Ketamine-induced Changes in Blood Pressure and Heart Rate in Pre-hospital Intubated Patients

Abstract

When a patient experiences trauma, pre-hospital rapid sequence intubation (RSI) is often the course of action. While RSI is associated with favorable neurological outcomes among traumatic brain injury patients, it also carries the risk of increased hypotension and bradycardia. Ketamine is a fast-acting anesthetic agent used in RSI, attractive due to its ability to raise heart rate (HR) and blood pressure (BP) and thus potentially lessening the severity of RSI-related hypotension and bradycardia. However, research in support of its use is inconclusive, with different studies reporting increases or decreases in BP and HR after ketamine administration. To study the effect of ketamine on HR and BP during RSI, we analyzed the data obtained from 1,516 patients who received trauma and non-trauma medical care including RSI from first responders and emergency personnel using two different statistical methods. We determined if there was any association between the vital signs prior to administration of ketamine and outcomes such as bradycardia and/or hypotension post-ketamine administration in patients undergoing RSI. We found that the vital signs prior to administration of ketamine (i.e. BP and HR) predict the development of bradycardia and/or hypotension in patients undergoing RSI and the relationship between baseline vital signs and the development of bradycardia and/or hypotension is moderated by the dose of ketamine. Results obtained from this study may help responders and emergency care personnel to identify the patients that are likely to benefit from ketamine as an anesthetic agent.