Sufentanil is not superior to morphine for the treatment of acute traumatic pain in an emergency setting: a randomized, double-blind, out-of-hospital trial

Alfentanil for Pain Relief in a Swedish Emergency Medical Service - An Eleven-Year Follow-up on Safety and Effect

OBJECTIVES

Pain is a common symptom in prehospital emergency care and pain treatment in this context can be challenging. While previous research has assessed the use of morphine and other synthetic opioids for pain management in this setting, the evaluation of alfentanil is limited. The objective of this study was to evaluate the safety and effect of intravenous alfentanil when administered by ambulance nurses in prehospital emergency care.

METHODS

This retrospective observational study consecutively included patients suffering from pain, treated with alfentanil in a Swedish EMS service from September 2011 to 31 September 2022. Data regarding occurrence of adverse events (AE), serious adverse events (SAE) - were used for safety evaluation and pain scores with a visual analogue scale (VAS) before and after treatment were used for evaluation of pain treatment. These data were extracted from the electronic patients' medical records database for analysis. Univariate logistic regression analysis was used to identify significant predictors of AE following injection of alfentanil by nurses in prehospital emergency care.

RESULTS

During the evaluation period 17,796 patients received pain relief with alfentanil. Adverse events affected 2.5% of the patients, while serious adverse events were identified in 25 cases (0.01%). Out of the 5970 patients with a complete VAS score for pain, the median VAS score was 8 (IQR 3) before treatment and 4 (IQR 3) after treatment. The mean reduction in pain measured by VAS was -4.1 ± 2.6 from the time before, to the evaluation after alfentanil administration. The administration frequency increased during the first year up to a steady level during the later part of the evaluation period.

CONCLUSIONS

This study proposes that alfentanil represents a safe and efficacious alternative for addressing urgent pain relief within the prehospital emergency context. Alfentanil demonstrates efficacy in alleviating pain across various conditions, with a relatively low risk of adverse events or serious adverse events when administered cautiously.

Severe pain management in the emergency department: patient pathway as a new factor associated with IV morphine prescription

Background

Across the world, 25-29% of the population suffer from pain. Pain is the most frequent reason for an emergency department (ED) visit. This symptom is involved in approximately 70% of all ED visits. The effective management of acute pain with adequate analgesia remains a challenge, especially for severe pain. Intravenous (IV) morphine protocols are currently indicated. These protocols are based on patient-reported scores, most often after an immediate evaluation of pain intensity at triage. However, they are not systematically prescribed. This aspect could be explained by the fact that physicians individualize opioid pain management for each patient and each care pathway to determine the best benefit-risk balance. Few data are available regarding bedside organizational factors involved in this phenomenon.

Objective

This study aimed to analyze the organizational factors associated with no IV morphine prescription in a standardized context of opioid management in a tertiary-care ED.

Methods

A 3-month prospective study with a case-control design was conducted in a French university hospital ED. This study focused on factors associated with protocol avoidance despite a visual analog scale (VAS) ≥60 or a numeric rating scale (NRS) ≥6 at triage. Pain components, physician characteristics, patient epidemiologic characteristics, and care pathways were considered. Qualitative variables (percentages) were compared using Fisher's exact test or the chi-squared tests. Student's t-test was used to compare continuous variables. The results were expressed as means with their standard deviation (SD). Factors associated with morphine avoidance were identified by logistic regression.

Results

A total of 204 patients were included in this study. A total of 46 cases (IV morphine) and 158 controls (IV morphine avoidance) were compared (3:1 ratio). Pain patterns and patient's epidemiologic characteristics were not associated with an IV morphine prescription. Regarding NRS intervals, the results suggest a practice disconnected from the patient's initial self-report. IV morphine avoidance was significantly associated with care pathways. A significant difference between the IV morphine group and the IV morphine avoidance group was observed for "self-referral" [adjusted odds ratio (aOR): 5.11, 95% CIs: 2.32-12.18, p < 0.0001] and patients' trajectories (Fisher's exact test; p < 0.0001), suggesting IV morphine avoidance in ambulatory pathways. In addition, "junior physician grade" was associated with IV morphine avoidance (aOR: 2.35, 95% CIs: 1.09-5.25, p = 0.03), but physician gender was not.

