Association of Opioids and Sedatives with Increased Risk of In-Hospital Cardiopulmonary Arrest from an Administrative Database

Is General Anesthesia for Peripheral Vascular Surgery Correlated with Impaired Outcome in Patients with Cardiac Comorbidity? A Closer Look into the Nationwide Danish Cohort

OBJECTIVE

General anesthesia (GA) may impair outcome after vascular surgery. The use of anticoagulant medication is often used in patients with cardiac comorbidity. Regional anesthesia (RA) requires planning of discontinuation before neuraxial blockade(s) in this subgroup. This study aimed to describe the effect of anesthesia choice on outcome after vascular surgery in patients with known cardiac comorbidity.

DESIGN

Retrospective cohort study.

SETTING

Danish hospitals.

PARTICIPANTS

6302 patients with known cardiac comorbidity, defined as ischemic heart disease, valve disease, pulmonary vascular disease, heart failure, and cardiac arrhythmias, undergoing lower extremity vascular surgery between 2005 and 2017.

INTERVENTIONS

GA versus RA.

MEASUREMENTS AND MAIN RESULTS

Data were extracted from national registries. GA was defined as anesthesia with mechanical ventilation. Multivariable regression models were used to describe the incidence of postoperative complications as well as 30-day mortality, hypothesizing that better outcomes would be seen after RA. The rate of RA decreased from 48% in 2005 to 20% in 2017. The number of patients with 1 or more complications was 9.7% vs 6.2% (p < 0.001), and 30-day mortality was 6.0% vs 3.4% (p < 0.001) after GA. After adjusting for baseline differences, the odds ratio (OR) was significantly lower for medical complications (cardiac, pulmonary, renal, new dialysis, intensive care unit and other medical complications; OR, 0.97; 95% confidence interval [CI], 0.95-0.98) and 30-day mortality (OR 0.98; 95% CI, 0.97-0.99) after RA.

CONCLUSIONS

RA may be associated with a better outcome than GA after lower extremity vascular surgery in patients with a cardiac comorbidity. Prioritizing RA, despite the inconvenience of discontinuing anticoagulants, may be recommended.

Population study of pupillary unrest in ambient light

INTRODUCTION

Pupillary unrest in ambient light (PUAL) describes the fluctuation of pupil diameter observed in normal, awake subjects under typical levels of indoor light. PUAL becomes low to absent in young healthy subjects during opioid intoxication. We sought to determine the age-related distribution of PUAL values in a random sample of ambulatory participants.

METHODS

Subjects ≥18 years of age were recruited. All were identified by age range (18-29, 30-49, 50-69, and ≥70), and surveyed for diabetes, beta-blocker use, and prior 24-hour opioid use. Relationship between mean PUAL, age group, comorbidity and opioid use were examined by Kruskal Wallis test, and PUAL and was modeled using stepwise multilevel linear regression, including diabetes, beta blocker use, prior 24-hour opioid use, autonomic dysfunction, and pupil diameter as fixed effects and subject as random effect.

RESULTS

Among 150 subjects, 17 reported diabetes, 12 reported beta-blocker use, 14 reported prior 24-hour opioid use, and 120 reported no comorbid conditions. PUAL declined in higher age categories (by 0.0307, P < 0.001), with diabetes (by 0.0481, P = 0.025), and with beta-blocker use (by 0.0616, P = 0.005). Opioid related PUAL decline was observed, but statistical significance varied by model. Among healthy subjects, no PUAL value fell within range indicating high likelihood of opioid toxicity based on previous data from healthy subjects undergoing opioid infusion.

CONCLUSION

PUAL declined in higher age groups, diabetes and beta-blocker use, conditions associated with impaired autonomic function, and with opioid use but significance varied depending on the chosen model.

2024 RECOVER Guidelines: Advanced Life Support. Evidence and knowledge gap analysis with treatment recommendations for small animal CPR

OBJECTIVE

To systematically review the evidence and devise clinical recommendations on advanced life support (ALS) in dogs and cats and to identify critical knowledge gaps.

DESIGN

Standardized, systematic evaluation of literature pertinent to ALS following Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Prioritized questions were each reviewed by Evidence Evaluators, and findings were reconciled by ALS Domain Chairs and Reassessment Campaign on Veterinary Resuscitation (RECOVER) Co-Chairs to arrive at treatment recommendations commensurate to quality of evidence, risk:benefit relationship, and clinical feasibility. This process was implemented using an Evidence Profile Worksheet for each question that included an introduction, consensus on science, treatment recommendations, justification for these recommendations, and important knowledge gaps. A draft of these worksheets was distributed to veterinary professionals for comment for 4 weeks prior to finalization.

SETTING

Transdisciplinary, international collaboration in university, specialty, and emergency practice.

RESULTS

Seventeen questions pertaining to vascular access, vasopressors in shockable and nonshockable rhythms, anticholinergics, defibrillation, antiarrhythmics, and adjunct drug therapy as well as open-chest CPR were reviewed. Of the 33 treatment recommendations formulated, 6 recommendations addressed the management of patients with nonshockable arrest rhythms, 10 addressed shockable rhythms, and 6 provided guidance on open-chest CPR. We recommend against high-dose epinephrine even after prolonged CPR and suggest that atropine, when indicated, is used only once. In animals with a shockable rhythm in which initial defibrillation was unsuccessful, we recommend doubling the defibrillator dose once and suggest vasopressin (or epinephrine if vasopressin is not available), esmolol, lidocaine in dogs, and/or amiodarone in cats.

CONCLUSIONS

These updated RECOVER ALS guidelines clarify the approach to refractory shockable rhythms and prolonged CPR. Very low quality of evidence due to absence of clinical data in dogs and cats continues to compromise the certainty with which recommendations can be made.

Survival of In-Hospital Cardiopulmonary Arrest in Trauma Patients

INTRODUCTION

Relative to other hospitalized patients, trauma patients are younger with fewer comorbidities, but the incidence and outcomes of in-hospital cardiopulmonary arrest (IHCA) with cardiopulmonary resuscitation (CPR) in this population is unknown. Therefore, we aimed to investigate factors associated with survival in trauma patients after IHCA to test the hypothesis that compared to other hospitalized patients, trauma patients with IHCA have improved survival.

METHODS

Retrospective review of the Trauma Quality Improvement Program database 2017 to 2019 for patients who had IHCA with CPR. Primary outcome was survival to hospital discharge. Secondary outcomes were in-hospital complications, hospital length of stay, intensive care unit length of stay, and ventilator days. Data were compared with univariate and multivariate analyses at P < 0.05.

RESULTS

In 22,346,677 admitted trauma patients, 14,056 (0.6%) received CPR. Four thousand three hundred seventy-seven (31.1%) survived to discharge versus 26.4% in a national sample of all hospitalized patients (P < 0.001). In trauma patients, median age was 55 y, the majority were male (72.2%). Mortality was higher for females versus males (70.3% versus 68.3%, P = 0.026). Multivariate regression showed that older age 1.01 (95% confidence interval (CI) 1.01-1.02), Hispanic ethnicity 1.21 (95% CI 1.04-1.40), and penetrating trauma 1.51 (95% CI 1.32-1.72) were risk factors for mortality, while White race was a protective factor 0.36 (95% CI 0.14-0.89).

CONCLUSIONS

This is the first study to show that the incidence of IHCA with CPR is approximately six in 1000 trauma admissions and 31% survive to hospital discharge, which is higher than other hospitalized patients. Age, gender, racial, and ethnic disparities also influence survival.

Pro-Con Debate: Universal Versus Selective Continuous Monitoring of Postoperative Patients

In this Pro-Con commentary article, we discuss use of continuous physiologic monitoring for clinical deterioration, specifically respiratory depression in the postoperative population. The Pro position advocates for 24/7 continuous surveillance monitoring of all patients starting in the postanesthesia care unit until discharge from the hospital. The strongest arguments for universal monitoring relate to inadequate assessment and algorithms for patient risk. We argue that the need for hospitalization in and of itself is a sufficient predictor of an individual's risk for unexpected respiratory deterioration. In addition, general care units carry the added risk that even the most severe respiratory events will not be recognized in a timely fashion, largely due to higher patient to nurse staffing ratios and limited intermittent vital signs assessments (e.g., every 4 hours). Continuous monitoring configured properly using a "surveillance model" can adequately detect patients' respiratory deterioration while minimizing alarm fatigue and the costs of the surveillance systems. The Con position advocates for a mixed approach of time-limited continuous pulse oximetry monitoring for all patients receiving opioids, with additional remote pulse oximetry monitoring for patients identified as having a high risk of respiratory depression. Alarm fatigue, clinical resource limitations, and cost are the strongest arguments for selective monitoring, which is a more targeted approach. The proponents of the con position acknowledge that postoperative respiratory monitoring is certainly indicated for all patients, but not all patients need the same level of monitoring. The analysis and discussion of each point of view describes who, when, where, and how continuous monitoring should be implemented. Consideration of various system-level factors are addressed, including clinical resource availability, alarm design, system costs, patient and staff acceptance, risk-assessment algorithms, and respiratory event detection. Literature is reviewed, findings are described, and recommendations for design of monitoring systems and implementation of monitoring are described for the pro and con positions.

