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2
Q

Urate in the Kidney

A
  • Urate is filter, secreted, and reabsorbed
  • reabsorption predominates
  • URAT-1 (OAT)
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3
Q

Causes of Hyperuricemia

A
  • Under excretion due to renal impairment, HTN, low dose aspirin
  • Urate overproduction from purine rich diet, tumor lysis syndrome
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4
Q

TX of asymptomatic Hyperuricemia

A

-Diet modification and weight loss

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5
Q

TX of symptomatic Hyperuricemia

A
  • Diet modification

- Drug therapy to lower risks of recurrent attack, relieve symptoms of acute attack, and reduce serum urate levels

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6
Q

Drug Classes

A
  • Uricostatic agents: reduce formation of uric acid
  • Enzymes: metabolize uric acid
  • Uricosuric Agents: Increase excretion of uric acid by the kidney
  • Anti-inflammatory agents: relieve acute attacks of gout
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7
Q

Allopurinol

A
  • Analog of hypoxanthine acts as competitive inhibitor of xanthine oxidase
  • XO turns allopurinol into oxypurinol which is a non competitive XO inhibitor (longer half life)
  • Dissolution of tophi by lowering serum levels of urate
  • Decreases risk of nephropathy
  • Increase risk of acute attacks due to tissue mobilization of urate (Colchicine given before therapy is started)
  • Probenecid increases clearance of oxypurinol which requires incr. dose, but allopurinol increases the half life of probenecid requires lower dose
  • Mercaptopurine and azathioprine require dose reduction due to inhibition of XO
  • Hypersensitivity RXN (rash fever malaise and myalgias)
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8
Q

Feboxostat

A
  • Non-purine, non-competitive inhibitor of oxidized and reduced form of XO
  • Used as an alternative to allopurinol approved for hyperuricemia with gout attacks
  • Abnormal liver functions, nausea, joint pain and rash
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9
Q

Pegloticase

A
  • Urate oxidase that converts rate to inactive and soluble allantoin
  • Peds tumor lysis syndrome in cases of leukemia, NOT CHRONIC GOUT
  • pegylation increases half life and reduces antigenicity
  • Blood samples for urate levels must be chilled to prevent enzymatic degradation
  • Hemolytic anemia in G6P, anaphylaxis, metheglobinemia
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10
Q

Probenecid

A
  • Decreases reabsorption of urate by inhibiting URAT-1
  • Liberal H20 intake to prevent stones and keep urine pH above 6
  • DONT USE: nephrolithiasis, over production of urate and patients with renal insufficiency
  • Combine with Colchicine to prevent acute attacks
  • GI irritation use caution with patients who have ulcers
  • Salicylates reduce efficacy:
    • Low dose blocks proximal tubule secretion of urate -> hyperuricemia
    • High doses: block secretion and reabsorption w/ increase risk of stones
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11
Q

Losartan

A

-moderate uricosuric option for patients w/ HTN who are intolerant to probenecid

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12
Q

Anti-inflammatory Drugs

A
  • NSAIDS: within 24 hrs of onset for 3-4 days and then taper for 7-10 (aspirin contraindicated)
  • Glucocorticoids: Use if NSAIDs don’t work, intra articular administration effective if 1-2 joints affected
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13
Q

Colchicine

A
  • Anti-inflammatory
  • prevents activation, degranulation, and migration of neutrophils that mediate gout symptoms
  • Enterohepatic recirc, dose reduction in liver and renal insufficiency
  • Uses acute gout, and fixed dose combo with probenecid
  • GI effects are frequent
  • myelosuppression, leucopenia, granulocytopenia, thrombopenia, aplastic anemia
  • Don’t use with 3A4 and P-glycoprotein inhibitors
  • minimum of 3 days between treatments
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14
Q

Indomethacin

A
  • nonselective COX-inhibitor
  • 30-50% experience adverse effects
  • GI effects can be fatal
  • severe frontal headaches
  • Seizures, depression, psychosis, hallucinations, and suicide
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15
Q

