Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

APEX: Flashcards > Musculoskeletal Dz > Flashcards

Musculoskeletal Dz Flashcards

1
Q

Myasthenia Gravis Patho

A
  • autoimmune dz
  • IgG antibodies destroy POST-junctional receptors (nicotinic Ach)
  • thymus gland plays key role; thymectomy relieves s/s
  • Ach quantity sufficient
  • not enough Ach receptors
  • manifests as skeletal muscle wknss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Myasthenia gravis s/s

A
  • key features:
    ~ muscle wknss later in day or w/ exercise
    ~ improves w/ rest
  • diplopia, ptosis (early)
  • bulbar wknss (dysphagia, dysarthria, drooling)
  • dyspnea w/ exertion
  • proximal muscle wknss
  • may require postop ventilation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Myasthenia Gravis is exacerbated by:

A

Apple - aminoglycosides
P - pregnancy
I - infection
E - electrolyte abnormalities
S - stress

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does myasthenia gravis affect pregnant mother & fetus?

A
  • Pregnancy intensifies s/s in 1/3 of pregnant women
  • Anti-Ach IgG antibodies cross placenta in 15-20% of neonates & cause wknss (can last up to 2-4 weeks)
  • neonates require airway mgmt
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Myasthenia Gravis Tx

A
  • 1st line = oral pyridostigmine
  • corticosteroids, cyclosporine, azathioprine, mycophenolate (immunosuppression)
  • thymectomy (reduces Anti-AchR IgG)
  • plasmapheresis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How can you differentiate b/t cholinergic crisis & myasthenic crisis?

A
  • pyridostigmine OD –> cholinergic crisis
  • Tensilon test = 1-2 mg IV edrophonium
    ~ muscle wknss worse = cholinergic crisis –>
    tx w/ anticholinergic
    ~ muscle wknss better = myasthenic crisis –>
    tx w/ anticholinesterase,
    immunosuppression, plasmapheresis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do patients w/ myasthenia gravis respond to sux?

A
  • Fewer nicotinic Ach (Nm) receptors
  • Resistant
  • Require increased dose (1.5- 2.0 mg/kg)
  • pyridostigmine prolongs DOA of sux
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do patients w/ myasthenia gravis respond to ND-NMB?

A
  • Fewer nicotinic Ach (Nm) receptors
  • Sensitive (potency increased)
  • Reduce dose by 1/2 to 2/3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

5 perioperative risks that increase postop mechanical ventilation in pt w/ myasthenia gravis

A
  1. Dz > 6 years
  2. pyridostigmine > 750 mg/day
  3. VC < 2.9 L
  4. COPD
  5. Surgical approach: median sternotomy> transcervical thymectomy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Eaton-Lambert Syndrome (Myasthenic Syndrome) Patho

A
  • IgG-mediated destruction of PRE-synaptic VG
    Ca+ channels
  • Ca+ entry in presynaptic neuron decreased
  • Decreased amount of Ach released into
    synaptic cleft
  • 60% have small-cell lung CA (oat-cell)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

ELS S/S

A
  • Proximal muscles affected
  • wknss worse in AM, gets better throughout
    day
  • Respiratory muscles & diaphgram weak
  • ANS dysfunction:
    ~ orthostatic hypotension
    ~ slowed gastric motility
    ~ urinary retention
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

ELS Tx

A
  • 3, 4- diaminopyridine (DAP)
    ~ increases Ach release from presynaptic
    nerve

AchE not helpful
Tensilon test does NOT aid diagnosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do pt w/ ELS respond to NMBs?

A
  • Sensitive to sux & NDNMBs
  • Reduce dose
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

ELS Mgmt

A
  • Reversal may be inadequate
  • High risk postop resp failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

ELS vs. Myasthenia Gravis

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Guillain-Barre (acute idiopathic polyneuritis)

A
  • Destruction of myelin prevents nerve conduction in peripheral nerves
  • Precipitated by flu-like illness followed by paralysis
  • Causes: epstein-barr, campylobacter, cytomegalovirus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Guillain-Barre S/S

A
  • Flaccid paralysis begins in distal extremtities & ascends bilaterally
  • Impaired ventilation (intercostal muscles)
  • Difficulty swallowing (facial & pharyngeal muscles)
  • Paresthesias, numbness, pain
  • ANS dysfunction
    ~ tachycardia, bradycardia, hyper/hypotension, diaphoresis, anhidrosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Guillain-Barre Tx

A
  • plasmapheresis
  • IV IgG
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Guillain-Barre Mgmt

A
  • avoid sux (hyperkalemia)
  • sensitive to NDNMBs (decrease dose)
  • increased aspiration risk
  • may require postop ventilation
  • autonomic dysfx = HD instability = a-line
  • exaggerated response to indirect-acting sympathomimetics (avoid ephedrine)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Hypokalemic periodic paralysis

A
  • Skeletal muscle wknss follows a glucose-insulin infusion
  • pt becomes weak after K+ decreases
  • Ca+ channelopathy