Frailty: the perioperative and anesthesia challenges of an emerging pandemic

Frailty is a complex and multisystem biological process characterized by reductions in physiological reserve. It is an increasingly common phenomena in the surgical population, and significantly impacts postoperative recovery. In this review, we will discuss the pathophysiology of frailty, as well as preoperative, intraoperative, and postoperative considerations for frailty care. We will also discuss the different models of postoperative care, including enhanced recovery pathways, as well as elective critical care admission. With discoveries of new effective interventions, and advances in healthcare information technology, optimized pathways could be developed to provide the best care possible that meets the challenges of perioperative frailty.

Society of Anesthesia and Sleep Medicine Position Paper on Patient Sleep During Hospitalization

This article addresses the issue of patient sleep during hospitalization, which the Society of Anesthesia and Sleep Medicine believes merits wider consideration by health authorities than it has received to date. Adequate sleep is fundamental to health and well-being, and insufficiencies in its duration, quality, or timing have adverse effects that are acutely evident. These include cardiovascular dysfunction, impaired ventilatory function, cognitive impairment, increased pain perception, psychomotor disturbance (including increased fall risk), psychological disturbance (including anxiety and depression), metabolic dysfunction (including increased insulin resistance and catabolic propensity), and immune dysfunction and proinflammatory effects (increasing infection risk and pain generation). All these changes negatively impact health status and are counterproductive to recovery from illness and operation. Hospitalization challenges sleep in a variety of ways. These challenges include environmental factors such as noise, bright light, and overnight awakenings for observations, interventions, and transfers; physiological factors such as pain, dyspnea, bowel or urinary dysfunction, or discomfort from therapeutic devices; psychological factors such as stress and anxiety; care-related factors including medications or medication withdrawal; and preexisting sleep disorders that may not be recognized or adequately managed. Many of these challenges appear readily addressable. The key to doing so is to give sleep greater priority, with attention directed at ensuring that patients' sleep needs are recognized and met, both within the hospital and beyond. Requirements include staff education, creation of protocols to enhance the prospect of sleep needs being addressed, and improvement in hospital design to mitigate environmental disturbances. Hospitals and health care providers have a duty to provide, to the greatest extent possible, appropriate preconditions for healing. Accumulating evidence suggests that these preconditions include adequate patient sleep duration and quality. The Society of Anesthesia and Sleep Medicine calls for systematic changes in the approach of hospital leadership and staff to this issue. Measures required include incorporation of optimization of patient sleep into the objectives of perioperative and general patient care guidelines. These steps should be complemented by further research into the impact of hospitalization on sleep, the effects of poor sleep on health outcomes after hospitalization, and assessment of interventions to improve it.

Opioid and Sedative Coprescription: Prescribing Patterns after an ICU Admission

Background

Opioid misuse constitutes a health care crisis in Canada, and coprescription of opioids with sedatives has been associated with adverse events. Opioids and sedatives are frequently administered in the intensive care unit (ICU). The rate of continuation of opioid-sedative combinations after an ICU admission at the study institution was unknown.

Objectives

To determine the rates of opioid and sedative coprescriptions following an ICU admission and to identify factors associated with continuation of hospital-initiated opioid-sedative coprescriptions at ICU transfer and hospital discharge.

Methods

This retrospective chart review involved patients admitted to ICUs at a tertiary care centre between April 1, 2018, and March 31, 2019. Baseline characteristics were obtained from a clinical database and medication information from medication reconciliation forms. An opioid coprescription was defined as prescription of an opioid in combination with a sedative (benzodiazepine, z-drug, gabapentinoid, tricyclic antidepressant, or antipsychotic), and hospital-initiated coprescriptions encompassed various predefined scenarios of therapy started or modified before ICU transfer. Factors associated with hospital-initiated opioid coprescription were analyzed by multivariable logistic regression.

Results

A total of 735 patients met the inclusion criteria. At ICU transfer, 23.0% (169/735) of the patients had an opioid coprescription, and 87.0% (147/169) of these coprescriptions were hospital-initiated. At hospital discharge, 8.6% (44/514) of the patients had an opioid coprescription, and 56.8% (25/44) of these coprescriptions were hospital-initiated. Male sex, home opioid coprescription, surgical patient, prolonged hospital stay, and in-hospital death were significantly associated with hospital-initiated opioid coprescription at the time of ICU transfer. Home opioid coprescription was significantly associated with opioid coprescription at the time of hospital discharge.

Conclusions

Hospital-initiated opioid coprescriptions accounted for the majority of opioid coprescriptions at ICU transfer and hospital discharge. Pharmacists should assess all opioid coprescriptions to determine whether discontinuation and/or dose reduction is appropriate.

Incorporating economic analysis in interventional cardiology research

Evaluative research in interventional cardiology has focused on clinical and technical outcomes. Inclusion of economic data can enhance evaluative research by quantifying the relative economic burden incurred by different therapies. When combined with clinical outcomes, cost data can provide a measure of value (e.g., marginal cost-effectiveness). In some select situations, cost data can also be used as surrogates for complexity of care and morbidity. In this narrative review, we aim to provide a framework for the application of cost data in clinical trials and observational research, detailing how to incorporate this kind of data into interventional cardiology research.

Respiratory monitoring of nonintubated patients in nonoperating room settings: old and new technologies

PURPOSE OF REVIEW

Postoperative mortality in the 30 days after surgery remains disturbingly high. Inadequate, intermittent and incomplete monitoring of vital signs in the nonoperating room environment is common practice. The rise of nonoperating room anaesthesia and sedation outside the operating room has highlighted the need to develop new and robust methods of portable continuous respiratory monitoring. This review provides a summary of old and new technologies in this environment.

RECENT FINDINGS

Technical advances have made possible the utilization of established monitoring to extrapolate respiratory rate, the increased availability and user friendliness of side stream capnography and the advent of other innovative systems. The use of aggregate signals wherein different modalities compensate for individual shortcomings seem to provide a reliable and artefact-free system.

SUMMARY

Respiratory monitoring is required in several situations and patient categories outside the operating room. The chosen modality must be able to detect respiratory compromise in a timely and accurate manner. Combing several modalities in a nonobtrusive, nontethered system and having an integrated output seems to give a reliable and responsive signal.

Predicting opioid-induced oversedation in hospitalised patients: a multicentre observational study

OBJECTIVES

Opioid-induced respiratory depression (OIRD) and oversedation are rare but potentially devastating adverse events in hospitalised patients. We investigated which features predict an individual patient's risk of OIRD or oversedation; and developed a risk stratification tool that can be used to aid point-of-care clinical decision-making.

DESIGN

Retrospective observational study.

SETTING

Twelve acute care hospitals in a large not-for-profit integrated delivery system.

PARTICIPANTS

All inpatients ≥18 years admitted between 1 July 2016 and 30 June 2018 who received an opioid during their stay (163 190 unique hospitalisations).

MAIN OUTCOME MEASURES

The primary outcome was occurrence of sedation or respiratory depression severe enough that emergent reversal with naloxone was required, as determined from medical record review; if naloxone reversal was unsuccessful or if there was no evidence of hypoxic encephalopathy or death due to oversedation, it was not considered an oversedation event.

RESULTS

Age, sex, body mass index, chronic obstructive pulmonary disease, concurrent sedating medication, renal insufficiency, liver insufficiency, opioid naïvety, sleep apnoea and surgery were significantly associated with risk of oversedation. The strongest predictor was concurrent administration of another sedating medication (adjusted HR, 95% CI=3.88, 2.48 to 6.06); the most common such medications were benzodiazepines (29%), antidepressants (22%) and gamma-aminobutyric acid analogue (14.7%). The c-statistic for the final model was 0.755. The 24-point Oversedation Risk Criteria (ORC) score developed from the model stratifies patients as high (>20%, ≥21 points), moderate (11%-20%, 10-20 points) and low risk (≤10%, <10 points).

CONCLUSIONS

The ORC risk score identifies patients at high risk for OIRD or oversedation from routinely collected data, enabling targeted monitoring for early detection and intervention. It can also be applied to preventive strategies-for example, clinical decision support offered when concurrent prescriptions for opioids and other sedating medications are entered that shows how the chosen combination impacts the patient's risk.

Evaluating oliceridine as a treatment option for moderate to severe acute post-operative pain in adults

INTRODUCTION

Despite the advances in regional anesthesia and non-opioid systemic analgesia, opioids remain the primary rescue analgesic for moderate to severe pain. However, the risks and side effects of opioid medications are well documented. Oliceridine is a novel opioid receptor agonist which is thought to have less risk of adverse events, such as postoperative nausea and vomiting (PONV) and respiratory depression.

AREAS COVERED

In this review, the authors discuss the limitations of the current opioid and non-opioid analgesic options. They also review the pharmacokinetics of oliceridine, its analgesic efficacy, and risk of adverse events; and its added clinical value in managing moderate to severe pain.

EXPERT OPINION

Despite the advances in regional anesthesia and multimodal systemic analgesia, opioid free analgesia is only feasible in selected procedures and patients. Oliceridine is effective in the management of moderate to severe pain and appears to be associated with lower risk of nausea and vomiting. The risk of sedation and respiratory depression associated with oliceridine will require further study. The availability of an opioid agonist with a better side effect profile could potentially change the current paradigm of opioid avoidance in postoperative pain management.

