Enteral Sedation in Patients Requiring Mechanical Ventilation During an Intravenous Analgesic and Sedative Shortage

Background: There is a paucity of data evaluating the use of enteral sedation in mechanical ventilation. A sedative shortage resulted in the use of this approach. Purpose: To evaluate the feasibility of using enteral sedatives to decrease intravenous (IV) analgesia and sedative requirements. Materials/Methods: This single-center, retrospective, observational study compared two groups of patients admitted to the ICU who were mechanically ventilated. One group received a combination of enteral and IV sedatives and the second group received IV monotherapy. Linear mixed model (LMM) analyses were performed to assess the impact of enteral sedatives on IV fentanyl equivalents, IV midazolam equivalents, and propofol. Mann-Whitney U tests were performed on percent of days at goal for Richmond Agitation and Sedation Scale (RASS) and critical care pain observation tool (CPOT) scores. Results: One hundred and four patients were included. The average cohort age was 62 years and 58.7% were male. The median length of mechanical ventilation was 7.1 days and the median length of stay was 11.9 days. The LMM estimated that enteral sedatives reduced IV fentanyl equivalents received per patient by an average of 305.6 mcg/day (P = .04), although did not significantly decrease midazolam equivalents or propofol. There was no statistically significant difference in CPOT scores (P = .57 and P = .46 respectively), however RASS scores in the enteral sedation group were more often at goal (P = .03); oversedation occurred more in the non-enteral sedation group (P = .018). Conclusion: Enteral sedation may be a possible way to decrease IV analgesia requirements during periods of shortage.

Not Carfentanil-A Case of Unexpected Xylazine Detection

Historically, xylazine has been utilized in veterinary medicine for decades as an anesthetic and analgesic sedative to facilitate safe handling, diagnostic testing, and surgical procedures in large animals. Currently, xylazine is an emerging threat to human health. It has been detected in the illicit drug supply chain, often as an adulterant. It has been more commonly added to illicit substances, most notably fentanyl, by drugmakers to enhance drug effect. End users are often unaware of its presence. This is alarming given the large number of xylazine-involved overdose deaths while laboratory detections are deficient and reversal agents are absent. Herein, we present the first documented case of xylazine identified via gas chromatography-tandem mass spectrometry at University of California Davis Health despite a peculiarly mild clinical presentation. We hope to increase awareness of this potentially fatal adulterant that is often missed in evaluation and engender further opportunities to study this ongoing issue.

Erector spinae plane block in dogs undergoing hemilaminectomy: A prospective randomized clinical trial

OBJECTIVE

To compare the perioperative cumulative opioid consumption and the incidence of cardiovascular complications in dogs undergoing hemilaminectomy in which either an erector spinae plane (ESP) block or systemic opioids were administered.

STUDY DESIGN

Prospective randomized clinical trial.

ANIMALS

A total of 60 client-owned dogs.

METHODS

Dogs were randomized to one of three groups: an ESP block (group ESP), a constant rate infusion of fentanyl (group FNT, positive control) or a single dose of methadone as premedication (group MTD, negative control). Intraoperative nociceptive response was treated with fentanyl [1 μg kg-1, intravenously (IV)] boli. Before closure of the surgical site, morphine (0.1 mg kg-1) was applied to the dura mater. The cumulative dose of opioids was recorded and compared between groups. The incidence of intraoperative bradycardia and/or hypotension and the time to extubation were compared between groups. The short form of the Glasgow Composite Pain Scale (SF-GCPS) was used to score nociception before anaesthetic induction and 1, 2, 6, 12,18 and 24 hours postoperatively. Methadone 0.2 mg kg-1 was administered IV if the SF-GCPS score was ≥ 5.

RESULTS

Group MTD required more intraoperative rescue analgesia than groups ESP (p = 0.008) and FNT (p = 0.001). The total cumulative intraoperative dose of fentanyl was higher in groups FNT (p < 0.0001) and MTD (p = 0.002) than in group ESP. The incidence of cardiovascular complications was similar between groups. Extubation time was longer in group MTD (p = 0.03). Postoperatively, the time to first rescue analgesia was longer in group ESP than in group MTD (p = 0.03). The cumulative postoperative opioid consumption and pain scores were similar between groups.

CONCLUSIONS AND CLINICAL RELEVANCE

The ESP block resulted in a reduced intraoperative opioid consumption compared with the control positive and negative groups.

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

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

Perioperative analgesic effects of the erector spinae plane block with bupivacaine or bupivacaine-dexmedetomidine in dogs undergoing hemilaminectomy: A randomized controlled trial

Objective

To compare the perioperative opioid requirements among dogs receiving an erector spinae plane (ESP) block with bupivacaine, with or without dexmedetomidine, and a control group.

Animals and procedure

Thirty client-owned, healthy adult dogs undergoing hemilaminectomy were included in this randomized, prospective, blinded clinical study. Dogs were randomly assigned to 1 of 3 treatment groups: Group B, ESP block with bupivacaine; Group BD, ESP block with bupivacaine and dexmedetomidine; and Group C, control. Rescue intra- and postoperative analgesia consisted of fentanyl and methadone, respectively. Postoperative pain was evaluated using the short form of the Glasgow Composite Measure Pain Scale (CMPS-SF).

Results

In Group BD, 0/10 dogs required intraoperative fentanyl, compared to 9/10 in Group C (P < 0.001), whereas 1/10 required postoperative methadone, compared to 9/10 in Group B (P = 0.003) and 10/10 in Group C (P < 0.001). The total amount of intraoperative fentanyl (μg/kg) was 0 (0 to 4) in Group B and 0 (0 to 0) in BD, compared to 6 (0 to 8) in C (P = 0.004 and P < 0.001, respectively). Postoperative methadone (mg/kg) required during the first 12 h was 0.5 (0 to 1.4) in Group B (P = 0.003) and 0 (0 to 0) in BD (P < 0.001), compared to C (P = 0.003 and P < 0.001, respectively).

Conclusion

An ESP block with bupivacaine, with or without dexmedetomidine, was associated with a reduction in perioperative opioid consumption and provided effective acute pain control.

A Comparison of Three Anesthetic Drug Combinations for Use in Inducing Surgical Anesthesia in Female Guinea Pigs (Cavia porcellus)

Guinea pigs are often used in translational research, but providing them with safe and effective anesthesia is a challenge. Common methods like inhalant anesthesia and injectable ketamine/xylazine induce surgical anesthesia but can negatively affect cardiovascular, respiratory, and thermoregulatory systems and complicate the interpretation of research outcomes. Several alternative anesthetic regimens have been investigated, but none have consistently achieved a surgical plane of anesthesia. Therefore, identifying an anesthetic regimen that achieves a stable state of the surgical plane of anesthesia while preserving cardiorespiratory function would be a valuable contribution. To address this issue, we compared the efficacy of 3 anesthetic combinations in female Dunkin-Hartley guinea pigs: 1) alfaxalone, dexmedetomidine, and fentanyl (ADF); 2) alfaxalone, midazolam, and fentanyl (AMF); and 3) alfaxalone, midazolam, fentanyl, and isoflurane (AMFIso). We monitored anesthetic depth, heart rate, oxygenation, respiratory rate, respiratory effort, blood pressure, and body temperature every 15 min from injection to recovery. We also recorded the time to loss of righting reflex, duration of anesthesia, and time to achieve a surgical plane. The results showed no statistically significant differences in induction and recovery times among the groups. In the AMFIso group, 100% of the animals achieved a surgical plane of anesthesia, whereas only 10% of the animals in the AMF group reached that level. None of the animals in ADF group reached a surgical plane of anesthesia. Respiratory rate was significantly lower in the AMFIso as compared with the ADF group (P < 0.001) but was not different between the AMF and ADF groups. Temperature was significantly lower in the AMFIso group as compared with both the ADF and AMF groups (P < 0.001). In conclusion, both combinations of solely injectable anesthetics assessed in this study can be used for short, nonpainful procedures without significant cardiorespiratory depression. However, for mildly to moderately painful surgical procedures, the addition of an inhalant anesthetic like isoflurane is necessary for female guinea pigs.

Perceptions of fentanyl among African Americans who misuse opioids: implications for risk reduction

BACKGROUND

Fentanyl is a powerful synthetic opioid that is 50 times more powerful than heroin and has become ubiquitous in the illicit drug supply in the USA. Studies show that among people who use drugs, fentanyl is sometimes viewed as a desirable substance due to its high potency and low cost, while others have an unfavorable perception because of its association with overdose. Unfortunately, studies on the perceptions of fentanyl are relatively rare and existing studies tend to rely on samples with little African American representation. The objective of this study, therefore, was to identify and describe perceptions of fentanyl among African Americans who misuse opioids, while capturing their motivations for seeking out or avoiding fentanyl.

METHODS

In-depth interviews (n = 30) were conducted with a sample of African American adults who misuse opioids in Southwest Florida between August 2021 and February 2022. Audiotapes of interviews were transcribed, coded, and thematically analyzed.

RESULTS

Analyses revealed the presence of three subtypes of fentanyl-related perceptions: (1) fentanyl as an avoided adulterant, (2) fentanyl as a tolerated adulterant, and (3) fentanyl as a drug of choice.

CONCLUSIONS

These findings show that African Americans' perceptions of fentanyl are not monolithic and suggest the distribution of fentanyl test strips and naloxone may be an effective risk reduction strategy. Given that most studies on fentanyl rely on quantitative data from drug seizures and death certificates, this study uniquely contributes to the literature by capturing the voices of African Americans who use drugs.

