Ketamine is used to sedate intubated patients. (Ie patients on ventilators).

So you know ketamine is in short supply right now

— Esther Choo MD MPH (@choo_ek) January 1, 2022

The drugs shown here, including ketamine, are what’s required to keep one person on a ventilator for 24 hours. The use of 3 or 4 simultaneous sedatives are required to keep a body from breathing against the ventilator machine and not deplete oxygen stores further. pic.twitter.com/2nuiGBMpgx

— Mark Read (@Read4Ks) January 2, 2022

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American Society of Health-System Pharmacists
Current Drug Shortages
12/13/2021
Ketamine Injection

Reason for the Shortage
AuroMedics has ketamine on shortage due to increased demand.
Hikma has ketamine injection on shortage due to increased demand.
Mylan Institutional divested ketamine to AuroMedics.
Par had Ketalar on shortage due to increased demand.
Pfizer has ketamine on shortage due to manufacturing delays.

ashp.org