Final Exam Review Flashcards
(364 cards)
1
Q
Should you plug electrical devices into the back of the anesthesia machine?
A
No, never!
2
Q
What are the 3 pressure systems in the anesthesia machine?
A
- High pressure (think back of the machine)
- Intermediate pressure (machine itself)
- Low pressure (connections to patient)
3
Q
Pressure ranges for high pressure system
A
750-2200 psi
4
Q
Pressure ranges for intermediate pressure system
A
40-50 psi
5
Q
Pressure ranges for low pressure system
A
16 psi
6
Q
Cylinders/hanger yoke are part of the ___ pressure system
A
High
7
Q
O2 flush valve is part of the ___ pressure system
A
Intermediate
8
Q
Vaporizers are part of the ___ pressure system
A
Low
9
Q
Cylinders should be left in the ___ position
A
Off—reserve for emergency use only
10
Q
Oxygen cylinder color, PSI, and E-cylinder capacity
A
Green, 1900-2200 psi, 660 capacity
11
Q
Nitrous oxide cylinder color, PSI, and E-cylinder capacity
A
Blue, 745 PSI, 1600 capacity
12
Q
Air cylinder color, PSI, and E-cylinder capacity
A
Yellow, 1800 PSI, 600 capacity
13
Q
Pin index safety system (PISS) is meant to prevent ___
A
Misconnections of cylinders
14
Q
Oxygen pin index on the yoke =
A
2,5
15
Q
Nitrous oxide pin index on the yoke =
A
3,5
16
Q
___ orients the cylinders
A
Hanger yoke
17
Q
What is the most fragile part of the anesthesia machine?
A
Cylinder valve
18
Q
Oxygen in the pipeline is supplied at ___
A
50 psi
19
Q
What happens if oxygen pressure is lost?
A
Oxygen low-pressure alarm sounds; fail-safe valves stop delivery of other gases
20
Q
What should you do if the oxygen pipeline supply fails?
A
Use backup oxygen cylinder, disconnect pipeline supply, use low flow O2, turn off vent, bag patient manually…do NOT reconnect pipeline supply until it has been tested
21
Q
What are three valves on the anesthesia gas machine?
A
- Free-floating valve
- Ball and spring valve
- Diaphragm valve
22
Q
Which type of valve moves in the direction or push of gas flow; prevents gas from leaking out of the system; and prevents the emptying of gases into an empty cylinder or from wall oxygen coming into a cylinder (“safety” valve)?
A
Free-floating valve
23
Q
Failure to open the cylinder valve on the free-floating valve results in ___ to the anesthesia machine
A
No gas flow
24
Q
Which type of valve prevents mixing of nitrous oxide and oxygen and contains the oxygen fail-safe device?
A
Ball and spring valve
25
The oxygen fail-safe device will turn off the flow of other gases (i.e.: nitrous oxide) if the oxygen pressure falls below ___
25 psi
26
What type of valve is the oxygen flush valve?
Ball and spring valve
27
How much oxygen (L/min) flushes through the oxygen flush valve?
35-75 L/min
28
What type of valve reduces pressure in the system?
Diaphragm valve
29
What are two types of diaphragm valves?
- First stage regulator
| - Second stage regulator
30
First stage regulator reduces pressure to ___ psi
40-50 psi (intermediate pressure)
31
Second stage regulator reduces pressure from ___ psi to ___ psi
40-50 psi to 16 psi (intermediate to low pressure)
32
Should you use a vaporizer if it tips over?
NO!!! More liquid vapor will get into the chamber and carry more agent to the patient (can be a lethal dose)...DO NOT USE
33
What type of breathing system do we use?
Semi-closed system—patient hooked up to anesthesia machine; anesthetic gas remains in system, no room air inspired, expired air exits through scavenging system
34
What color does soda lime turn when exhausted?
Purple
35
What inhalation agent generates compound A when degraded?
Sevo
36
What are HMEs?
Heat and moisture exchangers—retain heat and moisture in anesthesia circuit; effective bacterial/viral filters
37
HMEs increase ___ and ___
Dead space and work of breathing
38
What can occur if HME becomes blocked?
Obstruction
39
Two types of HMEs?
Hydrophobic and hygroscopic
40
What are two types of bellows in the AGM?
- Ascending
| - Descending
41
Ascending bellows ___ on expiration
Ascends
42
Descending bellows ___ on expiration
Descends
43
Which bellows is safer?