Continuous fentanyl administration and spontaneous withdrawal decreases home cage wheel running in rats with and without hindpaw inflammation

Fentanyl is a potent analgesic with a rapid onset and short half-life that make it a useful treatment for pain and a lethal drug of abuse. The present study used voluntary home cage wheel running to assess the effect of hindpaw inflammation, fentanyl administration, and spontaneous fentanyl withdrawal. Fentanyl (0.32 or 1.0 mg/kg/day) or placebo osmotic pumps were implanted subcutaneously and rats received an intraplantar injection of Complete Freund's Adjuvant (CFA) or saline. Rats with hindpaw inflammation caused by CFA administration were less active than rats injected with saline into the hindpaw. The antinociceptive effect of 0.32 mg/kg/day of fentanyl was evident as a recovery of wheel running in these rats. Administration of 1 mg/kg/day of fentanyl almost completely inhibited wheel running during the first day in rats with and without hindpaw inflammation. Wheel running increased each subsequent day until the pumps were surgically removed after day 3. Withdrawal from 0.32 or 1 mg/kg/day of fentanyl caused a decrease in wheel running that lasted 2 days in rats without hindpaw inflammation. In contrast, withdrawal was only evident following termination of 1 mg/kg/day of fentanyl in rats with hindpaw inflammation. This decrease in running seemed to persist beyond the 3 days of assessment. These data demonstrate that fentanyl can either depress or restore activity depending on the dose and pain condition. Moreover, termination of 3 days of continuous fentanyl administration resulted in a dose and time dependent decrease in wheel running consistent with opioid withdrawal.

The motives and methods of methamphetamine and 'heroin' co-use in West Virginia

BACKGROUND

Opioid and methamphetamine co-use is increasing across the USA with overdoses involving these drugs also rising. West Virginia (WV) has led the US in opioid overdose death rates since at least 2013 and rising co-use of methamphetamine with opioids has played a greater role in deaths over the last 5 years.

METHODS

This study used rapid ethnography to examine methods and motivations behind opioids and methamphetamine co-use from the viewpoint of their consumers. Participants (n = 30) were people who injected heroin/fentanyl also using methamphetamine who participated in semi-structured interviews.

RESULTS

We found multiple methods of co-using opioids and methamphetamine, whether alternately or simultaneously and in varying order. Most prioritized opioids, with motives for using methamphetamine forming three thematic categories: 'intrinsic use', encompassing both inherent pleasure of combined use greater than using both drugs separately or for self-medication of particular conditions; 'opioid assisting use' in which methamphetamine helped people manage their existing heroin/fentanyl use; and 'reluctant or indifferent use' for social participation, reflecting methamphetamine's low cost and easy availability.

CONCLUSIONS

Methamphetamine serves multiple functions among people using opioids in WV. Beliefs persist that methamphetamine can play a role in preventing and reversing opioid overdose, including some arguments for sequential use being protective of overdose. 'Reluctant' uptake attests to methamphetamine's social use and the influence of supply. The impact on overdose risk of the many varied co-use patterns needs further investigation.

Effect of the glucocorticoid receptor antagonist PT150 on acquisition and escalation of fentanyl self-administration following early-life stress

There is comorbidity between posttraumatic stress disorder (PTSD) and opioid use disorder (OUD), perhaps because PTSD-like stressful experiences early in life alter the hypothalamic-pituitary-adrenal stress axis to increase the risk for OUD. The present study determined if the glucocorticoid receptor antagonist PT150 reduces the escalation of fentanyl intake in rats exposed to a "two-hit" model of early-life stress (isolation rearing and acute stress). Male and female rats were raised during adolescence in either isolated or social housing and then were given either a single acute stress (restraint and cold-water swim) or control treatment in young adulthood. Rats were then treated daily with PT150 (50 mg/kg, oral) or placebo and were tested for acquisition of fentanyl self-administration in 1-hr sessions, followed by escalation across 6-hr sessions. Regardless of PT150 treatment or sex, acquisition of fentanyl self-administration in 1-hr sessions was greater in isolate-housed rats compared to social-housed rats; the acute stress manipulation did not have an effect on self-administration even though it transiently increased plasma corticosterone levels. During the 6-hr sessions, escalation of fentanyl was observed across all treatment groups; however, there was a significant PT150 Treatment × Sex interaction. While males self-administered more than females overall, PT150 decreased intake in males and increased intake in females, thus negating the sex difference. Although PT150 may serve as an effective treatment for reducing the risk of OUD following early-life stress in males, further work is needed to determine the mechanism underlying the differential effects of PT150 in males and females. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Nebulized fentanyl for respiratory symptoms in patients with COVID-19 (ventanyl trial)

Patients with coronavirus disease (COVID-19) commonly experience distressing and challenging respiratory symptoms. Interventions such as oxygen therapy, oral opiates, and traditional nebulizers like ipratropium bromide and salbutamol are variable in their efficacy, and therapy responses in patients are difficult to predict. The purpose of this study is to investigate the efficacy of nebulized fentanyl citrate on dyspnea, cough, and throat pain in patients with COVID-19 and evaluate the safety with any potential adverse events.In COVID-19, about 59% of patients will exhibit cough, 35% generalized body ache and sore throat, and 31% dyspnea. Some methods such as nebulized lidocaine, magnesium sulfate, and systemic opioids have been used to manage the respiratory symptoms. It has been previously shown that fentanyl nebulizer has beneficial effect in improving shortness of breath in patients with chronic obstructive pulmonary disease. The proposed theory behind that was that fentanyl decreased the rate of spontaneous respiratory rate, diminished the brain stem chemoreceptor response to hypoxia and hypercarbia, in addition to exhibiting a modulating effect on the brain stem. Therefore, we hypothesize that nebulized fentanyl has superior effect in improving shortness of breath and relieving cough compared to normal saline, in addition to its advantageous throat pain relief, while exhibiting fewer side effects in patients with COVID 19 infection. Therefore, this phase-III, randomized, comparative, parallel assignment, single-blinded clinical trial aims at assessing the efficacy and safety of nebulized fentanyl to suppress cough, improve breathlessness, and relieve throat pain in patients with COVID-19.

Predicting Maternal-Fetal Disposition of Fentanyl Following Intravenous and Epidural Administration Using Physiologically Based Pharmacokinetic Modeling

Fentanyl is an opioid analgesic used to treat obstetrical pain in parturient women through epidural or intravenous route, and unfortunately can also be abused by pregnant women. Fentanyl is known to cross the placental barrier, but how the route of administration and time after dosing affects maternal-fetal disposition kinetics at different stages of pregnancy is not well characterized. To address this knowledge gap, we developed a maternal-fetal physiologically based pharmacokinetic (mf-PBPK) model for fentanyl to evaluate the feasibility to predict the maternal and fetal plasma concentration-time profiles of fentanyl after various dosing regimens. As fentanyl is typically given via the epidural route to control labor pain, an epidural dosing site was developed using alfentanil as a reference drug and extrapolated to fentanyl. Fetal hepatic clearance of fentanyl was predicted from CYP3A7-mediated norfentanyl formation in fetal liver microsomes (intrinsic clearance = 0.20 ± 0.05 µl/min/mg protein). The developed mf-PBPK model successfully captured fentanyl maternal and umbilical cord concentrations after epidural dosing and was used to simulate the concentrations after intravenous dosing (in a drug abuse situation). The distribution kinetics of fentanyl were found to have a considerable impact on the time course of maternal:umbilical cord concentration ratio and on interpretation of observed data. The data show that mf-PBPK modeling can be used successfully to predict maternal disposition, transplacental distribution, and fetal exposure to fentanyl. SIGNIFICANCE STATEMENT: This study establishes the modeling framework for predicting the time course of maternal and fetal exposures of fentanyl opioids from mf-PBPK modeling. The model was validated based on fentanyl exposure data collected during labor and delivery after intravenous or epidural dosing. The results show that mf-PBPK modeling is a useful predictive tool for assessing fetal exposures to fentanyl opioid therapeutic regimens and potentially can be extended to other drugs of abuse.

Comparison of epidural, spinal, and saddle block for holmium laser enucleation of prostate (HoLEP): A prospective randomized, comparative study

BACKGROUND

Holmium laser enucleation of the prostate (HoLEP) has become an important treatment modality for benign prostate hypertrophy. The aim of the present study was to compare regional anesthesia methods for HoLEP operation and to determine the optimal technique.

METHODS

Sixty patients with American Society of Anesthesiologists scores of I-III were randomly allocated into 3 groups. Patients in group E received an epidural block with 75 mg of bupivacaine plus 50 μg of fentanyl. In group S, 15 mg of bupivacaine and 50 μg fentanyl were used for spinal anesthesia. In group SA, patients received saddle block with 15 mg of bupivacaine and 50 μg of fentanyl.

RESULTS

Time to T10 dermatome block and to maximal level block were longest in group E (P < .05), and maximal sensorial block level was higher in group E than group SA (P < .05). There was a significant difference in postoperative motor block, but no difference in systolic blood pressure and heart rate.

CONCLUSION

Among 3 techniques, saddle block might be preferable in HoLEP because an adequate sensorial level was achieved with lower motor block and stable hemodynamics.

Influence of ketamine versus fentanyl on pain relief for pediatric orthopedic emergencies: A meta-analysis of randomized controlled studies

INTRODUCTION

The comparison of ketamine with fentanyl for pain control of pediatric orthopedic emergencies remains controversial. We conduct a systematic review and meta-analysis to explore the influence of ketamine versus fentanyl on pain management among pediatric orthopedic emergencies.