AVOID:
- glucose solutions
- K+ wasting diuretics
- B2 agonists
- Sux
- hypothermia

Safe:
- NDNMBs
- Acetazolamide

Tx: Acetazolamide (creates non-anion gap acidosis, protects against hypokalemia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Hyperkalemic periodic paralysis

A
  • skeletal muscle wknss follows oral K+ administration
  • pt becomes weak after K+ increases
  • Na+ channelopathy

AVOID:
- Sux
- LR (solutions w/ K+)
- hypothermia

Safe: everything listed in AVOID on hypokalemia card + acetazolamide

Tx: Acetazolamide (facilitates K+ excretion)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

MH patho

A
  • Inherited disease of skeletal muscle characterized by disordered Ca+ homeostasis
  • Genetic mutation of ryanodine receptor (RYR1)
  • Defective RYR1instructs SR to release too much Ca+ into cell
  • Increase O2 consumption
  • Increased CO2 production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Consequences of increased intracellular Ca+

A
  • rigidity from sustained contraction
  • accelerated metabolic rate
  • depletion of ATP
  • increased O2 consumption
  • increased CO2 production
  • increased heat production
  • mixed resp & lactic acidosis
  • sarcolemma breaks down
  • K+ & myoglobin leak out into blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Conditions NOT associated w/ MH

