Exam 3 Flashcards
What is usually the cause of ELMS?
Paraneoplastic syndrome related to lung cancer.
What are the anesthetic consideration in ELMS?
AChE inhibitors don’t have much of an effect. Much more sensitive to paralytics. Use NDMB & sugammadex as reversal, not succinylcholine.
How can ELMS be treated?
With 4,5 amino pyridine, which blocks the Ca2+ activated K+ channel –> prolonged depolarization. Or use TEA (Tetraethyl ammonium, a non-selective K+ blocker, only as last resort. Or plasmapheresis to filter out antibodies.
What happens in ELMS on the cellular level?
Antibodies attach & block the P-type Ca2+ channel –> decreased neurotransmitter release.
What is the difference between MG & ELMS S/S?
In ELMS the S/S get better with activity.
Where do ELMS S/S usually start and what are they?
Weakness in peripheral muscles & fatigue
What are the anesthetic considerations for MG?
Lower dose of NDMB, inhalation gases or sedation alone, or higher dose of Scc due to fewer receptors available.
What are the treatments for MG?
AChE inhibitors, Thymus gland removal, plasmapheresis
What test is used to diagnose MG?
Tensilon test, Give AChE inhibitor & if response gets better then positive for MG
What are later S/S of MG?
Larger muscle group weakness & eventually the diaphragm
What are some early signs of MG?
Small central weakness, droopy eyelids, double vision due to gaze muscles & gets worse throughout the day.
Which nACh receptor is not affected by paralytics?
The Neuronal ACh receptor. It has five 𝝰7 subunits
What happens in Myasthenia Gravis?
Auto immune antibodies attach to nACh receptor & destroys them
Why is the Adductor pollicis used to check paralyzation?
It gives a good indication of diaphragm function. The diaphragm recovers before the thumb.
What happens in a SCc phase 2 block?
The nACh receptors on the muscle do not work well.
What is the TOF target & what does that tell us?
Ratio of 0.9, means plenty of muscle function has returned to support own breathing.
Why is there a drop-off in TOF response in non-depolarizing blockers?
The 𝝰3β2 receptor is blocked
How is the TOF ration calculated & when is it used?
Last twitch divided by first twitch. Only used with non-depol blockers.
What is accommodation?
nACh receptors do not like interacting with SCc & will shut down with continuous administration.
What are 3 alternative locations for nerve stimulation?
Ophthalmic branch of facial nerve, Peroneal nerve, & Posterior tibial nerve
What is an EMG and what would an abnormal measurement mean?
Directly stimulate a muscle. If direct stimulation is better then there is a problem in the CNS.
What is an example to check for quantitative force?
Pressure transducer under the thumb
Which nerve stimulation would be used to recruit all motor units via all motor neurons?
Supramaximal Stimulus.
What is the reason to use tetanic nerve monitoring, how can one tell?
To check for residual NMJ blockage. The plateau would fall off if there is residual blockage.