The analgesic effect of combined treatment with intranasal S-ketamine and intranasal midazolam compared with morphine patient-controlled analgesia in spinal surgery patients: a pilot study

The efficacy of nasal administration of esketamine in patients having moderate-to-severe pain after preoperative CT-guided needle localization: a randomized, double-blind, placebo-controlled trial

Background

Whether nasal administration of esketamine can provide effective analgesia is unclear in patients with acute pain after preoperative CT-guided needle localization.

Methods

In this double-blind, randomized, placebo-controlled trial, patients were assigned to receive either nasal administration of esketamine (0.3 mg/kg or 0.5 mg/kg) or saline (identical in appearance to esketamine) when they had visual analog scale (VAS) pain scores >3/10 during deep breathing after preoperative CT-guided needle localization. The primary outcome was the percentage of patients with satisfactory pain relief, which was defined as VAS pain scores ≤3/10 measured 15 min after intranasal of esketamine or saline. Secondary outcomes included VAS measured following esketamine or saline, the incidence and cumulative dose of rescue hydromorphone use, and related adverse events.

Results

A total of 90 patients were included in the final analysis. Following intranasal treatment, the percentage of patients with satisfactory pain relief was 16.7% (5/30) in the saline group, 56.7% (17/30) in the 0.3 mg/kg esketamine group, and 53.3% (16/30) in the 0.5 mg/kg esketamine group (p = 0.002). The median VAS during deep breathing was less after the intranasal administration of esketamine {median (IQR), 3 (3, 5) in 0.3 mg/kg or 0.5 mg/kg esketamine compared to the saline group [5 (4, 6)], p = 0.009}. The incidence of rescue hydromorphone use was detected less in the esketamine group compared to the saline group (43.3% in the 0.3 mg/kg esketamine group, 36.7% in the 0.5 mg/kg esketamine group, and 73.3% in the saline group, p = 0.010). The adverse events were similar among the three groups (p > 0.05).

Conclusion

Intranasal administration of esketamine is easier and more effective in alleviating acute pain in patients after preoperative CT-guided needle localization without significant adverse effects.

Effect of Intranasal Ketamine on Pain Intensity after Cesarean Section: A Single-Center, Double Blind, Randomized Controlled Trial

Background

Although intravenous or intramuscular opioids are widely used for managing postoperative pain after cesarean section (CS), their side effects are bothering and limit their use. The aim of this study was to determine the effect of intranasal ketamine on pain intensity after CS.

Methods

In a single-center, double-blind, parallel-group, randomized controlled trial, a total of 120 patients who were scheduled for elective CS were randomly assigned into two groups. After birth, 1 mg of midazolam was administered to all patients. In addition, 1 mg/kg intranasal ketamine was administered to patients in the intervention group. For patients in control group, normal saline was administered intranasally as a placebo. The severity of pain and nausea in the two groups was evaluated after 15, 30 and 60 minutes, as well as 2, 6 and 12 hours after the initial administration of the medications.

Results

The trend of changes in pain intensity was decreasing and these changes were statistically significant (time effect; P<0.001). The pain intensity in the placebo group was higher than the intervention and the observed difference was statistically significant, regardless of the time studied (group effect; P<0.001). In addition, it was shown that regardless of the study group, the trend of changes in nausea severity was decreasing and these changes were statistically significant (time effect; P<0.001). Regardless of the time studied, the severity of nausea in the placebo group was higher than the intervention group (group effect; P<0.001).

Conclusions

According to the results of this study, it seems that the using of intranasal ketamine (1 mg/kg), can be considered as an effective, well tolerated and safe method in reducing pain intensity as well as the need for postoperative opioid consumption after CS.

[Analgesia for trauma patients in emergency medicine]

Adequate analgesia is one of the most important measures of emergency care in addition to treatment of vital function disorders and, if indicated, should be promptly undertaken; however, a large proportion of emergency patients receive no or only inadequate pain therapy. The numeric rating scale (NRS) is recommended for pain assessment but is not applicable to every group of patients; therefore, vital signs and body language should be included in the assessment. Pain therapy should reduce the NPRS to <5 points. Ketamine and fentanyl, which have an especially rapid onset of action, and also morphine are suitable for analgesia in spontaneously breathing patients. Basic prerequisites for safe and effective analgesia by healthcare professionals are the use of adequate monitoring, the provision of well-defined emergency equipment, and the mastery of emergency procedures. In a structured competence system, paramedics and nursing personnel can perform safe and effective analgesia.

