Orthopedic Anesthesia Flashcards
(179 cards)
1
Q
What are the two biggest factors associated with development of osteoporosis?
A
- Elderly age
- Menopause
2
Q
What hormonal changes are characteristic of osteoporosis?
A
- ↑ PTH
- ↓ Vit D
- ↓ HGH
- ↓ Insulin-like growth factors
3
Q
What are the four most common meds used to treat osteoporosis?
A
dronate drugs
- Fosamax (Alendronate)
- Actonel (Risedronate)
- Boniva (Ibandronic Acid)
- Reclast (Zoledronate)
meds that ↑ bone density, prevent post-menopausal osteoporosis
4
Q
What 5 fractures are common in pts w/ osteoporosis?
A
- stress fractures
- compression fx of thoracic/lumbar spine
- proximal femur fx
- proximal humerus fx
- wrist fx
5
Q
Osteoarthritis is the loss of ________ ________.
A
Articular Cartilage - bone on bone
leads to inflammation
6
Q
What are 6 symptoms of Osteoarthritis?
A
- pain
- crepitance
- decreased mobility
- joint deformity
- Herberden Nodes
- Bouchard Nodes
7
Q
Differentiate between Bouchard’s nodes and Heberden’s nodes.
A
- Bouchard’s = proximal interphalangeal joints
- Heberden’s = distal interphalangeal joints
8
Q
What 6 meds are typically used for OA management?
A
- NSAIDs: Meloxicam
- Opioids
- COX-2 inhibitors: Celebrex
- Topical Voltaren
- Intra-articular steroids
- Chondroprotective agents: Glucosamine, Chondroitin
9
Q
What is a risk factor w/ Voltaren being absorbed systemically?
A
Peptic ulcer disease
10
Q
What drug is the most common chondroprotective agent that helps protect the articular joint?
A
Glucosamine
11
Q
What anesthetic considerations should be given to glucosamine?
A
Glucosamine needs to be stopped two weeks prior to surgery due to PLT aggregation inhibition.
12
Q
Arthritis characterized by morning stiffness that improves throughout the day is….
A
Rheumatoid arthritis
13
Q
Arthritis that is characterized by worsening symptoms throughout the course of the day is…
A
Osteoarthritis
14
Q
Rheumatoid Arthritis is a ________ and ________ inflammatory disease.
A
Chronic & Systemic
15
Q
What is RA characterized by?
A
joint synovial tissue/connective tissue inflammation
* bone erosion
* cartilage destruction
* impaired joint integrity
16
Q
What are 5 symptoms of RA?
A
- pain & stiffness
- anorexia
- fatigue
- weakness
- subcutaneous nodules around joints, extensor surfaces, and bony prominences
17
Q
What labs are typically elevated in a patient with rheumatoid arthritis?
A
- ↑ Rheumatoid factor (RF)
- ↑ Anti-immunoglobulin antibody
- ↑ C-reactive protein (CRP)
- ↑ Erythrocyte Sedimentation Rate (ESR)
18
Q
What common dose of stress dose glucocorticoid is used for RA patients?
A
50mg hydrocortisone (Solu-cortef)
19
Q
What two TNFα inhibitors are commonly used to treat RA?
A
- Infliximab
- Etanercept
20
Q
Which of the following drugs treat RA?
- Methotrexate
- Hydroxychloroquine
- Sulfasalazine
- Leflunomide
A
Trick question. All of them do
- Methotrexate: antimetabolite
- Hydroxychloroquine: antimalarial/antirheumatic
- Sulfasalazine: anti-inflammatory
- Leflunomide: disease modifying antirheumatic drugs (DMARDs)
21
Q
What airway concerns should be considered with RA patients?
A
- Limited TMJ movement
- Narrowed glottic opening
- Cricoarytenoid arthritis
22
Q
Where is the most instability typically located in the cervical spine of RA patients?
A
Atlantoaxial Junction
(be careful not to displace the odontoid process and impinge on the c-spine or vertebral arteries)
23
Q
What are the signs and symptoms of atlantoaxial subluxation?