METHODS

We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through September 2020 for randomized controlled trials assessing the effect of ketamine versus fentanyl on pain management for pediatric orthopedic emergencies.

RESULTS

Five randomized controlled trials are included in the meta-analysis. Overall, compared with fentanyl for pediatric orthopedic emergencies, ketamine led to similar change in pain scores at 15 to 20 minutes (standard mean difference = -0.05; 95% confidence interval [CI] = -0.38 to 0.28; P = .77) and 30 minutes (standard mean difference = 0.11; 95% CI = -0.20 to 0.42; P = .49), as well as rescue analgesia (RR = 0.90; 95% CI = 0.54 to 1.51; P = .69), but revealed the increase in nausea/vomiting (RR = 2.65; 95% CI = 1.13 to 6.18; P = .02) and dizziness (RR = 3.83; 95% CI = 1.38 to 10.60; P = .01).

CONCLUSIONS

Ketamine may be similar to fentanyl in terms of the analgesic efficacy for pediatric orthopedic emergencies.

Intravenous Infusion of Fentanyl Has No Effect on Blood Concentration of Tacrolimus in Patients Receiving Hematopoietic Stem-Cell Transplantation

BACKGROUND

Both tacrolimus (TAC) and fentanyl are frequently used in patients receiving allogeneic hematopoietic stem-cell transplantation. A recently published report demonstrated that fentanyl can reduce the total body clearance of TAC; however, most patients in this study were administered concomitantly with azole antifungal agents, which are known to be strong inhibitors of CYP3A. Hence, the exact effect of fentanyl on TAC pharmacokinetics was unclear. In the current study, the authors retrospectively investigated the pharmacokinetic interaction between TAC and fentanyl in patients who were not concomitantly administered drugs that affect TAC metabolism.

METHODS

Patients with continuous infusion of TAC and fentanyl after hematopoietic stem-cell transplantation at the Tokyo Medical and Dental University between January 2014 and December 2018 were enrolled. The total body clearance of TAC was compared before and after the initiation or discontinuation of fentanyl.

RESULTS

Thirty patients (24 men and 6 women; median age, 11 years) were screened for their eligibility. Twenty-eight patients were enrolled for evaluating the effects of the fentanyl initiation on TAC pharmacokinetics; 2 patients were excluded because of the absence of data related to the TAC blood concentrations or the concomitant use of azole antifungals. Twenty patients were enrolled for investigating the effects of fentanyl discontinuation on TAC pharmacokinetics, whereas 10 patients were excluded because of the absence of data related to the blood concentration of TAC or the additional administration of azole antifungals. Furthermore, the total body clearance of TAC was not significantly affected by the initiation or discontinuation of fentanyl, although there were large interindividual variations. In addition, the results remained the same even when the analysis was performed independently for adults and children.

CONCLUSIONS

Intravenous infusion of fentanyl does not affect the pharmacokinetics of TAC.

Functional Profile of Systemic and Intrathecal Cebranopadol in Nonhuman Primates

BACKGROUND

Cebranopadol, a mixed nociceptin/opioid receptor full agonist, can effectively relieve pain in rodents and humans. However, it is unclear to what degree different opioid receptor subtypes contribute to its antinociception and whether cebranopadol lacks acute opioid-associated side effects in primates. The authors hypothesized that coactivation of nociceptin receptors and μ receptors produces analgesia with reduced side effects in nonhuman primates.

METHODS

The antinociceptive, reinforcing, respiratory-depressant, and pruritic effects of cebranopadol in adult rhesus monkeys (n = 22) were compared with μ receptor agonists fentanyl and morphine using assays, including acute thermal nociception, IV drug self-administration, telemetric measurement of respiratory function, and itch-scratching responses.

RESULTS

Subcutaneous cebranopadol (ED50, 2.9 [95% CI, 1.8 to 4.6] μg/kg) potently produced antinociception compared to fentanyl (15.8 [14.6 to 17.1] μg/kg). Pretreatment with antagonists selective for nociceptin and μ receptors, but not δ and κ receptor antagonists, caused rightward shifts of the antinociceptive dose-response curve of cebranopadol with dose ratios of 2 and 9, respectively. Cebranopadol produced reinforcing effects comparable to fentanyl, but with decreased reinforcing strength, i.e., cebranopadol (mean ± SD, 7 ± 3 injections) versus fentanyl (12 ± 3 injections) determined by a progressive-ratio schedule of reinforcement. Unlike fentanyl (8 ± 2 breaths/min), systemic cebranopadol at higher doses did not decrease the respiratory rate (17 ± 2 breaths/min). Intrathecal cebranopadol (1 μg) exerted full antinociception with minimal scratching responses (231 ± 137 scratches) in contrast to intrathecal morphine (30 μg; 3,009 ± 1,474 scratches).

CONCLUSIONS

In nonhuman primates, the μ receptor mainly contributed to cebranopadol-induced antinociception. Similar to nociceptin/μ receptor partial agonists, cebranopadol displayed reduced side effects, such as a lack of respiratory depression and pruritus. Although cebranopadol showed reduced reinforcing strength, its detectable reinforcing effects and strength warrant caution, which is critical for the development and clinical use of cebranopadol.

EDITOR’S PERSPECTIVE

Escalation and reinstatement of fentanyl self-administration in male and female rats

RATIONALE

Escalation of drug intake and craving are two DSM-5 hallmark symptoms of opioid use disorder (OUD).

OBJECTIVES

This study determined if escalation of intake as modeled by long access (LgA) self-administration (SA) and craving measured by reinstatement are related.

METHODS

Adult male and female Sprague-Dawley rats were trained to self-administer fentanyl across 7 daily 1-h short access (ShA) sessions, followed by 21 SA sessions of either 1- or 6-h duration (ShA or LgA). Following 14 1-h extinction sessions, Experiment 1 assessed reinstatement induced by either fentanyl (10 or 30 µg/kg) or yohimbine (1 or 2 mg/kg), and Experiment 2 assessed reinstatement induced by a drug-associated cue light.

RESULTS

Females acquired fentanyl SA faster than males. When shifted to LgA sessions, LgA rats escalated fentanyl intake, but ShA rats did not; no reliable sex difference in the rate of escalation was observed. In extinction, compared to ShA rats, LgA rats initially responded less and showed less decay of responding across sessions. A priming injection of fentanyl induced reinstatement, with LgA rats reinstating more than ShA rats at the 30 µg/kg dose. Yohimbine (1 mg/kg) also induced reinstatement, but there was no effect of access group or sex. With cue-induced reinstatement, LgA females reinstated less than LgA males and ShA females.

CONCLUSION

Among the different reinstatement tests assessed, escalation of fentanyl SA increased only drug-primed reinstatement, suggesting a limited relationship between escalation of drug intake and craving (reinstatement) for OUD.

Comparison of efficacy between palonosetron-midazolam combination and palonosetron alone for prevention of postoperative nausea and vomiting in patients undergoing breast surgery and patient controlled analgesia: A prospective, randomized, double-blind study: A CONSORT-compliant study

BACKGROUND

Postoperative nausea and vomiting (PONV) is a common complaint in patients following general anesthesia. Various antiemetics, including 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists, are effective but still have limited efficacy. Therefore, combination therapy is preferable to using a single drug alone in high-risk patients. We performed a comparative study on the antiemetic effect of palonosetron, a 5-HT3 receptor antagonist, monotherapy vs palonosetron-midazolam combination therapy for the prevention of PONV.

METHODS

A total of 104 female patients scheduled for breast cancer surgery were enrolled. They were randomly divided into 2 groups, a palonosetron monotherapy group (group P) and palonosetron-midazolam combination therapy group (group PM). Both groups received 0.075 mg palonosetron intravenously after induction of anesthesia. Patient-controlled analgesia (PCA) was applied according to the allocated group. Intravenous (IV)-PCA in group P consisted of fentanyl 20 μg/kg plus normal saline (total volume: 100 ml); IV-PCA in group PM consisted of fentanyl 20 μg/kg plus midazolam 4 mg plus normal saline (total volume: 100 ml). Efficacy parameters were collected during 0 to 1, 1 to 6, 6 to 24, and 24 to 48 hours postoperative time intervals. These measures included complete response (defined as no PONV and no rescue anti-emetic use) rate, incidence of PONV, sedation score, rescue antiemetic use, rescue analgesic use, and numerical rating scale (NRS) for pain. The complete response rate during the 0 to 24 hours interval was analyzed as the primary outcome.

RESULTS

Although the complete response rate between 0 and 24 hours was higher in group PM (42.3% and 48.1% in group P and PM, respectively), there was no statistically significant difference (P = .55). The complete response rates in other time intervals were not different between the 2 groups as well. The sedation score and NRS score also showed no differences between the 2 groups.

CONCLUSIONS

The combination therapy of palonosetron with midazolam did not lead to a greater reduction in the incidence of PONV than monotherapy in patients undergoing breast surgery and receiving IV-PCA containing fentanyl.