Ascending—will not fill if disconnect occurs; descending bellows will continue upward/downward motion despite disconnect (must have CO2/apnea alarm)
44
4 ventilator modes:
- Volume control
- Pressure control
- Synchronized intermittent mandatory ventilation
- Pressure support
45
Volume control—constant ___ delivered per breath
Tidal volume
46
Pressure control—constant ___ with each breath
Inspiratory pressure
47
Synchronized intermittent mandatory ventilation—preset ___
Respiratory rate
48
Pressure support—adds preset ___ during inspiration, can also provide a preset ___
Pressure, PEEP
49
What are 3 single cartilages in the airway?
- Epiglottis
- Thyroid
- Cricothyroid
50
What are 3 paired cartilages in the airway?
- Arytenoid
- Corniculate
- Cuneiform
51
What is the only full ring of the trachea?
Cricoid ring
52
What is the thryomental distance?
Measure from upper edge of thyroid cartilage to chin with the head fully extended
Should be 2 fingers
53
A short thyromental distance =
An anterior larynx, not an easy intubation
54
Thyromental distance > 7 cm =
Easy intubation
55
Thryomental distance < 6 cm =
Difficult airway
56
Mallampati-Class 1
Tonsillar pillars/fauces, uvula, soft palate
57
Mallampati-Class 2
Tonsillar fauces ONLY, uvula, soft palate
58
Mallampati-Class 3
Soft palate
59
Mallampati-Class 4
Hard palate only
60
What is the normal A-O (Atlanto-occipital) angle?
35 degrees
61
How does having no teeth affect mask ventilation vs. intubation?
Difficult mask ventilation, easy intubation
62
Cormack/Lehane View-Grade 1
Full view of epiglottis, glottic opening, and vocal cords
63
Cormack/Lehane View-Class 2
Partial view of epiglottis and vocal cords
64
Cormack/Lehane View-Grade 3
Epiglottis only
65
Cormack/Lehane View-Grade 4
Soft palate only
66
Amount of air to inject in LMAs
10 x the size of the LMA minus 10
67
LMA size 3
20 ccs, for children 30-50 kg
68
LMA size 4
30 ccs, adults 50-70 kg
69
LMA size 5
40 ccs, adults 70-100 kg
70
LMA size 6
50 ccs, adults over 100 kg
71
Obtain ___ when doing a spinal or epidural and patient has a history of taking anticoagulants
Coagulation screen
72
How do seizure disorders affect MAC?
Increase MAC value—patient may require higher doses of meds d/t seizure meds being CYP inducers
73
What should you do if a patient has pre-existing nerve injuries?
Document them!
74
What are METs?
How we can assess a patient’s CV function—exercise tolerance in metabolic equivalents
75
We want at least ___ METs
4 = good functional capacity
Examples:
- Light/heavy housework
- Climbing a flight of stairs without stopping
- Walking or running a short distance
- Moderate recreational activities
76
Want to maintain patient within ___ of their baseline BP
20%
77
Should wait at least ___ days after an MI for elective surgery
60 days
78
What puts a patient at greatest risk for non-cardiac surgery MI?
Aortic stenosis
79
Always want patient to continue taking their scheduled ___
Beta-blocker—if they didn’t take it, have to give beta-blocker pre- or intraoperatively to reduce the risk of perioperative ischemia
80
Risk of ___ increases as surgical site approaches the diaphragm
Pulmonary complications
81
Length of surgery > ___ increases risk for pulmonary complications
2-3 hours
82
Patients with OSA have difficult with ___
Mask ventilation
83
Risk for ___ in patients with asthma—be prepared
Bronchospasm
84
STOP-BANG questionnaire assesses what?
OSA risk
85
STOP-BANG stands for...
```
S-Snore loudly?
T-Tired during daytime?
O-Observed not breathing when asleep?
P-blood Pressure high?
B-BMI > 35
A-Age greater than 50
N-Neck circumference greater than 40
G-Gender = male?