A
- Headache
- Neck pain
- Extremity paresthesias (especially with movement)
- Bowel/bladder dysfunction
24
Q
What airway management techniques can be used when there is concern for atlantoaxial subluxation?
A
- video laryngoscopy
- manual in-line stabilization
- awake fiberoptic
25
What are the signs/symptoms of vertebral artery occlusion?
- N/V
- Dysphagia
- Blurred Vision
- Transient LOC changes
26
What ocular syndrome is typical of RA patients?
Sjogren's syndrome
(Dry eyes and mouth)
27
What pulmonary issues are associated with RA?
- Interstitial fibrosis
- Restricted ventilation
## Footnote
affects a:A gradient, closing volumes, Vt, & TLC
28
What type of ventilatory settings would be utilized for an RA patient exhibiting a restrictive ventilatory pattern?
Pressure Control @ 5mL/kg
29
What vascular issues are associated w/ RA?
Vasculitis/Vascular Disease
30
What Cardiac Issues are associated w/ RA?
* pericarditis
* cardiac tamponade
31
T/F: RA can cause gastric ulcers, but does not lead to renal issues.
False.
RA causes gastric ulcers (NSAID use) & renal insufficiency.
32
Orthopedic Injuries are associated w/ what 3 big complications?
1. significant hemorrhage
2. shock
3. fat emboli
33
What artery is typically injured due to pelvic fractures? Where is the bleeding located in this instance?
Iliac artery → retroperitoneal space bleeding
34
What is the typical worst complication of long bone fractures?
Bone marrow fat embolism
## Footnote
Leading to thromboembolic hypoxic respiratory failure
35
What technique is used for intubation of a patient who has c-spine concerns?
MILS
Manual In-Line Stabilization
36
Describe the MILS technique
37
How long and at what rate should O2 be delivered before RSI?
100%, 10-15 L/min @ least 3 min
38
What is the mechanism of action of warfarin?
Warfarin inhibits Vitamin K epoxide reductase and limits the availability of Vitamin K throughout the body
39
What is the mechanism of action of LMWH?
LMWH binds to antithrombin thus → no thrombin → no fibrinogen forming into fibrin
40
What are some typical triggers for delirium?
- Hypoxemia
- Hypotension
- Hypercarbia
- Sleep Deprivation
- Hypervolemia
- Infection
- Electrolyte abnormalities
- Pain
- Benzos
- Anticholinergics
- Circadian Rhythm disruption
41
What are 3 CNS concerns that should be assessed post-op?
1. attention & awareness deficits
2. irritability & anxiety
3. paranoia & hallucinations
42
FEV₁ decreases by ___% for each decade of life.
10%
43
What occurs with closing volume as we age?
Closing volume **increases**.
44
What is the goal of regional anesthesia vs general anesthesia?
Avoid:
- DVT
- PE
- EBL
- Respiratory complications
- Death
## Footnote
& improved pain managment!
45
Fat Emboli are common w/ which types of fractures?
* pelvic, femoral
* long bone trauma
46
What causes a fat embolus?
* release/displacement of fat droplets into the venous system
* fx releases mediators that affect the solubility of lipids in circulation
* embolus goes systemic
47
With placement of what device is fat embolism syndrome most likely to occur?
Femoral Medullary Canal Rod
48
What is the s/s Triad of fat embolism syndrome?
When do s/s typically present?
1. Dyspnea
2. Confusion
3. Petechiae
Typically presents in 12 - 72 hrs
49
What lab findings are noted with fat embolism syndrome?
- Fat macroglobulinemia
- Anemia
- Thrombocytopenia
- ↑ ESR
50
What is ESR? What are normal values for males and females?
- Erythrocyte Sedimentation Rate
- Male: 0 - 22 mm/hr
- Female: 0 - 29 mm/hr
51
What does the fat emboli obstruct?
* end organ capillaries - fat is metabolized to free fatty acids
52
What are the systemic inflammatory responses to fat emboli?
* inflammatory cell invasion
* cytokine release = ↑ HR, ↓ BP, dyspnea, confusion
* pulm endothelial injury
* pulm edema
* ARDS
53
What minor s/s can be construed to characterize fat embolization syndrome?