A novel dual agonist of glucagon-like peptide-1 receptors and neuropeptide Y2 receptors attenuates fentanyl taking and seeking in male rats

There has been a dramatic increase in illicit fentanyl use in the United States over the last decade. In 2018, more than 31,000 overdose deaths involved fentanyl or fentanyl analogs, highlighting an urgent need to identify effective treatments for fentanyl use disorder. An emerging literature shows that glucagon-like peptide-1 receptor (GLP-1R) agonists attenuate the reinforcing efficacy of drugs of abuse. However, the effects of GLP-1R agonists on fentanyl-mediated behaviors are unknown. The first goal of this study was to determine if the GLP-1R agonist exendin-4 reduced fentanyl self-administration and the reinstatement of fentanyl-seeking behavior, an animal model of relapse, in rats. We found that systemic exendin-4 attenuated fentanyl taking and seeking at doses that also produced malaise-like effects in rats. To overcome these adverse effects and enhance the clinical potential of GLP-1R agonists, we recently developed a novel dual agonist of GLP-1Rs and neuropeptide Y2 receptors (Y2Rs), GEP44, that does not produce nausea-like behavior in drug-naïve rats or emesis in drug-naïve shrews. The second goal of this study was to determine if GEP44 reduced fentanyl self-administration and reinstatement with fewer adverse effects compared to exendin-4 alone. In contrast to exendin-4, GEP44 attenuated opioid taking and seeking at a dose that did not suppress food intake or produce adverse malaise-like effects in fentanyl-experienced rats. Taken together, these findings indicate a novel role for GLP-1Rs and Y2Rs in fentanyl reinforcement and highlight a potential new therapeutic approach to treating opioid use disorders.

Perioperative Opioid Consumption is Not Reduced in Cyanotic Patients Presenting for the Fontan Procedure

Adequate pain control is a critical component of the perioperative approach to children undergoing repair of congenital heart disease (CHD). The impact of specific anatomic and physiologic disturbances on the management of analgesia has been largely unexplored at the present time. Studies in other pediatric populations have found an association between chronic hypoxemia and an increased sensitivity to the effects of opioid medications. The purpose of this retrospective study was to examine perioperative opioid administration and opioid-associated adverse effects in children undergoing surgical repair of CHD, with a comparison between patients with and without chronic preoperative cyanosis. Patients between the ages of 2 and 5 years whose tracheas were extubated in the operating room were included and were classified in the cyanotic group if they presented for the Fontan completion. The primary outcomes of interest were intraoperative and postoperative opioid administration. Secondary outcomes included pain scores and opioid-related side effects. The study cohort included 156 patients. Seventy-one underwent the Fontan procedure, twelve of which were fenestrated. Fontan patients received fewer opioids intraoperatively (11.33 µg/kg fentanyl equivalents versus 12.56 µg/kg, p = 0.03). However, there were no differences with regards to opioid consumption postoperatively and no correlation between preoperative oxygen saturation and total opioid administration. There were no differences between groups with regards to the respiratory rate nadir, postoperative pain scores, or the incidence of opioid-related side effects. In contrast to other populations with chronic hypoxemia exposure, children with cyanotic CHD did not appear to have increased sensitivity to the effects of opioid medications.

Comparison of opioid local anesthetic combination regimens using the number of self-administrated boluses in patient-controlled epidural analgesia after cesarean section: A retrospective single-center study

ABSTRACT

The aim of this study was to assess the efficacy of combined opioids by comparing four regimens of patient-controlled epidural analgesia (PCEA) after cesarean section.Parturient patients who underwent elective or emergent cesarean section under combined spinal and epidural anesthesia from April 2013 to March 2016 were retrospectively analyzed. Based on PCEA, they were assigned to one of 4 groups: local anesthetic alone (LA), epidural single morphine administration during surgery followed by local anesthetic alone (M), local anesthetic combined with fentanyl 10 μg/h (F10), or local anesthetic combined with fentanyl 20 μg/h (F20). The primary outcome was the number of PCEA boluses used. Secondary outcomes included the use of rescue analgesia, postoperative nausea and vomiting, and postoperative pruritus.A total of 250 parturients were analyzed. Whereas the number of PCEA boluses in the LA group was significantly higher than in the other combined opioid groups on the day of surgery and postoperative day 1 (LA: 3 [1-6] and 7 [4-9] vs M: 2 [0-4] and 4 [0-7] vs F10: 1 [0-4] and 3 [0-6] vs F20: 1 [0-3] and 2 [0-8], P = .012 and 0.010, respectively), within the combined opioid groups, the number was not significantly different. Significantly fewer patients in the F20 group required rescue analgesia on postoperative day 1 and 2 (25 and 55%) than those in the M (66 and 81%) and F10 (62 and 66%) groups (P < .001 and P = .007, respectively). Postoperative nausea and vomiting and pruritus were significantly higher in the M group (P < .008 and P = .024, respectively).The results of the present study suggest that local anesthetic alone after a single administration of morphine, or local anesthetic combined with fentanyl 10 μg/h would generally be adequate for PCEA, whereas local anesthetic combined with fentanyl 20 μg/h would be suitable for conventional epidural analgesia.

Analgesic comparison of dezocine plus propofol versus fentanyl plus propofol for gastrointestinal endoscopy: A meta-analysis

INTRODUCTION

As the adjunctive anesthesia to propofol, both dezocine and fentanyl showed some potential for gastrointestinal endoscopy. This meta-analysis aimed to compare their efficacy and safety.

METHODS

PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases were systematically searched. Randomized controlled trials (RCTs) assessing the effect of dezocine versus fentanyl for the anesthesia of patients undergoing gastrointestinal endoscopy were included.

RESULTS

Five RCTs involving 677 patients were included in the meta-analysis. Overall, compared with fentanyl plus propofol for gastrointestinal endoscopy, dezocine plus propofol resulted in the reduction in propofol dose(mean difference [MD] = -11.72; 95% confidence interval [CI] = -22.83 to -0.61; P = .04), awakening time (std. MD = -1.79; 95% CI = -3.31 to -0.27; P = .02) and hypopnea (risk ratio [RR] = 0.16; 95% CI = 0.06-0.41; P = .0002), but had no remarkable effect on induction time (MD = 1.20; 95% CI = -0.98 to 3.39; P = .28), postoperative pain score (MD = -0.38; 95% CI = -1.00 to 0.24; P = .24), nausea or vomiting (RR = 0.45; 95% CI = 0.10-1.98; P = .29).

CONCLUSION

Dezocine plus propofol may be better for the anesthesia of gastrointestinal endoscopy than fentanyl plus propofol.

Comparison of lidocaine, huffing maneuver and combination of both in prevention fentanyl induced cough before induction of anesthesia: a double-blind, prospective, randomized placebo-controlled study

BACKGROUND

Intravenous bolus injection of fentanyl has been frequently reported to be associated with cough reflex during patient anesthesia. However, the search for the most effective protocol continues. This study aimed to compare the effect of reducing cough reflex after injection of fentanyl in a fusion protocol by combining the injections of lidocaine and Huffing maneuver and comparing with a placebo control group, before anesthesia induction.

METHODS

This prospective randomized controlled trial study was performed on 400 patients who were divided into four groups of combined protocol (group 1), lidocaine group (group 2), Huffing maneuver group (group 3), and the control receiving normal saline (group 4). Then patients were injected with 2. 5 μg /kg fentanyl and monitored for 2 min regarding their cough reflex, as well as the severity.

RESULTS

In group one, 9 patients (9%), in group two, 45 patients (45%), 22 patients (22%) in group three, and in group four, 75 patients (75%), developed cough reflex following fentanyl injection. Also, 13 patients (13%) developed moderate and 4 (4%) developed severe coughs in the control group reported, while no reports of severe or moderate cough were among the intervention groups. There was a significant difference between the intervention group and the control group both in terms of the rate and severity of the fentanyl-induced cough.

CONCLUSION

By using a combination of lidocaine injection along and Huffing maneuver, better results can be obtained in reducing the frequency, and also the severity of cough followed by fentanyl injection.

TRIAL REGISTRATION

The trial was registered with IRCT.IR (09/03/2018-No. IRCT20141009019470N74 ).

Determination of equi-analgesic doses of inhaled methoxyflurane versus intravenous fentanyl using the cold pressor test in volunteers: a randomised, double-blinded, placebo-controlled crossover study

Background

Inhaled methoxyflurane for acute pain relief has demonstrated an analgesic effect superior to placebo. Data comparing methoxyflurane to an opioid are needed. The aim of this study was to determine the equi-analgesic doses of inhaled methoxyflurane vs i.v. fentanyl. Both drugs have an onset within minutes and an analgesic effect of 20–30 min.

Methods

Twelve subjects were included in a randomised, double-blinded, placebo-controlled crossover study with four treatments: placebo (NaCl 0.9%), fentanyl 25 μg i.v., fentanyl 50 μg i.v., or inhaled methoxyflurane 3 ml. The subjects reported pain intensity using the verbal numeric rating scale (VNRS) from 0 to 10 during the cold pressor test (CPT). The CPT was performed before (CPT 1), 5 min (CPT 2), and 20 min (CPT 3) after drug administration.

Results

Inhaled methoxyflurane and fentanyl 25 μg reduced VNRS scores significantly compared with placebo at CPT 2 (–1.14 [estimated difference in VNRS between treatment groups with 95% confidence interval {CI}: –1.50 to –0.78]; –1.15 [95% CI: –1.51 to –0.79]; both P<0.001) and CPT 3 (–0.60 [95% CI: –0.96 to –0.24]; –0.84 [95% CI: –1.20 to –0.47]; both P<0.001). There were no significant differences between the two drugs. Methoxyflurane had significantly higher VNRS scores than fentanyl 50 μg at CPT 2 (0.90 [95% CI: 0.54–1.26]; P<0.001) and CPT 3 (0.57 [95% CI: 0.21–0.94]; P<0.001).

