Efficacy of prescribed opioids for acute pain after being discharged from the emergency department: A systematic review and meta-analysis.

BACKGROUND: Opioids are often prescribed for acute pain to patients discharged from the emergency department (ED), but there is a paucity of data on their short-term use. The purpose of this study was to synthesize the evidence regarding the efficacy of prescribed opioids compared to nonopioid analgesics for acute pain relief in ED-discharged patients. METHODS: MEDLINE, EMBASE, CINAHL, PsycINFO, CENTRAL, and gray literature databases were searched from inception to January 2023. Two independent reviewers selected randomized controlled trials investigating the efficacy of prescribed opioids for ED-discharged patients, extracted data, and assessed risk of bias. Authors were contacted for missing data and to identify additional studies. The primary outcome was the difference in pain intensity scores or pain relief. All meta-analyses used a random-effect model and a sensitivity analysis compared patients treated with codeine versus those treated with other opioids. RESULTS: From 5419 initially screened citations, 46 full texts were evaluated and six studies enrolling 1161 patients were included. Risk of bias was low for five studies. There was no statistically significant difference in pain intensity scores or pain relief between opioids versus nonopioid analgesics (standardized mean difference [SMD] 0.12; 95% confidence interval [CI] -0.10 to 0.34). Contrary to children, adult patients treated with opioid had better pain relief (SMD 0.28, 95% CI 0.13-0.42) compared to nonopioids. In another sensitivity analysis excluding studies using codeine, opioids were more effective than nonopioids (SMD 0.30, 95% CI 0.15-0.45). However, there were more adverse events associated with opioids (odds ratio 2.64, 95% CI 2.04-3.42). CONCLUSIONS: For ED-discharged patients with acute musculoskeletal pain, opioids do not seem to be more effective than nonopioid analgesics. However, this absence of efficacy seems to be driven by codeine, as opioids other than codeine are more effective than nonopioids (mostly NSAIDs). Further prospective studies on the efficacy of short-term opioid use after ED discharge (excluding codeine), measuring patient-centered outcomes, adverse events, and potential misuse, are needed.

Clinical outcomes following out-of-hospital cardiac arrest: The minute-by-minute impact of bystander cardiopulmonary resuscitation.

AIMS: The time-dependent prognostic role of bystander cardiopulmonary resuscitation (CPR) for out-of-hospital cardiac arrest (OHCA) patients has not been described with great precision, especially for neurologic outcomes. Our objective was to assess the association between bystander CPR, emergency medical service (EMS) response time, and OHCA patients' outcomes. METHODS: This cohort study used the Resuscitation Outcomes Consortium Cardiac Epidemiologic Registries. Bystander-witnessed adult OHCA treated by EMS were included. The primary outcome was survival to hospital discharge and secondary outcome was survival with a good neurologic outcome (modified Rankin scale 0-2). Multivariable logistic regression models were used to assess the associations and interactions between bystander CPR, EMS response time and clinical outcomes. RESULTS: Out of 229,637 patients, 41,012 were included (18,867 [46.0%] without bystander CPR and 22,145 [54.0%] with bystander CPR). Bystander CPR was independently associated with higher survival (adjusted odds ratio [AOR] = 1.70 [95%CI 1.61-1.80]) and survival with a good neurologic outcome (AOR = 1.87 [95%CI 1.70-2.06]), while longer EMS response times were independently associated with lower survival to hospital discharge (each additional minute of EMS response time: AOR = 0.92 [95%CI 0.91-0.93], p < 0.001) and lower survival with a good neurologic outcome (AOR = 0.88 [95%CI 0.86-0.89], p < 0.001). There was no interaction between bystander CPR and EMS response time's association with survival (p = 0.12) and neurologic outcomes (p = 0.65). CONCLUSIONS: Although bystander CPR is associated with an immediate increase in odds of survival and of good neurologic outcome for OHCA patients, it does not influence the negative association between longer EMS response time and survival and good neurologic outcome.

Association of Initial Pulseless Electrical Activity Heart Rate and Clinical Outcomes following Adult Non-Traumatic Out-of-Hospital Cardiac Arrest.