IMPORTANCE trial: a provisional study-design of a single-center, phase II, double-blinded, placebo-controlled, randomized, 4-week study to compare the efficacy and safety of intranasal esketamine in chronic opioid refractory pain

Background:  Cancer is the second leading cause of death globally. Up to 86% of advanced cancer patients experience significant pain, while 10-20% live in chronic pain. Besides, increasing prescription of opioids resulted in 33,000 deaths in the US in 2015. Both reduce patients’ functional status and quality of life. While cancer survival rates are increasing, therapeutic options for chronic opioid refractory pain are still limited. Esketamine is the s-enantiomer of ketamine, with superior analgesic effect and less psychotomimetic side effects. Intranasal esketamine was approved by the FDA for treatment-resistant depression. However, its use in chronic cancer pain has never been tested. Therefore, we propose a phase II, randomized, placebo-controlled trial to evaluate the efficacy and safety of intranasal esketamine in chronic opioid refractory cancer pain.

Methods and analysis: We will recruit 120 subjects with chronic opioid refractory pain, defined as pain lasting more than 3 months despite optimal therapy with high dose opioids (>60 mg morphine equivalent dose/day) and optimal adjuvant therapy. Subjects will be randomized into two groups: intranasal esketamine (56mg) and placebo. Treatment will be administered twice a week for four consecutive weeks. The primary outcome is defined as reduction in the Numeric Pain Rating Scale (NPRS) after first application. Secondary outcomes include NPRS reduction after four weeks, the number of daily morphine rescue doses, functional status and satisfaction, and depression.

Conclusion: This study may extend therapeutic options in patients with chronic pain, thus improving their quality of life and reducing opioid use.

Trial registration: Clinical Trials.gov, NCT04666623. Registered on 14 December 2020

Zolpidem reduces pain intensity postoperatively: a systematic review and meta-analysis of the effect of hypnotic medicines on post-operative pain intensity

BACKGROUND

This systematic review aimed to investigate whether the administration of hypnotic medicines, z-drugs, melatonin or benzodiazepines, reduced pain intensity postoperatively.

METHODS

Medline, Embase, Cinahl, Psych info, Central and PubMed databases were searched, from inception to February 2020 to identify relevant trials. The search was extended, post hoc, to include meta-Register of Controlled Trials, the Web of Science and the conference booklets for the 14th, 15th, and 16th International Association for the Study of Pain conferences. Two independent reviewers screened titles and abstracts and cross-checked the extracted data.

RESULTS

The search retrieved 5546 articles. After full-text screening, 15 trials were included, which had randomised 1252 participants. There is moderate-quality evidence that in the short-term [WMD - 1.06, CI - 1.48 to - 0.64, p ≤ .01] and low-quality evidence that in the medium-term [WMD - 0.90, CI - 1.43 to - 0.37, p ≤ .01] postoperative period oral zolpidem 5/10 mg with other analgesic medicines reduced pain intensity compared to the same analgesic medicines alone. There is low-quality evidence that melatonin was not effective on postoperative pain intensity compared to placebo. The results of benzodiazepines on pain intensity were mixed. The authors reported no significant adverse events.

CONCLUSIONS

There is promising evidence that the hypnotic medicine zolpidem, adjuvant to other analgesics, is effective at achieving a minimally clinically important difference in pain intensity postoperatively. There is no consistent effect of melatonin or benzodiazepines on postoperative pain intensity. Readers should interpret these results with some caution due to the lack of data on safety, the small number of trials included in the pooled effects and their sample sizes.

SYSTEMATIC REVIEW REGISTRATION

The protocol for this systematic review was registered with PROSPERO ID= CRD42015025327 .

