Single dose oral analgesics for acute postoperative pain in adults

Immediate Efficacy of Contralateral Acupuncture on SI3 Combined with Active Exercise for Acute Lumbar Sprains: Protocol for a Randomized Controlled Trial

Purpose

Acute lumbar sprain (ALS) is a common clinical disease characterized by persistent intolerable low back pain and limitation of movement, and quick pain relief and restoration of mobility in a short time are the main needs of patients when they visit the clinic. This study aims to evaluate the immediate efficacy of contralateral acupuncture (CAT) on SI3 combined with active exercise in treating ALS.

Methods and Analysis

This study is a randomized controlled trial which will recruit 118 eligible participants aged 18 to 55 years with ALS at the Second Affiliated Hospital of Yunnan University of Chinese Medicine between March 2024 and December 2026. Participants will be randomly assigned to the acupuncture group or the sham-acupuncture group in a 1:1 ratio. The acupuncture group will receive a 10-minute acupuncture treatment combined with active exercise, while the sham-acupuncture group will receive a 10-minute sham acupuncture treatment combined with active exercise. Randomization will use a computer-generated sequence with allocation concealed in opaque envelopes. The primary outcome will be the pain visual analogue scale (VAS) scores after 10 minutes of treatment. Secondary outcomes will include the pain VAS scores at other time points (2, 4, 6, and 8 minutes post-treatment), the lumbar range of motion (ROM) scores at various time points, blinded assessment, the treatment effect expectancy scale, and the rescue analgesia rate. The analysis will follow the intention-to-treat principle. The primary outcome will be analyzed using ANCOVA, and secondary outcomes with repeated measures ANOVA. The rescue analgesia rate will be assessed using either the χ2 test or Fisher's exact test.

Discussion

This study is the first randomized controlled trial to assess the immediate efficacy of CAT in combination with active exercise for ALS. This study will provide a simple, rapid, and effective treatment for the clinical management of ALS.

Acute Postoperative Pain Due to Dental Extraction in the Adult Population: A Systematic Review and Network Meta-analysis

This study compares the effectiveness of pharmacological treatments to develop guidelines for the management of acute pain after tooth extraction. We searched Medline, EMBASE, CENTRAL, and US Clinical Trials registry on November 21, 2020. We included randomized clinical trials (RCTs) of participants undergoing dental extractions comparing 10 interventions, including acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, and combinations to placebo. After duplicate screening and data abstraction, we conducted a frequentist network meta-analysis for each outcome at 6 h (i.e., pain relief, total pain relief [TOTPAR], summed pain intensity difference [SPID], global efficacy rating, rescue analgesia, and adverse effects). We assessed the risk of bias using a modified Cochrane RoB 2.0 tool and the certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation approach. We implemented the analyses in RStudio version 3.5.3 and classified interventions from most to least beneficial or harmful. We included 82 RCTs. Fifty-six RCTs enrolling 9,095 participants found moderate- and high-certainty evidence that ibuprofen 200 to 400 mg plus acetaminophen 500 to 1,000 mg (mean difference compared to placebo [MDp], 1.68; 95% confidence interval [CI], 1.06-2.31), acetaminophen 650 mg plus oxycodone 10 mg (MDp, 1.19; 95% CI, 0.85-1.54), ibuprofen 400 mg (MDp, 1.31; 95% CI, 1.17-1.45), and naproxen 400-440 mg (MDp, 1.44; 95% CI, 1.07-1.80) were most effective for pain relief on a 0 to 4 scale. Oxycodone 5 mg, codeine 60 mg, and tramadol 37.5 mg plus acetaminophen 325 mg were no better than placebo. The results for TOTPAR, SPID, global efficacy rating, and rescue analgesia were similar. Based on low- and very low-certainty evidence, most interventions were classified as no more harmful than placebo for most adverse effects. Based on moderate- and high-certainty evidence, NSAIDs with or without acetaminophen result in better pain-related outcomes than opioids with or without acetaminophen (except acetaminophen 650 mg plus oxycodone 10 mg) or placebo.

NSAID chronotherapy after impacted third molar extraction: a randomized controlled trial

OBJECTIVES

Postoperative pain management impacts patients' quality of life and morbidity. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen are widely used for this following a 3-doses-per-day regime. However, pain and inflammation follow a circadian rhythm, and animal models assessing the scheduling of NSAID administration (e.g., chronotherapy) have shown that while their use during the active phase of the day enhances postoperative recovery, their administration during the resting phase could have detrimental effects. This observation has led us to hypothesize that night administration of NSAID might be unnecessary in post-surgical scenarios. Therefore, a randomized clinical trial was conducted to test this hypothesis in surgical third molar extractions.

MATERIALS AND METHODS

Seventy (18-35 years) healthy participants requiring surgical removal of impacted lower third molars were recruited and randomized into a double-blind placebo-controlled study. For three days postoperatively, the treatment group (n = 33) received ibuprofen (400 mg) at 8 AM, 1 PM, and a placebo at 8 PM, while the control group (n = 37) received ibuprofen (400 mg) at 8 AM, 1 PM, and 8 PM. Pain severity was assessed by visual analog scale (VAS) and healing indicators including facial swelling, mouth opening, and C-reactive protein blood levels were also measured.

RESULTS

Pain VAS measures showed a circadian variation peaking at night. Also, no significant differences were observed between the two groups of the study in terms of postoperative pain scores (estimate: 0.50, 95% CI = [- 0.38, 1.39]) or any other healing indicator.

CONCLUSIONS

Postoperative pain follows a circadian rhythm. Moreover, night administration of ibuprofen might not provide any significant benefits in terms of pain management and control of inflammation, and two doses during the day only could be sufficient for pain management after surgical interventions.

KNOWLEDGE TRANSFER STATEMENT

Even though this study cannot rule out the possibility that a reduced regime is different than a standard regime, nocturnal doses of ibuprofen seem to have no clinical significance in the short term, and the results of this study provide evidence in favor of reducing ibuprofen administration from three doses to two doses only after third molar surgery.

Pain Reduction With an Immersive Digital Therapeutic Tool in Women Living With Endometriosis-Related Pelvic Pain: Randomized Controlled Trial

BACKGROUND

Chronic pelvic pain is a common and disabling condition in women living with endometriosis. Pharmacological and surgical treatments are not always effective at controlling pain and present important restrictions. Digital therapeutics (DTx) are emerging as major nonpharmacological alternatives that aim to extend the analgesic therapeutic arsenal of patients.

OBJECTIVE

In this randomized controlled trial (RCT), we aimed to measure the immediate and 4-hour persisting effects of a single use 20-minute DTx (Endocare) on pain in women experiencing pelvic pain due to endometriosis.

METHODS

A total of 45 women with endometriosis participated in a randomized controlled study comparing the analgesic effect of a single use of a virtual reality digital treatment named Endocare (n=23, 51%) to a 2D digital control (n=22, 49%). Perceived pain and pain relief were measured before the treatment and 15, 30, 45, 60, and 240 minutes after the end of the treatment.

RESULTS

The clustered posttreatment pain was significantly reduced compared to the pretreatment for both Endocare and the control group (all P<.01). Endocare was significantly more effective than the control group (all P<.01). Endocare decreased the mean pain intensity from 6.0 (SD 1.31) before the treatment to 4.5 (SD 1.71) posttreatment, while the control only decreased it from 5.7 (SD 1.36) to 5.0 (SD 1.43). When comparing each posttreatment measures to the pretest, Endocare significantly reduced pain perception for all points in time up to 4 hours posttreatment. The differences did not reached significance for the control group. Moreover, Endocare was significantly superior to the control group 15, 30, and 45 minutes after the treatment (all P<.001). The mean perceived pain relief was significantly higher for Endocare at 28% (SD 2%) compared to the control, which was 15% (SD 1%) for all the posttreatment measurements (all P>.05).

CONCLUSIONS

Our study aimed to test the effects of a single use of a DTx treatment on reported pain at different time points in women diagnosed with endometriosis experiencing moderate-to-severe pelvic pain. Importantly, our results support that Endocare, a virtual reality immersive treatment, significantly reduce pain perception compared to a digital control in women living with endometriosis. Interestingly, we are the first to notice that the effect persisted up to 4 hours posttreatment.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04650516; https://tinyurl.com/2a2eu9wv.

Patients receiving knee arthroplasty with pre-existing long-term aspirin use suffer lower risk of perioperative complications but feel more postoperative pain

BACKGROUND

Aspirin has gained increasing use-popularity on account of its multiple benefits. The present study aimed to investigate how a pre-existing long-term aspirin use (L-AU) would affect perioperative complications and postoperative pain in primary total knee arthroplasty (TKA) patients.

METHODS

Utilizing the National Inpatient Sample (NIS) database, primary TKAs were divided into L-AU and non-L-AU cohorts. Propensity score matching (PSM) was performed to match the demographics and comorbidities characteristics. Chi-square test and logistic regression analysis were calculated for the risk analysis of perioperative complications and postoperative pain.

RESULTS

The popularity of L-AU in primary TKA patients had significantly increased from 1.5% (2005) to 10.5% (2014) in the U.S. Pre-existing L-AU was associated with decreased risks of most perioperative complications (any complication, adjusted odds ratio [aOR]: 0.920), in-hospital mortality (aOR: 0.367), and shortened hospitalization stay (LOS) (aOR: 0.647), etc. However, L-AU was recognized as a risk factor of acute postoperative pain (aOR: 1.466) and slightly higher total cost (aOR: 1.047).

CONCLUSIONS

For the first time in the present study, it is found that pre-existing long-term aspirin use is benefic in reducing perioperative complication risk. According to this finding, future research might determine the optimal pre-operational taking time and dose of aspirin use. Consequently, orthopedic surgeons and healthcare providers could provide this valuable advice to specific patients prior to a planned arthroplasty and subsequently gain feasible clinical benefits.

ANALGESIC EFFICACY OF TRAMADOL/DEXKETOPROFEN VS IBUPROFEN AFTER IMPACTED LOWER THIRD MOLAR EXTRACTION: A RANDOMIZED CONTROLLED CLINICAL TRIAL

OBJECTIVE

Impacted third molar extraction is associated with acute moderate-to-severe pain for up to 48 hours post-surgery. This trial was designed to compare the analgesic effectiveness, swelling, and adverse events after impacted third molar surgery following multimodal therapy with 75 mg tramadol hydrochloride plus 25 mg dexketoprofen or monotherapy with 400 mg ibuprofen.

