**Quick Hits Flashcards
(141 cards)
1
Q
Examples of zero order kinetics?
A
Aspirin
Phenytoin
Warfarin
Heparin
Theophylline
2
Q
Zero vs First order kinetics?
A
Zero - Constant amount of drug is eliminated
First - Constant Fraction of drug is eliminated
3
Q
What are the three examples of phase 1 reaction?
A
Oxidation- Removes electron
Reduction - Adds electron
Hydrolysis- Adds water (ester)
4
Q
Theophylline has a low hepatic extraction ratio. Which will have a greater effect on metabolism - prolonged hypotension or CYP inhibition?
A
CYP inhibition
**
1. High hepatic ER (>0.7) is dependent on perfusion
2. Low hepatic ER (<.3) is dependent on enzymes
5
Q
How do enzyme inducers affect clearance?
A
Increase clearance — require more drug
Ex: tobacco, ethanol, barbituates
6
Q
How do enzyme inhibitors affect clearance?
A
Decrease clearance
Need less drug
Ex: Grapefruit, SSRI
7
Q
What is potency and how is it measured?
A
Dose required to achieve clinical effect.
8
Q
What is the ED50 and ED90 a measure of?
A
Potency.
How much drug to achieve clinical effect in 50% and 90% of the population
9
Q
Drug A is further left on the curve, what does this mean?
A
10
Q
When two drugs has the same efficacy, but one is further left, what does this mean?
A
Both can achieve the same clinical effect, but need a higher dose of Drug B
11
Q
What does the slope of the dose response curve tell you?
A
Steeper slope means a small increase in drug has a profound effect
Flatter slope means a higher dose is required to increase its clinical effect
12
Q
What is therapeutic index? How is it measured?
A
TD50/ ED50
Wide TI means a wide margin of safety
Narrow TI means a small margin of safety
13
Q
What is a racemic mixture?
A
Equal amounts of two enantiomers
Ex: Bupivacaine, iso, des, ketamine, ephedrine
14
Q
Two ways propofol is cleared from the body?
A
- PY450
- Lungs
15
Q
When should Ketamine be given? When shouldn’t it? How does it effect each system?
A
NEED INTACT SNS
- Increases everything
- Bronchodilates
- Relives somatic pain
- Blocks wind up
16
Q
When should etomidate not be given? What is helpful with?
A
- Does not cause seizures with no seizure history BUT great for mapping seizures with hx of them
- Great hemodynamic stability with mild respiratory effects
- NEVER give with adrenocortical issues like sepsis
17
Q
What drugs should be avoided in porphyria ?
A
Barbs
Etomidate
Ketamine
Amio
Toradol
18
Q
How is porphyria treated?
A
Fluids
Glucose
Heme arginate
Normothermia
19
Q
Gold standard of ECT?
A
Methohexital - decreases seizure threshold
20
Q
How do most GABA agonists work? What about benzos?
A
Most increase channel time
Benzos- Increase frequency
21
Q
Which induction drugs have an active metabolite?
A
Ketamine
Versed
22
Q
Blood: Gas solubilities?
A
Des - .42
N2O - .46
Sevo - .65
Iso - 1.45
23
Q
What are the 4 tissue groups? Amount of CO for each group?
A
Vessel rich (10%) - 75% of CO
Muscle (50%) - 20% of CO
Fat (20%) - 5% of CO
Vessel poor (20%) 1%
24
Q
How do gases effect cerebral blood flow?
A
Uncouples, CMRO2 decreases and CBF increases
Nitrous does not uncouple
25
What is a MAC hour?
1% sevo x 2 hours
2% sevo x 1 hour
4% sevo x 30 minutes
26
Which gas is not metabolized to TFA?
Sevo
27
What is diffusion hypoxia ? How is it treated?
N2O dilutes alevolar O2 and depresses respiratory drive
Treat with 100% O2 for 3-5 minutes
28
Which inhalation anesthetics are most greatly effected by R-L shunt?
Des (lower solubility)
29
Which inhalation anesthetics are most greatly effected by L-R shunt?
None
30
How many more times soluble is nitrous?
34x
31
How long should nitrous be avoided when placing an SF6 bubble? What is a safe to use with nitrous?
7 days
Silicone oil has no contraindication
32
What factors do not affect MAC?
K
Mag
Thyroid
Gender
HTN
33
What is the meyer-overton rule?
Lipid solubility is directly proportional to potency
34
Most important site of halogenated anesthetic c action on the brain?
GABA
35
How does Nitrous work?
NMDA antagonism
P2P channel
36
Which gas contributes to conoral steal syndrome?
Iso
37
Which factor influences anesthetic uptake the least?
