Rapid Agitation Control With Ketamine in the Emergency Department: A Blinded, Randomized Controlled Trial

A Comparison of Ketamine to Midazolam for the Management of Acute Behavioral Disturbance in the Out-of-Hospital Setting

STUDY OBJECTIVE

Acute behavioral disturbance is characterized by altered mental status and psychomotor agitation. Pharmacological sedation may be required, risking potential respiratory compromise. We compared the need for emergent airway support following administration of midazolam or ketamine to treat acute behavioral disturbance in the out-of-hospital setting.

METHODS

In this retrospective cohort study of patients with acute behavioral disturbance in an urban emergency medical service system between 2017 and 2021, we compared the likelihood of out-of-hospital advanced airway management following administration of midazolam or ketamine. Advanced airway management was defined as out-of-hospital endotracheal intubation or supraglottic airway insertion.

RESULTS

Among 376 eligible patients, the median age was 35, and 78% were men. The most common etiologies of acute behavioral disturbance were substance use (51%), trauma (18%), and presumed postictal agitation (11%). In all, 162 patients (43%) initially received midazolam and 214 (57%) ketamine. The frequency of advanced airway management was similar between these respective groups (12% [n=19] versus 11% [n=24], difference 0.5%, 95% CI -6.0% to 7.0%). Adjusted for potential confounders, the odds of receiving advanced airway management did not differ between midazolam and ketamine (aOR 1.02, 95% CI 0.44 to 2.38), and no differences were observed in emergency department intubation rates (14% in midazolam recipients, 11% for ketamine) or overall mortality (2% in midazolam recipients, 1% for ketamine).

CONCLUSION

In this cohort study of patients with acute behavioral disturbance, emergent airway support and other outcomes did not differ following out-of-hospital treatment with midazolam or ketamine.

Ketamine: An emerging agent in the management of neuropsychiatric disorders

Ketamine's unique pharmacological profile, safety, modulation of multiple neurotransmitter systems, and ability to produce neuroplastic changes make it a subject of study with implications for a wide range of neuropsychiatric disorders beyond its traditional use as an anesthetic agent. This article aims to provide an overview of the pharmacology of ketamine and briefly discuss its emerging use in treating: substance use disorders (alcohol, cannabis, cocaine, and opioids); withdrawal syndromes (opioid and alcohol); acute and chronic pain syndromes; and severe psychomotor agitation. Ketamine for the treatment of depression and suicidality is well established; however, the focus of this paper is to outline less common indications.

Chronotherapeutic considerations of benzodiazepine administration for agitation management in the emergency department

OBJECTIVE

Agitation in the emergency department (ED) affects up to 2.6% of encounters, posing significant risks to patients and caregivers. This review investigates the impact of circadian rhythms on benzodiazepine (BZD) pharmacokinetics and pharmacodynamics, focusing on how dosing time influences outcomes in managing acute agitation.

METHODS

A comprehensive literature search was performed using PubMed and Google Scholar (updated April 2024) to identify studies on BZD use in adult ED patients for acute agitation. Search terms included "antipsychotic agents," "lorazepam," "midazolam," "diazepam," and "emergency service." Studies focusing solely on substance intoxication were excluded. Priority was given to double-blind clinical trials, while open-label studies were included if no double-blind data were available. Referenced citations from identified publications were also reviewed.

RESULTS

Twenty-nine studies met the inclusion criteria: 16 randomised, double-blinded placebo-controlled trials, 5 prospective open-label studies and 8 retrospective reviews. Of these, 22 studies either did not report the time of day of patient recruitment or recruited patients over a year-long time frame. Four studies that specified the time of day of patient recruitment suggested a possible circadian variation in BZD sedation efficacy. Additionally, three studies that reported recruitment months revealed potential seasonal patterns in sedation requirements and efficacy.

CONCLUSIONS

Circadian rhythms appear to influence BZD metabolism and therapeutic effects, which could have implications for optimising treatment strategies. Aligning BZD dosing schemes with biological timing may enhance treatment outcomes and minimise adverse effects. Further research is needed to validate these findings and develop personalised chronopharmacotherapy strategies for acute agitation in the ED.

