Safety and Efficacy of Hydromorphone as an Analgesic Alternative to Morphine in Acute Pain: A Randomized Clinical Trial

Gastrointestinal adverse effects associated with the use of intravenous oliceridine compared with intravenous hydromorphone or fentanyl in acute pain management utilizing adjusted indirect treatment comparison methods

Background: In the absence of head-to-head comparative data from randomized controlled trials, indirect treatment comparisons (ITCs) may be used to compare the relative effects of treatments versus a common comparator (either placebo or active treatment). For acute pain management, the effects of oliceridine have been compared in clinical trials to morphine but not to fentanyl or hydromorphone. Aim: To assess the comparative safety (specifically differences in the incidence of nausea, vomiting and opioid-induced respiratory depression [OIRD]) between oliceridine and relevant comparators (fentanyl and hydromorphone) through ITC analysis. Methods: A systematic literature review identified randomized clinical trials with oliceridine versus morphine and morphine versus fentanyl or hydromorphone. The ITC utilized the common active comparator, morphine, for the analysis. Results: A total of six randomized controlled trials (oliceridine - 2; hydromorphone - 3; fentanyl - 1) were identified for data to be used in the ITC analyses. The oliceridine data were reported in two studies (plastic surgery and orthopedic surgery) and were also reported in a pooled analysis. The ITC focused on nausea and vomiting due to limited data for OIRD. When oliceridine was compared with hydromorphone in the ITC analysis, oliceridine significantly reduced the incidence of nausea and/or vomiting requiring antiemetics compared with hydromorphone (both orthopedic surgery and pooled data), while results in plastic surgery were not statistically significant. When oliceridine was compared with hydromorphone utilizing data from Hong, the ITC only showed a trend toward reduced risk of nausea and vomiting with oliceridine that was not statistically significant across all three comparisons (orthopedic surgery, plastic surgery and combined). An ITC comparing oliceridine with a study of fentanyl utilizing the oliceridine orthopedic surgery data and combined orthopedic and plastic surgery data showed a trend toward reduced risk that was not statistically significant. Conclusion: In ITC analyses, oliceridine significantly reduced the incidence of nausea and/or vomiting or the need for antiemetics in orthopedic surgery compared with hydromorphone and a non-significant trend toward reduced risk versus fentanyl.

PBPK-PD model for predicting morphine pharmacokinetics, CNS effects and naloxone antagonism in humans

Morphine and morphine-6-glucuronide (M6G) produce central nervous system (CNS) effects by activating mu-opioid receptors, while naloxone is used mainly for the reversal of opioid overdose, specifically for the fatal complication of respiratory depression, but also for alleviating opioid-induced side effects. In this study we developed a physiologically-based pharmacokinetic-pharmacodynamic (PBPK-PD) model to simultaneously predict pharmacokinetics and CNS effects (miosis, respiratory depression and analgesia) of morphine as well as antagonistic effects of naloxone against morphine. The pharmacokinetic and pharmacodynamic parameters were obtained from in vitro data, in silico, or animals. Pharmacokinetic and pharmacodynamic simulations were conducted using 39 and 36 clinical reports, respectively. The pharmacokinetics of morphine and M6G following oral or intravenous administration were simulated, and the PBPK-PD model was validated using clinical observations. The Emax model correlated CNS effects with free concentrations of morphine and M6G in brain parenchyma. The predicted CNS effects were compared with observations. Most clinical observations fell within the 5th-95th percentiles of simulations based on 1000 virtual individuals. Most of the simulated area under the concentration-time curve or peak concentrations also fell within 0.5-2-fold of observations. The contribution of morphine to CNS effects following intravenous or oral administration was larger than that of M6G. Pharmacokinetics and antagonistic effects of naloxone on CNS effects were also successfully predicted using the developed PBPK-PD model. In conclusion, the pharmacokinetics and pharmacodynamics of morphine and M6G, antagonistic effects of naloxone against morphine-induced CNS effects may be successfully predicted using the developed PBPK-PD model based on the parameters derived from in vitro, in silico, or animal studies.

Morphine and Hydromorphone Effects, Side Effects, and Variability: A Crossover Study in Human Volunteers

BACKGROUND

Balancing between opioid analgesia and respiratory depression continues to challenge clinicians in perioperative, emergency department, and other acute care settings. Morphine and hydromorphone are postoperative analgesic standards. Nevertheless, their comparative effects and side effects, timing, and respective variabilities remain poorly understood. This study tested the hypothesis that IV morphine and hydromorphone differ in onset, magnitude, duration, and variability of analgesic and ventilatory effects.

METHODS

The authors conducted a randomized crossover study in healthy volunteers. Forty-two subjects received a 2-h IV infusion of hydromorphone (0.05 mg/kg) or morphine (0.2 mg/kg) 1 to 2 weeks apart. The authors measured arterial opioid concentrations, analgesia in response to heat pain (maximally tolerated temperature, and verbal analog pain scores at discrete preset temperatures to determine half-maximum temperature effect), dark-adapted pupil diameter and miosis, end-expired carbon dioxide, and respiratory rate for 12 h after dosing.

RESULTS

For morphine and hydromorphone, respectively, maximum miosis was less (3.9 [3.4 to 4.2] vs. 4.6 mm [4.0 to 5.0], P < 0.001; median and 25 to 75% quantiles) and occurred later (3.1 ± 0.9 vs. 2.3 ± 0.7 h after infusion start, P < 0.001; mean ± SD); maximum tolerated temperature was less (49 ± 2 vs. 50 ± 2°C, P < 0.001); verbal pain scores at end-infusion at the most informative stimulus (48.2°C) were 82 ± 4 and 59 ± 3 (P < 0.001); maximum end-expired CO2 was 47 (45 to 50) and 48 mmHg (46 to 51; P = 0.007) and occurred later (5.5 ± 2.8 vs. 3.0 ± 1.5 h after infusion start, P < 0.001); and respiratory nadir was 9 ± 1 and 11 ± 2 breaths/min (P < 0.001), and occurred at similar times. The area under the temperature tolerance-time curve was less for morphine (1.8 [0.0 to 4.4]) than hydromorphone (5.4°C-h [1.6 to 12.1] P < 0.001). Interindividual variability in clinical effects did not differ between opioids.

CONCLUSIONS

For morphine compared to hydromorphone, analgesia and analgesia relative to respiratory depression were less, onset of miosis and respiratory depression was later, and duration of respiratory depression was longer. For each opioid, timing of the various clinical effects was not coincident. Results may enable more rational opioid selection, and suggest hydromorphone may have a better clinical profile.

EDITOR’S PERSPECTIVE

Managing opioid waste, cost, and opportunity for drug diversion in the emergency department

INTRODUCTION

Management of pain is a component of 80% of all emergency department (ED) visits, and intravenous (IV) opioids are most commonly used to treat moderate to severe pain. Since the dose of stock vials is rarely purchased based on provider ordering patterns, there is often a discrepancy between ordered doses and the dose of the stock vial, leading to waste. Here, waste is defined as the difference between the dose of the stock vials used to fill an order and the ordered dose. Drug waste is problematic as it increases the chance of administering the incorrect dose, it is a source of lost revenue, and in the context of opioids, it increases the opportunity for drug diversion. In this study, we sought to utilize real-world data to describe the magnitude of morphine and hydromorphone waste in the studied EDs. We also applied scenario analyses based on provider ordering patterns to simulate the effects of cost versus opioid waste minimization when making purchasing decisions for the dose of stock vial of each opioid.