Multi-Level Regulation of Opioid-Induced Respiratory Depression

Opioids depress minute ventilation primarily by reducing respiratory rate. This results from direct effects on the preBötzinger Complex as well as from depression of the Parabrachial/Kölliker-Fuse Complex, which provides excitatory drive to preBötzinger Complex neurons mediating respiratory phase-switch. Opioids also depress awake drive from the forebrain and chemodrive.

Modeling the Cost Savings of Continuous Pulse Oximetry and Capnography Monitoring of United States General Care Floor Patients Receiving Opioids Based on the PRODIGY Trial

INTRODUCTION

Despite the high incidence of respiratory depression on the general care floor and evidence that continuous monitoring improves patient outcomes, the cost-benefit of continuous pulse oximetry and capnography monitoring of general care floor patients remains unknown. This study modeled the cost and length of stay savings, investment break-even point, and likelihood of cost savings for continuous pulse oximetry and capnography monitoring of general care floor patients at risk for respiratory depression.

METHODS

A decision tree model was created to compare intermittent pulse oximetry versus continuous pulse oximetry and capnography monitoring. The model utilized costs and outcomes from the PRediction of Opioid-induced respiratory Depression In patients monitored by capnoGraphY (PRODIGY) trial, and was applied to a modeled cohort of 2447 patients receiving opioids per median-sized United States general care floor annually.

RESULTS

Continuous pulse oximetry and capnography monitoring of high-risk patients is projected to reduce annual hospital cost by $535,531 and cumulative patient length of stay by 103 days. A 1.5% reduction in respiratory depression would achieve a break-even investment point and justify the investment cost. The probability of cost saving is ≥ 80% if respiratory depression is decreased by ≥ 17%. Expansion of continuous monitoring to high- and intermediate-risk patients, or to all patients, is projected to reach a break-even point when respiratory depression is reduced by 2.5% and 3.5%, respectively, with a ≥ 80% probability of cost savings when respiratory depression decreases by ≥ 27% and ≥ 31%, respectively.

CONCLUSION

Compared to intermittent pulse oximetry, continuous pulse oximetry and capnography monitoring of general care floor patients receiving opioids has a high chance of being cost-effective.

TRIAL REGISTRATION

www.clinicaltrials.gov , Registration ID: NCT02811302.

Pharmacologically Induced Ventilatory Depression in the Postoperative Patient: A Sleep-Wake State-Dependent Perspective

Pharmacologically induced ventilatory depression (PIVD) is a common postoperative complication with a spectrum of severity ranging from mild hypoventilation to severe ventilatory depression, potentially leading to anoxic brain injury and death. Recent studies, using continuous monitoring technologies, have revealed alarming rates of previously undetected severe episodes of postoperative ventilatory depression, rendering the recognition of such episodes by the standard intermittent assessment practice, quite problematic. This imprecise description of the epidemiologic landscape of PIVD has thus stymied efforts to understand better its pathophysiology and quantify relevant risk factors for this postoperative complication. The residual effects of various perianesthetic agents on ventilatory control, as well as the multiple interactions of these drugs with patient-related factors and phenotypes, make postoperative recovery of ventilation after surgery and anesthesia a highly complex physiological event. The sleep-wake, state-dependent variation in the control of ventilation seems to play a central role in the mechanisms potentially enhancing the risk for PIVD. Herein, we discuss emerging evidence regarding the epidemiology, risk factors, and potential mechanisms of PIVD.

Opioid Overdose in the Hospital Setting: A Systematic Review

OBJECTIVE

Our objective was to determine the percentage of opioid overdose events among medical and surgical inpatient admissions, and to identify risk factors associated with these events.

METHODS

We searched PubMed and CINAHL databases from inception through July 30, 2017 and identified additional studies from reference lists and other reviews. Articles were included if they reported original research on the rate of opioid overdoses or opioid-related adverse events, and the adverse events occurred in a general medical hospital during an inpatient stay. We extracted information on study population, design, results, and risk for bias using the Newcastle-Ottawa Quality Assessment Scale. We performed this review in accordance with recently suggested standards and report our findings as per the Meta-Analyses and Systematic Reviews of Observational Studies guidelines.

RESULTS

Thirteen studies met our eligibility criteria. The percentage of opioid overdoses ranged from 0.06% to 2.50% of hospitalizations. The majority of studies used only 1 method of event detection. Risk factors for overdose included older age, infancy, medical comorbidity, substance use disorder diagnosis, combining opioids with other sedatives, and admission to hospitals with higher opioid-prescribing rates.

CONCLUSIONS

Opioid overdose in the inpatient setting is a serious preventable harm and is likely underestimated in much of the current literature. Improved detection methods are needed to more accurately measure the rate of inpatient opioid overdose. Refined estimates of opioid overdose should be used to drive safety and quality improvement initiatives in hospitals.

Safety of treatment options available for postoperative pain

IntroductionPostoperative pain is one of the most common adverse events after surgery and has been shown to increase the risk of other complications. On the other hand, liberal opioid use in the perioperative period is also associated with risk of adverse events. The current consensus is therefore to provide multimodal, opioid minimizing analgesia after surgery.Areas CoveredIn this review, we will discuss the benefits and risks associated with non-opioid analgesics, including non-steroidal anti-inflammatory drugs, gabapentinoids, ketamine, α-2 agonists, and corticosteroids. In addition, we will discuss the general and block-specific risks associated with regional anesthestic techniques.Expert OpinionAdverse events associated with non-opioid analgesics are rare outside their specific contraindicated patient groups, especially when dosed appropriately. α-2 agonists can cause transient hypotension and bradycardia, and gabapentinoids may cause sedation in higher risk patient populations. Regional anesthesia techniques are generally safe when done by an experienced practitioner. We therefore encourage the development of standardized multimodal analgesic protocols, which may facilitate opioid minimization and lead to better patient outcomes.

The problem of postoperative respiratory depression

WHAT IS KNOWN AND OBJECTIVE

Postsurgical recovery is influenced by multiple pre-, intra- and perioperative pharmacotherapeutic interventions, including the administration of medications that can induce respiratory depression postoperatively. We present a succinct overview of the topic, including the nature and magnitude of the problem, contributing factors, current limited options, and potential novel therapeutic approach.

COMMENT

Pre-, intra- and perioperative medications are commonly administered for anxiety, anaesthesia, muscle relaxation and pain relief among other reasons. Several of the medications alone or in joint-action can be additive or synergistic producing respiratory depression. Given the large number of surgical procedures that are performed each year, even a small percentage of postoperative respiratory complications translates into a large number of affected patients.

WHAT IS NEW AND CONCLUSION

Due to the large number of surgeries performed each year, and the variety of medications used before, during, and after surgery, the occurrence of postoperative respiratory depression is surprisingly common. It is a significant medical problem and burden on hospital resources. There is a need for new strategies to prevent and treat the acute and collateral problems associated with postoperative respiratory depression.

Pupillary unrest, opioid intensity, and the impact of environmental stimulation on respiratory depression

Opioid-induced respiratory depression (OIRD) confers significant morbidity, but its onset can be challenging to recognize. Pain or stimulation effects of conversation may mask or attenuate common clinical manifestations of OIRD. We asked whether pupillary unrest could provide an objective signal of opioid exposure, and whether this signal would be independent from the confounding influence of extrinsic stimulation. We conducted a cross-over trial of healthy volunteers using identical remifentanil infusions separated by a washout period; in both, pupillary unrest in ambient light (PUAL) was measured at 2.5-min intervals. During one infusion, investigators continuously engaged the subject in conversation, while in the other, a quiet environment was maintained; measures of respiratory depression were compared under each condition. We tested PUAL’s relationship to estimated opioid concentration under quiet conditions, measured PUAL’s discrimination of lower versus higher opioid exposure using receiver operating characteristic (ROC) analysis, and assessed the effect of stimulation on PUAL versus opioid using mixed effects regression. Respiratory depression occurred more frequently under quiet conditions (p < 0.0001). Under both conditions, PUAL declined significantly over the course of the remifentanil infusion and rose during recovery (p < 0.0001). PUAL showed excellent discrimination in distinguishing higher versus absent-moderate opioid exposure (AUROC = 0.957 [0.929 to 0.985]), but was unaffected by interactive versus quiet conditions (mean difference, interactive – quiet = − 0.007, 95% CI − 0.016 to 0.002). PUAL is a consistent indicator of opioid effect, and distinguishes higher opioid concentrations independently of the stimulating effects of conversational interaction. Under equivalent opioid exposure, conversational interaction delayed the onset and minimized the severity of OIRD.

Clinical trial registration: NCT 04301895

Postoperative opioid administration characteristics associated with opioid-induced respiratory depression: Results from the PRODIGY trial

STUDY OBJECTIVE

Opioid administration for pain in general care floor patients remains common, and can lead to adverse outcomes, including respiratory compromise. The PRODIGY trial found that among ward patients receiving parenteral opioids, 46% experienced ≥1 respiratory depression episode. The objective of this analysis was to evaluate the geographic differences of opioid administration and examine the association between opioid administration characteristics and the occurrence of respiratory depression.

