Pre-emptive analgesia

Acute Pain Management Following Mandibular Third Molar Exodontia: A Bibliometric Analysis of Randomized Controlled Trials

INTRODUCTION AND AIMS

To reveal the evolution of pain management strategies following mandibular third molar (M3M) exodontia, examine the geographic contribution of research, and explore future developments through a bibliometric analysis.

METHODS

A comprehensive search was conducted in various leading databases. Data on bibliometrics, participant demographics, and agent regimens were extracted for eligible studies. Descriptive bibliometrics, citation analysis, and keyword bursts were performed to assess the research outputs, distribution, and emerging hotspots.

RESULTS

A total of 173 randomized control trials from 2004 to 2024 were included. The number of publications showed a consistent upward trend since 2007. Brazil exhibited the most publications and citations. Germany presented the highest mean citations per publication. Brazil, Spain, and Italy showed the closest collaboration. Appropriately 14,391participants with 14,710 extracted M3M were enrolled. Nonsteroidal anti-inflammatory drugs (NSAIDs) were the most extensively studied analgesics, followed by glucocorticoids, opioids, and paracetamol. NSAIDs and paracetamol were predominantly administered orally, whereas glucocorticoids and opioids were primarily applied topically (P < .001). Studies on opioids significantly predated the studies using other agents. Adverse events were found in 50.87% of the included studies, where nausea and vomiting were the most frequently reported. Tramadol and piroxicam have drawn increasing interest in recent years.

CONCLUSIONS

This study revealed information on the research outputs, distribution, and future developments of analgesic agents following M3M exodontia. Brazil exhibited the highest level of productivity and recorded the most citations. NSAIDs generated the largest amount of research and are emerging as a benchmark for comparative studies. Oral administration is the most frequently used approach for agent delivery. Nausea and vomiting are the most commonly reported adverse effects.

CLINICAL RELEVANCE

The bibliometric analysis offers insights into the field of pain management following mandibular 3rd molar exodontia and how it has evolved. Tramadol and piroxicam have become research hotspots in recent years.

Harnessing artificial intelligence for predicting and managing postoperative pain: a narrative literature review

PURPOSE OF REVIEW

This review examines recent research on artificial intelligence focusing on machine learning (ML) models for predicting postoperative pain outcomes. We also identify technical, ethical, and practical hurdles that demand continued investigation and research.

RECENT FINDINGS

Current ML models leverage diverse datasets, algorithmic techniques, and validation methods to identify predictive biomarkers, risk factors, and phenotypic signatures associated with increased acute and chronic postoperative pain and persistent opioid use. ML models demonstrate satisfactory performance to predict pain outcomes and their prognostic trajectories, identify modifiable risk factors and at-risk patients who benefit from targeted pain management strategies, and show promise in pain prevention applications. However, further evidence is needed to evaluate the reliability, generalizability, effectiveness, and safety of ML-driven approaches before their integration into perioperative pain management practices.

SUMMARY

Artificial intelligence (AI) has the potential to enhance perioperative pain management by providing more accurate predictive models and personalized interventions. By leveraging ML algorithms, clinicians can better identify at-risk patients and tailor treatment strategies accordingly. However, successful implementation needs to address challenges in data quality, algorithmic complexity, and ethical and practical considerations. Future research should focus on validating AI-driven interventions in clinical practice and fostering interdisciplinary collaboration to advance perioperative care.

The efficacy of the ultrasound-guided retrolaminar block versus the classic paravertebral block in patients undergoing unilateral inguinal hernioplasty: a randomized controlled study

BACKGROUND

In daily surgical practice, inguinal hernioplasty is a frequent procedure that is frequently accompanied by severe postoperative pain. Multiple regional blocks have been described for analgesia after such operations. Retrolaminar block (RLB) is a paravertebral block (PVB) variant that provides excellent analgesia and reduces the risk of complications. This prospective trial compared the analgesic efficacy of PVB and RLB in the inguinal hernioplasty.

METHODS

The 56 patients included were randomly assigned into two equal groups according to the block performed under ultrasound guidance at the T12 level: PVB group (28 patients) and RLB (28 patients). Time until the first rescue analgesia was our primary outcome. Other outcomes included the time to perform the block, changes in intraoperative hemodynamic parameters, postoperative VAS, 24-h morphine consumption, the level of patient satisfaction, and the incidence of block-related complications.

RESULTS

Demographic data were comparable in the two groups. However, the time needed for the block was significantly shortened with the RLB (p < 0.001). Patients in the PVB groups expressed better pain scores and lower opioid consumption. Additionally, the time to the first call for opioid analgesia showed a significant prolongation in association with the PVB. There was no discernible difference in the frequency of adverse events and recorded MAP and HR.

CONCLUSION

The PVB has a superior perioperative analgesic profile compared to the RLB, which manifested in the prolonged duration to the first rescue analgesics, better pain scores, and less opioid consumption, with no significant increase in block-related complications.

Pre-Emptive Acetaminophen for Postoperative Pain (PAPP): An Updated Meta-Analysis

PURPOSE

Postoperative pain is a common consequence of surgery. Pre-emptive analgesia involves the initiation of analgesics prior to surgical incision. This has been proposed as a simple method to help reduce postoperative pain, which may be more effective in higher-risk populations such as cervical spine surgery. A previous meta-analysis has demonstrated that pre-emptive acetaminophen may be effective in reducing postoperative pain although the certainty of evidence was limited. This present paper is an updated meta-analysis comparing pre-emptive acetaminophen versus postincision acetaminophen in adult patients undergoing surgery.

DESIGN

Systematic review and meta-analysis with the inclusion of an unpublished randomized, placebo-controlled, double-blind trial.

METHODS

An updated meta-analysis was conducted which searched electronic databases to identify randomized controlled trials with the same interventions.

FINDINGS

We included 845 participants and 12 studies in the updated meta-analysis. The meta-analysis (including our trial) found reduced 24-hour morphine consumption in the pre-emptive group (mean difference -2.42 mg; 95% confidence interval -4.26 to -0.59 mg), as well as reduced postoperative vomiting (risk ratio 0.56; 95% confidence interval 0.36 to 0.88). There was no difference between pre-emptive acetaminophen and control groups for time to analgesic request, pain scores at 6 and 24 hours or pruritis. For all outcomes assessed, there was very low certainty of evidence.

CONCLUSIONS

This meta-analysis found pre-emptive acetaminophen reduced 24-hour opioid consumption and postoperative vomiting.

Pudendal Block at the Time of Transvaginal Prolapse Repair: A Randomized Controlled Trial

IMPORTANCE

The utility of pudendal nerve blocks (PNBs) at the time of transvaginal surgery is mixed in the literature. No published study has evaluated the efficacy of PNB since the widespread adoption of Enhanced Recovery After Surgery (ERAS) pathways.

OBJECTIVE

This study aimed to determine if PNB, in addition to ERAS measures, at the time of vaginal reconstructive surgery reduces opioid use in the immediate postoperative period.

STUDY DESIGN

In this randomized, blinded, controlled trial, women scheduled for transvaginal multicompartment prolapse repair were randomized to bilateral PNB before incision with 20 mL of 0.5% bupivacaine versus usual care. Primary outcome was opioid use in morphine milligram equivalents (MME) for the first 24 hours. The study was powered to detect a 5.57-MME difference in opioid use in the first 24 hours between groups.

RESULTS

Forty-four patients were randomized from January 2020 to April 2022. The PNB and control groups were well matched in demographic and surgical data. There was no difference in opioid use in first 24 hours between the control and PNB groups (8 [0-20] vs 6.7 [0-15]; P = 0.8). Median pain scores at 24 and 48 hours did not differ between groups (4 ± 2 vs 3 ± 3; P = 0.44) and 90% of participants were satisfied with pain control across both groups. Time to return to normal activities (median, 10 days) was also not different between the groups.

CONCLUSIONS

Because pain satisfaction after transvaginal surgery in the era of ERAS is high, with overall low opioid requirements, PNB provides no additional benefit.

