Pharm 2 - Exam 2 Flashcards
1
Q
How fast do nonparticulate antacids lose their effectiveness?
A
30-60 minutes after injection
2
Q
Why are traumas always considered a full stomach?
A
GI motility slowed
3
Q
Antacids slow the rate of absorption of what drugs?
A
Digoxin
Cimetidine
Ranitidine
4
Q
Antacids increase the rate of elimination of what drugs?
A
Phenobarbital
5
Q
Metoclopramide is CI with what patients?
A
Parkinsons
6
Q
Rapid IV of metoclopramide
A
Abdominal cramping (CI w/ complete bowel obstruction)
7
Q
What receptor does Narcan have affinity for?
A
Opioid Mu
8
Q
Narcan class
A
Competative opioid antagonist
9
Q
Diphenhydramine class
A
competitively blocks H1 receptors
10
Q
What properties do H1 blockers have?
A
Antimuscarinic and antiserotonergic
11
Q
The antimuscarinic property of H1B contributes to what side effect?
A
dry mouth
12
Q
The antiserotonergic activity of H1B provides this action?
A
antiemetic
13
Q
What 2 actions do H2B accomplish?
A
decrease GI fluid volume
Raise pH of GI content
14
Q
H2B are used for what perioperative goal?
A
reduce the risk of aspiration pneumonia
15
Q
which drug increases LES tone, speeds GI emptying, and lowers GI fluid volume?
A
Metoclopramide
16
Q
What receptor does Metoclopramide work on?
A
It enhances the stimulatory effects of Ach on intestional smooth muscle
17
Q
Which 3 drugs selectively block Serotonin 5-HT3 receptors (w/ little-no effect on Dopamine)?
A
Ondansetron, granisetron, dolasetron
18
Q
5HT3 receptors are located only centrally. True or False
A
peirpherally and centrally
19
Q
What role do 5HT3 receptors play?
A
initiation of vomiting reflex
20
Q
Class of Ketorolac?
A
parenterally administered NSAID
21
Q
How does Ketorolac provide analgesia?
A
Inhibits prostaglandin synthesis
22
Q
What drug is most selective A2 agonist?
A
Precedex
23
Q
Narcan reverses agonist activity assoicated w/ what opioid compounds?
A
endogenous and exogenous
24
Q
What is 2 parameters are considered aspiration pneumonia risk?
A
GI volume > 25 mL (0.4mL/kg) AND GI pH <2.5
25
What 8 factors palce pt aat risk for aspiration?
1. full stomach
2. intestinal obstruction
3. hiatal hernia
4. obestiy
5. pregnancy
6. reflux disease
7. emergency surgery
8. inadequate depth of anesthesia
26
What approaches are used to reduce potential aspiration
Sellick's (cricoid pressure)
| RSI
27
Do cricoid pressure and RSI eliminate pulmonary aspiration risk?
No only offer limited protection
28
How do anesthetics increase the risk of passive aspiration?
decrease LES tone
| decrease or olibterate the gag reflex
29
What areas is histamine found?
CNS, GI mucosa, other peripheral tissues
30
How is histamine synthesized?
by decarboxylation of the amino acid histidine
31
Where are histaminergic neurons lcoated?
Primarily at the posterior hypothalamus bute have wide projections int he brain
32
What role does histamine play in the sotmach?
Major role in the secretion of hydrochloric acid by parietal cells
33
Where are the highest concentration of histamine found?
Storage granules of circulating basophils and mast cells throughout the body
34
Where are mast cells concentrated?
connective tissue juste beneath epithelial(mucosal) surfaces
35
How is histamine release (degranulation) triggered from mast cells?
chemical, mechanical, or immunological sitmulation
36
How is secretion of hydrochloric acid mediated?
By gastrin-induced histamine release from enterochromaffin-like cells (ECL) in the somtach
37
What is a way that acid secretion by GI parietal cells can be increased INDIRECTLY?
By Ach via stimulation of M3
38
What is a way that acid secretion by GI parietal cells can be increased DIRECTLY?
By gastrin through an increase in intracellular Ca+ concentration
39
How do prostaglandin E2 (PGE2) inhibit acid secretion?
Decreases cAMP (cyclic adenosine monophosphate); activity
40
What receptors mediate the effects of histamine?
H1, H2, H3
41
H1 receptor moa
Activates phospholipase C
42
H2 receptor moa
increases cAMP
43
H3 receptor moa
Mediates NEGATIVE FEEDBACK, inhibiting the syntehsis and release of additional histamine
44
Where are H3 receptors primarily located?
Histamine-secreting cells
45
What does Histamine-N-methyltransferase do?
Metabolizes histamine to inactive metabolites that are excreted in URINE
46
Histamines CV affects of BP, HR, and contractility
Lowers ARTERIAL BP
Increases HR
Increases myocardial contractiliy
47
H1 receptor stimulation cardiovascular effects
increases capillary permeability and enhances VENTRICULAR IRRITABILITY
48
H2 receptor stimulation cardiovascular effects
Increases Hr and contractility
49
Both H1 and H2 stimulation CV effects
mediate peripheral arteriolar dilation and some coronary vasodilation
50
H1 stimulation respiratory effect
constricts bronchiolar smooth muscle;
| some pulmonary vasodilation
51
H2 sitmulation respiratory effects
may produce mild bronchodilation (smooth muscle)
| may be responsible for pulmonary vasoconstriction (blood vessel effect)
52
Histamines effects on pulmonary vasculature are _____.
variable
53
H2 stimulation (GI)
increases GI acid secretion
54
H1 stimulation (GI)
contraction of intestinal smooth muscle
55
The classic wheal-and-flare response of the skin to histamine results from increased ______ and _______.
capilarry permability and vasodilation
56
Dermal effect from histamine are primarily due to what receptor?