Amino Esters

A

Benzocaine cocaine Tetracain Procaine

Ester linkage between lipophilic and hydrophilic ends

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16
Q

Amino Amide

A

Lidocaine, Prilocaine, Meprivacine, Bupivacaine

-Amide linkage between lipophilic and hydrophilic ends

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17
Q

Mechanisms of action for local anesthetics

A
  • Block Na channels along Axons when the channel is open in a voltage and time dependent manner.
  • No loss of consciousness
  • Reversible
  • Ionized form has a higher affinity for the receptor
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18
Q

Local anesthetics crossing the membrane and blocking the receptor

A

-Non-ionized form diffuses across the nerve membranes while the ionized form (with H+ ion) blocks the receptor

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19
Q

Effects of Na+ blockage on nerve conduction

A
  • Threshold for excitation increases
  • Impulse conduction slows
  • Action potential amplitude decreases
  • Eventually ability to generate action potential is completely abolished
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20
Q

Fibers affected by Local anesthetics

A
  • Local anesthetics are more efficacious on nerves that are rapidly firing or chronically depolarized
  • C and B (pain)fibers are blocked first followed by A fibers
  • A-alpha are blocked last (motor and proprioception)
  • Recovery occurs in the reverse order
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21
Q

Potency and Duration of Local anesthetics

A

-Increases in lipophilicity –> increases in duration and potency.

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22
Q

Vasoconstrictors with Local Anesthetics

A

-Used to reduce rate of systemic absorption and prolong duration of action

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23
Q

Most potent and longest lasting amino ester

A

-Tetracaine (procaine shortest and weakest)

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24
Q

Most potent and longest lasting amino amide

A

-Bupivacaine (mepivacaine the worst)

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25
Q

Metabolism of Esters and amides

A
  • Esters: Metabolized in plasma by plasma cholinesterases

- Amides: Metabolized in the liver by cytochrome P450 enzymes

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26
Q

Toxicity of local anesthetics

A
  • Degradation: Hypersensitivity due to formation of benzoic acids and derivatives -> allergic rxns
  • CNS: sedation, visual and auditory disturbances, tongue numbness and metallic taste, Nystagmus and muscular twitching –> tonic-clonic convulsions (depression of inhibitory pathways)
  • Cardio: cardiac conduction and function effects (Bupivacaine)
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27
Q

Transient Nuerological Symptoms

A

-Syndrome of transient pain or dysethesia from spinal or epidural administration

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28
Q

General anesthesia

A

-Reversible CNS state loss of response to and perception of stimuli

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29
Q

Dissociative Sedation

A

-Trance like cataleptic state in which the patient experiences analgesia and amnesia but retains reflexes and CV stability

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30
Q

Inhalation

A

-Continuous inhalation of gas or volatile liquid which rate depth and duration of anesthesia are under control. Recovery occurs when gas is turned off and anesthetic is eliminated by exhalation

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31
Q

Intravenous

A

-Lipophilic and injected, rapid onset, but depth and duration are not well controlled, duration depends on rate of metabolism.

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32
Q

Stages of Anesthesia

A
  1. Conscious but drowsy with variable degrees of analgesia
  2. Excitement and delirum –> unconscious reflex response to pain (during recovery)
  3. Surgical anesthesia regular respiration
  4. medullary depression with loss of respiration and vasomotor control -> death

-Now defined as induction, maintenance and emergence

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33
Q

CV effects of general anesthesia

A

-Decrease mean arterial blood pressure by

vasodil, myo suppression, blunted baroreceptor reflex and decreased sympathetic tone

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34
Q

Respir effects of General anesthesia

A
  • Reduced or eliminated vent. drive
  • Lose gag and cough reflex
  • reduced LES tone
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35
Q

