NMBD

Question 1

Succinylcholine  
Onset 
Dose 
CI 
ADE

Answer 1

Onset 45-120  (30-60) seconds  
Duration approx 10min
Dose 
RSI 1-1.5 mg/kg 
1.5-2 mg/kg if co-admin with roc (defasiculating dose, 0.03mg/kg)
Pedi 
Neo-infant 3-4mg/kg 
Child 2mg/kg 
IM 4mg/kg
1:3000 homozygous abnl plasma cholinesterase = paralysis 3-8hrs 

Can increase k by 0.5 meq
Conditions with upregulated ach-R; burn injuries (24-48hrs later), muscular dystrophy, myotonias, prolonged immobility, crush injury, upper motor neuron dz (stroke, tumor) - risk of hyper K arrest
Brady in kids
Anaphylaxis 1:5000-10,000

Question 2

Rocuronium
Dose
Onset
Duration

Answer 2

Onset: 3-5 (1.5-2) min
Dose: 0.6-1.2 mg/kg 
*1 to 1.2 will have onset similar to sux  
Pedi 
Infant .25 mg/kg 
Children 0.4 mg/kg
Duration 30-40 
Maintenance 0.1-0.2 mg/kg
Defasciulating 0.03mg/kg

Question 3

Nondepolarizing

Answer 3

Competitive inhibitors
Classes:
Benzylisoquinolinium = “-urium”
-Hoffman Elimination; renal and hepatic sparing
-cisatricurium, atracurium, mivacurium, d-Tubocurarine
-histamine release; d-T&raquo_space; atracurium and mivacurium
Aminosteroids= “-onium”
-pancuronium, vecuronium, roc
-vagolytic; panc > roc > vec

Most common are intermediate duration
-Roc, Cis, Vec

Question 4

Vecuronium
Dose
Onset
Duration

Answer 4

0.1-0.2mg/kg 
3-4min 
Duration to 25% recovery 
30-45min 
Maintenance 
0.01-0.02mg/kg

Question 5

Cisatracurium
Dose
Onset
Duration

Answer 5

0.15-0.2 mg/kg
5-7 min
35-45 min
Maintenance 0.03mg/kg

Question 6

Monitoring

Answer 6

Train-of-four (TOF)
Look at # and ratio btwn 4th and 1st
TOF 0.9 and/or 5 seconds of sustained tetanus indicates full recovery
Surgical relaxation can be achieved when PT has 2-3 twitches

Question 7

Muscle Blockade Variability

Answer 7

Most resistant to most sensitive
Vocal cords > diaphragm > corrugator supercilii > abs > adductor pollicis > pharyngeal
***pharyngeal muscles are one of the last to recover

Question 8

Reversal

Answer 8

Acetylcholinesterase inhibitors
Can paradoxically slow recovery if given too soon…wait for 4 twitches?
Vagal side effects; Brady, GI stim, bronchospasm - always give with anticholinergics

Neostigmine + glcopyrolate (20% neo dose)
40-50 mcg/kg
I.e 3mg neo 0.6 glyco
Pedi dose is 30-40% less aka 20-40mcg/kg
With 20mcg/kg atropine or 10 mcg/kg glyco

Note physostigmine crosses BBB and can tx atropine toxicity

Assoc with PONV?

Question 9

Sugammadex

Answer 9

Selective relaxant binding agent (SRBA)
Reverses roc and vec

Dose not cross placenta

Dose
Cannot intubate, Connor ventilate; 16mg/kg
Deep reversal 4mg/kg
Standard 2mg/kg

Caution
Non hormonal contraceptives next 7 days 
Avoid with severe renal insufficiency 
Increased APTT/PT by 25% for 1hr 
Don't mix with; zofran, verapamil, ranitidine 
Anaphylaxis 0.3%

Question 10

Pearls

Answer 10

Dz sensitive to six:
-SLE, myositises

Dz resistant to non-depolarizers
-Burns. SCI, CVA, prolonged immobility, MS, CP
Dz sensitive
-Myasthenia, lambert-eaton, ALS, SLE, myositises, GBS, muscular dystrophy

Factors enhancing block
-volatile anesthesthetics, aminoglycosides, tetracycline, clinda, Mg, local anesthetics, CCBs, Lasix, dantrolene, Li, anticonvulsants, sux, hypokalemia, hypothermia, ketamine