Efficacy of analgesic and sub-dissociative dose ketamine for acute pain in the emergency department

The 90% effective dose of ciprofol and propofol with S-ketamine for painless abortion: a randomized, double-blind, sequential dose-finding trial

Background

Unlike the propofol-opioids combination, a single dose of S-ketamine with propofol achieves the same anesthetic effects while effectively minimizing adverse reactions in painless abortion. Ciprofol, a novel analog of propofol, has distinct advantages, its application in painless abortion is underexplored.

Objectives

To investigate a 90% effective dose (ED90) of ciprofol and propofol with S-ketamine for painless abortion.

Design

This prospective biased coin up-and-down (BCUD) sequential dose-finding study aimed to estimate the ED90 of ciprofol when administered with 0.15 mg/kg S-ketamine in painless abortion while comparing adverse effects incidence with the ED90 of propofol when combined with the same dose of S-ketamine.

Methods

Eighty patients were recruited and randomly allocated to either ciprofol or propofol groups, with initial doses of 0.375 mg/kg and 1.5 mg/kg, respectively. The dose for the subsequent patient in the study was based on the response of the preceding patient, following the BCUD design. The study estimated the ED90 using isotonic regression. Secondary outcomes, including the incidence of injection pain, vital signs, and adverse events, were recorded and compared between the two groups.

Results

The ED90 of ciprofol with 0.15 mg/kg S-ketamine was 0.498 mg/kg (95% confidence interval: 0.498-0.510), while the ED90 of propofol with 0.15 mg/kg S-ketamine was 1.99 mg/kg (95% confidence interval: 1.98-2.16). Patients in the ciprofol group had a lower incidence of respiratory pause (7.5% vs 52.5%; p < 0.001). Other adverse events and recovery time were comparable between groups.

Conclusion

Compared to propofol and S-ketamine combination, ciprofol and S-ketamine are equally effective with reduced respiratory depression. Thus, clinicians should consider a dose of 0.5 mg/kg ciprofol with 0.15 mg/kg S-ketamine for painless abortion.

Trial registration

http://www.chictr.org.cn; ChiCTR2400086522; July 5, 2024.

High- versus low-dose ketamine for analgesia in older adults in the emergency department

BACKGROUND AND OBJECTIVES

Ketamine is increasingly being utilized in the management of acute pain in the emergency department (ED), including for older adults, a population at increased risk of adverse effects from medications. We aimed to compare the safety and analgesic effects of high-dose (≥0.3mg/kg) to low-dose (<0.3mg/kg) intravenous (IV) ketamine among older ED patients.

METHODS

Multi-center, retrospective cohort study of adults ≥60years who received IV ketamine for pain between 2018 and 2021. The primary outcome was pain improvement as measured by the Numerical Rating Scale (NRS) pain score within 60min after administration. Secondary outcomes included adverse effects (early discontinuation, nausea, rescue benzodiazepines and intubation) and the need for rescue analgesia. Linear regression was used to assess the association between the change in NRS pain scores and dose after adjusting for baseline pain, requiring an additional dose of ketamine, and receiving an opioid.

RESULTS

A total of 130 older adults received ketamine as an analgesic (37 high-dose, 93 low-dose). Median age was 69.2years, 52 % were women, 40 % had a history of substance use disorder. Prior to ketamine, 76 % received alternate analgesics and 23 % antiemetics. Baseline mean pain score was lower in the high-dose group (6.7 vs. 8.3, difference -1.7 [95 % CI -2.6 to -0.7], p = 0.013). Change in NRS pain scores were similar between the high-dose and low-dose groups (-2.4 [95 % CI -3.6 to -1.3] vs -1.6 [95 % CI -2.2 to -0.9], p = 0.27). After adjustment for baseline pain score, the high-dose group had a larger reduction in pain scores (-1.3 [95 % CI -2.6 to -0.1], p = 0.042) and percent change of pain (-23.8 % [95 % CI -42.1 % to -5.4 %], p = 0.012). There was no significant difference in rates of rescue analgesia (35.1 % vs. 44.1 %, p = 0.35) or early discontinuation (29.7 % vs. 32.3 %, p = 0.78). Rates of adverse effects were similar.

CONCLUSION

High-dose and low-dose ketamine reduced pain scores in older adults. High-dose ketamine led to a greater reduction in pain scores, and there was no observed difference in adverse effects or the need for rescue analgesia. One-third needed discontinuation of ketamine in both groups.

Smart Response Biomaterials for Pain Management

The intricate nature of pain classification and mechanism constantly affects the recovery of diseases and the well-being of patients. Key medical challenges persist in devising effective pain management strategies. Therefore, a comprehensive review of relevant methods and research advancements in pain management is conducted. This overview covers the main categorization of pain and its developmental mechanism, followed by a review of pertinent research and techniques for managing pain. These techniques include commonly prescribed medications, invasive procedures, and noninvasive physical therapy methods used in rehabilitation medicine. Additionally, for the first time, a systematic summary of the utilization of responsive biomaterials in pain management is provided, encompassing their response to physical stimuli such as ultrasound, magnetic fields, electric fields, light, and temperature, as well as changes in the physiological environment like reactive oxygen species (ROS) and pH. Even though the application of responsive biomaterials in pain management remains limited and at a fundamental level, recent years have seen the examination and debate of relevant research findings. These profound discussions aim to provide trends and directions for future research in pain management.