METHODS

This was an observational analysis of IV morphine and hydromorphone orders across three EDs within a health care system between December 1, 2014 and November 30, 2015. In the primary analysis we measured total waste and cost of all ordered hydromorphone and morphine, and we created logistic regression models for each opioid to estimate the odds that a given ordered dose would create waste. In the secondary scenario analysis we determined the total waste created and total cost to satisfy all written orders for both opioids with respect to prioritizing minimizing waste versus cost.

RESULTS

Among a total of 34,465 IV opioid orders, 7866 (35%) of morphine orders created 21,767 mg of waste, and 10,015 (85%) of hydromorphone orders created 11,689 mg of waste. Larger dose orders were associated with a smaller likelihood of waste in both morphine and hydromorphone due to the doses of stock vials available. In the waste optimization scenario, relative to the base scenario, total waste, which included waste from both morphine and hydromorphone, was reduced by 97% and cost was reduced by 11%. In the cost optimization scenario, cost was reduced by 28% but waste increased by 22%.

CONCLUSION

As hospitals continue to seek strategies to reduce costs and mitigate the harms of opioid diversion amidst the opioid epidemic, this study shows that optimizing the dose of the stock vial to minimize waste using provider ordering patterns, could mitigate risk while also reducing cost. Limitations included the use of data from EDs within a single health system, drug shortages that affected stock vial availability, and finally, the actual cost of stock vials, used for cost calculations, can differ based on a variety of factors.

Intravenous acetaminophen with morphine versus intravenous morphine alone for acute pain in the emergency room: protocol for a multicenter, randomized, placebo-controlled, double-blinded study (ADAMOPA)

BACKGROUND

In emergency medicine, pain is a frequent reason for consultation. However, there is a great variation in its management which is often insufficient. The use intravenous morphine alone or multimodal analgesia with paracetamol is recommended for severe pain. But robust data are lacking to justify the association of paracetamol with morphine versus morphine alone for pain management in the emergency room (ER). The aim of our study is therefore to assess if in patients with acute pain of moderate to severe intensity with a numerical verbal scale (NVS) ≥5 in the ER, the intravenous administration of morphine alone is not inferior to the administration of intravenous morphine combined with paracetamol at 30 min from the first administration of the study drug.

METHODS

ADAMOPA is a prospective, non-inferiority, multicenter, placebo-controlled, parallel-group, randomized (1:1), double-blind trial. Subjects will be enrolled in the ER if they experience moderate to severe, acute, non-traumatic, and traumatic pain, defined as an NVS ≥5. The primary endpoint will be the between-group difference in mean change in NVS pain scores among patients receiving the combination of intravenous morphine plus paracetamol or intravenous morphine given alone, measured from the time before administration of the study medication to 30 min later.

DISCUSSION

This trial will determine the clinical utility of the association of paracetamol with morphine for pain management in the emergency room. The ADAMOPA trial will be conducted in accordance with the International Council on Harmonization Good Clinical Practices.

TRIAL REGISTRATION

EudraCT number: 2019-002149-39.

CLINICALTRIALS

gov identifier: NCT04148495. Date of trial registration: November 1, 2019.

A Randomized, Placebo-Controlled Study of Intranasal Fentanyl as an Analgesic Adjunct For Incision and Drainage of Abscess

BACKGROUND

Incision and drainage (I&D) of abscesses is one of the most painful procedures performed in emergency departments (EDs).

OBJECTIVE

We tested the following hypothesis: The addition of intranasal fentanyl to the standard practice of local infiltration with lidocaine would provide better pain control than lidocaine alone for adult ED patients undergoing I&D.

METHODS

This was a randomized, double-blind study. Participants received 2 μg/kg of intranasal fentanyl or a comparable amount of intranasal water in addition to local lidocaine infiltration. The primary outcome, which we assessed immediately after the I&D was completed, was a summary 0-10 pain score for which we asked study subjects to provide a number depicting their entire experience with the procedure.

RESULTS

During a 19-month enrollment period, we screened 176 patients for eligibility and enrolled 49; 25 received placebo and 24 received fentanyl. Baseline characteristics were comparable. Mean (standard deviation) summary pain scores were as follows: fentanyl 6.2 (3.3) and placebo 7.0 (3.2). The 95% confidence interval for a rounded between-group difference of 0.9 was -1.1 to 2.6.

CONCLUSIONS

In this small study, the addition of intranasal fentanyl did not substantially impact the pain scores of ED patients undergoing I&D.

Return Encounters in Emergency Department Patients Treated with Phenobarbital Versus Benzodiazepines for Alcohol Withdrawal

INTRODUCTION

Phenobarbital has been successfully used in the emergency department (ED) to manage symptoms of alcohol withdrawal, but few studies have reported outcomes for ED patients who receive phenobarbital and are discharged. We compared return encounter rates in discharged ED patients with alcohol withdrawal who were treated with benzodiazepines and phenobarbital.

METHODS

This is a retrospective cohort study conducted at a single academic medical center utilizing chart review of discharged ED patients with alcohol withdrawal from July 1, 2016, to June 30, 2019. Patients were stratified according to ED management with benzodiazepines, phenobarbital, or a combination of both agents. The primary outcome was return ED encounter within three days of the index ED encounter. Multivariate logistic regression identified significant covariates of an ED return encounter.

RESULTS

Of 470 patients who were discharged with the diagnosis of alcohol withdrawal, 235 were treated with benzodiazepines, 133 with phenobarbital, and 102 with a combination of both. Baseline characteristics were similar among the groups. However, patients who received phenobarbital were provided significantly more lorazepam equivalents compared to patients who received benzodiazepines alone. Treatment with phenobarbital, alone or in combination with benzodiazepines, was associated with significantly lower odds of a return ED visit within three days compared with benzodiazepines alone [AOR 0.45 (95% CI 0.23, 0.88) p = 0.02 and AOR 0.33 (95% CI 0.15, 0.74) p = 0.007].

CONCLUSIONS

Patients who received phenobarbital for alcohol withdrawal were less likely to return to the ED within three days of the index encounter. Despite similar baseline characteristics, patients who received phenobarbital, with or without benzodiazepines, were provided greater lorazepam equivalents the ED.