Ketamine Versus Haloperidol/Lorazepam/Diphenhydramine Combination Treatment for Management of Acute Agitation in the Emergency Department

Purpose

Appropriate use and timing of agents for chemical management of patient agitation is critical for the safety of patients and providers. Ketamine may have a preferable safety profile in acutely agitated patients, especially those with an unknown medication history given that it does not carry the same cardiovascular and respiratory risks as other sedative agents currently used in practice. This study aimed to evaluate subsequent chemical sedation requirements and the incidence of adverse events following the use of ketamine for agitation as compared to combination antipsychotic/sedative use in the ED.

Methods

This was a retrospective, single-center, observational cohort study of 102 adult patients who received chemical sedation for agitation/aggression/combative behavior from January 2018 to December 2023 at the Mount Sinai Medical Center Emergency Department. Patients who received at least one dose of ketamine (n = 51) were compared to patients who received at least one dose of the B52 combination (diphenhydramine (Benadryl) 25 mg, haloperidol (Haldol) 5 mg, and lorazepam (Ativan) 2 mg) (n = 51) for management of aggression. The primary endpoint was restricted mean survival time (RMST) to next sedative given. Secondary endpoints included the number of additional sedatives needed, adverse events, and length of stay.

Results

The use of ketamine was associated with patients requiring additional sedation both more often and sooner than patients who received the B52 combination (RMST to next sedative: 2.1 hours ketamine vs 4 hours B52; p = 0.032, median additional doses: 3 doses ketamine group vs 0 doses B52 group; p < 0.00).

Conclusion

In agitated patients within the ED, the administration of ketamine demonstrated inadequate duration of sedation and increased need for supplemental sedative use compared to B52.

Agitation: Neurobiology and current management guidelines

There have been important updates in the guidelines for the management of agitation in emergency room settings, including psychiatric emergency services. This manuscript provides a synthesis of current recommendations, combined with a detailed breakdown of the neurobiology of agitation, linking these neuroscientific dimensions with the pharmacological profiles of the drugs recommended by practice guidelines (as well as the profiles of other important agents). Since Project BETA (Best Practices in Evaluation and Treatment of Agitation) guidelines were published in 2012 (by the American Association for Emergency Psychiatry), there have been several developments in the standard of care, including an increase in use of ketamine and droperidol. Recommended treatment strategies for clinicians will be presented, including consideration of how to address specific causes of agitation.

Recent trends and risk factors for chemical and physical restraint use in the emergency department evaluation and treatment of trauma patients

BACKGROUND

Despite research linking chemical and physical restraints to negative outcomes including unplanned intubations and psychological distress, there is little guidance for their use in the care of trauma patients. We used institutional data to describe recent trends in chemical and physical restraint in the emergency department evaluation and treatment of trauma patients and to identify characteristics associated with their use.

METHODS

This study includes adult trauma activations at a United States urban level I trauma center from January 2016 to July 2022. Data were collected from the trauma registry and medical record. We assessed the use of chemical restraints and physical restraints during care provided in the trauma resuscitation bay and emergency department. We assessed trends over time graphically and with logistic regression. We used multivariable regression models to evaluate associations between restraint use and patient and clinical characteristics and the outcomes of ICU admission, hospitalization duration, and mortality.

RESULTS

Of the 8,112 patients, most were male (74.8 %), White (55.8 %), and privately insured (35.2 %). Overall, 8.1 % were restrained with 7.1 % chemically restrained and 2.7 % physically restrained. Overall restraint use increased 254 % (p < 0.001) from 2016 to 2022 driven primarily by a 460 % (p < 0.001) increase in chemical restraint use including a 630 % increase in ketamine administrations (p < 0.001). Use of restraints was associated with pre-existing psychotic disorders, intoxication, altered mental status, increasing injury severity, and Medicaid insurance (p < 0.001). Chemical restraint administration was associated with a 3.5 percentage point (95 %CI 1.1-5.9; p = 0.004) increase in the probability of ICU admission and a 1.0 day (95 %CI 0.6-1.4; p < 0.001) increase in hospitalization duration.

CONCLUSIONS

In this institutional study, nearly one-in-twelve trauma patients were restrained during emergency department evaluation and treatment. Restraint utilization increased during the study driven primarily by increases in ketamine and restraints utilized during trauma bay evaluation and resuscitation. Future research should assess the generalizability of these findings. It is important that rigorous guidelines are established to ensure the safe and effective use of restraints in trauma.