DESIGN

Prospective observational trial.

SETTING

16 general care medical and surgical wards in Asia, Europe, and the United States.

PATIENTS

1335 patients receiving parenteral opioids.

INTERVENTIONS

Blinded, alarm-silenced continuous capnography and pulse oximetry monitoring.

MEASUREMENTS

Opioid-induced respiratory depression, defined as respiratory rate ≤ 5 bpm, SpO₂ ≤ 85%, or ETCO₂ ≤ 15 or ≥ 60 mmHg for ≥3 min; apnea episode lasting >30 s; or any respiratory opioid-related adverse event.

RESULTS

Across all patients, 58% received only long-acting opioids, 16% received only short-acting (<3 h) opioids, and 21% received a combination of short- and long-acting (≥3 h) opioids. The type and median total morphine milligram equivalent (MME) of opioid administered varied significantly by region, with 31.5 (12.5-76.7) MME, 31.0 (6.2-99.0) MME, and 7.2 (1.7-18.7) MME in the United States, Europe, and Asia, respectively (p < 0.001). Considering only postoperative opioids, 54% (N = 119/220) and 45% (N = 347/779) of patients receiving only short-acting opioids or only long-acting opioids experienced ≥1 episode of opioid-induced respiratory depression, respectively. Multivariable analysis identified post-procedure tramadol (OR 0.62, 95% CI 0.424-0.905, p = 0.0133) and post-procedure epidural opioids (OR 0.485, 95% CI 0.322-0.731, p = 0.0005) being associated with a significant reduction in opioid-induced respiratory depression.

CONCLUSIONS

Despite varying opioid administration characteristics between Asia, Europe, and the United States, opioid-induced respiratory depression remains a common global problem on general care medical and surgical wards. While the use of post-procedure tramadol or post-procedure epidural opioids may reduce the incidence of respiratory depression, continuous monitoring is also necessary to ensure patient safety when receiving postoperative opioids. REGISTRATION NUMBER: www.clinicaltrials.gov, ID: NCT02811302.

A Prospective Observational Study of Emergency Department-Initiated Physical Therapy for Acute Low Back Pain

OBJECTIVE

Low back pain accounts for nearly 4 million emergency department (ED) visits annually and is a significant source of disability. Physical therapy has been suggested as a potentially effective nonopioid treatment for low back pain; however, no studies to our knowledge have yet evaluated the emerging resource of ED-initiated physical therapy. The study objective was to compare patient-reported outcomes in patients receiving ED-initiated physical therapy and patients receiving usual care for acute low back pain.

METHODS

This was a prospective observational study of ED patients receiving either physical therapy or usual care for acute low back pain from May 1, 2018, to May 24, 2019, at a single academic ED (>91,000 annual visits). The primary outcome was pain-related functioning, assessed with Oswestry Disability Index (ODI) and Patient-Reported Outcomes Measurement Information System pain interference (PROMIS-PI) scores. The secondary outcome was use of high-risk medications (opioids, benzodiazepines, and skeletal muscle relaxants). Outcomes were compared over 3 months using adjusted linear mixed and generalized estimating equation models.

RESULTS

For 101 participants (43 receiving ED-initiated physical therapy and 58 receiving usual care), the median age was 40.5 years and 59% were women. Baseline outcome scores in the ED-initiated physical therapy group were higher than those in the usual care group (ODI = 51.1 vs 36.0; PROMIS-PI = 67.6 vs 62.7). Patients receiving ED-initiated physical therapy had greater improvements in both ODI and PROMIS-PI scores at the 3-month follow-up (ODI = -14.4 [95% CI = -23.0 to -5.7]; PROMIS-PI = -5.1 [95% CI = -9.9 to -0.4]) and lower use of high-risk medications (odds ratio = 0.05 [95% CI = 0.01 to 0.58]).

CONCLUSION

In this single-center observational study, ED-initiated physical therapy for acute low back pain was associated with improvements in functioning and lower use of high-risk medications compared with usual care; the causality of these relationships remains to be explored.

IMPACT

ED-initiated physical therapy is a promising therapy for acute low back pain that may reduce reliance on high-risk medications while improving patient-reported outcomes.

LAY SUMMARY

Emergency department-initiated physical therapy for low back pain was associated with greater improvement in functioning and lower use of high-risk medications over 3 months.

Polypharmacy prior to in-hospital cardiac arrest among patients with cardiopulmonary diseases: A pilot study

Background

Patterns of medication administration prior to in-hospital cardiac arrest (I-HCA) and the potential impact of these on patient outcomes is not well-established. Accordingly, types of medications administered in the 72 h prior to I-HCA were examined in relation to initial rhythms of I-HCA and survival.

Methods

A retrospective, pilot study was conducted among 96 patients who experienced I-HCA. Clinical characteristics and treatments including medications were extracted from electronic health records. Relative risk (RR) of medications or class of medications associated with the initial rhythms of I-HCA and return of spontaneous circulation (ROSC) were calculated.

Results

Two distinct sub-groups were identified that did not survive to hospital discharge (n = 31): 1) those who received either vasopressin/desmopressin (n = 16) and 2) those who received combinations of psychotherapeutic agents with anxiolytics, sedatives, and hypnotics (n = 15) prior to I-HCA. The risk of pulseless electrical activity and asystolic arrest was high in patients who received sympathomimetic agents alone or in combination with β-Adrenergic blocking agents, (RR = 1.40, 1.41, respectively). Vasopressin and a combination of vasopressin and fentanyl were associated with risk of unsuccessful ROSC (RR = 2.50, 2.38, respectively).

Conclusions

The types of medications administered during inpatient care may serve as a surrogate marker for identifying patients at risk of specific initial rhythms of I-HCA and survival.

Prediction of Opioid-Induced Respiratory Depression on Inpatient Wards Using Continuous Capnography and Oximetry: An International Prospective, Observational Trial

BACKGROUND

Opioid-related adverse events are a serious problem in hospitalized patients. Little is known about patients who are likely to experience opioid-induced respiratory depression events on the general care floor and may benefit from improved monitoring and early intervention. The trial objective was to derive and validate a risk prediction tool for respiratory depression in patients receiving opioids, as detected by continuous pulse oximetry and capnography monitoring.

METHODS

PRediction of Opioid-induced respiratory Depression In patients monitored by capnoGraphY (PRODIGY) was a prospective, observational trial of blinded continuous capnography and oximetry conducted at 16 sites in the United States, Europe, and Asia. Vital signs were intermittently monitored per standard of care. A total of 1335 patients receiving parenteral opioids and continuously monitored on the general care floor were included in the analysis. A respiratory depression episode was defined as respiratory rate ≤5 breaths/min (bpm), oxygen saturation ≤85%, or end-tidal carbon dioxide ≤15 or ≥60 mm Hg for ≥3 minutes; apnea episode lasting >30 seconds; or any respiratory opioid-related adverse event. A risk prediction tool was derived using a multivariable logistic regression model of 46 a priori defined risk factors with stepwise selection and was internally validated by bootstrapping.

RESULTS

One or more respiratory depression episodes were detected in 614 (46%) of 1335 general care floor patients (43% male; mean age, 58 ± 14 years) continuously monitored for a median of 24 hours (interquartile range [IQR], 17-26). A multivariable respiratory depression prediction model with area under the curve of 0.740 was developed using 5 independent variables: age ≥60 (in decades), sex, opioid naivety, sleep disorders, and chronic heart failure. The PRODIGY risk prediction tool showed significant separation between patients with and without respiratory depression (P < .001) and an odds ratio of 6.07 (95% confidence interval [CI], 4.44-8.30; P < .001) between the high- and low-risk groups. Compared to patients without respiratory depression episodes, mean hospital length of stay was 3 days longer in patients with ≥1 respiratory depression episode (10.5 ± 10.8 vs 7.7 ± 7.8 days; P < .0001) identified using continuous oximetry and capnography monitoring.

CONCLUSIONS

A PRODIGY risk prediction model, derived from continuous oximetry and capnography, accurately predicts respiratory depression episodes in patients receiving opioids on the general care floor. Implementation of the PRODIGY score to determine the need for continuous monitoring may be a first step to reduce the incidence and consequences of respiratory compromise in patients receiving opioids on the general care floor.

Continuous peripheral nerve blocks compared to thoracic epidurals or multimodal analgesia for midline laparotomy: a systematic review and meta-analysis

BACKGROUND

Continuous peripheral nerve blocks (CPNBs) have been investigated to control pain for abdominal surgery via midline laparotomy while avoiding the adverse events of opioid or epidural analgesia. The review compiles the evidence comparing CPNBs to multimodal and epidural analgesia.

METHODS

We conducted a systematic review using broad search terms in MEDLINE, EMBASE, Cochrane. Primary outcomes were pain scores and cumulative opioid consumption at 48 hours. Secondary outcomes were length of stay and postoperative nausea and vomiting (PONV). We rated the quality of the evidence using Cochrane and GRADE recommendations. The results were synthesized by meta-analysis using Revman.