Harmaline potentiates morphine-induced antinociception via affecting the ventral hippocampal GABA-A receptors in mice

Morphine is one of the most effective medications for treatment of pain, but its side effects limit its use. Therefore, identification of new strategies that can enhance morphine-induced antinociception and/or reduce its side effects will help to develop therapeutic approaches for pain relief. Considering antinociceptive efficacy of harmaline and also highlighted the important role of GABA-A receptors in the pain perception, this research aimed to determine whether the ventral hippocampal (vHip) GABA-A receptors are involved in the possible harmaline-induced enhancement of morphine antinociception. To achieve this, vHip regions of adult male mice were bilaterally cannulated and pain sensitivity was measured in a tail-flick apparatus. Intraperitoneally administration of morphine (0, 2, 4 and 6 mg/kg) or harmaline (0, 1.25, 5 and 10 mg/kg) increased the percentage of maximal possible effect (%MPE) and induced antinociception. Interestingly, co-administration of sub-effective doses of harmaline (5 mg/kg) and morphine (2 mg/kg) induced antinociception. Intra-vHip microinjection of muscimol (0, 200 and 300 ng/mice), a GABA-A receptor agonist, enhanced the anti-nociceptive effects of harmaline (2.5 mg/kg)+morphine (2 mg/kg) combination. Microinjection of the same doses of muscimol into the vHip by itself did not alter tail-flick latency. Intra-vHip microinjection of bicuculline (100 ng/mouse), a GABA-A receptor antagonist, did not cause a significant change in MPE%. Bicuculline (60 and 100 ng/mouse, intra-vHip) was administered with the harmaline (5 mg/kg)+morphine (2 mg/kg), and inhibited the potentiating effect of harmaline on morphine response. These findings favor the notion that GABAergic mechanisms in the vHip facilitate harmaline-induced potentiation of morphine response in the tail-flick test in part through GABA-A receptors. These findings shall provide insights and strategies into the development of pain suppressing drugs.

Relative addictive potential of opioid analgesic agents

Opioid overdoses and deaths continue to be a problem in the USA with a significant portion related to prescribed opioid analgesic agents. The role of pharmacogentic factors in opioid addiction is an active area of research. While all opioid analgesic agents have some addictive potential, it is clear that there are some with greater addictive potential. Oxycodone is the most widely abused opioid analgesic and it appears to predispose to chronic use with high likability by users. Fentanyl and hydromorphone are both very lipophilic allowing rapid penetration into the CNS, but are not rated as highly as other agents. Providers should consider the risk of addiction with the opioids they prescribe and give those with a lower addictive potential.

Association of Emergency Department Opioid Administration With Ongoing Opioid Use: A Retrospective Cohort Study of Patients With Back Pain

OBJECTIVES

Opioids are commonly administered in the emergency department (ED) and prescribed for the treatment of back pain. It is important to understand the unintended consequences of this approach to inform treatment decisions and the consideration of alternative treatments. Recent evidence has shown that ED opioid prescriptions are associated with future opioid use. The objective of this study was to measure the association of opioid administration in the ED to patients treated for back pain with future opioid use.

METHODS

This is a retrospective study of opioid-naïve adults discharged from the ED with a diagnosis of back pain. Patients were stratified by opioid therapy (none, ED administration only, prescription only, or ED administration + prescription). Relative risks of ongoing opioid use (filling >90-day supply in 180 days following ED visit as documented in the prescription drug monitoring program) were calculated for each opioid-therapy group and compared to the no-opioid group.

RESULTS

We identified 24,487 opioid naïve back pain patients. The median age was 38 years, 55% were female, and 56% were non-Hispanic white. A total of 41% received no opioid, 10% were only administered an opioid in the ED, 18% only received a prescription, and 31% received an opioid in the ED + prescription. The adjusted relative risks of ongoing use compared to the no opioid group were as follows: ED only 1.9, prescription only 2.1, and ED + prescription 2.3. The increased risk persisted for other definitions of ongoing use and after adjustment for baseline pain scores.

CONCLUSIONS

For opioid-naïve patients with back pain, both administration of an opioid in the ED and opioid prescriptions are associated with a doubling of the risk of ongoing opioid use compared to patients not treated with opioids. This supports the consideration of minimizing exposure to opioids while treating back pain in the ED.

Hydromorphone population pharmacokinetics in pediatric surgical patients

BACKGROUND

Hydromorphone is an opioid agonist used for pediatric analgesia. Due to lack of data, pediatric dosing (based on adult pharmacokinetic models) is not optimal.

AIM

This study characterizes hydromorphone population pharmacokinetics in pediatric surgical patients.

METHODS

In this prospective observational study, 34 children (4-18 years, bodyweight 23-89.6 kg) received multiple intravenous hydromorphone boluses followed by postoperative hydromorphone patient-controlled analgesia. Arterial blood samples were collected before and at 3, 10, 30, and 90 (and few samples at 1350) minutes after the first dose. Hydromorphone concentrations were measured by validated LC-MS/MS assay. Nonlinear mixed-effects modeling was used for pharmacokinetic model development. The final population pharmacokinetic model was evaluated by visual predictive check and bootstrap analysis. Monte Carlo simulations based on the final pharmacokinetic model determined optimal patient-controlled analgesia parameters to achieve a target of 20 ng/mL (as the median effective analgesic concentration), using minimum effective analgesic concentration of 4 ng/mL as a proxy for patient-controlled analgesia dose demand, and not exceeding the defined safe upper threshold of 40 ng/mL.

RESULTS

Hydromorphone pharmacokinetic profiles were adequately described by a two-compartmental model with first-order elimination. Bodyweight was found to be a significant covariate for hydromorphone clearance. Allometrically scaledpharmacokinetic parameter estimates (per 70 kg), systemic clearance (0.748 L/min), volume of distribution (33 L), peripheral clearance (1.57 L/min), and peripheral volume of distribution (146 L) were similar to reported adult parameter estimates. Sex, race, age, and type of surgery were not identified as significant covariates. To identify optimal patient-controlled analgesia dosing parameters, we simulated several initial loading doses, demand doses, and lockout intervals. Our simulations support an initial patient-controlled analgesia loading dose of 15 µg/kg followed by a demand dose of 6 µg/kg with lockout intervals of 20 minutes.

CONCLUSIONS

After intravenous hydromorphone, plasma pharmacokinetic profiles in children undergoing different surgeries were well described by a two-compartment population allometric pharmacokinetic model using bodyweight as the size descriptor. Model informed simulations identified patient-controlled analgesia parameters to inform initial settings, with adjustments as needed based on observed individual effects.

Pooled Dosing and Efficacy Analysis of the Sufentanil Sublingual Tablet 30 mcg Across Demographic Subgroups for the Management of Moderate-to-Severe Acute Pain

PURPOSE

To aid nurses in dosing sufentanil sublingual tablet (SST) 30 mcg administered via a single-dose applicator, dosing requirements and efficacy of SST 30 mcg were analyzed across age, sex, race, and body mass index subgroups.

DESIGN

Patient characteristics were pooled from three postoperative studies (two placebo-controlled and one open-label) and one open-label emergency department study. Drug dosing and efficacy data were pooled from the postoperative studies.

METHODS

Efficacy was assessed through summed pain intensity difference to baseline during 12 hours across subgroups.

FINDINGS

Mean (standard deviation) drug doses administered from 0 to 12 hours was 3.9 (2.0) for SST 30 mcg and was less frequent for older (≥65 years) versus younger patients. The summed pain intensity difference to baseline during 12 hours was superior with SST 30 mcg versus placebo across all subgroups.

CONCLUSIONS

SST 30 mcg is a sublingual opioid analgesic with efficacy across demographic subgroups.

