A 78-year-old male with advanced dementia presents
with a large incarcerated inguinal hernia. He is extremely confused, agitated and
combative. He is being physically violent and despite his age and weighing only 60 kg
he is requiring four theatre staff to prevent him from falling off the theatre table. He
has already kicked one theatre support worker and attempts to secure venous access
have failed, prompting further violent outbursts from the patient. It is your
judgement that he requires a rapid sequence induction but that he currently poses a
risk of harm to himself and others. It is your intention to provide sedation sufficient to tolerate intravenous cannulation whereupon you will pre-oxygenate and perform an
intravenous rapid sequence induction. You request ketamine, 100 mg/mL, which you plan to
deliver intramuscularly. Which one of the following is the most suitable
volume to administer?
a) 0.6mL
b) 1.2mL
c) 2.4mL
d) 4.2mL
e) 6.0mL