RESULTS

Our final selection included 26 studies (1,646 patients). There was no statistically significant difference in pain control comparing CPNBs to either multimodal or epidural analgesia (low quality evidence). Less opioids were consumed when receiving epidural analgesia than CPNBs (mean difference [MD]: -16.13, 95% CI [-32.36, 0.10]), low quality evidence) and less when receiving CPNBs than multimodal analgesia (MD: -31.52, 95% CI [-42.81, -20.22], low quality evidence). The length of hospital stay was shorter when receiving epidural analgesia than CPNBs (MD: -0.78 days, 95% CI [-1.29, -0.27], low quality evidence) and shorter when receiving CPNBs than multimodal analgesia (MD: -1.41 days, 95% CI [-2.45, -0.36], low quality evidence). There was no statistically significant difference in PONV comparing CPNBs to multimodal (high quality evidence) or epidural analgesia (moderate quality evidence).

CONCLUSIONS

CPNBs should be considered a viable alternative to epidural analgesia when contraindications to epidural placement exist for patients undergoing midline laparotomies.

A methodology to explore ventilatory chemosensitivity and opioid-induced respiratory depression risk

Our new and noteworthy methodology allows for exploration of preoperative ventilatory chemosensitivity, measured as the hypercapnic ventilatory response (HCVR), as a risk factor for postoperative opioid-induced respiratory depression (OIRD). This feasible and reliable methodology produced preliminary data that showed highly variable depression of HCVR by remifentanil, predominance of OIRD during light sleep, and potentially negative correlation between OIRD frequency generally and HCVR measurements when measured in the presence of remifentanil. Although the results are preliminary in nature, this novel methodology may guide future studies that can one day lead to effective clinical screening tools.

Postoperative opioid-free analgesia in elective bowel resection: Changes over time

In the pain management evolution, opioid-free analgesia and multimodal analgesia strategies have emerged as feasible in many surgical settings including colorectal surgery. This was a retrospective cohort study including patients having undergone elective bowel resection between February 2012 and June 2018 aiming to evaluate whether there was reduction in opioid use after implementation of opioid-free analgesia in one medical centre. Trend analysis was conducted using Joinpoint regression employing nine-month intervals. The primary outcome for each interval was the proportion of patients receiving postoperative opioid-free analgesia, defined as forgoing all opioid analgesics after the day of surgery. This study showed a significant increasing trend in opioid-free analgesia in elective bowel resection from 0 to 42.5% over 4.5 years.

Respiratory events associated with concomitant opioid and sedative use among Medicare beneficiaries with chronic obstructive pulmonary disease

BACKGROUND

Opioids and sedatives are commonly prescribed in chronic obstructive pulmonary disease (COPD) patients for symptoms of dyspnoea, pain, insomnia, depression and anxiety. Older adults are advised to avoid these medications due to increased adverse events, including respiratory events. This study examines respiratory event risks associated with concomitant opioid and sedative use compared with opioid use alone in older adults with COPD.

METHODS

A 5% nationally representative sample of Medicare beneficiaries with COPD and opioid use between 2009 and 2013 was used for this retrospective cohort study. Current and past concomitant use were identified using drug dispensed within 7 days from the censored date: at respiratory event, at death, or at 12 months post index. Concomitant opioid and sedative use were categorised into no overlap (opioid only), 1 to 10, 11 to 30, 31 to 60 and >60 days of total overlap. The primary outcome was hospitalisation or emergency department (ED) visits for respiratory events (COPD exacerbations or respiratory depression). Propensity score matching was implemented and semi-competing risk models were used to address competing risk by death.

RESULTS

Among 48 120 eligible beneficiaries, 1810 (16.7%) concomitant users were matched with 9050 (83.3%) opioid only users. Current concomitant use of 1 to 10, 11 to 30 and 31 to 60 days was associated with increased respiratory events (HRs (95% CI): 2.8 (1.2 to 7.3), 9.3 (4.9 to 18.2) and 5.7 (2.5 to 12.5), respectively), compared with opioid only use. Current concomitant use of >60 days or past concomitant use of ≤60 days was not significantly associated with respiratory events. Consistent findings were found in sensitivity analyses, including in subgroup analysis of non-benzodiazepine sedatives. Additionally, current concomitant use significantly increased risk of death.

CONCLUSION

Short-term and medium-term current concomitant opioid and sedative use significantly increased risk of respiratory events and death in older COPD Medicare beneficiaries. Long-term past concomitant users, however, demonstrated lower risks of these outcomes, possibly reflecting a healthy user effect or developed tolerance to the effects of these agents.

Risk Factors for Severe Opioid-Related Adverse Events in a National Cohort of Medical Hospitalizations

BACKGROUND

Opioids are a leading cause of adverse drug events in the hospital. Guidelines recommend that physicians assess the risks of opioids and discuss them with patients when considering opioid use. There are no studies examining patient- and prescribing-related risk factors for opioid-related adverse drug events (ORADEs) in hospitalized medical patients.

OBJECTIVE

To identify independent risk factors for severe ORADEs in hospitalized medical patients.

DESIGN

Retrospective cohort study.

PATIENTS

Medical patients hospitalized at US, non-federal, and acute care facilities, with at least one pharmacy charge for an opioid during hospitalization. We excluded patients with metastatic malignancy, hospice, or palliative care billing codes.

MAIN MEASURES

We used Cox proportional hazards modeling to identify risk factors for severe ORADEs, defined by a pharmacy charge for naloxone. Candidate risk factors were chosen a priori, based on clinical grounds and prior literature.

KEY RESULTS

Among 731,208 hospitalizations (median age 60, 56.5% female), a severe ORADE occurred in 2727 (0.4%). Independent risk factors included patient characteristics (advanced age, female gender), comorbidities (congestive heart failure, opioid abuse/dependence, non-opioid drug abuse/dependence, psychosis, depression, obstructive sleep apnea), organ failures on admission (respiratory failure, shock/hypotension, renal failure, hepatic failure, acidosis, and neurologic failure), medication co-administrations (antipsychotics and short-acting benzodiazepines), and characteristics of the opioid prescriptions themselves (total dose for the day, parenteral route of administration, and receipt of multiple types of opioids in a day). Although a risk prediction model derived from these factors performed well on stratified k-fold cross-validation (average c-statistics 0.68-0.71), the low incidence of the outcome limited the positive predictive value of the risk score.

CONCLUSIONS

In this national cohort of medical patients, we identified several risk factors for ORADEs that can be used to inform physician decision-making, conversations with patients about risk, and development and targeting of harm reduction strategies for at-risk populations.

Prediction of Drug-Drug Interactions Between Opioids and Overdosed Benzodiazepines Using Physiologically Based Pharmacokinetic (PBPK) Modeling and Simulation

Background

Researchers have long been interested in the potential drug–drug interactions (DDIs) between opioids and benzodiazepines. However, much remains unknown concerning the interactions between these two drug classes. The objective of this work is to study the mechanism underlying the DDIs between opioids and benzodiazepines from the perspective of their pharmacokinetic (PK) interactions. A PK interaction occurs when two drugs are metabolized by the same cytochrome P450 enzymes and is one of the most common reasons for DDIs.

Methods

We quantitatively predicted the DDIs between three opioids (fentanyl, oxycodone and buprenorphine) and four benzodiazepines (alprazolam, diazepam, midazolam and triazolam) using a physiologically based pharmacokinetic (PBPK) modeling approach. A set of PBPK models was first constructed for these common opioids and benzodiazepines using SimCYP software, and the DDIs between them were then explored at various dosages.

Results

Our simulation results suggested there were no PK interactions between normal doses of opioids and benzodiazepines; but weak interactions can be expected with the combination of opioids and overdosed benzodiazepines. Particular attention should be given to the combination of fentanyl and overdosed alprazolam since a PK interaction can be observed between them.

Conclusion

Our results appear to indicate that pharmacodynamics may play a more important role than PKs in causing DDIs between opioids and benzodiazepines. This study also demonstrated that molecular modeling can be a very useful tool to mitigate the problem of “missing metabolic reaction parameters” in PK modeling and simulation.

Electronic supplementary material

The online version of this article (10.1007/s40268-019-00282-3) contains supplementary material, which is available to authorized users.

Trend and Economic Burden of Intravenous Narcotic Analgesic Utilization in Major Vascular Interventions in the United States

BACKGROUND

The use of IV narcotic analgesics (IVNA) within the context of vascular procedures is not fully described. We sought to evaluate the burden of IVNA including narcotic analgesia-related adverse drug events (NARADE), associated mortality and hospitalization cost in open and endovascular vascular procedures, and to compare it with nonnarcotic analgesia (IVNNA).

METHODS

Retrospective cross-sectional study in hospitals participating in Premier database (2009-2015). Logistic regression analysis was implemented to report the risks of NARADE and in-hospital mortality. Negative binomial regression was used to assess length of stay and generalized linear modeling was used to estimate the hospitalization cost.

