AP 2 Test 4 Flashcards
1
Q
What vessel supplies the anterior 2/3rds of the spinal cord with blood
A
Anterior spinal artery
2
Q
From what vertebral levels does the Artery of Adamkiewicz stem from in the majority of patients (60%)?
A
T9-T12
3
Q
What is a collective term for disorders of the spinal cord?
A
Myelopathy
4
Q
What is a collective term for disorders of the spinal nerve roots?
A
Radiculopathy
5
Q
Between which layers of the spinal cord are the vessels supplying the cord with blood located?
A
Between the arachnoid and pia mater
6
Q
What is spina bifida
A
Failure of fusion of one or more vertebral arches
7
Q
What is special about the anatomy of the vessels in the vertebral plexus?
A
They are valveless
8
Q
Which vertebrae do the vertebral arteries travel through?
A
C1-C6
9
Q
Which directions do most herniations of the spinal cord occur in?
A
Posteriorly and laterally b/c the posterior ligament is not very wide
10
Q
What is important to ask pre-op when assessing pain of a patient presenting for a spinal surgery?
A
Where their pain is and what medication they are taking for it
11
Q
Which table used in spinal surgeries helps decompress the epidural veins and prevent bleeding?
A
Jackson table
12
Q
What is the most common intubation technique for a C1-C2 fusion surgery?
A
Fiberoptic intubation
13
Q
What are the extubation considerations for a C1-C2 fusion surgery?
A
Delayed extubation so swelling can go down
14
Q
What is an important structure that the surgeon must be careful of during an ACDF that could injure the patient’s airway if damaged?
A
Recurrent laryngeal nerve
15
Q
What is a cervical laminoplasty?
A
A small section of the lamina is moved to expand the spinal canal to relieve pressure on the spinal cord or nerves
16
Q
What test is done after a posterior cervical fusion to test dural closure?
A
Valsalva
17
Q
What airway device may be needed during thoracic spine reconstruction and fusions of the T1-T8 spine?
A
Double lumen tube
18
Q
What is scoliosis?
A
Lateral curvature and rotation of vertebrae
19
Q
What measurement indicates the severity of respiratory impairment due to scoliosis?
A
Cobb angle
20
Q
The lungs develop until what age?
A
8
21
Q
How is FEV1/FVC affected in a patient with scoliosis?
A
Not affected - normal ratio
22
Q
What pulmonary pattern presents on a flow-volume loop of a patient with scoliosis?
A
Restrictive
23
Q
A patient with scoliosis has a vital capacity that is __-__% the normal value
A
60-80%
24
Q
How does scoliosis affect lung volumes?
A
Decreased TLC, FRC, inspiratory capacity, expiratory reserve
25
Worsening pulmonary function due to scoliosis has to do with what aspects of the disease?
- How many vertebrae are involved
| - How cephalad the discurvature lies
26
What cardiovascular issues occur in patients with scoliosis?
- Pulmonary HTN
- Right ventricular hypertrophy
- Mitral valve prolapse
- Cardiomyopathy
27
What pre-op workups are standard for almost every scoliosis surgery?
- CBC
- Type and screen
- Chest X ray
28
What pre-op test is needed if a patient with scoliosis has a history of pulmonary HTN?
ABG
29
What is a common anesthetic plan for patients with osteoporosis coming for a kypho- or vertebro- plasty?
Prone MAC
30
What huge nerve creates pain in the lower back and hip and down the back of the thigh when it is impinged?
Sciatic nerve
31
Vertebral roots of the sciatic nerve
L4-S3
32
If there is a spinal cord herniation between L4 and L5, which nerve root is being compressed?
L5
33
Most surgeons want a MAP above __ during lumbar fusion/laminectomies to maintain spinal cord perfusion
80
34
What regions of the spinal cord are the largest?
Cervical and lumbosacral b/c they're innervating the limbs
35
Somatosensory evoked potentials monitor what part of the spinal cord?
Posterior cord
36
Motor evoked potentials monitor what part of the spinal cord?
Anterior cord
37
What nerves are stimulated during SSEP?
- Median
- Ulnar
- Posterior tibial
38
What spine surgeries use evoked potentials?
- Scoliosis
- Laminectomy w fusion
- Fractures
- Cord tumor
39
What MAC level can be run when monitoring SSEPs?
0.5-1 MAC
40
How does propofol affect SSEPs?
- Decreases amplitude
| - Increases latency
41
How does etomidate affect SSEPs?
- Increases amplitude
| - Increases latency
42
How does ketamine affect SSEPs?
Increases amplitude
43
How does nitrous affect SSEPs?
Decreases amplitude
44
Where is stimulation occuring during MEP?
Transcranial stimulation
45
What airway adjunct must you use during MEPs to avoid a swollen tongue?
Bilateral bite blocks
46
Where is the response to SSEPs monitored?
In the brain
47
Where is the response to MEPs monitored?
Hands, feet, teeth
48
During which evoked potential monitoring can you not use NMB?