Systematic review of parenteral ketamine for managing acute agitation in emergency settings

INTRODUCTION

Agitation, a significant psychiatric issue often linked to conditions like schizophrenia, bipolar disorder, and major depression, invariably pose challenges in emergency settings. Acute agitation occurs in 2.6 % of emergency cases and up to 12.2 % among patients with schizophrenia or bipolar disorder. With limited available options for effective management of acute agitation, ketamine is emerging as a fast-onset alternative to antipsychotics like haloperidol.

METHODS

This systematic review, following PRISMA guidelines, searched databases in April 2024 for studies on parenteral ketamine for acute agitation in emergency settings. Data extraction included patient demographics, ketamine administration details, sedation time, need for additional doses, adverse events, and intubation rates.

RESULTS

The search yielded 7410 results, narrowing to 29 suitable studies with 1516 patients (mean age 35.5 ± 12.4 years, 67.9 % male). Ketamine was administered intramuscularly (IM) in 69 % of studies, intravenously (IV) in 6.9 %, and either IV or IM in 24.1 %. Most patients (86.5 %) received IM ketamine at a mean dose of 3.83 ± 1.07 mg/kg, while 13.5 % received IV ketamine at 2.09 ± 1.56 mg/kg. Sedation occurred on average in 6.1 min. However, 24.5 % needed rescue medications or additional doses. Adverse effects included tachycardia (5.1 %), hypertension (5.5 %), hypersalivation (5.6 %), nausea (2.1 %), emergence reactions (1.4 %), and, rarely, cardiac arrest (0.2). While 19.1 % required intubation, the reasons for the same could not be attributed to ketamine exclusively. Furthermore, there was no evidence for worsening or development of psychotic symptoms with ketamine.

CONCLUSION

This review highlights the effectiveness and safety of parenteral ketamine for managing acute agitation in emergency settings. However, further research is needed to optimize ketamine use in this challenging scenario.

Fixed dose ketamine for prehospital management of hyperactive delirium with severe agitation

INTRODUCTION

Patients exhibiting signs of hyperactive delirium with severe agitation (HDSA) may require sedating medications for stabilization and safe transport to the hospital. Determining the patient's weight and calculating the correct weight-based dose may be challenging in an emergency. A fixed dose ketamine protocol is an alternative to the traditional weight-based administration, which may also reduce dosing errors. The objective of this study was to evaluate the frequency and characteristics of adverse events following pre-hospital ketamine administration for HDSA.

METHODS

Emergency Medical Services (EMS) records from four agencies were searched for prehospital ketamine administration. Cases were included if a 250 mg dose of ketamine was administered on standing order to an adult patient for clinical signs consistent with HDSA. Protocols allowed for a second 250 mg dose of ketamine if the first dose was not effective. Both the 250 mg initial dose and the total prehospital dose were analyzed for weight based dosing and adverse events.

RESULTS

Review of 132 cases revealed 60 cases that met inclusion criteria. Patients' median weight was 80 kg (range: 50-176 kg). No patients were intubated by EMS, one only requiring suction, three required respiratory support via bag valve mask (BVM). Six (10%) patients were intubated in the emergency department (ED) including the three (5%) supported by EMS via BVM, three (5%) others who were sedated further in the ED prior to requiring intubation. All six patients who were intubated were discharged from the hospital with a Cerebral Performance Category (CPC) 1 score. The weight-based dosing equivalent for the 250 mg initial dose (OR: 2.62, CI: 0.67-10.22) and the total prehospital dose, inclusive of the 12 patients that were administered a second dose, (OR: 0.74, CI: 0.27, 2.03), were not associated with the need for intubation.

CONCLUSION

The 250 mg fixed dose of ketamine was not >5 mg/kg weight-based dose equivalent for all patients in this study. Although a second 250 mg dose of ketamine was permitted under standing orders, only 12 (20%) of the patients were administered a second dose, none experienced an adverse event. This indicates that the 250 mg initial dose was effective for 80% of the patients. Four patients with prehospital adverse events likely related to the administration of ketamine were found. One required suction, three (5%) requiring BVM respiratory support by EMS were subsequently intubated upon arrival in the ED. All 60 patients were discharged from the hospital alive. Further research is needed to determine an optimal single administration dose for ketamine in patients exhibiting signs of HDSA, if employing a standardized fixed dose medication protocol streamlines administration, and if the fixed dose medication reduces the occurrence of dosage errors.