OBJECTIVE: Studies evaluating the prognostic value of the pulseless electrical activity (PEA) heart rate in out-of-hospital cardiac arrest (OHCA) patients have reported conflicting results. The objective of this study was to evaluate the association between the initial PEA heart rate and favorable clinical outcomes for OHCA patients. METHODS: The present post-hoc cohort study used the Resuscitation Outcomes Consortium Cardiac Epidemiologic Registry Version 3, which included OHCA patients in seven US and three Canadian sites from April 2011 to June 2015. The primary outcome was survival to hospital discharge and the secondary outcome was survival with a good functional outcome. For the primary analysis, the patients were separated into eight groups according to their first rhythms and PEA heart rates: (1) initial PEA heart rate of 1-20 beats per minute (bpm); (2) 21-40 bpm; (3) 41-60 bpm; (4) 61-80 bpm; (5) 81-100 bpm; (6) 101-120 bpm; (7) over 120 bpm; (8) initial shockable rhythm (reference category). Multivariable logistic regression models were used to assess the associations of interest. RESULTS: We identified 17,675 patients (PEA: 7,089 [40.1%]; initial shockable rhythm: 10,797 [59.9%]). Patients with initial PEA electrical frequencies ≤100 bpm were less likely to survive to hospital discharge than patients with initial shockable rhythms (1-20 bpm: adjusted odds ratio [AOR] = 0.15 [95%CI 0.11-0.21]; 21-40 bpm: AOR = 0.21 [0.18-0.25]; 41-60 bpm: AOR = 0.30 [0.25-0.36]; 61-80 bpm: AOR = 0.37 [0.28-0.49]; 81-100 bpm: AOR = 0.55 [0.41-0.65]). However, there were no statistical outcome differences between PEA patients with initial electrical frequencies of >100 bpm and patients with initial shockable rhythms (101-120 bpm: AOR = 0.65 [95%CI 0.42-1.01]; >120 bpm: AOR = 0.72 [95%CI 0.37-1.39]). Similar results were observed for survival with good functional outcomes (101-120 bpm: AOR = 0.60 [95%CI 0.31-1.15]; >120 bpm: AOR = 1.08 [95%CI 0.50-2.28]). CONCLUSIONS: We observed a good association between higher initial PEA electrical frequency and favorable clinical outcomes for OHCA patients. As there is no significant difference in outcomes between patients with initial PEA heart rates of more than 100 bpm and those with initial shockable rhythms, we can hypothesize that these patients could be considered in the same prognostic category.

Accuracy of the Initial Rhythm to Predict a Short No-Flow Time in Out-of-Hospital Cardiac Arrest.

OBJECTIVES: The no-flow time (NFT) can help establish prognosis in out-of-hospital cardiac arrest (OHCA) patients. It is often used as a selection criterion for extracorporeal resuscitation. In patients with an unwitnessed OHCA for whom the NFT is unknown, the initial rhythm has been proposed to identify those more likely to have had a short NFT. Our objective was to determine the predictive accuracy of an initial shockable rhythm for an NFT of 5 minutes or less (NFT ≤ 5). DESIGN: Retrospective analysis of prospectively collected data. SETTING: Prehospital OHCA in eight U.S. and three Canadian sites. PATIENTS: A total of 28,139 adult patients with a witnessed nontraumatic OHCA were included, of whom 11,228 (39.9%) experienced an emergency medical service-witnessed OHCA (NFT = 0), 695 (2.7%) had a bystander-witnessed OHCA, and an NFT less than or equal to 5, and 16,216 (57.6%) with a bystander-witnessed OHCA and an NFT greater than 5. INTERVENTIONS: Sensitivity, specificity, and likelihood ratios of an initial shockable rhythm to identify patients with an NFT less than or equal to 5 minutes. MEASUREMENTS AND MAIN RESULTS: The sensitivity of an initial shockable rhythm to identify patients with an NFT less than or equal to 5 was poor (25% [95% CI, 25-26]), but specificity was moderate (70% [95% CI, 69-71]). The positive and likelihood ratios were inverted (negative accuracy) (positive likelihood ratio, 0.76 [95% CI, 0.74-0.79]; negative likelihood ratio, 1.12 [95% CI, 1.10-1.12]). Including only patients with a bystander-witnessed OHCA improved the sensitivity to 48% (95% CI, 45-52), the positive likelihood ratio to 1.45 (95% CI, 1.33-1.58), and the negative likelihood ratio to 0.77 (95% CI, 0.72-0.83), while slightly lowering the specificity to 67% (95% CI, 66-67). CONCLUSIONS: Our analysis demonstrated that the presence of a shockable rhythm at the time of initial assessment was poorly sensitive and only moderately specific for OHCA patients with a short NFT. The initial rhythm, therefore, should not be used as a surrogate for NFT in clinical decision-making.