H1 activation
57
Histamine is a major mediatory of what kind of immunological reaction?
type 1 hypersensitivity reaction
58
H1 stimulation (immune)
attracts leukocytes and induces synthesis of prostaglandin
59
H2 sitmulation (immune)
activate suppressor t lymphocytes
60
Promethazine class
phenothiazine derivative w/ H1B activity as well as antidopaminergic and alpha blccking activity
61
What receptors does promethazine (phenergan) block?
H1, dopamine, alpha
62
What class is diphenhydramine?
ethanolamine
63
Uses of benadryl?
1. suppression of allergic reactions & s/s of upper resp. tract infection (uritcaria, rhinitis, conjunctivitis)
2. vertigo, n/v
3. sedation
4. cough suppression
5. dyskinesia
64
What diseases is benadryl beneficial in?
```
Menieres disease (inner ear/vertigo)
parkinsonism
```
65
H1B respiratory effect
PREVENT bronchoconstriction that occurs in reponse to histamine
66
Do H1B treat bronchial asthma?
no
67
What histamine blocker do you use to prevent the hypotensive effect of Histamien?
H1 + H2 (must be administered together)
68
Do H1 blockers affect ventilatory drive?
Unaffected in the absence of other sedatives;
| Combined with sedatives potentiates sedation
69
What antihistaminic drugs in particular have antiemetic and mild hypontic properties?
Benadryl
Promethazine
Hydroxyzine
70
What 2 antihistaminic drugs were often cmobined with opioids to potentiate analgesia?
Promethazine
| Hydroxyzine
71
Second-generateion antihistamines produce little-no sedation d/t _____.
Limited penetration of BBB
72
2nd gen antihistamines
Loratadine
Fexofenadine
Cetirizine
73
Preparations for allergic rhinitis often contain what 2 drugs?
```
antihistamines
Pseudoephedrine (vasocontrictors)
```
74
What 2 antihistamines are used primarily as antiemetic?
Meclizine
| Dimenhydrinate
75
What antihistamine is used for Cushings, carcinoid, and vascular (cluster) HA?
Cyproheptadine (also has serotonin blocking activity)
76
Usual dose of benadryl
25-50 mg (0.5-1.5 mg/kg) Q4-6H
77
H1B potentiate what other drugs?
CNS depressants such as barbiturates, Benzos, and opiods (d/t sedative effect)
78
What are 4 H2B?
Cimetidine
Famotidine
Nizatidine
Ranitidine
79
H2B MOA
Competitively inhibit histamine binding to H2 receptors
80
H2B 2 actions:
1. reduce gastric acid output
| 2. raise gastric pH
81
What is the onset of Reglan?
1-3 minutes
82
What is the normal dose of IV Reglan?
10 mg
83
Which H2B are most effective in treating Peptic, duodenal, and gastric ulcers, hypersecretory states (Zollinger-Ellison syndrome), and GERD?
ALL are EQUALLY effective
84
Duodenal and gastric ulcers are treated w/ H2B and ____.
Combo of Bismuth, Tetracycline, and Flagyl
85
What infection are duodenal and gastric ulcers associtaed w/?
Helicobacter pylori
86
What happens to the pH of Gi content after admin of H2B?
These drugs affect the pH of only those gastric secretions that occur after administration
87
How do H2B reduce the perioperative risk of aspiration pneumonia?
By decreasing gsatric fluid volume nad Hydrogen ion content
88
(for drug-induced allergic reaction) Pretreatment with combo of H1 and H2 blockers _____ histamien release
does not reduce
89
(for drug-induced allergic reaction) Pretreatment with combo of H1 and H2 blockers ______ subsequent hypotension
may decrease
90
Combo of H1 and H2 blockers provides _______ against drug-induced allergic reaction (IV contrast, blue dyes)
some protection
91
What two H2B do you want to avoid rapid IV injection?
Cimetidine and Ranitidine
92
Rapid injection of Cimetidine (particularly in critically ill) and Ranitidine can rarely cause
Hypotension
Bradycardia
Arrhythmias
Cardiac arrest
93
_____ is a H2B that can be safely injected over 2 minutes
Famotidine
94
How do H2B change the gastric flora?
By virtue of their pH effects
95
Complications of long-term Cimetidine therapy
Hepatotoxicity
Interstitial nephritis
Grnulocytopenia
Thrombocytopenia
96
Besides binding to H2 receptors, Cimetidine also binds to ____ receptors, occasionally causing ______.
Androgen
| gynecomastia and impotence
97
Which H2B causes changes in mental status ranging form lethargy and hallucinations to seizures?
Cimetidine
98
The mental status changes associated with Cimetidine adminsitration are most common in what population?
Eldelry
99
Which 3 H2B penetrate the BBB poorly?
Ranitidine
Nizatidine
Famotidine
100
When do you administer H2B as a premedication?
At bedtime and again at least 2 hours before surgery
101
How are H2B eliminated?
Kidneys
102
When do you reduce H2B dose?
With significant renal dysfunction
103
Cimetidine can cause drug interactions becuase it _____
may reduce hepatic blood flow and bind to the P450 mixed-function oxidases
104
Cimetidine can slow the metabolism of what drugs?
```
Lidocaine
Propranolol
Diazepam
Theophylline
Phenobarbital
Warfarin
Phenytoin
```
105
Which H2B is a weak inhibtior of P450?
Ranitidine
106
Which H2B does not affect P450?
Famotidine and Nizatidine
107
Antacids MOA
neutralize the acidity of gastric fluid by providing a base that reacts w/ H+ ions to form water
108
What is the base that antacids provide?
Usually Hydroxide, Carbonate, Bicarbonate, Citrate, or Trisilicate
109
Uses of antacids:
Treatment of gastric and duodenal ulcers, GERD, Zollinger-Ellison syndrome
110
What are antacids use in anesthesia?
Provide protection against the harmful affects of aspiration pneumonia by raising the pH of gastric contents
111
antacids onset
immediate (this is unlike H2B)
112
Con of antacids?