```
86
Chest x-ray pre-op only if active ___, ___ surgery, age > ___
Active chest disease, intrathoracic surgery, age > 60
87
High risk for ___ in SBO
Aspiration—RSI intubation, Sellick’s maneuver (cricoid pressure)
88
Previous gastric bypass = NO ___
NGT
89
Active or uncontrolled GERD = NO ___
LMA
90
Aspiration pneumonia is AKA ___
Mendelson syndrome
91
Fasting guidelines before surgery—no ___ or ___ after midnight
Chewing gum or candy
92
Fasting guidelines—clear liquids up to ___ hours before surgery
2 hours
93
Fasting guidelines—breast milk up to ___ hours before surgery
4 hours
94
Fasting guidelines—no infant formula, nonhuman milk, or light meal for at least ___ hours before surgery
6 hours
95
Fasting guidelines—prescribed medications can be administered with ___ ml water for adults (up to ___ ml for children) up to ___ hour before anesthesia
150 ml; 75 ml; 1 hour before
96
For total joint procedures, always check ___ during procedure, regardless if patient is diabetic or not
Blood glucose
97
If patient is taking metformin, when should they stop taking it before surgery and why?
Stop taking 48 hours prior to surgery d/t risk for renal impairments
98
If patient is on insulin, take ___ or ___ of dose morning of surgery
1/4 or 1/2 dose
99
What is goal for patients who are hyperthyroid before surgery?
Get them euthyroid!
Anti thyroid meds for 6-8 weeks pre-op, followed by iodine for 1-2 weeks pre-op
100
May need to use what medication intraoperatively for patients who are hyperthyroid?
Beta-blockers—usually propanolol
101
What about patients who are hypothyroid and having surgery?
No recommendations
102
If patient is on long-term steroids, they may need ___ for the procedure
Stress dose steroids
103
Acute alcohol intoxication ___ anesthetic requirements
LOWERS
104
Alcohol withdrawal ___ anesthetic requirements
INCREASES
105
Avoid ___ in cocaine users
Beta blockers! Will have unopposed alpha stimulation—accelerated HTN
106
What type of medication should you use in cocaine users instead of beta blockers?
Calcium channel blockers to manage tachycardia/HTN
107
What medication is the most common cause of intraoperative allergic reaction?
Rocuronium
108
ASA Class I
Healthy patient
109
ASA Class V
Surgery is a last effort in this patient—i.e.: PE, uncontrolled hemorrhage from AAA, head injury with increased ICP
110
ASA Class VI
Declared brain dead patient donating organ
111
What ASA Class is this? — mild to moderate systemic disease—i.e.: essential HTN, diabetes, chronic bronchitis, anemia, morbid obesity, age extremes
ASA Class II
112
What ASA Class is this? — severe systemic disease that limits activity—i.e.: poorly controlled HTN, DM with vascular complications, angina pectoris, history of previous MI
ASA Class III
113
What ASA Class is this? — severe systemic disease that is constantly life threatening (i.e.: CHF, persistent angina, advanced pulmonary, renal, or hepatic dysfunction)
ASA Class IV
114
Failure to obtain consent = breach of ___
Duty
115
Performing a procedure without proper consent = ___
Battery
116
Anesthesia can proceed without consent in emergencies—doctrine of ___
Doctrine of implied consent
117
SOAPM for all anesthetics
```
S-suction
O-oxygen
A-airway supplies
P-positive pressure/pharmacy
M-monitors/medications
```
118
Standard I =
Perform pre-operative assessment
119
Standard II =
Obtain informed consent
120
Standard III =
Form patient-specific anesthesia care plan
121
What are 2 contraindications for esophageal stethoscope?
- Esophageal varices/strictures
| - History of bariatric surgery
122
Red light = ___ nm, ___
660 nm, deoxyhemoglobin
123
Infrared light = ___ nm, ___
940 nm, oxyhemoglobin
124
What Law is the basis for pulse oximetry?
Beer Lambert’s Law
125
ETCO2 is ___ mm Hg (higher/lower) than PaCO2 on ABG
2-5 mm Hg LOWER
126
D point on ETCO2 waveform =
End tidal measurement
127
Normal PR interval =
0.12-0.2 sec
128
Normal QRS
0.06-0.10 sec
129
Normal QT interval
< 500
130
How do anesthetics affect thermoregulation?
Inhibit central thermoregulation by interfering with hypothalamic function
131
How can you tell if patient is spontaneously breathing based on ETCO2 waveform?
Curare cleft
132
Low pressure alarm =
Disconnect, leak
133
High pressure alarm =
Kink, mucus plug
134
High pressure alarm is usually set at ___
40
135
Is EKG a measure of heart function?
NO
136
Stimulation of ulnar nerve = contraction of ___
Adductor pollicis muscle
137
Stimulation of facial nerve = contraction of ___
Orbicularis oculi
138
Which muscle recovers faster from neuromuscular blockage—adductor pollicis or orbicularis oculi?