Safety assessment of a redirection program using an electronic application for low-acuity patients visiting an emergency department.

BACKGROUND: Emergency departments (EDs) are operating at or above capacity, which has negative consequences on patients in terms of quality of care and morbi-mortality. Redirection strategies for low-acuity ED patients to primary care practices are usually based on subjective eligibility criteria that sometimes necessitate formal medical assessment. Literature investigating the effect of those interventions is equivocal. The aim of the present study was to assess the safety of a redirection process using an electronic clinical support system used by the triage nurse without physician assessment. METHODS: A single cohort observational study was performed in the ED of a level 1 academic trauma center. All low-acuity patients redirected to nearby clinics through a clinical decision support system (February-August 2017) were included. This system uses different sets of medical prerequisites to identify patients eligible to redirection. Data on safety and patient experience were collected through phone questionnaires on day 2 and 10 after ED visit. The primary endpoint was the rate of redirected patients returning to any ED for an unexpected visit within 48 h. Secondary endpoints were the incidence of 7-day return visit and satisfaction rates. RESULTS: A total of 980 redirected low-acuity patients were included over the period: 18 patients (2.8%) returned unexpectedly to an ED within 48 h and 31 patients (4.8%) within 7 days. No hospital admission or death were reported within 7 days following the first ED visit. Among redirected patients, 81% were satisfied with care provided by the clinic staff. CONCLUSION: The implementation of a specific electronic-guided decision support redirection protocol appeared to provide safe deferral to nearby clinics for redirected low-acuity patients. EDs are pivotal elements of the healthcare system pathway and redirection process could represent an interesting tool to improve the care to low-acuity patients.

Electrical rhythm degeneration in adults with out-of-hospital cardiac arrest according to the no-flow and bystander low-flow time.

AIMS: For out-of-hospital cardiac arrest (OHCA) patients, the influence of the delay before the initiation of resuscitation, termed the no-flow time (NFT), and duration of bystander-only resuscitation low-flow time (BLFT) on the type of electrical rhythm observed has not been well described. The objective of this study is to determine the relationship between NFT, BLFT and the likelihood of a shockable rhythm over time. METHODS: Using a North American prospective registry (2005-2015; mostly urban settings), we selected adult (18 years and over) patients who experienced a witnessed OHCA from a suspected cardiac etiology. Patients with an emergency medical services witnessed OHCA were only included in sensitivity analyses. The association between the NFT, BLFT and the presence of a shockable rhythm was evaluated using a multivariable logistic regression adjusting for the registry version, age, sex, and public location. RESULTS: A total of 229,632 patients were logged in the registry, 50,957 of whom were included. Of these, 17,704 (34.7%) had an initial shockable rhythm. After the first minute, a significant decrease over time in the occurrence of shockable rhythm is observed but is slower when bystander cardiopulmonary resuscitation (CPR) is provided (each supplemental minute of BLFT: adjusted odds ratio = 0.95, 95 %CI = 0.94-0.95; each supplemental minute of NFT: adjusted odds ratio = 0.91, 95 %CI = 0.90-0.91]). CONCLUSIONS: In this large observational study, we were able to demonstrate that longer NFT were associated with lower odds of shockable presenting rhythms. Bystander CPR significantly mitigates the degradation of shockable rhythms over time, strengthening the need to improve bystander CPR rates around the world.

Opioid and non-opioid pain relief after an emergency department acute pain visit.

OBJECTIVES: Treatment of acute pain after emergency department (ED) discharge remains a challenge in the opioid crisis context. Our objective was to determine the proportion of patients using opioid vs non-opioid pain medication following discharge from the ED with acute pain, and the association of type of pain medication with average pain intensity before pain medication intake and report of pain relief. METHODS: This was a prospective cohort study of ED patients aged ≥ 18 years with an acute pain (≤ 2 weeks) who were discharged with an opioid prescription. Patients completed a 14-day diary assessing daily pain intensity level before each pain medication intake (0-10 numeric rating scale), type of pain medication use (opioid vs non-opioid), and if pain was relieved by the medication used that day. Multilevel analyses were used to compare the effect of type of analgesic used on pain intensity and relief. RESULTS: A total of 381 participants completed the 14-day diary; 50% were women and median age was 54 years (IQR = 43-66). Average daily pain intensity before pain medication intake was significantly higher for patients who used opioids (5.9; 95% CI 5.7-6.2) as compared to non-opioid analgesics (4.2; 95% CI 4.0-4.5) or no pain medication (2.2; 95% CI 1.9-2.5). Controlling for pain intensity, patients using opioids were more likely to report a pain relief (OR = 1.3; 95% CI 1.1-1.8) as compared to those who used non-opioid analgesics. CONCLUSION: Overall, opioids appear to be effective and used as intended by the prescribing physician.