Increases intragastric volume
113
Particulate antacid examples
aluminum or magensium hydroxide
114
Aspiration of particulate antacids is comparable to waht?
the abnormalities in lung function of those that occur following acid aspiration
115
Examples of nonparticulate antacids?
sodium citrate or sodium bicarb
116
Pros of nonparticulate antacids
much less damaging to lung alveoli if aspirated
| Mix with gastric contents better
117
Usual dose of Bicitra or Polycitra
15-30 mL PO 15-20 minutes prior to induction
118
What is Bicitra
sodium citrate and citric acid
119
what is polycitra
sodium citrate, potassium citrate, and citric acid
120
Antacids alter ____ and ____ pH
gastric and urinary
121
Reglan acts peripherally as ______
cholinomimetic (ie facitilates Ach transmission at selective muscarinic receptors)
122
Reglan acts centrally as _______
dopamine receptor blocker
123
Do Reglan stimualte secretions?
No
124
Reglan's prokinetic action in the UGIT is not dependent upon _______ but is abolished by _________.
vagal innervation
antichlinergic agents
125
What 3 actions does Reglan achieve through stimulating Ach on intestinal smooth muscle?
Increases LES tone
Speeds GI emptying
Lowers gastric fluid volume
126
Reglan works on what 2 receptors
Ach/selective muscarinic
| Dopamine
127
Reglan is used for treatment of waht two things?
Diabetic gastroparesis
| GERD
128
Reglans affect on the secretion of gastric acid
None
129
Reglan's affect on teh pH of gastric fluid?
None
130
Reglan is used prophylactically to?
Decrease risk for aspiration pneumonia
131
How does Reglan produce an antiemetic effect?
Blocks dopamine receptors in the CTZ of the CNS
132
Reglan's ability to reduce PONV is _____ when given during perioperative period
negligible at these doses
133
Rapid IV admin of REglan?
Abdominal cramping
134
Reglan is CI with what patients?
Complete bowel obstruction
| Parkinsons
135
Reglan can _____ in patients with pheochromocytoma.
Induce HTN crisis by releasing catecholamines from tumor
136
Uncommon s/e of Reglan
sedation, nervousness, extrapyramidal s/s (akathisia)
137
Rare CV effects of Reglan
Low BP and arrythmias
138
Reglan increases what two hormones during short term therpay
aldosterone
| prolactin
139
Adult dose of Reglan
10-20 mg (0.25 mg/kg)
140
Route of Reglan
PO, IM, IV
141
How fast do you inject Reglan?
Over 5 minutes
142
Onset of IV Reglan
3-5 minutes
143
Onset of PO Reglant
30-60 minutes
144
How is Reglan excreted?
Urine
145
Decrease Reglan with what?
Renal dysfunction
146
What dose Reglan is used during chemo to prevent emesis?
1-2 mg/kg - Large dose
147
What medications can block the effects of Reglan?
Antimuscarinic such as Atropine and Robinul
148
What drug does Reglan decrease the absorption of?
PO Cimetidine
149
PPI examples
```
Omeprazole (Prilosec)
Lansoprazole (Prevacid)
Rabeprazole (Aciphex)
Esomeprazole (Nexium)
Pantoprazole (Protonix)
```
150
Protonix MOA
Bind to proton pump of parietal cells in the gastric mucosa and inhibit secretion of H+
151
PPI Uses:
treats: duodenal ulcer, GERD, and Zollinger-Ellison syndrome
heal: peptic ulcers and errosive GERD
152
Do PPIs or H2B heal ulcers and erosive GERD quicker?
PPIs
153
Concern when PPIs are taken with _____ drug due to inadequate ______ therapy when the drugs are combined
clopidogreal (Plavix0
antiPLT
154
Are PPIs tolerated well?
Generally, b/c they cause few s/e
155
Most common s/e of PPI
Gi system (nausea, abd. pain, constipation, diarrhea)
156
PPI rare s/e
myalgia
anaphylaxis
angioedema
severe dematologic reaction
157
Why does long-term use of PPIs increase risk of pneumonia?
bacterial colonization in the higher pH environment
158
Long-term PPI use has been associated w/ hyperplasia of the?
gastric enterochromaffin cell
159
PO doses of Omeprazole and Rabeprazole?
20 mg
160
PO dose of Protonix
40 mg
161
PO dose of Lansoprazole
15 mg
162
When do you decrease dose of PPI?
with severe liver impariement
163
How are PPIs eliminated?
liver
164
How often does PONV occur in general population (w/o prophylaxis)?
20-30%
165
How often does PONV occur in high risk (w/o prophylaxis)?
70-80%
166
As anesthetic duration increases, PONV risk _____
increases
167
WHich society provides a scoring system for PONV?
Society of Ambulatory Anesthesia (SAMBA)
168
Obesity, anxiety, and reversal of NMBD are or are not independent risk factors of PONV?
ARE NOT
169
What drugs are used in the treatment and prophylaxis of PONV?
```
5-HT3 blockers
Butyrophenones
Dexamethasone
Neurokinin-1 receptor blockers (aprepitant, Emend)
Antihistamines
Transdermal scopolamine
```
170
Risk factors for pONV (7 total)
```
female
nonsmoking
history of PONV
use of volatiles
NO
opioids
duration of surgery
```
171
Each duration of ______ of surgery increases the baseline risk of PONV by 60%.
30 minutes
172
How many PONV interventions do you do for those at moderate risk?
1-2
173
How mnay PONV interventions do you do for those at high risk?
multiple
174
Where is serotonin 5-HT present in the body?
Large quantiites in PLT and the GI tract
| NT in multiple areas of CNS
175
What part of the GIT ahs serotonin 5-HT?
enterochromaffin cells and the myenteric plexus
176
How is serotonin formed?
By hydroxylation and decarboxylation of tryptophan
177
What inactivates serotonin into 5-hydroxyindoleacetic acid (5-HIAA)?
