FINAL Flashcards
(125 cards)
1
Q
First order kinetics
A
- constant FRACTION of drug eliminated/unit time
- clearance directly proportional to concentration
- most drugs
- curved graph
2
Q
Zero order kinetics
A
- constant AMOUNT of drug eliminated/unit time
- independent of concentration
- ETOH, ASA, dilantin
- linear graph
3
Q
Half life
A
Amount of time it takes for 1/2 of drug to be cleared
4
Q
Steps for determining degree of ionization of drug
A
1) is drug acidic or basic?
2) what is the pH of the tissue?
3) what is the pKa of the drug?
4) Is the pKa becoming more acidic or basic?
5) if 1 and 4 are the same= more unionized; if different= ionized
5
Q
What % of the drug is nonionized and ionized if pKa and pH are the same?
A
50/50
6
Q
what is pKa?
A
dissociation constant
7
Q
What processes are in phase 1 reactions and what do they do?
A
- oxidation- lose electron
- reduction- gain electron
- hydrolysis- split apart and add H2O
8
Q
What carries out phase 1 reactions and what is the final product?
A
CP450- converts drug into polar metabolite
9
Q
What is the phase 2 reaction?
A
Conjugation- adds polar, water soluble substrate to molecule to make it biologically inactive and ready for excretion
10
Q
What are the enzymes involved in phase 2 reactions?
A
glucuronic acid, GST, N-acetyl-transferase, sulfotransferases
11
Q
full agonist
A
drug has effect on receptor- high receptor affinity and high intrinsic activity- full effect
12
Q
inverse agonist
A
binds to receptor and causes opposite effect
13
Q
partial agonist
A
has high receptor affinity but only partial intrinsic activity
14
Q
agonist-antagonist
A
partial agonists that also have antagonistic activity (may decrease effects of full agonists)
15
Q
Antagonist
A
binds to receptor but blocks effect (no response)
16
Q
Competitive vs non-competitive antagonist
A
competitive (can be reversed- ex Narcan); noncompetitive (cannot be reversed)
17
Q
What tests evaluate effectiveness of heparin?
A
aPTT- normal is 30-35, therapeutic is 1.5-2x baseline)
ACT- normal is 90-120; therapeutic >300, <180 inadequate (measure baseline, 3 min out, and q30m after)
18
Q
What tests evaluate effectiveness of warfarin?
A
PT- normal 10-14 seconds
INR- therapeutic 2-3
19
Q
What monitors effectiveness of ASA?
A
no lab value- ASA is irreversible and lasts for lifetime of platelet (d/c 4-7 days preop)
20
Q
What is bleomycin used for?
A
testicular cancer (blue balls)
21
Q
What is a complication of bleomycin?
A
pulmonary toxicity (blebs)
22
Q
Oxygen consideration with bleomycin?
A
maintain FiO2 below 30%
23
Q
What is doxorubicin (adriamycin) used for?
A
mainly metastatic breast cancer (and others)
24
Q
What is a complication of doxorubicin?
A
cardiotoxicity- may potentiate myocardial depressant effects of anesthetics
25
Dosing of Ancef
must decrease with renal dysfunction- excreted primarily by GFR
*with normal renal function, consider redosing 4 hours from initiation of preop dose
26
Elimination half time of vancomycin (normal vs renal failure)
6 hours vs 9 days
27
What type of "ring" do penicillins have?
thiazolidine ring connected to beta-lactam ring
28
How does chlorhexidine work?
disrupts cell membrane of bacterial cells
29
Chlorhexidine vs iodine and hexachlorophene
chlorhexidine more effective
30
What is chlorhexidine used for?
mainly pre-op to decrease cutaneous bacteria
31
Where should you avoid contact with chlorhexidine?
eyes and ears
32
What has the overuse of antibiotics led to and what are they normally prescribed for?
bacterial resistance; URIs/bronchitis
33
Nearly ? % of nosocomial infections occur at the following 3 sites:
80%; urinary tract (catheters), respiratory system (ventilators), bloodstream (vascular access catheters)
34
What is the most common nosocomial bloodstream infection and what is it treated with?