Motor
49
What is the max MAC level you can use during MEP monitoring?
0.5 MAC
50
What anesthetic technique is commonly used when monitoring MEPs?
TIVA
51
What does spontaneous EMG monitor?
Muscle activity in a specific peripheral nerve when stimulated
52
What nerve is stimulated with a NIMs tube?
Recurrent laryngeal nerve
53
What is the purpose of triggered EMG?
To determine whether a pedicle screw is properly located
54
When should you considering setting up blood for spinal surgeries?
- When the patient has a tumor b/c usually you cannot use cell saver
- Multiple redo
- Multilevel surgery
- If surgeons are working near great vessels
- If the patient is anemic
- ESRD
55
What is spinal shock?
Flaccid paralysis below a spinal cord injury that causes loss of sensation and vascular reflexes
56
How are vitals affected when a patient has spinal shock?
Hypotension and bradycardia due to increased vagal tone
57
If a patient with spinal shock does not have tachycardia in response to hypovolemia, you know the injury occurred at what levels
T1-T4 - cardiac accelerators
58
Patients with spinal shock can only have succinylcholine in the first __ hours of the injury
48
59
When does hyperkalemia due to spinal shock peak?
2 weeks
60
How should CO2 levels be maintained in a patient with spinal shock?
Avoid hypocarbia because that will decrease spinal blood flow
61
Autonomic hyperreflexia can occur with a complete transection above what spinal level?
T6
62
What is autonomic hyperreflexia?
Vasoconstriction below the level of a spinal transection but vasodilation above the transection - occurs after spinal shock has worn off and is set off by a stimulation below the level of the injury
63
What are the cardiovascular signs of autonomic hyperreflexia?
Hypertension with bradycardia
64
Treatment for autonomic hyperreflexia
- Stop surgery
- Deepen anesthetic
- Nitroglycerin
65
Which spine surgeries have the highest incidence of post-op blindness
- Scoliosis
| - Posterior lumbar fusion
66
How does ischemic optic neuropathy occur (ION)?
Decreased blood supply and O2 delivery to the optic nerve
67
What type of ION is more common after spine surgeries?
Posterior
68
Patients in the prone position are at risk of what eye injury?
Central retinal artery occlusion
69
What treatments are available for central retinal artery occlusion?
- Stellate ganglion block
- Ocular massage
- Acetazolaminde
- 5% CO2 in oxygen inhaled
- Local hypothermia
70
What are the surgical risk factors for post-op vision loss?
- Prone positioning
- Wilson frame
- Prolonged robotic surgery with head down
- Surgery greater than 6 hours
- EBL greater than 1 liter
71
What is the anesthetic risk factor for post-op vision loss?
Decreased percent colloid
72
What are the patient risk factors for post-op vision loss?
- Male
| - Obese
73
What are the ASA's recommendation for avoiding post-op vision loss?
- Decrease venous congestion and edema in the head
- Keep head at or above level of the heart
- Include colloid in fluid replacements
74
Venous air embolism is most common in what position?
Sitting
75
What methods can we use to detect venous air emboli?
- TEE
- Precordial doppler
- Mill wheel murmur
76
Cardiovascular signs of a VAE
- Hypotension
- Tachycardia
- Increased PA pressure
- Decreased cardiac output
77
Effect of VAE on saturation
Decreases saturation
78
Effect of VAE on end tidal gases
- Decreased ETCO2
| - Exhaled nitrogen
79
Treatment of VAE
- Flood field with fluid
- 100% O2
- Aspirate if you have CVP
- Fluid bolus
- Pressors
- Jugular compression to prevent further entrainment
- CPR
80
What position is used to treat VAE
Left side down
81
What should be included in your post-op assessment of a patient who's undergone spinal surgery?
- Edema of face/eyes
- Vision
- Position
- Neuro exam
82
What are the risks involved in laser surgery for ENT cases?
- Airway fires
| - Eye injury
83
What are the risks associated with jet ventilation techniques used in ENT surgery?
- Hypercapnia
| - Barotrauma
84
What risks are associated with fiberoptic intubations used for ENT surgery?
A failed intubation means an emergency surgical airway is the backup
85
What risks are associated with nasal intubations?
Epistaxis
86
What risk is associated with TIVAs used for ENT surgery?
Awareness
87
What risk is associated with controlled hypotension in ENT surgeries?
Ischemia
88
What abnormal patient characteristics are commonly found in ENT?
- Head/neck cancers
- Limited c-spine ROM
- Decreased mouth opening
- Decreased tissue compliance
- Receding jaw
- Distorted airway anatomy
- Vocal cord dysfunction
- Large tongue
89
How should analgesia be managed for most ENT surgeries?
Good intraop and postop analgesia is necessary because most procedures are performed on highly reflexogenic areas
90
It's common to keep the patient's systolic pressure under ___ mmHg to maintain a bloodless field for ENT surgeries
100
91
What is the goal MAP for patient's undergoing ENT surgery in order to maintain a bloodless field?