Management of the Agitated Patient

The acutely agitated patient should be managed in a step-wise fashion, beginning with non-coercive de-escalation strategies and moving on to pharmacologic interventions and physical restraints as necessary. Face-to-face examination, monitoring, and documentation by the physician are essential. The emergency physician should be familiar with multiple pharmaceutical options, tailored to the individual patient. Use of ketamine, benzodiazepines and antipsychotics should be considered. Patient autonomy, safety, and medical well-being are paramount.

Comparison of Droperidol and Midazolam Versus Haloperidol and Lorazepam for Acute Agitation Management in the Emergency Department

BACKGROUND

Acute agitation accounts for up to 2.6% of visits to the emergency department (ED). To date, a standard of care for the management of acute agitation has not been established. Few studies have evaluated antipsychotic and benzodiazepine combinations.

OBJECTIVE

The purpose of this study was to evaluate effectiveness and safety of combination therapy for acute agitation with intramuscular (IM) droperidol and midazolam (D+M) compared with IM haloperidol and lorazepam (H+L) in patients in the ED.

METHODS

This was a single-center, retrospective medical record review of patients presenting to a large, academic ED with acute agitation from July 2020 through October 2021. The primary outcome was percentage of patients requiring additional agitation medication within 60 minutes of combination administration. Secondary outcomes included average time to repeat dose administration and average number of repeat doses required before ED discharge.

RESULTS

A total of 306 patients were included for analysis: 102 in the D+M group and 204 in the H+L group. Repeat dose within 60 minutes occurred in 7 (6.9%) and 28 (13.8%) patients in the D+M and H+L groups, respectively (P = 0.065). A total of 28.4% of D+M patients and 30.9% of H+L patients required any repeat dose during their ED visit. Time to repeat dose was 12 and 24 minutes in the D+M and H+L, respectively (P = 0.22). The adverse event rate was 2.9% in each group.

CONCLUSION AND RELEVANCE

IM D+M resulted in a lower rate of repeat doses of acute agitation medication compared with IM H+L, though this was not statistically significant. Both therapies were safe, and the adverse event rate was low.

Ketamine: A Practical Review for the Consultation-Liaison Psychiatrist

BACKGROUND

Ketamine is a noncompetitive N-methyl-D-aspartate-receptor antagonist often used for sedation and management of acute agitation in general hospital settings. Many hospitals now include ketamine as part of their standard agitation protocol, and consultation-liaison psychiatrists frequently find themselves treating patients who have received ketamine, despite lack of clear recommendations for management.

OBJECTIVE

Conduct a nonsystematic narrative review regarding the use of ketamine for agitation and continuous sedation, including benefits and adverse psychiatric effects. Compare ketamine to more traditional agents of agitation control. Provide consultation-liaison psychiatrists with a summary of available knowledge and recommendations for managing patients receiving ketamine.

METHODS

A literature review was performed using PubMed, querying published articles from inception to March 2023 for articles related to use of ketamine for agitation or continuous sedation and side effects including psychosis and catatonia.

RESULTS

A total of 37 articles were included. Ketamine was found to have multiple benefits, including shorter time to adequate sedation for agitated patients when compared to haloperidol ± benzodiazepines and unique advantages for continuous sedation. However, ketamine carries significant medical risks including high rates of intubation. Ketamine appears to induce a syndrome that mimics schizophrenia in healthy controls, and such effects are more pronounced and longer-lasting in patients with schizophrenia. Evidence regarding rates of delirium with ketamine for continuous sedation is mixed and requires further investigation before the agent is widely adopted for this purpose. Finally, the diagnosis of "excited delirium syndrome" and use of ketamine to treat this controversial syndrome warrants critical evaluation.

CONCLUSIONS

Ketamine carries many potential benefits and can be an appropriate medication for patients with profound undifferentiated agitation. However, intubation rates remain high, and ketamine may worsen underlying psychotic disorders. It is essential that consultation-liaison psychiatrists understand the advantages, disadvantages, biased administration, and areas of limited knowledge regarding ketamine.

