Corticosteriods in short supply
The TGA has requested ANZCA produce a safety alert, specifically to alert clinicians who may be administering corticosteroid medications into the epidural space. Owing to a lack of advice, consensus or specific guidance, there may be specific concerns for the available TGA-listed products.
Corticosteroids currently constrained in supply within Australia are:
- Dexamethasone 4 mg/mL product. This non-particulate steroid usually does not contain a sulfite preservative. The replacement product, S19A dexamethasone (Mylan) 4 mg/mL, is considered unsuitable for epidural administration due to the presence of preservatives (parabens), although the risk from the preservatives arises from inadvertent intrathecal injection rather than epidural placement per se.
- Celestone Chronodose (betamethasone 5.7 mg in 1 mL). This is a suspension (particulate-based) corticosteroid formulation. It contains two betamethasone salts (one soluble and one insoluble), which introduces the potential for the product to be considered a ‘partial suspension’.
Known risks are associated with the practice of epidural administration of corticosteroids. In 2014, the US Food and Drug Administration (FDA) released a safety warning that injection of corticosteroids into the epidural space may result in rare but serious adverse events, including loss of vision, stroke, paralysis, and death. Specific guidance is lacking for clinicians in identifying and managing these risks, i.e., practical guidance on how certain controls can/should be applied. There appears to be no therapeutic advantage to using particulate vs non-particulate steroids.
In 2020, The Australian and New Zealand College of Anaesthetists (ANZCA) and Faculty of Pain Medicine (FPM) Acute Pain Management: Scientific Evidence 5th Ed was published. The document provides recommendations for certain situations when epidural corticosteroid injection may be considered. Whilst dexamethasone is the corticosteroid most often referred to, this publication is ‘silent’ on which product(s), or formulation(s), is suitable.
In 2015, a consensus statement, developed in the US in collaboration with the FDA, was published: Safeguards to Prevent Neurologic Complications after Epidural Steroid Injections. The statement recommends epidural administration of corticosteroids in certain circumstances; however, it assumes controls are in place to minimise the risks including:
- Avoiding particulate corticosteriods (suspensions).
- Anatomic considerations.
- The use of radiographic guidance, and/or
- Administration of a lower risk substance (e.g., local anaesthetic) into the epidural space prior to particulate corticosteriod administration.