Intrathecal ketorolac enhances intrathecal morphine analgesia following total knee arthroplasty

Effects of local infiltration of analgesia and tranexamic acid in total knee replacements: safety and efficacy in reducing blood loss and comparability to intra-articular tranexamic acid

INTRODUCTION

The use of periarticular (PA) tranexamic acid (TXA) and its efficacy in comparison with intra-articular (IA) TXA have not been well explored in the literature. This retrospective cohort study aimed to compare the effects of IA and PA TXA with analgesic components in reducing blood loss and improving immediate postoperative pain relief and functional outcomes in patients after unilateral primary total knee arthroplasty (TKA).

METHODS

A total of 63 patients underwent TKA, and they were divided into the IA TXA delivery group ( n = 42) and PA TXA delivery group ( n = 21). All patients were administered 1 g of TXA. They also received pericapsular infiltration consisting of 0.5 mL of adrenaline, 0.4 mL of morphine, 1 g of vancomycin, 1 mL of ketorolac and 15 mL of ropivacaine. Outcomes for blood loss and surrogate markers for immediate functional recovery were measured.

RESULTS

Of the 63 patients, 54% were female and 46% male. The mean drop in postoperative haemoglobin levels in the PA and IA groups was 2.0 g/dL and 1.6 g/dL, respectively, and this was not statistically significant ( P = 0.10). The mean haematocrit drop in the PA and IA groups was 6.1% and 5.3%, respectively, and this was also not statistically significant ( P = 0.58). The postoperative day (POD) 1 and discharge day flexion angles, POD 1 and POD 2 visual analogue scale (VAS) scores, gait distance on discharge and length of hospitalisation stay were largely similar in the two groups.

CONCLUSION

Our study showed that both IA and PA TXA with analgesic components were equally efficient in reducing blood loss and improving immediate postoperative pain relief and functional outcomes.

Comparison of Analgesic Effects of Ketorolac Plus Apotel to Meperidine in Patients Undergoing Right Thoracotomy: A Double-Blind Randomized Clinical Trial

Background

Postoperative pain management using nonsteroidal anti-inflammatory drugs with no narcotic-attributed adverse effects, such as respiratory depression, nausea, and vomiting, is still the subject of extensive research. However, concerns about bleeding and nephrotoxicity have limited routine use.

Objectives

The present trial aimed to compare the effects of ketorolac/apotel and meperidine on postoperative pain relief in patients undergoing thoracotomy.

Methods

This randomized controlled trial enrolled 122 patients who were candidates for right thoracotomy. The patients were randomly divided into two groups that received ketorolac (30 mg)/apotel (1 g) or meperidine (0.5 - 1 mg/kg) at the beginning of recovery, respectively. This study assessed the Numeric Rating Scale pain score immediately and 30 and 60 minutes after the surgery in the recovery room, blood pressure, oxygen saturation (SpO2), sweating, and pulse rate.

Results

The average pain score at recovery time was significantly lower in the ketorolac/apotel group (2.06 ± 1.40) than in the meperidine group (2.76 ± 1.61) (P = 0.011). In contrast to the ketorolac/apotel group, an increasing trend was observed in pain scores in the meperidine group throughout the time sequence (P < 0.05). However, a slight non-significant increase was also observed in the ketorolac/apotel group. No statistical differences were observed in blood pressure (P = 0.826), SpO2 (P = 0.826), and pulse rate (P = 0.811) between the two study groups.

Conclusions

This study provides support that the combination of ketorolac/apotel offers a slightly superior analgesic effect for patients undergoing thoracotomy, compared to meperidine. Pain management is crucial during recovery, and the current study's findings suggest that administering ketorolac/apotel provides effective analgesia during recovery after thoracic surgery.

Does the combination of intrathecal fentanyl and morphine improve clinical outcomes in patients undergoing lumbar fusions?