RESULTS

A total of 171,473 patients were identified. NARADE occurred in 6.2% of the cohort. NARADE group was similar in gender and race but was slightly older (median age 71 vs. 70; P < 0.001). After risk-adjustment, NARADE risk was higher in patients who received IVNA-alone in carotid and lower extremity revascularization (LER) [OR (odds ratio) (95% confidence interval [CI]): 1.17 (1.02-1.34) and 1.31 (1.14-1.50)] or combined with IVNNA [OR (95% CI): 1.34 (1.13-1.59) and 1.81 (1.54-2.13)], respectively. Patients receiving aortic repair benefited from the use of IVNA + IVNNA [OR (95% CI): 0.82 (0.69-0.98)]. Occurrence of NARADE doubled the LOS, amplified mortality risk and increased cost in all domains. NARADE increased the odds of mortality by 24.3, 6.5 (4.9-8.68) and 16.6 times and added $5,368, $12,737 and $11,349 to the cost of carotid, aortic and LER interventions, respectively. In contrast, IVNNA was not associated with NARADE risk, increased LOS or cost and showed a survival benefit in patients undergoing open aortic repair [aOR (95% CI): 0.52 (0.36-0.75)].

CONCLUSIONS AND RELEVANCE

The use of opioid-based narcotics had increased the risk of NARADE, resources utilization and NARADE-related mortality. Yet the use of nonopioid-based analgesic was safe, did not increase the cost and reduced mortality in open AA repair. This entices shifting the paradigm toward exploring nonopioid-based analgesia options in order to replace or minimize opioid requirements.

Potential opioid-related adverse events following spine surgery in elderly patients

OBJECTIVE

Understanding the clinical and economic impact of opioid-related adverse drug events (ORADEs) within spine surgery may guide both the clinician's and hospital administration's approach to treating perioperative pain, thus improving patient care and reducing hospital costs. The objective of this analysis is to understand how potential ORADEs after spine surgery in elderly patients affect length of stay, hospital revenue and their association with comorbid conditions.

PATIENTS AND METHODS

We conducted a retrospective study utilizing the Center for Medicare/Medicaid Services Administrative Database to analyze Medicare discharges between April 2016 and March 2017 involving 14 spine surgery DRGs for major spine procedures in order to identify potential ORADEs. An analysis was conducted using this database to identify the incidence of potential ORADEs as well as their impact on mean hospital length of stay and hospital revenue.

RESULTS

There were 177,432 discharges during the study period. The ORADE rate in patients undergoing spine surgery was 13.9% (24,642/177,432). The mean length of stay (LOS) for discharges with an ORADE was 3.13 days longer than without an ORADE (6.29 days with an ORADE vs 3.16 days without an ORADE). The adverse post-operative outcomes most strongly associated with potential ORADEs included shock, pneumonia, and septicemia. The mean hospital revenue per day with an ORADE was $3,076 less than without an ORADE ($7,263 with an ORADE vs $10,339 without an ORADE).

CONCLUSION

Potential ORADEs in spine surgery in elderly patients are common and are associated with longer hospitalizations and decreased hospital revenue. Perioperative pain management strategies that reduce ORADEs may improve patient care and increase hospital revenue.

Postoperative ward monitoring - Why and what now?

The postoperative ward is considered an ideal nursing environment for stable patients transitioning out of the hospital. However, approximately half of all in-hospital cardiorespiratory arrests occur here and are associated with poor outcomes. Current monitoring practices on the hospital ward mandate intermittent vital sign checks. Subtle changes in vital signs often occur at least 8-12 h before an acute event, and continuous monitoring of vital signs would allow for effective therapeutic interventions and potentially avoid an imminent cardiorespiratory arrest event. It seems tempting to apply continuous monitoring to every patient on the ward, but inherent challenges such as artifacts and alarm fatigue need to be considered. This review looks to the future where a continuous, smarter, and portable platform for monitoring of vital signs on the hospital ward will be accompanied with a central monitoring platform and machine learning-based pattern detection solutions to improve safety for hospitalized patients.

APOLLO-2: A Randomized, Placebo and Active-Controlled Phase III Study Investigating Oliceridine (TRV130), a G Protein-Biased Ligand at the μ-Opioid Receptor, for Management of Moderate to Severe Acute Pain Following Abdominoplasty

Objectives

The clinical utility of conventional IV opioids is limited by the occurrence of opioid‐related adverse events. Oliceridine is a novel G protein–biased μ‐opioid receptor agonist designed to provide analgesia with an improved safety and tolerability profile. This phase III, double‐blind, randomized trial (APOLLO‐2 [NCT02820324]) evaluated the efficacy and safety of oliceridine for acute pain following abdominoplasty.

Methods

Patients received a loading dose of either placebo, oliceridine (1.5 mg), or morphine (4 mg), followed by demand doses via patient‐controlled analgesia (0.1, 0.35, or 0.5 mg oliceridine; 1 mg morphine; or placebo) with a 6‐minute lockout interval. The primary endpoint was the proportion of treatment responders over 24 hours for oliceridine regimens compared to placebo. Secondary outcomes included a predefined composite measure of respiratory safety burden (RSB, representing the cumulative duration of respiratory safety events) and the proportion of treatment responders vs. morphine.

Results

A total of 401 patients were treated with study medication. Effective analgesia was observed for all oliceridine regimens, with responder rates of 61.0%, 76.3%, and 70.0% for the 0.1‐, 0.35‐, and 0.5‐mg regimens, respectively, compared with 45.7% for placebo (all P < 0.05) and 78.3% for morphine. Oliceridine 0.35‐ and 0.5‐mg demand dose regimens were equi‐analgesic to morphine using a noninferiority analysis. RSB showed a dose‐dependent increase across oliceridine regimens (mean hours [standard deviation], 0.1 mg: 0.43 [1.56]; 0.35 mg: 1.48 [3.83]; 0.5 mg: 1.59 [4.26]; all comparisons not significant at P > 0.05 vs. placebo: 0.60 [2.82]). The RSB measure for morphine was 1.72 (3.86) (P < 0.05 vs. placebo). Gastrointestinal adverse events increased in a dose‐dependent manner across oliceridine demand dose regimens (0.1 mg: 49.4%; 0.35 mg: 65.8%; 0.5 mg: 78.8%; vs. placebo: 47.0%; and morphine: 79.3%). In comparison to morphine, the proportion of patients experiencing nausea or vomiting was lower with the 2 equi‐analgesic dose regimens of 0.35 and 0.5 mg oliceridine.

Conclusions

Oliceridine is a safe and effective IV analgesic for the relief of moderate to severe acute postoperative pain in patients undergoing abdominoplasty. Since the low‐dose regimen of 0.1 mg oliceridine was superior to placebo but not as effective as the morphine regimen, safety comparisons to morphine are relevant only to the 2 equi‐analgesic dose groups of 0.35 and 0.5 mg, which showed a favorable safety and tolerability profile regarding respiratory and gastrointestinal adverse effects compared to morphine. These findings support that oliceridine may provide a new treatment option for patients with moderate to severe acute pain where an IV opioid is warranted.

Association of Communication Interventions to Discuss Code Status With Patient Decisions for Do-Not-Resuscitate Orders: A Systematic Review and Meta-analysis

IMPORTANCE

Whether specific communication interventions to discuss code status alter patient decisions regarding do-not-resuscitate code status and knowledge about cardiopulmonary resuscitation (CPR) remains unclear.

OBJECTIVE

To conduct a systematic review and meta-analysis regarding the association of communication interventions with patient decisions and knowledge about CPR.

DATA SOURCES

PubMed, Embase, PsycINFO, and CINAHL were systematically searched from the inception of each database to November 19, 2018.

STUDY SELECTION

Randomized clinical trials focusing on interventions to facilitate code status discussions. Two independent reviewers performed the data extraction and assessed risk of bias using the Cochrane Risk of Bias Tool. Data were pooled using a fixed-effects model, and risk ratios (RRs) with corresponding 95% CIs are reported.

DATA EXTRACTION AND SYNTHESIS

The study was performed according to the PRISMA guidelines.

MAIN OUTCOMES AND MEASURES

The primary outcome was patient preference for CPR, and the key secondary outcome was patient knowledge regarding life-sustaining treatment.

RESULTS

Fifteen randomized clinical trials (2405 patients) were included in the qualitative synthesis, 11 trials (1463 patients) were included for the quantitative synthesis of the primary end point, and 5 trials (652 patients) were included for the secondary end point. Communication interventions were significantly associated with a lower preference for CPR (390 of 727 [53.6%] vs 284 of 736 [38.6%]; RR, 0.70; 95% CI, 0.63-0.78). In a preplanned subgroup analysis, studies using resuscitation videos as decision aids compared with other interventions showed a stronger decrease in preference for life-sustaining treatment (RR, 0.56; 95% CI, 0.48-0.64 vs 1.03; 95% CI, 0.87-1.22; between-group heterogeneity P < .001). Also, a significant association was found between communication interventions and better patient knowledge (standardized mean difference, 0.55; 95% CI, 0.39-0.71).

CONCLUSIONS AND RELEVANCE

Communication interventions are associated with patient decisions regarding do-not-resuscitate code status and better patient knowledge and may thus improve code status discussions.

In-Hospital Cardiac Arrest: A Review

IMPORTANCE

In-hospital cardiac arrest is common and associated with a high mortality rate. Despite this, in-hospital cardiac arrest has received little attention compared with other high-risk cardiovascular conditions, such as stroke, myocardial infarction, and out-of-hospital cardiac arrest.