Pharmacokinetics, absolute bioavailability and tolerability of ketamine after intranasal administration to dexmedetomidine sedated dogs

Intranasal ketamine has recently gained interest in human medicine, not only for its sedative, anaesthetic or analgesic properties, but also in the management of treatment resistant depression, where it has been shown to be an effective, fast acting alternative treatment. Since several similarities are reported between human psychiatric disorders and canine anxiety disorders, intranasal ketamine could serve as an alternative treatment for anxiety disordered dogs. However, to the authors knowledge, intranasal administration of ketamine and its pharmacokinetics have never been described in dogs. Therefore, this study aimed to examine the pharmacokinetics, absolute bioavailability and tolerability of intranasal ketamine administration compared with intravenous administration. Seven healthy, adult laboratory Beagle dogs were included in this randomized crossover study. The dogs received 2 mg/kg body weight ketamine intravenously (IV) or intranasally (IN), with a two-week wash-out period. Prior to ketamine administration, dogs were sedated intramuscularly with dexmedetomidine. Venous blood samples were collected at fixed times until 480 min post-administration and ketamine plasma concentrations were determined by liquid chromatography-tandem mass spectrometry. Cardiovascular parameters and sedation scores were recorded at the same time points. Non-compartmental pharmacokinetic analysis revealed a rapid (Tmax = 0.25 ± 0.14 h) and complete IN bioavailability (F = 147.65 ± 49.97%). Elimination half-life was similar between both administration routes (T1/2el IV = 1.47 ± 0.24 h, T1/2el IN = 1.50 ± 0.97 h). Heart rate and sedation scores were significantly higher at 5 and 10 min following IV administration compared to IN administration, but not at the later time-points.

Acute Pain Management in Emergency Department, Low Dose Ketamine Versus Morphine, A Randomized Clinical Trial

Background

Ketamine, as an opium alternative, has been proposed for pain relief in the emergency department (ED).

Objectives

This study was carried out to compare low dose ketamine (LDK) with morphine for pain relief in trauma patients.

Methods

In this randomized double-blinded clinical trial, 300 trauma patients from the ED of 2 teaching hospitals in Tehran, Iran were enrolled and randomly divided into 2 equal groups. The 1st group received 0.2 mg/kg of ketamine while the 2nd group received 0.1 mg/kg of intravenous morphine. The pain intensity and complications were measured and compared every 15 minutes to 1 hour.

Results

Fifteen minutes after drug injection in both groups, a significant reduction was found in average pain intensity compared to the initial pain (P = 0.01). At 15 minutes, no significant difference was found in both groups in regards to average pain intensity (P = 0.23). The average pain intensity at 30, 45, and 60 minutes in the group receiving morphine was lower than the ketamine group (P = 0.01, P < 0.001, P < 0.001 respectively). Two complications (drop in O₂ saturation below 90% and flushing) were significantly greater in the morphine group.

Conclusions

The results of this study suggest that LDK, at a dose of 0.2 mg/kg, in the earlier minutes leads to significant reduction of pain when compared to that of intravenous morphine. It also created fewer complications than morphine.

Böttiger B, Bouillon B, Fischer M, Gaier G, Gliwitzky B, Helm M, Hilbert-Carius P, Hossfeld B, Meisner C, Schempf B, Wafaisade A, Bernhard M. Analgesia in Patients with Trauma in Emergency Medicine

BACKGROUND

Suitable analgesic drugs and techniques are needed for the acute care of the approximately 18 200-18 400 seriously injured patients in Germany each year.

METHODS

This systematic review and meta-analysis of analgesia in trauma patients was carried out on the basis of randomized, controlled trials and observational studies. A systematic search of the literature over the 10-year period ending in February 2016 was carried out in the PubMed, Google Scholar, and Springer Link Library databases. Some of the considered trials and studies were included in a meta-analysis. Mean differences (MD) of pain reduction or pain outcome as measured on the Numeric Rating Scale were taken as a summarizing measure of treatment efficacy.

RESULTS

Out of 685 studies, 41 studies were considered and 10 studies were included in the meta-analysis. Among the drugs and drug combinations studied, none was clearly superior to another with respect to pain relief. Neither fentanyl versus morphine (MD -0.10 with a 95% confidence interval of [-0.58; 0.39], p = 0.70) nor ketamine versus morphine (MD -1.27 [-3.71; 1.16], p = 0.31), or the combination of ketamine and morphine versus morphine alone (MD -1.23 [-2.29; -0.18], p = 0.02) showed clear superiority regarding analgesia.

CONCLUSION

Ketamine, fentanyl, and morphine are suitable for analgesia in spontaneously breathing trauma patients. Fentanyl and ketamine have a rapid onset of action and a strong analgesic effect. Our quantitative meta-analysis revealed no evidence for the superiority of any of the three substances over the others. Suitable monitoring equipment, and expertise in emergency procedures are prerequisites for safe and effective analgesia by healthcare professionals..