Quadratus lumborum block versus transversus abdominis plane block for inguinal hernia repair: A systematic review and meta-analysis with trial sequential analysis

INTRODUCTION

Postoperative pain management is crucial for patient recovery with Quadratus Lumborum Block (QLB) and Transversus Abdominis Plane Block (TAPB) emerging as potential techniques. We aimed to compare the analgesic efficacy of QLB and TAPB in patients undergoing inguinal hernia repair.

METHODS

We performed a systematic review of Cochrane, EMBASE, and MEDLINE databases to identify randomized controlled trials comparing QLB and TAPB in patients undergoing inguinal hernia repair. Outcomes included postoperative pain and opioid consumption. Statistical analysis was performed using RevMan 5.4. The review protocol was registered at PROSPERO (CRD42023445513).

RESULTS

We included five RCTs encompassing 255 patients. QLB was associated with a significant decrease in postoperative pain (MD -0.45; 95% CI -0.75 to -0.14; and p = 0.004; I2  = 94%). However, we found no difference in 24-h opioid consumption between QLB and TAPB groups.

CONCLUSION

QLB may offer superior pain reduction. However, its effect on opioid consumption remains unclear.

Regional Anesthesia Is Safe and Effective for Low-Energy Tibial Plateau Fractures

The purpose of this study was to determine if the use of peripheral nerve blocks in the operative management of tibial plateau fractures is associated with improved outcomes when compared with the use of spinal and general anesthesia. Over a period of 16 years, 132 patients who underwent operative repair for a low-energy tibial plateau fracture and had at least 12 months of follow-up met the inclusion criteria and formed the basis of this study. Patients were grouped into cohorts based on the anesthetic method used during surgery: peripheral nerve block in combination with conscious sedation or general anesthesia (BA), general anesthesia alone (GA), or spinal anesthesia alone (SA). Outcomes were assessed at 3 months, 6 months, and 12 months. Length of stay was greatest in the GA cohort (P<.05), and more patients in the BA cohort were discharged to home (P<.05). Patients in the GA cohort had the highest pain scores at 3 months and 6 months (P<.05). Patients in both the SA and BA cohorts had better Short Musculoskeletal Function Assessment scores at 6 and 12 months when compared with the GA cohort (P<.05). Although knee range of motion did not differ among the three cohorts at 3 months, it did differ at 6 months and 12 months postoperatively, with those who had a preoperative nerve blockade (SA and BA) having the greatest knee range of motion (P<.05). Regional anesthesia was safe and was associated with lower pain scores in the early postoperative period and greater knee range of motion and functional outcome scores in the late postoperative period. [Orthopedics. 2023;46(6):358-364.].

Multimodal intrathecal analgesia (MITA) with morphine for reducing postoperative opioid use and acute pain following hepato-pancreato-biliary surgery: A multicenter retrospective study

INTRODUCTION

The optimal analgesic modality for patients undergoing hepato-pancreato-biliary (HPB) surgery remains unknown. The analgesic effects of a multimodal intrathecal analgesia (MITA) technique of intrathecal morphine (ITM) in combination with clonidine and bupivacaine compared to ITM alone have not been investigated in these patients.

METHODS

We performed a multicenter retrospective study of patients undergoing complex HPB surgery who received ITM, bupivacaine, and clonidine (MITA group) or ITM-only (ITM group) as part of their perioperative analgesia strategy. The primary outcome was the unadjusted oral morphine equivalent daily dose (oMEDD) in milligrams on postoperative day 1. After adjusting for age, body mass index, hospital allocation, type of surgery, operation length, and intraoperative opioid use, postoperative oMEDD use was investigated using a bootstrapped quantile regression model. Other prespecified outcomes included postoperative pain scores, opioid-related adverse events, major complications, and length of hospital stay.

RESULTS

In total, 118 patients received MITA and 155 patients received ITM-only. The median (IQR) cumulative oMEDD use on postoperative day 1 was 20.5 mg (8.6:31.0) in the MITA group and 52.1 mg (18.0:107.0) in the ITM group (P < 0.001). There was a variation in the magnitude of the difference in oMEDD use between the groups for different quartiles. For the MITA group, on postoperative day 1, patients in the 25th percentile required 14.0 mg less oMEDD (95% CI: -25.9 to -2.2; P = 0.025), patients in the 50th percentile required 27.8 mg less oMEDD (95% CI: -49.7 to -6.0; P = 0.005), and patients in the 75th percentile required 38.7 mg less oMEDD (95% CI: -72.2 to -5.1; P = 0.041) compared to patients in the same percentile of the ITM group. Patients in the MITA group had significantly lower pain scores in the postoperative recovery unit and on postoperative days 1 to 3. The incidence of postoperative respiratory depression was low (<1.5%) and similar between groups. Patients in the MITA group had a significantly higher incidence of postoperative hypotension requiring vasopressor support. However, no significant differences were observed in major postoperative complications, or the length of hospital stay.

CONCLUSION

In patients undergoing complex HPB surgery, the use of MITA, consisting of ITM in combination with intrathecal clonidine and bupivacaine, was associated with reduced postoperative opioid use and resulted in superior postoperative analgesia without risk of respiratory depression when compared to patients who received ITM alone. A randomized prospective clinical trial investigating these two intrathecal analgesic techniques is justified.

Rhomboid intercostal block versus serratus block for postoperative analgesia after thoracoscopic sympathectomy for primary palmar hyperhidrosis: a randomized controlled trial

BACKGROUND

Although thoracoscopic sympathectomy is made via small incisions, it is associated with severe postoperative pain. Both Rhomboid intercostal block (RIB) and serratus anterior plane block (SABP) are recent techniques used for pain control after such procedures. Herein, we compared RIB and SAPB regarding pain control in patients undergoing thoracoscopic sympathectomy for palmar hyperhidrosis.

PATIENTS AND METHODS

Three groups were enrolled in this prospective randomized study (71 patients in each group); Group S received SAPB, Group R received RIB and Group C as controls. The block procedures were performed after general anesthesia and prior to the skin incision.

RESULTS

The three groups showed comparable demographics and operative time (P ˃ 0.05). Pain scores showed a significant decline with the two block procedures compared to controls during the first day following surgery (both P ˂ 0.05), but Group R had better scores compared to Group S. Both block techniques were associated with a significant prolongation of the time to first rescue analgesic and less fentanyl consumption compared to controls (both P ˂ 0.05). However, both parameters were improved with RIB rather than SAPB (both P ˂ 0.05). Both blocks led to a significant improvement in patient satisfaction than in the control group (both P ˂ 0.05), but it was comparable between the two approaches (P ˃ 0.05).

CONCLUSION

Both RIB and SAPB are safe and effective in pain reduction after thoracoscopic sympathectomy procedures in patients with hyperhidrosis. Moreover, RIB is superior to SAPB as it is associated with better analgesic outcomes.

TRIAL REGISTRATION

Pan African Trial Registry PACTR202203766891354. https://pactr.samrc.ac.za/Researcher/TrialRegister.aspx?TrialID=21522.

Efficacy of Lornoxicam as a Pre-emptive Analgesic in Mandibular Third Molar Surgery - A Comparative Study

Introduction

The most common complication following third molar surgery is pain. The purpose of the study is to determine the efficacy of lornoxicam as a preventive analgesic in patients undergoing surgical removal of impacted mandibular third molars.

Materials and Methods

This study included 26 participants aged 18-28 years with bilateral symmetrical third molars. Group A, the control group, received lornoxicam 8 mg 1 h after surgery, whereas Group B, the study group, received lornoxicam 8 mg 1 h before surgery. All patients were evaluated for pain at the 1st, 2nd, 4th, 6th, 8th and 12th post-operative hours. The number of rescue analgesics taken within 24 h of the procedure, as well as the first occurrence of pain postoperatively, was recorded and analysed.

Results

Using the Mann-Whitney U-test and Friedman's analysis, the resulting data were statistically analysed. When Group B was compared to Group A, there was a significant difference in pain reduction levels in the immediate post-operative hours. When compared to Group A, Group B had a lower need for rescue analgesics within the first 24 h postoperatively.