Is Ketamine an Effective Treatment of Acute Agitation in the Emergency Department? Implications for APRN Practice

This article reviews the results of a randomized controlled trial, "Rapid Agitation Control with Ketamine in the Emergency Department: A Blinded, Randomized Controlled Trial" by D. Barbic et al. (2021), comparing time to sedation, level of sedation, and adverse outcomes between intramuscular ketamine versus intramuscular midazolam and haloperidol among acutely agitated patients presenting to the emergency department (ED). The findings are discussed in the context of practice change for patient stabilization within the ED. Emergency department nurse practitioners must employ continuing education and remain current with clinical practices and treatment options to ensure that patients receive optimal safe care. Although the use of midazolam and haloperidol has historically been the first-line treatment for the acutely agitated patient, use of ketamine shows promise in providing a safe alternative for expedited patient stabilization for acutely agitated patients presenting to the ED.

Refractory Hyperactive Delirium Without Intravenous Access: A Case Report

Refractory delirium is a complex, often underdiagnosed, and difficult-to-treat phenomenon. It poses significant challenges to healthcare providers, especially in patients without prior intravenous access. In extreme cases, anesthetic management may be needed to treat refractory delirium. Here, we present a unique case of postoperative hyperactive refractory delirium in a patient without intravenous access, ultimately requiring anesthetic management for resolution.

Prescribing Practices for Agitation Medication in Obese Patients Admitted to the Emergency Department

INTRODUCTION

Weight is a factor that influences the dosages of many medications, although no clinical studies have evaluated this factor in the use of agitation medications in the obese population. The objectives of this study were to assess the need for weight considerations in dosing antipsychotics and benzodiazepines for patients with agitation and to assess prescribing patterns in agitated patients.

METHODS

This retrospective cohort study compared outcomes between obese and nonobese adult patients who received at least one parenteral administration of an antipsychotic or benzodiazepine for agitation in the emergency department. The primary outcomes were total antipsychotic and benzodiazepine doses within 24 hours (in chlorpromazine equivalents and lorazepam equivalents, respectively). Key secondary outcomes included antipsychotic and benzodiazepine doses used for first administration, incidence of repeat emergency medication administration within 24 hours, time to next administration, and number of repeat administrations within 24 hours.

RESULTS

The study examined 115 patient encounters in each cohort of patients in the study. The baseline characteristics of the 2 study cohorts were similar. Both groups had similar mean 24-hour antipsychotic usage [272.7 chlorpromazine equivalents (nonobese cohort), 313.5 chlorpromazine equivalents (obese cohort); P=0.157] and mean 24-hour benzodiazepine usage [0.9 lorazepam equivalents (both cohorts); P=0.750]. Differences between the study cohorts on all of the secondary outcomes were also not statistically significant (P>0.05).

DISCUSSION

This study did not find the use of higher dosages of agitation medication in the obese compared with the nonobese population. Future prospective trials, with possible emphasis on individual medications, specific etiologies of agitation, or morbid obesity, are required to confirm this finding or to elucidate potential differences in optimal medication dosages for the obese population.

Retrospective evaluation of ketamine versus droperidol on time to restraint removal in agitated emergency department patients

PURPOSE

Acute agitation and violent behavior in the emergency department (ED) can lead to significant patient morbidity and contribute to the growing problem of workplace violence against health care providers. To our knowledge, there is no available literature directly comparing intramuscular ketamine to intramuscular droperidol in ED patients presenting with undifferentiated agitation. The purpose of this investigation was to compare the effectiveness and safety of these agents for acute agitation in the ED.

METHODS

This was a retrospective observational study conducted at an urban, academic ED. The primary endpoint was time from the first dose of study medication to restraint removal. Safety endpoints included incidence of bradycardia (heart rate < 60 bpm), hypotension (systolic blood pressure < 90 mmHg), hypoxia (oxygen saturation < 90% or need for respiratory support), and incidence of intubation for ongoing agitation or respiratory failure.

RESULTS

An initial 189 patients were screened, of which, 92 met inclusion criteria. The median time from initial drug administration to restraint removal was 49 min (IQR 30, 168) in the ketamine group and 43 min (IQR 30, 80) in the droperidol group (Median difference 6 min; 95% CI [-7, 26]). There was no significant difference in rates of bradycardia (3% vs 3%, 95% CI [-7%, 8%]), hypotension (0% vs 2%, 95% CI [-5%, 2%]), or hypoxia (7% vs 10%, 95% CI [-15%, 9%]) in the ketamine versus droperidol groups respectively. One patient in the ketamine group was intubated for ongoing agitation, and one patient in the droperidol group was intubated for respiratory failure.