- Fever
- ↑HR
- Jaundice
- Renal Changes
54
What are the respiratory sxms of Fat Emboli Syndrome?
* mild hypoxemia
* bilateral alveolar infiltrates
* dyspnea, edema
55
What are the neuro sxms of Fat Emboli Syndrome?
* drowsiness, confusion, obtundation, coma
56
What type of rash can be seen w/ Fat Emboli Syndrome?
* Petechial Rash: conjunctiva, oral mucosa, skin folds of chest/neck/axilla
57
What are the anesthetic management techniques for fat embolization syndrome?
Supportive Therapy
- 100% FiO₂
- **No N₂O**
- IV Heparin
- CV & Resp support
58
What factors contribute to the development of DVT's?
- **Lack of Prophylaxis**
- Obesity
- > 60yrs old
- > 30min procedure
- Tourniquet use
- > 4 days immobilization
- > Lower extremity fracture
59
Which three surgery types present the greatest risk for DVT formation?
- Hip surgery
- TKA
- Lower extremity trauma
60
When does LMWH need to be initiated?
12 hours preop
or
12 hours postop
61
Can neuraxial anesthesia be done after LMWH has been given?
Yes, if **10 - 12 hours** after the dose.
*Delay next dose 4 hours*.
62
Can an epidural be placed in a patient on LMWH anticoagulation therapy?
No. No indwelling catheters
63
Neuraxial catheters must be removed ___ hours before the intiation of LMWH therapy.
2 hours
64
Can a patient have neuraxial anesthesia if on warfarin?
Only if the **INR is ≤ 1.5**
65
Flip card for Anticoagulation guidelines for Neuraxial procedures.
66
Flip card for additional Anticoagulation guidelines for Neuraxial procedures.
67
What advantages does neuraxial anesthesia present in the prevention of DVT's?
- ↑ extremity venous blood flow (sympathectomy).
- LA systemic anti-inflammatory properties.
- ↓ PLT reactivity
68
What is the maximum dose of TXA? (Tranexamic Acid)
2.5 g
69
What is typical dosing of TXA?
10 - 30 mg/kg
**1000mg is typical**
70
What is the MOA of TXA?
* anti-fibrinolytic that competitively inhibits breakdown of fibrin clots.
* blocks binding of plasminogen and plasmin to fibrin
* prevents breakdown of clots
71
When should we be cautious using TXA?
Pts @ risk of VTE, MI, CVA, TIA
* can cause CV post-op complications
72
What are the main contraindications to using TXA?
* DVT/PE in 12mos
* DVT/PE anticoagulation treatment
* cardiac stent in 1 yr
* DIC
* Seizures
* active clotting
* SAH
73
Tourniquet pain typically begins ___ minutes after application.
45 min
## Footnote
* increased HR & BP, diaphoresis
74
The width of a tourniquet must be greater than ____ its diameter.
½
75
How long can tourniquets be placed on an extremity?
- 2 hours is typically not exceeded
- **3 hours is max**.
76
What mmHg is typically used for thigh tourniquets?
300 mmHg
(or 100 mmHg > SBP)
77
What mmHg is typically used for arm tourniquets?
250 mmHg
(or 50 mmHg > SBP)
78
What things need to be documented when a tourniquet is used?
1. inflation & deflation time
2. total inflated time
3. inflation pressure & adjustments
79
What can prolonged tourniquet inflation time (>2hrs) cause?
* Nerve injury
* ischemia, mechanical trauma
* rhabdo
## Footnote
**deflate every 20-30min to allow for reperfusion**
80
When utilizing a double tourniquet, it is important to remember to...
inflate proximal → deflate distal
81
What 4 factors influence tourniquet pain?
1. tourniquet time/position/pressure
2. anesthesia technique **multi-modal**
3. dermatomal spread/peripheral n. coverage
4. LA dose (density)
82
What occurs with tourniquet deflation?
- Transient lactic acidosis
- Transient Hypercarbia (↑ Vm to eliminate CO2)
- ↑ HR
- ↓ pain
- ↓ CVP, BP, & temp
83
What are some important points of assessment necessary for upper body procedures preoperatively?