60-70
92
What are the various types of endoscopies used in ENT surgeries?
- Laryngoscopy
- Microlaryngoscopy
- Esophagoscopy
- Bronchoscopy
93
What are common indications for endoscopies?
- Voice disorders
- Stridor
- Hemoptysis
94
What are pre-op considerations for endoscopies?
- Focus on H&P to look for any potential airway problems
| - Review prior notes and imaging from ENT clinic
95
If you aren't expecting to be able to easily mask ventilate or DL your patient in an ENT surgery, what should be done?
Secure the airway before induction with a fiberoptic bronchoscope or awake tracheostomy
96
What are the critical steps when preparing for a fiberoptic intubation?
- Have patient mentally and pharmacologically prepared
- Have ALL equipment prepared
- Make sure the ENT surgeon is in the room so they can assist
97
What is the dose of atropine when used as an antisialagogue for fiberoptic intubation?
0.5-1mg IV or IM
98
What is the dose of glycopyrrolate when used as an antisialagogue for fiberoptic intubation?
0.2-0.4mg IV or IM
99
What is the loading dose of dexmedetomidine when used as a sedative?
1mcg/kg over 10 min
100
What is the infusion dose of dexmedetomidine when used for sedation?
0.2-0.7mcg/kg/hr
101
Dose of Alfentanil
100-1000mcg IV
102
When should antisialogogues be given for a fiberoptic intubation?
20-30min prior to airway manipulation
103
#1 side effect of dexmedetomidine
Bradycardia
104
Which commonly used antisialogouge crosses the blood brain barrier and can cause psychosis, confusion, and dizziness?
Atropine
105
What are the advantages to using Afrin nasally before local topicalization for nasal intubation?
It provides vasoconstriction and keeps the lidocaine from getting absorbed systemically
106
How should lidocaine swabs be used before a fiberoptic intubation?
Swab the patient's nose with 2-4% lidocaine and leave for 5-15 minutes before intubation
107
What cranial nerve innervates the nasal cavity and turbinates?
Trigeminal
108
What are the topicalization options available for the oropharynx and larynx?
- Gargle with lidocaine
- Benzocaine spray (hurricaine)
- Facemask or oral nebulizer with 2-4% lidocaine
- Lidocaine ointment to posterior pharynx with tongue depressor
- Trans-tracheal block
109
What issue can occur when too much hurricane (benzocaine) spray is applied?
Methemoglobinemia
110
What membrane is pierced during a trans-tracheal block?
Cricothyroid membrane
111
What cranial nerve innervates the oropharynx and posterior third of the tongue?
Glossopharyngeal
112
What cranial nerve innervates the epiglottis and more distal airway structures?
Vagus
113
How must muscle relaxation be managed for a laryngeal endoscopy?
There must be masseter muscle relaxation until the end of the case, can be achieved with intermittent non-depolarizing blockade boluses or a SUX infusion
114
What can occur if you run a sux infusion too long?
You can get a Phase II blockade and the sux will act like a non-depolarizing blockade
115
What tube is often used for a laryngeal endoscopy?
Specialized microlaryngoscopy tube
116
What is special about a specialized microlaryngoscopy tube?
- Longer than standard ETT tube
- High volume/low pressure cuff
- Stiffer so it is less prone to compression
117
What is the issue with jet ventilation that you must be very careful with?
It does not ensure ventilation so you must be very careful to allow a full exhalation by watching the chest rise and fall completely
118
How long and at what pressure should inspiration with a jet ventilator be administered?
1-2 seconds at 30-50psi
119
How long should you allow for expiration after a breath with a jet ventilator?
4-6 seconds
120
What anesthetic method is required when using jet ventilation?
TIVA
121
What monitor is not available when using jet ventilation?
ETCO2
122
What cardiovascular considerations should be accounted for during a laryngeal endoscopy?
There are alternating times of extreme stimulation and no stimulation so there is frequent alternations between hypo- and hyper- tension
123
What are the advantages of a metal ETT tube used for laser surgery?
- Combustion resistant
- Kink resistant
- Double cuff
124
What are the disadvantages of a metal ETT tube used for laser surgery?
- Thick walled
- Transfers heat
- Reflects laser beams
125
What are the advantages of a silicone ETT tube used for laser surgery?
- Small
- Non-reflective
- Atraumatic
126
What are the disadvantages of a silicone ETT tube used for laser surgery?
- Silicone is combustible
- Teflon ignition=toxic ash
- Metal foil can unwrap and cause occlusion of airway
127
What is the ideal FiO2 for laser surgery?
21%
128
What should be placed in the airway during laser surgery to limit risk of ETT ignition?
Saline-soaked pledgets
129
What is the fire triad?
1) Oxidizer (O2, N2O)
2) Ignition source (laser, scopes, surgical devices)
3) Fuel (ETT, gauze, alcohol solutions)
130
What should be done when an airway fire occurs?