S. aureaus- vancomycin
35
What 2 broad categories can bacteria be divided into?
gram positive and negative
36
Gram positive bacteria
retain violet color of stain (acne, MRSA)
37
Gram negative bacteria
have largely impermeable cell wall- more resistant to antibiotics (lyme, pneumonia)
38
What can happen if you administer vancomycin too fast?
red man syndrome- massive histamine release, facial/truncal erythema- can cause hypotension and cardiac arrest (if given <30 minutes)
39
What are side effects of aminoglycosides that decrease their clinical usefulness?
ototoxicity, nephrotoxicity, potentiation of NMDA, skeletal muscle weakness (parallels plasma concentration- consideration with renal dysfunction)
40
What are SCIP measures and what is anesthesiology responsible for?
measures to decrease the incidence of nosocomial infections- responsible for glucose management, normothermia, antibiotics
41
SCIP measures
- prophylactic ABX within 1 hr of surgery and d/c within 24 hours
- controlled serum glucose (<200 at 0600)
- normothermia
- wound infection identified during admission
- appropriate hair removal
42
What is pasteurization?
disinfection by way of hot water (destroys cell proteins)
43
What organisms is pasteurization effective against?
gram negative, M. tuberculosis, most fungi and viruses
44
Thiazide diuretics
- work on ascending loop and distal tubule
- prevent reabsorption of Na and Cl
- ex) hydrochlorothiazide
45
Loop diuretics
- work on ascending loop of Henle
- inhibit Na and Cl reabsorption
- ex) Lasix
46
Osmotic diuretics
- work along whole nephron
- prevent reabsorption of water
- ex) mannitol
47
Aldosterone antagonists
- work on collecting duct
- prevent Na and Cl absorption and K secretion
- ex) spironolactone
48
potassium sparing diuretics
- work on DCT
- inhibit Na, Cl, HCO3 reabsorption AND K secretion
- ex) triamterene
49
Carbonic anhydrase inhibitors
- work on PCT
- inhibit reabsorption of HCO3
- ex) acetazolamide
50
dopamine receptor agonists
- work along renal tubule
- stimulate dopamine 1 receptors
ex) dopamine
51
What anti-eleptic medications are liver enzyme inducers?
dilantin (phenytoin), carbamazepine- increases clearance, requiring larger doses of drugs to achieve effect
52
What anti-seizure med is often given during neurosurgery?
Keppra, phenytoin?
53
What mental health med is often given for neuropathic pain and post op management pain?
amitriptyline and imipramine (TCAs); maybe gabapentin?
54
What is the relationship between steroids and pain?
corticosteroids are often given to prevent post-op pain because they inhibit the phospholipase enzymes and COX pathway- also have anti-inflammatory effects
55
Consideration of hypoglycemia and general anesthesia
GA can mask symptoms of hypoglycemia (tachycardia, sweating, hypertension, seizure, coma)- also can be masked by beta antagonists
56
What is a serious complication of metformin?
lactic acidosis- those especially at risk: liver dysfunction, MI, CHF, dehydration, renal dysfunction, IV contrast, hypoxemia, sepsis
57
When should you d/c metformin pre-op?
48 hours
58
Very rapid acting insulins
- aspart, lispro, glulisine
- onset 5-15 minutes
- peak 45-75 minutes
- duration 2-4 hours
59
Rapid acting insulin
- regular
- onset 30 minutes
- peak 2-4 hours
- duration 6-8 hours
60
Intermediate acting insulin
- NPH
- onset 2 hours
- peak 4-12 hours
- duration 18-28 hours
61
Long acting insulin
- detemir, glargine
- onset 1.5-2 hours
- peak 3-9 hours (detemir)- glargine has no peak
- duration- detemir (6-24 hours) glargine (20-24+)
62
Very long acting insulin
degludac
- onset 2 hr
- no peak
- duration 40 hours
63
CZ insulin
rapid acting,
0.5-1 hour onset
2-3 hour peak
6-9 hour duration
64
Which fish substance is thought to have lipid lowering properties?
fish oil- reduces triglycerides and possibly LDL (not FDA regulated)
65
Why do we favor nonparticulate clear antacids in anesthesia?
rapid mixing with gastric contents, more reliable increase in gastric pH, less aspiration risk
66
Examples of nonparticulate antacids
bicitra, polycitria, sodium citrate
67
What gastric motility agent should be avoided in Parkinsons and why?
Reglan- antidopaminergic drug (Parkinsons are already low in dopamine- drug may cross BBB and cause EPS)
68
Alpha phase
distribution of drug from central to peripheral compartments
69
beta phase
excretion of drug (longer, less steep)
70
Why do patients awake from propofol?
redistribution into periphery (alpha phase)
71
How do you reverse warfarin?