A Randomized, Double-Blind, Placebo-Controlled Trial of Intravenous Acetaminophen on Hospital Length of Stay in Obese Individuals Undergoing Sleeve Gastrectomy

BACKGROUND

Retrospective studies indicate that acetaminophen iv administration reduces hospital length of stay (LoS) and opiate consumption in patients undergoing bariatric surgery.

OBJECTIVE

This study sought to determine whether using acetaminophen iv in morbidly obese subjects undergoing sleeve gastrectomy decreased LoS and total hospital charges as compared to patients receiving saline placebo.

SETTING

Single-center university hospital METHODS: Using a randomized, double-blind, placebo-controlled design, subjects were assigned to receive either acetaminophen iv (group A) or saline placebo iv (group P). Data were collected between Jan 1 and Dec 31, 2016. Group A received acetaminophen every 6 h for a total of four doses. The first dose was administered following the induction of general anesthesia; group P received saline iv on the same schedule. Anesthetic management and prophylactic antiemetic regimen were standardized in all subjects. Postoperative pain management consisted of hydromorphone via patient-controlled infusion pump. Primary outcomes include hospital LoS and associated hospital costs. Secondary outcomes include patient satisfaction and postoperative nausea and pain scores.

RESULTS

Subject demographics (n = 127) and intraoperative management were similar in the two groups. Across all subjects, median hospital LoS in group A (n = 63) was 1.87 vs. 1.97 days in group P (n = 64) (p = 0.03, Wilcoxon rank-sum test). Postoperatively, daily quality-of-recovery (QoR-15) scores, narcotic consumption, and the use of rescue antiemetics were not significantly different between groups. Median hospital costs were as follows: group A, $12,885 vs. group P, $12,977 (n = 64).

CONCLUSIONS

Acetaminophen iv may reduce hospital LoS in subjects undergoing sleeve gastrectomy.

Formulation of Bioerodible Ketamine Microparticles as an Analgesic Adjuvant Treatment Produced by Supercritical Fluid Polymer Encapsulation

Pain is inadequately relieved by escalating doses of a strong opioid analgesic such as morphine in up to 25% of patients with cancer-related severe pain complicated by a neuropathic (nerve damage) component. Hence, there is an unmet medical need for research on novel painkiller strategies. In the present work, we used supercritical fluid polymer encapsulation to develop sustained-release poly(lactic-co-glycolic acid) (PLGA) biodegradable microparticles containing the analgesic adjuvant drug ketamine, for injection by the intrathecal route. Using this approach with a range of PLGA co-polymers, drug loading was in the range 10⁻60%, with encapsulation efficiency (EE) of 60⁻100%. Particles were mainly in the size range 20⁻45 µm and were produced in the absence of organic solvents and surfactants/emulsifiers. Investigation of the ketamine release profiles from these PLGA-based microparticles in vitro showed that release took place over varying periods in the range 0.5⁻4.0 weeks. Of the polymers assessed, the ester end-capped PLGA5050DLG-1.5E gave the best-controlled release profile with drug loading at 10%.

Change in Pain Score after Administration of Analgesics for Lower Extremity Fracture Pain during Hospitalization

BACKGROUND

Effective acute pain management following injury is critical to improve short-and long-term patient outcomes. Analgesics can effectively reduce pain intensity, yet half of injury patients report moderate to severe pain during hospitalization.

PURPOSE

The primary aim of this study was to identify the analgesic, different analgesic combinations, or analgesic and adjuvant analgesic combination that generated the largest percent change from pre- to post-analgesic pain score.

DESIGN

This was a descriptive retrospective cohort study of 129 adults admitted with lower extremity fractures to a trauma center.

METHODS

Name, dose, and frequency of analgesics and adjuvant analgesics administered from admission to discharge were collected from medical records. Percent change was calculated from pain scores documented on the 0-10 numeric rating scale.

RESULTS

The analgesic with largest percent change from pre- to post-administration pain score was hydromorphone 2 mg IV (53%) for the emergency department and morphine 4 mg IV (54%) for the in-patient unit. All analgesics administered in the emergency department and ∼50% administered on the in-patient unit produced a minimal (15%) decrease in pain score.

CONCLUSIONS

This study revealed that few analgesics administered in the emergency department and the in-patient unit to patients with lower extremity fractures provide adequate pain relief. In the emergency department, all analgesics administered resulted in at least minimal improvement of pain. On the in-patient unit 13 analgesic doses resulted at least minimal improvement in pain while nine doses did not even reach 20% change in pain. Findings from this study can be used guide the treatment of fracture pain in the hospital.

Analgesics Administered for Pain During Hospitalization Following Lower Extremity Fracture: A Review of the Literature

Effective treatment of acute pain during hospitalization following lower extremity fracture is critical to improve short-term patient outcomes including wound healing, stress response, hospital length of stay, and cost as well as minimizing long-term negative patient outcomes such as delayed return to work, disability, and chronic pain. As many patients report moderate to severe pain during hospitalization, identifying the analgesics that most effectively reduces pain is a priority to improve patient outcomes. The purpose of this review was to examine published studies describing patient response to analgesics administered orally (PO) or intravenously (IV) in the immediate hospitalization following lower extremity fracture. PubMed was queried for articles published through May 2017 that included information on type of study, population, fracture site, pain measurement tool, analgesic, and result. Of 514 articles found, eight met the inclusion criteria. Analgesics administered PO or IV were fentanyl, hydromorphone, morphine, remifentanil, diclofenac, ibuprofen, ketorolac, and etoricoxib. Five of the studies focused on comparisons between one or more analgesics and three studies compared an IV analgesic to a regional anesthetic agent. Two studies compared different nonsteroidal anti-inflammatory drugs (NSAIDs). Bupivacaine, lignocaine, and levobupivacaine administered as regional nerve blocks were superior to controlling pain compared with IV fentanyl and IV hydromorphone. IV morphine provided faster and better pain relief compared with IV ibuprofen. Based on the limited data available, regional nerve blocks provided superior pain relief compared with opioids, and opioids provided superior pain relief compared with NSAIDs. Different NSAIDs provided similar pain relief.

Pain Management in the Emergency Department: a Review Article on Options and Methods

CONTEXT

The aim of this review is to recognizing different methods of analgesia for emergency medicine physicians (EMPs) allows them to have various pain relief methods to reduce pain and to be able to use it according to the patient's condition and to improve the quality of their services.

EVIDENCE ACQUISITION

In this review article, the search engines and scientific databases of Google Scholar, Science Direct, PubMed, Medline, Scopus, and Cochrane for emergency pain management methods were reviewed. Among the findings, high quality articles were eventually selected from 2000 to 2018, and after reviewing them, we have conducted a comprehensive comparison of the usual methods of pain control in the emergency department (ED).

RESULTS

For better understanding, the results are reported in to separate subheadings including "Parenteral agents" and "Regional blocks". Non-opioids analgesics such as nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen are commonly used in the treatment of acute pain. However, the relief of acute moderate to severe pain usually requires opioid agents. Considering the side effects of systemic drugs and the restrictions on the use of analgesics, especially opioids, regional blocks of pain as part of a multimodal analgesic strategy can be helpful.

CONCLUSION

This study was designed to investigate and identify the disadvantages and advantages of using each drug to be able to make the right choices in different clinical situations for patients while paying attention to the limitations of the use of these analgesic drugs.

