Effects of Ketamine on Postoperative Pain After Remifentanil-Based Anesthesia for Major and Minor Surgery in Adults: A Systematic Review and Meta-Analysis

Effect of Different Doses of Esketamine on Postoperative Recovery in Patients Undergoing Gynecologic Laparoscopic Surgery, a Randomized, Double-Blind, Single-Center Clinical Study

Purpose

This study aimed to explore the effect of preoperative different doses of esketamine on postoperative recovery in patients undergoing gynecologic laparoscopic surgery.

Methods

A total of 99 women scheduled for gynecologic laparoscopic surgery under general anesthesia were enrolled and randomized. Three minutes before surgical incision, patients in the three groups were intravenously administered 0.25 mg/kg esketamine, 0.5 mg/kg esketamine, and an equivalent dose of saline, respectively. The primary outcome was the Quality of Recovery-15 (QoR-15) score assessed on 1 day (pod1), 3 days (pod3), and 7 days postoperatively (pod7). Secondary outcomes encompassed the VAS score, MAP, HR, frequency of rescue analgesia and length of hospital stay.

Results

Compared with group C, QoR-15 score was significantly improved in group E1 and E2 on pod1, while the rest VAS score was significantly decreased at 6h postoperatively (F =19.164, P < 0.001; F = 6.059, P = 0.034). On pod1, the VAS scores at rest and movement in group E2 were significantly lower than those in group C (P = 0.007, P = 0.038). There was a significant decrease in resting VAS scores in the E2 group compared with group C on pod3 (P = 0.021). Compared with group C, the QoR-15 score in group E2 increased on pod7 (P = 0.008), but there was no clinical difference. There was no significant difference in MAP and HR among the three groups at each time point (F = 0.758, P = 0.471; F = 0.232, P = 0.794). There was a significant difference in the number of postoperative rescue analgesia among the three groups (P = 0. 023).

Conclusion

Preoperative single small dose of esketamine can improve the quality of recovery 24h after gynecologic laparoscopic surgery patients, decrease the number of rescue analgesia, and may contribute to the rapid recovery of patients. And 0.5 mg/kg esketamine seems to be better.

Effects of Virtual Reality on Preoperative Anxiety in Adult Patients: An Updated Meta-analysis

PURPOSE

To determine the effectiveness of virtual reality (VR) on preoperative anxiety in adult patients.

DESIGN

A systematic review and meta-analysis of randomized controlled trials.

METHODS

A systematic search was carried out using PubMed, Web of Science, the Cochrane Library, Embase, CINAHL, Scopus, PsycINFO, China National Knowledge Infrastructure (CNKI), WANFANG DATA, Chinese Science and Technology Periodical Database (VIP), and Sino-Med from inception to December 18, 2022. All eligible randomized controlled trials published were included (published in English and Chinese). The Cochrane Collaboration "Risk of Bias" tool was used to assess the methodological quality of the included studies. Review Manager software 5.4 was used for data analysis.

FINDINGS

Nine studies with sample sizes ranging from 72 to 255 and 1,046 participants were identified. The results of the meta-analysis showed that VR significantly reduced preoperative anxiety in adults (standardized mean difference = -0.48, 95% CI: -0.93 to -0.03, P = .04). Our results suggested that VR improved postoperative satisfaction scores more effectively compared with control care (mean difference = 15.29, 95% CI: 6.25 to 24.33, P = .0009).

CONCLUSIONS

Study results support that VR has a positive effect in reducing preoperative anxiety in adults. VR can also significantly improve patients' satisfaction after surgery. However, the results need to be further assessed due to the small sample sizes and high heterogeneity.

Navigating the Postoperative Management of Remifentanil-Induced Hyperalgesia: A Case Report

Opioid induced hyperalgesia in the postoperative setting presents a significant challenge for clinicians managing postoperative pain in opioid tolerant patients. Remifentanil is a fentanyl analog frequently utilized in anesthesia for its favorable pharmacokinetic profile. However, as described in the case report, it may also increase the risk of postoperative hyperalgesia. Management of postoperative pain in the setting of hyperalgesia should be approached in a stepwise fashion, emphasizing therapy options with analgesic effects achieved outside of the opioidergic system while maintaining a neutral opioid balance.