Conclusion

This bedside case-control study highlights that IV morphine avoidance in the ED could be associated with ambulatory pathways. It confirms the decreased choice of "NRS-only" IV morphine protocols for all patients, including non-trauma patterns. Modern pain education should propose new tools for pain evaluation that integrate the heterogeneity of ED pathways.

Efficacy of opioids for traumatic pain in the emergency department: a systematic review and Bayesian network meta-analysis

Aim: To systematically assess and rank the efficacy of opioid medications for traumatic pain in the emergency department in terms of pain relief, adverse events and rescue analgesia. Methods: Four databases were systematically searched until 26 September 2022: PubMed, Embase, Cochrane Library, and Web of Science. Outcomes were pain relief, adverse events (dizziness, hypotension, pruritus, sedation), and rescue analgesia. For each outcome, network plots were drawn to exhibit direct and indirect comparisons, and rank probabilities were utilized to rank the efficacy of different opioids. Results: Twenty studies of 3,040 patients were eligible for this network meta-analysis. According to the rank probabilities, the top three analgesic medications for pain relief may be sufentanil (78.29% probability of ranking first), buprenorphine (48.54% probability of ranking second) and fentanyl (53.25% probability of ranking third); buprenorphine (31.20%), fentanyl (20.14%) and sufentanil (21.55%) were least likely to cause dizziness; the top three analgesic medications which were least likely to cause hypotension were buprenorphine (81.64%), morphine (45.02%) and sufentanil (17.27%); butorphanol (40.56%), morphine (41.11%) and fentanyl (14.63%) were least likely to cause pruritus; the top three medications which were least likely to cause sedation were hydrocodone + acetaminophen (97.92%), morphine (61.85%) and butorphanol (55.24%); patients who received oxycodone (83.64%), butorphanol (38.31%) and fentanyl (25.91%) were least likely to need rescue analgesia in sequence. Conclusion: Sufentanil, buprenorphine and fentanyl may be superior to other opioid medications in terms of pain relief and the incidence of dizziness, hypotension and pruritus, which might be selected as opioid analgesics for traumatic pain in the emergency setting.

A systematic review of sufentanil for the management of adults with acute pain in the emergency department and pre-hospital setting

BACKGROUND

Pain is commonly encountered in the Emergency Department (ED) and pre-hospital setting and often requires opioid analgesia. We sought to synthesize the available evidence on the effectiveness of sufentanil for acute pain relief for adult patients in the pre-hospital or ED setting.

METHODS

This systematic review was conducted in accordance with PRISMA guidelines. Medline, Embase, Cochrane CENTRAL, and CINAHL were searched from inception to February 1, 2022. The grey literature was also searched. We included randomized controlled trials of adult patients with acute pain who were treated with sufentanil. Two reviewers independently completed screening, full text review, and data extraction. Primary outcome was reduction in pain. Secondary outcomes included adverse events, need for rescue analgesia, and patient and provider satisfaction. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool. A meta-analysis was not performed due to heterogeneity.

RESULTS

Of 1120 unique citations, four studies (3 ED and 1 pre-hospital) met full inclusion criteria (n = 467 participants). The overall quality of the included studies was high. Intranasal (IN) sufentanil was superior to placebo for pain relief at 30 min (difference 20.8%, 95% CI 4.0-36.2%, p = 0.01). Both IN (two studies) and IV sufentanil (one study) were comparable to IV morphine. Mild adverse events were common and there was a higher propensity for minor sedation in patients receiving sufentanil. There were no serious adverse events requiring advanced interventions.