Discussion

Following mandibular third molar surgery, pre-emptive use of lornoxicam is effective in reducing post-operative pain and reducing the need for rescue analgesic consumption.

Modulation of the Inflammatory Response by Pre-emptive Administration of IMT504 Reduces Postoperative Pain in Rats and has Opioid-Sparing Effects

Despite the available knowledge on underlying mechanisms and the development of several therapeutic strategies, optimal management of postoperative pain remains challenging. This preclinical study hypothesizes that, by promoting an anti-inflammatory scenario, pre-emptive administration of IMT504, a noncoding, non-CpG oligodeoxynucleotide with immune modulating properties, will reduce postincisional pain, also facilitating therapeutic opioid-sparing. Male adult Sprague-Dawley rats with unilateral hindpaw skin-muscle incision received pre-emptive (48 and 24 hours prior to surgery) or postoperative (6 hours after surgery) subcutaneous vehicle (saline) or IMT504. Various groups of rats were prepared for pain-like behavior analyses, including subgroups receiving morphine or naloxone, as well as for flow-cytometry or quantitative RT-PCR analyses of the spleen and hindpaws (for analysis of inflammatory phenotype). Compared to vehicle-treated rats, pre-emptive IMT504 significantly reduced mechanical allodynia by 6 hours after surgery, and accelerated recovery of basal responses from 72 hours after surgery and onwards. Cold allodynia was also reduced by IMT504. Postoperative administration of IMT504 resulted in similar positive effects on pain-like behavior. In IMT504-treated rats, 3 mg/kg morphine resulted in comparable blockade of mechanical allodynia as observed in vehicle-treated rats receiving 10 mg/kg morphine. IMT504 significantly increased hindpaw infiltration of mesenchymal stem cells, CD4+T and B cells, and caused upregulated or downregulated transcript expressions of interleukin-10 and interleukin-1β, respectively. Also, IMT504 treatment targeted the spleen, with upregulated or downregulated transcript expressions, 6 hours after incision, of interleukin-10 and interleukin-1β, respectively. Altogether, pre-emptive or postoperative IMT504 provides protection against postincisional pain, through participation of significant immunomodulatory actions, and exhibiting opioid-sparing effects. PERSPECTIVE: This preclinical study introduces the noncoding non-CpG oligodeoxynucleotide IMT504 as a novel modulator of postoperative pain and underlying inflammatory events. The opioid-sparing effects observed for IMT504 appear as a key feature that could contribute, in the future, to reducing opioid-related adverse events in patients undergoing surgical intervention.

Narcotic Requirements before and after Implementation of Buccal Nerve Blocks for Buccal Mucosa Graft Harvest: Technique and Retrospective Review

The reduction in opioid use has become a public health priority. We aimed to assess if performing buccal nerve blocks (BNB) at the time of buccal mucosa graft (BMG) harvest impacts post-operative narcotic usage in the inpatient setting. We retrospectively reviewed clinical characteristics and morphine milligram equivalents (MMEs) received for all patients that underwent a BMG urethroplasty at our institution. The primary outcome measure was post-operative MMEs for patients before and after implementing the BNB. We identified 74 patients that underwent BMG urethroplasty, 37 of which were before the implementation of the BNB and 37 of which were after. No other changes were made to the peri-operative pathway between these time points. The mean total MMEs per day, needed post-operatively, was lower in the BNB group (8.8 vs. 5.0, p = 0.12). A histogram distribution of the two groups, categorized by number of MMEs received, showed no significant differences between the two groups. In this retrospective analysis, we report our experience using BNBs at the time of buccal mucosa graft harvest. While there were no significant differences between the number of MMEs received before and after implementation, further research is needed to assess the blocks’ impact on pain scores.

Implementation of enhanced recovery in cardiac surgery: An experimental study with the control group

INTRODUCTION

The Enhanced Recovery After Cardiac Surgery protocol is the most recent addition to cardiac treatment. In this paper, we aimed to test the safety and viability of this protocol in our hospital to improve our standard of care.

METHODS

This study was conducted as an experimental study with a historical control at the Maritime Heart Center, Halifax, Nova Scotia, Canada. In order to quantify the success of this protocol, we measured the postoperative Length of Hospital Stay and three intensive care unit variables: time to extubation, time to ambulation, and opioid consumption. In the study, 100 patients were in the Enhanced Recovery After Cardiac Surgery group, and 103 patients were used as historic controls-selected by strenuous chart review and selection criteria.

RESULTS

The primary outcome (Length of Hospital Stay) was reduced from a mean of 8.88 ± 3.50 days in the control group to a mean of 5.13 ± 1.34 days in the Enhanced Recovery After Cardiac Surgery group (p < 0.001). Likewise, we observed a significant reduction in intensive care unit variables: time to extubation was reduced from 10.54 ± 7.83 h in the control group to 6.69 ± 1.63 in the Enhanced Recovery After Cardiac Surgery group (p < 0.01), and time to ambulation was reduced from 36.27 ± 35.21 h in the control group to 9.78 ± 2.03 in the Enhanced Recovery After Cardiac Surgery group (p < 0.01) and opioid consumption was reduced from 50.58 ± 11.93 milligram morphine equivalent in the control group to 11.58 ± 4.43 milligram morphine equivalent in the Enhanced Recovery After Cardiac Surgery group (p < 0.01).

CONCLUSION

Enhanced Recovery After Cardiac Surgery protocols were seamlessly integrated into selected cardiac surgical patients, contingent on a high level of interprofessional communication and collaboration.

Early perioperative versus postoperative meloxicam for pain control in patients undergoing orthopedic surgery: a systematic review and Meta-analysis of randomized controlled trials

OBJECTIVE

Post-orthopaedic operative pain is a serious concern that often requires the administration of analgesics; however, the optimal time of analgesic administration is still inconclusive. Perioperative analgesia is administrating pre-emptive analgesia before and during the surgery followed by postoperative analgesia to decrease the procedure associated nociceptive response. We aim to assess perioperative meloxicam versus postoperative meloxicam for pain control after orthopaedic operations.

METHODS

A systematic review and meta-analysis involving randomized controlled trials from PubMed, Embase, Scopus, WOS, and Cochrane until 28th May 2022. We pooled dichotomous outcomes using risk ratio (RR) presented with a 95% confidence interval (CI) and continuous outcomes using mean difference (MD) with 95% CI. We registered our protocol in PROSPERO with ID: CRD42022336046.

RESULTS

We included five RCTs with 964 patients. All the included trials showed high risk of performance and detection biases because of lack of blinding. Pooled analysis favored perioperative meloxicam in reducing pain score after six hours (MD: -0.42 with 95% CI [-0.63, -0.21], p = .0001), 12 h (MD: -0.54 with 95% CI [-0.69, -0.39], p = .00001), and 24 h (MD: -0.23 with 95% CI [-0.36, -0.10]. Pooled analysis favored perioperative meloxicam in improving patient global assessment scale after 12 h (MD: -0.66 with 95% CI [-0.86, -0.46], p = .00001), 24 h (MD: -0.30 with 95% CI [-0.49, -0.11, p = .002), and 48 h (MD: -0.17 with 95% CI [-0.33, -0.01], p = .04). Pooled analysis favored perioperative meloxicam in reducing patient-controlled analgesia (MD: -4.25 with 95% CI [-5.96, -2.54], p = .00001).

CONCLUSION

Short-term pain management after orthopaedic procedures is better accomplished with perioperative meloxicam than postoperative meloxicam. Before recommending perioperative meloxicam for pain control following orthopaedic surgeries, further multicentre trials are still warranted to examine the impact of perioperative meloxicam in different orthopaedic procedures.

Transversus abdominus plane blocks do not reduce rates of postoperative prolonged opioid use following abdominally based autologous breast reconstruction: a nationwide longitudinal analysis

Background

The transversus abdominus plane (TAP) block reduces postoperative donor site pain in patients undergoing autologous breast reconstruction with an abdominally based flap. This study aimed to determine the effect of TAP blocks on rates of conversion to chronic opioid use.