Orbicularis oculi
139
You don’t lose twitches until ___% of muscles are blocked
70%
140
4/4 twitches =
70% paralyzed
141
3/4 twitches =
75-80% paralyzed
142
2/4 twitches =
80-85% paralyzed
143
1/4 twitches =
90-95% paralyzed
144
0/4 twitches =
100% paralyzed
145
Only thing that will NOT affect pulse ox reading is ___
Fetal hemoglobin
146
Succinylcholine =
Depolarizing agent, does NOT cause fade, causes fasiculations
147
Non-depolarizing agents cause ___
Fade (i.e.: rocuronium, vecuronium, pancuronium)
148
TOF =
2 Hz for 2 seconds, every 0.5 seconds
149
Double burst =
50 Hz, 2 short bursts, every 0.75 seconds
150
Tetany =
50 or 100 Hz for 5 seconds
151
Which twitch monitoring method is used to see if patient is on their way to waking up?
Tetany
152
Will see ___ with tetany if non-depolarizing blocking agents are used
Fade
153
___ provides early evidence of ischemia intraoperatively
EEG
154
Goal is to titrate concentrations of anesthesia to maintain BIS near ___
60
155
Light moderate sedation = BIS ___
80
156
BIS < 60 =
Unresponsive
157
What monitor should you use during carotid surgery to monitor oxygen levels?
Cerebral oximetry monitor
158
What alters evoked potentials?
General anesthesia
159
What are 4 types of evoked potentials?
- Visual
- Auditory
- Somatosensory
- Motor
160
Perioperative mortality = death that occurs within ___ days after surgery
2-30 days
161
Top 3 ASA closed claims:
- Death
- Nerve injury
- Brain damage
162
3 emerging claim areas:
- Regional
- Chronic pain management
- Acute pain
163
What is the most common airway injury from anesthesia?
Dental injury
164
What can contribute to peripheral nerve injury?
Positioning
165
How can you prevent corneal abrasion?
Tape/lubricate eye
166
How can you prevent retinal ischemia when prone?
Avoid pressure on globe
167
Brachial plexus, radial, and ulnar palsies can occur in ___ position(s)
Any
168
Common peroneal palsy can occur in ___ positions
Lithotomy/decubitus positions
169
How can you avoid nerve palsy injuries?
Use padding over bony prominences and avoid stretching/compression of these areas
170
What are 3 high-risk cases for intraoperative awareness?
- Major trauma*
- Obstetrics
- Cardiac surgery
Up to 10x risk
171
3 risk factors for Intraoperative awareness
- Female
- Younger
- Obese
172
What is the most common transient eye injury?
Corneal abrasion
173
What is the most common cause of post-operative loss of vision?
Ischemic optic neuropathy (ION)
Caused by optic nerve infarction d/t decreased oxygen delivery to the optic nerve
174
ION is commonly reported after what 4 surgeries?
- Cardiopulmonary bypass
- Radical neck dissection
- Abdominal and hip procedures
- Spinal surgeries in prone position*
175
What positions contribute to ION?
- Prone
- Head down
- Compressed abdomen
All compromise venous return to the heart*
176
ION onset
Immediately post-op through 12th post-op day
177
What are 4 types of allergic rxns?
Type I-IV
178
Type I allergic reaction
Immediate—anaphylaxis*
179
Type II allergic reaction
Cytotoxic (antibody-mediated, blood type incompatibilities) i.e.: hemolytic transfusion reactions, autoimmune hemolytic anemia, heparin-induced thrombocytopenia
180
Type III allergic reaction
Immune complex (i.e.: RA, SLE)
181
Type IV allergic reaction
Delayed, cell-mediated, cytotoxic (i.e.: contact dermatitis)
182
Anaphylactoid reaction does NOT depend on ___
IgE antibody interaction with antigen (anaphylaxis does)
183
Anaphylactic/anaphylactoid reactions can be clinically ___ and equally ___
Clinically indistinguishable; equally life threatening
184
What is the most common cause of anaphylaxis during anesthesia?
Muscle relaxants
185
What are two hypnotic agents that can cause allergic reactions?
- Propofol
| - Pentothal
186
What is the second most common cause of anaphylaxis during anesthesia?
Latex!
187
What 6 foods cross-react with latex?
- Mango
- Kiwi
- Passion fruit
- Banana
- Avocado
- Chestnut
188
Airway mortality is NOT due to difficulty ___, it is due to failure to ___
Intubating; failure to ventilate
189
What is a late sign of MH?