CONCLUSION

Sufentanil was comparable to IV morphine and was superior to placebo for rapid relief of acute pain in the ED setting. The safety profile of sufentanil is similar to IV morphine in this setting, with minimal concern for serious adverse events. The intranasal formulation may provide an alternative, rapid, non-parenteral route that could benefit our unique emergency department and pre-hospital patient population. Due to the overall small sample size of this review, larger studies are required to confirm safety.

Comparison of the Effect of Intravenous Fentanyl with Low-Dose Ketamine on Pain Relief in Patients Taking Methadone and Suffering from Limb Fractures

Background

Given the significance of pain control in addicted patients and the prominence of not using opioids due to patient's drug dependence, the present study aimed at comparing and evaluating the effect of intravenous fentanyl with low-dose ketamine on pain relief in patients taking methadone and suffering from limb fractures.

Materials and Methods

The present double-blind randomized clinical trial was performed on 100 patients taking methadone and suffering from limb fractures. The patients were divided into two groups receiving 1 μg/kg single dose of fentanyl and 0.3 mg/kg single dose of ketamine (low-dose ketamine). Patients' pain scores and the incidence rate of complications were recorded before the intervention, and 15, 30, and 60 min after drug administration and were then compared between the two groups.

Results

The mean pain score of patients 15 min after the intervention was significantly lower in the low-dose ketamine group with a mean of 2.50 ± 1.34 as compared with the fentanyl group with a mean of 7.10 ± 1.43 (P < 0.001). However, the mean pain score was not significantly different between the two groups 30 and 60 min after the intervention (P > 0.05). In addition, the incidence rate of complications was not significantly different between the two groups (P > 0.05).

Conclusion

According to the results of this study, low-dose ketamine as compared with fentanyl relieves pain in the mentioned patients with a faster effect and in a shorter time although no difference can be found between the pain scores of the two groups 30 and 60 min after the intervention.

Opioids for Treatment of Pre-hospital Acute Pain: A Systematic Review

INTRODUCTION

Acute pain is a frequent symptom among patients in the pre-hospital setting, and opioids are the most widely used class of drugs for the relief of pain in these patients. However, the evidence base for opioid use in this setting appears to be weak. The aim of this systematic review was to explore the efficacy and safety of opioid analgesics in the pre-hospital setting and to assess potential alternative therapies.

METHODS

The PubMed, EMBASE, Cochrane Library, Centre for Reviews and Dissemination, Scopus, and Epistemonikos databases were searched for studies investigating adult patients with acute pain prior to their arrival at hospital. Outcomes on efficacy and safety were assessed. Risk of bias for each included study was assessed according to the Cochrane approach, and confidence in the evidence was assessed using the GRADE method.

RESULTS

A total of 3453 papers were screened, of which the full text of 125 was assessed. Twelve studies were ultimately included in this systematic review. Meta-analysis was not undertaken due to substantial clinical heterogeneity among the included studies. Several studies had high risk of bias resulting in low or very low quality of evidence for most of the outcomes. No pre-hospital studies compared opioids with placebo, and no studies assessed the risk of opioid administration for subgroups of frail patients. The competency level of the attending healthcare provider did not seem to affect the efficacy or safety of opioids in two observational studies of very low quality. Intranasal opioids had a similar effect and safety profile as intravenous opioids. Moderate quality evidence supported a similar efficacy and safety of synthetic opioid compared to morphine.

CONCLUSIONS

Available evidence for pre-hospital opioid administration to relieve acute pain is scarce and the overall quality of evidence is low. Intravenous administration of synthetic, fast-acting opioids may be as effective and safe as intravenous administration of morphine. More controlled studies are needed on alternative routes for opioid administration and pre-hospital pain management for potentially more frail patient subgroups.

Hydroxyzine for lowering patient's anxiety during prehospital morphine analgesia: A prospective randomized double blind study

STUDY OBJECTIVE

Hydroxyzine is an antihistamine drug used for symptomatic relief of anxiety and tension. We hypothesized that managing the anxiety of patients with severe pain by adding hydroxyzine to a conventional intravenous morphine titration would relieve their pain more effectively.