RéSUMé: OBJECTIFS: Le traitement de la douleur aiguë après la sortie des départements d'urgence (DU) reste un défi dans le contexte de la crise des opioïdes. Notre objectif était de déterminer la proportion de patients utilisant des analgésiques opioïdes par rapport aux analgésiques non opioïdes après leur sortie des urgences avec une douleur aiguë, et l'association du type d'analgésique avec l'intensité moyenne de la douleur avant la prise d'analgésiques et le soulagement de la douleur rapporté. LES MéTHODES: Il s'agissait d'une étude de cohorte prospective de patients (DU) âgés de ≥18 ans souffrant de douleurs aiguës (≤ 2 semaines) et ayant reçu une ordonnance d'opioïdes à leur sortie de l'hôpital. Les patients ont rempli un journal de 14 jours évaluant le niveau d'intensité de la douleur quotidienne avant chaque prise de médicaments anti-douleur (échelle d'évaluation numérique de 0 à 10), le type d'utilisation des médicaments anti-douleur (opioïdes contre non opioïdes), et si la douleur était soulagée par les médicaments utilisés ce jour-là. Des analyses multiniveaux ont été utilisées pour comparer l'effet du type d'analgésique utilisé sur l'intensité et le soulagement de la douleur. RéSULTATS: Au total, 381 participants ont rempli le journal de 14 jours; 50% étaient des femmes et l'âge médian était de 54 ans (EI = 43­66). L'intensité moyenne de la douleur quotidienne avant la prise d'analgésiques était significativement plus élevée chez les patients qui prenaient des opioïdes (5.9; 95% IC: 5.7­6.2) par rapport aux analgésiques non opioïdes (4.2; 95% IC: 4.0­4.5) ou à l'absence d'analgésiques (2.2; 95% IC: 1.9­2.5). En contrôlant l'intensité de la douleur, les patients utilisant des opioïdes étaient plus susceptibles de déclarer un soulagement de la douleur (OR = 1.3; 95% CI: 1.1−1.8) par rapport à ceux qui utilisaient des analgésiques non opioïdes. CONCLUSION: Dans l'ensemble, les opioïdes semblent être efficaces et utilisés comme prévu par le médecin prescripteur.

Oxygen Therapy and Risk of Infection for Health Care Workers Caring for Patients With Viral Severe Acute Respiratory Infection: A Systematic Review and Meta-analysis.

STUDY OBJECTIVE: To synthesize the evidence regarding the infection risk associated with different modalities of oxygen therapy used in treating patients with severe acute respiratory infection. Health care workers face significant risk of infection when treating patients with a viral severe acute respiratory infection. To ensure health care worker safety and limit nosocomial transmission of such infection, it is crucial to synthesize the evidence regarding the infection risk associated with different modalities of oxygen therapy used in treating patients with severe acute respiratory infection. METHODS: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched from January 1, 2000, to April 1, 2020, for studies describing the risk of infection associated with the modalities of oxygen therapy used for patients with severe acute respiratory infection. The study selection, data extraction, and quality assessment were performed by independent reviewers. The primary outcome measure was the infection of health care workers with a severe acute respiratory infection. Random-effect models were used to synthesize the extracted data. RESULTS: Of 22,123 citations, 50 studies were eligible for qualitative synthesis and 16 for meta-analysis. Globally, the quality of the included studies provided a very low certainty of evidence. Being exposed or performing an intubation (odds ratio 6.48; 95% confidence interval 2.90 to 14.44), bag-valve-mask ventilation (odds ratio 2.70; 95% confidence interval 1.31 to 5.36), and noninvasive ventilation (odds ratio 3.96; 95% confidence interval 2.12 to 7.40) were associated with an increased risk of infection. All modalities of oxygen therapy generate air dispersion. CONCLUSION: Most modalities of oxygen therapy are associated with an increased risk of infection and none have been demonstrated as safe. The lowest flow of oxygen should be used to maintain an adequate oxygen saturation for patients with severe acute respiratory infection, and manipulation of oxygen delivery equipment should be minimized.