Comparison of Nebulized Ketamine to Intravenous Subdissociative Dose Ketamine for Treating Acute Painful Conditions in the Emergency Department: A Prospective, Randomized, Double-Blind, Double-Dummy Controlled Trial

STUDY OBJECTIVE

We aimed to assess and compare the analgesic efficacy and adverse effects of intravenous subdissociative-dose ketamine to nebulized ketamine in emergency department (ED) patients with acute painful conditions.

METHODS

We conducted a prospective, randomized, double-blind, double-dummy clinical trial in adult patients (ages 18 and older) with a numerical rating scale pain score of ≥5. We randomized subjects to receive either a single dose of 0.3 mg/kg of intravenous (IV) ketamine or 0.75 mg/kg of nebulized ketamine through a breath-actuated nebulizer. Primary outcome was the difference in pain scores on the numerical rating scale between groups at 30 minutes postmedication administration. The secondary outcomes included the need for rescue analgesia, occurrences of adverse events in each group, and the difference in pain scores at 15, 30, 60, 90, and 120 minutes. We calculated a 95% confidence interval (CI) for a mean difference at 30 minutes, with a minimum clinically important difference set at 1.3 points.

RESULTS

We enrolled 150 subjects (75 per group). Mean pain scores through numerical rating scale were 8.2 for both groups at baseline, which decreased to 3.6 and 3.8 at 30 minutes, yielding a mean difference of 0.23 (95% CI -1.32 to 0.857). We observed no clinically concerning changes in vital signs. No serious adverse events occurred in any of the groups throughout the study period.

CONCLUSION

We found no difference between the administration of IV and nebulized ketamine for the short-term treatment of moderate to severe acute pain in the ED, with both treatments providing a clinically meaningful reduction in pain scores at 30 minutes.

Ketamine Compared With Morphine for Out-of-Hospital Analgesia for Patients With Traumatic Pain: A Randomized Clinical Trial

Importance

Pain is a common out-of-hospital symptom among patients, and opioids are often prescribed. Research suggests that overprescribing for acute traumatic pain is still prevalent, even when limits restricting opioid prescriptions have been implemented. Ketamine hydrochloride is an alternative to opioids in adults with out-of-hospital traumatic pain.

Objective

To assess the noninferiority of intravenous ketamine compared with intravenous morphine sulfate to provide pain relief in adults with out-of-hospital traumatic pain.

Design, Setting, and Participants

The Intravenous Subdissociative-Dose Ketamine Versus Morphine for Prehospital Analgesia (KETAMORPH) study was a multicenter, single-blind, noninferiority randomized clinical trial comparing ketamine hydrochloride (20 mg, followed by 10 mg every 5 minutes) with morphine sulfate (2 or 3 mg every 5 minutes) in adult patients with out-of-hospital trauma and a verbal pain score equal to or greater than 5. Enrollment occurred from November 23, 2017, to November 26, 2022, in 11 French out-of-hospital emergency medical units.

Interventions

Patients were randomly assigned to ketamine (n = 128) or morphine (n = 123).

Main Outcomes and Measures

The primary outcome was the between-group difference in mean change in verbal rating scale pain scores measured from the time before administration of the study drug to 30 minutes later. A noninferiority margin of 1.3 was chosen.

Results

A total of 251 patients were randomized (median age, 51 [IQR, 34-69] years; 111 women [44.9%] and 140 men [55.1%] among the 247 with data available) and were included in the intention-to-treat population. The mean pain score change was -3.7 (95% CI, -4.2 to -3.2) in the ketamine group compared with -3.8 (95% CI, -4.2 to -3.4) in the morphine group. The difference in mean pain score change was 0.1 (95% CI, -0.7 to 0.9) points. There were no clinically meaningful differences for vital signs between the 2 groups. The intravenous morphine group had 19 of 113 (16.8% [95% CI, 10.4%-25.0%]) adverse effects reported (most commonly nausea [12 of 113 (10.6%)]) compared with 49 of 120 (40.8% [95% CI, 32.0%-49.6%]) in the ketamine group (most commonly emergence phenomenon [24 of 120 (20.0%)]). No adverse events required intervention.

Conclusions and Relevance

In the KETAMORPH study of patients with out-of-hospital traumatic pain, the use of intravenous ketamine compared with morphine showed noninferiority for pain reduction. In the ongoing opioid crisis, ketamine administered alone is an alternative to opioids in adults with out-of-hospital traumatic pain.

Trial Registration

ClinicalTrials.gov Identifier: NCT03236805.