METHODS

This was a randomized, double-blind, controlled group study of prehospital patients with acute pain scored greater than or equal to 6 on a 0-10 verbal numeric rating scale (NRS). Patients'anxiety was measured with the self-reported Face Anxiety Scale (FAS) ranking from 0 to 4. The percentage of patients with pain relief (NRS score ≤ 3) 15 min after the first injection was the primary outcome.

RESULTS

One hundred forty patients were enrolled. Fifty-one percent (95% CI 39% to 63%) of hydroxyzine patients versus 52% (95% CI 40% to 64%) of placebo patients reported a pain numeric rating scale score of 3 or lower at 15 min. Ninety-one percent (95% CI 83% to 98%) of patients receiving hydroxyzine reported no more severe anxiety versus 78% (95% CI 68% to 88%) of patients with placebo (p > 0.05). Adverse events were minor, with no difference between groups (6% in hydroxyzine patients and 14% in placebo patients).

CONCLUSION

Addition of hydroxyzine to morphine in the prehospital setting did not reduce pain or anxiety in patients with acute severe pain and therefore is not indicated based on our results.

The Routes of Administration for Acute Postoperative Pain Medication

Effective treatment of postoperative acute pain, together with early mobilization and nutrition, is one of the perioperative strategies advocated to improve surgical outcome and reduce the costs of hospitalization. Moreover, adequate pain control reduces perioperative morbidity related to surgical stress and can also prevent the incidence of chronic postoperative pain syndromes, whose treatment is still a challenge. The choice of the most appropriate analgesics depends not only on the drug class, but also on the most suitable route of administration, the best dosage for that route, and unique limitations and contraindications for every patient. In the present review, a comprehensive analysis was performed on the different routes of administration of acute postoperative pain medications and their indications and limitations, focusing on recent evidence and international recommendations.

Methoxyflurane in Non-Life-Threatening Traumatic Pain-A Retrospective Observational Study

Pain management is a key issue in prehospital trauma. In Switzerland, paramedics have a large panel of analgesic options. Methoxyflurane was recently introduced into Switzerland, and the goal of this study was to describe both the effect of this medication and the satisfaction of its use. This was a retrospective cohort study, performed in one emergency ambulance service. It included adult patients with traumatic pain and a self-assessment of 3 or more on the visual analogue scale or verbal numerical rating scale. The primary outcome was the reduction in pain between the start of the care and the arrival at the hospital. Secondary outcomes included successful analgesia and staff satisfaction. From December 2018 to 4 June to October 2020, 263 patients were included in the study. Most patients had a low prehospital severity score. The median pain at arrival on site was 8 and the overall decrease in pain observed was 4.2 (95% CI 3.9–4.5). Regarding secondary outcomes, almost 60% had a successful analgesia, and over 70% of paramedics felt satisfied. This study shows a reduction in pain, following methoxyflurane, similar to outcomes in other countries, as well as the attainment of a satisfactory level of pain reduction, according to paramedics, with the advantage of including patients in their own care.

Randomised controlled trials in pre-hospital trauma: a systematic mapping review

BACKGROUND

Trauma is a leading cause of morbidity and mortality worldwide with about 5.8 million deaths globally and the leading cause of death in those aged 45 and younger. The pre-hospital phase of traumatic injury is particularly important as care received during this phase has effects on survival. The need for high quality clinical trials in this area has been recognised for several years as a key priority to improve the evidence base and, ultimately, clinical care in prehospital trauma. We aimed to systematically map the existing evidence base for pre-hospital trauma trials, to identify knowledge gaps and inform decisions about the future research agenda.

METHODS

A systematic mapping review was conducted first employing a search of key databases (MEDLINE, CINAHL, EMBASE, and Cochrane Library from inception to March 23rd 2020) to identify randomised controlled trials within the pre-hospital trauma and injury setting. The evidence 'map' identified and described the characteristics of included studies and compared these studies against existing priorities for research. Narrative description of studies informed by analysis of relevant data using descriptive statistics was completed.