Satisfactory Analgesia with Minimal Emesis in Day Surgeries (SAME DayS): a protocol for a randomised controlled trial of morphine versus hydromorphone

INTRODUCTION

There has been an exponential increase in the number of ambulatory surgeries (AS). Pain and postoperative nausea vomiting (PONV) affects the recovery, discharge and overall satisfaction of patients having AS. Opioids remain the primary modality for moderate to severe pain. Since there is no perfect opioid, physicians should ideally use the opioid that optimally balances benefits and risks. Present decisions on the choice between morphine (M) and hydromorphone (HM) are based on individual experience and observation. Our primary objective is to compare the proportion of patients having AS achieving satisfactory analgesia without significant PONV when using M compared with HM. Secondarily we will compare the proportion of patients with adverse events, analgesic used, patient satisfaction, time to discharge and postdischarge symptoms.

METHODS AND ANALYSIS

This is a two-arm, multicentre, parallel group, randomised controlled trial of 400 patients having AS. Eligible patients undergoing AS of the abdominal and pelvic regions with a potential to cause moderate to severe pain will be recruited in the preoperative clinic. Using a computer-generated randomization, with a 1:1 allocation ratio, patients will be randomised to M or HM. Patients, healthcare providers and research personnel will be blinded. Study interventions will be administered in the recovery using equianalgesic doses of M or HM in concealed syringes. Patients will be followed in hospital and up to 3 months. Intention-to-treat approach will be used for analysis.

ETHICS AND DISSEMINATION

This study has been approved by the Hamilton integrated research ethics board. We plan to publish our trial findings and present our findings at scientific meetings.

TRAIL REGISTRATION NUMBER

NCT02223377; Pre-results.

Use of Ultrasound-Guided Superficial Cervical Plexus Block for Pain Management in the Emergency Department

BACKGROUND

Although use of the superficial cervical plexus block (SCPB) by anesthesia for perioperative indications is well described, there is a paucity of research on use of SCPB in the emergency department (ED).

OBJECTIVE

This prospective observational study aims to prospectively characterize the feasibility, potential for efficacy, and safety of ultrasound-guided SCPB in a convenience sample of ED patients presenting with painful conditions of the "cape" distribution of the neck and shoulder.

METHODS

Data were gathered prospectively on a convenience sample of 27 patients presenting to a community ED with painful conditions involving the distribution of the SCPB: para-cervical muscle spasm/pain (n = 8), clavicle fractures (n = 7), acromioclavicular joint injuries (n = 3), radicular pain (n = 3), and rotator cuff disorders (n = 6). Pre- and post-block 11-point verbal numeric pain scores (VNPS) were recorded, as was the incidence of any immediate complications. A retrospective chart review looked for delayed complications in the 14-day post-block period.

RESULTS

The mean 11-point VNPS reduction was 5.4 points (62%). There were no early serious complications and one case each of self-limiting vocal hoarseness and asymptomatic hemi-diaphragmatic paresis. No delayed block-related complications were found.

CONCLUSIONS

While limited by the fact that this was a nonrandomized observational experience with no control group, our findings suggest that SCBP may be safe and have potential for efficacy, and warrants further evaluation in a randomized controlled trial.

Predictors of Response in Emergency Department Patients Receiving Intravenous Opioids for Severe Pain

The primary objective of this study was to identify significant environmental and patient characteristics of emergency department (ED) patients who responded to intravenous (IV) hydromorphone and IV morphine for severe pain. Secondary objectives were to investigate the individual effect of the significant environmental and patient characteristics of responders, and to assess the nature and strength of the correlation of initial dose and change in pain score from arrival to pre-administration. A retrospective chart review was performed in patients who received IV hydromorphone or morphine in the ED for severe pain. Key evaluated patient characteristics included patient demographics, recent opioid use, history of drug or alcohol abuse, and pain location, among others. Key evaluated environmental characteristics included initial opioid administered, time to first dose, initial pain score, and initial dose of opioid administered, among others. Environmental and patient characteristics associated with response to pain management were first identified using bivariate analyses and then entered into a multiple stepwise logistic regression mode. Patients were excluded if they were younger than 18 years, did not have a follow-up pain score within 2 hours of drug administration, or if they were discharged from the ED within 1 hour of administration. Patients meeting the inclusion criteria were grouped into two cohorts based on response and lack of response to treatment. A total of 200 patients were included. A decrease in pain score from arrival until pre-administration pain score and an inactive tobacco history had a positive association with response (odds ratio [OR] 1.488, 95% confidence interval [CI] 1.088-2.036, p=0.013, and OR 1.835, 95% CI 0.801-4.200, overall p=0.022, respectively). A higher initial dose and an active tobacco history had a negative association with response (OR 0.715, 95% CI 0.580-0.881, p=0.002, and OR 0.582, 95% CI 0.296-1.144, overall p=0.022, respectively). Two characteristics were associated with response to IV opioid pain management in the ED, inactive tobacco history and an increase in pain score from arrival until pre-administration, and two characteristics were associated with nonresponse to IV opioid pain management in the ED, active tobacco history and a higher initial dose. Previous literature supports both characteristics identified as risk factors but does not support either characteristic identified as protective factors, prompting the need for further research.

Administration of intravenous morphine for acute pain in the emergency department inflicts an economic burden in Europe

BACKGROUND

Acute pain is among the leading causes of referral to the emergency department (ED) in industrialized countries. Its management mainly depends on intensity. Moderate-to-severe pain is treated with intravenous (IV) administered opioids, of which morphine is the most commonly used in the ED. We have estimated the burden of IV administration of morphine in the five key European countries (EU5) using a micro-costing approach.

SCOPE

A structured literature review was conducted to identify clinical guidelines for acute pain management in EU5 and clinical studies conducted in the ED setting. The data identified in this literature review constituted the source for all model input parameters, which were clustered as analgesic (morphine), material used for IV morphine administration, nurse workforce time and management of morphine-related adverse events and IV-related complications.

FINDINGS

The cost per patient of IV morphine administration in the ED ranges between €18.31 in Spain and €28.38 in Germany. If costs associated with the management of morphine-related adverse events and IV-related complications are also considered, the total costs amount to €121.13-€132.43. The main driver of those total costs is the management of IV-related complications (phlebitis, extravasation and IV prescription errors; 73% of all costs) followed by workforce time (14%).

CONCLUSIONS

IV morphine provides effective pain relief in the ED, but the costs associated with the IV administration inflict an economic burden on the respective national health services in EU5. An equally rapid-onset and efficacious analgesic that does not require IV administration could reduce this burden.