1) Stop the procedure
2) Stop ventilation and flow of all airway gases
3) Remove the tube and flammable materials
4) Pour saline in patients airway
5) Ventilation with facemask on room air
6) Reintubate as soon as you can
131
What are special pre-op considerations for nasal and sinus surgeries
- Could be a difficult mask ventilation
- Asthma/allergic disorders
- Recent use of ASA/Plavix
132
What airway equipment is often needed for nasal and sinus surgeries?
- Oral airway during mask ventilation
| - Oral RAE
133
What are positioning considerations for nasal and sinus surgeries?
- Arms often tucked
| - Slight head up positioning (make sure patient doesn't have risk factors for CVA)
134
Extubation technique for nasal and sinus surgeries
Usually deep extubation
135
Why is the NIMs tube often used for anterior neck surgeries?
To preserve superior laryngeal, recurrent laryngeal, and vagus nerve branches
136
How does the NIMs tube work?
Stimulates motor nerves and records EMG response
137
How should NIMs ETT be secured?
Midline
138
What muscle relaxants can be used with a NIMs tube?
Sux - NO non-depolarizers!!
139
Pre-op considerations for head/neck cancer surgeries
- Abnormal airway
- Obstruction lesions
- History of radiation
- May need awake fiberoptic/tracheostomy
140
Flap protocol at EUHM states to keep crystalloid fluids under __ liters
5
141
Flap protocol at EUHM states to keep PRBC administration under __ units
3
142
Flap protocol at EUHM states to keep albumin administration under __ liters
2
143
Flap protocol at EUHM states to keep operative time under __ hours
10
144
What are the potential contraindications for immediate post-op extubation according to flap protocol at EUHM?
- Over 75 years old
- Asa 4+
- CV unstable
- Current alcohol abuse
- Greater than 7L fluids intraop
- Major pharyngeal reconstrution
145
Lines/access necessary according to flap protocol at EUHM
- 2 peripheral IVs 18G or larger
| - A line
146
Where should the a-line transducer be zeroed for a flap procedure?
At the level of the brain
147
What nerves need to be preserved during a flap procedure?
Facial and spinal accessory
148
When is it okay to remove anesthesia's ETT during a tracheostomy?
After correct positioning is confirmed by ETCO2 and chest movement and/or auscultation by the surgeon
149
What could be causing increased PIPs after a tracheostomy?
- Malpositioned tube
- Bronchospasm
- Debris/secretions in trachea
- Pneumothorax
150
Intraop considerations for maxillofacial reconstruction and orthognathic surgery
- Long procedure with high EBL
- Throat pack in place
- Head up positioning
- Controlled hypotension
- Local infiltration with epi solutions
- Laser precautions
151
What gas is rarely used for ear surgeries?
N2O
152
What is a post-op risk of ear surgeries?
Increased PONV and vertigo, fall risk
153
How can we decrease risk of PONV from ear surgeries?
- Propofol drip
- Decadron
- Zofran
154
What nerve comes out from under the earlobe and innervates the orbicularis oculi?
Facial
155
What causes a "brain stem anesthetic" that can occur during a retrobulbar block?
There is a subarachnoid space in the orbit, so there can be inadvertent local injection into this space in the eye that will travel to the brain stem
156
How soon after injection do signs of a brain stem anesthetic show up?
4-7 minutes after injection
157
What are the most common symptoms of a brain stem anesthetic?
Patient becomes apneic and unresponsive
158
At the least, what monitor should be used when placing a retrobulbar block?
Pulse ox
159
Functions of the ciliary body
- Secrete aqueous humor
| - Fatten/thin lens to accommodate and focus light
160
What are the long term effects of undiagnosed/treated glaucoma?
It can lead to optic nerve atrophy and causes a shrinking of the visual field until full blindness occurs
161
What supplies the back of the eye with blood?
Choroid plexus
162
What is normal intraocular pressure
Less than 22mmHg
163
How much phenylephrine is contained in 1 drop of 10% phenylephrine?
7mg
164
3 determinants of intraocular pressure
1) Extrinsic pressure
2) Scleral rigidity
3) Alteration of intraocular contents
165
What structure divides the eye into anterior and posterior chambers?
Iris
166
What are the 2 most important determinants of intraocular pressure?
- Rate of formation
| - Drainage
167
4 contributors to increased intraocular pressure
- Acute HTN
- Hypoxia
- Hypercarbia
- Succinylcholine
168
Contributors to decreased intraocular pressure
- Inhaled anesthetics
- CNS depressants
- ND-NMBs
- Hyperventilation
- Hypothermia
- Ganglionic blockers
- Diuretics
169
Afferent nerve in the oculocardiac reflex
Trigeminal (opthalamic branch)
170
Efferent nerve in the oculocardiac reflex
Vagus
171
What events can set off the oculocardiac reflex?
- Pressure on the globe
- Retrobulbar block
- Pressure on orbital contents after enucleation
- Traction on EOM
- Ocular trauma
172
Most common side effect of oculocardiac reflex
Bradycardia
173
Effects from oculocardiac reflex
- Bradycardia
- V tach
- V fib
- Sinus arrest
- Asystole
174
Treatment of oculocardiac reflex
Ask the surgeon to stop - symptoms will quickly end
175
Anesthetic method for cataract surgery
Very minimal sedation
176
What is the issue with using succinylcholine for strabismus procedures?