- Baseline vitals
- Airway
- Pre-existing nerve conduction issues
- Examine pupils
84
What are 4 diagnoses that require shoulder arthroscopy/arthroplasty?
1. rotator cuff tear
2. subacromial impingement (crepitus and pain w/ movement)
3. glenohumeral instability (shoulder instability)
4. labral tear: ring of cartilage that lines the edge of the shoulder socket
85
What are the cardiac consequences of sitting/Beach Chair position?
- ↓ CO & BP
- ↑ HR & SVR
Due to pooling of blood in lower body (↓ VR)
86
What are the respiratory consequences of sitting/Beach Chair position?
- ↑ FRC & lung volumes
87
West Perfusion Zone 1:
* PA > Pa > Pv
* apex of lung - no blood flow during lung dz or PPV
88
West Perfusion Zone 2:
* Pa > PA > Pv
* Middle portion of the lung - gets blood flow during ↑ pressures (ejection)
89
West Perfusion Zone 3:
* Pa > Pv > PA
* bottom portion of lung - gets perfusion throughout entire cardiac cycle (↓ PVR)
90
West Perfusion Zone 4:
* Compression of the vessels in the very bottom of the lung d/t gravity
* no perfusion
91
What portions of the lung receive better perfusion and what portions receive better ventilation?
1. perfusion: bottom/dependent parts of the lung (lower resistance)
2. ventilation: bottom/dependent parts of the lung (alveoli more compliant)
92
What are the neurologic consequences of sitting/Beach Chair position?
↓ CBF
* Cerebral hypoperfusion - A-line placed @ tragus (level w/ circle of Willis)
Air embolism
pneumocephalus
↓ CPP
93
What is a possible nerve damaged in sitting/beach chair?
Sciatic nerve - if Hips flexed >90 degrees
94
How is venous air embolism prevented in a beach chair patient?
↑ CVP (above 0) to prevent a "suction" effect
95
What is the patho of a VAE?
* entrain air into open vessels
* goes to RV & interferes w/ blood flow into pulmonary artery **pulmonary air lock**
* pulm edema & reflex bronchoconstriction occur
* air can reach cerebral & coronary circulation via patent foramen ovale
* death from CV collapse & arterial hypoxemia
96
In what percent of the population is a patent foramen ovale present?
20 - 30 %
97
How does one treat venous air embolism?
*Besides prevention...*
- Inform surgeon → irrigation & occlusive dressing
- DC N₂O if being used
- Bilateral compression of jugular veins (prevent neuro consequences)
- Place patient in head down position to trap in right atrium
- Withdraw air through right atrial catheter
- CV & Resp support
98
The ultrasound transducer is being utilized to located venous air embolism in a patient. Where do you place the probe?
2ⁿᵈ - 3rd ICS right of sternum
*Over the Right Atrium*
99
Though ultrasound over the right atrium is the most sensitive indicator of VAE (venous air embolism), the most definitive is....
TEE
100
The characteristic sound of a VAE is a _____________ murmur.
"Mill-Wheel" murmur
101
What would be an indicator of a sudden decreased perfusion to the lungs?
↓ EtCO₂
## Footnote
indicating an air lock from VAE & no gas exchange happening
102
________ of the neck in a sitting position patient can accidentally extubate them.
Hyperextension
103
What can hyperflexion of the neck cause to happen with the ETT?
* Endobronchial intubation - mainstem
* Hits carina and causes pt bucking on vent
104
In a sitting position patient, where would one zero their art line?
Tragus of the ear
*Establishes knowledge of brain BP & thus perfusion*.
## Footnote
@ the level of the circle of willis
105
What happens with the bed used for shoulder surgery?
The leg component is moved to the head component
106
What ocular conditions do we want to avoid due to the hypotension inherent to the sitting position?
- Retinal Ischemia
- Ischemia Optic Neuropathy
*Also avoid corneal abrasion*.
107
What 3 problems can occur w/ induced HoTN in shoulder surgeries?
