Pain
December 15, 2004
Nadia Elia, Martin R. Tramèr
564 citations
Ketamine, an NMDA receptor antagonist, reduces postoperative pain and opioid use but carries a risk of hallucinations. In a systematic review of 53 trials (2839 patients), prophylactic intravenous ketamine (median 0.4 mg/kg) lowered pain intensity on a 0–10 scale by 0.89 cm at 6 hours, 0.42 at 12 hours, 0.35 at 24 hours, and 0.27 at 48 hours, and reduced 24-hour morphine consumption by 15.7 mg, without affecting morphine-related adverse effects. Awake or sedated patients receiving ketamine without benzodiazepine had a 2.32 times higher odds of hallucinations (number needed to harm 21). Under general anesthesia, hallucination risk was low regardless of benzodiazepine use. The overall role of ketamine in perioperative analgesia remains unclear.
Pain
August 1, 1999
Roger Schmid, Alan N. Sandler, Joel Katz
547 citations
Ketamine, an anesthetic and short-acting analgesic used for nearly 30 years, has renewed clinical interest as an NMDA receptor antagonist for pain management. This review of randomized, double-blind, controlled trials from 1966 to 1998 examined low-dose ketamine for acute postoperative pain, defined as a bolus less than 2 mg/kg intramuscularly or less than 1 mg/kg intravenously or epidurally, or a continuous intravenous rate of 20 µg/kg per minute or less. The evidence suggests low-dose ketamine may improve postoperative pain management and reduce opioid-related adverse effects when used as an adjunct to local anesthetics, opioids, or other analgesics. Further research is needed on dosing, optimal routes, S(+)-ketamine, long-term outcomes, stability, spinal toxicity, and cognitive effects.
Pain
June 4, 2007
Natalia E. Morone, Carol M. Greco, Debra K. Weiner
544 citations
An eight-week mindfulness meditation program is feasible for older adults aged 65 and older with chronic low back pain. In this pilot randomized trial, 37 participants were assigned to either the meditation program or a wait-list control. At the end of the intervention, 81% completed assessments, average class attendance was 6.7 out of 8 sessions, and participants meditated about 4.3 days per week for an average of 31.6 minutes per day. Compared to the control group, the meditation group showed significant improvements in pain acceptance (specifically the total score and activities engagement subscale) and physical function. The program may lead to better pain acceptance and physical function.
Pain
April 1, 2000
Thomas Graven‐nielsen, Sally Kendall, Karl G. Henriksson et al.
409 citations
In people with fibromyalgia syndrome, an NMDA antagonist (ketamine) reduced pain at rest, decreased pain intensity and the spread of referred pain from an experimental muscle injection, and increased pressure pain tolerance at tender points. Ketamine also reduced the difference between pain thresholds to single versus repeated electrical stimuli, indicating a specific effect on temporal summation of pain signals. The findings suggest that central nervous system hyperexcitability contributes to referred pain and temporal summation in a subgroup of fibromyalgia patients, though whether this is unique to fibromyalgia or common in other painful musculoskeletal conditions remains unknown.
Pain
October 29, 2012
Marco L. Loggia, Jieun Kim, Randy L. Gollub et al.
319 citations
Patients with chronic low back pain show stronger resting connectivity between the default mode network and the right insula, pregenual anterior cingulate cortex, and left inferior parietal lobule compared to healthy controls. Baseline clinical pain correlates positively with default mode network–right insula connectivity. Physical maneuvers that exacerbate pain produce parallel changes in default mode network–right insula connectivity and disrupt default mode network–pregenual anterior cingulate cortex connectivity, which at baseline was anticorrelated with pain. Baseline default mode network connectivity also predicts maneuver-induced changes in both pain and default mode network–right insula connectivity. These findings support resting default mode network connectivity as a potential neuroimaging biomarker for chronic pain perception.
Pain
September 5, 2022
Matthew Lyes, Joel Castellanos, Timothy Furnish et al.
55 citations
Three individuals with chronic neuropathic pain, unresponsive to standard treatments and impairing quality of life, self-administered low doses of psilocybin. Despite differences in pain origin and preparation potency, all three achieved substantial pain relief without experiencing a psychedelic state or significant side effects. The analgesic effect was enhanced when combined with functional exercise, and in one case, repeated dosing appeared to increase relief, hinting at a possible long-term plasticity-mediated effect. The patients also reduced their reliance on conventional pain medications. These observations suggest psilocybin's therapeutic potential for chronic pain deserves further study.
Pain
March 1, 1988
Per Kristian Eide, Kjell Hole
21 citations
Acute doses of serotonin-uptake inhibitors (zimelidine, alaproclate, chlorimipramine) produced pain relief in mice on the hot-plate test but not the tail-flick test. After chronic treatment and withdrawal, tail-flick latencies shortened—indicating increased pain sensitivity—at multiple time points for each drug. Hot-plate response temperatures were slightly lowered only after chronic zimelidine. The drugs did not alter the response to a serotonin-receptor agonist after a single dose, but after withdrawal of chronic treatment, the response increased in the tail-flick test only. The authors conclude that acute and chronic treatment with these drugs modulate pain differently, and that chronic treatment leads to supersensitivity of spinal serotonin receptors, with test-dependent effects possibly due to different serotonin-receptor subtypes.
Pain
October 1, 2023
Jonathan N Davies, Ben Colagiuri, Louise Sharpe et al.
15 citations
A single 20-minute online mindfulness session did not reduce chronic pain intensity or unpleasantness more than sham mindfulness or a general sham condition in 169 adults with chronic or recurrent pain. All three active conditions reduced pain unpleasantness compared to an audiobook control, and this effect was most strongly linked to participants' expectations (placebo). No evidence was found that mindfulness engages its theorized specific processes. The findings suggest that short-term pain relief from a single mindfulness session may be driven by placebo effects rather than mindfulness-specific mechanisms.
Pain
September 1, 2024
Yang Zhou, Wanchen Sun, Yuxuan Fu et al.
9 citations
Moderate-to-severe acute postsurgical pain after spinal surgery can slow recovery. A combination of esketamine and pregabalin reduced the incidence of such pain from 60.5% to 27.3% in the first 48 hours after surgery, based on a randomized trial of 90 patients undergoing resection of spinal neoplasms. The odds ratio was 0.25, indicating a substantial benefit. However, mild dissociative symptoms occurred in 18.2% of the combination group versus none in the control group, suggesting the analgesic strategy carries this risk.
Pain
February 1, 2025
James Gerhart, John W Burns, Beverly Thorn et al.
3 citations
For chronic low back pain, cognitive therapy, mindfulness-based stress reduction, and behavior therapy all appear to work by progressively weakening the link between pain-related thoughts or pain spikes and later outcomes, rather than by directly changing those mechanisms. In a study of 521 people, associations between treatment mechanism variables and outcomes were strong early in treatment but became nonsignificant by the final third. This decoupling effect was similar across the three active treatments but did not occur in treatment as usual. The findings suggest that by midtreatment, participants may learn that maladaptive thoughts or pain increases need not worsen their subsequent experience.