Core temperature rise as much as 1 degree Celsius every 5 minutes
190
What causes MH?
Uncontrolled release of Ca from the sarcoplasmic reticulum, leading to constant muscle contraction
191
What triggers MH?
-All halogenated agents (so not nitrous oxide) + succs (depolarizing muscle relaxant)
192
What is the treatment for MH?
Dantrolene 2.5 mg/kg q 5 mins; max dose 10 mg/kg
193
How does dantrolene work?
Binds to ryanodine receptor and inhibits calcium release from the SR
194
What should you do if laryngospasm occurs?
- 100% O2
- Deepen anesthesia
- Positive pressure
195
What are two main signs of bronchospasm?
- High peak inspiratory pressures
| - Wheezing
196
What should you do if bronchospasm occurs?
- 100% O2
- Deepen anesthesia
- Albuterol
- Treat the underlying cause
197
What are 3 causative agents of fire in the OR?
Oxygen + heat + fuel = fire
```
Oxygen = anesthesia
Heat = surgeon’s cautery
Fuel = surgical nurse’s alcohol prep
```
198
What should you do if there is a fire in the OR?
- Disconnect the circuit
- Pour sterile water/saline down ETT
- Replace patient’s ETT quickly
199
Keep FiO2 below ___ for tonsillectomy/ENT surgery
30%
200
Total body water = ___% total body weight
60%
201
Intracellular volume = ___%
40%
202
Extracellular volume = ___%
20%
203
ECF is comprised of what two compartments?
- Interstitial fluid (75% ECF)
| - Plasma (25% ECF)
204
Interstitial fluid
75% ECF; fluid in tissue spaces
205
Plasma
25% ECF; intravascular fluid; high concentration of plasma proteins (albumin) that remain in vascular space
206
TBW is ___% male’s weight
55%
207
TBW is ___% female’s weight
45%
208
TBW is ___% infant’s weight
80%
209
ICF has high concentration of ___
Potassium
| Also contains phosphate and magnesium
210
ECF has high concentration of ___
Sodium
| Also contains chloride
211
___ is the main determinant of osmotic pressures
Albumin
212
What are 3 sources of intraoperative fluid loss?
- Insensible loss
- Third space loss
- Blood loss
213
What are insensible losses?
- Urine
- Feces
- Sweat
- Respiratory tract
214
Replace insensible fluid losses with ___ cc/kg/hr
Crystalloid 2 cc/kg/hr
215
Third space loss is fluid lost from ___ space to ___ space
Intravascular space (plasma) to interstitial space
216
Minimal trauma fluid replacement
3-4 cc/kg
217
Moderate trauma fluid replacement
5-6 cc/kg
218
Severe trauma fluid replacement
7-8 cc/kg
219
Third space losses become mobilized ___ day post-op
3rd day—may see increase in intravascular volume; caution in patient’s with limited cardiac reserve/renal dysfunction
220
Blood loss fluid replacement
Replace 3x blood loss with crystalloid
We do 3x because you have to replace intravascular loss + fluid loss from the extravascular (interstitial) space to replenish the intravascular loss during acute hemorrhage
221
How much colloid should be used to replace blood loss?
1:1 blood loss replacement
222
5% albumin is used for ___
Expansion of intravascular volume
223
25% albumin is used for ___
Treatment of hypoalbuminemia
224
Young healthy patients may lose ___% of circulating blood volume without demonstrating clinical signs
20%
225
Acute blood loss causes vasoconstriction of ___ vessels; blood volume loss of ___% can be masked by this compensatory response
Vasoconstriction of splanchnic/venous capacitance vessels; blood volume loss of 10% can be masked by this compensatory response
226
Indication for blood transfusion = increase ___ of the blood
Oxygen carrying capacity
227
Hgb < ___ g/dL = transfuse
< 6 g/dL
228
In acute hemorrhage, ___ preferred over PRBCs
Whole blood
229
PRBCs are used for treatment of ___ not associated with acute hemorrhage or shock; augments ___ of the blood
Acute anemia; augments oxygen-carrying capacity
230
Decreased risk for ___ with PRBC transfusion over whole blood transfusion
Citrate toxicity//allergic reaction
231
Platelet transfusion for platelet count < ___
50,000
232
Risks of platelet transfusion (3)
- Transmission of viral diseases
- Bacterial infection
- Sepsis
233
FFP = ___ portion of blood; contains all plasma proteins except ___
Plasma; contains all plasma proteins except platelets
234
When would you administer FFP (3)?