It causes contractions of the muscle that prevent forced duction testing
177
What is forced duction testing?
Tests to see how well the eye moves and if there is tension in the extraocular muscles
178
Patients with strabismus are susceptible to what intra-op crisis?
MH
179
Strabismus surgery is one of the major risk factors for ____ due to oculo-gastric reflex
PONV
180
What glaucoma medications should we be aware of when managing a patient for glaucoma surgery?
- Timolol - a nonspecific beta blocker that decreases production of aqueous humor, but can get systemic absorption and get bronchospasm and bradycardia
- Pilocarpine
- Meds with epi
181
What block is used for glaucoma and retinal detachment surgeries?
Opthalamic block
182
Intraocular gas used for retinal detachment surgery
Sodium hexaflouride
183
Most common eye injury in ophthalmic surgery
Corneal abrasion
184
What is the result of patient movement during eye surgery?
Blindness
185
What is expulsive subchoroidal hemorrhage?
Sneezing or coughing with the eye open forces the retina outward and squeezes eye contents through the anterior eye wall
186
Additive in local anesthetic for retrobulbar block to penetrate fat surrounding the eyeball
Hyaluronidase
187
Needle used for retrobulbar and peribulbar blockers
Single bevel flat-ground needle
188
Why is a retrobulbar block like a spinal?
Low volume and rapid onset
189
Which facial nerve block only supplies the orbicularis oculi?
Van Lint
190
What block for eye surgery avoids injection into the muscle cone and lowers the risk of globe perforation?
Peribulbar block
191
Advantages of peribulbar block
- Avoids need for facial nerve block
- Avoids muscle cone injection
- Lowers risk of globe perforation
- Direct effect on orbicularis oculi
192
Disadvantages of peribulbar block
- Requires large volume
| - Frequently requires supplementation
193
Indications for peribulbar block
- Long axial length (near-sighted)
| - Previous extra-ocular surgery
194
Patients with spherical correction less than ____ need a peribulbar block
-5.00D
195
Normal axial length
20-22mm
196
Appropriate sedation level for a patient getting an eye block
- Arousable
- Responds to verbal commands
- Not moving
197
Sedation techniques for eye blocks
1) Give small amounts of versed and fentanyl then titrate in propofol until patient is breathing but doesn't respond
2) Give small amounts of fentanyl and versed and give incremental doses of alfentanil (~3-5cc at 1000mcg/cc), monitoring patients respiratory rate and level of consciousness
198
Which type of pain, chronic or acute, is associated with neuroendocrine stress?
Acute pain
199
How long can pain persist and still be labeled "acute pain"
3-6 months
200
What term is defined as "a state of adaption in which exposure to an opioid drug induces changes that result in a decrease of the drug's effect over time"?
Opioid tolerance
201
What is opioid induced hyperalgesia (OIH)?
Prolonged administration of opioids results in a paradoxic increase in atypical pain that appears to be unrelated to the original nociceptive stimulus
202
What is the treatment for OIH?
Decrease opioid administration and work in something that is not working strictly at Mu receptors, such as ketamine
203
What is the most prescribed opioid?
Tramadol
204
What schedule is Tramadol?
Schedule IV
205
What is Actiq?
A fentanyl lollipop that is very short acting
206
What are the receptor actions of Methadone (Dolaphine)
Mu agonist, NMDA antagonist
207
How long does it take for Methadone to reach a steady state for its analgesic action?
5-7 days
208
Why is there a black box warning for Methadone?
Respiratory depression when combined with short acting narcotics
209
How does Methadone affect cardiac conduction/EKG in doses over 60mg?
- Prolongs QT interval
| - Torsades de Pointes
210
What opioid is contained in a Duragesic patch?
Fentanyl
211
What is the black box warning for Duragesic patch?
Don't give unless the patient has been taking...
- 60mg Morphine
- 30mg Oxycodone
- 8mg Hydromorphone for a WEEK or longer
212
When is the Duragesic patch contraindicated?
- Acute pain
| - Post-op pain
213
Opioid side effects
- Resp. depression
- Sedation
- Confusion
- Pruritus
- N/V
- Constipation
- Urinary retention
- Myosis
- Muscle twitching
214
What are the receptor actions of ketamine?
- Mu agonist
| - Non competitive antagonist at the NMDA receptor
215
What metabolite of ketamine can cause prolonged analgesic action?
Norketamine
216
"GINTL" (gin and tonic with lime) encompasses which non-opioid methods of pain management?
```
G - gapapentin/neuronitin
I - ice
N - NSAIDs (ketorolac, celebrex, ibuprofen)
T - tylenol/acetaminophen
L - lidocaine patches
```
217
How do the pupils look when a patient has taken narcotic analgesics such as heroin and various pain pills?
