pupillometry opioids

BACKGROUND: Safe postoperative pain relief with opioids is an unmet critical medical need in children. There is a lack of objective, noninvasive bedside tool to assess central nervous system (CNS) effects of intraoperative opioids. Proactive identification of children at risk for postoperative respiratory depression (RD) will help tailor analgesic therapy and significantly improve the safety of opioids in children. Quantitative pupillometry (QP) is a noninvasive, objective, and real-time tool for monitoring CNS effect-time relationship of opioids...

The endogenous opioid system has been implicated during experiences of pleasure (i.e., from food or sex). Music can elicit intense emotional and bodily sensations of pleasure, called 'Chills'. We investigated the effects of an opioid antagonist (50 mg naltrexone) or placebo (40 μg d3-vitamin) while listening to self-selected music or other 'control' music selected by another participant. We used a novel technique of continuous measurement of pleasantness with an eye tracker system, where participants shifted their eyes along a visual analogue scale, in the semblance of a thermometer so that, as the music unfolded, gaze positions indicated the self-reported hedonic experience...

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...

BACKGROUND: High-dose opioids are conventionally used for cardiac anesthesia, but without monitoring of nociception. In non-cardiac surgical procedures the intra - operative dose of opioids can be individualized and reduced with pupillometric monitoring of the pupillary pain index (PPI; scale 1-9). A randomized controlled trial was carried out to explore whether pupillometry can be used for nociception monitoring in cardiac anesthesia and whether it leads to opioid reduction. METHODS: A sample of 57 cardiac surgery patients receiving continuously administered sufentanil (initial dosage 0...

PURPOSE: Pupillometry is a technique for objective quantification of nociception that takes into account the central processing of noxious stimuli and its sympathetic response. This narrative review provides an overview of the physiology of the pupil, the principles of pupillometry, and its potential application in the perioperative environment, especially in nociception monitoring and quantifying responses to opioids. SOURCE: Relevant articles, including reports of original investigation, review articles, and meta-analyses were identified from searches of PubMed and Google Scholar databases...

PURPOSE: To evaluate whether pupillary abnormalities would correlate with the severity of encephalopathy in critically ill cirrhotic patients. METHODS: In this retrospective study, we enrolled adult cirrhotic patients admitted to the Intensive Care Unit undergoing automated pupillometry assessment within the first 72 h since ICU admission. Encephalopathy was assessed with West-Haven classification and Glasgow Coma Scale. Pupillometry-derived variables were also correlated with biological variables, including ammonium, renal function or inflammatory parameters, measured on the day of pupillary assessment...

INTRODUCTION/BACKGROUND: A rough, visual estimate of pupil size is used in grading the severity of opioid withdrawal. Few studies have examined the clinical utility of more precise automated pupillometry measurements. METHODS: This prospective cohort study enrolled 27 patients receiving opioid agonist therapy (OAT) to treat cravings or withdrawal during an acute hospitalization. Six sets of automated pupillometry measurements were obtained at regular intervals before and after administration of OAT...

BACKGROUND: Remifentanil is a commonly used opioid analgesic during anesthesia in children. Objective measurement of pain is required for adequate dosing of remifentanil. We investigated whether pupillometry-guided remifentanil administration can reduce intraoperative consumption of remifentanil in children. METHODS: We performed a single-blinded, prospective, randomized controlled trial from December 2018 through June 2019. Children who were 3-12 years of age and classified as having an American Society of Anesthesiologists physical status I-II and undergoing elective surgery under general anesthesia were included...

BACKGROUND: Intraoperative monitoring with pupillometry has shown promising results for nociception/antinociception balance monitoring. However, its benefits in clinical practice remain unproven. The aim of this study was to evaluate the efficacy of intraoperative pupillometry monitoring on intraoperative opioid consumption and postoperative pain compared to surgical pleth index (SPI), another widely investigated monitoring. METHODS: American Society of Anesthesiologists (ASA) I-II patients scheduled for elective laparoscopic cholecystectomy were included...

Pupillary reflex dilation (PRD) is triggered by noxious stimuli and diminished by opioid administration. In the postoperative period, PRD has been shown to be correlated with pain reporting and a useful tool to guide opioid administration. In this study we assessed whether pupillary measurements taken before extubation were related with the patient's reported pain in the Post-Anesthesia Care Unit (PACU) using the Numerical Rating Scale (NRS). Our objective was to evaluate the correlation of PRD and pupillary variables measured intraoperatively with postoperative pain under the same opioid concentration...

