Written 09/17/2020; updated 11/14/2020; published online 04/30/2021
Ketamine is a versatile and powerful medication used for a variety of medical applications ranging from mild analgesia to general anesthesia. However, as the United States has continued to struggle with the role and power of law enforcement in society, due to recent high profile cases like the death of Elijah McClain, ketamine has become the center of an increasingly polarized debate, with some calling for a ban on its use in the prehospital environment and others defending the drug’s usefulness in the field. While ketamine has been proven to be a relatively reliable and effective drug in many cases, ultimately there is an increasing need to call into question the safety of ketamine in prehospital situations involving law enforcement. In order to rigorously analyze ketamine administration in emergency situations, this paper will characterize the debate around the drug, describe use cases and mechanisms of action, and review the data and complicating factors surrounding ketamine.
On the night of August 24, 2019, Elijah McClain, a 23-year-old African-American man, was walking home in Aurora, Colorado when he was confronted by police officers. Officers claimed that McClain was “acting crazy” and “definitely on something,” and subsequently placed McClain into a chokehold to render him unconscious. Medical responders that arrived on scene then administered ketamine after diagnosing excited delirium, and while en route to the hospital, McClain went into cardiac arrest (Tompkins, 2020). McClain was declared brain dead on August 27, 2019; the autopsy found that the manner of death was undetermined and could be due to multiple factors (Young, 2019).
Over the summer of 2020, as public calls for police accountability intensified after a string of high profile police brutality cases, the death of Elijah McClain has ignited a furious and polarized debate over the safety of using ketamine as a chemical restraint. On one hand, social media and news organizations often present ketamine as a dangerous recreational drug, with one article calling the drug a “known horse tranquilizer” and expressing horror that ketamine was being used in this way (Glenn, 2020). On the other hand, some medical professionals wholeheartedly disagree, viewing the drug as the ideal prehospital sedative and showing bemused confusion at the outrage over ketamine (Office of the Medical Director, 2020).
As with many debates, the truth more than likely lies in between the two extremes. Although it is true that the precursor to ketamine, phencyclidine, was considered too dangerous for human medical use, in recent decades, ketamine has been safely and widely adopted in the medical field as an analgesic and an anesthetic (Li & Vlisides, 2016). It is important to note, though, that this recent controversy centers around the use of ketamine not in a wider medical context, but specifically in emergency, prehospital situations. Given this, to refuse to reconsider the safety of ketamine when used in this way is at best a scientific miscalculation, and at worst, a blatant show of disdain for the public’s outrage over the injuries and deaths of people post administration of ketamine.
In reaction to the death of Elijah McClain, the Aurora City Council has recently agreed to put a temporary hold on the use of ketamine by paramedics, drawing support from the public but vocal criticism from some in the medical community (French, 2020). As the debate around ketamine continues to escalate, there is a need to take a careful look at how safe ketamine really is in prehospital settings, and how other factors may introduce uncertainty into the risks of ketamine administration. After all, to ban ketamine without proper justification would be to remove a potentially life-saving drug from the arsenal of emergency medical professionals, but to allow the use of ketamine despite injury and death would be to put patients in danger unnecessarily.
According to Rosenbaum, Gupta, and Palacios (2020), ketamine is a powerful and versatile drug with a wide array of applications within the medical field. At lower doses, ketamine acts as an analgesic with a rapid onset and a short duration of action; at higher doses, ketamine causes the patient to go into a dissociative state. It has proven to be safe and effective as a general anesthetic and a sedative for non-surgical procedures for patients older than three months. In addition to this, ketamine has been successfully used as an analgesic, and there is increasing research showing that ketamine could prove effective in treating depression and suicidal ideation; however, the Food and Drug Administration (FDA) has not specifically approved of the use of ketamine for analgesia or for depression. Outside of the medical environment, ketamine, known as “K” or “Special-K” in a more colloquial context, has gained a reputation as a recreational drug due its hallucinogenic and dissociative effects (Rosenbaum et al., 2020).
In an article published by Mion and Villevieille (2013), Ketamine is described as a medicine with an extensive variety of applications as an anesthetic, a sedative, an analgesic, and, more recently, an antidepressant. To produce its characteristic effects, ketamine interacts with N-methyl-D-aspartate (NMDA) receptors, opioid receptors, monoaminergic receptors, muscarinic receptors and voltage sensitive Ca²⁺ ion channels in the central nervous system. Ketamine is perhaps most widely known for its properties as a noncompetitive NMDA receptor antagonist. NMDA receptors are an ionotropic, glutamatergic receptor that is distributed throughout the central nervous system, and it plays an important role in learning and memory; inhibition of these receptors gives ketamine its hallucinogenic and dissociative properties (Mion & Villevieille, 2013). Ketamine’s mechanisms of action involving other receptors also contribute to its pharmacological properties, but a comprehensive review of its specific actions in the nervous system is beyond the scope of this paper. It should be noted, however, that there remains much to be studied about the effects of ketamine, and novel mechanisms are being suggested and discovered even today (Vesuna et al., 2020).