METHODS

Seventy-two patients were randomly assigned to receiving ibuprofen (n = 36) or tramadol-dexketoprofen (n = 36). Postoperative pain intensity and swelling were measured using a visual analog scale (VAS); pain relief experienced was reported using a 4-point verbal rating scale; the rescue medication requirement, adverse effects, and global impression of the medication were recorded.

RESULTS

No statistically significant between-group difference in pain intensity was observed at any time point; however, pain relief was significantly higher in the tramadol-dexketoprofen treated-group at 6 and 36 hours. Self-reported verbal rating scale assessments showed significantly lower swelling in the tramadol-dexketoprofen group at 24 hours post-surgery but not at 48 or 72 hours, and VAS-swelling scores showed no significant between-group difference. The frequency of postoperative nausea and dizziness was significantly higher in the tramadol-dexketoprofen group.

CONCLUSIONS

Multimodal therapy proved more effective to manage moderate-severe pain after impacted third molar surgery in comparison to monotherapy. However, the improvement in relief must be balanced against the increased risk of adverse effects when considering this multimodal approach.

Non-steroidal anti-inflammatory drugs and bone healing in animal models-a systematic review and meta-analysis

BACKGROUND

Non-steroidal anti-inflammatory drugs (NSAID) have excellent anti-inflammatory and analgesic properties and are extensively used to treat post-traumatic or surgical musculoskeletal pain. Although an extensive literature exists on the administration of NSAID on animal bone healing, no systematic review and meta-analysis of animal studies that investigate the effect of NSAID administration on bone fracture healing. Objective of this study is to conduct a systematic review and meta-analysis to estimate the effect of NSAIDs administration on bone healing biomechanical and histomorphometric measurements in different animal models after bone fracture surgery.

METHODS

We performed a systematic review and meta-analysis of animal studies to estimate the effect of NSAID administration after bone fracture on healing outcomes. We searched eight databases without limiting the search to starting date up to 1 February 2021 for articles on fractured bone healing in animal models in which NSAID were administered.

RESULTS

Out of 6732 articles screened, 47 were included and 3 common bone healing outcomes were analysed: biomechanical properties (maximum force to break, stiffness, and work-to-failure), micro-computed tomography (μ-CT), and histomorphometric measurements. The studies were generally of low-quality scores because crucial information, especially concerning randomization, blinding, and allocation concealment, was poorly reported. Our results show that the negative effects of NSAID after bone fracture on certain biomechanical properties of the healing bones was not statistically significant in mice compared with other animals, in females compared with males, and in younger compared with older animals.

CONCLUSION

The findings demonstrated that NSAIDs administration decreased the biomechanical properties of healing bones after fracture surgery in comparison to the control group. Moreover, different effect on certain outcomes was detected among different sites, sex of the animals, and the time of assessment.

TRIAL REGISTRATION

Protocol published and registered in SYstematic Review Center for Laboratory animal Experimentation (SYRCLE) in 2017, https://www.radboudumc.nl/getmedia/757ec408-7a9e-4635-8233-ae951effea54/Non-Steroidal-Anti-inflammatory-Drugs-and-bone-healing-in-animal-Models-Systematic-Review-and-Meta-Analysis.aspx.

Pain in Oral and Maxillofacial Surgery and Implant Dentistry: Types and Management

Over the years, the pain has been defined numerous times in several ways. In oral and maxillofacial surgery, the occurrence of pain, especially postoperatively, is anticipated. Pain arises as a combination of various processes after tissue damage. Distinct pain experiences in oral surgery were depicted in several previous studies, adding knowledge to the field. The management of these encounters has been suggested over time, improving treatment approaches in the clinical setting. This review aims to understand the pain and its types and intervention in the field of oral and maxillofacial surgery.

Post-operative pain management in dental implant surgery: a systematic review and meta-analysis of randomized clinical trials

PURPOSE

To evaluate the clinical efficacy of various analgesic medications in mitigating orofacial pain following dental implant surgery.

MATERIALS AND METHODS

A systematic search was conducted to identify randomized controlled clinical trials (RCTs). The primary outcomes examined were post-operative pain (POP) and consumption of rescue analgesics following implant placement; secondary outcomes included adverse effects, post-operative inflammation, infection, swelling, bleeding, patient satisfaction, and quality of life. Random effects meta-analysis was conducted for risk ratios of dichotomous data.

RESULTS

Nine RCTs fulfilled the eligibility criteria. Individual studies and meta-analysis of two studies indicated that nonsteroidal anti-inflammatory drugs (NSAIDs) significantly reduced POP and consumption of rescue analgesics after dental implant placement compared to placebo. Transdermal administration of NSAIDs may be superior to the oral route as it was similarly effective for POP control and resulted in fewer side effects. Glucocorticoids administered as primary analgesics or NSAID adjuvants resulted in comparable pain sensation compared to NSAIDs alone. Caffeine-containing analgesics were reported as acceptable and effective for the treatment of POP and swelling when compared to codeine adjuvants. With regard to analgesic dosing schedules, pain modulation may be most critical during the first 72 h following dental implant placement. Risk of bias assessment indicated an overall low risk of bias across the included trials.

CONCLUSION

Within the limitations of this review, POP following implant surgery may be effectively treated with the short-term use of analgesic medications. However, given the heterogeneity in the available RCTs, there is insufficient evidence to recommend an analgesic regimen following dental implant surgery.

CLINICAL RELEVANCE

Short-term use of analgesic medications may be sufficient for post-operative pain management in dental implant surgery. Ultimately, the clinician's analgesic prescription should be directed by a patient's medical history, in order to increase the success of pain management in a short period of time and decrease potential adverse effects.

TRIAL REGISTRATION

CRD42018099324.

The Efficacy of Acetominophen for Total Laparoscopic Hysterectomy

OBJECTIVE

Despite limited data, acetaminophen, along with other agents, is commonly included in enhanced recovery after surgery (ERAS) protocols following laparoscopic hysterectomy. We aimed to systematically review the efficacy of acetaminophen on the management of postoperative pain after laparoscopic hysterectomy.

METHODS

We searched PubMed, SCOPUS, Web of Science, and Cochrane Library databases for relevant clinical trials investigating the role of acetaminophen in the management of pain after laparoscopic hysterectomy. We performed the risk of bias according to Cochrane's risk of bias tool. We performed the analysis of homogeneous data under the fixed-effects model during the analysis of heterogeneous data under the random-effects model. The primary outcome was the assessment of pain score after 2, 6, 12, and 24 h.

RESULTS

A total of 495 patients in 13 trials were included in our meta-analysis. Acetaminophen was not superior at reducing postoperative pain scores. Further analysis at progressive temporal points revealed no further significance; effect size at after 2 h (SMD = -0.020, 95% CI (-0.216; 0.176)), 6 h (SMD = -0.115, 95% CI (-0.312; 0.083)), 12 h (SMD = -0.126, 95% CI (-0.277; 0.025)), or 24 h (SMD = 0.063, 95% CI (-0.065; 0.191)). Pooled analysis was heterogeneous (P < 0.1); therefore, we conducted a sensitivity analysis yielding homogeneous results. The drug did not reduce opioid need (MD = -0.16, 95% CI (-2.39, 2.06), P = 0.89).

CONCLUSION

We conclude that acetaminophen is not beneficial for reducing pain after laparoscopic hysterectomy. Other alternatives have better results. Caution should be given to the inclusion of acetaminophen in ERAS protocols designed for laparoscopic hysterectomy, especially as a single agent or to reduce opioid consumption.

Dexibuprofen in the Practice of a Family Doctor

Pain is an unpleasant sensory and emotional sensation associated with tissue damage or described in terms of such damage. Pain of different localization is one of the most common symptoms in modern clinical practice and one of the most common reasons for seeking medical care at the outpatient stage. One of the most promising and effective pathogenetic means of protection of peripheral pain receptors (nociceptors) are nonsteroidal anti-inflammatory drugs (NSAIDs). Every day, more than 30 million people in the world take NSAIDs, more than 300 million a year, and only a third of them take nonsteroidal anti-inflammatory drugs as prescribed by a doctor. However, patients taking various drugs today are considered as possible etiological and provoking factors in the development of a number of diseases of various organs and systems. All this determines the importance of selecting the optimal drug from the group of nonsteroidal anti-inflammatory drugs both from the standpoint of effectiveness and from the standpoint of safety in real clinical practice and including at the outpatient stage of providing medical care to the patient. One of the latest developments in this direction is dexibuprofen, the right-handed active isomer of ibuprofen, which according to numerous studies can be used as a symptomatic therapy of pain of mild to moderate intensity of various origins: toothache, back pain, joints, muscles, rheumatic pain, dysmenorrhea, and feel free to recommend it to a wide range of patients, as it has the optimal combination of efficacy and safety profile.

Properties of Thermal Analgesia in a Human Chronic Low Back Pain Model

Purpose

For years, heat has been used for comfort and analgesia is recommended as a first-line therapy in many clinical guidelines. Yet, there are questions that remain about the actual effectiveness of heat for a condition as common as chronic low back pain, and factors such as time of onset, optimal temperature, and duration of effect.

Materials and Methods

A randomized double-blinded controlled trial was designed to compare the analgesic response to heat delivered via pulses at 45°C (experimental group, N=49) to steady heat at 37°C (control group, N=51) in subjects with longstanding low back pain. Treatment lasted 30 minutes with follow-up out to four hours. The hypothesis was that the experimental group would experience a higher degree of analgesia compared to the control group. Time of onset and duration of effect were also measured.

Results

Both groups were similar in average duration of pain (10.3 years). The primary outcome measure was pain reduction at 30 minutes after the end of treatment, using a 10-points numeric pain scale. Reduction in pain was greater for the experimental group than the control group (difference in mean reduction = 0.72, 95% CI 0.15–1.29, p = 0.014). Statistically significant differences in pain levels were observed from the first measure at 5 minutes of treatment through 120 minutes after completion of treatment. Reduction in pain associated movement was greater in the active heat group than the placebo group (p = 0.04).

Conclusion

High-level pulsed heat (45°C) produced significantly more analgesia as compared to steady heat at 37°C at the primary end point and for an additional 2 hours after treatment. The onset of analgesia was rapid, <5 minutes of treatment. The results of this trial provide insight into the mechanisms and properties of thermal analgesia that are not well understood in a chronic low back pain model.

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New Approaches to Pain Management

Opioid addiction has reached epidemic proportions in the United States and it is thought that the problem started with the prescription for legal pain medications by health care professionals, particularly for treating patients who had undergone surgery. To reduce the reliance on opioids in dental pain management, increase use of nonsteroidal anti-inflammatory drugs (NSAIDs) and other adjunctive techniques have emerged. The use of NSAIDs, transdermal and transmucosal patches are presented. Understanding the rational for these different approaches requires a basic knowledge of the molecular biology of dental pain.

Loxoprofen Sodium Versus Diclofenac Potassium for Post-Dental Extraction Pain Relief: A Randomized, Triple-Blind, Clinical Trial

One of the most common post-operative complications of tooth extraction is pain. Oral analgesics, namely loxoprofen sodium and diclofenac potassium, are often prescribed; however, the efficacy of these drugs irrespective of gender and type of extraction has not been tested. Therefore, this study aimed to compare the efficacy of these two drugs in post-dental extraction pain relief among male and female patients in cases of simple and surgical tooth extraction. A single-center, triple-blind, randomized clinical trial was conducted among 100 male and female patients who underwent tooth extraction at Taibah University Dental College and Hospital in Al-Madinah, Saudi Arabia. The patients reported their pain post-operatively after 6 hours and every 12 h for 3 days using the Verbal Descriptor Scale (e.g., "no pain", "mild pain"). Descriptive statistics and chi-square tests were run to analyze the data. An equal number of patients received either the drug loxoprofen sodium or diclofenac potassium and completed the study follow-up. Patients allocated to the diclofenac potassium drug group after 36 h were statistically significantly in their reporting of "no pain" and "mild pain" compared to patients allocated to the loxoprofen sodium group (86% vs. 66%, respectively; p = 0.019), irrespective of gender or type of tooth extraction. However, both groups demonstrated comparable (p > 0.05) post-operative pain relief over the other aforementioned allocated time intervals. In conclusion, the diclofenac potassium group had slightly better control over post-operative pain than the group receiving loxoprofen sodium.

gem-Difluorobisarylic derivatives: design, synthesis and anti-inflammatory effect

Introduction

New fluorinated diaryl ethers and bisarylic ketones were designed and evaluated for their anti-inflammatory effects in primary macrophages.

Methods

The synthesis of the designed molecules started from easily accessible and versatile gem-difluoro propargylic derivatives. The desired aromatic systems were obtained using Diels-Alder/aromatization sequences and this was followed by Pd-catalyzed coupling reactions and, when required, final functionalization steps. Both direct inhibitory effects on cyclooxygenase-1 or -2 activities, protein expression of cyclooxygenase-2 and nitric oxide synthase-II and the production of prostaglandin E₂, the pro-inflammatory nitric oxide and interleukin-6 were evaluated in primary murine bone marrow-derived macrophages in response to lipopolysaccharide. Docking of the designed molecules in cyclooxygenase-1 or -2 was performed.

Results

Only fluorinated compounds exerted anti-inflammatory activities by lowering the secretion of interleukin-6, nitric oxide, and prostaglandin E₂, and decreasing the protein expression of inducible nitric oxide synthase and cyclooxygenase-2 in mouse primary macrophages exposed to lipopolysaccharide, as well as cyclooxygenase activity for some inhibitors with different efficiencies depending on the R-groups. Docking observation suggested an inhibitory role of cyclooxygenase-1 or -2 for compounds A3, A4 and A5 in addition to their capacity to inhibit nitrite, interleukin-6, and nitric oxide synthase-II and cyclooxygenase-2 expression.

Conclusion

The new fluorinated diaryl ethers and bisarylic ketones have anti-inflammatory effects in macrophages. These fluorinated compounds have improved potential anti-inflammatory properties due to the fluorine residues in the bioactive molecules.

Nonsteroidal anti-inflammatory drugs and acetaminophen ameliorate muscular mechanical hyperalgesia developed after lengthening contractions via cyclooxygenase-2 independent mechanisms in rats

Nonsteroidal anti-inflammatory drugs and acetaminophen are cyclooxygenase inhibitors commonly used as symptomatic medicines for myofascial pain syndrome. Using the selective inhibitors celecoxib and zaltoprofen, cyclooxygenase-2 has been shown to be involved in the initiation, but not the maintenance, of muscular mechanical hyperalgesia induced by lengthening contractions, which serves as a useful model for the study of myofascial pain syndrome. The effect of other cyclooxygenase-2 inhibitors, such as acetylsalicylic acid, ibuprofen, loxoprofen sodium, and acetaminophen, on muscular mechanical hyperalgesia during maintenance has not been studied. Here, we examined the analgesic effects of the nonsteroidal anti-inflammatory drugs and acetaminophen on the model. Consistent with previous studies, mechanical withdrawal threshold of the muscle was significantly decreased and reached its lowest level 24 h after lengthening contractions. Celecoxib had no effect on muscular mechanical hyperalgesia, when orally administered 24 h after lengthening contractions. In contrast, acetylsalicylic acid, ibuprofen, loxoprofen sodium, and acetaminophen increased the withdrawal threshold, which had decreased by lengthening contractions, in a dose-dependent manner. These results demonstrate the analgesic actions of nonsteroidal anti-inflammatory drugs and acetaminophen in the maintenance process of lengthening contraction-induced muscular mechanical hyperalgesia, which may occur through cyclooxygenase-2 independent mechanisms.

Characterisation and optimisation of diclofenac sodium orodispersible thin film formulation

Oral Thin Film (OTF) is a newly emerging drug delivery system which has many benefits for patients. Although there has been some formulation of OTF products, these have mainly been as confectionary or dental health products. The most significant benefit of this dosage format will only be realised once more pharmaceutical products become available. Within this paper, OTF strips containing Diclofenac Sodium were prepared using the solvent casting method and then characterised to ensure the method could conform to acceptable levels of uniformity, the mean (SD) diclofenac sodium content was 25.43 (1.39) mg, range 22.84-27.44 mg. Bioburden was tested against coliforms, yeasts and moulds and all results were confirmed to be <10 CFU/g, also similar dissolution profile when compared to a commercial product to ensure biowaiver. An acceptable level of uniformity of mass was produced. K-F titration was employed to reduce the water content of the strips and it was found to be acceptable, this represented a level of water which would not be viable for microbial growth. The technique employed here in the production of OTF resulted in high quality products and amenability to being up scaled. Furthermore, the characterisation method was also sufficient to assess the quality of the products and may be used for future analysis of OTF pharmaceuticals.

Analgesic Therapy in Dentistry: From a Letter to the Editor to an Evidence-Base Review

It has been known for centuries that opioids are highly addictive when consumed for prolonged periods of time. Pharmacologic tolerance to the efficacy of opioid analgesic results in a need for increased dosing and drug dependence. One must question the empirical sources of evidence that justified the belief that prescription opioids were safe and effective for treating acute and chronic pain. Progress in developing and applying evidence-based analgesic therapies for acute inflammatory pain is presented.

Single-dose intravenous diclofenac for acute postoperative pain in adults

BACKGROUND

Postoperative administration of non-steroidal anti-inflammatory drugs (NSAIDs) reduces patient opioid requirements and, in turn, reduces the incidence and severity of opioid-induced adverse events (AEs).

OBJECTIVES

To assess the analgesic efficacy and adverse effects of single-dose intravenous diclofenac, compared with placebo or an active comparator, for moderate to severe postoperative pain in adults.

SEARCH METHODS

We searched the following databases without language restrictions: the Cochrane Central Register of Controlled Trials (Cochrane Register of Studies Online), MEDLINE, and Embase on 22 May 2018. We checked clinical trials registers and reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

We included randomized trials that compared a single postoperative dose of intravenous diclofenac with placebo or another active treatment, for treating acute postoperative pain in adults following any surgery.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two review authors independently considered trials for review inclusion, assessed risk of bias, and extracted data.Our primary outcome was the number of participants in each arm achieving at least 50% pain relief over a four- and six-hour period.Our secondary outcomes were time to, and number of participants using rescue medication; withdrawals due to lack of efficacy, AEs, and for any cause; and number of participants experiencing any AE, serious AEs (SAEs), and NSAID-related AEs. We performed a post hoc analysis of opioid-related AEs, to enable indirect comparisons with other analyses of postoperative analgesics.For subgroup analysis, we planned to analyze different doses and formulations of parenteral diclofenac separately.We assessed the overall quality of the evidence for each outcome using GRADE and created two 'Summary of findings' tables.

MAIN RESULTS

We included eight studies, involving 1756 participants undergoing various surgeries (dental, mixed minor, abdominal, and orthopedic), with 20 to 175 participants receiving intravenous diclofenac in each study. Mean study population ages ranged from 24.5 years to 54.5 years. Intravenous diclofenac doses varied among and within studies, ranging from 3.75 mg to 75 mg. Five studies assessed newer formulations of parenteral diclofenac that could be administered as an undiluted intravenous bolus. Most studies had an unclear risk of bias for several domains and a high risk of bias due to small sample size. The overall quality of evidence for each outcome was generally low for reasons including unclear risk of bias in studies, imprecision, and low event numbers.Primary outcomeThree studies (277 participants) produced a number needed to treat for an additional beneficial outcome (NNTB) for at least 50% of maximum pain relief versus placebo of 2.4 (95% confidence interval (CI) 1.9 to 3.1) over four hours (low-quality evidence). Four studies (436 participants) produced an NNTB of 3.8 versus placebo (95% CI 2.9 to 5.9) over six hours (low-quality evidence). No studies provided data for the comparison of intravenous diclofenac with another NSAID over four hours. At six hours there was no difference between intravenous diclofenac and another NSAID (low-quality evidence).Secondary outcomesFor secondary efficacy outcomes, intravenous diclofenac was generally superior to placebo and similar to other NSAIDs.For time to rescue medication, comparison of intravenous diclofenac versus placebo demonstrated a median of 226 minutes for diclofenac versus 80 minutes for placebo (5 studies, 542 participants, low-quality evidence). There were insufficient data for pooled analysis for comparisons of diclofenac with another NSAID (very low-quality evidence).For the number of participants using rescue medication, two studies (235 participants) compared diclofenac with placebo. The number needed to treat to prevent one additional harmful event (NNTp) (here, the need for rescue medication) compared with placebo was 3.0 (2.2 to 4.5, low-quality evidence). The comparison of diclofenac with another NSAID included only one study (98 participants). The NNTp was 4.5 (2.5 to 33) for ketorolac versus diclofenac (very low-quality evidence).The numbers of participants withdrawing were generally low and inconsistently reported (very low-quality evidence). Participant withdrawals were: 6% (8/140) diclofenac versus 5% (7/128) placebo, and 9% (8/87) diclofenac versus 7% (6/82) another NSAID for lack of efficacy; 2% (4/211) diclofenac versus 0% (0/198) placebo, and 3% (4/138) diclofenac versus 2% (2/129) another NSAID due to AEs; and 11% (21/191) diclofenac versus 17% (30/179) placebo, and 18% (21/118) diclofenac versus 15% (17/111) another NSAID for any cause.Overall adverse event rates were similar between intravenous diclofenac and placebo (71% in both groups, 2 studies, 296 participants) and between intravenous diclofenac and another NSAID (55% and 58%, respectively, 2 studies, 265 participants) (low-quality evidence for both comparisons). Serious and specific AEs were rare, preventing meta-analysis.There were sufficient data for a dose-effect analysis for our primary outcome for only one alternative dose, 18.75 mg. Analysis of the highest dose employed in each study demonstrated a relative benefit compared with placebo of 1.9 (1.4 to 2.4), whereas for the group receiving 18.75 mg, the relative benefit versus placebo was 1.6 (1.2 to 2.1, 2 studies). Compared to another NSAID, the high-dose analysis demonstrated a relative benefit of 0.9 (0.8 to 1.1), for the group receiving 18.75 mg, the relative benefit was 0.78 (0.65 to 0.93). For direct comparison of high dose versus 18.75 mg, the proportion of participants with at least 50% pain relief was 66% (90/137) for the high-dose arm versus 57% (77/135) in the low-dose arm. There were insufficient data for subgroup meta-analysis of different diclofenac formulations.

AUTHORS' CONCLUSIONS

The amount and quality of evidence for the use of intravenous diclofenac as a treatment for postoperative pain is low. The available evidence indicates that postoperative intravenous diclofenac administration offers good pain relief for the majority of patients, but further research may impact this estimate. Adverse events appear to occur at a similar rate to other NSAIDs. Insufficient information is available to assess whether intravenous diclofenac has a different rate of bleeding, renal dysfunction, or cardiovascular events versus other NSAIDs. There was insufficient information to evaluate the efficacy and safety of newer versus traditional formulations of intravenous diclofenac. There was a lack of studies in major and cardiovascular surgeries and in elderly populations, which may be at increased risk for adverse events.

Preemptive Effect of Dexamethasone in Third-Molar Surgery: A Meta-Analysis

The aim of the present study was to assess the effectiveness of preemptive dexamethasone in surgery of the lower third molars and to compare it with other oral anti-inflammatories. An electronic search was conducted for preemptive effects related to lower third-molar surgery in 3 separate databases. The variables pain, swelling, and trismus were assessed. Meta-analysis was used to calculate the pooled effect measures for mean and standard deviation values (95% confidence interval [CI]). Seven split-mouth clinical trials were selected. Two studies were included in the meta-analysis. Three studies showed a low risk of bias; 2 studies exhibited a moderate risk and 2 a high risk of bias. Dexamethasone was better than nonsteroidal anti-inflammatories for preemptive effectiveness. Meta-analysis for swelling confirmed better results for dexamethasone than for methylprednisolone after 2 days (95% CI = -1.28 to -0.38), 4 days (95% CI = -1.65 to -0.71), 7 days (95% CI = -1.42 to -0.71), and overall (95% CI = -1.25 to -0.72). Dexamethasone was better than methylprednisolone for mouth opening after 4 days (95% CI = 0.18 to 1.07). There is insufficient evidence through meta-analysis to conclude that dexamethasone is better than other nonsteroidal anti-inflammatories or methylprednisolone as a preemptive analgesic. The results of this meta-analysis suggest that dexamethasone is more effective than methylprednisolone for swelling and trismus.

Side effects can enhance treatment response through expectancy effects: an experimental analgesic randomized controlled trial

In randomized controlled trials, medication side effects may lead to beliefs that one is receiving the active intervention and enhance active treatment responses, thereby increasing drug-placebo differences. We tested these hypotheses with an experimental double-blind randomized controlled trial of a nonsteroidal anti-inflammatory drug with and without the addition of atropine to induce side effects. One hundred healthy volunteers were told they would be randomized to either combined analgesics that might produce dry mouth or inert placebos. In reality, they were randomized double blind, double-dummy to 1 of the 4 conditions: (1) 100 mg diclofenac + 1.2 mg atropine, (2) placebo + 1.2 mg atropine, (3) 100 mg diclofenac + placebo, or (4) placebo + placebo, and tested with heat-induced pain. Groups did not differ significantly in demographics, temperature producing moderate pain, state anxiety, or depression. Analgesia was observed in all groups; there was a significant interaction between diclofenac and atropine, without main effects. Diclofenac alone was not better than double-placebo. The addition of atropine increased pain relief more than 3-fold among participants given diclofenac (d = 0.77), but did not enhance the response to placebo (d = 0.09). A chain of mediation analysis demonstrated that the addition of atropine increased dry mouth symptoms, which increased beliefs that one had received the active medication, which, in turn, increased analgesia. In addition to this indirect effect of atropine on analgesia (via dry mouth and beliefs), analyses suggest that among those who received diclofenac, atropine directly increased analgesia. This possible synergistic effect between diclofenac and atropine might warrant future research.

Preemptive Use of Naproxen on Tooth Sensitivity Caused by In-Office Bleaching: A Triple-Blind, Crossover, Randomized Clinical Trial

Objectives:

A triple-blind, randomized, crossover clinical trial evaluated prior use of nonsteroidal anti-inflammatory naproxen on sensitivity reported by patients undergoing in-office tooth bleaching.

Methods and Materials:

Fifty patients were subjected to two sessions of in-office tooth bleaching with 35% hydrogen peroxide in a single application of 40 minutes for two sessions, with an interval of seven days between applications. One hour prior to the procedure, each patient randomly received a single dose of naproxen (500 mg) or placebo. The patient's sensitivity level was evaluated during and immediately after the bleaching using two scales (verbal and visual analog); the verbal scale only was repeated after 24 hours. The effectiveness of the bleaching procedures was evaluated with the Bleachedguide scale. Relative risk to sensitivity was calculated and adjusted by session, while comparison of overall risk was performed by the McNemar test. Data on the sensitivity level for both scales and shade were subjected to the Friedman, Wilcoxon, and Mann-Whitney tests (α=0.05).

Results:

The use of naproxen only decreased the absolute risk and intensity of tooth sensitivity reported immediately after the second session. On the other hand, no measurable effect was observed during or 24 hours after either session. The sequence of drug administration did not affect the bleaching effectiveness.

Conclusions:

Preemptive use of naproxen only reduced tooth sensitivity reported by patients immediately after the second session of bleaching.

Efficacy and safety of a fixed-dose combination of ibuprofen and caffeine in the management of moderate to severe dental pain after third molar extraction

Background

Ibuprofen is an effective analgesic treatment with a ceiling effect at doses above 400 mg. This study compared the combination of ibuprofen 400 mg and caffeine 100 mg with ibuprofen 400 mg monotherapy, caffeine and placebo in the analgesic treatment of moderate to severe acute dental pain following third molar extraction.

Methods

Phase III, active‐/placebo‐controlled, double‐blind, single‐centre, two‐stage, parallel‐group study in adult patients with at least moderate baseline pain intensity. Primary endpoint was defined as the time‐weighted sum of pain relief and pain intensity difference over 8 h (SPRID0–8 h), secondary endpoints included duration of pain relief, time to meaningful pain relief and more.

Results

N = 748 patients were enrolled and N = 562 treated. Mean baseline pain intensity was 7.7 on a 0–10 numerical rating scale. Analysis of SPRID0–8 h demonstrated superior analgesic effects for a single dose of ibuprofen/caffeine versus ibuprofen, caffeine and placebo over 8 h, rescue medication in this stage was requested by more patients on ibuprofen (32.5%) than on ibuprofen/caffeine (16.0%). Median time to meaningful pain relief was shorter for ibuprofen/caffeine (1.13 h) compared with ibuprofen (1.78 h; p = 0.0001). More patients on ibuprofen/caffeine than on ibuprofen reported meaningful pain relief. Adverse events were infrequent and mostly mild or moderate across treatment groups. Tolerability was rated as ‘very good’ or ‘excellent’ by most patients in both treatment groups.

Conclusion

This study demonstrated clinically relevant superiority of ibuprofen/caffeine over monotherapy with ibuprofen in patients with acute dental pain. All treatments were well tolerated.

Significance

This trial showed superior efficacy of 400/100 mg ibuprofen/caffeine, compared to 400 mg ibuprofen alone, for treating acute pain, reflecting that caffeine is an effective analgesic adjuvant. Data on efficacy of 400 mg ibuprofen combined with caffeine for the treatment of acute pain were not available yet.

Multimodal analgesia in moderate-to-severe pain: a role for a new fixed combination of dexketoprofen and tramadol

BACKGROUND

Untreated and under-treated pain represent one of the most pervasive health problems, which is worsening as the population ages and accrues risk for pain. Multiple treatment options are available, most of which have one mechanism of action, and cannot be prescribed at unlimited doses due to the ceiling of efficacy and/or safety concerns. Another limitation of single-agent analgesia is that, in general, pain is due to multiple causes. Combining drugs from different classes, with different and complementary mechanism(s) of action, provides a better opportunity for effective analgesia at reduced doses of individual agents. Therefore, there is a potential reduction of adverse events, often dose-related. Analgesic combinations are recommended by several organizations and are used in clinical practice. Provided the two agents are combined in a fixed-dose ratio, the resulting medication may offer advantages over extemporaneous combinations.

CONCLUSIONS

Dexketoprofen/tramadol (25 mg/75 mg) is a new oral fixed-dose combination offering a comprehensive multimodal approach to moderate-to-severe acute pain that encompasses central analgesic action, peripheral analgesic effect and anti-inflammatory activity, together with a good tolerability profile. The analgesic efficacy of dexketoprofen/tramadol combination is complemented by a favorable pharmacokinetic and pharmacodynamic profile, characterized by rapid onset and long duration of action. This has been well documented in both somatic- and visceral-pain human models. This review discusses the available clinical evidence and the future possible applications of dexketoprofen/tramadol fixed-dose combination that may play an important role in the management of moderate-to-severe acute pain.

Postoperative pain-from mechanisms to treatment

INTRODUCTION

Pain management after surgery continues to be suboptimal; there are several reasons including lack of translation of results from basic science studies and scientific clinical evidence into clinical praxis.

OBJECTIVES

This review presents and discusses basic science findings and scientific evidence generated within the last 2 decades in the field of acute postoperative pain.

METHODS

In the first part of the review, we give an overview about studies that have investigated the pathophysiology of postoperative pain by using rodent models of incisional pain up to July 2016. The second focus of the review lies on treatment recommendations based on guidelines and clinical evidence, eg, by using the fourth edition of the "Acute Pain Management: Scientific Evidence" of the Australian and New Zealand College of Anaesthetists and Faculty of Pain Medicine.

RESULTS

Preclinical studies in rodent models characterized responses of primary afferent nociceptors and dorsal horn neurons as one neural basis for pain behavior including resting pain, hyperalgesia, movement-evoked pain or anxiety- and depression-like behaviors after surgery. Furthermore, the role of certain receptors, mediators, and neurotransmitters involved in peripheral and central sensitization after incision were identified; many of these are very specific, relate to some modalities only, and are unique for incisional pain. Future treatment should focus on these targets to develop therapeutic agents that are effective for the treatment of postoperative pain as well as have few side effects. Furthermore, basic science findings translate well into results from clinical studies. Scientific evidence is able to point towards useful (and less useful) elements of multimodal analgesia able to reduce opioid consumption, improve pain management, and enhance recovery.

CONCLUSION

Understanding basic mechanisms of postoperative pain to identify effective treatment strategies may improve patients' outcome after surgery.

Clinical update on benefit versus risks of oral paracetamol alone or with codeine: still a good option?

BACKGROUND

After decades of worldwide use of paracetamol/acetaminophen as a popular and apparently safe prescription and over-the-counter medicine, the future role of this poorly understood analgesic has been seriously questioned by recent concerns about prenatal, cardiovascular (CV) and hepatic safety, and also about its analgesic efficacy. At the same time the usefulness of codeine in combination products has come under debate.

METHODS

Based on a PubMed database literature search on the terms efficacy, safety, paracetamol, acetaminophen, codeine and their combinations up to and including June 2016, this clinical update reviews the current evidence of the benefit and risks of oral paracetamol alone and with codeine for mild-to-moderate pain in adults, and compares the respective efficacy and safety profiles with those of nonsteroidal anti-inflammatory drugs (NSAIDs).

RESULTS

Whereas there is a clear strong association of NSAID use and gastrointestinal (GI) and CV morbidity and mortality, evidence for paracetamol with and without codeine supports the recommended use even in most vulnerable individuals, such as the elderly, pregnant women, alcoholics, and compromised GI and CV patients. The controversies and widespread misconceptions about the complex hepatic metabolism and potential hepatotoxicity have been corrected by recent reviews, and paracetamol remains the first-line nonopioid analgesic in patients with liver diseases if notes of caution are applied.

CONCLUSION

Due to its safety and tolerability profile paracetamol remained a first-line treatment in many international guidelines. Alone and with codeine it is a safe and effective option in adults, whilst NSAIDs are obviously less safe as alternatives, given the risk of potentially fatal GI and CV adverse effects.

Aspirin for acute treatment of episodic tension-type headache in adults

BACKGROUND

Tension-type headache (TTH) affects about 1 person in 5 worldwide. It is divided into infrequent episodic TTH (fewer than one headache per month), frequent episodic TTH (two to 14 headache days per month), and chronic TTH (15 headache days per month or more). Aspirin is one of a number of analgesics suggested for acute treatment of episodic TTH.

OBJECTIVES

To assess the efficacy and safety of aspirin for acute treatment of episodic tension-type headache (TTH) in adults compared with placebo or any active comparator.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and the Oxford Pain Relief Database from inception to September 2016, and also reference lists of relevant published studies and reviews. We sought unpublished studies by asking personal contacts and searching online clinical trial registers and manufacturers' websites.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled studies (parallel-group or cross-over) using oral aspirin for symptomatic relief of an acute episode of TTH. Studies had to be prospective, with participants aged 18 years or over, and include at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and extracted data. For various outcomes (predominantly those recommended by the International Headache Society (IHS)), we calculated the risk ratio (RR) and number needed to treat for one additional beneficial outcome (NNT), one additional harmful outcome (NNH), or to prevent one event (NNTp) for oral aspirin compared to placebo or an active intervention.We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We included five studies enrolling adults with frequent episodic TTH; 1812 participants took medication, of which 767 were included in comparisons of aspirin 1000 mg with placebo, and 405 in comparisons of aspirin 500 mg or 650 mg with placebo. Not all of these participants provided data for outcomes of interest in this review. Four studies specified using IHS diagnostic criteria; one predated commonly recognised criteria, but described comparable characteristics and excluded migraine. All participants treated headaches of at least moderate pain intensity.None of the included studies were at low risk of bias across all domains considered, although for most studies and domains this was likely to be due to inadequate reporting rather than poor methods. We judged one study to be at high risk of bias due to small size.There were no data for aspirin at any dose for the IHS preferred outcome of being pain free at two hours, or for being pain free at any other time, and only one study provided data equivalent to having no or mild pain at two hours (very low quality evidence). Use of rescue medication was lower with aspirin 1000 mg than with placebo (2 studies, 397 participants); 14% of participants used rescue medication with aspirin 1000 mg compared with 31% with placebo (NNTp 6.0, 95% confidence interval (CI) 4.1 to 12) (low quality evidence). Two studies (397 participants) reported a Patient Global Evaluation at the end of the study; we combined the top two categories for both studies to determine the number of participants who were 'satisfied' with treatment. Aspirin 1000 mg produced more satisfied participants (55%) than did placebo (37%) (NNT 5.7, 95% CI 3.7 to 12) (very low quality evidence).Adverse events were not different between aspirin 1000 mg and placebo (RR 1.1, 95% CI 0.8 to 1.5), or aspirin 500 mg or 650 mg and placebo (RR 1.3, 95% CI 0.8 to 2.0) (low quality evidence). Studies reported no serious adverse events.The quality of the evidence using GRADE comparing aspirin doses between 500 mg and 1000 mg with placebo was low or very low. Evidence was downgraded because of the small number of studies and events, and because the most important measures of efficacy were not reported.There were insufficient data to compare aspirin with any active comparator (paracetamol alone, paracetamol plus codeine, peppermint oil, or metamizole) at any of the doses tested.

AUTHORS' CONCLUSIONS

A single dose of aspirin between 500 mg and 1000 mg provided some benefit in terms of less frequent use of rescue medication and more participants satisfied with treatment compared with placebo in adults with frequent episodic TTH who have an acute headache of moderate or severe intensity. There was no difference between a single dose of aspirin and placebo for the number of people experiencing adverse events. The amount and quality of the evidence was very limited and should be interpreted with caution.

PANSAID - PAracetamol and NSAID in combination: study protocol for a randomised trial

BACKGROUND

Effective postoperative pain management is essential for the rehabilitation of the surgical patient. No 'gold standard' exists after total hip arthroplasty (THA) and combinations of different nonopioid medications are used with virtually no evidence for additional analgesic efficacy compared to monotherapy. The objective of this trial is to investigate the analgesic effects and safety of paracetamol and ibuprofen alone and in combination in different dosages after THA.

METHODS

PANSAID is a placebo-controlled, parallel four-group, multicentre trial with centralised computer-generated allocation sequence and allocation concealment and with varying block size and stratification by site. Blinding of assessor, investigator, caregivers, patients and statisticians. Patients are randomised to four groups: (A) paracetamol 1 g × 4 and ibuprofen 400 mg × 4, (B) paracetamol 1 g × 4 and placebo, (C) placebo and ibuprofen 400 mg × 4 and (D) paracetamol 0.5 g × 4 and ibuprofen 200 mg. The two co-primary outcomes are 24-h consumption of morphine and number of patients with one or more serious adverse events within 90 days after surgery. Secondary outcomes are pain scores during mobilisation and at rest at 6 and 24 h postoperatively, and number of patients with one or more adverse events within 24 h postoperatively. Inclusion criteria are patients scheduled for unilateral, primary THA; age above 18 years; ASA status 1-3; BMI >18 and <40 kg/m²; women must not be pregnant; and provision of informed consent. Exclusion criteria are patients who cannot cooperate with the trial; participation in another trial; patients who cannot understand/speak Danish; daily use of strong opioids; allergy against trial medication; contraindications against ibuprofen; alcohol and/or drug abuse. A total of 556 eligible patients are needed to detect a difference of 10 mg morphine i.v. the first 24 h postoperatively with a standard deviation of 20 mg and a family wise type 1 error rate of 0.025 (two-sided) and a type 2 error rate of 0.10 for the six possible comparisons of the four intervention groups.

DISCUSSION

We started recruiting patients in December 2015 and expect to finish in September 2017. Data analysis will be from September 2017 to October 2017 and manuscript submission ultimo 2017.

TRIAL REGISTRATION

EudraCT: 2015-002239-16 (12/8-15); ClinicalTrials.gov: NCT02571361 . Registered on 7 October 2015.

Ketoprofen for episodic tension-type headache in adults

BACKGROUND

Tension-type headache (TTH) affects about 1 person in 5 worldwide. It is divided into infrequent episodic TTH (fewer than one headache day per month), frequent episodic TTH (2 to 14 headache days per month), and chronic TTH (15 headache days a month or more). Ketoprofen is one of a number of analgesics suggested for acute treatment of headaches in frequent episodic TTH.

OBJECTIVES

To assess the efficacy and safety of ketoprofen for treatment of episodic TTH in adults compared with placebo or any active comparator.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and the Oxford Pain Relief Database up to May 2016, and also reference lists of relevant published studies and reviews. We sought unpublished studies by asking personal contacts and searching online clinical trial registers and manufacturers' websites.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled studies (parallel-group or cross-over) using oral ketoprofen for symptomatic relief of an acute episode of TTH. Studies had to be prospective, with participants aged 18 years or over, and include at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and extracted data. We used the numbers of participants achieving each outcome to calculate the risk ratio (RR) and number needed to treat for one additional beneficial outcome (NNT) or one additional harmful outcome (NNH) for oral ketoprofen compared to placebo or an active intervention for a range of outcomes, predominantly those recommended by the International Headache Society (IHS).We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We included four studies, all of which enrolled adults with frequent episodic TTH. They all specified using the IHS diagnostic criteria and reported mean baseline pain of at least moderate intensity. While 1253 people with TTH participated in these studies, the numbers available for any analysis were lower than this because outcomes were inconsistently reported and because many participants received active comparators.None of the included studies were at low risk of bias across all domains considered, although for most studies and domains this was likely to be due to inadequate reporting rather than poor methods. We judged one study to be at high risk of bias due to small size.Useful information was available only for ketoprofen 25 mg. For the IHS preferred outcome of being pain-free at two hours the NNT for ketoprofen 25 mg compared with placebo was 9.0 (95% confidence interval (CI) 4.8 to 72) in two studies (272 participants; low quality evidence). The NNT was 3.7 (95% CI 2.6 to 6.3) for pain-free or mild pain at two hours in two studies (272 participants; moderate quality evidence). Fewer people needed rescue medication with ketoprofen 25 mg than with placebo, with a number needed to treat to prevent one event (NNTp) of 6.2 (95% CI 4.3 to 11) in three studies (605 participants; moderate quality evidence). The number of participants reporting any adverse event was higher with ketoprofen 25 mg than placebo (NNH 15, (95% CI 8.7 to 45)) in three studies (651 participants with 66 events; low quality evidence). Most events were of mild to moderate intensity.Ketoprofen 25 mg was not different from paracetamol 1000 mg in two studies with 276 participants for any efficacy outcomes (low to moderate quality evidence); the RR for pain-free at two hours was 1.3 (95% CI 0.9 to 2.0). The number of participants reporting any adverse event was higher with ketoprofen 25 mg than with paracetamol (NNH 17, 95% CI 8.9 to 130)) in two studies (582 participants, 68 events; low quality evidence).Studies reported no serious adverse events.We judged the quality of the evidence comparing ketoprofen 25 mg with placebo or paracetamol 1000 mg as moderate to very low. Where evidence was downgraded it was because of the small number of studies and events.

AUTHORS' CONCLUSIONS

Ketoprofen 25 mg provided a small benefit compared with placebo in terms of being pain-free at two hours or having mild or no pain at two hours for people with frequent episodic TTH who have an acute headache of moderate or severe intensity. Its use was associated with more people experiencing adverse events. Ketoprofen 25 mg was not superior to paracetamol 1000 mg for any efficacy outcome.

Variations in the Use of Perioperative Multimodal Analgesic Therapy

BACKGROUND

Practice guidelines for perioperative pain management recommend that multimodal analgesic therapy should be used for all postsurgical patients. However, the proportion of patients who actually receive this evidence-based approach is unknown. The objective of this study was to describe hospital-level patterns in the utilization of perioperative multimodal analgesia.

METHODS

Data for the study were obtained from the Premier Research Database. Patients undergoing below-knee amputation, open lobectomy, total knee arthroplasty, and open colectomy between 2007 and 2014 were included in the analysis. Patients were considered to have multimodal therapy if they received one or more nonopioid analgesic therapies. Mixed-effects logistic regression models were used to estimate the hospital-specific frequency of multimodal therapy use while adjusting for the case mix of patients and hospital characteristics and accounting for random variation.

RESULTS

The cohort consisted of 799,449 patients who underwent a procedure at 1 of 315 hospitals. The mean probability of receiving multimodal therapy was 90.4%, with 95% of the hospitals having a predicted probability between 42.6 and 99.2%. A secondary analysis examined whether patients received two or more nonopioid analgesics, which gave an average predicted probability of 54.2%, with 95% of the hospitals having a predicted probability between 9.3 and 93.2%.

CONCLUSIONS

In this large nationwide sample of surgical admissions in the United States, the authors observed tremendous variation in the utilization of multimodal therapy not accounted for by patient or hospital characteristics. Efforts should be made to identify why there are variations in the use of multimodal analgesic therapy and to promote its adoption in appropriate patients.

Analgesic efficacy of celecoxib in patients after oral surgery: special reference to time to onset of analgesia and duration of analgesic effect

PURPOSE

Cyclooxygenase-2 inhibitor celecoxib is also used in the dental field for analgesia. However, there are few reports on the time to onset and duration of analgesia. We investigated the analgesic effect of celecoxib after oral surgery.

METHODS

A total of 138 patients undergoing unilateral mandibular third molar surgery under local anesthesia were enrolled. After surgery, the patients who felt pain and requested an analgesic were instructed to take celecoxib 400 mg and to record the time. Primary efficacy outcome measures were time to onset of analgesia. In addition, the conditions of pain at the time of taking celecoxib, at the onset time of analgesia, and 2 and 6 h after taking the drug were recorded. Pain assessments were evaluated using a 10-cm visual analog scale and four-point verbal rating score. These data were documented in the questionnaire forms handed to the patients and retrieved by post.

RESULTS

Effective responses without missing were returned from 103 patients. The median time to onset of the efficacy was 35 min. The pain scales at celecoxib administration was significantly higher compared with the time of onset of analgesia, 2 hours after administraton and 6 hours hours administration (P<0.05, respectively). The pain scales at the onset time of analgesia were significantly higher compared to that after 2 or 6 h of taking the drug (P<0.05, respectively). There were no statistically significant differences in the pain scales between 2 and 6 h after taking the drug (P>0.05).

CONCLUSION

The analgesic effect of celecoxib was exhibited quickly and sustained after oral surgery.

Randomized clinical trial of dexketoprofen/tramadol 25 mg/75 mg in moderate-to-severe pain after total hip arthroplasty

Background. The aim was to evaluate the analgesic efficacy and safety of the dexketoprofen/tramadol 25 mg/75 mg fixed-dose combination vs dexketoprofen (25 mg) and tramadol (100 mg) in moderate-to-severe acute pain after total hip arthroplasty.

Methods. This was a randomized, double-blind, parallel-group study in patients experiencing pain of at least moderate intensity on the day after surgery, compared with placebo at first administration to validate the pain model. The study drug was administered orally every 8 h throughout a 5 day period. Rescue medication, metamizole 500 mg, was available during the treatment period. The evaluation of efficacy was based on patient assessments of pain intensity and pain relief. The primary end point was the mean sum of the pain intensity difference values throughout the first 8 h (SPID₈).

Results. Overall, 641 patients, mean age 62 (range 29–80) yr, were analysed; mean (sd) values of SPID₈ were 247 (157) for dexketoprofen/tramadol, 209 (155) for dexketoprofen, 205 (146) for tramadol, and 151 (159) for placebo. The primary analysis confirmed the superiority of the combination over dexketoprofen 25 mg (P=0.019; 95% confidence interval 6.4–73) and tramadol 100 mg (P=0.012; 95% confidence interval 9.5–76). The single components were superior to placebo (P<0.05), confirming model sensitivity. Most secondary analyses supported the superiority of the combination. The incidence of adverse drug reactions was low and similar among active treatment groups.

Conclusion. The efficacy results confirmed the superiority of dexketoprofen/tramadol over its single components, even at higher doses (tramadol), with a safety profile fully in line with that previously known for these agents in monotherapy.

Clinical trial registration. EudraCT 2012-004548-31 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=eudract_number:2012-004548-31);

ClinicalTrials.gov NCT01902134 (https://www.clinicaltrials.gov/ct2/show/NCT01902134?term=NCT01902134&rank=1).

Ibuprofen and/or paracetamol (acetaminophen) for pain relief after surgical removal of lower wisdom teeth, a Cochrane systematic review

This paper compares the beneficial and harmful effects of paracetamol, ibuprofen and the novel combination of both in a single tablet for pain relief following the surgical removal of lower wisdom teeth. In this systematic review only randomised controlled double-blinded clinical trials were included. We calculated the proportion of patients with at least 50% pain relief at 2 and 6 hours post dosing, along with the proportion of participants using rescue medication at 6 and 8 hours. Adverse events were also analysed. Data was meta-analysed where possible. Seven studies were included with a total of 2,241 participants enrolled. Ibuprofen 400 mg is superior to 1,000 mg paracetamol with a risk ratio for at least 50% pain relief at 6 hours of 1.47 (95% confidence interval [CI] 1.28 to 1.69). For the combined drug, the risk ratio for at least 50% maximum pain relief over 6 hours is 1.77 (95% CI 1.32 to 2.39) based on total pain relief (TOTPAR) data. There is high quality evidence that ibuprofen is superior to paracetamol. The novel combination drug shows encouraging results when compared to the single drugs (based on two trials).

Nefopam Reduces Dysesthesia after Percutaneous Endoscopic Lumbar Discectomy

Background

Neuropathic pain, including paresthesia/dysesthesia in the lower extremities, always develops and remains for at least one month, to variable degrees, after percutaneous endoscopic lumbar discectomy (PELD). The recently discovered dual analgesic mechanisms of action, similar to those of antidepressants and anticonvulsants, enable nefopam (NFP) to treat neuropathic pain. This study was performed to determine whether NFP might reduce the neuropathic pain component of postoperative pain.

Methods

Eighty patients, who underwent PELD due to herniated nucleus pulposus (HNP) at L4-L5, were randomly divided into two equal groups, one receiving NFP (with a mixture of morphine and ketorolac) and the other normal saline (NS) with the same mixture. The number of bolus infusions and the infused volume for 3 days were compared in both groups. The adverse reactions (ADRs) in both groups were recorded and compared. The neuropathic pain symptom inventory (NPSI) score was compared in both groups on postoperative days 1, 3, 7, 30, 60, and 90.

Results

The mean attempted number of bolus infusions, and effective infused bolus volume for 3 days was lower in the NFP group for 3 days. The most commonly reported ADRs were nausea, dizziness, and somnolence, in order of frequency in the NFP group. The median NPSI score, and all 5 median sub-scores in the NFP group, were significantly lower than that of the NS group until postoperative day 30.

Conclusions

NFP significantly reduced the neuropathic pain component, including paresthesia/dysesthesia until 1 month after PELD. The common ADRs were nausea, dizziness, somnolence, and ataxia.

Single dose of diclofenac or meloxicam for control of pain, facial swelling, and trismus in oral surgery

Background

Postoperative pain associated with removal of mandibular third molars has been documented from moderate to severe during the first 24 hours after surgery, with pain peaking between 6 and 8 hours when a conventional local anesthetic is used. Dental pain is largely inflammatory, and evidence-based medicine has shown that nonsteroidal anti-inflammatory drugs are the best analgesics for dental pain. The aim of this study was to compare the analgesic, anti-inflammatory and anti-trismus effect of a single dose of diclofenac and meloxicam after mandibular third molar extraction.

Material and Methods

A total of 36 patients were randomized into two treatment groups, each with 18 patients, using a series of random numbers: Group A, was administered 100 mg of diclofenac; and Group B, 15 mg of meloxicam. Drugs were administered orally 1 hour prior to surgery. We evaluated pain intensity, analgesic consumption, swelling, as well as trismus.

Results

The results of this study showed that patients receiving 15 mg of meloxicam had less postoperative pain (P=0.04) and better aperture than those receiving 100 mg of diclofenac (P=0.03). The meloxicam group presented less swelling than diclofenac group; however, significant statistical differences were not observed.

Conclusions

Data of this double-blind, randomized, parallel-group clinical trial demonstrated that patients receiving 15 mg of preoperative meloxicam had a better postoperative analgesia and anti-trismus effect compared with who were given 100 mg of diclofenac after third molar extractions.

Key words:Diclofenac, meloxicam, dental pain, trismus, third molar surgery.

Adverse events associated with single dose oral analgesics for acute postoperative pain in adults - an overview of Cochrane reviews

BACKGROUND

This is an update of a Cochrane overview published in Issue 9, 2011; that overview considered both efficacy and adverse events. This overview considers adverse events, with efficacy dealt with in a separate overview.Thirty-nine Cochrane reviews of randomised trials have examined the adverse events associated with individual drug interventions in acute postoperative pain. This overview brings together the results of those individual reviews.

OBJECTIVES

To provide an overview of adverse event rates associated with single-dose oral analgesics, compared with placebo, for acute postoperative pain in adults.

METHODS

We identified systematic reviews in The Cochrane Database of Systematic Reviews on The Cochrane Library through a simple search strategy. All reviews were overseen by a single review group. We extracted information related to participants experiencing any adverse event, and reports of serious adverse events, and deaths from the individual reviews.

MAIN RESULTS

Information was available from 39 Cochrane reviews for 41 different analgesics or analgesic combinations (51 drug/dose/formulations) tested in single oral doses in participants with moderate or severe postoperative pain. This involved around 350 unique studies involving about 35,000 participants. Most studies involved younger participants with pain following removal of molar teeth.For most nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol, and combinations not containing opioids, there were few examples where participants experienced significantly more or fewer adverse events than with placebo. For aspirin 1000 mg and diflunisal 1000 mg, opioids, or fixed-dose combination drugs containing opioids, participants typically experienced significantly more adverse events than with placebo. Studies of combinations of ibuprofen and paracetamol reported significantly fewer adverse events.Serious adverse events were rare, occurring a rate of about 1 in 3200 participants.Most reviews did not report specific adverse events.

AUTHORS' CONCLUSIONS

Despite ongoing problems with the measurement, recording, and reporting of adverse events in clinical trials and in systematic reviews, the large amount of information available for single oral doses of analgesics provides evidence that adverse events rates are generally similar with active drug and placebo in these circumstances, except at higher doses of some drugs, and in combinations including opioids.

How effective are common medications: a perspective based on meta-analyses of major drugs

The vastness of clinical data and the progressing specialization of medical knowledge may lead to misinterpretation of medication efficacy. To show a realistic perspective on drug efficacy we present meta-analyses on some of the most commonly used pharmacological interventions. For each pharmacological intervention we present statistical indexes (absolute risk or response difference, percentage response ratio, mean difference, standardized mean difference) that are often used to represent efficacy. We found that some of the medications have relatively low effect sizes with only 11 out of 17 of them showing a minimal clinically important difference. Efficacy was often established based on surrogate outcomes and not the more relevant patient-oriented outcomes. As the interpretation of the efficacy of medication is complex, more training for physicians might be needed to get a more realistic view of drug efficacy. That could help prevent harmful overtreatment and reinforce an evidence-based, but personalized medicine.

Single dose oral analgesics for acute postoperative pain in adults - an overview of Cochrane reviews

BACKGROUND

This is an updated version of the original Cochrane overview published in Issue 9, 2011. That overview considered both efficacy and adverse events, but adverse events are now dealt with in a separate overview.Thirty-nine Cochrane reviews of randomised trials have examined the analgesic efficacy of individual drug interventions in acute postoperative pain. This overview brings together the results of those individual reviews and assesses the reliability of available data.

OBJECTIVES

To summarise the efficacy of pharmaceutical interventions for acute pain in adults with at least moderate pain following surgery who have been given a single dose of oral analgesic.

METHODS

We identified systematic reviews in the Cochrane Database of Systematic Reviews in The Cochrane Library through a simple search strategy. All reviews were overseen by a single review group, had a standard title, and had as their primary outcome the number of participants with at least 50% pain relief over four to six hours compared with placebo. For individual reviews, we extracted the number needed to treat for an additional beneficial outcome (NNT) for this outcome for each drug/dose combination, and also the percentage of participants achieving at least 50% maximum pain relief, the mean of mean or median time to remedication, and the percentage of participants remedicating by six, eight, 12, or 24 hours. Where there was adequate information for pairs of drug and dose (at least 200 participants, in at least two studies), we defined the addition of four comparisons of typical size (400 participants in total) with zero effect as making the result potentially subject to publication bias and therefore unreliable.

MAIN RESULTS

The overview included 39 separate Cochrane Reviews with 41 analyses of single dose oral analgesics tested in acute postoperative pain models, with results from about 50,000 participants in approximately 460 individual studies. The individual reviews included only high-quality trials of standardised design, methods, and efficacy outcome reporting. No statistical comparison was undertaken.Reliable results (high quality information) were obtained for 53 pairs of drug and dose in painful postsurgical conditions; these included various fixed dose combinations, and fast acting formulations of some analgesics. NNTs varied from about 1.5 to 20 for at least 50% maximum pain relief over four to six hours compared with placebo. The proportion of participants achieving this level of benefit varied from about 30% to over 70%, and the time to remedication varied from two hours (placebo) to over 20 hours. Good (low) NNTs were obtained with ibuprofen 200 mg plus paracetamol (acetaminophen) 500 mg (NNT compared with placebo 1.6; 95% confidence interval 1.5 to 1.8), ibuprofen fast acting 200 mg (2.1; 1.9 to 2.3); ibuprofen 200 mg plus caffeine 100 mg (2.1; 1.9 to 3.1), diclofenac potassium 50 mg (2.1; 1.9 to 2.5), and etoricoxib 120 mg (1.8; 1.7 to 2.0). For comparison, ibuprofen acid 400 mg had an NNT of 2.5 (2.4 to 2.6). Not all participants had good pain relief and, for many pairs of drug and dose, 50% or more did not achieve at least 50% maximum pain relief over four to six hours.Long duration of action (eight hours or greater) was found for etoricoxib 120 mg, diflunisal 500 mg, paracetamol 650 mg plus oxycodone 10 mg, naproxen 500/550 mg, celecoxib 400 mg, and ibuprofen 400 mg plus paracetamol 1000 mg.There was no evidence of analgesic effect for aceclofenac 150 mg, aspirin 500 mg, and oxycodone 5 mg (low quality evidence). No trial data were available in reviews of acemetacin, meloxicam, nabumetone, nefopam, sulindac, tenoxicam, and tiaprofenic acid. Inadequate amounts of data were available for nine drugs and doses, and data potentially susceptible to publication bias for 13 drugs and doses (very low quality evidence).

AUTHORS' CONCLUSIONS

There is a wealth of reliable evidence on the analgesic efficacy of single dose oral analgesics. Fast acting formulations and fixed dose combinations of analgesics can produce good and often long-lasting analgesia at relatively low doses. There is also important information on drugs for which there are no data, inadequate data, or where results are unreliable due to susceptibility to publication bias. This should inform choices by professionals and consumers.

Ibuprofen for acute treatment of episodic tension-type headache in adults

BACKGROUND

Tension-type headache (TTH) affects about one person in five worldwide. It is divided into infrequent episodic TTH (fewer than one headache per month), frequent episodic TTH (1 to 14 headaches per month), and chronic TTH (15 headaches a month or more). Ibuprofen is one of a number of analgesics suggested for acute treatment of headaches in frequent episodic TTH.

OBJECTIVES

To assess the efficacy and safety of oral ibuprofen for treatment of acute episodic TTH in adults.

SEARCH METHODS

We searched CENTRAL (The Cochrane Library), MEDLINE, EMBASE, and our own in-house database to January 2015. We sought unpublished studies by asking personal contacts and searching on-line clinical trial registers and manufacturers' websites.

SELECTION CRITERIA

We included randomised, placebo-controlled studies (parallel-group or cross-over) using oral ibuprofen for symptomatic relief of an acute episode of TTH. Studies had to be prospective and include at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion, and extracted data. Numbers of participants achieving each outcome were used to calculate risk ratio (RR) and number needed to treat for an additional beneficial outcome (NNT) or number needed to treat for an additional harmful outcome (NNH) of oral ibuprofen compared to placebo for a range of outcomes, predominantly those recommended by the International Headache Society (IHS).

MAIN RESULTS

We included 12 studies, all of which enrolled adult participants with frequent episodic TTH. Nine used the IHS diagnostic criteria, but two used the older classification of the Ad Hoc Committee, and one did not describe diagnostic criteria but excluded participants with migraines. While 3094 people with TTH participated in these studies, the numbers available for any form of analysis were lower than this; placebo was taken by 733, standard ibuprofen 200 mg by 127, standard ibuprofen 400 mg by 892, and fast-acting ibuprofen 400 mg by 230. Participants had moderate or severe pain at the start of treatment. Other participants were either in studies not reporting outcomes we could analyse, or were given one of several active comparators in single studies.For the IHS-preferred outcome of being pain free at 2 hours the NNT for ibuprofen 400 mg (all formulations) compared with placebo was 14 (95% confidence interval (CI), 8.4 to 47) in four studies, with no significant difference from placebo at 1 hour (moderate quality evidence). The NNT was 5.9 (4.2 to 9.5) for the global evaluation of 'very good' or 'excellent' in three studies (moderate quality evidence). No study reported the number of participants experiencing no worse than mild pain at 1 or 2 hours. The use of rescue medication was lower with ibuprofen 400 mg than with placebo, with the number needed to treat to prevent one event (NNTp) of 8.9 (5.6 to 21) in two studies (low quality evidence).Adverse events were not different between ibuprofen 400 mg and placebo; RR 1.1 (0.64 to 1.7) (high-quality evidence). No serious adverse events were reported.

AUTHORS' CONCLUSIONS

Ibuprofen 400 mg provides an important benefit in terms of being pain free at 2 hours for a small number of people with frequent episodic tension-type headache who have an acute headache with moderate or severe initial pain. There is no information about the lesser benefit of no worse than mild pain at 2 hours.

Single dose oral ibuprofen plus caffeine for acute postoperative pain in adults

BACKGROUND

There is good evidence that combining two different analgesics in fixed doses in a single tablet can provide better pain relief in acute pain and headache than either drug alone, and that the drug-specific benefits are essentially additive. This appears to be broadly true in postoperative pain and migraine headache across a range of different drug combinations, and when tested in the same and different trials. Adding caffeine to analgesics also increases the number of people obtaining good pain relief. Combinations of ibuprofen and caffeine are available without prescription in some parts of the world.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of ibuprofen plus caffeine for moderate to severe postoperative pain, using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Relief Database, two clinical trial registries, and the reference lists of articles. The date of the most recent search was 1 February 2015.

SELECTION CRITERIA

Randomised, double-blind, placebo- or active-controlled clinical trials of single dose oral ibuprofen plus caffeine for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered trials for inclusion in the review, assessed risk of bias, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants with at least 50% pain relief over six hours prescribed either ibuprofen plus caffeine or placebo. We calculated the risk ratio (RR) and number needed to treat to benefit (NNT). We used information on the use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse effects.

MAIN RESULTS

We identified five randomised, double-blind studies with 1501 participants, but only four had been published and had relevant outcome data. These four studies were of high quality, although two of the studies were small.Both ibuprofen 200 mg + caffeine 100 mg and ibuprofen 100 mg + caffeine 100 mg produced significantly more participants than placebo who achieved at least 50% of maximum pain relief over six hours, and both doses significantly reduced remedication rates (moderate quality evidence). For at least 50% of maximum pain relief, the NNT was 2.1 (95% confidence interval 1.8 to 2.5) for ibuprofen 200 mg + caffeine 100 mg (four studies, 334 participants) and 2.4 (1.9 to 3.1) for ibuprofen 100 mg + caffeine 100 mg (two studies, 200 participants) (moderate quality evidence). These values were close to those predicted by published models for combination analgesics in acute pain, and were supported by low (good) NNT values for prevention of remedication.Adverse event rates were low, and no sensible analysis was possible.

AUTHORS' CONCLUSIONS

For ibuprofen 200 mg + caffeine 100 mg particularly, the low NNT value is among the lowest (best) values for analgesics in this pain model. The combination is not commonly available, but can be probably be achieved by taking a single 200 mg ibuprofen tablet with a cup of modestly strong coffee or caffeine tablets. In principle, this can deliver good analgesia at lower doses of ibuprofen.

Single dose oral diclofenac for acute postoperative pain in adults

BACKGROUND

Diclofenac is a nonsteroidal anti-inflammatory drug, available as a potassium salt (immediate release) or sodium salt (enteric coated to suppress dissolution in the stomach). This review updates an earlier review published in the Cochrane Database of Systematic Reviews (Issue 2, 2009) entitled 'Single dose oral diclofenac for acute postoperative pain in adults'.

OBJECTIVES

To assess the analgesic efficacy and adverse effects of a single oral dose of diclofenac for moderate to severe postoperative pain, using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Relief Database, two clinical trial registries, and the reference lists of articles. The date of the most recent search was 9 March 2015.

SELECTION CRITERIA

Randomised, double-blind, placebo-controlled clinical trials of single dose, oral diclofenac (sodium or potassium) for acute postoperative pain in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered studies for inclusion in the review, assessed risk of bias, and extracted data. We used the area under the pain relief versus time curve to derive the proportion of participants with at least 50% pain relief over six hours prescribed either diclofenac or placebo. We calculated the risk ratio (RR) and number needed to treat to benefit (NNT). We used information on the use of rescue medication to calculate the proportion of participants requiring rescue medication and the weighted mean of the median time to use. We also collected information on adverse effects.

MAIN RESULTS

This update included three new studies, providing a 26% increase in participants in comparisons between diclofenac and placebo. We included 18 studies involving 3714 participants, 1902 treated with diclofenac and 1007 with placebo. This update has also changed the focus of the review, examining the effects of formulation in more detail than previously. This is a result of increased understanding of the importance of speed of onset in determining analgesic efficacy in acute pain.The largest body of information, for diclofenac potassium 50 mg, in seven studies, produced an NNT for at least 50% of maximum pain relief compared with placebo of 2.1 (95% confidence interval (CI) 1.9 to 2.5) (high quality evidence). There was a graded improvement in efficacy as doses rose from 25 mg to 100 mg, both for participants achieving at least 50% maximum pain relief, and for remedication within 6 to 8 hours. Fast-acting formulations (dispersible products, solutions, and softgel formulations) had a similar efficacy for a 50 mg dose, with an NNT of 2.4 (2.0 to 3.0). Diclofenac sodium in a small number of studies produced a lesser effect, with an NNT of 6.6 (4.1 to 17) for the 50 mg dose.Adverse event rates were low in these single dose studies, with no difference between diclofenac and placebo (moderate quality evidence).

AUTHORS' CONCLUSIONS

Diclofenac potassium provides good pain relief at 25 mg, 50 mg, and 100 mg doses. Diclofenac sodium has limited efficacy and should probably not be used in acute pain.

Effects of food on pharmacokinetics of immediate release oral formulations of aspirin, dipyrone, paracetamol and NSAIDs - a systematic review

Aims

It is common to advise that analgesics, and especially non-steroidal anti-inflammatory drugs (NSAIDs), be taken with food to reduce unwanted gastrointestinal adverse effects. The efficacy of single dose analgesics depends on producing high, early, plasma concentrations; food may interfere with this. This review sought evidence from single dose pharmacokinetic studies on the extent and timing of peak plasma concentrations of analgesic drugs in the fed and fasting states.

Methods

A systematic review of comparisons of oral analgesics in fed and fasting states published to October 2014 reporting kinetic parameters of bioavailability, time to maximum plasma concentration (t_max), and its extent (C_max) was conducted. Delayed-release formulations were not included.

Results

Bioavailability was not different between fasted and fed states. Food typically delayed absorption for all drugs where the fasting t_max was less than 4 h. For the common analgesics (aspirin, diclofenac, ibuprofen, paracetamol) fed t_max was 1.30 to 2.80 times longer than fasted t_max. C_max was typically reduced, with greater reduction seen with more rapid absorption (fed C_max only 44–85% of the fasted C_max for aspirin, diclofenac, ibuprofen and paracetamol).

Conclusion

There is evidence that high, early plasma concentrations produces better early pain relief, better overall pain relief, longer lasting pain relief and lower rates of remedication. Taking analgesics with food may make them less effective, resulting in greater population exposure. It may be time to rethink research priorities and advice to professionals, patients and the public.

Dexketoprofen/tramadol: randomised double-blind trial and confirmation of empirical theory of combination analgesics in acute pain

Background

Combination analgesics are effective in acute pain, and a theoretical framework predicts efficacy for combinations. The combination of dexketoprofen and tramadol is untested, but predicted to be highly effective.

Methods

This was a randomised, double-blind, double-dummy, parallel-group, placebo-controlled, single-dose trial in patients with moderate or severe pain following third molar extraction. There were ten treatment arms, including dexketoprofen trometamol (12.5 mg and 25 mg) and tramadol hydrochloride (37.5 mg and 75 mg), given as four different fixed combinations and single components, with ibuprofen 400 mg as active control as well as a placebo control. The study objective was to evaluate the superior analgesic efficacy and safety of each combination and each single agent versus placebo. The primary outcome was the proportion of patients with at least 50 % max TOTPAR over six hours.

Results

606 patients were randomised and provided at least one post-dose assessment. All combinations were significantly better than placebo. The highest percentage of responders (72 %) was achieved in the dexketoprofen trometamol 25 mg plus tramadol hydrochloride 75 mg group (NNT 1.6, 95 % confidence interval 1.3 to 2.1). Addition of tramadol to dexketoprofen resulted in greater peak pain relief and greater pain relief over the longer term, particularly at times longer than six hours (median duration of 8.1 h). Adverse events were unremarkable.

Conclusions

Dexketoprofen trometamol 25 mg combined with tramadol hydrochloride 75 mg provided good analgesia with rapid onset and long duration in a model of moderate to severe pain. The results of the dose finding study are consistent with pre-trial calculations based on empirical formulae.

Trial registration

EudraCT (2010-022798-32); Clinicaltrials.gov (NCT01307020).

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-015-0541-5) contains supplementary material, which is available to authorized users.

Overview of systematic reviews - a new type of study. Part II

CONTEXT AND OBJECTIVE

Overviews of Systematic Reviews (OoRs) are a new type of study in which multiple evidence from systematic reviews (SRs) is compiled into an accessible and useful document. The aim here was to describe the state of the art and critically assess Cochrane OoRs that have been published.

DESIGN AND SETTING

Descriptive study conducted at a research center.

METHODS

The OoRs identified through the filter developed in Part I of this study were evaluated in five domains: methodological quality; quality of evidence; implications for practice; general profile of OoRs; and length of work.

RESULTS

All 13 OoRs included had high methodological quality. Some OoRs did not present sufficient data to judge the quality of evidence; using sensitivity analysis, the quality of evidence of the OoRs increased. Regarding implications for practice, 64% of the interventions were judged as beneficial or harmful, while 36% of them showed insufficient evidence for judgment. It is expected (with 95% confidence interval) that one OoR will include 9,462 to 64,469 patients, 9 to 29 systematic reviews and 80 to 344 primary studies, and assess 6 to 21 interventions; and that 50 to 92% of OoRs will produce meta-analysis. The OoRs generated 2 to 26 meta-analyses over a period of 18 to 31 months.

CONCLUSION

The OoRs presented high methodological quality; the quality of evidence tended to be moderate/high; most interventions were judged to be beneficial/harmful; the mean length of work was 24 months. The OoR profile adds power to decision-making.

Assay sensitivity of pain intensity versus pain relief in acute pain clinical trials: ACTTION systematic review and meta-analysis

The magnitude of the effect size of an analgesic intervention can be influenced by several factors, including research design. A key design component is the choice of the primary endpoint. The purpose of this meta-analysis was to compare the assay sensitivity of 2 efficacy paradigms: pain intensity (calculated using summed pain intensity difference [SPID]) and pain relief (calculated using total pain relief [TOTPAR]). A systematic review of the literature was performed to identify acute pain studies that calculated both SPIDs and TOTPARs within the same study. Studies were included in this review if they were randomized, double-blind, placebo-controlled investigations involving medications for postsurgical acute pain and if enough data were provided to calculate TOTPAR and SPID standardized effect sizes. Based on a meta-analysis of 45 studies, the mean standardized effect size for TOTPAR (1.13) was .11 higher than that for SPID (1.02; P = .01). Mixed-effects meta-regression analyses found no significant associations between the TOTPAR - SPID difference in standardized effect size and trial design characteristics. Results from this review suggest that for acute pain studies, utilizing TOTPAR to assess pain relief may be more sensitive to treatment effects than utilizing SPID to assess pain intensity.

PERSPECTIVE

The results of this meta-analysis suggest that TOTPAR may be more sensitive to treatment effects than SPIDs are in analgesic trials examining acute pain. We found that standardized effect sizes were higher for TOTPAR compared to SPIDs.