CONCLUSIONS

Intramuscular droperidol and intramuscular ketamine were associated with similar times from drug administration to restraint removal in patients presenting to the ED with undifferentiated agitation. Prospective studies are warranted to evaluate IM droperidol and IM ketamine head-to-head as first line agents for acute agitation in the ED.

Prehospital Use of Ketamine versus Benzodiazepines for Sedation among Pediatric Patients with Behavioral Emergencies

INTRODUCTION

Ketamine is an emerging alternative sedation agent for prehospital management of agitation, yet research is limited regarding its use for children. Our objective was to compare the effectiveness and safety of ketamine and benzodiazepines when used for emergent prehospital sedation of pediatric patients with behavioral emergencies.

METHODS

We performed a retrospective review of 9-1-1 EMS records from the 2019-2020 ESO Data Collaborative research datasets. We included patients ≤18 years of age who received ketamine or benzodiazepines for EMS primary and secondary impressions indicating behavioral conditions. We excluded patients with first Glasgow Coma Scale (GCS) scores ≤8, those receiving ketamine or benzodiazepines prior to EMS arrival, those receiving both ketamine and benzodiazepines, and interfacility transfers. Effectiveness outcomes included general clinician assessment of improvement, decrease in GCS, and administration of a subsequent sedative. Safety outcomes included mortality; advanced airway placement; ventilatory assistance without advanced airway placement; or marked sedation (GCS ≤8). Chi-square and t-tests were used to compare the ketamine and benzodiazepines groups.

RESULTS

Of 57,970 pediatric patients with behavioral complaints and GCS scores >8, 1,539 received ketamine (13.3%, n = 205) or a benzodiazepine (86.7%, n = 1,334). Most patients were ≥12 years old (89.2%, n = 1,372), predominantly Caucasian (48.3%, n = 744), and were equally distributed by sex (49.7% male, n = 765). First treatment with ketamine was associated with a greater likelihood of improvement (88.8% vs 70.5%, p < 0.001) and a greater average GCS reduction compared to treatment with benzodiazepines (-2.5 [SD:4.0] vs -0.3 [SD:1.7], p < 0.001). Fewer patients who received ketamine received subsequent medication compared to those who received benzodiazepines (12.2% vs 27.0%, p < 0.001). Marked sedation was more frequent with ketamine than benzodiazepines (28.8% vs 2.9%, p < 0.001). Provision of ventilatory support (1.5% vs 0.5%, p = 0.14) and advanced airway placement (1.0% vs 0.2%, p = 0.09) were similar between ketamine and benzodiazepine groups. No prehospital deaths were reported.

CONCLUSION

In this pediatric cohort, prehospital sedation with ketamine was associated with greater patient improvement, less subsequent sedative administration, and greater sedation compared to benzodiazepines. Though we identified low rates of adverse events in both groups, ketamine was associated with more instances of marked sedation, which bears further study.

The Perioperative Anesthetic Management of the Pediatric Patient with Special Needs: An Overview of Literature

The perioperative management of pediatric patients with psycho-physical disorders with related relational and cognitive problems must be carefully planned, in order to make the entire hospitalization process as comfortable and as less traumatic as possible. This article reports an overview of the anesthetic management of non-cooperative patients between 6 and 14 years old. The pathologies most frequently responsible for psycho-physical disorders can be summarized into three groups: (1) collaboration difficulties (autism spectrum disorders, intellectual impairment, phobia); (2) motor dysfunction (cerebral palsy, epilepsy, other brain pathologies, neuromuscular disorders), and (3) craniofacial anomalies (Down syndrome, other genetic syndromes). Anesthesia can be performed safely and successfully due to careful management of all specific problems of these patients, such as a difficult preoperative evaluation (medical history, physical examination, blood sampling, evaluation of vital parameters and predictive indices of difficult airway) and the inapplicability of a "standard" perioperative path (timing and length of the hospitalization, anesthetic premedication, postoperative management). It is necessary to ensure a dedicated perioperative process that is safe, comfortable, tailored to specific needs, and as less traumatic as possible. At the same time, all necessary precautions must be taken to minimize possible complications.