In a document published by Rosenbaum, Gupta, and Palacios (2020), the authors write that ketamine has been successfully used in the hospital for pain-relief, depression, and anesthesia, but it has been adopted for prehospital use as well, with most favorable results in military applications. Because it has a very rapid onset and a short duration of action, it has been hailed as an ideal sedative for emergency situations in the field. Its properties give medical providers a great amount of control over the level and duration of sedation, and under careful surveillance, life-threatening adverse reactions are not common. This does not mean that ketamine is without risk, however. There is a long list of side effects associated with ketamine, ranging from nausea to changes in blood pressure. Documentation warns that healthcare providers administering ketamine should always monitor patients and be ready to intubate should respiratory function decline. Another potential side effect is emergence phenomena, which can cause schizophrenia-like symptoms post ketamine administration (Rosenbaum et al., 2020).
Given that ketamine is such a strong medication with such potent effects on the nervous system, it makes sense that the decision to administer ketamine in a dynamic environment like the prehospital setting should include a careful consideration of its benefits and risks. When assessing patients for administration of any medication, healthcare providers always check for “indications” and “contraindications.” If patients meet the indications and do not have any of the contraindications, then the healthcare providers can administer medication with less potential risk for adverse reactions or drug interactions. The Vermont EMS “Ketamine Administration Resource Kit” (2018) introduces paramedics to the administration of ketamine and describes the indications and contraindications as follows. Indications include severe pain, behavioral emergencies, and excited delirium. Contraindications include but are not limited to a prior medical history of conditions in which a transient blood pressure rise is dangerous and sensitivity to ketamine. In many areas of the United States, administration of ketamine in the field must be cleared by medical control, a physician who provides guidance and orders for paramedics and EMTs. The typical dosing of ketamine is 4 mg/kg with maintenance doses of 100 mg/mL (“Ketamine Administration Resource Kit,” 2018). The information presented here represents only one agency’s ketamine guidelines, and these guidelines can vary drastically depending on the agency.
In 2016, a clinical trial by Cole et al. (2016) was conducted comparing 5 mg/kg of ketamine and 10 mg of haloperidol, another commonly used chemical restraint, in a prehospital setting where sedation was needed for severe agitation. The authors noted that prior studies indicate higher doses of ketamine were not strongly associated with higher rates of adverse reactions. The standard of care for the EMS system used in the trial was haloperidol, but for the study, paramedics were trained in administration of ketamine. For a period of 12 months, 64 patients were given ketamine and 82 were given haloperidol. In terms of time of onset, ketamine was far faster (5 minutes), than haloperidol (17 minutes). Additionally, 95% of ketamine patients had adequate sedation prior to admission to the hospital versus only 65% of haloperidol patients. However, ketamine also had a much higher complication rate. Patients that were given ketamine had a complication rate of 49%, while patients that were given haloperidol had a complication rate of 5%. In the ketamine group, the most common complications were hypersalivation, emergence reaction, vomiting, dystonia, laryngospasm, and akathisia. 39% of ketamine patients required intubation versus 4% of haloperidol patients. This difference in intubation rate is quite surprising; whether or not co-intoxication with alcohol played a role in the high intubation rates, this study shows that protecting a patient’s airway after administration of ketamine is of utmost importance. This clinical trial provides interesting data on the effects and potential complications of ketamine, but it is limited by the fact that the trials were neither blinded nor randomized (Cole et al., 2016). Other studies report comparable results, but also share similar limitations.
A discussion around ketamine must necessarily include excited delirium, as in the prehospital setting, ketamine is often used to treat patients who are severely or profoundly agitated, which in many cases, is labelled by healthcare professionals as a syndrome called “excited delirium.” Excited delirium is marked by agitation, distress, aggression, and sudden death, and risk factors include being male, young, overweight, and African American (Gonin et al., 2017). According to the Colorado Sun, medics in Colorado diagnosed 902 patients with excited delirium and treated it with ketamine over a two and a half year period; these data includes the case of Elijah McClain, who was given ketamine for excited delirium shortly before his death (de Yoanna & Solomon, 2020). In scientific and medical communities, though, there is a heated debate around what excited delirium even is. As stated by Gonin et al. (2017), there is no concrete, agreed-upon criteria for diagnosing excited delirium, and while most papers concur that excited delirium is an actual condition, there has been no consensus on the pathophysiology. Takeuchi et al. (2011) discusses this confusion over excited delirium, reporting that excited delirium does not appear in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) or the International Classification of Diseases (ICD-9), but, as reported by Hoffman (2009) it has been accepted by the American College of Emergency Physicians (ACEP) (Gonin et al., 2017; Hoffman, 2009; Takeuchi et al., 2011). This lack of information has been further complicated by the number of high profile cases of deaths in police custody ascribed to excited delirium.