Relationship between acute pain trajectories after an emergency department visit and chronic pain: a Canadian prospective cohort study.

OBJECTIVES: Inadequate acute pain management can reduce the quality of life, cause unnecessary suffering and can often lead to the development of chronic pain. Using group-based trajectory modelling, we previously identified six distinct pain intensity trajectories for the first 14-day postemergency department (ED) discharge; two linear ones with moderate or severe pain during follow-up (~40% of the patients) and four cubic polynomial order trajectories with mild or no pain at the end of the 14 days (low final pain trajectories). We assessed if previously described acute pain intensity trajectories over 14 days after ED discharge are predictive of chronic pain 3 months later. DESIGN: Prospective cohort study. SETTING: Tertiary care trauma centre academic hospital. PARTICIPANTS: This study included 18 years and older ED patients who consulted for acute (≤2 weeks) pain conditions that were discharged with an opioid prescription. Patients completed a 14-day diary in which they listed their daily pain intensity (0-10 numeric rating scale). OUTCOMES: Three months after ED visit, participants were questioned by phone about their current pain intensity (0-10 numeric rating scale). Chronic pain was defined as patients with current pain intensity ≥4 at 3 months. RESULTS: A total of 305 participants remained in the study at 3 months, 49% were women and a mean age of 55±15 years. Twelve per cent (11.9; 95% CI 8.2 to 15.4) of patients had chronic pain at the 3-month follow-up. Controlling for age, sex and pain condition, patients with moderate or severe pain trajectories and those with only a severe pain trajectory were respectively 5.1 (95% CI 2.2 to 11.8) and 8.2 (95% CI 3.4 to 20.0) times more likely to develop chronic pain 3 months later compared with patients in the low final pain trajectories. CONCLUSION: Specific acute pain trajectories following an ED visit are closely related to the development of chronic pain 3 months later. TRIAL REGISTRATION NUMBER: NCT02799004; Results.

Can the "important brain injury criteria" predict neurosurgical intervention in mild traumatic brain injury? A validation study.

BACKGROUND: There is variability in the management of patients presenting to the emergency department (ED) with mild traumatic brain injury (MTBI) and abnormal findings on their initial head computed tomography (CT). The main objective of this study was to validate the value of the Important Brain Injury (IBI) criteria, introduced by the Canadian CT-Head Rule, in predicting the need for surgical intervention. The secondary objective was to identify independent predictors for neurosurgical intervention. METHODS: This is a post hoc analysis of a prospective cohort of adult patients presenting to the ED of one tertiary care, academic center, between 2008 and 2012, with MTBI and an abnormal initial head CT. Neurosurgical intervention was at the discretion of the treating physician. The sensitivity and specificity of the IBI criteria were calculated with 95% confidence intervals (CI95%). A multivariate logistic regression model was used to identify independent predictors for neurosurgical intervention with the direct entry method. RESULTS: A total of 678 patients (male = 65.9%, mean age = 62.5 years) were included, of whom 114 (16.8%) required neurosurgical intervention. All patients requiring neurosurgical intervention met IBI criteria on their initial head CT (sensitivity of 100% [CI95% 96.8-100]). However, 368 (65.2%) patients with findings of IBI did not require neurosurgical intervention (specificity of 34.8% [CI95% 30.8-38.8]). Age over 65 was independently associated with neurosurgical intervention in the IBI population. CONCLUSION: The IBI criteria for MTBI identified all patients who required neurosurgical intervention; however its specificity is low.

Side effects from opioids used for acute pain after emergency department discharge.