Intubation Rates following Prehospital Administration of Ketamine for Acute Agitation: A Systematic Review and Meta-Analysis

BACKGROUND

Ketamine is a fast-acting, dissociative anesthetic with a favorable adverse effect profile that is effective for managing acute agitation as a chemical restraint in the prehospital and emergency department (ED) settings. However, some previously published individual studies have reported high intubation rates when ketamine was administered prehospitally.

OBJECTIVE

This systematic review aims to determine the rate and settings in which intubation following prehospital administration of ketamine for agitation is occurring, as well as associated indications and adverse events.

METHODS

We searched PubMed, Scopus, Ovid MEDLINE, Embase, CINAHL Plus, PsycINFO, the Cochrane Library, ClinicalTrials.gov, OpenGrey, Open Access Theses and Dissertation, and Google Scholar from the earliest possible date until 13/February/2022. Inclusion criteria required studies to describe agitated patients who received ketamine in the prehospital setting as a first-line drug to control acute agitation. Reference lists of appraised studies were screened for additional relevant articles. Study quality was assessed using the Newcastle-Ottawa quality assessment scale. Synthesis of results was completed via meta-analysis, and the GRADE tool was used for certainty assessment.

RESULTS

The search yielded 1466 unique records and abstracts, of which 50 full texts were reviewed, resulting in 18 being included in the analysis. All studies were observational in nature and 15 were from USA. There were 3476 patients in total, and the overall rate of intubation was 16% (95% confidence interval [CI] = 8%-26%). Most intubations occurred in the ED. Within the studies, the prehospital intubation rate ranged from 0% to 7.9% and the ED intubation rate ranged from 0 to 60%. The overall pooled prehospital intubation rate was 1% (95% CI = 0%-2%). The overall pooled ED intubation rate was 19% (95% CI = 11%-30%). The most common indications for intubation were for airway protection and respiratory depression/failure.

CONCLUSIONS

There is wide variation in intubation rates between and within studies. The majority of intubations performed following prehospital administration of ketamine for agitation took place in the ED.

Novel uses of ketamine in the emergency department

INTRODUCTION

: Ketamine is gaining renewed interest among healthcare providers due to its novel clinical applications in the emergency department (ED) setting.

AREAS COVERED

: This article provides a comprehensive discussion of ketamine's pharmacological properties, including safety profile and adverse effects, in addition to an overview of current evidence for ketamine (racemic formulation) in the management of ED patients with acute agitation, pain, and depression/suicide ideation.

EXPERT OPINION

: Ketamine is an effective adjunct to opioids, providing greater pain relief than morphine alone. As an analgesic agent, administration of ketamine (0.1-0.3 mg/kg IV) alone can provide analgesia similar to that of morphine in patients with acute visceral and musculoskeletal pain. Moreover, ketamine provides equal analgesic efficacy to morphine in a variety of chronic painful conditions including pain associated with cancer, vaso-occlusive pain crisis associated with sickle cell disease, and in patients with high opioid tolerance and/or opioid dependency. Available literature shows that ketamine (1-2mg/kg IV or 4-5 mg/kg IM) is a safe, rapid (<5 minutes) and effective tranquilization agent for ED patients with acute agitation. Finally, there is growing evidence that suggests ketamine may have a potential utility in the management of patients with self-harm ideation or acute depressive episodes. Intravenous infusion of ketamine (0.5 mg/kg over 40 mins) has been shown to produce an antidepressant effect and decrease in suicidal ideation within 4 hours with effects lasting up to one week.