Intrathecal morphine (ITM) has been widely effective in improving postoperative outcomes in patients undergoing a multitude of surgeries, including lumbar spine fusion. A major limitation of ITM administration is the increase in the incidence of respiratory depression in a dose-dependent manner. One way to bypass this is to use a more potent opioid with a shorter half-life, such as fentanyl. This is a retrospective analysis of patients who underwent one- or two-level transforaminal lumbar interbody fusions. The patients received one of two interventions: 0.2mg intrathecal duramorph/morphine (ITM group; n=70), 0.2mg duramorph + 50 mcg fentanyl (ITM + fentanyl group; n=68) and the control group (n=102). Primary outcomes included postoperative pain (Visual Analog Scale) and opioid intake (MED - morphine equivalent dosage, mg) for postoperative days (POD) 1- 4. Secondary outcomes included opioid-related side effects. One-way analyses of variance and follow-up post-hoc Tukey's honest significant difference statistical tests were used to measure treatment effects. Significantly lower POD1 pain scores for both the ITM and ITM + fentanyl groups vs. control were detected, with no difference between the ITM vs. ITM + fentanyl groups. Similar results were found for POD1 MED intake. A multivariate regression analysis controlling for confounding variables did not attenuate the differences seen in POD1 pain scores while revealing that only the ITM + fentanyl predicted a decrease in POD1 MED intake. No differences were seen for postoperative opioid-related side effects. Our study provides support for supplementing a low dose of both intrathecal morphine and fentanyl to improve postoperative outcomes.

The effect of intraoperative intrathecal opioid administration on the length of stay and postoperative pain control for patients undergoing lumbar interbody fusion

PURPOSE

In an effort to control postoperative pain more effectively in spinal fusion patients, intraoperative intrathecal morphine (ITM) administration is gaining popularity and acceptance with clinicians. This study seeks to determine the impact of intraoperative intrathecal opioid (ITO) administration following lumbar fusion surgery on postoperative pain and length of hospitalization as primary outcomes. Secondary outcomes will investigate postoperative opioid intake and side effects.

METHODS

The retrospective analysis of collected data was performed. The study compared patients undergoing one- or two-level transforaminal interbody fusions between 2019 and 2021 who intraoperatively received two different ITO doses (n = 89) vs. the reference group (n = 48) that did not receive ITO. The patients in the ITO group received either 0.2 mg (n = 44) of duramorph or 0.2 mg duramorph + 50 mcg fentanyl (n = 45). The effect of ITO was evaluated for the first four postoperative days (POD) on pain scores (visual analog scale), length of stay (LOS, hours) and opioid requirement (MED, morphine equivalent dose).

RESULTS

In the ITO group, a significant reduction of postoperative pain scores (t(99) = 4.3, p < 0.001) and opioid intake (t(70) = 2.49, p = 0.015) was noted on POD1. Cohen's d effect sizes were 0.76 and 0.50, meaning that postoperative pain and MED intake were reduced by about ¾ to ½ standard deviations (SD) in the ITO group. Further, multivariate regression models revealed that ITO administration predicted lower postoperative pain scores for the two PODs (β =  - 0.83, p < 0.001; β =  - 0.63, p = 0.022) and MED intake for the first two PODs (β =  - 20.8, p = 0.047; β =  - 16.4, p = 0.030). Mean LOS was 15.4 h less in the ITO group (mean ± SD, 63.4 ± 37.1 vs. 78.8 ± 39.6, p = 0.10).

CONCLUSIONS

In conclusion, our study provides results in a large sample of patients undergoing transforaminal lumbar fusions. The results demonstrated that ITO administration is effective in reducing POD1 pain scores and POD1-2 opioid requirement while not increasing the risk of any opioid-related side effects.

Pain management after total knee arthroplasty: PROcedure SPEcific Postoperative Pain ManagemenT recommendations

BACKGROUND

The PROSPECT (PROcedure SPEcific Postoperative Pain ManagemenT) Working Group is a global collaboration of surgeons and anaesthesiologists formulating procedure-specific recommendations for pain management after common operations. Total knee arthroplasty (TKA) is associated with significant postoperative pain that is difficult to treat. Nevertheless, pain control is essential for rehabilitation and to enhance recovery.