Remifentanil-induced hyperalgesia in healthy volunteers: a systematic review and meta-analysis of randomized controlled trials

ABSTRACT

Recent literature suggests that the withdrawal of remifentanil (RF) infusion can be associated with hyperalgesia in clinical and nonclinical settings. We performed a systematic review and a meta-analysis of randomized controlled trials with cross-over design, to assess the effect of discontinuing RF infusion on pain intensity and areas of hyperalgesia and allodynia in healthy volunteers. Nine studies were included. The intervention treatment consisted in RF infusion that was compared with placebo (saline solution). The primary outcome was pain intensity assessment at 30 ± 15 minutes after RF or placebo discontinuation, assessed by any pain scale and using any quantitative sensory testing. Moreover, postwithdrawal pain scores were compared with baseline scores in each treatment. Secondary outcomes included the areas (% of basal values) of hyperalgesia and allodynia. Subjects during RF treatment reported higher pain scores after discontinuation than during treatment with placebo [standardized mean difference (SMD): 0.50, 95% confidence interval (CI): 0.03-0.97; P = 0.04, I 2 = 71%]. A significant decrease in pain scores, compared with baseline values, was found in the placebo treatment (SMD: -0.87, 95% CI: -1.61 to -0.13; P = 0.02, I 2 = 87%), but not in the RF treatment (SMD: -0.28, 95% CI: -1.18 to 0.62; P = 0.54, I 2 = 91%). The area of hyperalgesia was larger after RF withdrawal (SMD: 0.55; 95% CI: 0.27-0.84; P = 0.001; I 2 = 0%). The area of allodynia did not vary between treatments. These findings suggest that the withdrawal of RF induces a mild but nonclinically relevant degree of hyperalgesia in HVs, likely linked to a reduced pain threshold.

Effect of opioid-free anesthesia on post-operative period in cytoreductive surgery with hyperthermic intraperitoneal chemotherapy: a propensity score matched study

BACKGROUND

Postoperative pain after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is important. It appears essential to reduce postoperative pain and morphine consumption.

METHODS

Retrospective study in a university hospital comparing patient benefiting from CRS-HIPEC under opioid-free anesthesia (OFA; dexmedetomidine) to those anesthetized with opioid anesthesia (OA; remifentanil) using a propensity score matching method. The main objective was the impact of OFA on postoperative morphine consumption in the first 24 h after surgery.

RESULTS

102 patients were included, matching on the propensity score allowed selecting 34 unique pairs analyzed. Morphine consumption was lower in the OFA group than in the OA group (3.0 [0.00-11.0] mg/24 h vs. 13.0 [2.5-25.0] mg/24 h; p = 0.02). In multivariable analysis, OFA was associated with a reduction of 7.2 [0.5-13.9] mg of postoperative morphine (p = 0.04). The rate of renal failure with a KDIGO-score > 1 was lower in the OFA group than in the OA group (12% vs. 38%; p = 0.01). There was no difference between groups concerning length of surgery/anesthesia, norepinephrine infusion, volume of fluid therapy, post-operative complications, rehospitalization or ICU readmission within 90 days, mortality, and postoperative rehabilitation.

CONCLUSION

Our results suggest that OFA for CRS-HIPEC patients appears safe and is associated with less postoperative morphine use and acute kidney injury.

Efficacy of nonopioid analgesics and regional techniques for perioperative pain management in laparoscopic gynecological surgery: a systematic review and network meta-analysis

BACKGROUND

The optimal approach for perioperative pain management in laparoscopic gynecological surgery is unclear due to a lack of comprehensive analysis, which limits the development of evidence-based enhanced recovery after surgery protocols. This study aimed to conduct a systematic review and network meta-analysis to support clinical decision-making for optimal analgesia.

MATERIALS AND METHODS

This study conducted a systematic literature search in PubMed, Embase, CENTRAL, Web of Science, and CINAHL from inception to 3 December 2021, and updated on 19 August 2022. Randomized controlled trials comparing the perioperative use of nonopioid analgesics and regional techniques in adults undergoing elective laparoscopic gynecological surgery under general anesthesia were included in the analysis, either alone or in combination. The co-analgesic interventions during the perioperative period for the intervention and control groups of each eligible study were also considered. We assessed the risk of bias using the Risk of Bias 2 tool and evaluated the certainty of evidence using the Confidence in Network Meta-Analysis (CINeMA) approach. A Bayesian network meta-analysis was used to estimate the efficacy of the analgesic strategies. The primary outcomes were pain score at rest and cumulative oral morphine milligram equivalents at 24 h postoperatively.