Promises and Pitfalls of NMDA Receptor Antagonists in Treating Violent Aggression

Treatment options for chronically aggressive individuals remain limited despite recent medical advances. Traditional pharmacological agents used to treat aggression, such as atypical antipsychotics, have limited efficacy and are often replete with dangerous side effects. The non-competitive NMDAR antagonists ketamine and memantine are promising alternatives, but their effects appear to be highly dependent on dosage, context, and personal experience. Importantly, these drugs can increase aggression when combined with substances of abuse or during periods of heightened stress. This is likely due to mechanistic differences operating at specific synapses under different contexts. Previous findings from our lab and others have shown that early life stress, substance abuse, and attack experience promote aggression through NMDAR-dependent synaptic plasticity within aggression-related brain circuits. Ketamine and memantine affect these types of aggression in opposite ways. This has led us to propose that ketamine and memantine oppositely affect aggression brought on by early life stress, substance abuse, or attack experience through opposite effects on NMDAR-dependent synaptic plasticity. This would account for the persistent effects of these drugs on aggression and suggest they could be leveraged as a more long-lasting treatment option. However, a more thorough examination of the effects of ketamine and memantine on cellular and synaptic function will be necessary for responsible administration. Additionally, because the effects of ketamine and memantine are highly dependent on prior drug use, traumatic stress, or a history of aggressive behavior, we propose a more thorough medical evaluation and psychiatric assessment will be necessary to avoid possible adverse interactions with these drugs.

A Comparative Analysis Between Ketamine Versus Combination of Midazolam and Haloperidol for Rapid Safe Control of Agitated Patients in Emergency Department: A Systematic Review

We aim to discuss the efficacy and adverse effects of using ketamine in agitated patients in the emergency department (ED) compared with the combination therapy of haloperidol with benzodiazepine.

This systematic review followed Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines. An electronic search from PubMed/Medline, Cochrane library, and Google Scholar was conducted from their inception to 30^th April 2022. We included agitated patients in ED who were given infusion with ketamine only. Our comparative group was patients infused with combined therapy of haloperidol and benzodiazepine. We did not include letters, case reports, abstracts, conference papers, appraisals, reviews, and studies where full text was unavailable. We did not put any language restrictions.

Three studies were selected in our manuscript (one cohort and two randomized controlled trials). All three studies showed that ketamine was used to achieve sedation in less time than the other group. However, two studies reported significantly more adverse effects in ketamine-infused groups.

We concluded that ketamine use is superior when its primary focus is to sedate the patient as quickly as possible, but it carries some side effects that should be considered. However, we still need more studies assessing the efficacy of ketamine in agitated patients presenting in the ED.

Rapid tranquilization of the agitated patient in the emergency department: A systematic review and network meta-analysis

BACKGROUND

Safe and effective tranquilization of the acutely agitated patient is challenging, and head-to-head comparisons of medications are limited. We aimed to identify the most optimal agent(s) for rapid tranquilization of the severely agitated patient in the emergency department (ED).

METHODS

The protocol for systematic review was registered (PROSPERO; CRD42020212534). We searched MEDLINE, Embase, PsycINFO, and Cochrane Database/CENTRAL from inception to June 2, 2021. We limited studies to randomized controlled trials that enrolled adult ED patients with severe agitation and compared drugs for rapid tranquilization. Predetermined outcomes were: 1) Adequate sedation within 30 min (effectiveness), 2) Immediate, serious adverse event - cardiac arrest, ventricular tachydysrhythmia, endotracheal intubation, laryngospasm, hypoxemia, hypotension (safety), and 3) Time to adequate sedation (effect onset). We extracted data according to PRISMA-NMA and appraised trials using Cochrane RoB 2 tool. We performed Bayesian network meta-analysis (NMA) using a Markov Chain Monte Carlo method with random-effects model and vague prior distribution to calculate odds ratios with 95% credible intervals for dichotomous outcomes and frequentist NMA to calculate mean differences with 95% confidence intervals for continuous outcomes. We assessed confidence in results using CINeMA. We used surface under the cumulative ranking (SUCRA) curves to rank agent(s) for each outcome.

RESULTS

Eleven studies provided data for effectiveness (1142 patients) and safety (1147 patients). Data was insufficient for effect onset. The NMA found that ketamine (SUCRA = 93.0%) is most likely to have superior effectiveness; droperidol-midazolam (SUCRA = 78.8%) is most likely to be safest. There are concerns with study quality and imprecision. Quality of the point estimates varied for effectiveness but mostly rated "very low" for safety.

CONCLUSIONS

Available evidence suggests that ketamine and droperidol have intermediate effectiveness for rapid tranquilization of the severely agitated patient in the ED. There is insufficient evidence to definitively determine which agent(s) may be safest or fastest-acting. Further, direct-comparison study of ketamine and droperidol is recommended.