OBJECTIVE

To evaluate the available literature and develop recommendations for optimal pain management after unilateral primary TKA.

DESIGN

A narrative review based on published systematic reviews, using modified PROSPECT methodology.

DATA SOURCES

A literature search was performed in EMBASE, MEDLINE, PubMed and Cochrane Databases, between January 2014 and December 2020, for systematic reviews and meta-analyses evaluating analgesic interventions for pain management in patients undergoing TKA.

ELIGIBILITY CRITERIA

Each randomised controlled trial (RCT) included in the selected systematic reviews was critically evaluated and included only if met the PROSPECT requirements. Included studies were evaluated for clinically relevant differences in pain scores, use of nonopioid analgesics, such as paracetamol and nonsteroidal anti-inflammatory drugs and current clinical relevance.

RESULTS

A total of 151 systematic reviews were analysed, 106 RCTs met PROSPECT criteria. Paracetamol and nonsteroidal anti-inflammatory or cyclo-oxygenase-2-specific inhibitors are recommended. This should be combined with a single shot adductor canal block and peri-articular local infiltration analgesia together with a single intra-operative dose of intravenous dexamethasone. Intrathecal morphine (100 μg) may be considered in hospitalised patients only in rare situations when both adductor canal block and local infiltration analgesia are not possible. Opioids should be reserved as rescue analgesics in the postoperative period. Analgesic interventions that could not be recommended were also identified.

CONCLUSION

The present review identified an optimal analgesic regimen for unilateral primary TKA. Future studies to evaluate enhanced recovery programs and specific challenging patient groups are needed.

Periarticular Injection of Ketorolac Augmenting Intravenous Administration of Ketorolac for Postoperative Pain Control: A Randomized Controlled Trial in Simultaneous Bilateral Total Knee Arthroplasty

Adequate postoperative pain control with minimal side effects is necessary for patients undergoing total knee arthroplasty (TKA). Ketorolac is a frequently used nonsteroidal anti-inflammatory drug due to its excellent disposition in all administration routes; however, it possesses an "analgesic ceiling," which means that higher doses of the drug have no additional analgesic effect. Alternatively, increasing the local concentration of ketorolac via periarticular injection may provide additional pain relief to parenteral administration of ketorolac, but evidence demonstrating the benefits and safety of this approach is limited. Therefore, this study assesses whether local ketorolac injection could yield additional pain reduction to intravenous administration of ketorolac. A total of 54 patients who underwent simultaneous bilateral TKA were enrolled. Randomization was performed to determine whether 50 mg of bupivacaine plus 30 mg of ketorolac (ketorolac group), or only 50 mg bupivacaine (bupivacaine group) would be periarticularly injected into the first knee operated on (more painful), and then the contralateral knee would receive another mixture. Ketorolac (30 mg) was intravenously given every 8 hours for the first 48 hours. Visual analog scales (VASs) were used to assess pain, knee recovery function, and patients' preferred knee. Postoperative VAS pain scores in the ketorolac group were lower than those in the bupivacaine group 6 to 96 hours postoperatively and reached statistical significance 12 (4.25 ± 2.38 vs. 5.06 ± 2.48, respectively; p = 0.04) and 24 hours (4.22 ± 1.94 vs. 5.30 ± 2.12, respectively; p < 0.01) postoperatively. The ketorolac group had higher degrees of knee flexion and straight leg raise. No patient experienced adverse effects of ketorolac. On the day of discharge, 61.11% of the patients favored the knee that received local ketorolac injection (p < 0.01). Adjunct local ketorolac injection to systemic administration is well tolerated and may improve its analgesic effect as determined by the patients' perception.