Monoamine oxidase
178
How many receptors of serotonin are there?
At least 7, most w/ subtypes
179
What serotonin receptor mediates vomiting?
5-HT3
180
Where is the 5-HT3 receptor found?
GI tract and the brain (area postrema)
181
5-HT2a
responsilbe for smooth muscle contraction and PLT aggregation
182
5-HT4
in the GI tract and mediate secretion and peristalsis
183
5-HT6 and 5-HT7
located primarily in limbic system where they appear to pay a role in depression
184
All except ____ receptor are coupled to G proteins and affect either adenylyl cyclase or phospholipase c. (serotonin)
5-HT3
185
How are the effects of 5-HT3 mediated?
via an ion channel
186
Serotonin is a powerful ____ of arterioles and veins.
vasoconstrictor
187
What areas of the body lack serotonin's vasoconstrictive properties?
heart and skeletal muscle
188
What effect does serotonin have on the heart's vessels?
vasodilator effect, (endothelium dependent*)
189
When the myocardial endothelium is injured, serotonin produces _____.
vasoCONSTRICTION
190
What 2 vasculatures are sensitive to serotonin's arterial vasoconstrictive effect?
pulmonary and renal
191
Modest and transient _____ in cardiac contractility and HR may occur after serotonin release;reflex ____ often follows.
increases
bradycardia
192
What affect does released serotonin have on respiratory system?
contraction of smooth muscle --> increased airway resistance
| bronchoconstrictioN
193
Prominent feature associated w/ released serotonin of carcinoid syndrome?
bronchoconstriction
194
Does serotonin affect secretions?
No
195
Serotonin directly contracts GI smooth muscles via what receptor?
via 5-HT2
196
Serotonin-induced release of Ach in the myenteric plexus occurs via what receptor?
via 5-HT3
197
Serotonin 5-HT2 and 5-HT3 do what for the GI system?
greatly augement peristalsis
198
Activation of ____ serotonin receptors causes PLT aggregation.
5-HT2
199
What 3 meds selectively block 5-HT3 receptors, with no effect on dopamine receptors?
Ondansetron (Zofran)
Granisetron (Kytril)
Dolasetron (Anzemet)
200
5HT3 receptors are located peripherally in _____ and centrally at ________.
abdominal vagal afferents
CTZ of the area postrema and nucleus tractus solitarius
201
What serotonin receptor plays a roel in initiation of vomiting reflex?
5HT3
202
The 5HT3 receptors of the CTZ are ______ the BBB.
outside
203
How does the CTZ trigger zone initiate vomiting?
trigger zone is activated by substances such as ansethetics adn opioids, sends signal to neclues tractus soiatrious resulting in vomiting
204
What activates teh CTZ?
anesthestics
| opioids
205
How does the GIT stimulate PONV?
emetogenic stimuli (in a similar manner to CTZ vomiting activation)
206
When are 5HT3 administered during surgery?
at teh end of surgery
207
Zofran = 4 mg Decadron = 1.25 mg Droperidol in effectiveness of _____
antiemetic action in postop period
208
A new agent ______ has extended DOA (5HT3)
Palonsetron (Aloxi)
209
Aloxi's extended DOA is useful for what?
reducing PDNV
210
What s/e do 5HT3B have?
devoid of any serious s/e even in doses several times the recommended
211
5HT3B do not cause ____, _____, or _____.
sedation
extrapyramidal signs
respiratory depression
212
Most common s/e of 5HT3 blockers?
HA
213
5HT3 blockers ekg effect?
prolong the QT
214
Prolonged QT is more frequent with which 5HT3 blocker?
Dolasetron
215
5HT3 blockers should be used cautiously in what patients?
Those taking antiarrhythmic drugs OR those with a prolonged QT interval
216
How is Zofran metabolized?
extensive metabolism in the liver via hydroxylation and conjugation by P450
217
When should you reduce the dose of Zofran?
with liver failure
218
Recommended IV dose of Dolasetron?
12.5 mg
219
Recommended IV dose of Granisetron?
1 mg
220
What type of drug is Droperidol?
Butyrophenones
221
What is the dose of Droperidol for PONV?
0.625 - 1.25 mg
222
How does Droperidol work?
Blocks dopamine receptors that contribute to PONV developmetn
223
What medication has a black box warning about risk of QT prolongation and development of Torsades des pointes?
Droperidol
224
What dose of Droperidol causes QT prolongation and Torsades?
5-15 mg
225
With large doses of Droperidol what type of monitoring is indicated?
cardiac
226
Since Droperidol antagonizes dopamine, careful consdieration of use in ____ and _____ patients is necessary.
Parkinson's disease and patients manifesting extrapyramidal signs
227
What type of medication is prochlorperazine (Compazine)?
Phenothiazine
228
What receptors does Phenothiazine work on?
Histaminergic
Dopamine
Muscarinic
229
What is Compazine used for?
PONV management
230
What type of s/e does Compazine cause?
extrapyramidal and anticholinergic
231
Promethazine is also called?
Phenergan
232
Phenergan works primarily as ____ and ____ agent.
anticholinergic
| antihistamine
233
What s/e can happen with Phenergan?
sedation
delirium
confusion
visoin changes
234
When should you give dexamethasone (decadron) for PONV?
at induction
235
Decadron is what class?
glucocorticoid
236
Substance P is a neuropeptide that interacts with what receptors?
neurokinin-1
237
NK1 antagonists block ____ at central and peripheral receptors.
Substance P
238
What NK1 antagonist has been found to reduce PONV perioperatively?
Aprepitant (Emend)
239
What is Aprepitant an additive for?
Zofran
240
Transdermal Scopolamine can produce what s/e?
central anticholingergic
| confusion, blurred vision, dry mouth
241
Alternative methods for PONV?
acupuncture, acupressure, and transcutaneous electrical stimulation of P6 acupuncture point
242
No single agent will both TREAT and PREVENT PONV. (true or false)
True
243
Toradol classification:
parenteral NSAID that provide analgesia
244
What length of use is Toradol indicated for?
short-term <5 days
245
A standard dose of Toradol provides analgesia that = ______
6-12 mg IV morphine
246
What has a quicker onset, MOrphine or Toradol?
