Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pharmacology Exam 3 > NMBD Intro > Flashcards

NMBD Intro Flashcards

1
Q

dTc and SCh (Anectine)

A
  • 1940 - 1960
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Pancuronium (Pavulon)

A
  • 1960
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Atracurium (tracrium) and Vecuronium (Norcuron)

A
  • 1980
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Rocuronium (Zemuron)

A
  • 1994
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cisatracurium (Nimbex) and Mivacurium (Mivacron)

A
  • 1995 and 1997
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Rapacurium (Raplon)

A
  • 2001
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define the Effect of NMBD

A
  • Interrupt transmission of nerve impulses at neuromuscular junction (NMJ)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Actions of a Depolarizing NMB

A
  • Mimics the action of acetylcholine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Name the only Depolarizing Paralytic on market.

A

Succinycholine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Actions of Non-depolarizoing NMB

A
  • Interferes with the actions of acetylcholine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Name (3) ways NMB minimize incidences of tissue trauma

A
  1. Decreased airway trauma
  2. Facilitates surgical exposure
  3. Minimizes injury from patient movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Name the #1 Purpose of NMB

A
  • Minimize incidence of tissue trauma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name (3) common airway trauma symptoms

A
  1. airway edema
  2. hoarsness
  3. vocal cord injury
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the (5) Clinical Classifications of NMB

A
  1. Depolarizing
  2. Non-depolarizing
  3. Long-Acting
  4. Intermediate Acting
  5. Short Acting
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Name (1) Depolarizing NMB

A
  • Succinylcholine ( Anectine)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Name () Non- Depolarizing NMB

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name (3) Long-Acting NMB

A
  1. Pancuronium (Pavulan)
  2. Doxacurium
  3. Pipecuronium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name (4) Intermediate Acting NMB

A
  1. Atracurium (Tracrium)
  2. Vecuronium (Norcuraon)
  3. Rocuronium (Zemuron)
  4. Cisatracurium (Nimbex)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Name (1) Short Acting NMB

A
  1. Mivacurium (Mivacron)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the potency of neuromuscular blocking drug (NMBD)

A
  • ED95
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Equal Potency of NMB

A
  • Dose necessary to produce 95% suppression of single twitch
  • In the presense of nitrous/barbituate/opioid anesthesia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

ED95: Adductor pollicis muscle

A
  • Single twitch at 1 Hz
  • Ulnar nerve stimulated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Order of the NMB depends on (4) Factors

A
  1. # of presynaptic Ach containing vesicles released
  2. # of postsynaptic Ach receptors
  3. Blood flow to area
  4. Drug potency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