Emergence

A
  • Naseau and vomiting due to tim of CTZ (treat with 5HT3 agonist)
  • Return of sympathetic tone –> Tachy and HTN
  • Shivering treated with meperidine
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36
Q

Mechanism of Action

A

-Reversibly interact with hydrophobic sites of specific membrane receptors (enhance inhibit GABA)

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37
Q

Pharmacokinetics of Inhaled Anesthetics

A

-Achieve equilibrium between alveolar gas and brain tissue: exhaled gas = inhaled gas
which is affected by blood solubility, alveolar blood pressure and partial pressure
-Concentration is expressed as partial pressure (more H2O soluble = lower partial pressure)
-Blood solubility: Lower solubility = higher partial pressure = faster rate of induction

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38
Q

Nitrous Oxide

A
  • Use in dental procedures or in combo to reduce dose of other inhalation agents
  • Advantages: good analgesia and amnesia, minimal CV effects, Reduced side effects of other inhalation agents
  • Disadvantages: Not complete anesthetic, rigidty, Diffusion hypoxia, Pneumothorax, inhibits b12 dependent enzymes so don’t use chronically
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39
Q

Halothane

A
  • Induction/maintenance of anesthesia, still used in US for induction of peds (side effects less pungent)
  • advantages: rapid induction and recovery, muscle relaxant/bronchodilator
  • Disadvantages: Poor analgesic (hangover), significant cardiac depression (decrease MAP and sensitizes heart to epi tachy), Increase ICP, hepatitis
40
Q

Isoflurane

A
  • Use for maintenance at 1-2%
  • Advanatages: good CV profile
  • Disadvantages: pungent
41
Q

Desflurane

A

Widely used for maintenance during outpatient due to fast onset and recovery

  • Advantages: very rapid induction and emgerence, similar CV effects to isoflurane
  • Disadvantages: Pungent -> bronchial irritation cough and salivation
42
Q

Sevoflurane

A
  • Wide use for induction and maintenance in kids

- Advantages: low pungency and good CV profile

43
Q

Malignant hypothermia

A
  • Genetically susceptible patients exposed to halogenated inhalation anesthetics and/or succinylcholine
  • Post-op Hypercatabolic state: (hypercapnia, muscle rigidity, tachycardia, hyperthermia, hyperkalemia, Frequently fatal)
  • Mutation in skeletal muscle dihydropyridine or ryanodine receptors -> excessive intracellular Ca accumulation (severe contractions)
  • Tx: stop trigger, pure O2, skeletal muscle relaxant, and treat hyperkalemia and it’s related effects
44
Q

IV anesthetics

A
  • Used for induction
  • Benzodiazepines used prior to sedation anxiolysis
  • Given IV bolus or by constant infusion
  • Barbituates: Methohexital, thiopental
  • Non-Barbiturates: Propofol, Ketamine, etomidate
45
Q

Methohexital:

A
  • Short acting barbiturates
  • Activates barbiturate binding site on GABA-A receptors
  • Duration 10 min
  • Induction of anesthesia and procedural sedation
46
Q

Propofol

A
  • Most commonly used IV agent in the US
  • GABA-A agonist: sedative and amnestic, non analgesic
  • Duration 6 min
  • General anesthesia induction and maintenance
  • procedural sedation
  • Pst-Op anti emetic
  • Hypotension, respiratory depression, pain at induction site, potential for hypertriglyceridemia (fosopropofol no side effects)
47
Q

Ketamine

A
  • NMDA receptro antagonist (blocks glutamate) -> dissociative sedation, significant analgesia and bronchodilation and minimal CV side effects
  • Unpleasant emergence phenomenon, less prevalent in kids
  • Can be used for procedural analgesia/sedation for brief painful procedures
  • CNS pyschotomimetic: Vivid dreams, hallucinations, distorted visual and auditory sensitivity during emergence associated with fear and confusion, but may also produce euphoria can be counteracted with benzos
48
Q