OBSERVATIONS

In-hospital cardiac arrest occurs in over 290 000 adults each year in the United States. Cohort data from the United States indicate that the mean age of patients with in-hospital cardiac arrest is 66 years, 58% are men, and the presenting rhythm is most often (81%) nonshockable (ie, asystole or pulseless electrical activity). The cause of the cardiac arrest is most often cardiac (50%-60%), followed by respiratory insufficiency (15%-40%). Efforts to prevent in-hospital cardiac arrest require both a system for identifying deteriorating patients and an appropriate interventional response (eg, rapid response teams). The key elements of treatment during cardiac arrest include chest compressions, ventilation, early defibrillation, when applicable, and immediate attention to potentially reversible causes, such as hyperkalemia or hypoxia. There is limited evidence to support more advanced treatments. Post-cardiac arrest care is focused on identification and treatment of the underlying cause, hemodynamic and respiratory support, and potentially employing neuroprotective strategies (eg, targeted temperature management). Although multiple individual factors are associated with outcomes (eg, age, initial rhythm, duration of the cardiac arrest), a multifaceted approach considering both potential for neurological recovery and ongoing multiorgan failure is warranted for prognostication and clinical decision-making in the post-cardiac arrest period. Withdrawal of care in the absence of definite prognostic signs both during and after cardiac arrest should be avoided. Hospitals are encouraged to participate in national quality-improvement initiatives.

CONCLUSIONS AND RELEVANCE

An estimated 290 000 in-hospital cardiac arrests occur each year in the United States. However, there is limited evidence to support clinical decision making. An increased awareness with regard to optimizing clinical care and new research might improve outcomes.

APOLLO-1: a randomized placebo and active-controlled phase III study investigating oliceridine (TRV130), a G protein-biased ligand at the µ-opioid receptor, for management of moderate-to-severe acute pain following bunionectomy

Purpose

Oliceridine is a novel G protein-biased µ-opioid receptor agonist designed to provide intravenous (IV) analgesia with a lower risk of opioid-related adverse events (ORAEs) than conventional opioids.

Patients and methods

APOLLO-1 (NCT02815709) was a phase III, double-blind, randomized trial in patients with moderate-to-severe pain following bunionectomy. Patients received a loading dose of either placebo, oliceridine (1.5 mg), or morphine (4 mg), followed by demand doses via patient-controlled analgesia (0.1, 0.35, or 0.5 mg oliceridine, 1 mg morphine, or placebo). The primary endpoint compared the proportion of treatment responders through 48 hours for oliceridine regimens and placebo. Secondary outcomes included a composite measure of respiratory safety burden (RSB, representing the cumulative duration of respiratory safety events) and the proportion of treatment responders vs morphine.

Results

Effective analgesia was observed for all oliceridine regimens, with responder rates of 50%, 62%, and 65.8% in the 0.1 mg, 0.35 mg, and 0.5 mg regimens, respectively (all P<0.0001 vs placebo [15.2%]; 0.35 mg and 0.5 mg non-inferior to morphine). RSB showed a dose-dependent increase across oliceridine regimens (mean hours [SD]: 0.1 mg: 0.04 [0.33]; 0.35 mg: 0.28 [1.11]; 0.5 mg: 0.8 [3.33]; placebo: 0 [0]), but none were statistically different from morphine (1.1 [3.03]). Gastrointestinal adverse events also increased in a dose-dependent manner in oliceridine regimens (0.1 mg: 40.8%; 0.35 mg: 59.5%; 0.5 mg: 70.9%; placebo: 24.1%; morphine: 72.4%). The odds ratio for rescue antiemetic use was significantly lower for oliceridine regimens compared to morphine (P<0.05).

Conclusion

Oliceridine is a novel and effective IV analgesic providing rapid analgesia for the relief of moderate-to-severe acute postoperative pain compared to placebo. Additionally, it has a favorable safety and tolerability profile with regard to respiratory and gastrointestinal adverse effects compared to morphine, and may provide a new treatment option for patients with moderate-to-severe postoperative pain where an IV opioid is required.

Risk factors for opioid-induced respiratory depression in surgical patients: a systematic review and meta-analyses

OBJECTIVE

This systematic review and meta-analysis aim to evaluate the risk factors associated with postoperative opioid-induced respiratory depression (OIRD).

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed-MEDLINE, MEDLINE in-process, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, PubMed and Clinicaltrials.gov (January 1946 to November 2017).

ELIGIBILITY CRITERIA

The inclusion criteria were: (1) adult patients 18 years or older who were administered opioids after surgery and developed postoperative OIRD (OIRD group); (2) all studies which reported both OIRD events and associated risk factors; (3) all studies with reported data for each risk factor on patients with no OIRD (control group) and (4) published articles in English language.

DATA ANALYSIS

We used a random effects inverse variance analysis to evaluate the existing evidence of risk factors associated with OIRD. Newcastle-Ottawa scale scoring system was used to assess quality of study.

RESULTS

Twelve observational studies were included from 8690 citations. The incidence of postoperative OIRD was 5.0 cases per 1000 anaesthetics administered (95% CI: 4.8 to 5.1; total patients: 841 424; OIRD: 4194). Eighty-five per cent of OIRD occurred within the first 24 hours postoperatively. Increased risk for OIRD was associated with pre-existing cardiac disease (OIRD vs control: 42.8% vs 29.6%; OR: 1.7; 95% CI: 1.2 to 2.5; I²: 0%; p<0.002), pulmonary disease (OIRD vs control: 17.8% vs 10.3%; OR: 2.2; 95% CI: 1.3 to 3.6; I²: 0%; p<0.001) and obstructive sleep apnoea (OIRD vs control: 17.9% vs 16.5%; OR: 1.4; 95% CI: 1.2 to 1.7; I²: 31%; p=0.0003). The morphine equivalent daily dose of the postoperative opioids was higher in the OIRD group than in the control; (24.7±14 mg vs 18.9±13.0 mg; mean difference: 2.8; 95% CI: 0.4 to 5.3; I²: 98%; p=0.02). There was no significant association between OIRD and age, gender, body mass index or American Society of Anesthesiologists physical status.

CONCLUSION

Patients with cardiac, respiratory disease and/or obstructive sleep apnoea were at increased risk for OIRD. Patients with postoperative OIRD received higher doses of morphine equivalent daily dose.

Acoustic respiration rate and pulse oximetry-derived respiration rate: a clinical comparison study

Respiration rate (RR) is a critical vital sign that provides early detection of respiratory compromise. The acoustic technique of measuring continuous respiration rate (RR_a) interprets the large airway sound envelope to calculate respiratory rate while pulse oximetry-derived respiratory rate (RR_oxi) interprets modulations of the photoplethsymograph in response to hemodynamic changes during the respiratory cycle. The aim of this study was to compare the performance of these technologies to each other and to a capnography-based reference device. Subjects were asked to decrease their RR from 14 to 4 breaths per minute (BPM) and then increase RR from 14 to 24 BPM. The effects of physiological noise, ambient noise, and head movement and shallow breathing on device performance were also evaluated. The test devices were: (1) RR_a, Radical-7 (Masimo Corporation), (2) RR_oxi, Nellcor™ Bedside Respiratory Patient Monitoring System (Medtronic), and (3) reference device, Capnostream20p™ (Medtronic). All devices were configured with their default settings. Twenty-nine healthy adult subjects were included in the study. During abrupt changes in breathing, overall RR_oxi was accurate for longer periods of time than RR_a; specifically, RR_oxi was more accurate during low and normal RR, but not during high RR. RR_oxi also displayed a value for significantly longer time periods than RR_a when the subjects produced physiological sounds and moved their heads, but not during shallow breathing or ambient noise. RR_oxi may be more accurate than RR_a during development of bradypnea. Also, RR_oxi may display a more reliable RR value during routine patient activities.

Practice Patterns and Treatment Challenges in Acute Postoperative Pain Management: A Survey of Practicing Physicians

INTRODUCTION

The management of acute postoperative pain remains a significant challenge for physicians. Poorly controlled postoperative pain is associated with poorer overall outcomes.

METHODS

Between April and May 2017, physicians from an online database who regularly prescribe intravenous (IV) medications for acute postoperative pain completed a 47-question survey on topics such as patient demographics, IV analgesia preferences, factors that influence prescribing decisions, and the challenges and unmet needs for the treatment of acute postoperative pain.

RESULTS

Of 501 surveyed physicians, 55% practiced in community hospitals, 60% had been in practice for > 10 years, and 60% were surgeons. The three categories of IV pain medications most likely to be prescribed to patients with moderate-to-severe pain immediately after surgery were morphine, hydromorphone, or fentanyl (95.8% of respondents); COX-2 inhibitors or nonsteroidal anti-inflammatory drugs (73.7%); and acetaminophen (60.5%). Past clinical experience (81.6%), surgery type (78.2%), and onset of analgesia (67.1%) were practice-related factors that most determined their medication choice. Key patient-related risk factors, such as avoidance of medication-related adverse events (AEs), each influenced prescription decisions in > 75.0% of physicians. Nausea and vomiting were among the most common challenges associated with postoperative pain management (76.2 and 60.3%, respectively), and avoidance of analgesic medication-related AEs was among the three most influential patient-related factors that determined prescribing decision (75%). Physicians reported the top unmet need for acute pain management in patients experiencing moderate-to-severe postoperative pain was more medications with fewer side effects (i.e., nausea, vomiting, and respiratory depression; 80.7%).