RESULTS

Overall, 108 studies with 9582 participants and 35 different interventions were included. Compared with inert treatments, combinations of two or more interventions showed better efficacy and longer duration in reducing postoperative pain and opioid consumption within 24 h than monotherapies, and showed stepwise enhanced effects with increasing analgesic modes. In combination therapies, regional techniques that included peripheral nerve blocks and intraperitoneal local anesthetics, in combination with nonopioid systemic analgesics, or combining local anesthetics with adjuvant drugs, were found to be more effective. Monotherapies were found to be mostly ineffective. The most effective peripheral nerve blocks were found to be ultrasound-guided transversus abdominis plane block with adjuvant and ultrasound-guided quadratus lumborum block.

CONCLUSIONS

These results provide robust evidence for the routine use of regional techniques in combination with nonopioid analgesics in perioperative pain management. However, further better quality and larger trials are needed, considering the low confidence levels for certain interventions.

Perioperative analgesia in the elderly

The administration of analgesic drugs in elderly patients should take into account age-related physiological changes, loss of efficiency of homeostatic mechanisms, and pharmacological interactions with chronic therapies. Underestimation of pain in patients with impaired cognition is often linked to difficulties in pain assessment. In the preoperative phase, it is essential to assess the physical status, cognitive reserve, and previous chronic pain conditions to plan effective analgesia. Furthermore, an accurate pharmacological history of the patient must be collected to establish any possible interaction with the whole perioperative analgesic plan. The use of analgesic drugs with different mechanisms of action for pain relief in the intraoperative phase is a crucial step to achieve adequate postoperative pain control in older adults. The combined multimodal and opioid-sparing strategy is strongly recommended to reduce side effects. The use of various adjuvants is also preferable. Moreover, the implementation of non-pharmacological approaches may lead to faster recovery. High-quality postoperative analgesia in older patients can be achieved only with a collaborative interdisciplinary team. The aim of this review is to highlight the perioperative pain management strategies in the elderly with a special focus on intraoperative pharmacological interventions.

A single dose of ketamine relieves fentanyl-induced-hyperalgesia by reducing inflammation initiated by the TLR4/NF-κB pathway in rat spinal cord neurons

A large amount of clinical evidence has revealed that ketamine can relieve fentanyl-induced hyperalgesia. However, the underlying mechanism is still unclear. In the current study, a single dose of ketamine (5 mg/kg or 10 mg/kg), TAK-242 (3 mg/kg), or saline was intraperitoneally injected into rats 15 min before four subcutaneous injections of fentanyl. Results revealed that pre-administration of ketamine alleviated fentanyl-induced hyperalgesia according to hind paw-pressure and paw-withdrawal tests. High-dose ketamine can reverse the expression of toll-like receptor-dimer (d-TLR4), phospho- nuclear factor kappa-B (p-NF-κB, p-p65), cyclooxygenase-2 (COX-2), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) 1 d after fentanyl injection in the spinal cord. Moreover, fentany-linduced-hyperalgesia and changes in the expression of the aforementioned proteins can be attenuated by TAK-242, an inhibitor of TLR4, as well as ketamine. Importantly, TLR4, p-p65, COX-2, and IL-1β were expressed in neurons but not in glial cells in the spinal cord 1 d after fentanyl injection. In conclusion, results suggested that a single dose of ketamine can relieve fentanyl-induced-hyperalgesia via the TLR4/NF-κB pathway in spinal cord neurons.

Impact of Ketamine on Quality of Recovery after Laparoscopic Surgery: A Single-Centre Single-Blinded Trial Using the QoR-15 Questionnaire

Background

The quality of recovery is a cluster of patient-related outcomes that emphasise not only pain but different physical and emotional dimensions. Traditionally, ketamine is used to improve postoperative analgesia and avoid opioid consumption and opioid-related side effects.

Objective

The present study sought to evaluate if intraoperative ketamine administration (as a part of multimodal analgesia) influences the quality of recovery after laparoscopic surgery.

Design

A prospective two-armed, single-blinded trial. Settings. Tertiary single-centre trial between July 2021 and January 2022. Patients. From the 146 patients initially admitted to the study, 127 patients were enrolled, 60 in the ketamine group (group K) and 67 in the control group (group NK). Intervention. Both groups received a rigid intraoperative anaesthesia protocol; furthermore, in group K, 0.5 mg/kg of the ideal body weight of ketamine was administered. Main Outcome Measures. The primary outcome was to evaluate the effect of ketamine administration on the postoperative quality of recovery using the Portuguese version of the Quality of Recovery-15 (QoR-15) Questionnaire 24 h after surgery. The total score and minimal clinically significant difference (MCID) of the QoR-15 were compared. Other variables were also assessed such as the presence of emergence delirium (ED), the Numeric Rating Scale (NRS) for pain, and the presence of postoperative nausea and vomiting (PONV).