Cost of Intravenous Analgesia for the Management of Acute Pain in the Emergency Department is Substantial in the United States

Background: Pain is a leading cause of admission to the emergency department (ED) and moderate-to-severe acute pain in medically supervised settings is often treated with intravenous (IV) opioids. With novel noninvasive analgesic products in development for this indication, it is important to assess the costs associated with IV administration of opioids. Materials and Methods: A retrospective observational study of data derived from the Premier database was conducted. All ED encounters of adult patients treated with IV opioids during a 2-year time period, who were charged for at least one IV opioid administration in the ED were included. Hospital reported costs were used to estimate the costs to administer IV opioids. Results: Over a 24 month-period, 7.3 million encounters, which included the administration of IV opioids took place in 614 US EDs. The mean cost per encounter of IV administration of an initial dose of the three most frequently prescribed opioids were: morphine $145, hydromorphone $146, and fentanyl $147. The main driver of the total costs is the cost of nursing time and equipment cost to set up and maintain an IV infusion ($140 ± 60). Adding a second dose of opioid, brings the average costs to $151-$154. If costs associated with the management of opioid-related adverse events and IV-related complications are also added, the total costs can amount to $269-$273. Of these 7.3 million encounters, 4.3 million (58%) did not lead to hospital admission of the patient and, therefore, the patient may have only required an IV catheter for opioid administration. Conclusions: IV opioid use in the ED is indicated for moderate-to-severe pain but is associated with significant costs. In subjects who are discharged from the ED and may not have required an IV for reasons other than opioid administration, rapid-onset analgesics for moderate-to-severe pain that do not require IV administration could lead to direct cost reductions and improved care.

Multimodal Analgesia, Current Concepts, and Acute Pain Considerations

PURPOSE OF REVIEW

Management of acute pain following surgery using a multimodal approach is recommended by the American Society of Anesthesiologists whenever possible. In addition to opioids, drugs with differing mechanisms of actions target pain pathways resulting in additive and/or synergistic effects. Some of these agents include alpha 2 agonists, NMDA receptor antagonists, gabapentinoids, dexamethasone, NSAIDs, acetaminophen, and duloxetine.

RECENT FINDINGS

Alpha 2 agonists have been shown to have opioid-sparing effects, but can cause hypotension and bradycardia and must be taken into consideration when administered. Acetaminophen is commonly used in a multimodal approach, with recent evidence lacking for the use of IV over oral formulations in patients able to take medications by mouth. Studies involving gabapentinoids have been mixed with some showing benefit; however, future large randomized controlled trials are needed. Ketamine is known to have powerful analgesic effects and, when combined with magnesium and other agents, may have a synergistic effect. Dexamethasone reduces postoperative nausea and vomiting and has been demonstrated to be an effective adjunct in multimodal analgesia. The serotonin-norepinephrine reuptake inhibitor, duloxetine, is a novel agent, but studies are limited and further evidence is needed. Overall, a multimodal analgesic approach should be used when treating postoperative pain, as it can potentially reduce side effects and provide the benefit of treating pain through different cellular pathways.

Predicting morphine related side effects in the ED: An international cohort study

STUDY OBJECTIVES

Morphine is the reference treatment for severe acute pain in an emergency department. The purpose of this study was to describe and analyse opioid-related ADRs (adverse drug reactions) in a large cohort of emergency department patients, and to identify predictive factors for those ADRs.

METHODS

In this prospective, observational, pharmaco-epidemiological international cohort study, all patients aged 18years or older who were treated with morphine were enrolled. The study was done in 23 emergency departments in the US and France. Baseline numerical rating scale score and initial and total doses of morphine titration were recorded. Logistic regression analysis was used to study the effects of demographic, clinical and medical history covariates on the occurrence of opioid-induced ADRs within 6h after treatment.

RESULTS

A total of 1128 patients were included over 10months. Median baseline initial pain scores were 8/10 (7-10) versus 3/10 (1-4) after morphine administration. Median titration duration was 10min (IQR, 1-30). The occurrence of opioid-induced ADRs was 25% and 2% were serious. Patients experienced mainly nausea and drowsiness. Medical history of travel sickness (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.01-2.86) and history of nausea or vomiting post morphine (OR, 3.86; 95% CI, 2.29-6.51) were independent predictors of morphine related ADRs.

CONCLUSION

Serious morphine related ADRs are rare and unpredictable. Prophylactic antiemetic therapy could be proposed to patients with history of travel sickness and history of nausea or vomiting in a postoperative setting or after morphine administration.

Morphine versus Hydromorphone: Does Choice of Opioid Influence Outcomes?

Morphine has traditionally been considered the first line agent for analgesia in hospitals; however, in the last few years there has been a shift towards the use of hydromorphone as a first line agent. We conducted a hospital population based observational study to evaluate the increasing use of hydromorphone over morphine in both medical and surgical populations. Additionally, we assessed the effect of this trend on three key outcomes, including adverse events, length of stay, and readmission rates. We evaluated data from the University Health Systems Consortium. Data from 38 hospitals from October 2010 to September 2013 was analyzed for patients treated with either hydromorphone or morphine. The use of morphine steadily decreased while use of hydromorphone increased in both medical and surgical groups. Rescue drugs were used more frequently in patients treated with hydromorphone in comparison to patients treated with morphine (p < 0.01). Patients receiving morphine tended to stay in the hospital for almost one day longer than patients receiving hydromorphone. However, 30-day all cause readmission rates were significantly higher in patients treated with hydromorphone (p < 0.01). Our study highlights that the choice of hydromorphone versus morphine may influence outcomes. There are implications related to resource utilization and these outcomes.

Novel polymeric bioerodable microparticles for prolonged-release intrathecal delivery of analgesic agents for relief of intractable cancer-related pain

Intractable cancer-related pain complicated by a neuropathic component due to nerve impingement is poorly alleviated even by escalating doses of a strong opioid analgesic. To address this unmet medical need, we developed sustained-release, bioerodable, hydromorphone (potent strong opioid)- and ketamine (analgesic adjuvant)-loaded microparticles for intrathecal (i.t.) coadministration. Drug-loaded poly(lactic-co-glycolic acid) (PLGA) microparticles were prepared using a water-in-oil-in-water method with evaporation. Encapsulation efficiency of hydromorphone and ketamine in PLGA (50:50) microparticles was 26% and 56%, respectively. Microparticles had the desired size range (20-60 μm) and in vitro release was prolonged at ≥28 days. Microparticles were stable for ≥6 months when stored refrigerated protected from light in a desiccator. Desirably, i.t. injected fluorescent dye-labeled PLGA microparticles in rats remained in the lumbar region for ≥7 days. In a rat model of neuropathic pain, i.t. coinjection of hydromorphone- and ketamine-loaded microparticles (each 1 mg) produced analgesia for 8 h only. Possible explanations include inadequate release of ketamine and/or hydromorphone into the spinal fluid, and/or insufficient ketamine loading to prevent development of analgesic tolerance to the released hydromorphone. As sub-analgesic doses of i.t. ketamine at 24-48 h intervals restored analgesia on each occasion, insufficient ketamine loading appears problematic. We will investigate these issues in future work.