OBJECTIVE: Opioid side effects are common when treating chronic pain. However, the frequency of opioid side effects has rarely been examined in acute pain conditions, particularly in a post emergency department (ED) setting. The objective of this study was to evaluate the short-term incidence of opioid-induced side effects (constipation, nausea/vomiting, dizziness, drowsiness, sweating, and weakness) in patients discharged from the ED with an opioid prescription. METHODS: This is a prospective cohort study of patients aged ≥18 years who visited the ED for an acute pain condition (≤2 weeks) and were discharged with an opioid prescription. Patients completed a 14-day diary assessing daily pain medication use and side effects. RESULTS: We recruited 386 patients with a median age of 54 years (IQR:43-66); 50% were women. During the 2-week follow-up, 80% of patients consumed opioids. Among the patients who used opioids, 79% (95%CI:75-83) reported side effects compared to 38% (95%CI:27-49) for non-users. Adjusting for age, sex, and pain condition, patients who used opioids were more likely to report constipation (OR:7.5; 95%CI:3.1-17.9), nausea/vomiting (OR:4.1; 95%CI:1.8-9.5), dizziness (OR:5.4; 95%CI: 2.2-13.2), drowsiness (OR:4.6; 95%CI:2.5-8.7), and weakness (OR:4.2; 95%CI:1.6-11.0) compared to non-users. A dose-response trend was observed for constipation but not for the other side effects. Nausea/vomiting (OR:2.0; 95%CI:1.1-3.6) and dizziness (OR:1.9; 95%CI:1.1-3.4) were more often associated with oxycodone than with morphine. CONCLUSION: As observed for chronic pain treatment, side effects are highly prevalent during short-term opioid treatment for acute pain. Physicians should inform patients about those side effects and should consider prescribing laxatives.

Opioid Use and Misuse Three Months After Emergency Department Visit for Acute Pain.

BACKGROUND: Studies evaluating long-term prescription opioid use are retrospective and based on filled opioid prescriptions from governmental databases. These studies cannot evaluate if opioids were really consumed and are unable to differentiate if they were used for a new pain or chronic pain or were misused. The aim of this study was to assess opioid use rate and reasons for consuming 3 months after being discharged from the emergency department (ED) with an opioid prescription. METHODS: This is a prospective cohort study conducted in the ED of a tertiary care urban center with a convenience sample of discharged patients ≥ 18 years who consulted for an acute pain condition (≤2 weeks). Three months post-ED visit, participants were interviewed by phone on their past 2-week opioid consumption and their reasons for consuming: a) for pain related to the initial ED visit, b) for a new unrelated pain, or c) for another reason. RESULTS: Of the 524 participants questioned at 3 months (mean ± SD age = 51 ± 16 years, 47% women), 47 patients (9%, 95% confidence interval [CI] = 7%-12%) reported consuming opioids in the previous 2 weeks. Among those, 34 (72%) reported using opioids for their initial pain, nine (19%) for a new unrelated pain and four (9%) for another reason (0.8%, 95% CI = 0.3%-2.0%, of the whole cohort). Patients who used opioids during the 2 weeks after the ED visit were 3.8 (95% CI = 1.2-12.7) times more likely to consume opioids at 3 months. CONCLUSION: Opioid use at the 3-month follow-up in ED patients discharged with an opioid prescription for an acute pain condition is not necessarily associated with opioid misuse; 91% of those patients consumed opioids to treat pain. Of the whole cohort, less than 1% reported using opioids for reasons other than pain. The rate of long-term opioid use reported by prescription-filling database studies should not be viewed as a proxy for incidence of opioid misuse.

Acute Pain Resolution After an Emergency Department Visit: A 14-Day Trajectory Analysis.

STUDY OBJECTIVE: The objective of the study is to evaluate the acute pain intensity evolution in emergency department (ED) discharged patients, using group-based trajectory modeling. This method identifies patient groups with similar profiles of change over time without assuming the existence of a particular pattern or number of groups. METHODS: This was a prospective cohort study of ED patients aged 18 years or older, with an acute pain condition (≤2 weeks), and discharged with an opioid prescription. Patients completed a 14-day diary assessing daily pain intensity level (numeric rating scale of 0 to 10) and pain medication use. RESULTS: Among the 372 included patients, 6 distinct post-ED pain intensity trajectories were identified. Two started with severe levels of pain; one remained with severe pain intensity (12.6% of the sample) and the other ended with a moderate pain intensity level (26.3%). Two other trajectories had severe initial pain; one decreased to mild pain (21.7%) and the other to no pain (13.8%). Another trajectory had moderate initial pain that decreased to a mild level (15.9%) and the last one started with mild pain intensity and had no pain at the end of the 14-day period (9.7%). The pain trajectory patterns were significantly associated with age, type of painful conditions, pain intensity at ED discharge, and opioid consumption. CONCLUSION: Acute pain resolution after an ED visit seems to progress through 6 different trajectory patterns that are more informative than simple linear models and could be useful to adapt acute pain management in future research.