Pinpoint
218
How do the pupils look when a patient has taken meth, cocaine, ritalin, diet pills, or hallucinogens?
Very dilated
219
High doses of methamphetamine may induce what physiologic crisis
Malignant hyperthermia
220
How much does an epidural allow the dosing of narcotics to decrease?
1/10th the dose
221
Benefits of an epidural
Decreases....
- Post-op resp. complications
- Incidence of post-op MI
- Stress response to surgery
- Blood transfusion requirements
222
Surgical regions that indicate epidural placement
- Thoracic
- Abdominal
- Pelvic
- Lower extremity
223
Epidurals are contraindicated when the platelets are below...
100,000
224
Epidurals are contraindicated when what lab value is elevated and indicating infection?
WBC
225
What central nervous system diseases contraindicate epidural placement?
- Multiple sclerosis
| - Syringomyelia
226
In what common surgeries is toradol a contraindication?
- Spinal surgeries
| - Tonsillectomies due to the increase in bleeding
227
Appropriate dose of toradol for most patients older than 60 years old
15mg
228
An epidural can stay into place for up to...
2 weeks
229
Can a patient with a spinal nerve stimulator receive an epidural?
No
230
Can a patient with an intrathecal pump receive an epidural?
Yes
231
A dose of heparin cannot be given within __ hours of an epidural placement
6
232
Low molecular weigh heparins such as Enoxaprin, Dalteparin, Tinazaprin cannot be given within ___ hours of an epidural placement
24
233
How long before an epidural placement must Coumadin be discontinued
3-4 days
234
What lab must be checked before an epidural if the patient has been taking Coumadin
PT
235
How long before an epidural placement must the anti-platelet Ticlopidine be discontinued
14 days
236
How long before an epidural placement must the anti-platelet Plavix be discontinued
7 days
237
How long before an epidural placement must the direct thrombin inhibitor Dibigatran (Pradaxa) be discontinued?
5 days
238
How long before an epidural placement must the Factor Xa inhibitor Xarelto be discontinued?
9 hours
239
How long before an epidural placement must the Factor Xa inhibitor Arixtra be discontinued?
21 hours
240
Complications of epidural placement
- Infection
- Bleeding
- PDPH
- Nerve damage
- Hematoma
- Abcess
- Seizures
- Cardiac arrest
241
Side effects of opioids in epidurals
- Hypotension
- Sedation
- Pruritus
242
If a patient has opioids in their epidural, can you still give them opioids IV or PO?
No
243
Treatment of hypotension from an epidural in the recovery room
- Fluid bolus
- Hold or decrease epidural infusion
- Consider opioid only
244
What are some examples of surgeries that should have opioid only in their epidurals?
- AAA
- HIPECCS
- Lobectomy
245
Primary narcotics given in a spinal
Morphine, hydromorphone
246
Should a patient who comes into preop with a fentanyl patch take it off before they go back for surgery?
No
247
If a patient has intrathecal narcotics, they shouldn't get more than ___ mcg of fentanyl during the case
250
248
Geriatric patients are defined as being __ years or older
65
249
Pharmacokinetic considerations in geriatric patients
- Decreased protein binding so higher unbound drug levels in the plasma
- Slower redistribution
- Increased elimination half life
*ALL LEAD TO INCREASED DRUG LEVELS AT TARGET ORGANS
250
Changes in body compartments in geriatric patients
- Loss of skeletal muscle/lean body mass
- Increased percentage of fat
- 20-30% reduction in blood volume
251
Changes in drug metabolism in geriatric patients
Drug metabolism slows because...
- Clearance decreases b/c liver blood flow, liver mass, and kidney function decreases
- Volume of distribution increases because of increased body fat and decreased albumin levels
252
In general, by what percentage should you reduce the dose of propofol for geriatric patients
20-50%
253
In general, by what percentage should you reduce opioid doses in geriatric patients
50%
254
How does the action of muscle relaxants change in geriatric patients?
The dose needed doesn't change but it may take longer to see effects
255
How does the MAC values of volatile agents change per decade after 40?
MAC decreases by 6%
256
Considerations for benzodiazepine use in geriatric patients
They are more sensitive to CNS effects of drugs so if you are using them reduce the dose
257
Considerations for using anticholinergics and antihistamines in geriatric patients
Can lead to confusion and increased risk of post up delirium
258
What specific drugs should you consider avoiding in elderly patients
- Scopolamine
- Diphenhydramine
- Meperidine
259
How does aging affect arterial function?
- Loss of elasticity causes arterial stiffening
- Increased pressure in aortic root leading to increased SVR
- Can lead to ventricular hypertrophy and impaired diastolic filling
260
How does aging affect venous function?
- Veins stiffen
- Veins are less able to adapt to changes in blood volume
- Volume shifts can cause exaggerated changes in cardiac filling
261
Ventricular changes in geriatric patients
The ventricle stiffens and causes impaired lusitropy (rate of myocardial relaxation) which can lead to dependence on higher filling pressures
262
What is the most common cause of heart failure in patients over 75?