The Options for Neuraxial Drug Administration

Neuraxial drug administration, i.e., the injection of drugs into the epidural or intrathecal space to produce anesthesia or analgesia, is a technique developed more than 120 years ago. Today, it still is widely used in daily practice in anesthesiology and in acute and chronic pain therapy. A multitude of different drugs have been introduced for neuraxial injection, only a part of which have obtained official approval for that indication. A broad understanding of the pharmacology of those agents is essential to the clinician to utilize them in a safe and efficient manner. In the present narrative review, we summarize current knowledge on neuraxial anatomy relevant to clinical practice, including pediatric anatomy. Then, we delineate the general pharmacology of neuraxial drug administration, with particular attention to specific aspects of epidural and intrathecal pharmacokinetics and pharmacodynamics. Furthermore, we describe the most common clinical indications for neuraxial drug administration, including the perioperative setting, obstetrics, and chronic pain. Then, we discuss possible neurotoxic effects of neuraxial drugs, and moreover, we detail the specific properties of the most commonly used neuraxial drugs that are relevant to clinicians who employ epidural or intrathecal drug administration, in order to ensure adequate treatment and patient safety in these techniques. Finally, we give a brief overview on new developments in neuraxial drug therapy.

Efficacy and safety of intrathecal morphine for analgesia after lower joint arthroplasty: a systematic review and meta-analysis with meta-regression and trial sequential analysis

Widespread adoption of intrathecal morphine into clinical practice is hampered by concerns about its potential side‐effects. We undertook a systematic review, meta‐analysis and trial sequential analysis with the primary objective of determining the efficacy and safety of intrathecal morphine. Our secondary objective was to determine the dose associated with greatest efficacy and safety. We also assessed the impact of intrathecal morphine on respiratory depression. We systematically searched the literature for trials comparing intrathecal morphine with a control group in patients undergoing hip or knee arthroplasty under spinal anaesthesia. Our primary efficacy outcome was rest pain score (0–10) at 8–12 hours; our primary safety outcome was the rate of postoperative nausea and vomiting within 24 hours. Twenty‐nine trials including 1814 patients were identified. Rest pain score at 8–12 hours was significantly reduced in the intrathecal morphine group, with a mean difference (95%CI) of −1.7 (−2.0 to −1.3), p < 0.0001 (19 trials; 1420 patients; high‐quality evidence), without sub‐group differences between doses (p = 0.35). Intrathecal morphine increased postoperative nausea and vomiting, with a risk ratio (95%CI) of 1.4 (1.3–1.6), p < 0.0001 (24 trials; 1603 patients; high‐quality evidence). However, a sub‐group analysis by dose revealed that rates of postoperative nausea and vomiting within 24 hours were similar between groups at a dose of 100 µg, while the risk significantly increased with larger doses (p value for sub‐group difference = 0.02). Patients receiving intrathecal morphine were no more likely to have respiratory depression, the risk ratio (95%CI) being 0.9 (0.5–1.7), p = 0.78 (16 trials; 1173 patients; high‐quality evidence). In conclusion, there is good evidence that intrathecal morphine provides effective analgesia after lower limb arthroplasty, without an increased risk of respiratory depression, but at the expense of an increased rate of postoperative nausea and vomiting. A dose of 100 µg is a ‘ceiling’ dose for analgesia and a threshold dose for increased rate of postoperative nausea and vomiting.

The Role of Intrathecal Morphine for Postoperative Analgesia in Primary Total Joint Arthroplasty under Spinal Anesthesia: A Systematic Review and Meta-Analysis

OBJECTIVE

To assess the efficacy and safety of intrathecal morphine (ITM) for postoperative analgesia in primary total joint arthroplasty (TJA) under spinal anesthesia and to explore the dose-response relationship for analgesic efficacy or risk of side effects.

METHODS

We searched MEDLINE, EMBASE, Web of Science, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov for any studies meeting the inclusion criteria. All the data were summarized using the random effects model. Subgroup analyses were performed based on the surgical procedure and dose of ITM. Meta-regression was used to explore the dose-response relationship.