CONCLUSIONS

Opioids remain an integral component of multimodal acute analgesic therapy for acute postoperative pain in hospitalized patients. The use of all IV analgesic medications is limited by concerns over AEs, particularly with opioids and in high-risk patients. There remains a key unmet need for effective analgesic medications that are associated with a lower risk of AEs.

FUNDING

Trevena, Inc.

A Dashboard for Monitoring Opioid-Related Adverse Drug Events Following Surgery Using a National Administrative Database

Opioid-related adverse drug events (ORADEs) include a range of complications, from respiratory arrest to ileus and urinary retention. ORADEs correlate to morbidity, mortality, and increased costs. The Centers for Medicare & Medicaid Services database, which represents approximately 35% of hospital discharges. The authors searched for previously published ICD-9 codes that defined ORADEs. A group of surgical diagnosis-related groups (DRGs) were selected. Recurring queries were programmed using these ICD codes and DRGs and used to update an online dashboard. The dashboard presents an estimate of the burden of ORADEs to frontline clinicians and hospital leadership and allows users to compare local data on ORADEs rates to other hospitals. Users are able to refine their search by surgery type or ORADE type. An interface was created, using national administrative claims data, to allow hospitals to access their ORADEs and benchmark local data against national trends.

Benefit versus Severe Side Effects of Opioid Analgesia

Background

Previous studies integrated opioid benefit and harm into one single function—the utility function—to determine the drug toxicity (respiratory depression) in light of its wanted effect (analgesia). This study further refined the concept of the utility function using the respiratory and analgesic effects of the opioid analgesic alfentanil as example.

Methods

Data from three previous studies in 48 healthy volunteers were combined and reanalyzed using a population pharmacokinetic–pharmacodynamic analysis to create utility probability functions. Four specific conditions were defined: probability of adequate analgesia without severe respiratory depression, probability of adequate analgesia with severe respiratory depression, probability of inadequate analgesia without severe respiratory depression, and probability of inadequate analgesia with severe respiratory depression.

Results

The four conditions were successfully identified with probabilities varying depending on the opioid effect-site concentration. The optimum analgesia probability without serious respiratory depression is reached at an alfentanil effect-site concentration of 68 ng/ml, and exceeds the probability of the most unwanted effect, inadequate analgesia with severe respiratory depression (odds ratio, 4.0). At higher effect-site concentrations the probability of analgesia is reduced and exceeded by the probability of serious respiratory depression.

Conclusions

The utility function was successfully further developed, allowing assessment of specific conditions in terms of wanted and unwanted effects. This approach can be used to compare the toxic effects of drugs relative to their intended effect and may be a useful tool in the development of new compounds to assess their advantage over existing drugs.

Risk factors for cardiopulmonary and respiratory arrest in medical and surgical hospital patients on opioid analgesics and sedatives

BACKGROUND

Opioid induced respiratory depression is a known cause of preventable death in hospitals. Medications with sedative properties additionally potentiate opioid-induced respiratory and sedative effects, thereby elevating the risk for adverse events. The goal of this study was to determine what specific factors increase the risk of in-hospital cardiopulmonary and respiratory arrest (CPRA) in medical and surgical patients on opioid and sedative therapy.

METHODS

The present study analyzed 14,504,809 medical inpatient and 6,771,882 surgical inpatient discharges reported into the Premier database from 2008 to 2012. Patients were divided in four categories: on opioids; on sedatives; on both opioids and sedatives; and on neither opioids nor sedatives.

RESULTS

During hospital admission, 57% of all medical patients and 90% of all surgical patients were prescribed opioids, sedatives, or both. Surgical patients had a higher incidence of CPRA than medical patients (6.17 vs. 3.77 events per 1000 admissions; Relative Risk: 1.64 [95%CI: 1.62-1.66; p<0.0001). Opioids and sedatives were found to be independent predictors of CPRA (adjusted OR of 2.24 [95%CI: 2.18-2.29] for opioids and adjusted OR 1.80 [95%CI: 1.75-1.85] for sedatives in medical patients, and adjusted OR of 1.12 [95%CI: 1.07-1.16] for opioids and adjusted OR of 1.58 [95%CI: 1.51-1.66] for sedatives in surgical patients), with the highest risk in groups who received both types of medications (adjusted OR of 3.83 [95% CI: 3.74-3.92] in medical patients, and adjusted OR of 2.34 [95% CI: 2.25-2.42] in surgical patients) compared with groups that received neither type of medication. The common risk factors of CPRA in medical and surgical patients receiving both opioids and sedatives were Hispanic origin, mild liver disease, obesity, and COPD. Additionally, medical and surgical groups had their own unique risk factors for CPRA when placed on opioid and sedative therapy.

CONCLUSIONS

Opioids and sedatives are independent and additive predictors of CPRA in both medical and surgical patients. Receiving both classes of medications further exacerbates the risk of CPRA for these patients. By identifying groups at risk among medical and surgical in-hospital patients, this study provides a step towards improving our understanding of how to use opioid and sedative medications safely, which may influence our treatment strategies and outcomes. More precise monitoring of selected high-risk patients may help prevent catastrophic cardiorespiratory complications from these medications. As a retrospective administrative database analysis, this study does not establish the causality or the temporality of the events but rather draws statistically significant associations between the clinical factors and outcomes.

Estimating the Direct Costs of Outpatient Opioid Prescriptions: A Retrospective Analysis of Data from the Rhode Island Prescription Drug Monitoring Program

BACKGROUND

Overuse and misuse of prescription opioids is associated with increased morbidity and mortality and places a significant cost burden on health systems.

OBJECTIVE

To estimate annual statewide spending for prescription opioids in Rhode Island.

METHODS

A cross-sectional study of opioids dispensed from retail pharmacies using data from the Rhode Island Prescription Drug Monitoring Program (PDMP) was performed. The study sample consisted of 651,227 opioid prescriptions dispensed to 197,062 patients between January 1, 2015, and December 31, 2015. The mean, median, and total cost of opioid use was estimated using prescription dispensings and patients as units of analysis. A generalized linear model with gamma distribution with an identity link function, and separately with a log link function, was used to estimate the absolute and relative differences in per-patient annual adjusted average opioid prescription cost, respectively, by potential predictors.

RESULTS

The estimated 2015 annual expenditure for opioid prescriptions in Rhode Island was $44,271,827. The average and median costs of an opioid prescription were $67.98 (SD $210.91) and $21.08 (quartile 1 to quartile 3 = $7.65-$47.51), respectively. Prescriptions for branded opioid products accounted for $17,380,279.05, which was approximately 39.3% of overall spending, although only 6% of all opioids dispensed were for branded drugs. On average, patients aged 45-54 years and 55-64 years had overall adjusted spending for opioids that were 1.53 (95% CI = 1.49-1.57) and 1.75 (95% CI = 1.71-1.80) times higher than patients aged 65 years and older, respectively. Per patient Medicaid and Medicare average annual spending for opioid prescriptions were 1.19 (95% CI = 1.16-1.22) and 2.01 (95% CI = 1.96-2.06) times higher than commercial insurance spending, respectively. Annual opioid prescription spending was 2.01 (95% CI = 1.98-2.04) and 1.50 (95% CI = 1.45-1.55) times higher among patients who also had at least 1 dispensing of a benzodiazepine or sympathomimetic stimulant, respectively. Average total spending for prescription opioids per patient increased with the average daily dosage: from 3-fold for patients using 50-90 morphine milligrams equivalent (MME) daily to 22-fold for those receiving 90 or more MME daily compared with those receiving less than 50 MME daily.

CONCLUSIONS

This study provides the first estimate of the statewide direct cost burden of prescription opioid use using PDMP data and standardized pricing benchmarks. Total annual cost increased with age up to 65 years, mean daily dose, and concurrent use of benzodiazepines or stimulants. Commercial insurance bore the majority of the cost of prescription opioid use, but cost per patient was highest among Medicare beneficiaries. In addition to reducing harms associated with opioid overuse and misuse, substantial cost savings could be realized by reducing unnecessary opioid use, especially among middle-aged adults.

DISCLOSURES

This study was funded by the Rhode Island Department of Health. Aroke and Kogut report grants from the Rhode Island Department of Health during this study. Kogut is partially supported by Institutional Development Award Number U54GM115677 from the National Institute of General Medical Sciences of the National Institutes of Health, which funds Advance Clinical and Translational Research (Advance-CTR). Koziol reports grants from the Centers for Disease Control and Prevention during this study. The other authors have nothing to disclose. The content of this study is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Study concept and design were contributed by Koziol, Ragosta, and Kogut, along with Aroke. Koziol, Ragosta, Aroke, and Kogut collected the data, and data interpretation was performed by Aroke, Buchanan, Wen, and Kogut. The manuscript was primarily written by Aroke, along with Buchanan and Kogut, and revised by Aroke, Buchanan, Wen, and Kogut.