Methods

The Clinformatics Data Mart was queried from 2003 to 2019, extracting adult encounters for abdominally based free and pedicled flaps based on common procedural terminology (CPT) codes. Patients were excluded if they had filled a narcotic prescription 1 year to 30 days prior to surgery. The exposure variable-TAP block-was identified by CPT codes. Outcomes were evaluated using morphine milligram equivalents (MME) from prescriptions filled between 30 days prior to and 30 days after surgery. Chronic opioid use (COU) was defined as receiving 4 unique prescriptions or a 60-day supply between 30 and 180 days after surgery.

Results

Of the 4091 patients, (mean age 51.2 ± 9.0 years), 181 (4.4%) had a TAP block placed. Perioperative MMEs/day, postoperative COU, and length of stay did not differ in patients who received a TAP block (p = 0.142; p = 0.271). Significant predictors of risk of conversion to COU included younger age, pedicled abdominal flap, Elixhauser comorbidity index score > 3, filling a psychiatric medication prescription, and filling a benzodiazepine prescription.

Conclusions

In patients undergoing autologous breast reconstruction with abdominally based flap reconstruction, TAP blocks do not decrease perioperative MME/day, conversion to chronic opioid use, or length of stay. These data suggest that intraoperative TAP block placement may be a low-yield opioid-reduction strategy.Level of evidence: Level III, risk/prognostic study.

The Effect of Pre-emptive Oral Melatonin versus Placebo on Post-operative Analgesia in Infants after Thoracotomy for Closed Cardiac Surgeries: A Randomized Controlled Study

BACKGROUND: Thoracotomy pain is one of the severest types of pain that should be managed properly, especially in children. Opioids are the most widely prescribed analgesics for post-operative pain, but they can have a number of undesirable side effects. Melatonin could be employed as an adjuvant analgesic therapy during procedural discomfort as it had no known major side effects. STUDY DESIGN: This was a double-blinded, controlled randomized study. METHODS: Fifty patients divided randomly into two equal groups. One hour before surgery, children in M group (n = 25) were given 0.5 mg/kg orally of melatonin 3 mg tablets) and patients in Group P (n = 25) received a placebo (5 ml of water by syringe 5 ml) orally. Post-operative pethidine consumption over the 1st 24 h (mg) was recorded, the intraoperative fentanyl consumption (HR and ABP) at baseline, 1 min after induction, at skin incision, and every 30 min till the end of the surgery were recorded. Neonatal Infant Pain Score (NIPS) at 4 h, 6 h, 8 h, 12 h, 18 h, and 24 h postoperatively was recorded. Other reported data include demographic data, extubation time, days of ICU stay, and complications. RESULTS: Total post-operative pethidine consumption (mg) over 24 h was significantly lower in M group than P group (3.48 ± 2.23 vs. 7.68 ± 4.52 p = 0.01). Intraoperative fentanyl consumption (ug) was significantly lower in M group than P group (10.28 ± 4.98 vs. 17.08 ± 7.39 p < 0.001). As regards NIPS, it was statistically lower in M group than P group in all times except at 8 h and 24 h with significant difference. CONCLUSION: Oral melatonin is an effective and safe pre-emptive drug as it reduces the total post-operative pethidine consumption over the first 24 h and decreased post-operative pain scores without any unpleasant effects in pediatrics undergoing closed heart surgery.

Pharmacokinetics of metamizole (dipyrone) as an add-on in calves undergoing umbilical surgery

This preliminary clinical investigation of the pharmacokinetic behavior of the main metamizole (dipyrone) metabolites 4-methylaminoantipyrine (4-MAA) and 4-aminoantipyrine (4-AA) in calves undergoing umbilical surgery is part of an already published main study. A single intravenous dose of metamizole was added to ketamine/xylazine/isoflurane anesthesia. Eight Simmental calves weighing 90 ± 10.8 kg and aged 47.6 ± 10.4 days received 40 mg/kg metamizole intravenously 10 minutes prior to general anesthesia. Blood samples were collected over 24 hours and analyzed for 4-MAA and 4-AA. Meloxicam was additionally given twice: 2.5 hours pre- and 20.5 hours postsurgically. The pharmacokinetic profile of 4-MAA was best fitted to a two-compartment model and was characterized by a fast distribution half-life and slow elimination half-life (t_½alpha = 5.29 minutes, t_½beta = 9.49 hours). The maximum concentration (C_max 101.63 μg/mL) was detected at the first measurement time point 15 minutes after administration. In contrast, 4-AA showed fast, high and biphasic plasma peak concentration behavior in five calves (2.54–2.66 μg/mL after 15–30 minutes, and 2.10–2.14 μg/mL after 2–3.5 hours) with a t_½beta of 8.87 hours, indicating a rapid distribution and subsequent redistribution from well-perfused organs. Alternatively, three calves exhibited a slower and lower monophasic plasma peak concentration (1.66 μg/mL after 6.5 hours) with a t_½beta of 6.23 hours, indicating slow accumulation in the intravascular compartment. The maximum concentration and area under the plasma concentration curve (AUC) of 4-AA were lower than those of 4-MAA. This metabolic behavior supports our already published data on clinical monitoring and plasma cortisol concentrations (PCCs). Compared to those of saline controls, lower PCCs correspond to the t_½alpha of 4-MAA. Data on T_max and t_½beta also match these clinical observations. However, further studies are required to assess the exact analgesic mechanism and potency of the metamizole metabolites in calves.

The effect of pre-emptive ibuprofen on post-operative pain after removal of lower third molar teeth: a systematic review

Objective To investigate the effect of pre-emptive ibuprofen on post-operative pain after lower third molar surgery.Methods A search for randomised controlled trials was undertaken across the databases Medline, Embase, Cochrane Central and Dentistry and Oral Sciences Source. Citation searching was used to supplement the database search. Inclusion and exclusion criteria were used for independent double screening by two assessors.Results A total of five randomised controlled trials were included in the review. A risk of bias assessment identified some concerns in four of the included studies. One study was assessed as having low risk of bias. The important outcomes measured were post-operative pain intensity, total pain relief, use of rescue analgesia, time to rescue analgesia and total consumption of rescue analgesia. In two trials, pre-emptive ibuprofen was shown to significantly reduce pain intensity after lower third molar surgery compared with placebo. Two trials showed no significant difference between ibuprofen and placebo groups. Pre-emptive ibuprofen was shown to provide superior pain relief compared with placebo in the one trial measuring this outcome. Where the use of rescue medication was measured as an outcome, two trials showed that pre-emptive ibuprofen was superior to placebo, one trial showed that placebo was superior to ibuprofen and two trials found no significant difference between ibuprofen and placebo groups.Conclusion Due to the inconsistency of the results, there is insufficient evidence to support the use of pre-emptive ibuprofen for management of post-operative pain after lower third molar surgery. Further research into the effects of pre-emptive analgesia on the surgical pain pathway is required.

COMPARATIVE ANALGESIC EFFECTS OF SINGLE-DOSE PREOPERATIVE ADMINISTRATION OF PARACETAMOL (ACETAMINOPHEN) 500 mg PLUS CODEINE 30 mg AND IBUPROFEN 400 mg ON PAIN AFTER THIRD MOLAR SURGERY

BACKGROUND

Efficacy and rapid onset of postsurgical oral pain relief are critical to improve clinical outcomes and reduce the risk of excessive dosing with analgesic drugs.

PURPOSE

To compare analgesic effects of preoperative administration of paracetamol 500 mg plus codeine 30 mg in single-tablet and effervescent formulation to ibuprofen 400 mg, and placebo in the management of moderate to severe postoperative pain after mandibular third molar surgery.