Conclusions

Inhaled methoxyflurane 3 ml was equi-analgesic to fentanyl 25 μg i.v. at CPT 2. Both resulted in significantly less pain than placebo. Fentanyl 50 μg i.v. demonstrated analgesia superior to methoxyflurane.

Clinical trial registration

NCT03894800

Tolerance to Opioid-Induced Respiratory Depression in Chronic High-Dose Opioid Users: A Model-Based Comparison With Opioid-Naïve Individuals

Chronic opioid consumption is associated with addiction, physical dependence, and tolerance. Tolerance results in dose escalation to maintain the desired opioid effect. Intake of high-dose or potent opioids may cause life-threatening respiratory depression, an effect that may be reduced by tolerance. We performed a pharmacokinetic-pharmacodynamic analysis of the respiratory effects of fentanyl in chronic opioid users and opioid-naïve subjects to quantify tolerance to respiratory depression. Fourteen opioid-naïve individuals and eight chronic opioid users received escalating doses of intravenous fentanyl (opioid-naïve subjects: 75-350 µg/70 kg; chronic users: 250-700 µg/70 kg). Isohypercapnic ventilation was measured and the fentanyl plasma concentration-ventilation data were analyzed using nonlinear mixed-effects modeling. Apneic events occurred in opioid-naïve subjects after a cumulative fentanyl dose (per 70 kg) of 225 (n = 3) and 475 µg (n = 6), and in 7 chronic opioid users after a cumulative dose of 600 (n = 2), 1,100 (n = 2), and 1,800 µg (n = 3). The time course of fentanyl's respiratory depressant effect was characterized using a biophase equilibration model in combination with an inhibitory maximum effect (Emax ) model. Differences in tolerance between populations were successfully modeled. The effect-site concentration causing 50% ventilatory depression, was 0.42 ± 0.07 ng/mL in opioid-naïve subjects and 1.82 ± 0.39 ng/mL in chronic opioid users, indicative of a 4.3-fold sensitivity difference. Despite higher tolerance to fentanyl-induced respiratory depression, apnea still occurred in the opioid-tolerant population indicative of the potential danger of high-dose opioids in causing life-threatening respiratory depression in all individuals, opioid-naïve and opioid-tolerant.

Early adolescent subchronic low-dose nicotine exposure increases subsequent cocaine and fentanyl self-administration in Sprague-Dawley rats

An exponential rise in nicotine-containing electronic-cigarette use has been observed during the period of adolescence. Preclinical studies have shown that nicotine exposure during early adolescence, but not adulthood, increases subsequent drug intake and reward. Although growing clinical trends highlight that stimulant use disorders are associated with the opioid epidemic, very few studies have assessed the effects of adolescent nicotine exposure on opioid intake. The objective of our current study is to develop a new animal model to assess the causal relationship of adolescent nicotine exposure on subsequent opioid intake. In this effort, we first replicate previous studies using a well-established 4-day nicotine paradigm. Rats are pretreated with a low dose of nicotine (2 × , 30 μg/kg/0.1 mL, intravenous) or saline during early adolescence (postnatal days 28-31) or adulthood (postnatal days 86-89). Following nicotine pretreatment on postnatal day 32 or postnatal day 90, animals underwent operant intravenous self-administration for the psychostimulant, cocaine [500 μg/kg/infusion (inf)] or the opioid, fentanyl (2.5 μg/kg/inf). We successfully show that adolescent but not adult, nicotine exposure enhances cocaine self-administration in male rats. Furthermore, we illustrate early adolescent but not adult nicotine exposure enhances fentanyl self-administration, independent of sex. Overall, our findings highlight that adolescence is a unique period of development that is vulnerable to nicotine-induced enhancement for cocaine and fentanyl self-administration in rats.

The influence of cardiac output on propofol and fentanyl pharmacokinetics and pharmacodynamics in patients undergoing abdominal aortic surgery

Cardiac output (CO) is expected to affect elimination and distribution of highly extracted and perfusion rate-limited drugs. This work was undertaken to quantify the effect of CO measured by the pulse pressure method on pharmacokinetics and pharmacodynamics of propofol and fentanyl administrated during total intravenous anesthesia (TIVA). The data were obtained from 22 ASA III patients undergoing abdominal aortic surgery. Propofol was administered via target-controlled infusion system (Diprifusor) and fentanyl was administered at a dose of 2-3 µg/kg each time analgesia appeared to be inadequate. Hemodynamic measurements as well as bispectral index were monitored and recorded throughout the surgery. Data analysis was performed by using a non-linear mixed-effect population modeling (NONMEM 7.4 software). Three compartment models that incorporated blood flows as parameters were used to describe propofol and fentanyl pharmacokinetics. The delay of the anesthetic effect, with respect to plasma concentrations, was described using a biophase (effect) compartment. The bispectral index was linked to the propofol and fentanyl effect site concentrations through a synergistic Emax model. An empirical linear model was used to describe CO changes observed during the surgery. Cardiac output was identified as an important predictor of propofol and fentanyl pharmacokinetics. Consequently, it affected the depth of anesthesia and the recovery time after propofol-fentanyl TIVA infusion cessation. The model predicted (not observed) CO values correlated best with measured responses. Patients' age was identified as a covariate affecting the rate of CO changes during the anesthesia leading to age-related difference in individual patient's responses to both drugs.

Pain management in patients with chronic kidney disease and end-stage kidney disease

PURPOSE OF REVIEW

This review evaluates current recommendations for pain management in chronic kidney disease (CKD) and end-stage kidney disease (ESKD) with a specific focus on evidence for opioid analgesia, including the partial agonist, buprenorphine.

RECENT FINDINGS

Recent evidence supports the use of physical activity and other nonpharmacologic therapies, either alone or with pharmacological therapies, for pain management. Nonopioid analgesics, including acetaminophen, topical analgesics, gabapentinoids, serotonin-norepinephrine reuptake inhibitors, and TCA may be considered based on pain cause and type, with careful dose considerations in kidney disease. NSAIDs may be used in CKD and ESKD for short durations with careful monitoring. Opioid use should be minimized and reserved for patients who have failed other therapies. Opioids have been associated with increased adverse events in this population, and thus should be used cautiously after risk/benefit discussion with the patient. Opioids that are safer to use in kidney disease include oxycodone, hydromorphone, fentanyl, methadone, and buprenorphine. Buprenorphine appears to be a promising and safer option due to its partial agonism at the mu opioid receptor.

SUMMARY

Pain is poorly managed in patients with kidney disease. Nonpharmacological and nonopioid analgesics should be first-line approaches for pain management. Opioid use should be minimized with careful monitoring and dose adjustment.

Anticipatory prescribing in community end-of-life care in the UK and Ireland during the COVID-19 pandemic: online survey

BACKGROUND

Anticipatory prescribing (AP) of injectable medications in advance of clinical need is established practice in community end-of-life care. Changes to prescribing guidelines and practice have been reported during the COVID-19 pandemic.

AIMS AND OBJECTIVES

To investigate UK and Ireland clinicians' experiences concerning changes in AP during the COVID-19 pandemic and their recommendations for change.

METHODS

Online survey of participants at previous AP national workshops, members of the Association for Palliative Medicine of Great Britain and Ireland and other professional organisations, with snowball sampling.

RESULTS

Two hundred and sixty-one replies were received between 9 and 19 April 2020 from clinicians in community, hospice and hospital settings across all areas of the UK and Ireland. Changes to AP local guidance and practice were reported: route of administration (47%), drugs prescribed (38%), total quantities prescribed (35%), doses and ranges (29%). Concerns over shortages of nurses and doctors to administer subcutaneous injections led 37% to consider drug administration by family or social caregivers, often by buccal, sublingual and transdermal routes. Clinical contact and patient assessment were more often remote via telephone or video (63%). Recommendations for regulatory changes to permit drug repurposing and easier community access were made.

CONCLUSIONS

The challenges of the COVID-19 pandemic for UK community palliative care has stimulated rapid innovation in AP. The extent to which these are implemented and their clinical efficacy need further examination.

Postoperative Single-shot Epidural Fentanyl and Bupivacaine for Postoperative Analgesia After Lumbar Decompression: A Prospective, Double-blind Randomized Study

STUDY DESIGN

Randomized clinical trial.

OBJECTIVE

To evaluate the efficacy of the postoperative single-shot bolus of epidural Fentanyl and Bupivicaine in providing pain relief postlumbar decompression surgery.

SUMMARY OF BACKGROUND DATA

Despite lumbar decompression's success in alleviating symptoms of sciatica, radiculopathy, and neurogenic claudication, transient back and buttock pain has been a common complaint postoperatively. Providing good postoperative pain alleviation predicts patient's quality of recovery.

METHODS

We performed a randomized, double-blinded, clinical trial. Forty-five patients scheduled for lumbar decompression for a year's period who were randomly assigned to receive a postoperative bolus of 10-mL solution of 50 mcg of Fentanyl, 0.125% Bupivacaine, and 0.9% saline solution via an intraoperatively placed epidural catheter immediately after wound closure, before dressing application. Facial pain scale scores (from 0 to 10) were measured at three time points after surgery (fully awake at recovery room, transfer to ward, first postoperative day). Postoperative need for oral analgesics, time to independent ambulation, associated adverse events, and time to hospital discharge were also evaluated.

