The Expanding Role of Ketamine in the Emergency Department

Nebulized medications in the emergency department: A narrative review of nontraditional agents

PURPOSE

This article summarizes emerging nontraditional therapies administered via the nebulization route for use in the emergency department (ED).

SUMMARY

Although traditional routes of medication administration (eg, intravenous) have been the mainstay of administration modalities for decades, these routes may not be appropriate for all patients. Nowhere is this more readily apparent than in the ED setting, where patients with a variety of presentations receive care. One unique route for medication administration that has increasingly gained popularity in the ED is that of aerosolized drug delivery. This route holds promise as direct delivery of medications to the site of action could yield a more rapid and effective therapeutic response while also minimizing systemic adverse effects by utilizing a fraction of the systemic dose. Medication administration via nebulization also provides an alternative that is conducive to rapid, less invasive access, which is advantageous in the emergent setting of the ED. This review is intended to analyze the existing literature regarding this route of administration, including the nuances that can impact drug efficacy, as well as the available literature regarding novel, noncommercial nebulized medication therapy given in the ED.

CONCLUSION

Multiple medications have been investigated for administration via this route, and when implementing any of these therapies several practical considerations must be taken into account, from medication preparation to administration, to ensure optimal efficacy while minimizing adverse effects. The pharmacist is an essential bedside team member in these scenarios to assist with navigating unique and complex nuances of this therapy as they develop.

Low-dose ketamine versus morphine in the treatment of acute pain in the emergency department: A meta-analysis of 15 randomized controlled trials

OBJECTIVE

To compare the effectiveness and safety of ketamine and morphine in adult patients with acute pain in emergency department (ED) by using a meta-analysis method.

METHODS

This study was based on the Cochrane methodology for conducting a meta-analysis. Only randomized controlled trials (RCTs) were eligible for this study, with an experimental group that received low-dose ketamine and a control group that received morphine. The participants were adults who had acute pain in the ED. The primary outcome measures were the numeric rating scale (NRS) and visual analog scale (VAS). The secondary outcome measures were the complete resolution of pain, NRS reduction ≥3 points, NRS reduction ≥50% or 60%, change of NRS score, change of VAS score, rescue analgesia, satisfaction and adverse events. Subgroup analysis was performed for studies with intravenous and intranasal administration of ketamine. The Review Manager Database was used to analyze the included studies.

RESULTS

15 RCTs involving 1768 patients were included. The ketamine group had lower NRS scores than morphine group at 30 min (MD, -0.77 [95% CI, -0.93 to -0.61]; p < 0.00001), while the morphine had better analgesic effects at 120 min after treatment (MD, 0.33 [95% CI, 0.15 to 051]; p = 0.0003). The subjects of complete resolution of pain in the ketamine group performed better than those in the morphine group at 15 min (RR 3.18, 95% CI 1.75 to 5.78; p = 0.0001). Compared with the morphine group, the ketamine group had a lower incidence of adverse events requiring intervention (RR, 0.34 [95% CI, 0.18 to 0.66]; p = 0.001). Subgroup analysis of intravenous ketamine showed that ketamine had lower VAS score than the morphine group at 30 min. However, also on the 30-min VAS score, intranasal ketamine analgesia was less effective than morphine.

CONCLUSIONS

Ketamine had better analgesic effects in the early stages after treatment, while morphine maintained more durable effects. Compared with morphine, ketamine had a lower incidence of adverse events requiring intervention. The results of subgroup analysis showed that intravenous administration of ketamine was more effective than intranasal administration.

Optimizing the use of ketamine to reduce chronic postsurgical pain in women undergoing mastectomy for oncologic indication: study protocol for the KALPAS multicenter randomized controlled trial

BACKGROUND

Mastectomies are commonly performed and strongly associated with chronic postsurgical pain (CPSP), more specifically termed postmastectomy pain syndrome (PMPS), with 25-60% of patients reporting pain 3 months after surgery. PMPS interferes with function, recovery, and compliance with adjuvant therapy. Importantly, it is associated with chronic opioid use, as a recent study showed that 1 in 10 patients continue to use opioids at least 3 months after curative surgery. The majority of PMPS patients are women, and, over the past 10 years, women have outpaced men in the rate of growth in opioid dependence. Standard perioperative multimodal analgesia is only modestly effective in prevention of CPSP. Thus, interventions to reduce CPSP and PMPS are urgently needed. Ketamine is well known to improve pain and reduce opioid use in the acute postoperative period. Additionally, ketamine has been shown to control mood in studies of anxiety and depression. By targeting acute pain and improving mood in the perioperative period, ketamine may be able to prevent the development of CPSP.

