No abstract

Myasthenia gravis (MG) is an autoimmune disorder resulting from the production of antibodies against acetylcholine receptors leading to the destruction of the postsynaptic membrane at the neuromuscular junction. In the US there are about 18,000 people with MG. Myasthenia gravis crisis (MGC) is defined as any MG exacerbation necessitating mechanical ventilation. Most patients presenting with MGC have an identifiable risk factor. The diagnosis of MGC should be suspected in all patients with respiratory failure, particularly those with unclear etiology. Acute management of MGC requires supportive general and ventilatory therapy and institution of measures to improve the neuromuscular blockade. The latter includes plasma exchange or i.v. immunoglobulin, and removal of the offending trigger. The outcome of patients with MGC has improved significantly and the current mortality rate is about 4 to 8%.

Current pharmacological therapy for Alzheimer's disease (AD) includes the cholinesterase inhibitors (ChEIs) donepezil, rivastigmine, and galantamine and the N-methyl D-aspartate receptor antagonist memantine. Based on the results of randomized controlled trials and several meta-analyses, ChEIs appear to show modest but statistically significant improvements on several measures, including cognition and global functioning. Given their modest effects, there is a lack of consensus among clinicians regarding issues related to initiation, optimal duration, and discontinuation of ChEI therapy across the spectrum of AD. There is evidence from long-term observational controlled studies that early initiation and persistent exposure to AD therapy lead to delays in nursing home admission and significantly slower rates of cognitive and functional impairment. In the moderate to severe stages of AD, therapeutic trials of higher dose ChEIs and the addition of memantine are recommended for patients who are no longer responding to lower doses. While side effects are generally mild and gastrointestinal in nature, these events can lead to significant morbidity in more susceptible patients with advanced disease. Patients should thus be regularly monitored for any potential serious side effects of ChEI therapy, which also may include syncope and bradycardia. At the terminal stages of AD, such as when patients become hospice eligible, attempts to cautiously discontinue all medications not necessary for quality of life, including AD drugs, should be made.

In critically ill acute ischemic stroke patients, institution of a dedicated NCT was associated with a reduction in resource utilization and improved patient outcomes at hospital discharge. Several factors including improved patient care protocols may explain this association.