A
  • Becker MD
  • Neuroleptic malignant syndrome
  • myotonia congenita
  • myotonic dystrophy
  • osteogenesis imperfecta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
3 conditions associated w/ MH
1. King-Denborough syndrome 2. Central core dz 3. Multiminicore dz
25
MH triggers
- VA - sux
26
MOST sensitive indicator of MH
EtCO2
27
Early s/s MH
- tachycardia - tachypnea - masseter spasm - warm soda lime - irregular heart rhythm
28
Intermediate s/s MH
- cyanosis - pt warm to touch
29
Late s/s MH
- muscle rigidity - cola- colored urine - coagulopathy - overt hyperthermia
30
Trismus
- tight jaw that CAN still be opened - normal occurrence w/ sux
31
Masseter spasm
- tight jaw that CANNOT be opened - NMB will not relax jaw
32
What is the definitive test for MH?
Halothane Contracture Test - requires live muscle biopsy
33
How do you prepare for a patient at risk for MH?
1. flush anesthesia machine w/ high flow O2 (20-100 min depending on machine) 2. replace all external parts (CO2 absorbent, circuit, breathing bag) 3. remove vaporizers from machine 4. monitor in PACU 1-4 hours Alternative to flushing machine: - charcoal filter (vapor-clean) - place on inspiratory/expiratory limbs - flush w/ 10 L O2 for 90 sec
34
Dantrolene MOA
muscle relaxant 1. reduces Ca+ release from RyR1 in skeletal muscle 2. prevents Ca+ entry into myocyte --> reduces stimulus for Ca+ induced Ca+ release
35
Dantrolene vial & reconsitution
each vial contains 20 mg dantrolene + 3 mg mannitol reconstitute w/ 60 ml preservative free water
36
Dantrolene dose
- 2.5 mg/kg IV repeat q 5-10 min - stop when s/s subside - continue 1 mg/kg q 6 hr in ICU - SE: venous irritation, muscle weakness -
37
MH Treatment
1. D/C triggering agent, convert to TIVA 2. Call for help 3a. Hyperventilate w/ 100% O2 min FGF 10L/min (CO2 elim, O2 delivery, drives K+ into cell) 3b. Apply charcoal filter (change q 1 hr), change breathing circuit & bag 4. Administer Dantrolene or Ryanodex 5. Cool until temp < 38 C 6. Correct lactic acidosis - NaHCO3 1-2 mEq/kg (titrate per ABG) 7. Treat K+ - Cacl 5-10 mg/kg IV - insulin 0.15 u/kg+D50 1ml/kg - hyperventilate 8. Protect against dysrhythmias - Procainamide 15 mg/kg IV - Lido 2 mg/kg IV 9. Maintain UOP > 2 ml/kg/hr - IVF, mannitol, furosemide 10. DIC (late sign) --> check coags
38
Duchenne muscular dystrophy (DMD)
- dystrophin helps anchor actin & myosin to cell membrane - absence destabilizes sarcolemma during muscle contraction & increases membrane permeability - allows CK & myoglobin to enter blood - Ca+ freely enters cell - extrajunctional receptor populate (hyperkalemia)
39
DMD clinical presentation
- males - atrophy, painless muscle degeneration - kyphoscoliosis - resp muscle wknss - degeneration of cardiac muscle (reduced contractility, papillary muscle dysfx, mitral regurg, CHF, cardiomyopathy) -EKG changes: ST, short PR interval, deep Q wave - impaired airway reflexes
40
Pt w/ DMD susceptible to what life-threatening condition?
Sux can cause hyperkalemia & cardiac arrest leading to sudden death Also avoid VA
41
Scoliosis
lateral & rotational curvature of spine & ribcage
42
Cobb angle
Describes magnitude of spinal curvature - 2 most displaced vertebrae identified - line is drawn parallel to each - perpendicular line drawn from each of these lines - angle where they intersect = cobb angle
43
Cobb angle 40-50
indication for surgery
44
Cobb angle 60
decreased pulmonary reserve
45
Cobb angle 70
pulmonary symptoms
46
Cobb angle 100
- impaired gas exchange - increased risk postop pulmonary complications
47
Scoliosis pulmonary changes
48
Scoliosis cardiac changes
- RV hypertophy - EKG: RV strain RA enlargement - MV prolapse - mitral regurg - coarctation of aorta
49
Scoliosis Mgmt
- cervical scoliosis - difficult intubation - N2O increases PVR - correction higher than T8 may require one-lung ventilation - significant blood loss - at risk VAE
50
Somatosensory Evoked Potentials (SSEP_
- monitors posterior spinal cord (dorsal column), which is perfused by posterior spinal arteries - monitors sensory fx - NMBs do not interfere w/ monitoring
51
Motor Evoked Potentials (MEPs)
- monitors anterior spinal cord, which is perfused by anterior spinal artery - monitor motor fx - do NOT use NMBs
52
6 potential risk of wake-up test
1. IV removal 2. extubation 3. awareness 4. pain 5. air embolism 6. damage to spinal instrumentation
53
Rheumatoid arthritis: airway
1. TMJ- limited mouth opening 2. Cricoarytenoid joints - decreased diameter of glottic opening - hoarseness, stridor, dyspnea, airway obstruction - use smaller ETT 3. c-spine - atlanto-occipital subluxation w/ flexion - limited extension - at risk for quariparesis or paralysis
54
RA patho
- autoimmune dz targeting synovial joints - systemic involvement - cytokines play central role - Hallmark: AM stiffness that improves w/ activity - painful, swollen, warm joints -more common in women - affects proximal interphalangeal & metacarpophalangeal joints in hands & feet
55
Complications of RA
56
What labs are increased w/ RA?
- C-reactive protein - Erythrocyte sedimentation rate
57
RA Tx
- antirheumatics (methotrexate, cyclosporine, entanercept) - NSAIDs - glucocorticoids
58
Systemic Lupus Erythematosus (SLE) patho & S/S
- autoimmune dz characterized by proliferation of antinuclear antibodies
59
What can exacerbate SLE?
60
SLE Tx
- corticosteroids - NSAIDs - immunosuppressants - antimalarials
61
SLE Mgmt
- cricoarytenoid arthritis = airway obstruction, swelling; smaller ETT
62
What immunosuppressant drugs increased DOA sux?
cyclophosphamide
63
Marfan Syndrome
Connective tissue d/o w/ autosomal dominant inheritance - associated w/: aortic insufficiency, AAA, aortic dissection, mitral prolapse, spontaneous pneumo (high) - tall w/ pectus excavatum (sunken chest), kyphoscoliosis, hyperflexible joints - pregnancy increases risk of CV complications
64
Ehlers-Danlos Syndrome
Inherited d/o of procollagen & collagen - associated w/ aneurysms, increased bleeding tendency, AAA -* bleeding into joints - avoid regional - risk of pneumo
65
Osteogenesis imperfecta
Connective tissue d/o w/ autosomal dominant inheritance - * brittle bones ~ careful w/ positioning, BP cuff - careful airway mgmt (risk cspine fracture) - kyphoscolisos - pectus excavatum - increased serum thyroxine ( increased BMR & VO2 --> hyperthermia) - *Blue sclera
66
Multiple Sclerosis
Demyelinating dz of CNS - sensory, motor, ANS dysfunction - bulbar muscle dysfx - AVOID sux (hyperkalemia) - S/S exacerbated by stress and increased temp - Tx w/ corticosteroids, interferon, azathioprine
67
Myotonic Dystrophy
Prolonged contracture after a voluntary contraction - dysfx Ca+ sequestration by SR - can interfere w/ ventilation & intubation - at risk for: ~ aspiration ~ resp muscle wknss ~ cardiomyopathy, dysrhythmias ~ sensitive to anesthetic agents
68
3 things that increase risk of contractures in pt w/ myotonic dystrophy
1. Sux 2. NMB reversal w/ AchE 3. Hypopthermia
69
Scleroderma
Excessive fibrosis in skin & organs, particularly microvasculature CREST syndrome
70
CREST syndrome
Calcinosis Raynaud's Esophageal hypomotility Sclerodactyly Telangiectasia (spider veins- increase risk mucosal bleeding; problematic during airway manipulation-esp nasal intubation)
71
Paget's Dz
Excessive osteoblastic & osteoclastic activity causes thick, weak bone deposits - excessive PTH or Ca+ deficiency - pain & fractures most common

APEX: Flashcards (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions