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Joel Katz

Publications and source records attributed to Joel Katz.

At least 19 recordsLinked to original sources
PubMed2026

Ketamine assisted psychotherapy to reduce chronic neuropathic pain: A mixed-methods randomized pilot trial.

BACKGROUND: Intravenous ketamine can provide short-term analgesia in chronic neuropathic pain but benefits often wane after treatment. We conducted a randomized pilot trial to assess the feasibility of combining ketamine infusions with psychotherapy to inform future efficacy trials. METHODS: In this single-center, randomized, outcome-assessor-blinded pilot trial at a Canadian tertiary pain clinic, adults with moderate-to-severe chronic neuropathic pain were randomly assigned in 1:1:1 ratio to the ketamine, psychotherapy, or combined ketamine plus psychotherapy arm. Ketamine was delivered as three intravenous infusions over 16 weeks; psychotherapy consisted of 16 weekly cognitive behavioral therapy and mindfulness-based meditation sessions. The primary outcome was feasibility, assessed using prespecified progression criteria. Exploratory outcomes included changes in pain interference (PROMIS 6a T-score), pain intensity, mood, and qualitative interview findings at week 20 (ClinicalTrials.gov: NCT05639322). FINDINGS: Between October 23, 2023, and March 31, 2025, 30 participants were randomized, and 26 (87%) completed 20-week follow-up. Most feasibility criteria, including consent, retention, data completeness, and absence of study-related serious adverse events, were met; adherence targets were partially met. Exploratory pain outcomes showed numerical improvement across groups, with clinically meaningful reductions observed for pain interference and pain intensity. Sixty-four adverse events were recorded, mostly mild and in ketamine-containing groups; no serious study-related adverse events occurred. CONCLUSIONS: Combined ketamine and psychotherapy was feasible and acceptably safe in this pilot trial, supporting evaluation in a larger efficacy-powered study. FUNDING: The study was funded by the St. Michael's Hospital Innovation Fund, The Canadian Pain Society Early Investigator Award and the Physician Services Incorporation Early Career Researcher Award.

Humans↗
PubMed2006

Children with chronic pain: impact of sex and age on long-term outcomes.

The present study examined the long-term pain and disability outcomes of a pediatric chronic pain clinic cohort and evaluated whether these outcomes differed by age and sex. Patients were interviewed a mean of 3 years after their last appointment at a pediatric pain clinic. The cohort comprised 95 females and 48 males, aged 5-23 years when interviewed. Of the cohort, 62.2% (67 females, 22 males) reported continuing pain. Females were significantly more likely than males to report continuing pain (OR=2.9, 95% CI=1.4-5.8, p=.005), use of health care (OR=5.1, 95% CI=1.4-18.5, p=.01), medication (OR=4.7, 95% CI=1.3-16.9, p=.02) and non-drug methods of pain control (OR=3.4, 95% CI=1.3-9.2, p=.02). For patients whose pain had associated psychosocial factors, females (76.4%) were significantly more likely than males (21.4%) to report continuing pain (OR=13.8, 95% CI=3.3-58.4, p=.005). Finally, among patients still experiencing pain, the frequency of pain episodes increased significantly with age (OR=1.3, 95% CI=1.0-1.5, p=.02). Results indicate that chronic pain persists for many children despite treatment at specialized clinics. Females may be at higher risk for continuing pain and report greater use of health care, medication, and non-drug methods of pain control.

Adolescent↗
PubMed2006

The role of work stress as a moderating variable in the chronic pain and depression association.

OBJECTIVE: This article aims to examine the role of work stress as a moderating variable in the chronic pain-depression association, as well as sex differences in this link. METHODS: The analyses were carried out using the Canadian Community Health Survey Cycle 1.1. Key variables were chronic pain conditions (fibromyalgia, arthritis/rheumatism, back problems, and migraine headaches), work stress, and depression. The total sample comprises 78,593 working individuals. RESULTS: In this working sample, 7.6% met criteria for major depression, but the prevalence increased to 12% in those also reporting chronic pain. Both depression and comorbid chronic pain and depression were twice as prevalent in women as in men. Having a chronic pain condition and overall work stress emerged as the strongest predictors of depression. Unexpectedly, however, none of the work stress domains moderated the chronic pain and depression association. CONCLUSION: The impact of work stress should be considered in the etiology and management of major depression.

Adult↗
PubMed2006

Internal medicine and general surgery residents' attitudes about the ACGME duty hours regulations: a multicenter study.

PURPOSE: To assess internal medicine and general surgery residents' attitudes about the effects of the Accreditation Council for Graduate Medical Education duty hours regulations on medical errors, quality of patient care, and residency experiences. METHOD: In 2005, the authors surveyed 200 residents who trained both before and after duty hours reform at six residency programs (three internal medicine, three general surgery) at five academic medical centers in the United States. Residents' attitudes about the effects of the duty hours regulations on the quality of patient care, residency education, and quality of life were measured using a survey instrument containing 19 Likert scale questions on a scale of 1 to 5. Survey responses were compared using the Student's t-test. RESULTS: The response rate was 80% (159 residents). Residents reported that whereas fatigue-related errors decreased slightly, errors related to reduced continuity of care significantly increased. Additionally, duty hours regulations somewhat decreased opportunities for formal education, bedside learning, and procedures, but there was no consensus that graduates would be less well trained after duty hours reform. Residents, particularly surgical trainees, reported improvements in quality of life and reduced burnout. CONCLUSIONS: Residents in medicine and surgery had similar opinions about the effects of duty hours reform, including improved quality of life. However, resident opinions suggest that reduced fatigue-related errors have been offset by errors related to decreased continuity of care and that the quality of the educational experience may have declined. Quantifying the degree to which regulating duty hours affected errors related to discontinuity of care should be a focus of future research.

Attitude↗
PubMed2006

A survey of the pain experienced by males and females with Fabry disease.

BACKGROUND: The clinical onset of Fabry disease, a rare, X-linked, multisystemic disorder, is marked by neuropathic pain. Males suffer extensively from this disease. Females, as genetic 'carriers', have traditionally been viewed as either asymptomatic or mildly afflicted with this disease. OBJECTIVES: To describe Fabry-related pain and compare experiences between the sexes. Patients' perceptions of physician pain assessments were also examined. METHODS: A disease-specific questionnaire was accessible on-line (www.fabry.org) and mailed to 552 members of a Fabry disease support group. RESULTS: The response rate was 14.3% for the support group-based mail questionnaire. Females (58.0%) were significantly older (mean +/- SD 45.9+/-13.5 years) than males (mean +/- SD 40.0+/-12.1; t [86]=-2.11, P<0.05). Females were diagnosed with Fabry disease later (31.1+/-14.0 years) than males (24.2+/-11.9 years; t [86]=-2.43, P<0.05). Females (mean score for pain disability rating 3.0+/-1.4) suffered more extensive disability from migraine pain (mean score 2.2+/-1.3; F [1, 74]=45.0, P<0.005), and, unlike males, did not exhibit a decline in pain intensity with disease duration. Satisfaction with physician pain assessments was moderate. CONCLUSIONS: Contrary to the traditional view of females as carriers, females with Fabry disease experienced intense disease-related pain; pain produced comparable distress and impairment in both sexes. The diagnostic delay and absence of a decline in pain symptoms over time in females suggest additional disease burden. Females may be triply disadvantaged in the health care system due to disease rarity, devalued carrier status and sex.

Adult↗
PubMed2006

A novel training model to address health problems in poor and underserved populations.

Health disparities are increasingly common and many U.S. practitioners have informal experience working in resource-poor settings. There are, however, few graduate medical education programs that focus on health equity. A graduate medical education program in health equity was developed at Brigham and Women's Hospital based on a review of existing literature and on a survey of junior faculty who have had informal health disparities experience. The Howard Hiatt Residency in Global Health Equity and Internal Medicine was developed as a four-year program to provide intensive training in internal medicine and health disparities. Participating residents are matched with a mentor who has clinical and research experience in the field of global health. In addition to a series of didactic teaching sessions and longitudinal seminars that focus on issues of global health equity, residents take graduate level courses in epidemiology, health policy, ethics, and medical anthropology. Residents also carry out an independent research project in a geographic area that suffers from health disparities. Two residents are selected for training per year. Participating faculty are multidisciplinary and come from diverse Harvard-affiliated institutions. Graduate medical education in the United States with a focus on health equity is lacking. It is hoped that the novel training program in health equity for internal medical residents developed at Brigham and Women's Hospital can serve as a model for other teaching hospitals based in the United States.

Curriculum↗
PubMed2005

Dissociation of phantom limb phenomena from stump tactile spatial acuity and sensory thresholds.

Most amputees experience phantom limb sensations and/or phantom limb pain as well as residual limb (stump) pain that are resistant to treatment. Phantom phenomena are not homogeneous; each patient presents with a unique combination of spontaneous or evoked sensations, pain, and/or awareness. In an effort to understand the underlying mechanisms, postamputation pain has been subclassified based on the perceived sensory qualities reported by the individual. However, little is known about the relationship between subjective phantom phenomena and sensory function of the residual stump. The aim of the present study was to determine if sensory processing, as measured psychophysically, reflected subjective reports of specific qualities of phantom and/or stump sensory phenomena. Twelve individuals who had recently (within 6 months) undergone traumatic unilateral upper extremity amputation participated in the study. Limb temperature, thermal thresholds, tactile sensory thresholds and tactile spatial acuity were compared between the residual limb and the intact limb, and related to patient reports of specific stump and phantom sensory phenomena. All but one subject reported phantom sensations and/or phantom pain. The remaining subject reported only stump pain. Mean skin temperature of the residual limb was significantly lower than that of the intact contralateral limb by approximately 0.9 degrees C in the proximal portion of the stump and 1.7 degrees C at the stump tip. However, the temperature of the stump (compared with the intact limb) did not reflect subjective reports of stump or phantom limb thermal characteristics. Thermal threshold abnormalities differed among patients, and did not suggest any pattern of small fibre loss of function or generalized hyperexcitability. Other than within grafted tissue or near the scar area, skin areas that the patient described as abnormally sensitive or tender to touch were not accompanied by corresponding abnormalities in static tactile thresholds or tactile spatial acuity. Tactile spatial acuity was heightened near the scar area only. The proportion of subjects who had decreased two-point discrimination thresholds at the stump did not differ significantly according to the reporting or non-reporting of dual percepts. Thus, despite a common injury, the sensory abnormalities varied within this cohort of subjects. In addition, psychophysical threshold measures of sensory function did not reflect, in any simple way, subjective phantom phenomena. Therefore, classification of phantom phenomena based on peripheral sensory function may be a misleading step in the search for specific mechanisms underlying postamputation sensory phenomena.

Adult↗
PubMed2005

Preoperative coping strategies and distress predict postoperative pain and morphine consumption in women undergoing abdominal gynecologic surgery.

OBJECTIVES: The aim of the present study was to predict postoperative pain and morphine consumption based on preoperative psychosocial factors. METHODS: One hundred and twenty-two women completed measures of distress and coping 1 week before major abdominal gynecological surgery by laparotomy. Forty-eight hours after surgery, measures of pain and negative affect (NA) were completed, and morphine consumption was recorded from a patient-controlled analgesia pump. Four weeks after surgery, measures of pain and NA were completed. RESULTS: Multivariate analyses revealed that preoperative self-distraction coping (P=.039) positively predicted postoperative pain levels in the hospital, after accounting for the effects of age, concurrent NA, and morphine consumption. Emotional support (P=.031) and religious-based coping (P=.036) positively predicted morphine consumption in the hospital, after accounting for the effects of age, concurrent NA, and pain levels. Preoperative distress (P<.04 to .008) and behavioral disengagement (P=.034), emotional support (P=.049), and religious-based coping (P=.001) positively predicted pain levels 4 weeks after surgery, after accounting for the effects of age and concurrent NA. CONCLUSION: The results suggest that preoperative psychosocial factors are associated with postoperative pain and morphine consumption.

Adaptation, Psychological↗
PubMed2005

The effects of early pain experience in neonates on pain responses in infancy and childhood.

Iatrogenic pain is commonplace in newborn infants yet we know very little about its long-term effects. This article reviews the evidence for and against the suggestion that painful procedures experienced in the perinatal period influence subsequent pain responses in infancy or in childhood. The evidence suggests that early experiences with pain are associated with altered pain responses later in infancy. The direction of the altered response depends, in part, on the infant's developmental stage (full-term vs preterm), and his or her cumulative experience with pain. Preterm infants that are hospitalized as neonates and subjected to painful procedures appear to have a dampened response to painful procedures later in infancy. Full-term neonates exposed to extreme stress during delivery, or to a surgical procedure, react to later noxious procedures with heightened behavioral responsiveness. Studies in which analgesic agents (local anesthetics or opioids) have been administered prior to noxious procedures demonstrate less procedural pain and a reduction in the magnitude of long-term changes in pain behaviors. The precise determinants of these changes, their extent, and their permanence are not known but they appear to involve noxious stimulus-induced peripheral and central sensitization, as well as classical conditioning.

Analgesics↗
PubMed2004

Pain, opioid tolerance and sensitisation to nociception in the neonate.

Pain is commonplace in newborn infants. Opioid analgesics have become increasingly used to reduce different types of pain in neonates, including pain from surgery, medical procedures and chronic conditions. Adverse effects of opioids include respiratory depression, hypotension and tolerance. These adverse effects can be minimised by utilising specific administration techniques and constant monitoring. Recent studies have demonstrated that untreated pain can have long-term effects on infant pain behaviours months beyond the events, thus, opioid analgesics may have a beneficial role that extends beyond the immediate painful event(s).

Analgesics, Opioid↗
PubMed2004

Impact of preoperative education on pain outcomes after coronary artery bypass graft surgery.

Cardiovascular diseases cause more disability and economic loss in industrialized nations than any other group of diseases. In previous work [Nurs Res 49 (2000a) 1], most coronary artery bypass graft patients (CABG, N=225 ) reported unrelieved pain and received inadequate analgesics. This study proposed to evaluate a preadmission education intervention to reduce pain and related activity interference after CABG surgery. Patients (N=406) were randomly assigned to (a) standard care or (b) standard care+pain booklet group. Data were examined at the preadmission clinic and across days 1-5 after surgery. Outcomes were pain-related interference (BPI-I), pain (MPQ-SF), analgesics (chart), concerns about taking analgesics (BQ-SF), and satisfaction (American Pain Society-POQ). The impact of sex was explored related to primary and secondary outcomes. The intervention group did not have better overall pain management although they had some reduction in pain-related interference in activities ( t(355)=2.54, P<0.01) and fewer concerns about taking analgesics ( F(1,313)=2.7, P<0.05) on day 5. Despite moderate 24-h pain intensity across 5 days, patients in both groups received inadequate analgesics (i.e. 33% prescribed dose). Women reported more pain and pain-related interference in activities than men. The booklet was rated as helpful, particularly by women. In conclusion, the intervention did not result in a clinically significant improvement in pain management outcomes. In future, an intervention that considers sex-specific needs and also involves educating the health professionals caring for these patients may influence these results.

Aged↗
PubMed2004

Pre-emptive analgesia using intravenous fentanyl plus low-dose ketamine for radical prostatectomy under general anesthesia does not produce short-term or long-term reductions in pain or analgesic use.

The aim of the study was to evaluate post-operative pain and analgesic use after pre-operative or post-incisional i.v. fentanyl plus low dose i.v. ketamine vs. a standard treatment receiving i.v. fentanyl but not ketamine. Men undergoing radical prostatectomy under general anesthesia were randomly assigned in a double-blinded manner to one of three groups. Patients received i.v. fentanyl before incision followed by an i.v. bolus dose (0.2 ml kg(-1)) and an i.v. infusion (0.0025 ml kg(-1)min(-1)) of 1 mg ml(-1) ketamine (group 1) or normal saline (groups 2 and 3). Seventy minutes after incision, patients received i.v. fentanyl followed by an i.v. bolus dose (0.2 ml kg(-1)) and an i.v. infusion (0.0025 ml kg(-1)min(-1)) of saline (groups 1 and 3) or ketamine (group 2). Pain, von Frey pain thresholds, and cumulative morphine consumption using patient-controlled analgesia (PCA) were assessed up to 72 h after surgery. 143 patients completed the study (group 1, n = 47, group 2, n = 50, group 3, n = 46). Cumulative PCA morphine (mean+/-SD) did not differ significantly among groups (group 1, 92.3+/-45.9 mg; group 2, 107.2+/-58.4 mg; group 3, 103.6+/-50.4 mg; P = 0.08 for groups 1 vs. 2, and groups 1 vs. 3). On day 3, the hourly rate (mean+/-SEM) of morphine consumption was significantly lower (p < 0.0009) in group 1 (0.61+/-0.013 mg h(-1)) than group 2 (0.86+/-0.011 mg h(-1)) and group 3 (0.89+/-0.008 mg h(-1)). Pain scores and von Frey pain thresholds did not differ significantly among groups. Two-week and 6-month follow-ups did not reveal significant group differences in pain incidence, intensity, disability or mental health. Pre-operative, low-dose administration of i.v. ketamine did not result in a clinically meaningful reduction in pain or morphine consumption when compared with post-incisional administration of ketamine or a saline control condition.

Aged↗
PubMed2004

Effects of perioperative oral amantadine on postoperative pain and morphine consumption in patients after radical prostatectomy: results of a preliminary study.

BACKGROUND: Amantadine is known to be a noncompetitive N-methyl-D-aspartate receptor antagonist and may be useful in preventing postoperative central sensitization, acute opioid tolerance, and opioid-induced hyperalgesia, thereby decreasing pain and analgesic requirements. The aim of this pilot study was to evaluate the effects of perioperative oral amantadine on postoperative pain and analgesic consumption. METHODS: Twenty-four patients scheduled to undergo radical prostatectomy were given oral amantadine before and after surgery in a randomized, double-blind, placebo-controlled manner. After surgery, patients received intravenous patient-controlled analgesia with morphine for 48 h. Wound pain intensity, sensitivity to mechanical pressure around the surgical wound, and incidence of bladder spasm pain were assessed. Blood samples were drawn for analysis of amantadine, morphine, and the morphine metabolites. Adverse effects and patient satisfaction were assessed. RESULTS: The cumulative morphine consumption was significantly lower in the amantadine group at all time points (except at 48 h), amounting to a 32% reduction over the 48-h period. Forty-eight hours after surgery, visual analog pain scores to pressure applied near the wound were significantly lower in the amantadine group than in the placebo group. In addition, the number of patients reporting bladder spasm pain was significantly lower in the amantadine group. Plasma concentration of morphine-3-glucuronide was significantly lower at the end of surgery in the amantadine group. Pharmacokinetic analyses showed that the plasma clearance of morphine at 22-24 h after surgery was also significantly lower in the amantadine group. CONCLUSION: The results suggest that perioperative oral amantadine reduces postoperative opioid consumption by pharmacokinetic mechanisms, although additional pharmacodynamic interactions may also be involved.

Adolescent↗
PubMed2004

Preventive analgesia is associated with reduced pain disability 3 weeks but not 6 months after major gynecologic surgery by laparotomy.

BACKGROUND: Most studies of preemptive or preventive analgesia restrict outcomes to pain and analgesic consumption in the acute postoperative period. The potential longer-term effects on these and other domains of functioning have received little empirical attention. The purpose of this study was to follow up patients who had received general anesthesia plus epidural fentanyl and lidocaine before (group 1) or after (group 2) incision or general anesthesia plus a sham epidural (group 3). METHODS: Patients were contacted approximately 3 weeks and 6 months after surgery. A follow-up pain questionnaire and the McGill Pain Questionnaire were administered by telephone. The Mental Health Inventory and Pain Disability Index were mailed to patients, completed, and mailed back. RESULTS: One hundred thirty-one of the 141 patients (93%) were reached 3 weeks after surgery (n = 41, n = 48, and n = 42 in groups 1, 2, and 3, respectively), and 109 (77%) were reached at 6 months (n = 35, n = 37, and n = 37 in groups 1, 2, and 3, respectively). Multivariate analysis of covariance indicated that that even after controlling for age and presence or absence of preoperative pain, Pain Disability Index scores (mean +/- SD) at the first follow-up were significantly lower in group 1 (17.3 +/-12.8) and group 2 (18.1 +/-17.0) compared with group 3 (26.3 +/- 18.3). McGill Pain Questionnaire and Mental Health Inventory scores did not differ significantly among the groups. There were no significant differences at the 6-month follow-up. CONCLUSION: The short-term beneficial effects of preventive epidural analgesia translated into less pain disability 3 weeks after surgery. Progress in understanding the processes involved in postsurgical recovery and the risk factors for chronic postsurgical pain would be aided by baseline and postsurgical measures of relevant psychological, emotional, and physical variables.

Adaptation, Psychological↗
PubMed2004

Early but no long-term benefit of regional compared with general anesthesia for ambulatory hand surgery.

BACKGROUND: The purpose of this study was to determine whether either regional anesthesia (RA) or general anesthesia (GA) provided the best analgesia with the fewest adverse effects up to 2 weeks after ambulatory hand surgery. METHODS: Patients undergoing ambulatory hand surgery were randomly assigned to RA (axillary brachial plexus block; n = 50) or GA (n = 50). Before surgery, all patients rated their hand pain (visual analog scale) and pain-related disability (Pain-Disability Index). After surgery, eligibility for bypassing the postanesthesia care unit ("fast track") was determined, and pain, adverse effects, and home-readiness scores were measured. On postoperative days 1, 7, and 14, patients documented their pain, opioid consumption, adverse effects, Pain-Disability Index, and satisfaction. RESULTS: More RA patients were fast-track eligible (P < 0.001), whereas duration of stay in the postanesthesia care unit was shorter in the RA group (P < 0.001). Time to first analgesic request was longer in the RA group (P < 0.001), and opioid consumption was reduced before discharge (P < 0.001). In the RA group, the pain ratings measured at 30, 60, 90, and 120 min after surgery were lower (P < 0.001), and patients spent less time in the hospital after surgery (P < 0.001). More GA patients experienced nausea/vomiting during recovery in the hospital (P < 0.05). However, on postoperative days 1, 7, and 14, there were no differences in pain, opioid consumption, adverse effects, Pain-Disability Index, or satisfaction. CONCLUSIONS: Despite significant reduction in pain before discharge from the hospital after ambulatory hand surgery, single-shot axillary brachial plexus block does not reduce pain at home on postoperative day 1 or up to 14 days after surgery when compared with GA. However, RA does provide other significant early benefits, including reduction in nausea and faster discharge from the hospital.

Adult↗
PubMed2004

Impact of attending a health care conference in Toronto during the severe acute respiratory syndrome crisis: survey of delegates.

OBJECTIVE: To describe the impact on delegates of attending the Canadian Pain Society's annual meeting in Toronto during the severe acute respiratory syndrome (SARS) crisis in May 2003. METHODS: A prospective survey design was used. Surveys were sent to all delegates (n=432) who attended the conference, and 294 delegates responded (68% response rate). The survey was developed to determine the level of concern about travelling to Toronto; the adequacy of screening measures; the level of stress about attending; and the occupational consequences of attending. RESULTS: Fifty per cent of the participants were not concerned about travelling to Toronto, while the other 50% expressed some concern ranging from mild to serious. Concerns included being exposed to SARS and fear of transmitting it to others upon return. Reasons for attending the conference despite concern included a desire for continuing education, decrease in the number of reported SARS cases, and perceived minimal risk. Almost one-half (n=140) felt the screening measures at the conference were adequate, while 4% felt they were inadequate and 9% somewhat adequate. Delegates (n=99) suggested that temperature-taking (32.2%), improved screening vigilance (14.4%), SARS screening forms checked daily (9.1%), strictly controlled entry (8.1%) and adopting hospital screening procedures (7.1%) should have been instituted. CONCLUSION: Health care professionals planning conferences in this era of new respiratory diseases can benefit from understanding the responses of delegates who attended conferences during outbreaks. Clear communication about the potential risks and benefits, as well as instituting full screening precautions, will help to allay concerns.

Adolescent↗
PubMed2004

A qualitative systematic review of the role of N-methyl-D-aspartate receptor antagonists in preventive analgesia.

UNLABELLED: We evaluated in a qualitative systematic review the effect of N-methyl-D-aspartate (NMDA) receptor antagonists on reducing postoperative pain and analgesic consumption beyond the clinical duration of action of the target drug (preventive analgesia). Randomized trials examining the use of an NMDA antagonist in the perioperative period were sought by using a MEDLINE (1966-2003) and EMBASE (1985-2003) search. Reference sections of relevant articles were reviewed, and additional articles were obtained if they evaluated postoperative analgesia after the administration of NMDA antagonists. The primary outcome was a reduction in pain, analgesic consumption, or both in a time period beyond five half-lives of the drug under examination. Secondary outcomes included time to first analgesic request and adverse effects. Forty articles met the inclusion criteria (24 ketamine, 12 dextromethorphan, and 4 magnesium). The evidence in favor of preventive analgesia was strongest in the case of dextromethorphan and ketamine, with 67% and 58%, respectively, of studies demonstrating a reduction in pain, analgesic consumption, or both beyond the clinical duration of action of the drug concerned. None of the four studies examining magnesium demonstrated preventive analgesia. IMPLICATIONS: We evaluated, in a qualitative systematic review, the effect of N-methyl D-aspartate antagonists on reducing postoperative pain and analgesic consumption beyond the clinical duration of action of the target drug (preventive analgesia). Dextromethorphan and ketamine were found to have significant immediate and preventive analgesic benefit in 67% and 58% of studies, respectively.

Analgesics, Opioid↗