1. stroke
2. retinal ischemia
3. ischemic optic neuropathy
108
What arteries supply the Circle of Willis?
* internal carotid arteries - become the middle cerebral arteries
* vertebral arteries - become the basilar artery (posterior COW)
109
# Circle of Willis
What does the basilar artery supply?
* anterior side of PONS
* supplies: brainstem, cerebellum, occipital lobes, thalamus, hypothalamus
110
# Circle of Willis
What does the Middle Cerebral Artery supply?
* frontal lobe, parietal lobe, temporal lobe
111
What does the Anterior Cerebral Artery supply?
2 parts:
* A1: part of COW, A2: extends from COW
* Supplies: frontal lobe, parietal lobe, corpus callosum, cingulate gyrus (emotion), motor & sensory cortex **(contralateral lower extremity)**
112
# Circle of Willis
What does the posterior cerebral artery supply?
* off back & posterior portion of brain
2 parts:
* P1: part of COW, P2: extends from COW
* Supplies: occipital lobe (vision), temporal lobe (memory), thalamus, midbrain (visual reflexes & motor coordination), corpus callosum
113
There is a 40cm distance from the patients heart to their brain. The patient's BP measured on the arm is 120/70. What is the estimated BP in the brain?
40cm x 0.77mmHg = 30.8mmHg
120 - 30.8 = 89.2mmHg
70 - 30.8 = 39.2mmHg
The patient's brain BP is **89/39** Thus indicating hypotension and necessary correction.
114
A standing patient's NIBP on the arm is 134/92. The distance between the patient's knee and the NIBP cuff is 120cm. What is the BP in the patient's knee?
120 x 0.77 = 92.4
134 + 92
92 + 92
Patient's "knee" BP standing up is 226/184
115
Is general or regional preferred for shoulder arthroplasty/arthroscopy?
* GETA w/ muscle relaxation = need secure airway
## Footnote
Regional could be primary or additive w/ GETA - less GA w/ block
116
What is the Bezold-Jarisch reflex?
Cardiac inhibitory reflex resulting in signification HoTN & ↓HR.
Stimulus: ↓ VR, hypovolemia
Afferent signal: vagus n. to medullary vasomotor center
Effect: increased PSNS & decreased SNS activity
## Footnote
**can avoid this reflex w/ increasing preload & 5-HT3 antagonist**
117
What are the 2 approaches for a brachial plexus block?
1. Interscalene: b/w middle & anterior scalene muscles
2. Supraclavicular approach anatomy: 1st rib, SC artery, brachial plexus
118
What are possible complications of a brachial plexus block?
- Respiratory depression
- Horner Syndrome
- Hoarseness
- Dysphagia
119
Why can respiratory depression occur with brachial plexus blocks?
Hemidiaphragmatic Paresis from Phrenic nerve blockade.
## Footnote
Especially w/ the interscalene approach
120
What is the triad of Horner Syndrome?
- Ptosis
- Miosis
- Anhydrosis
## Footnote
These are really SE of the brachial plexus block
121
What can hoarseness & dysphagia from a brachial plexus block lead to?
* less control of secretions
* passive/active regurg/vomiting
* unable to protect airway = apsiration pneumonitis risk
122
What things should we assess post-op in shoulder surgery?
* nerve injury
* pain management
* delirium/confusion in elderly
123
What position are elbow surgeries usually performed?
* supine or lateral
124
Is CO affected in the lateral decubitus position?
NO - unless venous return is obstructed by using kidney rest
## Footnote
ABP may fall d/t ↓ vascular resistance (R side > L side)
125
What are the respiratory consequences of a lateral decubitus position?
(VQ mismatch)
- ↓ ventilation of **dependent** lung.
- ↑ perfusion of **dependent lung**.
## Footnote
* this is true for mechanically ventillated pts, spont. breathing will have better ventilation to dependent lung.
126
During mechanical ventilation in left lateral decubitus patient, which lung is overventilated?
Right lung (nondependent lung) (↑ compliance)
127
During mechanical ventilation in left lateral decubitus patient, which lung more perfused?
Left lung (dependent lung) - gravity
128
Where is an axillary roll placed on a lateral decubitus patient?