METHODS

Ketamine analgesia for long-lasting pain relief after surgery (KALPAS) is a phase 3, multicenter, randomized, placebo-controlled, double-blind trial to study the effectiveness of ketamine in reducing PMPS. The study compares continuous perioperative ketamine infusion vs single-dose ketamine in the postanesthesia care unit vs placebo for reducing PMPS. Participants are followed for 1 year after surgery. The primary outcome is pain at the surgical site at 3 months after the index surgery as assessed with the Brief Pain Inventory-short form pain severity subscale.

DISCUSSION

This project is part of the NIH Helping to End Addiction Long-term (HEAL) Initiative, a nationwide effort to address the opioid public health crisis. This study can substantially impact perioperative pain management and can contribute significantly to combatting the opioid epidemic.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05037123. Registered on September 8, 2021.

Recent advances in the study of anesthesia-and analgesia-related mechanisms of S-ketamine

Ketamine is a racemic mixture of equal amounts of R-ketamine and S-ketamine and is well known to anesthesiologists for its unique dissociative anesthetic properties. The pharmacological properties of ketamine, namely, its sympathetic excitation, mild respiratory depression, and potent analgesia, are still highly valued in its use as an anesthetic for some patients. In particular, since its advent, S-ketamine has been widely used as an anesthetic in many countries due to its increased affinity for NMDA receptors and its enhanced anesthetic and analgesic effects. However, the anesthetic and analgesic mechanisms of S-ketamine are not fully understood. In addition to antagonizing NMDA receptors, a variety of other receptors or channels may be involved, but there are no relevant mechanistic summaries in the literature. Therefore, the purpose of this paper is to review the mechanisms of action of S-ketamine on relevant receptors and systems in the body that result in its pharmacological properties, such as anesthesia and analgesia, with the aim of providing a reference for its clinical applications and research.

Pharmacotherapy optimization for rapid sequence intubation in the emergency department

PURPOSE

Rapid-sequence intubation (RSI) is the process of administering a sedative and neuromuscular blocking agent (NMBA) in rapid succession to facilitate endotracheal intubation. It is the most common and preferred method for intubation of patients presenting to the emergency department (ED). The selection and use of medications to facilitate RSI is critical for success. The purpose of this review is to describe pharmacotherapies used during the RSI process, discuss current clinical controversies in RSI medication selection, and review pharmacotherapy considerations for alternative intubation methods.

SUMMARY

There are several steps to the intubation process requiring medication considerations, including pretreatment, induction, paralysis, and post-intubation sedation and analgesia. Pretreatment medications include atropine, lidocaine, and fentanyl; but use of these agents in clinical practice has fallen out of favor as there is limited evidence for their use outside of select clinical scenarios. There are several options for induction agents, though etomidate and ketamine are the most used due to their more favorable hemodynamic profiles. Currently there is retrospective evidence that etomidate may produce less hypotension than ketamine in patients presenting with shock or sepsis. Succinylcholine and rocuronium are the preferred neuromuscular blocking agents, and the literature suggests minimal differences between succinylcholine and high dose rocuronium in first-pass success rates. Selection between the two is based on patient specific factors, half-life and adverse effect profiles. Finally, medication-assisted preoxygenation and awake intubation are less common methods for intubation in the ED but require different considerations for medication use.

AREAS FOR FUTURE RESEARCH

The optimal selection, dosing, and administration of RSI medications is complicated, and further research is needed in several areas. Additional prospective studies are needed to determine optimal induction agent selection and dosing in patients presenting with shock or sepsis. Controversy exists over optimal medication administration order (paralytic first vs induction first) and medication dosing in obese patients, but there is insufficient evidence to significantly alter current practices regarding medication dosing and administration. Further research examining awareness with paralysis during RSI is needed before definitive and widespread practice changes to medication use during RSI can be made.

Narrative Review: Low-Dose Ketamine for Pain Management

Pain is the leading cause of medical consultations and occurs in 50-70% of emergency department visits. To date, several drugs have been used to manage pain. The clinical use of ketamine began in the 1960s and it immediately emerged as a manageable and safe drug for sedation and anesthesia. The analgesic properties of this drug were first reported shortly after its use; however, its psychomimetic effects have limited its use in emergency departments. Owing to the misuse and abuse of opioids in some countries worldwide, ketamine has become a versatile tool for sedation and analgesia. In this narrative review, ketamine's role as an analgesic is discussed, with both known and new applications in various contexts (acute, chronic, and neuropathic pain), along with its strengths and weaknesses, especially in terms of psychomimetic, cardiovascular, and hepatic effects. Moreover, new scientific evidence has been reviewed on the use of additional drugs with ketamine, such as magnesium infusion for improving analgesia and clonidine for treating psychomimetic symptoms. Finally, this narrative review was refined by the experience of the Pain Group of the Italian Society of Emergency Medicine (SIMEU) in treating acute and chronic pain with acute manifestations in Italian Emergency Departments.