RESULTS

Pain scores were noted to be significantly lower at all time points in the epidural group (P < 0.001). In turn, they also received less on-demand oral pain medications than those in the control group (P = 0.000). The mean time to ambulation was 0.09 days in the epidural group and 0.91 days in the decompression-alone group (P = 0.000). Criteria for hospital discharge were usually met on Day 0 in the epidural and Day 1 in the control group (P = 0.000). Within the study period, only one infection was noted in the epidural group which necessitated additional lumbar spine surgery (4.3%). No adverse events or complications related to Fentanyl use were observed.

CONCLUSIONS

A postoperative bolus of Fentanyl and Bupivacaine is effective in reducing early postoperative pain without the related complications of opiod administration.

LEVEL OF EVIDENCE

2.

Blunted endogenous opioid release following an oral dexamphetamine challenge in abstinent alcohol-dependent individuals

Addiction has been proposed as a 'reward deficient' state, which is compensated for with substance use. There is growing evidence of dysregulation in the opioid system, which plays a key role in reward, underpinning addiction. Low levels of endogenous opioids are implicated in vulnerability for developing alcohol dependence (AD) and high mu-opioid receptor (MOR) availability in early abstinence is associated with greater craving. This high MOR availability is proposed to be the target of opioid antagonist medication to prevent relapse. However, changes in endogenous opioid tone in AD are poorly characterised and are important to understand as opioid antagonists do not help everyone with AD. We used [11C]carfentanil, a selective MOR agonist positron emission tomography (PET) radioligand, to investigate endogenous opioid tone in AD for the first time. We recruited 13 abstinent male AD and 15 control participants who underwent two [11C]carfentanil PET scans, one before and one 3 h following a 0.5 mg/kg oral dose of dexamphetamine to measure baseline MOR availability and endogenous opioid release. We found significantly blunted dexamphetamine-induced opioid release in 5 out of 10 regions-of-interest including insula, frontal lobe and putamen in AD compared with controls, but no significantly higher MOR availability AD participants compared with HC in any region. This study is comparable to our previous results of blunted dexamphetamine-induced opioid release in gambling disorder, suggesting that this dysregulation in opioid tone is common to both behavioural and substance addictions.

Spinal anesthesia for cesarean section in a super morbidly obese parturient: A case report

INTRODUCTION

The population of obese individuals is increasing worldwide, and as a result, the number of mothers with super morbid obesity undergoing cesarean sections is also increasing. However, little is known about which anesthetic technique is appropriate for cesarean sections of super morbidly obese parturients.

PATIENT CONCERNS

A 35-year-old woman with body mass index 61.3 kg/m at a gestational age of 37 weeks.

DIAGNOSIS

The patient was super morbidly obese parturient.

INTERVENTIONS

Spinal anesthesia was performed. A spinal needle was inserted into the L4-5 interspinous space in the sitting position. After confirmation of cerebrospinal fluid, 0.5% hyperbaric bupivacaine 9 mg and fentanyl 20 μg were injected into the subarachnoid space.

OUTCOMES

After the administration of spinal anesthetics, the nerve block to the T8 dermatome level was confirmed, surgery was performed, and the fetus was delivered. The patient's vital signs were stable until the end of the operation.

CONCLUSION

There is no established strategy for selecting a method of anesthesia in patients with morbid obesity (body mass index 40 kg/m or more). For this reason and considering the amount of bupivacaine used for spinal anesthesia, we wanted to share our experience with spinal anesthesia for cesarean section in a super morbidly obese parturients.

Association between intraoperative and postoperative epidural or intravenous patient-controlled analgesia and pancreatic fistula after distal pancreatectomy

PURPOSE

This study aimed to elucidate the association between postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP) and clinicopathological factors and intraoperative and postoperative epidural or intravenous patient-controlled analgesia (IV-PCA).

METHODS

We reviewed data of 116 patients who underwent distal pancreatectomy at Gunma University Hospital from October 2000 to October 2019. Clinical POPF was defined as the International Study Group of Pancreatic Fistula grade B or C.

RESULTS

Intraoperative and postoperative analgesia included fentanyl-mediated IV-PCA (n = 37, 32%), fentanyl-mediated epidural analgesia (n = 39, 34%), and morphine-mediated epidural analgesia (n = 40, 34%). All patients had received analgesia. Clinical POPF occurred in 34 of the 116 (29%) DP cases. Male sex (P = 0.035) and the length of operation time (P = 0.0070) were significant risk factors of clinical POPF. Furthermore, a thick pancreas was more likely to cause clinical POPF than a thin one (P = 0.052). No statistically significant difference was found between other factors, including intraoperative and postoperative analgesia (P = 0.95), total median oral morphine equivalents (P = 0.23), and clinical POPF.

CONCLUSION

Intraoperative and postoperative epidural analgesia and IV-PCA are not associated with clinical POPF after DP. Our results suggest that morphine and fentanyl can be used as IV-PCA or epidural analgesia.

[Comparison of hospital consumption of immediate-release fentanyl: use or abuse?]

OBJECTIVE

Immediate-release fentanyl is indicated in the treatment of breakthrough pain in cancer patients who already receive opioids as background chronic analgesia. According to an alert issued by the Spanish Agency of Medicines, its consumption under non-authorized conditions has alarmingly increased in recent years, with a greater risk of abuse and dependence. The main objective of this study is to compare the off-label use of immediate-release fentanyl in our hospital during 2014 and 2017.

METHODS

Retrospective cross-sectional descriptive study in which immediate-release fentanyl prescriptions were compared in adult patients admitted during 2014 and 2017 in a group 5 hospital. Variables were collected by the electronic medical record. The association study between qualitative variables was calculated using the χ² test, and quantitative variables with the t-student test.

RESULTS

In 2014, 0.43 immediate-release fentanyl prescriptions were made in our center for every 100 admissions, and in 2017 0.54/100 admissions. 22.1% (n=34) prescriptions were off-label in 2014, while in 2017 31.8% (n=76) (p=0.034). Both years, the most frequent off-label indications were healing of ulcers and wounds and non-cancer chronic pain.

CONCLUSIONS

The use of immediate-release fentanyl in the hospital setting has considerably increased in comparison to 2014, as well as its off-label use.

Opioid rotation from transdermal fentanyl to continuous subcutaneous hydromorphone in a cachectic patient: A case report and review of the literature

Opioid rotation from transdermal fentanyl to an alternate opioid is often necessitated in advanced disease, but is fraught with uncertainty due to variable absorption from the patch in end-stage illness and the lack of a clearly established opioid rotation ratio. The manufacturer of transdermal fentanyl provides opioid rotation recommendations only for rotation from the oral morphine equivalent daily dose (MEDD) of opioid to the patch, not in the opposite direction. This is a case report of a single patient with cancer and cachexia admitted to the palliative care unit of a large academic medical centre in Canada. The patient is a 50-year-old female with widely metastatic breast cancer who developed opioid toxicity when maintenance transdermal fentanyl patch therapy (100 μg patch applied every 72 h) was rotated to subcutaneous hydromorphone infusion to improve pain control. Hydromorphone was initiated at a rate of 1 mg/h by continuous infusion based on an opioid rotation ratio for transdermal fentanyl (μg/h):MEDD (mg/day) of 1:2.4. Opioid toxicity eventually resolved with downward titration of hydromorphone to only 30% of the initially estimated equianalgesic dose. This case highlights the need for close follow-up of all patients undergoing opioid rotation from transdermal fentanyl and reinforces the need to reduce the initial dose of the new opioid by 30%-50% of the calculated MEDD, especially when rotating from a high dose of transdermal fentanyl, or if there are factors potentially impairing absorption from the patch such as age, cachexia and weight loss, or if rotation is performed for reasons other than uncontrolled pain.

The Haemodynamic Response to Endotracheal Intubation at Different Time of Fentanyl Given During Induction: A Randomised Controlled Trial

Endotracheal intubation elicits huge spectrum of stress responses which are hazardous in high-risk patients. Numerous drugs and techniques have been applied to attenuate the stress responses. In this double-blind study, one hundred and forty-five patients over 20 years old, ASA physical status I and II, undergoing elective surgeries requiring general anaesthesia with endotracheal intubation were included. Patients were randomly divided into three groups which fentanyl 2 mcg/kg was given at either 1, 2, 3 minutes before intubation. All groups received midazolam 0.05 mg/kg, lidocaine 0.5 mg/kg, propofol 2 mg/kg and rocuronium 1 mg/kg before intubation. Haemodynamic parameters were recorded for 10 minutes after induction. Two-level longitudinal hierarchical linear models were used for data interpretation and P < 0.05 was considered statistically significant. The study demonstrated significantly lower haemodynamic responses in the group who received fentanyl 2 minutes before intubation (P < 0.05). Confounding factors such as smoking, hypertension, diabetes mellitus and preoperative intravenous fluid supplement were analysed. In conclusion, fentanyl injection 2 minutes before intubation is recommended in order to obtain the most stable haemodynamic status.