- When PT/aPTT > 1-1.5 x normal
- Reversal of warfarin therapy
- Correction of known factor deficiencies
235
Risks of FFP transfusion (2)
- Transmission of viral diseases
| - Allergic reaction
236
Cryoprecipitate contains high concentration of ___
Clotting factors—i.e.: fibrinogen*
237
Cryo is given for ___
Clotting factor deficiencies (i.e.: fibrinogen deficiency)
238
Transfuse Hgb < ___ g/dL in patients with CV/pulmonary disease over the age of 65 years
7 g/dL
239
Transfuse Hgb < ___ g/dL in patients undergoing cardiopulmonary bypass
6 g/dL
240
Transfuse if > ___% blood volume loss
> 30% (1500 cc cumulative loss)
241
Transfuse platelets if platelet count < ___
< 50,000
242
Give FFP if INR > ___; PT ___ x normal; aPTT > ___x normal
INR > 2; PT 1.5 x normal; aPTT > 2x normal
243
Give cryo if fibrinogen < ___
< 80-100
244
Local anesthetics are weak ___
Weak bases
245
What is pKA?
The pH at which you have 50% ionized (charged) and 50% nonionized (uncharged)
246
Lower PKA = ___ onset of action
Faster (because you have more in the uncharged form)
247
Uncharged form = most ___
Lipid soluble—this is what accesses the axon
248
Local anesthetics block the influx of ___ into the cells to prevent conduction of action potentials
Sodium
THRESHOLD POTENTIAL IS NOT REACHED
249
Lipid solubility increases ___
Potency
250
High degree of protein binding = ___ duration of action
Longer
251
PKA determines ___
Onset of action
Lower PKA = faster onset because you have more nonionized form
252
___ fibers are more easily blocked than ___ fibers
Thin fibers, thick fibers
253
Which is more easily blocked—myelinated or unmyelinated axons?
Myelinated
254
Where is the block produced specifically—node of ___
Ranvier
255
Which type of locals are metabolized more quickly?
Esters are metabolized more quickly than amides (d/t cholinesterases in the circulation)
256
Half-life of esters
~1 min
257
Byproduct of ester metabolism = ___
PABA (p-aminobenzoic acid)
258
Where are amides broken down?
Liver—patients with severe hepatic disease may be more susceptible to adverse reactions
259
Half-life of amides
2-3 hours
260
What is baricity?
Density of local anesthetics compared to density of CSF
261
How does sodium bicarb affect local anesthetics?
Increases concentration of nonionized (free) base, thus increasing the rate of diffusion of the local/speeding onset of action
262
Ester anesthetics may trigger allergic reactions in persons sensitive to ___ or ___
Sulfonamides or thiazide diuretics
263
IV injection of ___ or ___ may result in CV collapse that is refractory to therapy because of high degree of tissue binding of these agents
Bupivicaine or etidocaine
264
Spinal anesthesia = injecting into the CSF within the ___ space
Subarachnoid/intrathecal space
265
What is the most common causative organism in epidural abscess? Which is a growing concern?
Most common = Staph aureus; MRSA is a growing concern
266
What are 6 absolute contraindications for a spinal?
- Patient refusal/lack of cooperation
- Increased ICP
- Coagulopathy
- Skin infection at the site
- Uncorrected hypovolemia
- Spinal cord disease
267
Aspirin and spinal
No contraindication
268
Plavix and spinal
Discontinue 7 days preoperatively
269
Heparin and spinal
Place catheter 1 hour before scheduled dose; remove catheter 1 hour before next dose
270
What are signs of spinal/epidural hematoma?
- New onset weakness to lower limbs and sensory deficit
- New onset back pain
- New onset bowel or bladder dysfunction
271
Must diagnose and surgically decompress hematoma within ___ hours for best outcome
Within 8 hours
272
Spinal needles are placed below ___, as the mobility of the spinal nerves reduces the danger of needle trauma
L2
273
CSF specific gravity =
1.004-1.009
274
What are 3 types of local anesthetic solutions?
- Hyperbaric
- Hypobaric
- Isobaric
275
Which type of local solution is most commonly used?
Hyperbaric
276
What is hyperbaric mixed with?