Whole Genome Expression Profiling and Signal Pathway Screening of MSCs in Ankylosing Spondylitis

The pathogenesis of dysfunctional immunoregulation of mesenchymal stem cells (MSCs) in ankylosing spondylitis (AS) is thought to be a complex process that involves multiple genetic alterations. In this study, MSCs derived from both healthy donors and AS patients were cultured in normal media or media mimicking an inflammatory environment. Whole genome expression profiling analysis of 33,351 genes was performed and differentially expressed genes related to AS were analyzed by GO term analysis and KEGG pathway analysis. Our results showed that in normal media 676 genes were differentially expressed in AS, 354 upregulated and 322 downregulated, while in an inflammatory environment 1767 genes were differentially expressed in AS, 1230 upregulated and 537 downregulated. GO analysis showed that these genes were mainly related to cellular processes, physiological processes, biological regulation, regulation of biological processes, and binding. In addition, by KEGG pathway analysis, 14 key genes from the MAPK signaling and 8 key genes from the TLR signaling pathway were identified as differentially regulated. The results of qRT-PCR verified the expression variation of the 9 genes mentioned above. Our study found that in an inflammatory environment ankylosing spondylitis pathogenesis may be related to activation of the MAPK and TLR signaling pathways.

Randomized clinical trial of an intravenous hydromorphone titration protocol versus usual care for management of acute pain in older emergency department patients

BACKGROUND AND OBJECTIVES

Opioid titration is an effective strategy for treating pain; however, titration is generally impractical in the busy emergency department (ED) setting. Our objective was to test a rapid, two-step, hydromorphone titration protocol against usual care in older patients presenting to the ED with acute severe pain.

METHODS

This was a prospective, randomized clinical trial of patients 65 years of age and older presenting to an adult, urban, academic ED with acute severe pain. The study was registered at http://www.clinicaltrials.gov (NCT01429285). Patients randomized to the hydromorphone titration protocol initially received 0.5 mg intravenous hydromorphone. Patients randomized to usual care received any dose of any intravenous opioid. At 15 min, patients in both groups were asked, 'Do you want more pain medication?' Patients in the hydromorphone titration group who answered 'yes' received a second dose of 0.5 mg intravenous hydromorphone. Patients in the usual care group who answered 'yes' had their ED attending physician notified, who then could administer any (or no) additional medication. The primary efficacy outcome was satisfactory analgesia defined a priori as the patient declining additional analgesia at least once when asked at 15 or 60 min after administration of the initial opioid. Dose was calculated in morphine equivalent units (MEU: 1 mg hydromorphone = 7 mg morphine). The need for naloxone to reverse adverse opioid effects was the primary safety outcome.

RESULTS

83.0 % of 153 patients in the hydromorphone titration group achieved satisfactory analgesia compared with 82.5 % of 166 patients in the usual care group (p = 0.91). Patients in the hydromorphone titration group received lower mean initial doses of opioids at baseline than patients in the usual care group (3.5 MEU vs. 4.7 MEU, respectively; p ≤ 0.001) and lower total opioids through 60 min (5.3 MEU vs. 6.0 MEU; p = 0.03). No patient needed naloxone.

CONCLUSIONS

Low-dose titration of intravenous hydromorphone in increments of 0.5 mg provides comparable analgesia to usual care with less opioid over 60 min.

Hydromorphone: evolving to meet the challenges of today's health care environment

BACKGROUND

Hydromorphone, a potent analogue of morphine, has long had an important role in pain management and is included in several international guidelines for managing pain. Advances in hydromorphone formulations and the ways in which hydromorphone is being used clinically today warrant a review of the drug's pharmacotherapeutic utility.

OBJECTIVE

The history and recent advances in hydromorphone pharmacotherapy are reviewed. Areas covered include the pharmacologic and metabolic profile of hydromorphone, the role of hydromorphone in pain management, formulations and routes of administration, and issues related to relative opioid potencies, equianalgesic ratios, and opioid rotation. Because hydromorphone, like all opioids, carries a risk of misuse, abuse, and illicit diversion, the related issues of tamper-resistant formulations and "dose-dumping" of extended-release formulations are discussed.

CONCLUSIONS

Due to the epidemic of prescription opioid overdoses associated with prescription opioid abuse in the United States, development of tamper-resistant opioid formulations that avoid dose-dumping issues has become a significant goal of pharmaceutical manufacturers. The current formulation of hydromorphone extended-release potentially provides the benefits of long-acting hydromorphone (ie, continuous pain control, increased quality of life, freedom to perform daily activities) to appropriate patients, while reducing the risks of abuse and without compromising safety.

WITHDRAWN: Hydromorphone for acute and chronic pain

The original author team were unavailable to complete the update. At September 2013, a new author team is preparing a new protocol for publication in early 2014, with the revised title 'Hydromorphone for cancer pain'.

The editorial group responsible for this previously published document have withdrawn it from publication.

Versatility of different pharmaceutical formulations of hydromorphone in the management of severe cancer pain and pain in palliative care

SUMMARY The management of severe pain situations requires therapeutic expertise in dealing with changes in pain intensity, analgesic limitations and individual patient needs. Opioids are the treatment of choice in severe pain. The availability of a broad range of opioids and formulations refined the options for improved pain treatment with a specific substance. These may include oral formulations, injectables and other applications suitable for different patient needs. Moreover, variable drug concentrations are most useful in clinical practice. This article briefly reviews the versatility of different hydromorphone formulations in the management of severe pain in palliative care and cancer. Limiting strong opioid treatment with one opioid substance in different formulations (adjuvants if necessary), according to varying requirements of patients, would be eligible for achieving a well-tolerated and effective pain therapy. Its versatility renders hydromorphone suitable for consistent opioid administration with predictable substance release, and may thus contribute to reducing the need for opioid change.

Management of Pain in the Emergency Department

Since pain is a primary impetus for patient presentation to the Emergency Department (ED), its treatment should be a priority for acute care providers. Historically, the ED has been marked by shortcomings in both the evaluation and amelioration of pain. Over the past decade, improvements in the science of pain assessment and management have combined to facilitate care improvements in the ED. The purpose of this review is to address selected topics within the realm of ED pain management. Commencing with general principles and definitions, the review continues with an assessment of areas of controversy and advancing knowledge in acute pain care. Some barriers to optimal pain care are discussed, and potential mechanisms to overcome these barriers are offered. While the review is not intended as a resource for specific pain conditions or drug information, selected agents and approaches are mentioned with respect to evolving evidence and areas for future research.

Randomized clinical trial of efficacy and safety of a single 2-mg intravenous dose of hydromorphone versus usual care in the management of acute pain

OBJECTIVES

The objective was to test the efficacy and safety of 2 mg of intravenous (IV) hydromorphone (Dilaudid) against "usual care" in emergency department (ED) patients with acute severe pain.

METHODS

This was a randomized clinical trial. Patients allocated to 2 mg of IV hydromorphone received their medication in a single dose. Those randomized to usual care received any IV opioid, with type, dose, and frequency chosen by the ED attending. All patients received 2 L/min. nasal cannula oxygen. The primary outcome was the difference in the proportion of patients who achieved clinically satisfactory analgesia by 30 minutes. This was defined as the patient declining additional analgesia when asked the question, "Do you want more pain medicine?" A 10% absolute difference was chosen a priori as the minimum difference considered clinically significant.

RESULTS

Of 175 subjects randomized to each group, 164 in the 2 mg hydromorphone group and 161 in the usual care group had sufficient data for analysis. Additional pain medication was declined by 77.4% of patients in the 2 mg hydromorphone group at 30 minutes, compared to 65.8% in the usual care group. This difference of 11.6% was statistically and clinically significant (95% confidence interval [CI] = 1.8% to 21.1%). Safety profiles were similar and no patient required naloxone. There was more pruritus in the hydromorphone group (18.3% vs. 8.7%; difference = 9.6%, 95% CI = 2.6% to 16.6%).