Results

A total of 127 patients were allocated to the study groups, 60 in group K and 67 in group NK. Regarding the primary outcome, no differences were found in individual categories (15 items) and in the total score of QoR-15 (p=0.214). Concerning improvement (MCID ≥ 8) or worsening (MCID ≤ 8) in quality of recovery, no difference was found between the groups (24 vs. 32 and 6 vs. 6; p=0.776). Finally, no difference was found in secondary postoperative outcomes including ED (p=0.55), NRS (p=0.401), and PONV (p=0.55).

Conclusion

In this study, the administration of ketamine in laparoscopic surgery had no impact on the quality of recovery 24 h after surgery. This trial is registered with NCT03724019.

Perioperative Low-Dose Ketamine for Postoperative Pain Management in Spine Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

Although low-dose ketamine has been shown to be generally beneficial in terms of pain control in a variety of major surgery, there is no consensus regarding the effectiveness of supplemental ketamine analgesic use exclusively in spine surgery. The objective of this systematic review and meta-analysis of randomized controlled trials (RCTs) was to assess the efficacy and safety of perioperative low-dose ketamine for pain management and analgesic consumption in patients undergoing spine surgery.

Methods

A comprehensive literature search was performed for relevant studies using PubMed, EMBASE, Web of Science, and Cochrane Library. Patients who received perioperative low-dose ketamine were compared to the control group in terms of postoperative pain intensity, opioid consumption, and adverse events. Patients were further categorized by ages and administration times for subgroup analysis.

Results

A total of 30 RCTs comprising 1,865 patients undergoing elective spine surgery were included. Significantly lower pain intensity and less opioid consumption at 12 h, 24 h, and 48 h postoperatively and lower incidence of postoperative nausea and vomiting (PONV) were observed in the ketamine group (all P < 0.05). There was no significant difference of central nervous system (CNS) adverse events between groups. However, different efficacy of low-dose ketamine was detected when patients were categorized by ages and administration times.

Conclusion

Perioperative low-dose ketamine demonstrated analgesic and morphine-sparing effect with no increased adverse events after spine surgery. However, this effect was not significant in pediatric patients. Only postoperative or intraoperative and postoperative administration could prolong the analgesic time up to 48 h postoperatively. Further studies should focus on the optimal protocol of ketamine administration and its effect on old age participants.

Artesunate Reduces Remifentanil-induced Hyperalgesia and Peroxiredoxin-3 Hyperacetylation via Modulating Spinal Metabotropic Glutamate Receptor 5 in Rats

The experimental investigations on the pathogenesis of remifentanil-induced hyperalgesia (RIH) have been primarily conducted, but the effective treatment of RIH remains unclear. Recent reports highlight the necessity of ionotropic glutamate receptors in oxidative damage in spinal nociceptive transduction. Artesunate, the 1st-line anti-malaria drug, has been identified to be valid in removing superoxide in several pathological conditions. This study evaluated whether artesunate inhibits RIH via regulating metabotropic glutamate receptor 5 (mGluR5) and mitochondrial antioxidant enzyme peroxiredoxin-3 in rats. Artesunate was injected intrathecally 10 min before intravenous infusion of remifentanil (1 μg·kg^-1·min^-1 for 60 min) in rats. The antinociception of artesunate was verified by assessment of paw withdrawal mechanical threshold and paw withdrawal thermal latency. Spinal mGluR5 expression and peroxiredoxin-3 hyperacetylation were examined. Also, both the mGluR5 agonist DHPG and antagonist MPEP were utilized to explore the involvement of mGluR5 in the anti-hyperalgesic property of artesunate. Here, we found that artesunate (10 μg and 100 μg but not 1 μg) prevented RIH in a dose-dependent manner. Artesunate reduced remifentanil-related spinal over-expression of mGluR5 gene and protein, and hyperacetylation of peroxiredoxin-3. Intrathecal application of MPEP (10 nmol and 100 nmol but not 1 nmol) inhibited behavioral RIH and peroxiredoxin-3 acetylation. Moreover, hyperalgesia and peroxiredoxin-3 hyperacetylation were attenuated after the combination of artesunate (1 μg) and MPEP (1 nmol). Additionally, artesunate treatment reversed acute pain and peroxiredoxin-3 hyperacetylation following spinal exposure to DHPG. In conclusion, intrathecal injection of artesunate impairs RIH by down-regulating spinal mGluR5 expression and peroxiredoxin-3 hyperacetylation-mediated oxidative stress in rats.