Comparison of ropivacaine with ropivacaine and fentanyl in continuous epidural analgesia for postherpetic neuralgia: A STROBE-compliant retrospective study

Continuous epidural analgesia (CEA) using local anesthetics is frequently used to control herpes zoster pain and prevent postherpetic neuralgia (PHN). However, few studies have been conducted to determine the efficacy of epidural drugs administered as CEA to manage PHN. This retrospective study was designed to evaluate the effectiveness of CEA with ropivacaine alone or with ropivacaine and fentanyl for controlling pain caused by PHN.We reviewed the medical records of 71 patients. We studied 2 groups: epidural ropivacaine (ER; CEA with ropivacaine alone; n = 44) and epidural ropivacaine and fentanyl (Epidural ropivacaine and fentanyl (ERF); CEA with ropivacaine and fentanyl; n = 27). To evaluate pain, a numeric rating scale (NRS) was evaluated at 6 time points: immediately before the procedure (baseline NRS score); 1 hour after the procedure; 14 days after the procedure; and 1, 3, and 6 months after the procedure. Complication rates were recorded during CEA. We also investigated whether additional invasive procedures were needed due to insufficient pain control during the 6-month follow-up period.After adjusting for confounding variables, there were no significant differences in the NRS scores between the 2 groups at any time point. The adjusted odds ratio for additional invasive procedures within 6 months after CEA was 1.03-times higher in the ERF group than in the ER group, but this difference was not statistically significant (95% confidence interval: 0.33-3.23, P = .96). Rates of complication (dysuria, vomiting, nausea, itching sensation, and hypotension) during CEA were higher in the ERF group than in the ER group. However, the differences were not statistically significant.There was no difference in the management of pain in patients with PHN between the groups. Epidural administration of fentanyl with ropivacaine did not improve pain management when compared to ropivacaine alone. Although not statistically significant, the incidence of complications during CEA was higher in the opioid combination group.

Comparison of the effects of morphine-lidocaine-ketamine and fentanyl-lidocaine-ketamine combinations administered as constant rate infusions on postprocedure rectal temperature in dogs

OBJECTIVE

To compare the effects of morphine-lidocaine-ketamine (MLK) and fentanyl-lidocaine-ketamine (FLK) combinations administered as constant rate infusions (CRIs) during and after veterinary procedures on postprocedure rectal temperature in dogs.

ANIMALS

32 clinically normal client-owned dogs undergoing nonemergent procedures.

PROCEDURES

Dogs were randomly assigned to receive an MLK or FLK combination (16 dogs/group). During the procedure, each dog received 2% lidocaine hydrochloride (1 mg/kg/h; both groups), ketamine hydrochloride (0.6 mg/kg/h; both groups), and morphine (0.36 mg/kg/h; MLK group) or fentanyl (4 μg/kg/h; FLK group) via CRI for analgesia; esophageal temperature was maintained at 37° to 39°C. At extubation, each drug dose in each assigned combination was halved and administered (via CRI) for 12 additional hours for postprocedure analgesia. Rectal temperature and other data were recorded at baseline (prior to administration of premedicants), extubation (0 hours), and 0.5, 1.5, 3, 6, and 12 hours thereafter.

RESULTS

Mean postprocedure rectal temperature was significantly lower at each postextubation time point for the MLK group, compared with corresponding values for the FLK group. Compared with the baseline value, mean postprocedure rectal temperature was significantly lower at 0, 0.5, 1.5, and 3 hours for the FLK group and at all postprocedure time points for the MLK group. Hypothermia (rectal temperature < 37°C) was detected at ≥ 1 postprocedure time point more often in dogs in the MLK group (9/16) than in the FLK group (1/16).

CONCLUSIONS AND CLINICAL RELEVANCE

Dogs that received an MLK combination for analgesia during and after a veterinary procedure developed hypothermia more commonly than did dogs that received an FLK combination under similar conditions.

Analgesia for spinal anesthesia positioning in elderly patients with proximal femoral fractures: Dexmedetomidine-ketamine versus dexmedetomidine-fentanyl

Elderly patients with femoral fractures are anticipated to endure the most pain caused by positional changes required for spinal anesthesia. To improve pain relief, we compared the analgesic effects of intravenous dexmedetomidine-ketamine and dexmedetomidine-fentanyl combinations to facilitate patient positioning for spinal anesthesia in elderly patients with proximal femoral fractures. Forty-six patients were randomly assigned to two groups and received either 1 mg/kg of intravenous ketamine (group K) or 1 μg/kg of intravenous fentanyl (group F) concomitant with a loading dose of dexmedetomidine 1 μg/kg over 10 minutes, then dexmedetomidine infusion only was continued at 0.6 μg/kg/h for following 20 minutes, and titrated at a rate of 0.2 to 0.6 μg/kg/h until the end of surgery. After completion of the infusion of either ketamine or fentanyl, the patients were placed in the lateral position with the fracture site up. The pain score (0 = calm, 1 = facial grimacing, 2 = moaning, 3 = screaming, and 4 = unable to proceed because of restlessness or agitation) was used to describe the pain intensity in each step during the procedure (lateral positioning, hip flexion, and lumbar puncture), and quality score (0 = poor hip flexion, 1 = satisfactory hip flexion, 2 = good hip flexion, and 3 = optimal hip flexion) was used to describe the quality of posture. Group K showed a median pain score of 0 (0-1), 0 (0-0) and 0 (0-0) in lateral positioning, hip flexion and lumbar puncture, respectively, while group F showed a score of 3 (2.75-3), 3 (2-3) and 0 (0-1), respectively. The pain score in lateral positioning (P < .0001) and hip flexion (P < .0001) was significantly lower in group K than group F. Group K showed the significantly higher quality scores of spinal anesthesia positioning (P = .0044) than group F. Hemodynamic adverse effects, such as bradycardia, hypotension, and desaturation, were not significantly different between the groups. The administration of dexmedetomidine-ketamine showed a greater advantage in reducing pain intensity and increasing the quality with patient positioning during spinal anesthesia in elderly patients with proximal femoral fractures, without any serious adverse effects.

The Effectiveness of Low-dose Dexmedetomidine Infusion in Sedative Flexible Bronchoscopy: A Retrospective Analysis

Background and objectives: Flexible bronchoscopy has been widely used for diagnosis and intervention, while various drugs are used for sedation during bronchoscopy. We examined two regular standardized sedation options (with or without dexmedetomidine) regularly used in our regional hospital. The aim was to assess the efficacy and safety of dexmedetomidine on conscious sedation under bronchoscopy. Materials and Methods: A retrospective chart review was conducted from April 2017 to March 2018. All patients undergoing flexible bronchoscopy with moderate sedation were enrolled. Patients having received dexmedetomidine-propofol-fentanyl were defined as group D, and those having received midazolam-propofol-fentanyl were defined as group M. The primary outcome was a safety profile during the procedure, including the incidence of procedural interference by patient cough or movement, transient hypoxemia, and hypotension. The secondary outcome was measured by the recovery profile (awake and ambulation time). Results: Thirty-five patients in group D and thirty-three in group M were collected in this retrospective study. All patients underwent the procedure successfully. Group D showed higher safety with fewer procedural interference incidences by cough or body movement than Group M (3.3% versus 36.3%, p < 0.001) and minor respiratory adverse effects. Patients in group D showed faster recovery in a shorter ambulation time than group M (24.9 ± 9.7 versus 31.5 ± 11.9, p = 0.02). In group D, bronchoscopist satisfaction to sedation was higher than group M (p = 0.01). More transient bradycardia episodes were noted in patients receiving dexmedetomidine (p < 0.05), but all recovered without atropine intervention. Overall post-procedural adverse events and satisfaction were comparable in the two groups. Conclusions: The co-administration of dexmedetomidine met the safety and recovery demands of flexible bronchoscopy. Compared to the conventional midazolam-propofol-fentanyl regimen, the application of dexmedetomidine improved sedative effectiveness with less procedural interruptions, shorter time to ambulation and higher bronchoscopist satisfaction.

Iatrogenic Opioid Withdrawal Syndrome in Critically Ill Patients: a Retrospective Cohort Study

BACKGROUND

Opioid withdrawal syndrome (OWS) may occur following the reduction or discontinuation of opioid analgesics. In critically ill pediatric patients, OWS is a common and clinically significant condition. However, OWS in adult patients has not been assessed in detail. Therefore, we aimed to investigate the incidence, risk factors, and clinical features of OWS in mechanically ventilated patients treated in an adult intensive care unit (ICU).

METHODS

This study was a retrospective evaluation of data from patients treated in the medical ICU for > 3 days and who received only one type of opioid analgesic. OWS was assessed over a 24 hours period from discontinuation or reduction (by > 50%) of continuous opioid infusion. OWS was defined as the presence of ≥ 3 central nervous system or autonomic nervous system symptoms.

RESULTS

In 126 patients treated with remifentanil (n = 58), fentanyl (n = 47), or morphine (n = 21), OWS was seen in 31.0%, 36.2%, and 9.5% of patients, respectively (P = 0.078). The most common symptom was a change in respiratory rate (remifentanil, 94.4%; fentanyl, 76.5%; morphine, 100%). Multivariate Cox-proportional hazards model showed that OWS was negatively associated with morphine treatment (hazard ratio [HR], 0.17; 95% confidence interval [CI], 0.037-0.743) and duration of opioid infusion (HR, 0.566; 95% CI, 0.451-0.712).

CONCLUSION

OWS is not uncommon in mechanically ventilated adult patients who received continuous infusion of opioids for > 3 days. The use of morphine may be associated with a decreased risk of OWS.

Sedation During Endoscopy in Patients with Cirrhosis: Safety and Predictors of Adverse Events

BACKGROUND

Sedation during endoscopy in cirrhotic patients is typically via moderate sedation, most commonly using a combination of a benzodiazepine (i.e., midazolam) and narcotic (i.e., fentanyl) or with propofol using monitored anesthesia care (MAC). Here, we examined the safety of moderate sedation and MAC in patients with cirrhosis.