RESULTS

Eighteen randomized controlled trials were included. Compared with the placebo or blank control, ITM reduced the postoperative 24-h morphine consumption by 10.07 mg and prolonged the duration of analgesia. However, ITM significantly increased the risk of pruritus by 2.79 fold, with a tendency to increase the risk of postoperative nausea and/or vomiting (P = 0.08). No difference was observed regarding the length of stay (LOS) and incidence of respiratory depression or urinary retention. Furthermore, meta-regression showed a linear dose-response relationship for the postoperative 24-h morphine consumption but no linear dose-response relationship for the risk of side effects.

CONCLUSIONS

Adding morphine to intrathecal anesthetics provides a prolonged and robust analgesic effect without significantly increasing the risk of side effects other than pruritus. Although we found a linear dose-response relationship for the postoperative 24-h morphine consumption, the optimal dose of ITM remains to be further explored in high-quality RCTs with a large sample size.

Intravenous versus oral acetaminophen as an adjunct on pain and recovery after total knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Total knee arthroplasty (TKA) is gradually emerging as the treatment of choice for end-stage osteoarthritis. In the past, intravenous (IV) versus oral acetaminophen (APAP) treatment is still a controversial subject in TKA. Therefore, we write this systematic review and meta-analysis to evaluate the efficacy of IV versus oral APAP on pain and recovery after TKA.

METHODS

Embase, Pubmed, and Cochrane Library were comprehensively searched. Randomized controlled trials, cohort studies were included in our meta-analysis. Five studies that compared IV APAP groups with oral APAP groups were included in our meta-analysis. The research was reported according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines to ensure the reliability and verity of results.

RESULTS

Pooled results indicated that no significant difference between the IV APAP groups and oral APAP groups in term of VAS score at 24 hours (P = .67), 48 hours (P = 0.08), and total morphine consumption at 24 hours (P = .07), but there was a significant difference in terms of length of hospital stay (LOS) (P = .0004).

CONCLUSION

IV APAP was not found to be superior to oral APAP in patients undergoing TKA in terms of VAS scores at 24 hours, 48 hours, and total morphine consumption at 24 hours. However, it can significantly reduce the LOS. We still need a large of high-quality research to verify the relationship between the oral and the IV APAP to give the conclusion.

Analgesic effect of perioperative ketamine for total hip arthroplasties and total knee arthroplasties: A PRISMA-compliant meta-analysis

BACKGROUND

Total hip arthroplasties (THA) and total knee arthroplasties (TKA) are always associated with a frequent incidence of postoperative pain. Effective pain management after surgery is quite essential for surgeons and patients. The purpose of the present meta-analysis is to evaluate the analgesic effect of perioperative ketamine after THA and TKA.

METHODS

Seven online databases, Embase, Cochrane Library, Pubmed, Web of Science, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Database (CBM), and Wanfang Data were searched for the related randomized controlled trials (RCT) by August 15, 2019. The qualities of the included studies were assessed based on the Cochrane Handbook for Systematic Reviews of Interventions 5.0. The visual analog scale (VAS), morphine equivalent consumption, and the side effects were used to evaluate the postoperative analgesic effect of ketamine by meta-analysis, which was performed by Review Manager version 5.3 software.

RESULTS

The VAS scores at 6 hours, 12 hours, 24 hours, and 48 hours after surgery were statistically lower in the ketamine group. The morphine equivalent consumptions in 24 hours and 48 hours after surgery were also significantly lower in the ketamine group. For the side effects, no statistical differences in odds ratio (OR) of sedation, dizziness, hallucination, sweating, pruritus, urinary retention, constipation, version trouble, nightmares, and delirium were observed between the ketamine group and the control group. But postoperative nausea and vomiting (PONV) showed lower OR in the ketamine group.

CONCLUSION

The present meta-analysis demonstrated perioperative ketamine could be used as a safe and effective analgesic agent for THA and TKA.