________, ___________ moving muscles block faster than __________ muscles

A
  • Small
  • rapidly
  • large
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Smaller muscles blocks are more _____________, but less ______________.
* rapid * intense
26
27
Name the (2) preferred monitoring sites
* Orbicularis oculi * adductor pollicis
28
Monitoring site: Orbicularis Oculi
* Mores closely reflects diaphragm and laryngeal muscle blockade * Underestimate residual paralysis
29
Monitor Site: Adductor pollicis
* Poor indicator of laryngeal relaxation * Gold Standard for recovery
30
Ulnar Nerve Stimulation
* Place negative electrode (black) on wrist in line with the smallest 1-2 cm below skin crease * postive electrode (red) 2-3 cms proximal to the negative electrode * Response: Adductor pollicis muscle -- thumb adduction
31
TOF: Single Twitch
* Usually 1 Hz/second decreasing to 0.1 Hz q 10 seconds * Continously * Onset of block = fade with each stimulus
32
Double Burst
* 2-3 short twitches following 2-3 short twitches * Use 50 Hz (supramaximal current)
33
Why was the Double Burst developed?
Developed to improve detection of residual block * Fade in 2nd response vs 1st * Qualitatively better than TO4
34
Train of Four (TOF)
* 4 stimuli at 2 Hz in 1/2 second
35
When should TOF be used?
* Prior to NMBD: 4th twitch = 1st twitch .... TOFR 1 * After administration and return of 4 twitches
36
Amplitude of 4th twitch to 1st twitch
* If amplitude of 4th twitch 50% of 1st…. TOFR 0.5 * Experienced anesthetists’ unable to detect fade TOFR > 0.4 * May choose not administer reversal….poor choice * Significant residual TOFR 0.7-0.9
37
Describe Tetanic Stimulation
* Very rapid. 50 Hz for 5 seconds
38
Name (1) cause of Tentanic Stimulation: Sustained Muscle Response
* Depolarizing blocks
39
Name (1) cause of Tetanic Stimulation: Non-Sustained Response
* non-depolarizing block * Phase 2 block w. Succs * Fade related to: (1) presynaptic deplation of Ach or inhibition of release (2) Frequency and length of stimulation
40
Define a Post-Tetanic Stimulation
* single twitch 3 seconds after tetanic stimulation
41
Why does post-tetanic stimulation occur?
* accumulation of calcium during 'tetany" * Excess calcium stimulates Ach release
42
What does it mean if their is no Post- Stimulation response?
* Intense Block
43
Effects of NMBD
44
Bedside evaluation of criteria to extubate
* Head lift * Negative PIP 25 - 30 cmH20
45
Baillard, Clec’h, Catineua et al. Br J Anaesth….. 2 studies
* No anticholinesterace drugs used * No nerve stimulators
46
Baillard, Clec’h, Catineua et al. Br J Anaesth…..: 1st study
* 1st study: 568 patients over 3 months * 1/3 of patients extubated in OR * Postop blockade 42%
47
Baillard, Clec’h, Catineua et al. Br J Anaesth….. : 2nd Study
* 2nd study: Use of nerve stimulators increased from 2%-60% * Neostigmine use increased 6%-42% * Postop blockade decreased to < 4%
48
Anatomy of a NMJ: Synaptic Cleft
* Synaptic cleft 20-50 nm wide with fluid * Contain collagen, acetylcholinesterase
49
Synaptic Cleft: Vesicles
* 5,000-10,000 vesicles release ACh * Ready pool (increased demand) * Calcium dependent
50
Synaptic Cleft: Acetylcholinesterase
1. hydrolysis of Ach 2. to acetic acid and choline
51
Anatomy of a NMJ: Post synaptic
Membrane with multiple folds * -90 mv resting membrane potential * Maintained by sodium/potassium * nAChRs directly opposite
52
* N-ACHR
53
NACHR Subunit: Pentameric Unit
Penameric unit * 5 sub pores * Transmembrane
54
What happens to a NACHR subunit if ACH binds?
* Conformational change * Pores open, sodium/calcium/potassium flow
55
What happends to a NACHR subunit when NMBD binds?
* No conformational change * No ion flow * Probability of binding d/t concentration of NMBD vs Ach * Sch only requires binding at 1 alpha subunit ---- can leave 1 receptor and attach to other nACHRs ill hydrolyzed .....fasciculations
56