Caudad to the axilla to avoid compression of the neurovascular bundle.
129
What other positioning concerns are there w/ lateral decubitus?
* upper arm on pillows or in allen arm rest
* pillow b/w knees, lower leg slightly flexed to prevent nerve stretching
* check for eye pressure & dependent ear pressure
* breasts/genitalia free of pressure
130
Where should a pulse oximeter be placed in a lateral decubitus patient?
Dependent hand to ensure that there is no neurovascular compromise
131
Elbow surgeries need what additional block (in comparison to shoulder surgeries) ?
Musculocutaneous nerve
## Footnote
Can hit this nerve when doing an axillary block
132
# Elbow Surgery
Axillary block nerves covered:
1. median
2. ulnar
3. radial
4. musculocutaneous (in the coracobrachialis muscle)
133
If a bean bag is being used for lateral decubitus positioning, what should we ensure?
* there is enough room for excursion of the abdomen when pt is breathing
* The bean bag can cause ↓ Vt & FRC; ↑ CV b/c of no excursion room!
134
What are common diagnoses requiring forearm/hand surgeries?
1. nerve conduction issues
2. fractures, nerve impingement
3. traumatic amputation
135
Anesthesia management in forearm/hand surgeries:
1. supine on hand table
2. airway - tube tree on opposite side of surgeon
136
What are the steps to a **bier block**?
1. IV start
2. Exsanguinate the arm w/ plastic wrapped around the arm
3. double cuff
4. inflate both cuffs when we inject **lidocaine**
5. deflate distal 1st so it diffuses a little - then deflate proximal cuff
6. keep tourniquet 100mmHg > SBP
137
What do we do if the cuff leaks w/ a bier block?
* DO NOT DEFLATE THE CUFF
* if the pt seizes: BZD & Lipid emulsion
138
What is the lipid emulsion dose for LAST?
1.5mL/kg bolus over 1 min (can repeat q 3-5 min)
Gtt: 0.25-0.5mL/kg/min until stable
Max total: 8mL/kg
139
What 4 things can **increase** 1 yr mortality in Hip Fractures?
1. cardiac & pulmonary conditions
2. DVT
3. Delirium
4. large amounts of extravasated blood
140
What things do we need to assess/consider pre-operatively in Hip Fracture Surgeries?
1. pain management
2. IVF status
3. h&H
4. central line/art line?
5. v/s
6. full stomach - trauma pt
141
Is a patient with a hip fracture induced on the OR table or on the bed/stretcher?
Bed/Stretcher to avoid pain from movement to OR table.
142
What are the benefits of neuraxial anesthesia for hip fracture repairs?
- ↓ delirium
- ↓ DVT
- ↓ hospital stay
- Better pain control
143
What are 8 etiologies for a total hip arthroplasty?
1. OA
2. RA
3. degenerative synovium or cartilage disease
4. Avascular necrosis (femoral head dies)
5. tumors
6. congenital deformity
7. dislocation
8. failed reconstruction
144
What position are total hip arthroplastys?
Lateral decubitus
* operative side up
* ax roll padding
145
Regional or General for Total Hip Arthroplasty?
General - muscle relaxation required
146
What are the 4 parts of a total hip arthroplasty?
1. Acetabular component
2. Plastic Liner
3. Femoral Head
4. Femoral Stem
147
What are the three life-threatening complications of total hip arthroplasty?
- BCIS
- Hemorrhage
- VTE
148
What chemical is bone cement?
PolyMethylMethAcrylate
149
What does bone cement do when introduced to the intramedullary bone surface?
1. Release heat and pressurize (500mmHg!) **intramedullary HTN**
2. Possible embolization of fat, bone marrow, and cement
3. systemic absorption - vasodilation (HoTN)
4. plt aggregation - thrombus formation (tissue thromboplastin release)
5. microthrombus in lungs
6. CV instability
150
What are the 4 intramedullary contents?
1. yellow marrow (fat)
2. red marrow (hematopoiesis)
3. Blood vessels & nerves
4. endosteum: inner membrane - osteoprogenitor cells (bone growth & remodeling)
151
What is the anesthetic management of BCIS?
