Thank you for being a listener of The Elective Rotation – a Critical Care and Hospital Pharmacy Podcast. I am celebrating 4 years of this podcast, and it is 100% supported by listeners just like you.
Unlike many other professional resources, there are no third-party sponsors or advertisers on this podcast, at pharmacyjoe.com, or in my emails to you, and there never will be. This ensures the podcast and website remain unbiased, free from the influence of the pharmaceutical industry, and focused on helping hospital pharmacists in their practice.
I want to thank you for your continued support of the show whether you share these episodes with a colleague, join the Hospital Pharmacy Academy, or order a copy of my book A Pharmacist’s Guide to Inpatient Medical Emergencies.
In this episode, I’ll discuss the paradox of steroids in rapidly worsening myasthenia gravis.
Rapidly worsening myasthenia gravis with respiratory muscle weakness is a precursor to respiratory failure and myasthenic crisis.
Treatment of myasthenic crisis involves ventilatory support and a rapid-acting therapy such as plasmapheresis or IVIG. Because these rapidly acting therapies do not last indefinitely, high dose glucocorticoid therapy is also started as an immunomodulating therapy. The glucocorticoids start to provide benefit in a few weeks, about the time that effects wear off from plasmapheresis or IVIG.
Unfortunately, glucocorticoids are also on the list of cautionary medications that may worsen myasthenia gravis. Glucocorticoids may cause increased weakness of respiratory muscles and could tip a patient with rapidly worsening myasthenia gravis into respiratory failure. Early case series estimate the effects of glucocorticoids could lead to the need for mechanical ventilation in up to 10% of patients and up to 50% could have significantly worsened symptoms.
The negative effects of glucocorticoids in rapidly worsening myasthenia gravis are blunted if the patient is first started on rapid-acting therapy such as plasmapheresis or IVIG.
Orders for IVIG and glucocorticoids are often placed simultaneously, and glucocorticoids are more readily available compared to IVIG. This presents a risk of patients in myasthenic crisis receiving glucocorticoids before IVIG. This is not a concern if the patient is already being mechanically ventilated.
However, if the patient is not yet intubated there is a theoretical risk that starting the steroids first could cause the need for intubation when it would have otherwise been avoidable. This risk may be very small as the transient worsening from glucocorticoids may take several days to manifest. However, because the benefit of glucocorticoids in myasthenic crisis is delayed by several weeks, it makes sense to delay the start of glucocorticoids until after IVIG or plasmapheresis has begun.
Pharmacists are in a key position to ensure that glucocorticoids are started after IVIG or plasmapheresis as they can inform clinicians at the bedside of administration order and facilitate the prompt availability of rapid-acting therapies such as IVIG.
To get access to my free download area with 20 different resources to help hospital pharmacists in their practice go to pharmacyjoe.com/free.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.