Another important factor to consider in the analysis of the safety of ketamine is the relationship between police and EMS. One of the first things that a potential EMT or paramedic learns during their training is that personal safety comes first; without confirmation that a scene is safe, medical personnel should always call and wait for additional resources such as police and fire. Thus, due to this symbiotic relationship, the increasing scrutiny on police officers should also apply to medical personnel working with police officers, and recent controversy over ketamine administration is inextricably linked to the relationship between police and EMS. In her article, Varagur (2020) writes that just this year, a paramedic from Minnesota filed a lawsuit against police officers that pressured him to administer ketamine (Varagur, 2020). Healthcare personnel should always place patient advocacy before all else, but in situations where police are involved, pressure from police can push paramedics to sedate patients who would not otherwise need it. As a Minnesota-based lawyer quoted in the article written by Varagur (2020) explained, “police officers outsource the injections to paramedics, and paramedics can plausibly claim that arrestees were being ‘belligerent’ or that they presented ‘safety concerns’” (Varagur, 2020). As the clinical trial data showed, ketamine is a drug with a significant risk of complications, so ultimately, if paramedics choose to administer ketamine, they need to do so after careful consideration of the indications and contraindications, and they need to be prepared to provide additional care if the patient should need it. Police officers can say to paramedics that the patient is aggressive and agitated, but it is incumbent upon the medical professionals on scene to advocate for the patient and to analyze the medical status of the patient in an unbiased way. In a joint statement, the American College of Emergency Physicians and the American Society of Anesthesiologists emphasized the need for accurate patient assessment and adequate monitoring, stating that they “firmly oppose the use of ketamine or any other sedative/hypnotic agent to chemically incapacitate someone solely for a law enforcement purpose and not for a legitimate medical reason” (“American College of emergency physicians and American society of anesthesiologists issue joint statement on ketamine use,” 2020).
The debate over ketamine has intensified significantly in part because of the fight for racial justice, and given the racial biases in both policing and medicine, race is an important factor in the safety of ketamine that cannot and should not be ignored. For one, clinical trials for drugs are heavily biased towards white, young, male-identifying people, which can overlook how the drug may affect those who do not fall in that demographic (“Clinical Trials Have Far Too Little Racial and Ethnic Diversity,” 2018). Additionally, many healthcare workers have an implicit negative association with people of color. Medical biases like these in the healthcare system have proven effects in the patient outcomes for BIPOC patients in areas such as childbirth and emergency care (Hall et al., 2015). These biases may be exacerbated by the presentation of excited delirium. Without a clear criteria for how to diagnose excited delirium, healthcare professionals default to subjective symptoms like aggression and agitation. This leaves room for racial bias to influence the diagnosis, as studies have shown that Black, male-identifying people are stereotypically seen as more aggressive and angry (Lundberg et al., 2018). The added layer of the over-policing of people of color further complicates matters. If African Americans are less likely to be adequately covered in clinical trials, more likely to be diagnosed with excited delirium, and disproportionately overrepresented in police interactions, then there is a multiplier effect on any potential harms that may come from either the inherent risks of ketamine or the dangers of improper administration of ketamine in the prehospital environment. At this point in time, there is a distinct lack of sufficient national data on patient outcomes post ketamine administration in cases involving police, which is an issue that should be expeditiously addressed.
Ketamine is undoubtedly a potent, versatile drug with a place in the medical field. With its rapid onset and its short duration of action, it is certainly clear why many healthcare professionals consider it to be an ideal sedative and analgesic. But, this recent controversy and the resulting backlash against ketamine is also merited. In advocating for and ensuring the best possible outcomes for patients, it is important to take a careful look at ketamine and how it is used in the field. The lack of data surrounding excited delirium and ketamine administration in police altercations needs to be remedied in order to conclusively determine the safety of ketamine. In addition to this, it is not enough just to look at ketamine itself; it also needs to be considered with full context. A drug that is effective and safe in a hospital setting may not be as safe when used in the field, especially if patients cannot be monitored adequately due to police involvement. However, simply saying that ketamine is dangerous and calling for its removal from prehospital settings is also not necessarily the best solution. There are situations in which ketamine can improve patient care and even save lives, and to call ketamine a “horse tranquilizer” and to universally refer to its administration as barbaric is a bad faith argument that does not present the argument and body of evidence in its entirety. There should be more clear and effective communication between groups calling for the immediate end of ketamine use and groups universally praising ketamine’s benefits, as only then can society ensure the best possible patient outcomes. Ultimately, any review of ketamine by either the non-scientific or the scientific community needs to be acutely aware of how many diverse factors can affect the safety of ketamine and how the complexities of politics in America may bias data and analysis.
If you have any questions, comments, or suggestions, feel free to contact me at lauracao@usc.edu.