Intravenous acetaminophen as an adjunct to multimodal analgesia after total knee and hip arthroplasty: A systematic review and meta-analysis

BACKGROUND

This meta-analysis aimed to perform a meta-analysis to investigate the impact of additional intravenous acetaminophen for pain management after total joint arthroplasty (TJA).

METHODS

We conducted electronic searches of Medline (1966-2017.07), PubMed (1966-2017.07), Embase (1980-2017.07), ScienceDirect (1985-2017.07) and the Cochrane Library. Randomized controlled trials (RCTs) and non-RCTs were included. The quality assessments were performed according to the Cochrane systematic review method. The primary outcomes were postoperative pain scores and opioid consumption. Meta-analysis was performed using Stata 11.0 software.

RESULTS

A total of four studies were retrieved involving 865 participants. The present meta-analysis indicated that there were significant differences between groups in terms of pain scores at POD 1 (WMD = -0.954, 95% CI: -1.204 to -0.703, P = 0.000), POD 2 (WMD = -1.072, 95% CI: -2.072 to -0.073, P = 0.000), and POD 3 (WMD = -0.883, 95% CI: -1.142 to -0.624, P = 0.000). Significant differences were found regarding opioid consumption at POD 1 (WMD = -3.144, 95% CI: -4.142 to -2.146, P = 0.000), POD 2 (WMD = -5.665, 95% CI: -7.383 to -3.947, P = 0.000), and POD 3 (WMD = -3.563, 95% CI: -6.136 to -0.991, P = 0.007).

CONCLUSION

Additional intravenous acetaminophen to multimodal analgesia could significantly reduce pain and opioid consumption after total joint arthroplasty with fewer adverse effects. Higher quality RCTs are required for further research.

Multimodal infiltration of local anaesthetic in total knee arthroplasty; is posterior capsular infiltration worth the risk?

Aims

Multimodal infiltration of local anaesthetic provides effective control of pain in patients undergoing total knee arthroplasty (TKA). There is little information about the added benefits of posterior capsular infiltration (PCI) using different combinations of local anaesthetic agents. Our aim was to investigate the effectiveness of the control of pain using multimodal infiltration with and without infiltration of the posterior capsule of the knee.

Patients and Methods

In a double-blind, randomised controlled trial of patients scheduled for unilateral primary TKA, 86 were assigned to be treated with multimodal infiltration with (Group I) or without (Group II) PCI. Routine associated analgesia included the use of bupivacaine, morphine, ketorolac and epinephrine. All patients had spinal anaesthesia and patient-controlled analgesia (PCA) post-operatively. A visual analogue scale (VAS) for pain and the use of morphine were recorded 24 hours post-operatively. Side effects of the infiltration, blood loss, and length of stay in hospital were recorded.

Results

There were no statistically significant differences between the groups in relation to: VAS pain scores in the first 24 hours post-operatively (p = 0.693), the use of morphine in the PCA (p = 0.647), blood loss (p = 0.625), and length of stay (p = 0.17). There were no neurovascular complications in either group.

Conclusion

The multimodal infiltration of local anaesthetic with infiltration of the posterior capsule did not provide significant added analgesic benefits or reduce the use of morphine after TKA. Multimodal infiltration is a satisfactory technique for the management of pain in these patients without the attendant risks of PCI. Cite this article: Bone Joint J 2017; 99-B:483–8.

Postoperative pain treatment after total knee arthroplasty: A systematic review

INTRODUCTION

The aim of this systematic review was to document efficacy, safety and quality of evidence of analgesic interventions after total knee arthroplasty (TKA).

METHODS

This PRISMA-compliant and PROSPERO-registered review includes all-language randomized controlled trials of medication-based analgesic interventions after TKA. Bias was evaluated according to Cochrane methodology. Outcomes were opioid consumption (primary), pain scores at rest and during mobilization, adverse events, and length of stay. Interventions investigated in three or more trials were meta-analysed. Outcomes were evaluated using forest plots, Grading of Recommendations Assessment, Development and Evaluation (GRADE), L'Abbe Plots and trial sequential analysis.