RESULTS

Twenty-three eligible studies, including 10,405 participants across 14 countries, were identified and included in the systematic map. No clear temporal or geographical trends in publications were identified. Studies were categorised into six broad categories based on intervention type with evaluations of fluid therapy and analgesia making up 60% of the included trials. Overall, studies were heterogenous with regard to individual interventions within categories and outcomes reported. There was poor reporting across several studies. No studies reported patient involvement in the design or conduct of the trials.

CONCLUSION

This mapping review has highlighted that evidence from trials in prehospital trauma is sparse and where trials have been completed, the reporting is generally poor and study designs sub-optimal. There is a continued need, and significant scope, for improvement in a setting where high quality evidence has great potential to make a demonstrable impact on care and outcomes.

Postoperative analgesia using dezocine alleviates depressive symptoms after colorectal cancer surgery: A randomized, controlled, double-blind trial

BACKGROUND

Postoperative depression is one of the most common mental disorders in patients undergoing cancer surgery and it often delays postoperative recovery. We investigated whether dezocine, an analgesic with inhibitory effect on the serotonin and norepinephrine reuptake, could relieve postoperative depressive symptoms in patients undergoing colorectal cancer surgery.

METHODS

This randomized, controlled, single-center, double-blind trial was performed in the Second Affiliated Hospital of the Army Medical University. A total of 120 patients were randomly assigned to receive either sufentanil (1.3 μg/kg) with dezocine (1 mg/kg) (dezocine group; n = 60) or only sufentanil (2.3 μg/kg) (control group; n = 60) for patient-controlled intravenous analgesia after colorectal cancer surgery. The primary outcome was the Beck Depression Inventory score at 2 days after surgery. The secondary outcomes included the Beck Anxiety Inventory, sleep quality, and quality of recovery scores.

RESULTS

Compared with those in the control group, patients in the dezocine group had lower depression scores (7.3±3.4 vs. 9.9±3.5, mean difference 2.6, 95% CI: 1.4-3.9; P<0.001) at 2 days after surgery and better night sleep quality at the day of surgery (P = 0.010) and at 1 day after the surgery (P<0.001). No significant difference was found in other outcomes between the two groups.

CONCLUSIONS

Intravenous analgesia using dezocine can relieve postoperative depression symptoms and improve sleep quality in patients undergoing colorectal cancer surgery.

Prehospital intravenous fentanyl administered by ambulance personnel: a cluster-randomised comparison of two treatment protocols

Background

Prehospital acute pain is a frequent symptom that is often inadequately managed. The concerns of opioid induced side effects are well-founded. To ensure patient safety, ambulance personnel are therefore provided with treatment protocols with dosing restrictions, however, with the concomitant risk of insufficient pain treatment of the patients. The aim of this study was to investigate the impact of a liberal intravenous fentanyl treatment protocol on efficacy and safety measures.

Methods

A two-armed, cluster-randomised trial was conducted in the Central Denmark Region over a 1-year period. Ambulance stations (stratified according to size) were randomised to follow either a liberal treatment protocol (3 μg/kg) or a standard treatment protocol (2 μg/kg). The primary outcome was the proportion of patients with sufficient pan relief (numeric rating scale (NRS, 0–10) < 3) at hospital arrival. Secondary outcomes included abnormal vital parameters as proxy measures of safety. A multi-level mixed effect logistic regression model was applied.

Results

In total, 5278 patients were included. Ambulance personnel following the liberal protocol administered higher doses of fentanyl [117.7 μg (95% CI 116.7–118.6)] than ambulance personnel following the standard protocol [111.5 μg (95% CI 110.7–112.4), P = 0.0001]. The number of patient with sufficient pain relief at hospital arrival was higher in the liberal treatment group than the standard treatment group [44.0% (95% CI 41.8–46.1) vs. 37.4% (95% CI 35.2–39.6), adjusted odds ratio 1.47 (95% CI 1.17–1.84)]. The relative decrease in NRS scores during transport was less evident [adjusted odds ratio 1.18 (95% CI 0.95–1.48)]. The occurrences of abnormal vital parameters were similar in both groups.