Glucose
277
Hyperbaric flows ___
Down to most dependent part d/t gravity
278
Hypobaric solution is mixed with ___
Sterile water
279
Hypobaric solutions flow ___
Up to highest part
280
Hypobaric solutions are used for ___ procedures
Perineal procedures in prone
281
Isobaric solutions
Predictable spread through CSF independent of patient position
282
Increasing dose of isobaric anesthetic will affect ___, rather than spread to a higher dermatome
Duration of action
283
Lateral position—hypobaric/hyperbaric solutions
- Affected side UP if using hypobaric solution
| - Affected side DOWN if using hyperbaric solution
284
Sitting position is often used with ___ anesthetics
Hyperbaric
285
Prone position is often used with ___ anesthetics
Hypobaric
286
Prone position is useful for procedures on ___, ___, and ___
Rectum, perineum, and anus
287
Increased resistance is felt with spinal needle as it passes through ___
Ligamentum flavum
288
As spinal needle is passed beyond the ligamentum flavum, a sudden ___ is felt
“Pop” or loss of resistance
289
Correct placement of spinal needle is indicated by ___
Free flow of CSF into the hub of the needle
290
Paresthesia occurring with placement of spinal needle requires ___
Immediate withdrawal of needle and repositioning
291
For onset of blockade, monitor BP, HR, and respiration’s every ___ until patient is deemed stable
Minute
292
Fixation of local anesthetic takes approximately ___ minutes
20
293
Neural blockade order of action
Autonomic > sensory > motor (difference of 2 segments, with autonomic fibers being highest level of blockade)
294
Epidural anesthesia = injection of local anesthetic into the ___
Epidural space
295
Onset of epidural anesthesia is ___ and ___
Slower and less intense than spinal
296
Provider has greater control of sensory/motor blockade with ___ vs. ___
With epidural vs. spinal
297
Epidural anesthesia is ___ dependent
Diffusion dependent
298
___ volumes used with epidural anesthesia
Larger—spinal dose is usually 2 ccs; epidural dose is usually 20 ccs
299
Epidural anesthesia takes ___ to achieve than spinal anesthesia
Longer
300
Epidural needle should always enter the epidural space ___ because the space is widest
MIDLINE—decreased risk for puncturing epidural veins, spinal arteries, or spinal nerve roots
301
Epidural test dose—if placed in epidural space, will have ___ effect
Little effect
302
Epidural test dose—if placed in the CSF, will rapidly behave like ___
Spinal
303
Epidural test dose—if injected into an epidural vein, a ___ in HR will be seen
20-30% increase in HR
304
DOA lidocaine
30 mins to 2 hours
305
DOA bupivacaine
2-4 hours
306
DOA ropivacaine
2-6 hours
307
Always have patient on standard hemodynamic monitors/supplemental oxygen when setting up peripheral block—T/F?
TRUE
308
What technique is this?—LA injection targets terminal cutaneous nerves; used to minimize incisional pain; don’t use this technique if local tissue is acidotic/infected; used in dental procedures.
Field block technique
309
What technique is this?—look for sensory nerve with needle, patient feels paresthesia, inject local
Paresthesia technique
310
What technique is this?—look for motor nerve with needle, muscle contracts, inject local
Nerve stimulator technique
311
What is the most favored method for peripheral anesthesia today?
Ultrasound
312
Hypoechoic
Dark, muscles
313
Hyperechoic
White, bone
314
Anechoic
No reflection, fluid and blood
315
Which probe is preferred and good for superficial nerves?
Linear probe
316
Which probe is good for deeper structures but provides a poorer image?
Curvilinear probe
317
What does the nerve look like on ultrasound?
Honeycomb structure; seen on short-axis
318
What alignment is this?—longitudinal/long-axis; can visualize needle better but need good hand-eye coordination; can lose image easily with any slight movement
In-plane needle alignment
319
What alignment is this?—transverse/short-axis; preferred for peripheral nerve blocks and central venous cannulation
Out-of-plane needle alignment
320
What does the needle tip look like in out-of-plane needle alignment?
Looks like a bright white dot on ultrasound
321
What nerves comprise the brachial plexus?
C5-T1
322
What are 4 types of brachial plexus blocks?
- Interscalene block
- Supraclavicular block
- Infraclavicular block
- Axillary block
323
Interscalene block is used for ___ surgeries; NOT for surgery ___
Used for shoulder/upper arm surgeries; NOT for surgery at or below elbow
324
Interscalene block targets ___
C5-C7 roots
325
How can you achieve complete anesthesia of shoulder with interscalene block?