- Combat ↓BP and ↓Volume
- ↑ FiO₂ & SpO₂
152
What things can be done to prevent BCIS?
1. minimize HoTN & hypovolemia
2. maximize FiO2 & SpO2
3. vent hole in femur (surgeon)
4. lavage femoral shaft
5. avoid bone cement
153
What are the s/s of BCIS?
- **Hypoxia**
- **Hypotension**
- Arrythmias
- pHTN
- ↓CO
154
What are 5 common complications in post-op THA?
1. cardiac events
2. PE
3. pneumonia
4. resp. failure
5. infection
155
In a supine position, spontaneous ventilation favors _______ lung segments, whilst controlled ventilation favors ________ lung segments.
Dependent ; independent
156
What are 4 indications for a hip arthroscopy?
1. femoro-acetabular impingement
2. acetabular labral tears
3. loose bodies - bone fragments
4. OA
157
The most common postoperative peripheral neuropathy is:
a. Ulnar neuropathy
b. Brachial plexus injury
c. Median nerve injury
d. Sciatic nerve compression
a. Ulnar Neuropathy
158
Where are the two major sites of injury in ulnar nerve injury?
Elbow at the **condylar groove** (medial epicondyle of the humerus) and **cubital tunnel**.
159
How is ulnar nerve nerve injury avoided?
Supinate hands (palms up!)
160
What common drugs are often used for "conscious sedation" of a hip dislocation?
Ketamine/Propofol Mix
Succinylcholine
## Footnote
requires closed reduction - no incision
161
What are 3 different anesthetic techniques that can be used for a knee arthroscopy?
1. General
2. Neuraxial/Regional
3. Sedation w/ extra-articular or intra-articular injections
162
What are 2 types of PNB that can be used for knee surgery?
1. Femoral
2. Sciatic
163
What are the possible complications of tourniquet placement for knee surgeries?
- Blood loss on deflation (note for 24hrs)
- Peroneal Nerve Palsy
164
What are the steps to a TKA (Total Knee Arthroplasty) ?
1. Tibial Component: plastic spacer & metal plate
2. Femoral Component
3. Patellar Component: articular of patella cut to receive a button that will glide over the femoral component (prosthesis)
4. Plastic Spacer
165
What three conditions (that anesthesia can control) are most often associated with infection of knee replacements?
- Peri-operative glucose control
- Post-op hypoxia
- Post-op hypothermia
166
# Wound Infections
Clean Wound:
Not inflamed or contaminated
* does not involve an internal organ
167
# Wound Infections
Clean-Contaminated Wound
no evidence of infections
* involves an internal organ
168
# Wound Infections
Contaminated
involves an internal organ w/ spillage of contents from the organ
169
# Wound Infections
Dirty Wound:
* known infection at the time of surgery
170
What 4 things can be done to prevent wound infections?
1. decreased traffic in/out of OR
2. prep and drape
3. pre-op abx
4. use of hoods
171
What comorbidities are associated with amputations?
Diabetics, pressure ulcers
172
What medication classes can be used to treat phantom pain from amputation?
- Neuroleptics
- Antidepressants
- Na⁺ channel blockers
173
What are 3 triggers to phantom pain?
1. weather changes
2. emotional stress
3. pressure on remaining area
174
What are physiologic causes of phantom pain?
* MRI/PET Scan
* remapping of circuitry
* damaged nerve endings
* scar tissue impeding blood supply
* physical memory
* pain prior to amputation
175
# Ankle Block
What nerve innervates the plantar surface?
Posterior Tibial nerve
176
# Ankle Block
What nerve innervates the medial malleolus?
Saphenous nerve
177
# Ankle Block
What nerve innervates the interspace between the great & 2ⁿᵈ toes?
Deep Peroneal nerve
178
# Ankle Block
What nerve innervates the space between the dorsum of the foot and the 2ⁿᵈ - 5th toes?
Superficial peroneal nerve
179
# Ankle Block
What nerve innervates the lateral foot and lateral 5th toe?
Sural nerve