Diastolic dysfunction
263
Elderly patients have less responsiveness to which receptor?
Beta receptors - which decreases their increase in heart rate with stress
264
What cardiovascular qualities do NOT diminish with age?
- Intrinsic quality of the muscle (heart does not weaken due to age alone)
- Peripheral vasoconstriction (patients have enhanced sympathetic tone at rest)
265
How do elderly patient's blood pressures tend to trend in response to anesthetics?
You are likely to see labile blood pressures - very high one minute and very low the next
266
How is vital capacity changed in elderly patients
Decreased vital capacity
267
How is residual volume changed in elderly patients
Increased residual volume
268
How is gas exchange in the airways changed in elderly patients?
- There is a breakdown of elastin connections in the lower airways, making them prone to collapse
- Decreased surface area for gas exchange
- Increased shunting
- Increased dead space
269
How does the time needed for adequate preoxygenation change in elderly patients?
Preoxygenation takes longer in elderly due to the increasing V/Q mismatch
270
Mean PaO2 in patients over 60
81 mmHg (71-91 range)
271
How is the ventilatory response to hypercapnia and hypoxia changed in elderly patients?
They have a blunted response, the change in minute ventilation in response to hypoxia/hypercapnia is about half of what it is in a healthy 25 year old
272
Airway changes in elderly patients
- Decreased C spine mobility
- Smaller mouth opening
- Smaller glottic opening (consider smaller tube)
- Fragile/missing teeth
- Decreased sensitivity of protective airway reflexes (increased risk of aspiration)
273
What factors make elderly patients more prone to hypoxia in the PACU?
- Longer time for preO2
- More difficult airway
- Lower PaO2
- Prone to airway collapse
- Increased work of breathing
- Slower drug clearance
274
Why are elderly patients more prone to hypo- and hyperthermia?
- Don't vasoconstrict or shiver until temps are very low
- Lower resting metabolic rate
- Decreased ability to adjust peripheral and cutaneous blood flow
275
GI changes in elderly
- Decreased HCl
- Decreased saliva
- Decreased taste buds
276
Endocrine hormones that are decreased in elderly
- T3
| - Testosterone
277
Endocrine hormones that are increased in elderly
- Insulin
- Norepinephrine
- Parathyroid hormone
- Vasopressin
278
Lab values that are changed in elderly patients
- Sed rate
- Creatinine
- Alkaline phosphatase
- PSA
- Serum iron
- Total iron binding capacity
279
What is a common finding in elderly patient's urinalysis? Abnormal finding?
- Pyuria common
| - Hematuria not normal
280
CNS structural changes in elderly
- Brain mass decreases
- Decreased cerebral blood flow
- Decreased CMRO2
- Decreased Ach, dopamine, NE
281
What is the most common manifestation of perioperative CNS dysfunction?
Post op delirium
282
What are the signs of post op delirium?
- Acute confusion
- Decreased alertness
- Misperception
- Agitation
283
Post op delirium is __ times as common in elderly patients when compared to younger populations
2
284
What factors pre-dispose geriatric patients to post-op delirium?
- Drug withdrawal
- Benzos
- Tricyclic antidepressants
- Anticholinergics
- Pre-existing depression/dementia
- Metabolic disturbances
285
What metabolic disturbances might cause post op delirium?
Abnormal levels of...
- Na+
- K+
- Glucose
- Albumin
- BUN/Cr
286
Strategies to reduce post op delirium
- Minimize benzos/anticholinergics/antihistamines
- Maintain BP greater than 2/3rds of baseline
- O2 sat greater than 90%
- Gct greater than 30%
287
Common treatable causes of post op delirium
- Hypoxemia
- Hypercarbia
- Hypotension
- Pain
- Sepsis
- Metabolic disturbances
288
Using Haloperidol to treat post op delirium is contraindicated in patients with what disease?
Parkinson's
289
Post op cognitive dysfunction is more common in which types of patients?
1) Elderly
2) Less well educated
3) Previous history of CVA
290
Risk factors for POCD (post-op cognitive dysfunction)
- Advanced age
- Long operation
- Limited education
- Second operation
- Infection
- Respiratory complications
- Cardiopulmonary bypass
- Orthopedic surgery
291
Which pre-existing conditions make elderly patients at a significantly increased risk for POCD?
- MI within 6 months
- Pulmonary edema
- Unstable angina
- Aortic stenosis
292
What is the most important part of a medical history of elderly patients?