They have similar onset
247
What has a longer DOA, Morphine or Toradol?
Toradol
248
How long is toradols DOA?
6-8 H
249
Toradol has ____ CNS s/e.
minimal
250
Toradol dose NOT cause ____, _____, or _____.
respiratory depression
sedation
n/v
251
Does Toradol cross the BBB?
No
252
IM dose of Toradol
60 mg
253
IV dose of Toradol
30 mg loading
| then 15-30 mg Q6H
254
Who should receive a reduced dose of Toradol?
Elderly patients
255
What decreases the protein binding of Toradol; thereby increasing active unbound drug?
Aspirin
256
Toradol's effect on MAC?
none
257
Toradols effect on hemodynamics?
none
258
Toradol decreases the requirement of _____
postoperative analgesics.
259
What do NSAIDs inhibit?
cyclooxygenase (COX) isoenzymes
260
What 2 things does COX-1 do?
Maintains gastric mucosa
| Stimulates PLT aggregation
261
What does COX-2 do?
Expressed during inflammation
262
Toradol is a ______ inhibitor of COX ______
nonselective
| 1 & 2
263
What NSAIDs are selective for COX-2?
Parecoxib (Dynastat)
Celecoxib (Celebrex)
Rofecoxib (Vioxx)
264
NSAIDs selective for COX ___ have an increased risk of CV thromboembolic events.
2
265
When are NSAIDs that either selectively or nonselectively inhibit COX-2 contraindicated?
post CABG
266
IV Tylonel is called?
Ofirmev
267
Acetaminophen class:
Centrally acting analgesic w/ likley central COX inhibition and weak peripheral COX
268
Acetaminophen lacks _____ b/c of its moa
GI irritation and clotting abnormalities
269
Max dose of Ofirmev for >50kg
1 g
270
Max daily dose of Ofirmev for >50 kg
4 g
271
Max dose of Ofirmev for <50 kg
15 mg/kg
272
Max daily dose of Ofirmev for <50 kg
75 mg/kg/day
273
Ofirmev should be used in caution in what patients?
Hepatic disease or undergoing hepatic surgery
274
Clonidine is _____ lipid soluble
highly
275
Can Clonidine penetrate the BBB and placenta?
Yes
276
Clonidine class
Alpha 2 agonist
277
WHere is the binding of Clonidine to receptors highest?
The rostral ventrolateral medulla in the brainstem (the final common path for sympethetic outflow)
278
Clonidine activates what type of neurons?
inhibitory
279
Clonidines overal effect is to ____, ____, and ____.
decrease sympathetic activity
enhance parasypmathetic tone
reduce circulating catecholamines
280
There is evidence that Clonidine's antiHTN effect is b/c of its binding to _____ receptor.
nonadrenergic (imidazoline)
281
CLonidine's analgesic effect is mediated how? (particularly in spinal cord)
entirely via pre and post synpatic alpha 2 receptors that block nociceptive transmission
282
Clonidine has what effect when applied to peripheral nerves?
LA
283
Clonidine is added to what kind of solutions often?
LA
284
```
Clonidine CV effects:
___ sympathetic tone
____ SVR
____ HR
_____ BP
```
↓ALL
285
CLonidine is used as an adjunct for ___, ___, and ____ in anesthesia
epidural
caudal
peripheral nerve block
286
CLonidine is often used in the management of what issue?
chronic neuropathic pain
287
When given epidurally, Cloidine's analgesic effect is ____.
segmental (localized to lvel at which it is infused)
288
When added to LA with ____ DOA for epidural or peripheral nerve block, Clonidine will _____.
intermediate;
| markedly prolong DOA
289
LA with intermediate DOA
Mepivacaine or Lidociane
290
Common s/e of clonidine
sedation
dizzy
bradycardia
dry mouth
291
Rare s/e of clonidine
bradycardia
orthostatic hypotension
nausea
diarrhea
292
Abrupt d/c of Clonidine following adminsitration >____, leads to rebound hypertension, agitation, and sympathetic overacitvity.
1 month
293
Epidural clonidine starting dose
30 mcg/h
294
PO clonidine maintenence dose
0.1 mg - 0.3 mg bid
295
PO clonidine onset
30-60 minutes
296
DOA PO clonidine
6-12 h
297
Doses of Clonidine for acute HTN
0.1 mg Q1H (max 0.6 mg)
298
Transdermal dose of Clonidine
0.1, 0.2, 0.3 mg (replaced Q7D)
299
How is clonidine metabolzied?
liver
300
How is clonidine excreted?
renal
301
Doses of clonidine should be reduced with what patients?
renal insufficiency
302
Clonidine prolongs ___ and ____ block from LA
sensroy and motor
303
Clonidine can potentiate sedaiton, hypotension, and bradycardia when given with?
hypnotic agents
general anesthetics
sedatives
304
You should use clonidine cautiously if at all in patients that take what medication?
BB
| also caution /w cardiac conduction issues
305
Clonidine's effect on diabetics
masks hypoglycemia
306
Precedex class
parenteral selective A2 agonist
307
Which medication is more selective for A2?
precedex
308
At high doses, precedex loses _____ and also stimualtes ____.
selectivitiy
| A1
309
Precedex actions:
sedation
anxiolysis
analgesia
blunts sympathetic response to surgery
310
Precedex has a ____ sparing effect
opiod
311
Does precedex significantly depress respiratory drive?
no
312
Does precedex cause excessive sedation?
no
313
Does precedex cause airway obstruction?
it can
314
How long is precedex used for mechanical ventilation?
short term <24H
315
D/c of precedex is used longer than 24H can cause what?
withdrawal
316
4 s/e of precedex
bradycardia
heart block
hypotension
nausea
317
Precedex loading dose
1 mcg/kg over 10 min
318
precedex maintaine gtt
0.2-0.7 mcg/kg/h
319
Precedex onset
rapid
320
Precedex half life
2 hours
321
How is Precedex metabolized?
liver
322
How is Precedex excreted?
Urine
323
When should you reduce Precedex doses?
Renal or liver impairement
324
You should be cautious administering precedex with ____, ____, or ____ drugs
vasodilators
cardiac depressants
drugs that lower HR
325
Doxapram (Dopram) class
peripheral and CNS stimulant
326
Low doses of Doxapram stimulate ____.
hypoxic drive
327
Low doses of Doxapram increase ____ and ____.
tidal volume
| RR
328
Large doses of Doxapram stimualte ____.
the central respiratory centers in the medulla
329
Low doses of Doxapram are selective for activation of what?
carotid chemoreceptors
330
What does Doxapram mimic?
Low PaO2
331
What drug is useful in COPD patients who are dpendent on hypoxic drive yet require supplemental oxygen?
Doxapram
332
Doxapram can temporarily overcome ___ and _____
drug-induced respiratory and CNS depression
333
Doxapram s/e
changes in mental status
cardiac abnormalities
pulmonary dysfunction
(remember its a STIMULANT)
334
What is a particular concern for patients administered Doxapram during the postoperative period?
Laryngospasm
| Vomiting
335
Doxapram CI (6)
1. epilepsy
2. cerrebrovascular disease
3. acute head injury
4. CAD
5. HTN
6. broncial asthma
336
Doxapram bolus IV dose
0.5-1 mg/kg
337
Bolus Doxapram onset
1 minute
338
Bolus Doxapram DOA
5-12 minutes
339
Doxapram Gtt dose
1-3 mg/min (max 4 mg/kg)
340
Name 2 endogenous opioid compounds?
enkephalins
| endorphins
341
Perioperative resp. depression d/t opioids can be antagonized in ____w/ Narcan adminsitration.
1-2 minutes
342
With minimum required dose of Narcan that maintains adequate ventilation, what can be spared?
some degree of analgesia
343
Low doses of IV Narcan reverse the s/e of ______ without necesarily reversing ____.
epidural opioids
| analgesia
344
```
Abrupt reversal w/ Narcan can cause
1.
2.
3.
4.
```
1. tachycardia
2. ventricular irritability
3. HTN
4. pulmonary edema
345
The extent of Narcan's s/e is proportional to ____ and ___.
amount of opioid being reversed
| speed of reversal
346
What is a pure opioid antagonist w/ high affinity for Mu receptor, but which has longer half life than Narcan?
Naltrexone
347
PO Naltrexone use:
maintenance treatment of opioid addicts and ethanol abuse (blocks pleasnat effects)
348
Other name for Flumazenil?
Romazicon
349
Flumazenil class:
specific and competative antagonist of benzos at benzo receptor
350
Flumazenil onset
<1 minute
351
Flumazenil reverses the ____ effect of Benzos, but less relaibliy prevents _____
hypnotic; amnesia
352
What can linger after flumazenil use?
evidence of repsiratory depression (despite AAO)
353
TV and minute ventilation _____, while the slop of carbon dioxide is ____ with Flumazenil use?
normal; depressed
354
Benzo reversal with Flumazenil is most difficult to reverse in what patients?
elderly
355
Rapid admin of flumazenil?
anxiety or withdrawl
356
Administration of what reversal has been associated with increased in ICP in patients with head injury and abnormal intracranial compliance?
Flumazenil
357
When might Flumazenil cause seizures?
If benzos were given as anticonvulsant or w/ OD of TCAs
358
What 2 drugs may increase the incidence of emergency dysphoria and hallucinations with flumazenil reversal?
Midazolam -Ketamine combo
359
Does flumazenil cause n/v?
yes, not uncommon
360
Does flumazenil affect MAC?
no
361
Flumazenil dose:
0.2 mg/min until desired reversal reached
362
Usual total dose of flumazenil?
0.6-1 mg
363
How is flumazenil cleared?
hepatic
364
When are repeat doses of flumazenil required?
may be required after 1-2 H to avoid resedation
365
With an OD of long acting Benzos, what should be considered upon reversal?
Gtt (0.5mg/h) of Flumazenil may be preferred
366
What can prolong the clearance of Benzos and Flumazenil?
Liver failure
367
LA transiently inhibit some or all of ____, ____, or ____ function.
sensory
motor
autonomic nerve
368
Local and regional anesthesia techniques depend on what?
LA
369
What is the resting membrane potential of nuerons?
-60 to -70
370
The sodium-potassium pump sends ___ Na ____ and ___K ___.
3 Na out
| 2 K in
371
The cell membrane is more leaky for which electrolyte?
K
372
What is the Na channel made up of?
1 large alpha subunit
| 1-2 smaller beta subunits
373
Where does the Na ion pass?
alpha subunit
374
What three states do Na channels exist in?
1. resting
2. open
3. inactivated
375
Where do LA bind on the Na channel?
alpha subunit
376
LA consist of what 2 groups?
lipophilic and hydrophilic
377
The lipophilic group of a LA is usually what?
aromatic benzene ring
378
The hydrophilic group of LA is usually waht?
tertiary amine
379
What determines the class of LA
the nature of the intermediate chain
380
What are the two type sof LA?
ester
| amides
381
Potency of LA correlates w/ the ability of the LA to _____.
permeate lipid membranes
382
How can you increase potency of LA?
adding large alkyl groups to parent molecule
383
What affects the minimum concentration of LA that blocks impulse? (5 things)
1. fiber size
2. myelination
3. pH
4. stimulation frequency
5. electrolyte concentratoin
384
The onset of LA depends on?
1.
2.
3.
