Ketamine as an Induction Agent in Trauma Patients

Hemodynamic Advantages

The American Society of Anesthesiologists recommends ketamine for its ability to preserve blood pressure through endogenous catecholamine release, which is critical in trauma patients who may be hypovolemic or in shock 2, 3
Ketamine's sympathomimetic activity helps maintain cardiovascular stability, unlike propofol or thiopental, which can cause myocardial depression and vasodilation 4, 2
The Society of Critical Care Medicine recommends ketamine as a first-line induction agent alongside etomidate, with particular utility in hemodynamically unstable patients 1

Ketamine causes bronchodilation, which is beneficial in trauma patients who may have concomitant chest injuries, aspiration risk, or underlying reactive airway disease 2, 3
Thiopental can lead to severe bronchoconstriction in patients with preexisting asthma or in the presence of cholinergic stimulation, making ketamine a safer choice 4, 2

Administer ketamine at 1-2 mg/kg IV for RSI, using the lower end (1 mg/kg) in patients with cardiovascular compromise to minimize hemodynamic effects while maintaining adequate sedation 1
Always administer ketamine before the neuromuscular blocking agent to prevent awareness during paralysis 1

Despite sympathomimetic properties, ketamine can cause paradoxical hypotension in critically ill patients with depleted catecholamine stores, such as those in prolonged shock, severe cardiogenic shock, or adrenal exhaustion 1, 5
Ketamine increases upper airway secretions, which can be attenuated with atropine or glycopyrrolate pretreatment, particularly important in trauma patients at risk for aspiration 2, 3

Etomidate has minimal cardiovascular effects but causes transient adrenal suppression and is explicitly contraindicated in pediatric septic shock 1
Propofol causes myocardial depression and vasodilation even in euvolemic patients and should be employed with extreme caution in trauma casualties 2, 3
Thiopental can cause severe bronchoconstriction and requires cautious use with fluid infusion and vasoactive drugs 4, 2

In head-injured patients, ketamine is safe and appropriate for RSI, particularly when used with controlled mechanical ventilation, as historical concerns about increased intracranial pressure have been refuted by evidence from 2009-2013 5
In hemodynamically unstable trauma, use the lower ketamine dose (1 mg/kg) to minimize risk of paradoxical hypotension while maintaining adequate sedation 1