METHODS

This retrospective cohort study of cirrhotic patients undergoing endoscopy from a large academic medical center between 2010 and 2014 examined extensive clinical data including the following: past history, physical findings, laboratory results, and procedural adverse events. Adverse events were defined a priori and included hypoxia, hypotension, bleeding, and death.

RESULTS

We identified 2618 patients with cirrhosis who underwent endoscopic procedures; the mean age was 56 years, 36% were female, the mean Child-Pugh score was 9.3 (IQR: 8, 11), and Charlson Comorbidity Index score was 3.2 (IQR: 1, 4); 1157 had MAC; and 1461 had moderate sedation. There was no difference in the frequency of adverse events in MAC and moderate sedation groups, with a total of 15 adverse events (7/1157 MAC and 8/1461 moderate sedation). The most common procedure performed was esophagogastroduodenoscopy (EGD, n = 1667) and was associated with 10 adverse events. Overall, adverse events included bradycardia (1), hypoxia (7), bleeding (5), laryngospasm (1), and perforation (1). The frequency was similar for EGD, ERCP, and colonoscopy-each at a rate of 0.6%.

CONCLUSIONS

Adverse events in cirrhotic patients undergoing endoscopy appeared to be similar with moderate sedation or MAC, and the frequency was the same for different types of procedures.

(Re)shaping the self: An ethnographic study of the embodied and spatial practices of women who use drugs

While gendered experiences of drug use have been well-established, understanding how women resist structures that constrain their agency is important for mitigating drug-related harms, especially as overdose has become North America's leading cause of accidental death. Drawing on the intersectional risk environments of WWUD, this ethnographic study examined how gendered expectations of women's drug use, appearance, and comportment influenced vulnerability to overdose within the context of a fentanyl-driven overdose crisis. This community-engaged ethnography, conducted in Vancouver, Canada from May 2017 to December 2018, included in-depth interviews with 35 marginally-housed WWUD (transgender-inclusive) and approximately 100 h of fieldwork in single room accommodation (SRA) housing and an established street-based drug scene. Data were analyzed thematically with attention to embodiment, agency, and intersectionality. Findings highlight how gendered expectations and normative violence impacted women's use of space, both in the drug scene and SRAs. To resist efforts to 'discipline' their bodies, participants engaged in situated gender performances. Physical appearance was also deemed critical to managing drug use disclosure. Participants adopted gendered embodied practices, including altered consumption methods or injecting in less visible areas, to conceal their use from peers and at times, their partners. To resist harms associated with involuntary disclosure, participants often used alone in SRAs or in public spaces. While such practices allowed women to exert agency within constraining systems, they concurrently heightened overdose risk. Findings demonstrate how women engaged in everyday acts of resistance through embodied drug use practices, which increased their agency but elevated overdose risk. Implementing gender-specific programs that increase bodily agency and control (e.g. low-threshold services for personal care, women-focused harm reduction support) are needed to reduce risk of overdose for WWUD.

Effect of intraoperative Hartmann's versus hypotonic solution administration on FLACC pain scale scores in children: A prospective randomized controlled trial

Background

In healthy children, an isotonic solution containing no glucose or a small amount of glucose (1–2%) has been recommended as an intraoperative maintenance fluid due to the potential risk of hyponatremia associated with hypotonic solutions. However, a hypotonic solution with glucose is still widely used as a maintenance fluid for pediatric anesthesia. We speculated that the hypotonic solution may worsen postoperative discomfort and irritability in pediatric patients due to hyponatremia.

Patients and methods

In the current study, we compared the post-operative Face, Legs, Activity, Cry, Consolability(FLACC) scale scores of pediatric patients aged 3–10 years who received either a 1:2 dextrose solution or Hartmann's solution during Nuss Bar removal.

Results

The FLACC scale score in the post-anesthesia care unit was higher in the 1:2 dextrose solution group(HYPO) (n = 20) than in the Hartmann’s solution group(ISO) (n = 20) (6.30 vs 4.70, p = 0.044, mean difference and 95% Confidence Interval(CI) was 1.6 (0.04 to 3.16)). We also compared opioid consumption at the post-anesthesia care unit. Total dose of fentanyl per body weight in the post-anesthesia care unit was also higher in the HYPO (0.59 vs 0.37 mcg/kg, p = 0.042, mean difference and 95% CI was 0.22 mcg/kg (0.030 to 0.402)).

Conclusions

Intraoperative use of the hypotonic solution in children causes increased FLACC scale scores, leading to higher opioid consumption in post-anesthesia care unit.

Evaluation of Renal Function at 24, 48, and 72 Hours and 3 Months After Transplant: Comparison of 3 Anesthetic Techniques

BACKGROUND

General anesthesia is the conventional management of renal transplant, and its evolution has revolved around the development of new drugs; however, a group of patients meet conditions for neuraxial anesthesia, because of their comorbidities, who are at greater risk of complications with general anesthesia and are not favorable to grafting.

METHODS

We conducted a controlled clinical trial of 109 renal transplant recipients where renal function was evaluated at 24, 48, and 72 hours and 3 months after transplant, and we compared regional, general anesthesia with inhaled anesthetic and total intravenous anesthesia. It was performed for 1 year, and serum creatinine, urea nitrogen, and electrolytes were evaluated. During the intraoperative period central venous pressure, mean arterial pressure, vasopressors, fluid therapy, diuretics, surgical time, anesthesia, hot and cold ischemia, immunosuppressants, and antihypertensives were evaluated. They were analyzed with χ² independence and 1-way and 2-way repeated measures.

RESULTS

The type of anesthesia was associated with hemodynamic stability (P = .018), the use of vasopressor (P = .005), and fluid therapy (P = .011). A value of P = .005 was found for central venous pressure at discharge from the operating room, and preincisional mean arterial pressure (P = .015) was among the types of anesthesia. Creatinine, blood urea nitrogen, sodium, and potassium were statistically significant over time (P < .001) but showed no difference between types of anesthesia.

CONCLUSION

There is no difference between anesthetic techniques and clinical results over time. The personalized anesthetic technique will improve the neuroendocrine response and surgical stress, decrease the need for vasopressors and analgesics, and reduce complications.

Creation of a score to predict risk of high conscious sedation requirements in patients undergoing endoscopy

BACKGROUND AND AIMS

The administration of intravenous conscious sedation to patients undergoing GI endoscopy carries a risk of cardiopulmonary adverse events. Our study aim was to create a score that stratifies the risk of occurrence of either high-dose conscious sedation requirements or a failed procedure.

METHODS

Patients receiving endoscopy via endoscopist-directed conscious sedation were included. The primary outcome was occurrence of sedation failure, which was defined as one of the following: (1) high-dose sedation, (2) the need for benzodiazepine/narcotic reversal agents, (3) nurse-documented poor patient tolerance to the procedure, or (4) aborted procedure. High-dose sedation was defined as >10 mg of midazolam and/or >200 μg of fentanyl or the meperidine equivalent. Patients with sedation failure (n = 488) were matched to controls (n = 976) without a sedation failure by endoscopist and endoscopy date.

RESULTS

Significant associations with sedation failure were identified for age, sex, nonclonazepam benzodiazepine use, opioid use, and procedure type (EGD, colonoscopy, or both). Based on these 5 variables, we created the high conscious sedation requirements (HCSR) score, which predicted the risk of sedation failure with an area under the curve of 0.70. Compared with the patients with a risk score of 0, risk of a sedation failure was highest for patients with a score ≥3.5 (odds ratio, 17.31; P = 2 × 10^-14). Estimated area under the curve of the HCSR score was 0.68 (95% confidence interval, 0.63-0.72) in a validation series of 250 cases and 250 controls.

CONCLUSIONS

The HCSR risk score, based on 5 key patient and procedure characteristics, can function as a useful tool for physicians when discussing sedation options with patients before endoscopy.

Leveraging crowdsourcing methods to collect qualitative data in addiction science: Narratives of non-medical prescription opioid, heroin, and fentanyl use

BACKGROUND

Online crowdsourcing methods have proved useful for studies of diverse designs in the behavioral and addiction sciences. The remote and online setting of crowdsourcing research may provide easier access to unique participant populations and improved comfort for these participants in sharing sensitive health or behavioral information. To date, few studies have evaluated the use of qualitative research methods on crowdsourcing platforms and even fewer have evaluated the quality of data gathered. The purpose of the present analysis was to document the feasibility and validity of using crowdsourcing techniques for collecting qualitative data among people who use drugs.

METHODS

Participants (N = 60) with a history of non-medical prescription opioid use with transition to heroin or fentanyl use were recruited using Amazon Mechanical Turk (mTurk). A battery of qualitative questions was included indexing beliefs and behaviors surrounding opioid use, transition pathways to heroin and/or fentanyl use, and drug-related contacts with structural institutions (e.g., health care, criminal justice).

RESULTS

Qualitative data recruitment was feasible as evidenced by the rapid sampling of a relatively large number of participants from diverse geographic regions. Computerized text analysis indicated high ratings of authenticity for the provided narratives. These authenticity percentiles were higher than the average of general normative writing samples as well as than those collected in experimental settings.

CONCLUSIONS

These findings support the feasibility and quality of qualitative data collected in online settings, broadly, and crowdsourced settings, specifically. Future work among people who use drugs may leverage crowdsourcing methods and the access to hard-to-sample populations to complement existing studies in the human laboratory and clinic as well as those using other digital technology methods.