1. lipid solublity
2. concentration of nonionized/more lipid soluble free base to ionized/water soluble form
3. pKa
385
LA are prepared commerically as ______.
water soluble hydrocholirde salts
386
Epinephrine is stable or unstable in alkaline environements?
unstable
387
Commercial products that contain Epi are generally more ____ than plain solutions. (acidic or basic)
acidic
388
What is the pH of water soluble hydrochloride salt LA?
6-7
389
DOA of LA correlates w/ ____ and ____.
potency
| lipid solubility
390
What is the benefit of alkalyzing LA?
speeds onset
| improves qulaity of block
391
LA are weak ___.
bases
392
Acid + acid =
nonionized
393
base + base =
nonionized
394
acid + base +
ionized
395
pKa is?
pH were 50% nonionzed and 50% ionized
396
pKA affects waht?
onset
397
Lipid solublity affects what?
potency
398
The ___ lipid soluble the ___ potent.
more; more
399
Why does lipid solublity affect potency?
The more lipid soluble, the less likely blood flow can carry LA away.
400
protein binding affects what?
DOA of LA
401
A Na channel that is in the resting/closed stage, the M-gate is open or closed?
closed
402
In a Na channel in the activated/open stage, the M-gate and H-gate are open or closed?
open
403
In a Na channel in the inactivated state, what gate is closed rendering its inactivation?
H-gate
404
What gate does the LA interact with to cause its affect?
H-gate
405
A LA must have a ___ charge to interact with the H-gate.
postive
406
Can ionized or nonionzed cross the phospholipid layer?
nonionzied
407
Can ionized or nonionzed bind with the h-gate inside the membrane?
ionized
408
Which is lipid soluble: non-ionized or ionized?
non-ionized
409
Which is water soluble: non-ionzed or ionzied?
ionized
410
Which is the acid form: noin-ionzied or ionzied?
non-ionized
411
which is the conjugate base form: nonionized or ionized?
ionzied
412
What happens if a largely non-ionized form of a drug is place in water?
precipitates
413
What 2 things delay LA onset?
1. drug that has a pKa further from physiologic pH
| 2. pH of environment that is acidic
414
What type of environments are acidic?
wound infections or ischemic areas
415
Which a drug that has a pKa far from the physiologic pH, more of the drug is nonionized or ionzied?
ionized
416
More protein bound = _____ DOA
longer
417
When the pKa is closer to the physiologic pH, the onset is faster or slower?
faster
418
What is the pKa of chloroprociane?
9.1
419
What drug is the exception to the pKa and onset rule?
Chloroprociane
420
How much of Chloroprociane is protein bound?
0%
421
What is the pKa of prociane?
9.1
422
What is the protein binding of Procaine?
o%
423
What is the pKa of Lidocaine?
7.6-7.9
424
What is Lidocianes onset?
"relatively fast"
425
What is added to LA to prolong duration?
Epi
426
What is added to LA for faster onset?
Bicarb
427
Why do you add Bicarb to speed up onset?
The drug is more nonionzed w/ Bicarb. (LA are weak bases )
428
What medication can precipitate when you add Bicarb?
Bupivacaine
429
What dose of Bicarb do you add to Bupivacaine?
0.1 mEq per 20 mL (SMALLER than normal)
430
What does of Bicarb do you add to Lidocaine?
1 mEq Bicarb/ 10 mL of Lidocaine
431
Epi will not increase the DOA for what drugs and why?
B, E, R
| b/c they have long DOA already
432
What is the pKa range of LA?
7.6 - 9.1
433
Why is the speed of onset slower when a LA is injected into an infected area?
The area is acidic and the extent of ionized portion will be increased. Then diffusion will be slowed
434
The greater the amount of LA that exists in ___ state, the faster the onset.
nonionized
435
Short acting LA?
Pro
| C
436
Intermediate acting LA?
L, M, Pri
437
Long Acting LA?
BET on a long shot
438
LA w/ high pKa are highly ___ at physiologic pH
ionized
439
For LA w/ high pKa the Na channel must be in the ____ state for effect to occur.
open (activated)
440
What nerves have greater suspectiblity to LA w/ high pKa?
nerves w/ frequent depolarizations
441
What nerves have frequent depolarizations?
sensory nerves, autonomic nerves
442
What nerves have less freuqnet depolarizatoins?
motor nerves
443
Which nerves have less susceptibility to LA w/ high pKa?
motor nerves (b/c less frequent depolarizations)
444
Where does sympathetic block occur?
2-6 dermatones higher than sensory block
445
where does motor block occur?
2 dermatones lower than sensroy block
446
How does the LA progress in block?
1. autonomic, temp, pain (ATP)
2. touch, pressure (TP)
3. motor, vibratory, proprioception (MVP)
447
How many nodes of Ravier must be blocked to stop nerve conduction of myelinated axons?
2-3
448
What do weak acids combine with?
postive charge ions (Na, Mg, Ca)
449
What do weak bases combine with?
negative charged ions (cl, sulfate)
450
Which drugs are examples of weak acids?
Sodium Ceto
| Magnesium Tibucaine
451
Which drug is an example of a weak base?
Lidocaine hydrochloride
452
Weak acids administered to a pt with a pH of 1 (lol) is more nonionized or ionized?
nonionized
453
Weak acids administered to a pt w/ a pH of 14 is more nonionied or ionized?
ionized
454
WEak bases adminsitered toa pt w/ a pH of 1 (lol), the drug is more nonionized or ionized?
ionized
455
Weak bases administered toa. pt w/ a pH of 14, teh drug is more nonionized or ionized?
nonionized
456
Weak bases become more ____ as pH increases
nonionized
457
Should a weak acid be stored in a low or high pH?
High so it does not precipitate
458
What has contributed to the emergence of bacterial resistance?
Excessive treatment to treat condition that benefit little or not at all
459
What percentage of Rx written, is written for conditions for which Rx are rarely indicated in ambulatory patients?
25%
460
What are some conditions that have little benefit from Rx?
URI
| Bronchitis
461
What is the surgical care improvement project (SCIP)?
designed to combat a perceived national crisis of preventable surgical site infections identified in 1990s
462
Surgical site infection are associated w/ what 3 things:
1. double risk of mortality
2. 60% higher likelihood of spending time in ICU
3. 5x risk of readmission
463
SIP was expanded to SCIP to include ____?
additional perioperative qulatiy measures r/t infection control
464
SCIP has been retired. T/F
T
465
Under joint commission, not every surgical infection is targeted now, wht is targeted?
Hospitals are allowed to choose targeted surgical site infections based on own risk assessments
466
Risk factors for infection?
```
1. extremes of age
poor nutrition
obestiy
DM *
Periop glycemic control
PVD
tobacco use
coexistent infections
altered immune response
corticosteroid therapy **
```
467
Other risk factors of surgical infection?
```
surgical scrub/hair removal
surgical experience of surgeon
technique (open vs/ lap)
duration of surgery
sterilizaiton of instruments
maintenance of normothermia
```
468
SCIP findins show for bowel surgeries, BS should be kept < ____ for ____ hours post-op b/c there is evidence showing significantly lower number of surgical site infection.
200
| 48
469
What favors infection and imparied healing?
Issues r/t hypothermia
470
What issues are r/t hypothermia?
1. results in peripheral vasoconstriction
2. decreased wound oxygen tension
3. decreased recruitment of leukocytes
471
Method to prevent normothermia associated infections?
intraoperative warming
472
What is the difference between SCIP 1 and 2?
1: prophylactic abx received within 1h prior to incision
2: prophylactic abx selection for each patient
473
With Scip 2, the Abx should be appropraite to waht 2 things?
1. most likley microorganisms r/t procedure
| 2. patient characteristics
474
Abx should be given on ___ vs ____
risk
| benefit
475
When does the risk of using Abx outweigh the benefits?
in clean elective surgical procedures
476
example of clean elective surgical procedure
mastectomy or thyroidectomy where tissue (other than skin) carrying an indigenous flora is being penetrated
477
What are the predominant organisms causing surgical site infection after clean procedures are?
skin flor
478
skin flora organisms?
Staph aureus
| Staph epidermidis
479
Cephalosporings have ___ TI
wide
480
Cephalosporins have high or low incidence of s/e?
low
481
What cephalosporins are used most often?
cost effective first generations
482
Example of 1st gen cephalosporin?
cefazolin
483
What is the abx of choice for surgical procedure where normal flora, skin flora, GI and GU tracts are the most likely pathogens?
CEPHALOSPORINS
484
How common are documented IgE reactions to cephalosporin?
rare
485
Most reactions to cephalosporin are d/t?
mistaken allergies r/t n/v, yeast infection
486
Can you use cephalosporins in pts who are allergic to PNC?
YES***
487
A PNC reaction cannot be an IgE-mediated reaction such as these 4 things?
```
1. anaphylaxis
urticaria
bronchospams
exfoliative dermatitis (SJS)
DO NOT GIVE CEPHALOSPORINS EITHER
```
488
Early reports of high cross-ractivity of PCN and ceph was r/t what?
contaminated drug lots
489
What is the cross-reactivity rate of ceph and pnc?
1%
490
True anaphylaxis w/ ceph is severe. T/F
TRUE!
491
Does bowel prep alone reduce infection?
No
492
What was used to eradicate gram neg organisms, S. aureus, and yeasts from oral cavity to rectum?
selective decontamination of digestive tract w/ oral topical polymiyxin, tobramycin, and amphotericin
493
Why can you not use Vanc w/ bowel prep and decontamination?
it would be active against MRSA BUT also would affect gram positive flora which plays an important role in resistance to colonization
494
What is a nosocomial infection?
hospital acquired
495
What 3 sites do nearly 80% of NI occur?
1. urinary tract
2. respiratory tract
3. blood stream
496
NI are associated highly w/ what 3 things?
1. ventilators
2. vascular access catheters
3. urinary catheters
497
Vascular access catheters are most common cause of what 2?
bacteremia
| fungemia
498
In the CT surgery population, ____ is associated w/ an approx. 50% decrease in deep sternal infection.
glucose control
499
CT surgery population - glucose control best method for reduction in surgical site infection?
continuous insulin gtt (when compared w/ SQ injection)
500
Stopping smoking briefly prior to surgery decreases what rates by about 50%?
infection
501
When do you stop smoking preop?
4-8 weeks prior
502
Immunosuppresion from long term use of corticosteroids has been considered a risk factor for surigcal site infection. T/F
Few studies support this claim
503
Long term steroid use is associated w/ _____ in bowel surgeries.
anatomotic leaks
504
Does 1 time use of corticosteroid for n/v and pain lead to infection?
no
505
When do IgE mediated anaphlyatic raction to antimicrobials occur?
30-60 min after dosing
506
IgE mediated anaphylactic reaction to antimicrobials s/s:
urticaria (hives)
bronchospasm
Hemodynamic collapse
507
Examples of clean-contaminated procedures
colorectal and abdominal surgeries
508
Clean contaminated procedures require additional coverage for what?
gram-neg rods and anaerobes in addition to skin flora
509
What can be added for additional coverage of gram-neg rods and anareobes for clean-contaminated procedures?
Metronidazole
510
Metronidazole is usually added with what abx?
1. cefazolin
2. cefoxitin
3. cefotetan
4. ampicillin-sulbactam
5. ertapenem
6. ceftriaxone
511
What 2 types of abx are bactericidial?
PCN
| Cephalosporin
512
Methods for sterilizing instruments? (6 total)
```
Formaldehyde
Glutaraldehyde
Pasteruzaiton
cresol
silver nitrate
ethylene oxide
```
513
In clean contaminated procedures, the most common organisms include:
gram negative rods
Enterococci
staph aureus
staph epidermidis