Conclusions

Liberalising an intravenous fentanyl treatment protocol applied by ambulance personnel slightly increased the number of patients with sufficient pain relief at hospital arrival without compromising patient safety. Future efforts of training ambulance personnel are needed to further improve protocol adherence and quality of treatment.

Trial registration

ClinicalTrials.gov (NCT02914678). Date of registration: 26th September, 2016.

Böttiger B, Bouillon B, Fischer M, Gaier G, Gliwitzky B, Helm M, Hilbert-Carius P, Hossfeld B, Meisner C, Schempf B, Wafaisade A, Bernhard M. Analgesia in Patients with Trauma in Emergency Medicine

BACKGROUND

Suitable analgesic drugs and techniques are needed for the acute care of the approximately 18 200-18 400 seriously injured patients in Germany each year.

METHODS

This systematic review and meta-analysis of analgesia in trauma patients was carried out on the basis of randomized, controlled trials and observational studies. A systematic search of the literature over the 10-year period ending in February 2016 was carried out in the PubMed, Google Scholar, and Springer Link Library databases. Some of the considered trials and studies were included in a meta-analysis. Mean differences (MD) of pain reduction or pain outcome as measured on the Numeric Rating Scale were taken as a summarizing measure of treatment efficacy.

RESULTS

Out of 685 studies, 41 studies were considered and 10 studies were included in the meta-analysis. Among the drugs and drug combinations studied, none was clearly superior to another with respect to pain relief. Neither fentanyl versus morphine (MD -0.10 with a 95% confidence interval of [-0.58; 0.39], p = 0.70) nor ketamine versus morphine (MD -1.27 [-3.71; 1.16], p = 0.31), or the combination of ketamine and morphine versus morphine alone (MD -1.23 [-2.29; -0.18], p = 0.02) showed clear superiority regarding analgesia.

CONCLUSION

Ketamine, fentanyl, and morphine are suitable for analgesia in spontaneously breathing trauma patients. Fentanyl and ketamine have a rapid onset of action and a strong analgesic effect. Our quantitative meta-analysis revealed no evidence for the superiority of any of the three substances over the others. Suitable monitoring equipment, and expertise in emergency procedures are prerequisites for safe and effective analgesia by healthcare professionals..

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.

Review on pharmacological pain management in trauma patients in (pre-hospital) emergency medicine in the Netherlands

Pain is one of the main complaints of trauma patients in (pre-hospital) emergency medicine. Significant deficiencies in pain management in emergency medicine have been identified. No evidence-based protocols or guidelines have been developed so far, addressing effectiveness and safety issues, taking the specific circumstances of pain management of trauma patients in the chain of emergency care into account. The aim of this systematic review was to identify effective and safe initial pharmacological pain interventions, available in the Netherlands, for trauma patients with acute pain in the chain of emergency care. Up to December 2011, a systematic search strategy was performed with MeSH terms and free text words, using the bibliographic databases CINAHL, PubMed and Embase. Methodological quality of the articles was assessed using standardized evaluation forms. Of a total of 2328 studies, 25 relevant studies were identified. Paracetamol (both orally and intravenously) and intravenous opioids (morphine and fentanyl) proved to be effective. Non-steroidal anti-inflammatory drugs (NSAIDs) showed mixed results and are not recommended for use in pre-hospital ambulance or (helicopter) emergency medical services [(H)EMS]. These results could be used for the development of recommendations on evidence-based pharmacological pain management and an algorithm to support the provision of adequate (pre-hospital) pain management. Future studies should address analgesic effectiveness and safety of various drugs in (pre-hospital) emergency care. Furthermore, potential innovative routes of administration (e.g., intranasal opioids in adults) need further exploration.

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.