Assessing functional status
293
Which type of hypersensitivity reactions are cytotoxic
Type II
294
Which type of hypersensitivity reactions are delayed
Type IV
295
Which type of hypersensitivity reactions are immune complex reactions
Type III
296
Which type of hypersensitivity reactions are immediate
Type I
297
Examples of Type I hypersensitivity reactions
- Atopy
- Urticaria
- Angioedema
- Anaphylaxis
298
Examples of Type II hypersensitivity reactions
- Hemolytic transfusion rx
| - HIT
299
Example of Type III hypersensitivity reaction
Serum sickness
300
Example of Type IV hypersensitivity reaction
Contact dermatitis
301
Signs of contact dermatitis (type IV rxn)
- Pruritus
| - Red weepy skin
302
What is required in order for a type I anaphylactic reaction to occur
Prior exposure to antigen
303
Systems affected by type I anaphylactic reaction
- Cardiovascular
- Pulmonary
- Cutaneous
304
What mediates type I anaphylactic reactions
Antigen:antibody reaction of the immune system
305
Grade IV anaphylactic reaction
Cardiac arrest
306
What exposure causes the fastest and most severe anaphylactic reactions?
IV and mucous membrane
307
Risk factors for anaphylactic reactions
- Mastocytosis (large concentration of mast cells)
- Allergic to drug used
- Risk factors for latex allergy
- Atopy
- History of uninvestigated life threatening event
308
Mechanism of anaphylactic reaction
A susceptible person is exposed to an antigen and their body produces antigen-specific IgE antibodies against it. Re-exposure to this antigen results in mass release of chemical mediators from mast cells and basophils
309
What effect of anaphylaxis do histamine, leukotrienes, and prostaglandins all cause?
Bronchoconstriction
310
What is an anaphylactoid reaction
A reaction that is NOT dependent on IgE antibodies. Mast cells and basophils cause a massive release of histamine
311
Does a patient have to be previously exposed to an antigen in order to have an anaphylactoid reaction to it?
No
312
Patients who are predisposed to anaphylactoid reactions
- Pregnant
- Young
- Patients with atopy
313
What is often the first sign of an anaphylactic reaction under anesthesia?
Hypotension
314
Signs of anaphylaxis under anesthesia
- Hypotension w/ tachycardia
- Circulatory collapse
- Bronchospasm
- Flush
- Edema
- Cardiac arrest
315
Pulmonary signs of anaphylaxis
- Wheezing
- Bronchospasm
- Increased PIP
- Laryngeal edema/stridor
- Acute pulmonary edema
- Acute respiratory failure
- Hypoxia
316
Cutaneous signs of anaphylaxis
- Urticaria
- Flushing
- Periorbital and perioral edema
317
Treatment of anaphylactic reaction
- Stop administration
- 100% O2
- Positive pressure ventilation
- Discontinue volatile anesthetics
- Volume expanders (1-4L)
- Epinephrine
- Put patient's head down
- Cardiac massage
- TEE
318
How does epinephrine treat an anaphylactic reaction?
- Increases cAMP which inhibits mediator release and increases Ca2+
- It's a B2 agonist so it relaxes bronchial smooth muscle
- It's an alpha agonist so it vasoconstricts vessels and increases SVR
319
Why might a patient not respond to catecholamines if they are in anaphylactic shock?
- On beta blockers
| - Increased synthesis of nitric oxide
320
What drugs are helpful if your patient is resistant to epinephrine during an anaphylactic rxn?
- Norepi
- Glucagon
- Phenylephrine
321
Why does vasopressin treat anaphylactic rxns if epinephrine isn't working?
- Causes a non-adrenergic vasoconstriction via V1 receptors
| - Decreases nitric oxide
322
How long after the onset of anaphylactic shock should you wait to give vasopressin?
10-20min
323
What has been shown to treat anaphylaxis when epi and vasopressin aren't working? Why?
Methylene blue because it interferes with nitric oxide
324
Dosage of diphenhydramine to treat anaphylaxis
1-2mg/kg
325
Dosage of hydrocortisone to treat anaphylaxis
2mg/kg
326
Why would Aminophylline be used to treat symptoms of anaphylaxis?
To treat resistant bronchospasm
327
What is indicated by an increase in plasma histamine after a suspected anaphylactic reaction
It indicates mast cell/basophil activation
328
What test can be used to determine immune vs. nonimmunologic anaphylactic reaction?
Tryptase
329
If a patient has both increased tryptase and histamine, what type of reaction did they have?
Immunologic anaphylaxis
330
If a patient has increased histamine but NO increase in tryptase, what type of reaction did they have?
Nonimmunologic anaphylaxis
331
What is the gold standard for detection of IgE-mediated reactions that identifies the culprit agent?
Intradermal skin testing
332
Common offenders of anaphylactic reactions
1) Sux/vec/atracurium
2) Latex
3) Antibiotics
4) Opioids
5) PABA ester local anesthetics
6) Hypnotics (propofol)
333
Is there cross-reactivity between non-depolarizing and depolarizing relaxants?
Yes
334
Is there cross-reactivity between cephalosporins and PCNs?
Yes
335
Is there cross-reactivity between ester and amide local anesthetics?
No
336
Populations at high risk for latex allergy
1) Spina bifida
2) Spinal cord injury
3) Healthcare workers
4) Allergies to bananas, avocados, kiwis
337
Risk factors for protamine allergy
- Seafood allergy
- Diabetics on NPH insulin
- Prior vasectomy