MATERIALS AND METHODS

One hundred twenty healthy outpatients aged 15-29 years undergoing surgical removal of 1 bony impacted mandibular third molar were enrolled in this, single-center, prospective, randomized, triple-blind parallel-group, placebo-controlled, clinical trial. Study participants were randomly assigned to three treatment arms. According to the concealed allocation, each patient 30 minutes before surgery received paracetamol 500 mg plus codeine 30 mg (group APAP/COD), ibuprofen 400 mg (group IBU) or placebo (group PLA). Rescue therapy allowed in the postoperative period was paracetamol 500 mg plus codeine 30 mg in groups APAP/COD and PLA and ibuprofen 400 mg in group IBU. Patients recorded on Numerical Rating Scale-11 (NRS-11) the pain intensity, total number of postoperative-supplement medications and time of the first intake, until 12-hours after surgery and over extra 2 days, RESULTS: Over postoperative 3 days, patients in the APAP/COD group (2.33 ± 1.99) displayed significantly (P< .001) less pain intensity than IBU (3.43 ± 2.47) and placebo (3.57 ± 2.62) groups. The first-day postoperative pain was significantly (P < .001) higher in group PLA than in groups APAP/COD and IBU, but not between the latter 2 groups. However, at 2 hours postdose, the IBU group displayed average pain intensity lower than APAP/COD group (P> .05). On the next 2 days, pain intensity was significantly (P< .001) lower in group APAP/COD than in groups IBU and PLA but failed to reach statistical significance between groups IBU and PLA. Although the time to the first using rescue therapy was longer (445.88 ± 159.96 minute) in group IBU, compared to groups APAP/COD (392.67 ± 138.90 minutes) and PLA (323.00 ± 143.95 minutes), the number of supplemented tablets was significantly higher in group IBU (2.89 ± 2.13) than in groups APAP/COD (1.24 ± 1.79) (P= .001) and PLA (1.53 ± 1.67) (P = .008). No adverse events were registered for all groups.

CONCLUSIONS

Within the limits of the present study, over postoperative 3 days, a statistically significant intensity pain reduction and decreased rescue therapy consumption were recorded in the paracetamol-codeine group than to ibuprofen group. Nevertheless, lower pain intensity at 2 hours postdose and longer time using rescue therapy was found in the ibuprofen group without statistical significance. No adverse events occurred over the studied period.

A comparison of preincisional and postincisional ultrasound guided transversus abdominis plane block

Background and Aims:

Transversus abdominis plane blocks are part of the multimodal analgesia used for lower abdominal surgeries.Our aim of this study was to compare the analgesic efficacy of preincisional and postincisional TAP blocks in patients undergoing total abdominal hysterectomies.

Material and Methods:

54 American Society of Anesthesiologists physical status I and II patients aged between 30 and 60 years who underwent a total abdominal hysterectomy under spinal anesthesia in our hospital were chosen for the study. Alternate patients satisfying the inclusion criteria were either given a preincisional or postincisional transversus abdominis plane block bilaterally. Postoperatively, the numeric pain intensity scale was observed, along with nausea, vomiting, and sedation scores.

Results:

Pain scores were significantly lower (P < 0.05) in the preincisional TAP block group from the 2^nd postoperative hour onwards till 12 h, and thereafter it was comparable between both the groups. The total morphine requirement was significantly less in the preincisional TAP group (P-value 0.001). Also, the mean time to the first request for morphine was significantly longer in patients belonging to the preincisional TAP block group (P-value of 0.002). There were no significant differences in the sedation scores postoperatively, except at the 4^th hour, where it was significantly higher (P-value of 0.024) in the postincisional TAP group. Post operative nausea and vomiting was significantly higher and so the dose of the antiemetic used was also observed to be more in the postincisional TAP block group.

Conclusion:

Preincisional TAP blocks are more effective than postincisional ones with better analgesia and lesser side effects, for total abdominal hysterectomies.

Effects of ibuprofen administration timing on oral surgery pain: A randomized clinical trial

OBJECTIVE

This study aimed to compare the analgesic effect of ibuprofen 400 mg given 30 min before or immediately after third molars surgery under local anaesthesia.

MATERIALS AND METHODS

The single-centre, randomized, split-mouth, triple-blind, clinical trial involved 38 outpatients, for a total of 76 bilateral symmetrical fully bone impacted mandibular third molars. Each patient was undergone to separate surgical sessions for the right and left side, and ibuprofen was randomly administered 30 min before or immediately after the intervention. Study participants recorded pain intensity using Numerical Rating Scale-11, the timing of rescue therapy intake and overall tablets consumption over 3 days.

RESULTS

The overall pain intensity score was lower in the group receiving ibuprofen immediately after (3.13 ± 2.46) than before (3.58 ± 2.40) surgery, with statistically significant differences only on the second and third days. The mean time to the first using rescue therapy was longer in the postoperative (598.33 ± 422.62 min) than in the preoperative (406.25 ± 149.79 min) analgesic treatment group (p = .123). The number of supplemented ibuprofen tablets did not differ (p = .530) between both groups.

CONCLUSIONS

Within the limits of the present study, ibuprofen administration immediately after surgery seemed to be more effective than preoperative administration.

Liposomes for Intra-Articular Analgesic Drug Delivery in Orthopedics: State-of-Art and Future Perspectives. Insights from a Systematic Mini-Review of the Literature

Background and objectives: Liposomal structures are artificial vesicles composed of one or several lamellae of phospholipids which surround an inner aqueous core. Given the amphoteric nature of phospholipids, liposomes are promising systems for drug delivery. The present review provides an updated synthesis of the main techniques for the production of liposomes for orthopedic applications, focusing on the drawbacks of the conventional methods and on the advantages of high pressure techniques. Materials and Methods: Articles published in any language were systematically retrieved from two major electronic scholarly databases (PubMed/MEDLINE and Scopus) up to March 2020. Nine articles were retained based on the “Preferred Reporting Items for Systematic Reviews and Meta-Analyses” (PRISMA) guidelines. Results: Liposome vesicles decrease the rate of inflammatory reactions after local injections, and significantly enhance the clinical effectiveness of anti-inflammatory agents providing controlled drug release, reducing toxic side effects. Conclusions: This review presents an update on the improvement in musculoskeletal ailments using liposome treatment.

Comparative Evaluation of Preemptive Analgesia of Dextromethorphan and Ibuprofen in Third Molar Surgeries

Introduction:

Postoperative pain following third molar removal is one of the most common and unpleasant complications encountered in routine surgical practice. Various methods have been advocated to minimize the postoperative pain: preemptive analgesia is one of those found to be effective.

Objective:

The aim of this study was to compare the preemptive analgesic efficacy of Dextromethorphan (DM) and Ibuprofen in the third molar surgeries.

Material and Methods:

Thirty-six patients reporting to our institution were included in the study. Patients were randomized into three groups of 12 patients each to receive either DM 30 mg, ibuprofen 100 mg, or placebo in the form of multivitamin syrup, 90 min before the procedure. The difficulty of removal of the teeth was assessed using Campbell difficulty score. The study objectives were to evaluate the time elapsed since surgery after which the patient took their first dose of aceclofenac, to evaluate the postoperative pain using visual analog scale score, and to record the number of aceclofenac tablets consumed postoperatively.

Results:

The results of the study revealed that preemptive DM was significantly better than ibuprofen and placebo in the duration of time that elapsed before the patients consumed their first analgesic postoperatively. Preemptive DM also reduced the total number of aceclofenac tablets consumed on the day of surgery and on the 1^st postoperative day, but the difference was not statistically significant. Between the two drugs, DM is better suited for providing preemptive analgesia. No side effects at a dose of 30 mg of DM were noted in any of the patients.

Conclusion:

DM premedication is a viable preemptive analgesic in reducing postoperative pain.

Comparison of preincisional and postincisional parasternal intercostal block on postoperative pain in cardiac surgery

BACKGROUND

The optimum cardiac surgical pain management has known to maintain hemodynamic stability and, reduces respiratory and cardiovascular complications. Postoperative parasternal intercostal block has shown to reduce postoperative analgesic consumption after cardiac surgery. Therefore, this study sought to investigate the effectiveness of the preoperative ultrasound guided parasternal block in reducing postoperative pain after cardiac surgery.

METHODS

This was a randomized, prospective, interventional, single blind study comprised of 90 adult patients scheduled for cardiac surgery involving sternotomy. Preoperatively and postoperatively, 0.25% bupivacaine administered in 4 mL aliquots into the anterior (2nd-6th) intercostal spaces on each side about 2 cm lateral to the sternal edge with a total volume of 40 mL under ultrasound guidance and direct vision, respectively. Postoperative pain was rated according to visual analogue scale. Secondary outcomes included intraoperative and postoperative fentanyl consumptions, dosages of rescue medications, and time to extubation.

MAIN RESULTS

There was no significant differences in visual analogue score visual analogue score at all time points till 24 hours postoperatively. Intraoperative fentanyl requirements (microgram/kg) before cardiopulmonary bypass was significantly lower in pre-incisional group than the post-incisional group (0.16 ± 0.43 vs 0.68 ± 0.72; P = .0001). Furthermore, there were no significant difference in total fentanyl requirement (7.20 ± 2.66 vs 8.37 ± 3.13; P = .06) and tramadol requirement (0.02 ± 0.15 vs 0.07 ± 0.26; P = .28) within first 24 hours. However, time to extubation was significantly higher in the preoperative group (P = .02).

CONCLUSIONS

Preoperative and postoperative parasternal intercostal block provide comparable pain relief during the postoperative period.

The effects of flunixin meglumine and hoof trimming on lying behavior, locomotion, and milk production in lame and nonlame lactating dairy cows

Hoof trimming is used to prevent and treat lameness in dairy cows; however, hoof trimming itself increases daily time spent lying down, possibly due to discomfort. We hypothesized that treatment of lame and nonlame cows with an anti-inflammatory analgesic drug at the time of hoof trimming would mitigate discomfort, thereby improving locomotion scores and reducing post-trimming increases in lying time. We further hypothesized that drug treatment would improve post-trimming milk production. Our objective was to determine the effects of treatment with the nonsteroidal anti-inflammatory drug flunixin meglumine (2.2 mg/kg of BW) at the time of hoof trimming on locomotion, lying times, and milk production in lame and nonlame lactating dairy cows. All cows were filmed for locomotion scoring 1 d before and 1, 8, and 28 d after hoof trimming. Daily time spent standing and lying was recorded for 4 d before and 4 wk after hoof trimming, and daily milk production was recorded for 1 wk before and 8 wk after trimming. Thirty minutes before hoof trimming, an intravenous injection of flunixin meglumine (n = 34) or isotonic sterile saline solution (n = 34) was administered to each cow. Then, all cows had their hooves trimmed using the Dutch method. The same treatment was repeated 24 h after hoof trimming. Cows were categorized using baseline locomotion scores as lame (score ≥3/5) or nonlame (score <3/5). Drug treatment did not affect post-trimming changes in locomotion scores, daily lying times, or milk production. In both treatment groups, most cows had the same lameness status (lame or nonlame) at baseline and after treatment, and there was no difference between groups in the number of cows that changed lameness status over time. Lame cows (n = 21) had no significant changes in lying times over the course of the study, whereas nonlame cows (n = 47) had mean daily lying times that were significantly higher than baseline all 4 wk after trimming. Hoof trimming in nonlame cows should be scheduled for a time when increased lying behavior after trimming can be accommodated.

Comparison of the effects of preoperative melatonin or vitamin C administration on postoperative analgesia

The analgesic benefit of melatonin and vitamin C as primary or adjuvant agents has been reported in various studies; however, their analgesic effects in the treatment of postoperative pain remain unclear. Thus, we aimed to evaluate the effect of single preoperative dose of oral melatonin or vitamin C administration on postoperative analgesia. In this study, we recruited 165 adult patients undergoing elective major abdominal surgery under general anesthesia. Patients were randomly divided into three equal (n = 55) groups. One hour before surgery, patients received orally melatonin (6 mg) in group M, vitamin C (2 g) in group C, or a placebo tablet in group P. Pain, sedation, patient satisfaction, total morphine consumption from a patient-controlled analgesia device, supplemental analgesic requirement, and the incidence of nausea and vomiting were recorded throughout 24 h after surgery. The mean pain score and total morphine consumption were found significantly lower in both M and C groups compared with group P (p < 0.001). There were no significant differences between group M and C with respect to pain scores (p = 0.117) and total morphine consumption (p = 0.090). Patients requested less supplemental analgesic and experienced less nausea and vomiting in groups M and C compared with group P. In conclusion, preoperative oral administration of 6 mg melatonin or 2 g vitamin C led to a reduction in pain scores, total morphine consumption, supplemental analgesic requirement, and the incidence of nausea and vomiting compared with placebo.

Efficacy of pre-emptive use of cyclooxyenase-2 inhibitors for total knee arthroplasty: a mini-review

Total knee arthroplasty (TKA) is regarded as the most effective surgery for patients with later-stage arthritis of the knee, but the postoperative pain management for functional improvement of the knew is still a challenging task. This review discusses the mechanism by which the selective cyclooxyenase-2 inhibitors, which reduce the peripheral and central sensitization, decrease pain after TKA. This review also covers the protocols, safety, efficacy, and progress of cyclooxyenase-2 inhibitors in pre-emptive analgesia.

The efficacy of pre-emptive analgesia on pain management in total knee arthroplasty: a mini-review

Total knee arthroplasty (TKA) is considered a cost-effective and efficacious treatment for patients with end-stage knee arthritis. Meanwhile, TKA has been regarded as one of the most painful orthopaedic surgeries. Pain control after TKA remains a challenging task. Many analgesic innovations are used to reduce the level of pain, but none has been proven to be the optimum choice till now. Multimodal analgesia incorporates the use of analgesic adjuncts with different mechanisms of action to enhance postoperative pain management. This approach is a preferable choice in relieving postoperative pain with minimum side effects. This paper aims to review pre-emptive analgesia for pain management in TKA. We reviewed the application of pre-emptive analgesia, its physiological mechanism, and the techniques.

Postoperative Analgesic Efficacy of Preemptive and Postoperative Lornoxicam or Tramadol in Lumbar Disc Surgery

Objective

To compare preemptive and postoperative analgesic efficacy of tramadol and lornoxicam administered before anaesthesia induction in lumbar discectomy.

Methods

This randomised, double-blind trial was conducted on 60 ASA I and II patients undergoing lumbar discectomy. Group L (n=30) received 3×8 mg day^-1 lornoxicam, and Group T (n=30) received 3×1.5 mg kg^-1 day^-1 tramadol. A verbal rating scale (VRS), the duration of effective analgesia, the number of additional analgesics used, adverse effects and patient satisfaction were evaluated at the postoperative 30^th minute and 1^st, 2^nd, 4^th, 6^th, 8^th, 12^th and 24^th hours.

Results

There were no significant differences between Groups L and T regarding demographic and clinical characteristics, the number of additional analgesics and the duration of effective analgesia, adverse effects and patient satisfaction. VRS scores of the patients in Group T were significantly higher than those in Group L at the postoperative 30^th minute (p=0.050) and the 1st hour (p=0.005).

Conclusion

Lornoxicam, which was used for preemptive and postoperative analgesia in lumbar disc surgery, had provided adequate and effective analgesia such as tramadol. Moreover, preemptive analgesia was quite effective in prevention and treatment of postoperative pain.

An evidence-based review of enhanced recovery after surgery in total knee replacement surgery

Rationale: Enhanced recovery after surgery is gaining popularity among orthopaedic surgeons across the globe and hence a strong evidence base had to be reviewed to make an evidence-based sustainable protocol.

Methods

The following databases, PubMed, OVID, Cochrane database and EMBASE were searched. The search was limited to 15 components of enhanced recovery after surgery programme which is divided into preoperative, intraoperative and postoperative phases. Inclusion criteria were restricted to articles published in English within the last 15 years and articles comprising of unicompartmental arthroplasty, revision knee arthroplasty, bilateral simultaneous knee arthroplasty and only hip arthroplasty excluded. The full texts were analysed and controversies and limitations of various studies were summarised.

Discussion

Each component of the programme was thoroughly reviewed and strength and weaknesses of the evidence base summarised. The strength of the evidence was assessed by critically appraising the study methodology and justifying the appropriateness of the inclusion in enhanced recovery after surgery protocol.

Conclusion

Enhanced recovery after surgery has already been used successfully in various surgical specialities. Enhanced recovery after surgery programmes in knee arthroplasty are yet to be established as a universal practice to be adopted globally. This evidence-based review provides an insight into the best evidence linked to each component and their rationale for inclusion in the proposed enhanced recovery after surgery protocol.

Pain descriptors of taxane acute pain syndrome (TAPS) in breast cancer patients-a prospective clinical study

BACKGROUND

Taxane acute pain syndrome (TAPS) is a clinically significant side-effect of taxane chemotherapy, often described as arthralgia and myalgia that occurs 2-3 days after infusion. The aim of this study was to assess pain descriptors used by patients during their experience of TAPS.

METHODS

A clinical prospective cohort study was conducted on breast cancer patients who had not received prior chemotherapy and were asked to complete diaries on three consecutive docetaxel treatment cycles on days 1-7, 14, and 21 (acute phase). Questionnaires to assess pain severity, descriptors of pain, and the interference in activities due to pain were adapted from the Brief Pain Inventory and the McGill Pain Questionnaire. Telephone questionnaire follow-up was done at 1, 3, 6, 9, and 12 months following docetaxel (delayed phase).

RESULTS

The most commonly used descriptor for acute and chronic pain was "aching" (90-96%). However, in the delayed phase of the study, "burning" (32-50%), "radiating" (39-48%), and "sharp" (40-69%) were used more often. In both acute and chronic pain phases, most patients experienced moderate/severe pain regardless of the location. Pain in cycle 1 was predictive of pain in subsequent taxane cycles (p < 0.0001). Pain in cycle 3 was predictive of chronic pain (p < 0.002).

CONCLUSIONS

The descriptors used by patients experiencing chemotherapy-induced pain (ChIP) may be reflective of the underlying mechanisms. It is suspected that TAPS initiates as an acute inflammatory pain, which over time develops into neuropathic pain, known as chemotherapy-induced peripheral neuropathy (CIPN). However, the subjective pain experience varies from patient to patient.

Are perioperative therapeutic doses of statins associated with postoperative pain and opioid consumption after hip surgery under spinal anaesthesia?

Background

The anti-inflammatory effects of statins have been suggested to relieve postoperative pain. This retrospective study tested the association between the perioperative routine use of statins in therapeutic doses, and opioid requirements and pain scores, after hip replacement surgery.

Methods

With IRB approval, data was obtained for adult patients who had elective hip replacement surgery under spinal anaesthesia at Cleveland Clinic between 2005 and 2015. Patients were compared using a joint hypothesis framework. We used the inverse probability of treatment weighting method to control for observed confounding factors (a total of 26).

Results

We included 611 statin users and 780 non-statin users. Pain score during the initial 72 h after surgery was 0.07 higher (95% CI: -0.02, 0.17) in statin users (noninferiority test in both directions P<0.001). The estimated ratio of geometric means in the cumulative i.v. morphine equivalent opioid consumption was 1.01 (95% CI: 0.93, 1.10) for statin vs non-statin users (noninferiority test P=0.001 in the hypothesized direction and<0.001 in the other direction) during the initial 72 h after surgery. The statin and non-statin patients were deemed equivalent on postoperative opioid consumption and pain score.

Conclusions

This is the first large retrospective clinical study that investigates the effects of statin use on postoperative pain and opioid consumption. We observed no difference between statin users and non-users during the initial 72 h after hip surgery. Our findings do not support the routine use of statins as part of an analgesic regimen.

How effective is periarticular drug infiltration in providing pain relief and early functional outcome following total hip arthroplasty?

The aim of the study was to compare the efficacy of periarticular injection of a cocktail of analgesic drugs (PIC) with epidural infiltration (EA), in providing postoperative pain relief and early functional improvement following Total Hip Arthroplasty (THA).

METHODS

50 patients undergoing unilateral THA were randomized to receive either EA or PIC for postoperative pain control. Postoperative pain relief, as determined by the visual analogue scale (VAS), functional recovery and side effects related to EA and PIC were assessed.

RESULTS

PIC resulted in significantly lower VAS scores [0.48(0.71) vs 3.04(2.07)] in the first 24 h after surgery [mean (SD)], when compared to EA. The pain relief continued to be significantly lower even on the 10th postoperative day. Functional recovery was significantly better in the PIC group, with patients being able to walk longer distances and climb steps more quickly following THA. EA, unlike PIC was associated with side effects like nausea, vomiting, motor weakness, back pain and urinary retention. The overall satisfaction rate with treatment was significantly better in PIC group (9.04/10) than those who received EA (7.76/10).

CONCLUSION

PIC provides significantly better pain control and functional recovery in the early postoperative period, with less side effects when compared with EA. PIC should be the choice for pain control following THA.

Intra-operative effect of interscalene brachial plexus block to arthroscopic rotator cuff repair surgery

INTRODUCTION

To determine whether the placement of an interscalene brachial plexus block (IBPB) with general anaesthesia before shoulder arthroscopy would be effective in establishing a clear visual field and in shortening the surgical procedure.

METHOD

This prospective randomized control trial study included 152 patients who had undergone arthroscopic rotator cuff repair. Group A received IBPB and group B did not receive IBPB. A visual clarity scale (VCS) was determined by arthroscopic visualization. The systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), duration of surgical procedure, VCS, and medication that was administered for haemodynamic stability were recorded.

RESULTS

The VCS was improved in group A at stages 2 and 3 of the surgical procedures (p < 0.05), but there were no significant difference at stages 1 (p = 0.288) and 4 (p = 0.062). SBP, DBP, and HR were higher in group B during surgery (p < 0.05). The administered analgesics were higher in group B (p = 0.003), but there were no differences in hypotensive agents (p = 0.287). No significant difference was observed for the duration of surgery (p = 0.704).

CONCLUSIONS

Pre-operative IBPB with general anaesthesia for arthroscopic rotator cuff repair was beneficial in maintaining haemodynamic stability and improving the VCS during surgery.

Propofol produces preventive analgesia via GluN2B-containing NMDA Receptor/ERK1/2 Signaling Pathway in a rat model of inflammatory pain

Abstract

Propofol, an intravenous anesthetic, has been shown to offer superior analgesic effect clinically. Whether propofol has preventive analgesic property remains unexplored. The present study investigated the antinociceptive effect of propofol and underlying molecular and cellular mechanisms via pre-emptive administration in a formalin-induced inflammatory pain model in rats. Male adult Sprague–Dawley rats were randomly allocated into four groups: naïve (Group Naïve), formalin injection only (Group Formalin), and formalin injection at 30 min (Group P-30 min) or 2 h (Group P-2 h) after intravenous infusion of propofol (0.6 mg kg−1 min−1) for 1 h. Nociceptive responses and protein expression of phosphorylated- or pan-GluN2B, ERK1/2, p38 mitogen-activated protein kinase, and c-Jun N-terminal kinase in the spinal dorsal horn were evaluated. Alteration of intracellular Ca2+ concentration induced by N-methyl-D-aspartate (NMDA) receptor agonists with or without pre-treatment of propofol was measured using fluorometry in SH-SY5Y cells while neuronal activation in the spinal dorsal horn by immunofluorescence. Pre-emptive propofol reduced pain with a delayed response to formalin and a reduction in hypersensitivity that lasted at least for 2 h. The formalin-induced activation of spinal GluN2B and ERK1/2 but not p38 or c-Jun N-terminal kinase was also diminished by propofol treatment. Preconditioning treatment with 3 µM and 10 µM of propofol inhibited Ca2+ influx mediated through NMDA receptors in SH-SY5Y cells. Propofol also reduced the neuronal expression of c-Fos and p-ERK induced by formalin. This study shows that pre-emptive administration of propofol produces preventive analgesic effects on inflammatory pain through regulating neuronal GluN2B-containing NMDA receptor and ERK1/2 pathway in the spinal dorsal horn.

A review of factors affecting analgesic selection in large animals undergoing translational research

The widespread physiological effects of pain in experimental animals are likely to reduce the validity of data except when pain itself is studied. Appropriately prescribed analgesics will limit pain and improve the welfare of animals undergoing noxious experimental procedures. However, their injudicious use may also introduce variability in data and limit study reproducibility. Optimizing both animal welfare and the value of scientific data from experimental studies requires the ability to identify, quantify and treat animal pain by applying a knowledge of analgesic pharmacology that is sympathetic to study objectives. This review first examines the reasons for promoting analgesic use in translational animal research and, in focussing on pigs and small ruminants, then identifies factors that should be considered when devising analgesic plans.

Dentists' attitudes towards acute pharmacological pain management in children and adolescents

AIM

This study aimed to investigate Swedish dentists' attitudes regarding pain management strategies for treating children and adolescents. It assessed recommendations for pre- and postoperative analgesics, and use of local anaesthesia, and whether application of these strategies differs between general dental practitioners (GDPs) and specialists in paediatric dentistry (SPDs).

DESIGN

We invited all GDPs (n = 807) in southern Sweden (Region Skåne), and all registered SPDs (n = 122) working in Sweden (929 actively practising dentists under age 65 years) to participate in a postal survey on pain management in paediatric dental care.

RESULTS

The SPDs reported using all types of pain-reducing strategies more frequently than GDPs except local anaesthesia when extracting a permanent premolar, which SPDs and GDPs used equally often. Preoperative analgesic use was greater among SPDs than GDPs. GDPs used local anaesthesia less frequently for filling therapy in primary teeth than in permanent teeth.

CONCLUSIONS

SPDs recommend preoperative analgesics more often than GDPs do. GDPs seem to underuse local anaesthetics when treating children and adolescents. SPDs also use pain management strategies more frequently than GDPs. Among GDPs, pain management is less frequent when treating primary teeth than permanent teeth.

Effect of intravenous paracetamol as pre-emptive compared to preventive analgesia in a pediatric dental setting: a prospective randomized study

BACKGROUND

Efficacy of pre-emptive analgesia compared to preventive regimen, managing postoperative pain is still controversial.

AIM

Evaluating the efficacy of intravenous (IV) paracetamol as pre-emptive analgesia compared to preventive post-treatment administration in pediatric dental setting.

DESIGN

In a prospective trial, 60 noncooperative children of ASA I, II aged 3-10 years who underwent dental rehabilitation under general anesthesia were randomly divided into two groups. Pre-emptive group (n = 30) received 15 mg/kg of IV paracetamol before the start of treatment. Preventive group (n = 30) received 15 mg/kg of paracetamol at the end of treatment. Analgesic efficacy was measured by visual analog scale of faces (VASOF), percentage of children received postoperative analgesia.

RESULTS

The VASOF results in the pre-emptive group were significantly lower compared to the preventive group at 4, 8, 12, and 24 h (0.0146, 0.0188, 0.0085, and 0.0001, respectively). Less children in the pre-emptive group received supplemental fentanyl postoperatively compared to the preventive group (27.6%, 58.6%, respectively, P = 0.0170). Time to first rescue dose of fentanyl postoperatively in the pre-emptive group was later than in the preventive group (P = 0.0432).

CONCLUSIONS

Administration of IV paracetamol pre-emptively provides lower pain scores, and a decreased percentage of children required pain relief and less amount of postoperative opioids, compared to preventive administration.

Chronic Opioid Use After Surgery: Implications for Perioperative Management in the Face of the Opioid Epidemic

Physicians, policymakers, and researchers are increasingly focused on finding ways to decrease opioid use and overdose in the United States both of which have sharply increased over the past decade. While many efforts are focused on the management of chronic pain, the use of opioids in surgical patients presents a particularly challenging problem requiring clinicians to balance 2 competing interests: managing acute pain in the immediate postoperative period and minimizing the risks of persistent opioid use after the surgery. Finding ways to minimize this risk is particularly salient in light of a growing literature suggesting that postsurgical patients are at increased risk for chronic opioid use. The perioperative care team, including surgeons and anesthesiologists, is poised to develop clinical- and systems-based interventions aimed at providing pain relief in the immediate postoperative period while also reducing the risks of opioid use longer term. In this paper, we discuss the consequences of chronic opioid use after surgery and present an analysis of the extent to which surgery has been associated with chronic opioid use. We follow with a discussion of the risk factors that are associated with chronic opioid use after surgery and proceed with an analysis of the extent to which opioid-sparing perioperative interventions (eg, nerve blockade) have been shown to reduce the risk of chronic opioid use after surgery. We then conclude with a discussion of future research directions.

The Importance of Optimizing Acute Pain in the Orthopedic Trauma Patient

Postoperative pain control is a highly studied topic because of its significant effect on costs, hospital course, and, most importantly, patient satisfaction. Opioid use has been the "status quo" of postoperative pain management but prolongs hospital stays and increases complications. Optimizing acute pain management in patients with orthopedic trauma is important and can translate into significant positive physiologic and financial outcomes. Although multiple viable examples of optimizing acute pain management in the literature demonstrate outcome improvements, implementation has not been widespread. Significant outcome success will depend more on systemwide implementation than a specific regimen for postoperative pain control.

Preoperative flurbiprofen axetil administration for acute postoperative pain: a meta-analysis of randomized controlled trials

OBJECTIVE

Non-steroidal anti-inflammatory drugs have been shown to effectively decrease postoperative pain and reduce opioid requirements. Flurbiprofen axetil is an injectable non-selective cyclooxygenase inhibitor that has a high affinity for inflammatory tissues to achieve targeted drug therapy and prolonged duration of action. This meta-analysis examined the use of preoperative flurbiprofen axetil and its impact on postoperative analgesia.

METHODS

An electronic literature search of the Library of PubMed, Cochrane CENTRAL, and EMBASE databases was conducted in Feb 2016. Searches were limited to randomized controlled trials. The primary outcome was pain scores. The secondary outcomes included cumulative postoperative opioid consumption and opioid-related adverse effects.

RESULTS

A total of nine RCT studies involving 457 patients were included in this study. Compared to patients without perioperative flurbiprofen axetil, patients treated with preoperative flurbiprofen axetil had lower pain scores at 2 h (SMD -1.00; 95% CI -1.57 to -0.43, P = 0.0006), 6 h (SMD -1.22; 95% CI -2.01 to -0.43; P = 0.002), 12 h (SMD -1.19; 95% CI -2.10 to -0.28; P = 0.01), and 24 h (SMD -0.79; 95% CI -1.31 to -0.27; P = 0.003) following surgery. Preoperative flurbiprofen axetil had no significant effect on postoperative opioid consumption (SMD -13.11; 95% CI -34.56 to 8.33; P = 0.23). There was no significant difference between the groups with regard to adverse effects. Compared to patients with postoperative flurbiprofen axetil, however, preoperative flurbiprofen axetil resulted in decreased pain score only at 2 h after operation.

CONCLUSIONS

Preoperative use of flurbiprofen axetil will result in significantly lower postoperative pain scores, but no difference in nausea, vomiting, and opioid consumption compared to those who did not receive flurbiprofen axetil. However, more homogeneous and well-designed clinical studies are necessary to determine whether preoperative flurbiprofen axetil administration has more efficacy than that given at the end of surgery.

Review of Top 10 Prescribed Drugs and Their Interaction with Dental Treatment

The proportion of people over age 60 is growing faster than any other group. Many patients take several medications to manage multiple chronic medical conditions. Poor oral health is common and dental visits by patients over the age of 65 are increasing. The dentist must recognize that these medications may interact with dental treatment. This article reviews the top 10 prescribed drugs as listed in the IMS Institute national prescription audit in January 2015 and reviews the interactions between these medications and dental treatment. The medications reviewed include levothyroxine, acetaminophen/hydrocodone, lisinopril, metoprolol, atorvastatin, amlodipine, metformin, omeprazole, simvastatin, and albuterol.