Nitrous oxide for early analgesia in the emergency setting: a randomized, double-blind multicenter prehospital trial

OBJECTIVES

Although 50% nitrous oxide (N(2) O) and oxygen is a widely used treatment, its efficacy had never been evaluated in the prehospital setting. The objective of this study was to demonstrate the efficacy of premixed N(2) O and oxygen in patients with out-of-hospital moderate traumatic acute pain.

METHODS

This prospective, randomized, multicenter, double-blind trial enrolled patients with acute moderate pain (numeric rating scale [NRS] score between 4 and 6 out of 10) caused by trauma. Patients were assigned to receive either 50/50 N(2) O and oxygen 9 L/min (N(2) O group) or medical air (MA) 9 L/min (MA group), in ambulances from two nurse-staffed fire department centers. After the first 15 minutes, every patient received N(2) O and oxygen. The primary endpoint was pain relief at 15 minutes (T15), defined as a NRS ≤ 3 of 10. The NRS was measured every 5 minutes. Secondary endpoints were treatment safety and adverse events, time to analgesia, and patient and investigator satisfaction with analgesia.

RESULTS

Sixty patients were included with no differences between groups in age (median = 34 years, interquartile range [IQR] = 23 to 53 years), sex (37 males, 66%), and initial median NRS of 6 (IQR = 5 to 6). At T15, 67% of the patients in the N(2) O group had an NRS score of 3 or lower versus 27% of those in the MA group (delta = 40%, 95% confidence interval [CI] = 17% to 63%; p < 0.001). The median pain scores were lower in the N(2) O group at T15, 2 (IQR = 1 to 4) versus 5 (IQR = 3 to 6). There was a difference at 5 minutes that persisted at all subsequent time points. Four patients (one in the N(2) O group) experienced adverse events (nausea) during the protocol.

CONCLUSIONS

This study demonstrates the efficacy of N(2) O for the treatment of pain from acute trauma in adults in the prehospital setting.

The 90% effective dose of a sufentanil bolus for the management of painful positioning in intubated patients in the ICU

CONTEXT

Pain and discomfort arising from the routine care of intubated patients in the ICU is managed by continuous infusion of narcotic and sedative drugs. There is benefit in keeping infusion rates low because lightening sedation improves clinical outcome, but this risks breakthrough pain. Management of this discomfort by bolus administration could permit lower background infusion rates, but the lowest effective bolus dose of sufentanil to achieve this is unknown.

OBJECTIVE

The aim of this study was to determine the effective analgesic dose in 90% of intubated patients (ED90) in the ICU given bolus sufentanil. Pain was assessed using a Behavioural Pain Scale (BPS) requiring a score of 3-4 during moving to the lateral decubitus position.

DESIGN

Prospective, dose response study.

SETTING

A 16-bed multidisciplinary ICU in a French university hospital. Study period was from January to June 2010.

PATIENTS

Intubated and ventilated patients were eligible for the study once they had reached a BPS of 3 or 4 and Ramsay score of 3-5 within 48 h of admission to the ICU.

INTERVENTION

The analgesic efficacy of a sufentanil bolus was measured during successive lateral decubitus positioning over a 72-h study period, using the BPS scale. The dose was increased with each subsequent turn to lateral decubitus until a BPS score of 3-4 was obtained (dose escalation, starting at zero).

MAIN OUTCOME MEASURES

BPS, Ramsay score, heart rate and mean arterial pressure were collected before and during each procedure.

RESULTS

A total of 25 patients were enrolled over 6 months. The ED90 bolus for sufentanil was 0.15 μg kg, but 40% of the patients subsequently demonstrated increased BPS with this dose.

CONCLUSION

The effective dose in 90% was 0.15 μg kg during the first 5 days of sedation. There were no adverse effects. A pre-emptive sufentanil bolus can be used to treat anticipated pain in the ICU. Regular and frequent assessments of acute pain and sedation are essential for adjusting the dose, on a case-by-case basis. This strategy may help clinicians to keep background infusions of sedatives and narcotics as low as possible and may improve clinical outcome.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01356732.

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.