- Vitamin K 1-2 mg (slow)
- FFP 1-2 units
- recombinant factor VIIa
- Kcentra (prothrombin complex concentrate)
72
What are TXA and aminocaproic acid?
antifibrinolytics (prevent clot breakdown by inhibiting conversion of fibrinogen to fibrin)
73
TXA considerations
high concentrations may actually inhibit fibrin and may cause seizures
74
What are TXA and aminocaproic acid often used in?
cardiac procedures
75
How does warfarin work?
inhibits Vitamin K epoxide reductase from converting clotting factors into their activated form
76
What is DDAVP and how does it work?
analog of vasopressin that stimulates release of vWF from endothelial cells (binds to glycoprotein Ib receptors, causing platelet adherence)
77
What is DDAVP used for?
hemophilia A and vWF disease
78
Examples of pro-hemostatic agents
DDAVP, antifibrinolytic agents (aprotinin, epsilon aminocaproic acid, TXA), protamine, factor concentrates, prothrombin concentrates, recombinant factor VIIa, topical thrombin agents
79
What do prohemostatic agents do?
promote clot formation or prevent clot degradation- used to treat hemorrhage
80
Protamine
- heparin reversal
| - 1 mg for every 100 units of heparin (or 10/1000)
81
Protamine considerations
must be given SLOW (at least 5 minutes)- can cause hypotension
82
What is protamine made from?
salmon sperm- contraindicated in fish allergy
83
What is serotonin syndrome?
condition of too much serotonin agonism- combo of SSRIs, TCAs, MAOIs
84
clinical findings of serotonin syndrome
tremors, AMS, clonus, HYPERTHERMIA
85
What is lovastatin made from?
naturally occurring from aspergillus terreus
86
What is fluvastatin made from?
entirely synthetic
87
Main side effect of statins?
muscle aches- can even cause rhabdo, high CK
88
Which steroid has the highest anti-inflammatory property in relation to cortisol?
Decadron (25x) and betamethasone
89
What is the primary treatment for hypothyroidism?
steroid replacement therapy
90
What have epidural injections of corticosteroids been used for?
back pain due to root irritation
91
Dermatologic side effects of steroids
hirsutism, skin thinning, cushingoid, alopecia, acne, striae, hypertrichosis
92
Eye side effects of steroids
glaucoma, exopthalmos, cataracts
93
CV side effects of steroids
HTN, increased serum lipoproteins, atherosclerosis, arrhythmias
94
GI side effects of steroids
gastritis, steatohepatitis, PUD, visceral perforation, pancreatitis
95
Renal effects of steroids
hypokalemia, fluid volume shifts
96
GI and reproductive effects of steroids
amenorrhea/infertility, intrauterine growth retardation
97
bone side effects of steroids
avascular necrosis, osteoporosis
98
muscle side effects of steroids
myopathy
99
neuropsychiatric side effects of steroids
insomnia, dysphoria/depression, euphoria, psychosis, pseudo tumor cerebri
100
Endocrine side effects of steroids
diabetes, hypothalamic-pituitary-adrenal insufficiency
101
Infectious side effects of steroids
heightened risk of infection, opportunistic infections, herpes zoster
102
What is a stress dose and who do you give it to?
Solu Cortef 100 mg- give to those taking high dose steroids preop
103
Radioiodine is used as treatment for what?
Grave's hyperthyroidism
104
treatment for hyperthyroidism
antithyroid drugs (methimazole, propylthioracil, carbamazole), iodine, surgery
105
What herb is used as an antidepressant and was shown to be more effective than a placebo?
St John's Wort- more effective than low dose TCAs and may be as effective as SSRIs
106
What is caused by a Vitamin C deficiency and what are the symptoms?
scurvy- gum lesions, hemorrhage
107
What substances are high in Vitamin C (ascorbic acid)?
citrus fruits
108
What deficiency causes neural tube defects in pregnant women?
folic acid
109
What herbs impair blood clotting?
garlic, ginger, gingko biloba
110
What are the fat soluble vitamins?
ADEK
111
What mineral is important for strong bones and who is susceptible to deficiencies?
calcium- elderly (osteoporosis)
112
What vitamin is associated with blood clotting and where is it found in the diet?
Vitamin K- green leafy vegetables
113
Who should avoid green leafy vegatables?
Those on blood thinners (Afib)
114
Is there a lab test to monitor Eliquis?
no
115
Medications processed by zero order kinetics
ETOH, ASA, dilantin, warfarin, heparin, theophylline
116
Drug receptor equation
Drug (D)+receptor (R)= drug receptor complex (DRC)= tissue response
117
DRC is ? whereas tissue response ?
constant; varies
118
Potency
increased affinity for drug shifts drug response curve to the left (need less drug to achieve effect)
119
Slope of drug response curve
the steeper the slope, the more receptors are occupied
120
Efficacy of drug response
plateau- the higher it is, the greater efficacy; tissue response
121
synergistic effects
summing of simultaneous drugs have a greater combined effect than the effect of either one when given alone (1+1=3, acting on different receptors)
122
additive effects
two substances have total effect of sum of individual effects (1+1=2, act on same receptors)
123
potentiation
effects of one drug enhanced by another with no effect of its own (1+0=3)
124
Antagonism
effect of one drug cancels effect of another (1+1=0)
125
What can the concurrent use of sympathomimetics and MAOIs result in?
hypertensive crisis