FGF
38
What determines local onset of action?
pKa
**closer pKa is to pH, the faster the onset
39
What determines local anesthetic potency? What is the secondary determinant?
Lipid solubility
Intrinsic vasodilating effect
40
What determines duration of action?
Protein binding*
41
Which local has the lowest protein binding?
Chloroprocaine - 0
Procaine - 6
42
Which local has the highest pKa? Lowest?
Procaine - 8.9
Mepivacaine - 7.6
43
Rank injection sites with highest Cp
IV
Tracheal
Interpleural
Intercostal
Caudal
Epidural
Brachial
Femoral
Sciatic
Subq
44
Max dose of chloroprocaine with epi?
1000
45
Max dose of lidocaine? with epi?
300
with epi - 500
46
Max dose of Bupivacaine? With epi?
175
with 200
47
Which local has high cardiotoxicity?
Bupivacaine
48
Most common sign of local toxicity?
Seizure except bupivacaine is cardiac arrest
49
What are appropriate levels of locals?
1-5
50
What level are first symptoms seen with locals?
5-10
51
What level is cardiovascular collapse seen?
>25
52
What conditions increase LAST?
Hypercarbia
Hyperkalemia
Metabolic acidosis
53
Best choices for treatment of LAST?
Amiodarone and Lipids
Avoid epi, vasopressin
54
Max dosage for tumescent anesthesia ? What other complications are seen?
50mg/kg
Pulmonary edema, LAST
55
What two locals produce a leftward shift on the oxyhemoglobin dissociation curve?
Prilocaine and benzocaine
Also
Cetacaine
EMLA (Prilocaine+lidocaine)
AND
Nitro, Nipride, Phenytoin
56
Treatment of methemoglobinemia ? Who is at high risk?
Methylene Blue
Glucose-6-phosphate deficiency
Infant
57
What drugs are adjuncts for locals?
Clonidine
Epi
Opioids
58
Which local reduces the effectiveness of opioids?
Chloroprocaine
59
What drug helps locals diffuse through tissue?
Hyaluronidase
60
Patients with upregulation of extra junctional receptors need more or less of: depolarizers, nondepolarizers?
*DO NOT USE SUCC
*Need more Non depolarizers
61
Is fade observed with Succ?
NO
Phase 1 blocks will either have twitches or no twitches
*amplitude will be decreased
62
Phase 1 vs Phase 2 block
1- no fade
2- fade present
63
Where is onset of NMB best measured? Recovery?
Onset - Oculi
Recovery - Ulnar
64
Is succ safe with renal failure?
Yes if normal K level
65
What is the Dibucaine test? What is normal?
Normal is 80, which means dibucaine has inhibited 80% of pseudocholinesterase
66
What is the treatment for hyperkalemia arrest caused by succ? Why?
Ca - it raises the RMP
67
Highest rates of myalgia following succ?
Young adults, specifically women
Children, elderly, pregnant have the lowest
68
How can myalgia be reduced? What does not help?
ROC
NSAIDS
Lidocaine
Higher dose of succ
**opioids do not help
69
Order of NMB from highest to lowest
Roc
Atra
Miv + Panc
Vec
Cis
70
What is the metabolite of atra and cis? Why does this matter?
Laudanosine - increases seizure
71
Where is roc metabolized? active metabolite?
Liver
72
Do vec and panc have active metabolites?
Yes
73
Which NMB have a histamine release?
Succ, atra, miv
74
Which NMB has a vagolytic effect?
Panc
75
Which NMBs should be avoided with hypertrphic cardiomyopathy?
Panc, Atra, miv
76
What is the main way to inhibit acetylcholinesterase?
Formation of carbamyl esters
Ex; Neostigmine, pyridostigmine, Physostigmine
77
Which AchE inhibitor passes through the BBB?
Physostigmine
78
Common side effects of giving too much AchE I?
Increased in PNS
79
Which antimuscarinic does not pass through the BBB?
Glyco
80
When can atropine cause paradoxical bradycardia?
Too small of a dose
81
How does inflammation effect pain transduction?
Reduced threshold to pain (Allodynia)
Increased response (hyperalgesia)
82
Max dose of cocaine?
200mg
83
What is EMLA cream consist of? Dressing? Onset of action?
50% Lidocaine and 50% Prilocaine
Onset - 1 hour
Need dressing
84
Which local is metabolized to o-toluidine?
Prilocaine
85
What is the metabolite in ester locals?
Para-aminobenzoic acid
86
Easy calculation for bupivacaine?
0.5% - divide weight in half
1.0% - 1 per / kg
87
Which local is unionized?
Benzocaine
88
Which Ion does not pass through the nicotinic receptor?
Chloride
89
Which antiemetic can prolong succ duration?