Supplement C3-C4
326
Caution using interscalene block in patients with ___ d/t possibility of phrenic nerve paralysis
Severe pulmonary disease (can result in dyspnea, hypercapnia, and hypoxemia
327
___ artery injection is a risk with interscalene block; what is a sign?
Vertebral artery injection; suspect if immediate seizure activity is observed
328
Interscalene block can cause what syndrome?
Horner’s syndrome—myosis, ptosis, anhydrosis (excessive constriction of pupil, lazy eye, and inability to sweat)
329
What lung complication is possible with interscalene block?
Pneumothorax
330
What nerve palsy can occur from interscalene block?
RLN palsy—hoarseness
331
Supraclavicular block is for surgeries at ___, NOT ___ surgeries
For surgeries at or distal to elbow; NOT shoulder surgeries
332
Supraclavicular block targets ___
C5-T1 divisions
333
Supraclavicular block has risk of ___ palsy in ~50% of patients
Ipsilateral (same side) phrenic nerve palsy
334
What syndrome can supraclavicular block cause?
Horner’s syndrome
335
___ artery puncture is a risk with supraclavicular block
Subclavian artery puncture
336
Supraclavicular block can also cause ___ and ___ (just like infraclavicular block)
Pneumo and RLN palsy
337
Infraclavicular block is for surgeries ___, NOT ___ surgeries
Surgeries at or distal to elbow, NOT shoulder surgeries
338
Infraclavicular block targets level of ___
Cords C5-T1
339
Axillary block targets ___ of brachial plexus
Large terminal branches of brachial plexus
340
Axillary block blocks ___
Entire arm distal to the elbow
341
What type of block is IV regional anesthesia?
Bier block
342
Bier block is good for ___ procedures
Short—45-60 mins; i.e.: carpal tunnel release
343
Bier block—tourniquet must be inflated for ___ minutes to avoid systemic toxicity
15-20 mins
344
Bier block—___ deflation of tourniquet
Slow incremental deflation
345
What are 4 contraindications for ALL brachial plexus blocks?
- Local infection
- Severe coagulopathy
- Local anesthetic allergy
- Patient refusal
346
___ and ___ are favored sites for blocks of terminal nerves
Elbow and wrists
347
Increased risk for ___ with regional blocks (like brachial plexus blocks) because the drugs are rapidly absorbed into the systemic circulation
Toxicity
348
Tibial nerve stimulation results in ___ of foot and toes; ___ of foot
Plantarflexion of foot and toes; inversion of foot (pushing foot down and inward)
349
Superficial peroneal nerve stimulation = ___ and ___ of foot
Abduction and eversion of foot (pushing foot outward)
350
Deep peroneal nerve stimulation = ___ of foot
Dorsiflexion of foot (flexing foot up)
351
What are 5 types of lower extremity nerve blocks?
- Femoral nerve block
- Sciatic nerve block
- Popliteal block
- Saphenous block
- Ankle block
352
What are 3 indications for a femoral nerve block?
- Anterior aspect of thigh procedure
- Superficial surgery on medial aspect of leg or below knee
- Knee arthroscopy*
353
What are 2 unique contraindications for a femoral nerve block?
- Previous ilioinguinal surgery (i.e.: femoral vascular graft, kidney transplant)
- Large inguinal lymph nodes or tumor
354
What are 4 contraindications for ALL lower extremity nerve blocks?
- Patient refusal
- Local infection
- Coagulopathy
- Neuropathy
355
Is neuropathy an absolute contraindication for a lower extremity nerve block?
No, but it definitely needs to be considered
356
What type of surgery would a sciatic nerve block be indicated?
Lower limb surgery
357
Sciatic nerve block is often combined with ___
Other blocks, i.e.: femoral
358
If doing a sciatic nerve block for the lower leg, it is preferable to go ___
Lower
359
What type of surgery would a popliteal block be used?
Lower leg surgery—especially foot and ankle
360
A popliteal block may require ___ coverage
Saphenous
361
Tendons of biceps femoris/semi-tendinosus muscle are ~ ___ cm from the popliteal fossa crease
~7cm
362
When would a saphenous block be used?
- Saphenous vein stripping/harvesting (for CABG)
| - Analgesia for knee surgery in combo with other techniques
363
A saphenous block is typically used in combination with ___ nerve block to supplement medial foot/ankle surgery
Sciatic nerve block
*Popliteal block (used for surgery on foot/ankle) may also require saphenous coverage
364
When would an ankle block be used?
Foot surgery