Single-Dose of Postoperative Ketamine for Postoperative Pain After Mastectomy: A Pilot Randomized Controlled Trial

Background and Objectives

Perioperative ketamine has been shown to reduce opioid consumption and pain after surgery. Ketamine is most often given as an infusion, but an alternative is single-dose ketamine. Single-dose ketamine at up to 1 mg/kg has been shown to reduce symptoms of depression, and a wide range of dosages has been used for pain in the emergency department. However, limited data exists on the tolerability and efficacy of a single-dose of ketamine at 0.6 mg/kg for pain when administered immediately after surgery. We conducted a pilot study of single-dose ketamine in patients undergoing mastectomy with reconstruction, hypothesizing that a single-dose of ketamine is well tolerated and can relieve postoperative pain and improve mood and recovery.

Methods

This is a randomized, single-blind, placebo-controlled, two-arm parallel, single-center study. Thirty adult women undergoing mastectomy with reconstruction for oncologic indication received a single-dose of ketamine (0.6mg/kg) or placebo after surgery in the post-anesthesia care unit (PACU). Patients were followed through postoperative day (POD) 7. The primary outcome was postoperative pain measured by the Brief Pain Inventory (BPI) pain subscale on POD 1 and 2. Secondary outcomes include effects on opioid use, PROMIS fatigue and sleep, mood, Quality of Recovery-15, and the Breast Cancer Pain Questionnaire.

Results

Side effects were minor and not significantly different in frequency between groups. The ketamine group reported lower scores on the BPI pain severity subscale, especially at POD 7; however, the difference was not statistically significant. There were no statistically significant differences between ketamine and placebo groups for the secondary outcomes.

Conclusion

A single-dose of ketamine at 0.6mg/kg administered postoperatively in the PACU is well tolerated in women undergoing mastectomy and may confer better pain control up to one week after surgery. Future studies with larger sample sizes are necessary to adequately characterize the effect of postoperative single-dose ketamine on pain control in this population.

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.

Ketamine: A Potential Adjunct for Severe Benzodiazepine Withdrawal

Following the abrupt cessation of benzodiazepine therapy, patients can present with acute life-threatening withdrawal. Medical management of benzodiazepine withdrawal is typically undertaken with benzodiazepines either through loading dose with gradual taper or symptom triggered treatment, though adjuvant anxiolytics and anticonvulsants are often used. Ketamine, increasingly utilized as an adjunct in the treatment of alcohol withdrawal, may represent an effective medication in the treatment of benzodiazepine withdrawal. In this case report, a 27-year-old male with a history of benzodiazepine and opioid abuse presented to our emergency department with a chief complaint of drug withdrawal. Despite standard treatment with large amounts of benzodiazepine, barbiturate, opioid, and adjunctive medications, the patient remained with severe withdrawal syndrome until an infusion of ketamine (0.5mg/kg in 30 minutes) was administered resulting in significant improvement of the patient symptoms. This case demonstrates the potential role of ketamine as an adjunct medication in the treatment of benzodiazepine withdrawal.

Safety and efficacy of pharmacologic agents used for rapid tranquilization of emergency department patients with acute agitation or excited delirium

Introduction: Management of patients with acute agitation or aggressive behavior can pose a significant challenge to health-care providers in emergency departments. Areas covered: This article provides a comprehensive review of the pharmacologic properties, efficacy, and safety profiles of select intramuscular (IM) sedative agents (i.e., antipsychotics, benzodiazepines, and ketamine) for rapid tranquilization. Expert opinion: Using antipsychotics and benzodiazepines - whether a single agent or combined - will have similar efficacy in producing sedation. But there are differences in the time to sedation depending on which agent is used. Based upon the available studies, droperidol (5-10 mg IM) and midazolam (5-10 mg IM) have the fastest onset of sedation when either is used as a single agent. When combination therapy is used, using midazolam with an antipsychotic agent, instead of lorazepam, may result in faster sedative effect. QT prolongation and torsades de pointes are uncommon adverse drug effects of antipsychotic administration. Ketamine is often reserved as a second-line agent when antipsychotics and benzodiazepines fail to produce the desired tranquilization. However, ketamine (5 mg/kg IM) is more frequently associated with airway compromise requiring endotracheal intubation. A low-dose of ketamine (2 mg/kg IM) may reduce the risk of airway compromise while providing adequate sedation.

Out-of-hospital ketamine: review of a growing trend in patient care

Ketamine is a unique medication with a long history of use in the emergency department. Out-of-hospital indications for ketamine have been explored and are currently expanding in some systems. This article provides background on ketamine history and pharmacology, its use in the hospital environment and possible applications for emergency medical services usage of this medication. Contraindications and adverse reactions are discussed to provide education on the nuances of ketamine administration and mitigation strategies. Out-of-hospital indications for ketamine are discussed including airway management, rapid sequence induction, analgesia, sedation, and treatment of excited delirium.