RESULTS

The included 113 trials, investigating 37 different analgesic interventions, were characterized by unclear/high risk of bias, low assay sensitivity and considerable differences in pain assessment tools, basic analgesic regimens, and reporting of adverse events. In meta-analyses single and continuous femoral nerve block (FNB), intrathecal morphine, local infiltration analgesia, intraarticular injection of local anaesthetics, non-steroidal anti-inflammatory drugs, and gabapentinoids demonstrated significant analgesic effects. The 24-hour morphine-sparing effects ranged from 4.2 mg (CI: 1.3, 7.2; intraarticular local anaesthetics), to 16.6 mg (CI: 11.2, 22; single FNB). Pain relieving effects at rest at 6 hours ranged from 4 mm (CI: -10, 2; gabapentinoids), to 19 mm (CI: 8, 31; single FNB), and at 24 hours from 3 mm (CI: -2, 8; gabapentinoids), to 16 mm (CI: 8, 23; continuous FNB). GRADE-rated quality of evidence was generally low.

CONCLUSION

A low quality of evidence, small sample sizes and heterogeneity of trial designs prohibit designation of an optimal procedure-specific analgesic regimen after TKA.

Current and Future Issues in the Development of Spinal Agents for the Management of Pain

Targeting analgesic drugs for spinal delivery reflects the fact that while the conscious experience of pain is mediated supraspinally, input initiated by high intensity stimuli, tissue injury and/or nerve injury is encoded at the level of the spinal dorsal horn and this output informs the brain as to the peripheral environment. This encoding process is subject to strong upregulation resulting in hyperesthetic states and downregulation reducing the ongoing processing of nociceptive stimuli reversing the hyperesthesia and pain processing. The present review addresses the biology of spinal nociceptive processing as relevant to the effects of intrathecally-delivered drugs in altering pain processing following acute stimulation, tissue inflammation/injury and nerve injury. The review covers i) the major classes of spinal agents currently employed as intrathecal analgesics (opioid agonists, alpha 2 agonists; sodium channel blockers; calcium channel blockers; NMDA blockers; GABA A/B agonists; COX inhibitors; ii) ongoing developments in the pharmacology of spinal therapeutics focusing on less studied agents/targets (cholinesterase inhibition; Adenosine agonists; iii) novel intrathecal targeting methodologies including gene-based approaches (viral vectors, plasmids, interfering RNAs); antisense, and toxins (botulinum toxins; resniferatoxin, substance P Saporin); and iv) issues relevant to intrathecal drug delivery (neuraxial drug distribution), infusate delivery profile, drug dosing, formulation and principals involved in the preclinical evaluation of intrathecal drug safety.

Endogenous opiates and behavior: 2014

This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants). This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants).

Intrathecal morphine for postoperative analgesia: Current trends

The practice of anesthesiology has always been governed by evidence-based medicine. The quick turnover rate of patients in the operating room and patient safety and satisfaction, have also further changed the way we practice anesthesia. The use of intrathecal (IT) opiates as an effective form of postoperative pain relief has been established for many years. Morphine was the first opioid used by IT route. In clinical practice, morphine is regarded as the gold standard, or benchmark, of analgesics used to relieve intense pain. Perhaps for this reason, IT morphine has been used for over 100 years for pain relief. IT morphine is one of the easiest, cost-effective and reliable techniques for postoperative analgesia and technical failures are rare. And yet there is no consensus amongst anesthesiologists regarding the dose of IT morphine. Like all other methods of pain relief, IT morphine also has some side effects and some of them are serious though not very common. This review article looks into some of the key aspects of the use of IT morphine for post-operative analgesia and various doses for different procedures are discussed. This article also describes the side effects of IT morphine and how to treat and prevent them.