Name the only depolarizing NMBD in clinical practice
* Succinylcholine
57
Name (2) unique characteristics of Succinulcholine
1. Intense, rapid paralysis 2. Offset of effects prior to hypoxia
58
What is the main use of Succinylcholine
* Useful for tracheal intubation * Rapid sequence induction
59
Name (1) con of succinylcholine
* Releases histamine
60
Name the dose, onset and duration of Succinycholine
* I mg/kg IV * onset: 30 - 60 seconds * Duration: 3 - 5 minutes
61
MOA of Succinylcholine
* Attaches to 1 or both alpha subunits * mimics effects of ACh
62
Succinycholine: Hydrolysis is slower than Ach
* Sustained opening of receptor ion channels * Leakage of potassium ions = 0.5 mEq/liter serum increases
63
Succinylcholine Depolarization is called
* Phase 1 block
64
Succinylcholine: Phase 1 Block Characteristics
* ⬇️ contraction to single twitch stimulation * ⬇️ amplitude to continuous stimulation * TOF ratio > 0.7 * Absence of post-tetanic facilitation * Skeletal muscle fasciculations
65
Phase II Block
* Responses typical of non-depolarizing NMBD * Can be antagonized by anticholinesterase drug
66
Phase II Block: Abrupt transition
* SCh dose 2-4 mg/kg * Lack of/poorly functioning pseudocholinesterase * Relative “overdose”….desensitization
67
Phase II Block: Duration of Action
Normal: 3 - 5 minutes
68
Phase II Block: Hydrolyzed by butyrylcholinesterase (plasma cholinesterase)
* Synthesized in liver * Terminated by diffusion out of NMJ into plasma * Succinylmonocholine (less potent) and choline
69
Phase II Block: Pseudocholinesterase activity
* Decreased hepatic production (⬇️ 75% before apparent) * Drug-induced decreases (Neostigmine, Reglan, chemo, insectides) * Genetically atypical * Chronic diseases (renal): ↓ activity * Pregnancy (high estrogen levels): ↓activity * Obese: ↑ activity
70
Characteristics of Dibucaine
* Amide local anesthetic * Inhibits activity of normal variant butyrylcholinesterase (pseudocholinesterase) * % inhibition = dibucaine number
71
Dibucaine Numbers
* Reflects quality not quantity of enzyme * 20: SCh 1mg/kg lasts 3 hours
72
Side Effects of SCH
* Cardiac dysrhythmias * Hyperkalemia * Myalgia * Myoglobinuria * ⬆️ intragastric pressure * ⬆️ intraocular pressure * ⬆️ intracranial pressure * Masseter spasm
73
What can you do to prevent side effects of SCH?
* Pretreatment with non-depolarizing NMBD
74
Name (6) effects of Defasiculating d/t Patient symptoms
* Loss of visual focus * Mandibular muscle weakness * Ptosis * Diplopia * Dysphagia * Increased hearing acuity
75
name the (3) Cardiac Dysrhythmias w/ SCH
1. SB 2. JR 3. Sinus Arrest
76
Actions of cardiac muscarinic, cholinergic receptors w/ SCH
* Mimics action of ACh * Most likely on 2nd dose, 5 minutes post 1st * Due to metabolites: succinylmonocholine and choline???
77
SCH: Actions at ANS ganglia
* ⬆️ Heart rate and blood pressure * Mimics action of Ach * Usually occurs with large doses
78
Cause of Hyperkalemia with SCH
* Patient's with extrajunctional sites (more ion channels)
79
Name (5) conditions that can cause hyperkalemia in SCH use:
* Unrecognized muscular dystrophy Duchenne's: Diagnoseis 2-6 y/o * Unhealed 3rd degree burns * Denervation of skeletal muscles (atrophy): 96 hrs - 6 months * Skeletal Muscles trauma * Upper motor neuron lesions
80
Can you alter Hyperkalemia with pretreatment with non-depolarizers
No
81
Myalgia
* Young adults * Neck, back, abdomen * Confused with pharyngitis d/t intubation?
82
Myoglobinuria
Damage to skeletal muscles * Especially pediatrics * Usually found later to have MH or muscular dystrophy
83
Intragastric pressure and LES pressure with Succinylcholine
* Inconsistent increases r/t 1) intensity of fasciculations 2) direct increase in vagal tone
84
Is Intragastric pressure and LES pressure seen in children?
* Not seen in children d/t minimal fasciculations
85
Succinycholine: Intragastric pressure and LES pressure: Passage of gastric fluid into esophagus and pharynx