Causes of muscle spams

A
  • Over stretching of muscle
  • Repetitive strain of Muscle
  • Wrenching of a joint
  • Tearing of tendon or ligament
49
Q

Spasm pain spasm

A
  • Muscle overuse activates nociceptors in muscle which have synaptic connections with alpha and gamma motor neurons
  • increased activity of neurons and increased muscle contraction
  • Force of muscle contractions may compress blood vessels leading to ischemic contraction which excite nociceptors
50
Q

Spasmolytics

A
  • Chlorzoxazone, cyclobenzaprine, methocarbamol, orphenadrine
  • All spasmolytic drugs alleviate the Sx of localized muscle spasms and no one is better than the other while all are equally effective as NSAIDS
  • The difference amongst pain meds is onset and duration of action
51
Q

Onset and duration of Spasmolytics

A

-Carisoprodol and methocarbamol are the quickest while cyclobenzaprine is the longest acting.

52
Q

Mechanism of actions of the spasmolytics

A
  • Depresses polysynaptic reflexes in the spinal cord (over monosynaptic)
  • Cyclobenzaprine reduces tonic somatic motor activity influencing both alpha and gamma motor neurons
  • Orphenadrine is an anticholinergic used to treat spasms of various etiologies ( i.e. lumbargo and sciatica
53
Q

Cyclobenzaprine

A
  • Related to tricyclics
  • Serotonergic and noradrenergic
  • Used for short term treatment of spasticity, not effective for treatment of spasticity
  • Drowsiness, loss of coordination, anticholinergic, dizziness, physical dependence,
  • At high doses: areflexia, flaccid paralysis, respiratory depression, tachycardia, hypotension
54
Q

Methocarbamol

A
  • Related to tricyclics
  • Short term treatment of skeletal muscle spasms, but not effective for treatment of spasticity
  • Drowsiness, loss of physical coordination, light headedness, dizziness, discoloration of urine
  • After parenteral administration: syncope, hypotension, bradycardia, ataxia and vertigo, seizures, hemolysis
  • Addicition and physical dependence
  • CNS and respiratory depressions
55
Q

Spasticity

A
  • Increase in tonic stretch reflexes and flexor muscle spasms with muscle weakness
  • Usually associated with brain or spinal cord injuries (loss of supra spinal inhibitory influence on alpha motor neurons
  • Contractions are velocity dependent, greater resistance with faster stretches
56
Q

Treatment of spasticity

A
  • Reduce pain, frequency of spasms or irritating stimuli
  • Improve gait, hygiene, and ADLs
  • Multi-disciplinary approach
57
Q

Baclofen

A
  • Oral: Decrease spasticity due to multiple sclerosis and SC injury, can also be used for trigeminal neuralgia
  • Intrathecal: Takes a lower dose and has fewer side effects. Used for Cerebral palsy, anoxic brain injury, MS, stroke, SC injury, AV malformation
  • MOA: Binds presynaptic GABA B receptors which decreases Ca influx in presynaptic terminals which depresses the release of glutamate, aspartate, and reduces substance P release from nociceptive afferent nerve terminal
58
Q

Depolarizing NMBD agents

A
  • Agonists at nACh Receptors
  • Depolarize end plates
  • Produce fasciculations
59
Q

Non-Depolarizing NMBD agents

A
  • Competitive antagonists for nACh receptors, can also block pore of channel
  • induce flaccid paralysis
  • Do not depolarize end plate
  • No fasciculation
60
Q

NMDB structure

A

related to acetylcholine

61
Q

Sensitivity to block by NMBDs

A

-Rapidly moving muscles > limbs > trunk> diaphragm

62
Q

Succinylcholine

A
  • Only brief relaxation required
  • Rapid short action hydrolyzed by cholinesterase
  • No crossing BBB
  • Phase 1 Succinyl binds to nAChR and causes depolarization, not metabolized by ACh esterases leads to membrane remaining depolarized –> flaccid paralysis
  • Phase II: Membrane may become repolarized but can’t be depolarized again (desensitized)
  • BLOCKAGE CANT BE REVERSED BY ACh ESTERASE INHIBITORS
63
Q

Succinylcholine metabolism

A
  • Plasma cholinesterases hydrolyze in liver
  • Only small fraction of drug reaches NMJ
  • Block terminated by diffusion
  • Side effects: Malignant hyperthermia, stimulate autonomic ganglia, hyperkalemia (release of K+) , myoglobinuria,
64
Q

Blockage due to non-depolarizing blocker

A

-Can be reversed by ACh esterase inhibitor (edrophonium and neostigmine) allow ACh to build up and compete with NMDB

65
Q

ND NMDB PK

A
  • Dont cross BBB
  • Rapid distribution followed by slower elimination
  • Eliminated by plasma cholinesterases, excreted by kidney, metabolized by liver, spontaneous breakdown
66
Q

Atracurium

A
  • Slower onset of action with intermediate duration
  • Organ-independent metabolism
  • Laudanosine is a non-active metabolite (convulsions)
  • Dose dependent histamine release
  • Hemodynamic instability and bronchospasms
67
Q

Cisatracurium

A
  • Slow onset with intermediate duration
  • Organ-independent metabolism
  • Less laudanosine is produced (appropriate for infusion)
  • Much less histamine is released compared to atracurium
68
Q

Methotrexate: USES, Structure, and PK

A
  • Used in early RA, RA w/ poor prognosis, generally first choice
  • Orally or subq (bioavailability and fewer side effects) once/week (hepatoxicity) may take 4-6 weeks for effects
  • Folic acid analog used for chemo, enter cells via folate transporter and is polyglutamated (traps and increases half-life)
69
Q

Methotrexate: MOA

A
  • Mech 1: inhibit purine synthesis by inhibiting dihydrofolate reductase and tetrahydrofolate formation (anti-cancer)
  • Mech 2: Inhibits AICAR –> increase in adenosine –> resolution of inflammation (maybe major benefit in RA)
  • Mech 3: Inhibits thymidylate synthetase –> reduction in thymidine levels –> inhibition of inflamm cell proliferation
70
Q

Methotrexate: Side effects

A
  • Rare hepatotoxicity with high doses, reason for once/week dosing, NO ETOH, Elevation of liver enzymes, Don’t use with liver failure
  • NO RENAL INSUFFICIENCY
  • NO PREGNANCY
  • PULMONARY TOXICITY
  • INCREASE INFX
  • GIVE FOLATE 24 hrs. after administration to counteract side effects
71
Q

Hydroxychloroquine

A
  • Antimalaria drug thought to act by altering intracellular pH
  • Orally effective with slow onset and LONG half-life
  • Frequently used with MTX and/or sulfasalazine
  • RETINAL DAMAGE (eye exams) more common with renal insufficiency
  • hypoglycemia in diabetics (possible reduction in incidence of T2DM)
  • Safe in pregnancy
  • DONT USE WITH PSORIASIS OR PORPHYRIA
  • Caution with neurological, hepatic, or hematologic disorders and alcoholism
72
Q

Sulfasalazine

A
  • Immune suppressive drug frequently used with hydroxycholorquine and MTX
  • Orally effective –> salicylate and sulfapyridine (both poorly absorbed by affect GI immune system
  • Skin reactions (urticaria, rash, and pruritus)
  • Blood dycrasias in first 3-6 months
  • Reduction in folate absorption so supplement
  • DONT USE W/ SULFA or CELEBREX allergies
73
Q

Triple Drug therapy

A
  • Methotrexate weekly
  • Try Hydroxychloroquine plus sulfasalazine daily
  • try all three in combo
  • Can add prednisone or NSAID
  • Multiple drugs with synergist actions –> less side effects than any one drug by itself
  • Goal: markedly slow or stop disease progression, ideally disease remission not just to relieve symptoms
74
Q