CONCLUSIONS

Using a simple dichotomous patient-centered endpoint in which a difference of 10% in proportion obtaining adequate analgesia was considered clinically significant, 2 mg of hydromorphone in a single IV dose is clinically and statistically more efficacious when compared to usual care for acute pain management in the ED.

Effect of ketamine on intravenous patient-controlled analgesia using hydromorphone and ketorolac after the Nuss surgery in pediatric patients

Background

Nuss surgery is preferred in pectus excavatum repair because this procedure produces excellent cosmetic results and prevents postoperative distressed pulmonary function. However, the procedure causes severe pain due to thoracic expansion. This study was designed to investigate the analgesic effect of small doses of ketamine on an intravenous patient-controlled analgesia (IV-PCA) using hydromorphone and ketorolac for pain control after Nuss surgery.

Methods

Forty-four patients undergoing elective Nuss surgery were randomly assigned to receive hydromorphone 3 µg/kg/hr, ketorolac 0.05 mg/kg/hr and ondansetron 0.1 mg/kg/day (Group HO, n = 22) or hydromorphone 3 µg/kg/hr, ketorolac 0.05 mg/kg/hr, ondansetron 0.1 mg/kg/day and ketamine 0.15 mg/kg/hr (Group HK, n = 22) via an IV-PCA pump after surgery. A blind observer evaluated each patient using the Modified Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) for the assessment of pain control. The total administered PCA volume, side effects and parents satisfaction with pain control were assessed at postoperative 1, 4, 8, 12, 24, and 48 hours.

Results

There were no significant differences in Modified CHEOPS between the groups during postoperative 48 hours. The total PCA volume in group HK was significantly lower than that in group HO (P < 0.05). The side effects in both groups did not significantly differ except for pruritus. The levels of satisfaction from the parents were not significantly different between the groups.

Conclusions

A small dose of ketamine on IV-PCA reduced the total administered dose of IV-PCA with hydromorphone and ketorolac and reduced the incidence of pruritus after the Nuss procedure in pediatric patients.

Parenteral opioids in emergency medicine - A systematic review of efficacy and safety

Introduction and aim Pain is a frequent symptom in emergency patients and opioids are commonly used to treat it at emergency departments and at pre-hospital settings. The aim of this systematic review is to examine the efficacy and safety of parenteral opioids used for acute pain in emergency medicine. Method Qualitative review of randomized controlled trials (RCTs) on parenteral opioids for acute pain in adult emergency patients. Main outcome measures were: type and dose of the opioid, analgesic efficacy as compared to either placebo or another opioid and adverse effects. Results Twenty double-blind RCTs with results on 2322 patients were included. Seven studies were placebo controlled. Majority of studies were performed in the emergency department. Only five studies were in prehospital setting. Prehospital studies Four studies were on mainly trauma-related pain, one ischemic chest pain. One study compared two different doses of morphine in mainly trauma pain showing faster analgesia with the larger dose but no difference at 30 min postdrug. Three other studies on the same pain model showed equal analgesic effects with morphine and other opioids. Alfentanil was more effective than morphine in ischemic chest pain. Emergency department studies Pain models used were acute abdominal pain seven, renal colic four, mixed (mainly abdominal pain) three and trauma pain one study. Five studies compared morphine to placebo in acute abdominal pain and in all studies morphine was more effective than placebo. In four out of five studies on acute abdominal pain morphine did not change diagnostic accuracy, clinical or radiological findings. Most commonly used morphine dose in the emergency department was 0.1 mg/kg (five studies). Other opioids showed analgesic effect comparable to morphine. Adverse effects Recording and reporting of adverse effects was very variable. Vital signs were recorded in 15 of the 20 studies (including all prehospital studies). Incidence of adverse effects in the opioid groups was 5-38% of the patients in the prehospital setting and 4-46% of the patients in the emergency department. Nausea or vomiting was reported in 11-25% of the patients given opioids. Study drug was discontinued because of adverse effects five patients (one placebo, two sufentanil, two morphine). Eight studies commented on administration of naloxone for reversal of opioid effects. One patient out of 1266 was given naloxone for drowsiness. Ventilatory depression defined by variable criteria occurred in occurred in 7 out of 756 emergency department patients. Conclusion Evidence for selection of optimal opioid and dose is scarce. Opioids, especially morphine, are effective in relieving acute pain also in emergency medicine patients. Studies so far are small and reporting of adverse effects is very variable. Therefore the safety of different opioids and doses remains to be studied. Also the optimal titration regimens need to be evaluated in future studies. The prevention and treatment of opioid-induced nausea and vomiting is an important clinical consideration that requires further clinical and scientific attention in this patient group.

Comparative clinical effects of hydromorphone and morphine: a meta-analysis

We have conducted a meta-analysis of the clinical effects of morphine and hydromorphone to compare their benefit in analgesia. Embase and Medline were searched with an end-date of June 2009 for randomized, controlled trials or observational studies that addressed comparative analgesic and side-effects or particular side-effects. Two researchers independently identified included studies and extracted the data. Estimates of opioid effects were combined by using a random-effects model. Meta-analysis of eight studies suggested that hydromorphone (494 patients) provides slightly better (P=0.012) clinical analgesia than morphine (510 patients). The effect-size was small (Cohen's d=0.266) and disappeared when one study was removed, although the advantage of hydromorphone was more evident in studies of better quality (Jadad's rating). Side-effects were similar, for example, nausea (P=0.383, nine studies, 456 patients receiving hydromorphone and 460 morphine); vomiting (P=0.306, six studies, 246 patients receiving hydromorphone and 239 morphine); or itching (P=0.249, eight studies, 405 patients receiving hydromorphone, 410 morphine). This suggests some advantage of hydromorphone over morphine for analgesia. Additional potential clinical pharmacological advantages with regard to side-effects, such as safety in renal failure or during acute analgesia titration, are based on limited evidence and require substantiation by further studies.

Systematic review reveals heterogeneity in definition of a clinically relevant difference in pain

OBJECTIVE

To describe the pain decrease considered as clinically relevant when designing a trial and reporting its results.

METHODS

A systematic review of the literature in MEDLINE was conducted to select randomized controlled trials (RCTs) with pain as a primary outcome. Data extracted included the definition (terms and values) of a clinically relevant difference in pain, the type of pain studied (acute or chronic), the level of application (group or individual) of the clinically relevant difference, and the reference justifying the choice of value for clinically relevant difference.

STUDY DESIGN AND SETTING

Seventy-four trials were included, and only 16 articles justified the choice of a value for clinically relevant difference with a reference citation. The values chosen for the clinically relevant relative decrease in pain varied from 4 to 40 mm or from 15% to 55% at the group level and from 20 to 50 mm at the individual level. In seven articles, the authors confused the application of the reference value at the individual or group level.

CONCLUSION

Our review revealed a great heterogeneity in definition, format, and values of what is considered a clinically relevant difference in pain in RCTs of analgesics, and standardizations are advisable.