* Aspiration? * Some texts refute this concern stating gastric pressure doesn’t exceed LES pressure
86
Succinylcholine Intraocular pressure
* Maximum increase 2-4 minutes after administration * Lasts 5-10 minutes
87
Succinylcholine Intraocular Pressure: MOA
MOA unknown * Contraction of EOM and globe distortion * Resistance to outflow of aqueous humor and dilation of vessels
88
When is Succinylcholine counterindicated d/t intraoccular pressure?
* Open anterior chamber injury
89
Succinycholine: Intraocular Pressure controversial
* Efficacy of defasciculation controversial
90
Succinycholine: Intracranial Pressure increase with patients with......
* intracranial tumors or CHI * Not consistently observed in studies
91
Succinycholine: Intracranial Pressure Attenuated
* Attenuated by hyperventilation prior to SCh * RSI not ventilated
92
Succ: Sustained Skeletal Muscle Contraction
* Incomplete jaw relaxation/masseter muscle spasm * Inadequate dosage given? (children) * Early indicator of Malignant Hyperthermia?
93
Malignant Hyperthermia
Hereditary rhabdomyolysis associated with anesthetics * Muscle destruction * Hyperkalemia * Acidosis * Dysrhythmia * Renal failure * DIC
94
Malignant Hyperthermia: Triggers
* ALL volatile anesthetics * Succinycholine
95
Malignant Hyperthermia: Causes
* Mutations in skeletal muscle calcium release * Ryanodine receptor (RyR1) (1) 50-70% of MH patients (2)Native Americans
96
Maligant Hyperthermia: Ryanodine Receptors Mutations
*50-70% of MH patients *Native Americans
97
What is the Maligant Hyperthermia Test?
* Skeletal muscle caffeine contracture testing * Muscle biopsy
98
Symptoms of Malignant Hyperthermia
* Acute increased skeletal muscle metabolism * Increased oxygen consumption * Lactate formation * Heat production * Rhabdomyolysis
99
Signs of Maligant Hyperthermia
* ↑ ETCO2 * ↑ temp 1 degree C/5 minutes * Arrhythmias * Skeletal muscle rigidity
100
Treatment of Malignant Hyperthermia: ABCD (A)
* Agents- stop all triggering agents * Administer non-triggering anesthetics * Ask for help * Ask for MH Cart
101
Treatment of Malignant Hyperthermia: ABCD (B)
* Breathing - hyperventilation with 100% oxygen
102
Treatment of Malignant Hyperthermia: ABCD (C)
* Cooling procedures is patient is > 102.2
103
Treatment of Malignant Hyperthermia: ABCD (D)
* Dantrolene - continous rapid IV push
104
How much does dantrolene decrease mortality with MH?
* 80% --> 10%
105
Dantrolene Dose
* 2mg/kg IV * Respeat doses until symptoms subside or 10 mg/kg IV
106
Dantrolene MOA
* Inhibits calcium release into SR * By affecting the ryanodine receptors
107
Dantrolene Metabolism
* 5-hydroxydantrolene * Muscle relaxant properties * 50% c/o weakness…grip strength * Verapamil, Cardizem * Cardiovascular collapse
108
Most Common Side Effects with Dantrolene
* Weakness * Phlebitis * Respiratory failure * GI upset
109
Less Common side effects of Dantrolene
* Confusion * Dizziness * Drowsiness
110
NM Diseases: Myasthenia Gravis
Autoimmune Disease * Antibodies against Ach receptor * ↓ Ach receptors
111
Myasthenia Gravis: S/E
Increasing weakness/fatique * Diplopia * Ptosis * Extremity and respiratory muscle weakness * Tx: Cholinesterase Inhibitors
112
Myasthenia Gravis and Succinycholine
* Resistant to Sch… 1.5-2.0 mg/kg * fewer receptors….ED95 2.5 times higher
113
NM Disease: Lambert- Eton
Autoimmune diease * Small-cell lung cancer * Antibodies against calcium channels * Decreases release of Ach pre-junctionally
114
Lambert-Eton: Increases sensitivity
* Depolarizers * Non-depolarizers
115
NMB with the Chemical Classification of Amiosteroid
* Pancuronium * Doxacurium * Pipecuronium * Vecuronium * Rocuronium
116
NMB with Chemical Classification of Benzylisoquinoline
* Atracuronium * Cisatracurum * Mivacurium

Pharmacology Exam 3 (4 decks)

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