Leflunomide

A
  • Immunosuppressive agent which inhibits dihydro orotate (pyrimidine synth) and tyrosine kinase at higher doses.
  • Inhibits T-Cell proliferation and reduces auto-antibody formation
  • Orally daily –> teriflunomide (active agent)
  • Extremely long half-life due to enterohepatic recirc.
  • Cholestyramine to clear drug from body
  • Inhibits CYP P450s
  • Teratogenic and carcinogenic
  • ABSOLUTELY CONTRAINDICATED DURING PREGNANCY need 2 negative tests two weeks apart
75
Q

MInocycline

A
  • Tetracycline antibiotic which inhibits metalloproteinases and collagenases
  • Inhibits collagen degradation component of RA
  • Effective one or twice daily in seropositive RA
  • No real side effects
76
Q

Biological response modifiers

A
  • Peptides or proteins
  • advances in making and suing peptides as drugs
  • Target individual specific mediators early in inflame signaling cascade
  • Start when tDMARDS fail as add on agent. More effective in combo with MTX
  • Increased risk of info (TB, URI, herpes zoster, fungal)
  • Blood dyscrasias
  • Increased cancer incidence
77
Q

ANTI-TNF

A
  • Etanercept, Infliximab, Adalimumab
  • Cytokine central to immune and inflammation, upstream regulator of many other immune/inflammatory cytokines
  • Promotes inflammation and Joint destruction
78
Q

Etanercept

A
  • 2 Soluble p75 subunit of TNF receptor linked the the Fc domain of IgG1
  • Binds TNF and prevents binding to cellular receptors inhibiting all steps down stream
  • Protein, SC weekly, shortest duration
  • Possible PML (rare viral infection of CNS
  • Cancer risks similar to methotrexate
79
Q

Infliximab

A
  • Monoclonal antibody against TNF, not part of TNF receptor (mouse-human chimera)
  • Administered IV 4-8 weeks always combined with MTX and other DMARDs
  • Hypotension
80
Q

Adalimumab

A
  • Anti-TNF antibodies like infliximab (not part of TNF receptor just antibody against
  • Fully humanized
  • Injected SC every 2 weeks
  • Approved for juvenile idiopathic arthritis
  • Causes demyelination so contraindicated in patients with demyelinating disease like MS
81
Q

CTLA-4, CD-80, and CD-28

A

CD-28 = T-Cell surface protein that recognizes activated APCS
CD-80 = on APCs is the CD-28 receptor
CD-80 and CD-28 binding activates the T-Cell
CTLA-4 is an antagonist for CD-80 that keeps CD-28 from binding there

82
Q

Abatacept

A
  • CTLA-4 Analog
  • CD 28 receptor antagonist (binds CD-80)
  • T-Cell activation inhibitor
  • IgG1 and CTLA-4 binding domain fusion protein
  • Injected SC weekly or IV monthly
  • Severe RA not responsive to other DMARDS
  • Serious INFX
  • Infusion reactions (bronchospasm, angioedema, hypotension
  • NOT COMBINED WITH TNF INHIBITORS (increased risk of INFX)
  • NOT WITH PEOPLE WHO HAVE COPD
83
Q

Rituximab

A
  • Anti-CD20 monoclonal antibody and therefore and B cell inhibitor
  • IV two injections two weeks apart
  • Used w/ MTX
  • Dont Use with anti-TNF
84
Q

Concentration gradient and second gas effect

A

-Bulk uptake of one gas increases apparent concentration of second gas causing increase absorption of 2nd gas.

85
Q

Elimination of Anesthetic

A
  • Reverse process -> exhalation
  • More blood soluble agent -> hangover
  • Diffusion back in to the lungs can result in hypoxia b/c partial pressure increases -> decreased partial pressure of O2
  • Currently used agents are only minimally metabolized b/c metabolites are toxic
86
Q

Potency of inhalation anesthetics

A
  • Minimum concentration of agent required to induce anesthesia
  • MAC = minimum partial pressure that prevents movement in 50% of adult patients
  • MAC ISN’T related to induction time.
87
Q

Calcineurin Inhibitors (Cyclosporine): MOA

A
  • Interferes with T-Cells by binding to cyclophilin to for a calcineurin inhibitory complex
  • Calcineurin activates NFAT which leads to IL-2 transcription
  • IL-2 activates T-Cells
88
Q

Calcineurin Inhibitors (Cyclosporine): PK, and Therapeutic uses

A

-PK: Poor oral, CYP 3A4 (grapefruit juice), individual dosing and blood level monitoring
Uses: Prevent rejection of allogenic kidney, liver, lung, and heart, usually given with glucocorticoids
-DOESNT REVERSE ACUTE EPISODES OF ESTABLISHED REJECTION
-Psoriasis, and rheumatoid arthritis
-Dry eyes

89
Q

Calcineurin Inhibitors (Cyclosporine): adverse effects

A
  • CsA ISNT MYELOTOXIC!
  • Nephrotoxicity: does dependent and reversible, reduction in RBF due to fibrosis
  • HTN: renal vasoconstriction and Na retention
  • Tremor, hirsutism, gingival hyperplasia
90
Q

Calcineurin Inhibitors (Tacrolimus): MOA and Uses

A

-Similar to CsA (not in structure)
-Binds to FKBP-12 and forms a complex that inhibits calcineurin
-More potent and better efficacy than CsA
USES:
-Prevent rejection of kidney, liver, lung and heart with glucocorticoids
-Psoriasis and rheumatoid arth
-Topical for atopic dermatitis, and oral for ulcerative colitis

91
Q

Calcineurin Inhibitors (Tacrolimus): PK and Adverse effects

A
  • CYP3A4
  • nephrotoxicity
  • Neuro: seizures and tremors
  • Hyperglycemia and diabetes
  • HTN
92
Q

mTOR Inhibitors (Sirolimus): MOA and Uses

A

MOA:
-Binds and complexes with FKBP-12 that then binds to and inhibits the MTOR complex 1
-MTOR complex 1 is a serine threonine kinase and inhibition arrests T-Cell division in G1 phase
USES:
-Kidney transplant rejection in combo with CsA B/C lower risk of kidney toxicity
-Steroid refractory acute and chronic GVHD
-CAD

93
Q

mTOR Inhibitors (Sirolimus): PK and Adverse effects

A
PK: 
-60 hr T1/2 
-CYP3A4 and P-glycoprotein elimination
Adverse:
-Profound myelosuppression
-Poor wound healing
-Incr. serum cholesterol and triglycerides (STATIN)
-NOT FOR LIVER OR LUNG TRANSPLANT
94
Q

Cytotoxic (Antiproliferative) Agents (Azathioprine): MOA, Uses, and Adverse effects

A
MOA: 
-Prodrug of 6-Mercaptopurine
-Direct antiproliferative (s-phase) effects on activated T-cells and reduces B-Cell activation but less effects on antibody production
USES:
-Adjunct with other agents to prevent rejection
-RA in NON-PREGNANT PATIENTS
AE:
-Myelosuppression
-Mutagenic and teratogenic
-Dose reduction w/ pts on Allopurinol
95
Q

Cytotoxic (Antiproliferative) Agents (Mycophenolate Mofetil): MOA, Uses, AE, and PK

A

MOA:
-Prodrug of mycophenolate
-Highly specific for T and B lymphocytes due to heavy reliance on de novo pathway for purine synthesis
-Reversible non-comp inhibit of lymphocyte inosine monophosphate dehydrogenase
Uses:
-Heart, liver, kidney transplants,
Adverse effects:
-GI effects, myelosuppression, infections
PK:
-converted by plasma esterases to MPA