Analgesic and Antidepressant Effects of the Clinical Glutamate Modulators Acetyl-L-Carnitine and Ketamine

Pain and depression are leading causes of disability and of profound social and economic burden. Their impact is aggravated by their chronicity and comorbidity and the insufficient efficacy of current treatments. Morphological and functional metabolism studies link chronic pain and depressive disorders to dysfunctional neuroplastic changes in fronto-limbic brain regions that control emotional responses to painful injuries and stressful events. Glutamate modulators are emerging new therapies targeting dysfunctional brain areas implicated in the generation and maintenance of chronic pain and depression. Here, we report the effects of two clinically approved glutamate modulators: acetyl-L-carnitine (ALCAR) and S, R(±)ketamine (KET). ALCAR is a natural neurotrophic compound currently marketed for the treatment of neuropathies. KET is the prototypical non-competitive antagonist at N-methyl-D-aspartate glutamate receptors and a clinically approved anesthetic. Although they differ in pharmacological profiles, ALCAR and KET both modulate aminergic and glutamatergic neurotransmissions and pain and mood. We assessed in rats the effects of ALCAR and KET on cerebral metabolic rates for glucose (rCMRglc) and assessed clinically the effects of ALCAR in chronic pain and of KET in post-operative pain. ALCAR and KET increased rCMRglc at similar degrees in prefrontal, somatosensory, and cingulate cortices, and KET increased rCMRglc at a different, much larger, degree in limbic and dopaminergic areas. While rCMRglc increases in prefrontal cortical areas have been associated with analgesic and antidepressant effects of ALCAR and KET, the marked metabolic increases KET induces in limbic and dopaminergic areas have been related to its psychotomimetic and abuse properties. In patients with chronic neuropathic pain, ALCAR (1,000 mg/day) yielded to a fast (2 weeks) improvement of mood and then of pain and quality of life. In day-surgery patients, KET improved dischargeability and satisfaction. In obese patients undergoing bariatric surgery, a single, low dose of KET (0.5 mg/kg) at induction of anesthesia determined a very fast (hours) amelioration of post-operative depression and pain and an opioid-sparing effect. These findings indicate that ALCAR and KET, two non-selective glutamate modulators, still offer viable therapeutic options in comorbid pain and depression.

The multiple faces of ketamine in anaesthesia and analgesia

Objective

Ketamine is an anaesthetic agent with a unique dissociative profile and pharmacological effects ranging from the induction and maintenance of anaesthesia to analgesia and sedation, depending on the dose. This article provides information for the clinical use of ketamine in anaesthesia, in both conventional and special circumstances.

Methods

This is a non-systematic review of the literature, through a PubMed search up to February 2021.

Results

With a favourable pharmacokinetic profile, ketamine is used in hospital and prehospital settings for emergency situations. It is suitable for patients with many heart conditions and, unlike other anaesthetics, its potential for cardiorespiratory depression is low. Furthermore, it may be used when venous access is difficult as it may be administered through various routes. Ketamine is the anaesthetic of choice for patients with bronchospasm thanks to its bronchodilatory and anti-inflammatory properties.

Conclusion

With a favourable pharmacokinetic profile, ketamine is used in hospital and prehospital settings for emergency situations and is suitable for patients with many cardiac and respiratory conditions.

The Effect of Ketamine on Acute and Chronic Wound Pain in Patients Undergoing Breast Surgery: A Meta-Analysis and Systematic Review

INTRODUCTION

Perioperative use of ketamine has been discussed widely in many kinds of surgery. The aim of our study was to evaluate the short-term and long-term benefits and safety of ketamine after breast surgery.

METHOD

We performed a quantitative systematic review. We included randomized controlled trials that compared intravenous administration of ketamine to a placebo control group, or compared bupivacaine in combination with ketamine to bupivacaine alone in thoracic paravertebral blocks or pectoral blocks among patients undergoing breast surgery. The primary outcome was postoperative pain intensity. Secondary outcomes included cumulative opioid consumption during the 0- to 24-hour postoperative period, the effect on postmastectomy pain syndrome, the effect on postoperative depression, and the adverse events associated with the use of ketamine.

