Acetylcholinesterase Inhibitors in Myasthenic Crisis: A Systematic Review of Observational Studies

Abstract

Current myasthenia gravis guidelines recommend intravenous immunoglobulin or plasmapheresis and discontinuation of pyridostigmine during myasthenic crisis. However, intravenous immunoglobulin or plasmapheresis is expensive and frequently not available in developing countries. This study aims to summarize the evidence of giving an acetylcholinesterase inhibitor in myasthenic crisis. Medline, Embase, and Cochrane databases and references were searched for observational studies that determined the use of acetylcholinesterase inhibitor in myasthenic crisis. The eligibility criteria were as follows: population, patients with myasthenic crisis, intervention (acetylcholinesterase inhibitor administration), and outcome (clinical improvement and complications). In total, 106 studies were identified, 92 through database searching (after removing duplicates) and 14 through other sources. Only eight were analyzed in the present systematic review. In five, acetylcholinesterase inhibitor was given at the start of the crisis, whereas in the other three, acetylcholinesterase inhibitor was discontinued initially and then restarted prior to extubation. Two observational analytic studies and three case reports showed improvement in different outcome measures. In the other three, improvement of outcome measures was also observed. Overall, a small proportion of patients developed cardiac arrhythmia and pneumonia after administration of acetylcholinesterase inhibitor alone, although this was not statistically different compared with those subjected to plasmapheresis. In summary, continuous intravenous infusion of pyridostigmine or neostigmine can be a substitute for intravenous immunoglobulin or plasmapheresis if these are not available during crisis; however, caution should be observed because of the aforementioned possible complications.

Exploring the Binding Pattern of Geraniol with Acetylcholinesterase through In Silico Docking, Molecular Dynamics Simulation, and In Vitro Enzyme Inhibition Kinetics Studies

“…Therefore, cholinesterase inhibitors are used to maintain acetylcholine levels in synapses and enhance cholinergic transmission [ 1 , 5 ]. This excess of acetylcholine in synapses leads to increased stimulation of muscarinic and nicotinic receptors, which provide therapeutic relief for memory deficits in AD [ 6 , 7 ], muscle weakness in MG [ 8 , 9 ], and gait dysfunction in PD [ 10 ].…”

Review of Possible Therapies in Treatment of Novichoks Poisoning and HAZMAT/CBRNE Approaches: State of the Art

“…The current pretreatment procedure is 30 mg every 8 h [ 55 ]. Pyridostigmine can be given orally (liquid or pill), intramuscularly or intravenously as injections to patients who cannot take oral drugs [ 57 ]. Pyridostigmine has been approved for military use by the FDA as a pretreatment to the GD [ 58 ].…”

Current Treatment of Myasthenia Gravis

“…It is suggested to discontinue AChE inhibitors in patients with MG crisis requiring mechanical ventilation support, due to concerns of increased bronchial secretion and bronchospasm, with a goal of restarting them during the waning process or after extubation. An intravenous preparation of pyridostigmine (1 mg IV equivalent to 30 mg PO) may be considered in selected settings where intravenous immunoglobulin or plasma exchanges are unavailable, but caution is needed as there may be an increased risk of cardiac arrythmia [ 33 , 34 ]. Side effects are either due to stimulation of the ACh muscarinic receptors, which include gastrointestinal disturbances (abdominal cramps, diarrhea, nausea, increased salivation), increased bronchial secretions, lacrimation, hyperhidrosis and bradycardia, or stimulation of nicotinic receptors, including muscle cramps, and fasciculations.…”