We’ve previously mentioned total ketamine anaesthesia in our post on war surgery, using a simple i.v. drip. Today, I talked to a friend and colleague of mine with extensive experience from MSF (Médecins sans frontières – Doctors without borders). Here’s his handy tips on ketamine infusion anaesthesia in the developing world.
Ketamine i.v. drip infusion
Mix 500mg of Ketamine in a bag of 500 mL saline, to get ketamine 1 mg/ml. Get the patient’s weight in kilograms. Let the starting point for your maintanence dose of ketamine i.v. drip infusion be [the patient's weight i kg] drops per minute. This will equal around 4 mg/kg/hr. Adjust to effect.
Ketamine induction cocktail
You will still need an induction dose of ketamine 1-2 mg/kg i.v. For children (or grown-ups) where you can’t easily get i.v. access while they’re awake, you can use a dose of ketamine 5-8 mg/kg i.m. for induction. You can also mix in atropin and a little midazolam in the same i.m. syringe to give them the full cocktail i.m. induction.
Remember, while ketamine is probably the most stable among any of the quick acting induction agents we have, ketamine still needs to be dose adjusted for bled-out, unstable patients. And, obviously, tips like these are not medical advice, but a tip to be used at your own discretion and with your own clinical judgement. Anyway, thanks for the tips, Jonas!