RESULTS

Thirteen randomized controlled trials with 1,182 patients were included for analysis. Compared with placebo, intravenous ketamine was effective in reducing wound pain intensity during the first 6 hours after surgery (weighted mean difference [WMD] -0.83; 95% confidence interval [CI] -1.65, -0.01; P = 0.048) and during the first 24 hours after surgery (WMD -0.65; 95% CI -0.95, -0.35; P < 0.001), and in decreasing opioid consumption (WMD -4.14; 95% CI -8.00, -0.29; P = 0.035) during the first 24 hours after surgery, without increasing the risks for gastrointestinal and central nervous system adverse events. Adding ketamine to bupivacaine in thoracic paravertebral blocks was also effective in reducing postoperative wound pain during the first 6 hours after surgery (WMD -0.59; 95% CI, -1.06, -0.12; P = 0.014) and during the first 24 hours after surgery (WMD -0.90; 95% CI -1.27, -0.53; P < 0.001), and in decreasing opioid consumption (WMD - 4.59; 95% CI -5.76, -3.42; P < 0.001) during the first 24 hours after surgery. Perioperative use of ketamine was associated with improved postoperative depression symptoms (standardized mean difference -0.80; 95% CI - 1.34, -0.27; P = 0.003) and less incidence of postmastectomy pain syndrome (relative risk 0.79; 95% CI 0.63, 0.99; P = 0.043).

CONCLUSION

Ketamine is an effective and safe multimodal analgesic in patients undergoing breast surgery, administered both intravenously and when added to bupivacaine in paravertebral blocks. In addition, ketamine showed a long-term benefit for preventing postoperative depression and postmastectomy pain syndrome.

Effects of virtual reality on relieving postoperative pain in surgical patients: A systematic review and meta-analysis

BACKGROUND

Postoperative pain is a prevalent problem leading to many adverse outcomes in surgical patients. Virtual reality (VR) is an emerging non-pharmacological method of postoperative pain relief, but the effects of it are not clear. This review aimed to explore the effects of VR on relieving postoperative pain.

METHODS

Studies published up to November 2019 were identified by searching the PubMed (Medline), Embase, Web of Science, and other databases. Meta-analyses were conducted to compare VR and usual care for relieving postoperative pain. Subgroup analyses and sensitivity analyses were performed to explain the heterogeneity.

RESULTS

Overall, 8 randomized control trials (RCTs) enrolling 723 participants were included. Our results demonstrated that the patients receiving the VR intervention had lower postoperative pain scores than those receiving the usual care (mean difference [MD] -0.64; 95% CI -1.05 to -0.22; P = 0.002). One subgroup analysis revealed that VR could relieve postoperative pain both in minor surgery (MD -1.48; 95% CI -2.02 to -0.95; P < 0.0001) and major surgery (MD -0.32; 95% CI -0.53 to -0.11; P < 0.03). Another subgroup analysis demonstrated a significant reduction in postoperative pain among patients receiving VR during the intraoperative (MD -1.51; 95% CI -2.04 to -0.97; P < 0.00001) and the postoperative periods (MD -0.50; 95% CI -0.76 to -0.24; P = 0.002). However, there was no significant postoperative pain relief when receiving VR during the preoperative period. Additionally, significant improvements in postoperative satisfaction were reported in two studies. However, another two studies included found that VR could not affect physiological parameters related to pain.

CONCLUSIONS

Applying VR can relieve postoperative pain effectively. The type of surgery and timing of using VR are the main sources of heterogeneity. More rigorous studies about the relationship between VR and postoperative pain relief will be needed.

Comparison of Ketamine and Tramadol in Management of Acute Pain; a Systematic Review

INTRODUCTION

Management of pain is an important part of care in the emergency department (ED). Tramadol and Ketamine have both been introduced as alternatives to opioids in the ED and post-operative setting. In this study, we conducted a systematic review of available literature to compare the analgesic efficacy, and side effect profile of these two medications in management of severe acute pain.

METHODS

This is a systematic review based on the PRISMA protocol. In this study, peer-reviewed papers published by March 3, 2020, which compared analgesic effects of tramadol and ketamine in management of acute pain were included.

RESULT

The initial search of online databases identified 2826 non-duplicate records. Finally, three papers available in full text were analyzed for study quality. The results show that ketamine has consistently been shown to be superior to tramadol for pain control and causes fewer significant side effects.

CONCLUSION

Results of this review show that low-dose ketamine is more effective than tramadol in pain control, while causing fewer side effects.