Metoclopramide
90
What is Hoffmans elimination dependent on?
pH and temperature
91
Which agent potentiates NMB the most?
Des
92
What test confirms anaphylactic to a NMB?
Tryptase
93
Do locals have an effect on TMP or RMP?
NO
94
Are local's weak acids or bases?
Weak bases
95
What is the MOA of locals?
Conjugate acid binds to the INTRAcellular sodium channel
96
Max dose of experal?
266 mg or two vials
97
Dose of lipids for LAST?
1.5mg/kg
98
Most common cause of death with patients undergoing tumescent? When is a general indicated?
PE
Greater than 2-3 liters being used
99
Which additives prolong duration of action of locals?
Dextran
Epi
Dexamethasone
100
What conditions are contraindicated with succ?
Guillain Barre
MS
Marre Tooth
101
Ester linkage drugs undergo what type of metabolization?
Hydrolysis
102
Which Ca channels are blocked?
L type
103
Which disease is seen with a strawberry tongue and an increased risk of coronary artery aneurysm?
Kawasaki's disease
104
Most common cause of death with an LVAD?
Infection
105
What does the Law of LaPlace explain?
AAA
Tension = Pressure * Radius
106
What does the low pressure test, test?
Flow control valves to the common gas outlet
107
What conditions cause a large V wave?
Tricuspid regurgitation
Acute increase in volume
RV papillary muscle ischemia
108
Normal PAOP (wedge pressure)
5-15
109
What conditions cause PAOP to underestimate LVEDV?
Aortic regurgitation
110
When does thermodilution underestimate CO?
Too cold
Too much volume
111
When can't thermodilution predict CO?
Tricuspid regurg
Shunt
112
On a PA waveform, where is the catheter when there is a increase in diastolic pressure but systolic stays the same?
Tip is in the PA
113
On a PA waveform, where is the catheter when there is a increase in systolic pressure but diastolic stays the same?
RV
114
What opioids produce a metabolite? What do they cause?
Meperidine - seizures
Morphine - Resp depression
115
Which opioid has the largest Vd? Smallest?
Largest - Fent
Smallest - Remi
116
What is the only opioid that antagonizes NMDA?
Methadone
117
Which opioid can cause prolonged QT?
Methadone
118
Best treatment for muscle rigidity?
Paralysis and intubation
119
Common characteristics of partial opioids?
-Produce analgesia with reduced respiratory depression
-Ceiling effect
-Reduce the efficacy
-Can cause withdrawal
-Low addiction
120
Which opioid reversal is least likely to reverse respiratory depression?
methylnaltrexone
121
Which opioid antagonist has the longest duration of action?
Naltrexone
122
How is the Kappa receptor unique?
Anti shivering
Diuresis
Dysphoria
Delirium
Hallucinations
123
Opioid potency Chart?
124
Mallampati chart
125
LMA sizes
126
What must you do with a grade 4 Cormack and Lehane score?
Use an alternate approach to intubation
127
On a king airway, what lumen is used to ventilate when the tip is in the esophagus? The trachea?
Blue - esophagus
White - trachea
128
What three axis must be aligned when intubating?
Oral
Pharyngeal
Laryngeal
129
During OLV, what is applied first; CPAP or PEEP? Which lung?
1.CPAP to Non-dependent lung is first
2.PEEP to dependent lung second
(C is before P)
(Dependent lung is already doing well)
130
What blood test indicates a higher risk of PPCs?
Albumin < 3.5
131
What does a Mill Wheel murmur signify?
Air embolism
132
On PFTS, with restrictive disease what Dynamic volumes are normal?
FEV1 to FVC ratio and FEF 25-75% are both normal
***Everything else is decreased
133
On PFTS with obstructive disease, what values are normal?
RV, FRC, TLC are all normal
Everything else is decreased
134
With an intrathoracic obstruction, is inhalation or exhalation normal?
Inspiration is normal
(Pulls open obstruction)
135
With an extrathoracic obstruction, is inhalation or exhalation normal?
Exhalation is normal, pushes obstruction open
136
What PFT is the most sensitive indicator of small airway disease?
FEF 25-75%
137
What is a normal FEV1 value?
>80%
138
What is a normal FEV1/FVC ratio?
>80%
139
What tests are used to assess dynamic and static airways?
Dynamic - Moving of air - (PFTs) FEV1. FVC, MMEF, ratio
Static - How much lungs can hold at a single point, RV, ERV, Vt, FRC, TLC
140
What test can measure how well the lungs can transfer gas?
DLCO - diffusing capacity of carbon monoxide
141
Which PFT is the best test of endurance?
MMV - Maximum Voluntary Ventilation over 1 minute
Normal - 150L men
100L women
