In this episode, I’ll discuss mannitol extravasation.
When given as a bolus, mannitol is an osmotic diuretic that does not cross the blood-brain barrier. Mannitol lowers intracranial pressure by osmotically drawing free water out of the brain and into circulation where it can be eliminated. If given as a continuous infusion, mannitol will eventually cross the blood-brain barrier and have no effect on intracranial pressure.
This osmotic effect means that if even a small amount of mannitol extravasates, it can pull a large volume of free water with it and quickly turn into compartment syndrome.
Serious consequences of mannitol extravasation have been reported, including compartment syndrome in a patient’s forearm that required surgical treatment.
A case report in the journal Anesthesia and Analgesia describes the successful use of hyaluronidase to prevent complications from mannitol that had extravasated into a patient’s hand.
…150 units of hyaluronidase was mixed in 10 mL of normal saline. Using a 25-gauge needle, multiple subcutaneous injections of 0.5–1.0 mL were performed around the periphery of the extravasation…
…The hand was examined every hour. The swelling diminished after 6 h and was completely resolved by the next day.
Members of the Hospital Pharmacy Academy have access to a practical training from a pharmacist’s point of view about the management of extravasation of medications, in addition to hundreds of other practice resources. From the time of this recording until 10 pm EST on Tuesday, April 25, you can get a special recurring quarterly membership of 3 months for the price of 2 to the Hospital Pharmacy Academy. To get immediate access, go to pharmacyjoe.com/quarterly. Current monthly members of the Hospital Pharmacy Academy can also access this discount by going to their member profile page at pharmacyjoe.com/profile.
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