BACKGROUND: Intraoperative monitoring with pupillometry has shown promising results for nociception/antinociception balance monitoring. However, its benefits in clinical practice remain unproven. The aim of this study was to evaluate the efficacy of intraoperative pupillometry monitoring on intraoperative opioid consumption and postoperative pain compared to surgical pleth index (SPI), another widely investigated monitoring. METHODS: American Society of Anesthesiologists (ASA) I-II patients scheduled for elective laparoscopic cholecystectomy were included...

OBJECTIVE: To evaluate the human abuse potential, pharmacokinetics, pharmacodynamics, and safety of oral NKTR-181 (oxycodegol), a novel full mu-opioid receptor agonist, relative to oral oxycodone. DESIGN: This double-blind, randomized, single-dose, crossover human abuse potential study was conducted in healthy, adult, non-physically dependent recreational opioid users. SETTING: Inpatient clinical research site. SUBJECTS: Seventy-one subjects randomized (95...

BACKGROUND: Pupillometry monitoring under general anesthesia is based on the assumption that pupillary diameter variations reflect the adequacy of the provided analgesia to the intensity of the nociceptive surgical stimulus. The accurate interpretation of pupillometric data requires establishing clearly what the expected baseline unstimulated pupillary diameter at each specific level of hypnosis is. Opioids decrease pupillary diameter in a dose-dependent fashion. In contrast, the effects of hypnotic drugs on pupillary diameter are not well known...

Background Pupil size and reaction are influenced by opioids, an effect that is not considered to be affected by opioid tolerance. As clinicians have observed patients on high-dose opioids who exhibited seemingly normal pupil sizes, we wanted to dynamically assess the pupillary reflex in cancer patients on high-dose opioids. Methods We performed a dynamic assessment of the pupillary reflex in cancer patients on high-dose opioids and a control group of healthy volunteers using a portable, monocular, infrared pupillometer...

Pupillary examination has fundamental diagnostic and prognostic values in clinical practice. However, pupillary assessment was relied until present on manual, qualitative, examination, using manual flash penlights or lamps. Quantitative examination with the use of automated infrared video-pupillometers allows an objective assessment of several pupillary parameters and may be superior to manual subjective examination. The potential for quantitative pupillometry is multiple in the setting of critical care, for the monitoring and detection of secondary cerebral insults and to assess brainstem dysfunction and early coma outcome prognostication, and in the intra-operative anesthesiology setting, to assess analgesia and opioid requirement...

INTRODUCTION: Under-dosage or over-dosage of intraoperative analgesia can cause harm to patients. Many studies have demonstrated the clinical advantages of nociception monitoring tools, but with some conflicting results. To clarify the issue, this meta-analysis compared the effects of Analgesia Nociception Index (ANI), Surgical Pleth Index (SPI), and pupillometry monitoring methods with those of analgesia management practices of intraoperative opioid administration. EVIDENCE ACQUISITION: A comprehensive literature search was conducted to identify clinical trials that compared the effect of monitoring of nociception-antinociception balance (versus clinical signs) on intraoperative opioid administration...

OBJECTIVE: This study examined the nasal abuse deterrence of REMOXY ER, a novel high-viscosity extended-release oxycodone formulation. DESIGN: An Institutional Review Board-approved, single-center, randomized, double-blind, placebo, and active-controlled, four-way crossover study of intranasal REMOXY ER gel, manipulated or intact, and ground oxycodone immediate-release (IR). An open label extension examined pharmacokinetics of OxyContin® ER in the first 20 subjects...

BACKGROUND: Cebranopadol is a nociceptin/orphanin FQ peptide/opioid receptor agonist with central antinociceptive activity. We hypothesize that this novel mechanism of action may lead to a lower risk of abuse compared with pure μ-opioid peptide receptor agonists. METHODS: We conducted a single-dose, nested-randomized, double-blind crossover study in nondependent recreational opioid users to evaluate the abuse potential of single doses of cebranopadol relative to hydromorphone immediate release and placebo...

PURPOSE: Pharmacodynamic studies of naloxone require opioid agonism. Steady state condition may be achieved by remifentanil TCI (target controlled infusion). Opioid agonism can be measured by pupillometry. It is not known whether there are arteriovenous concentration differences for naloxone. The aim was thus to further develop a model for studying pharmacokinetic/pharmacodynamic aspects of naloxone and to explore whether a significant arteriovenous concentration difference for naloxone in humans was present...

BACKGROUND: Pupillary response by pupillary dilatation reflex (PDR) is a robust reflex, even measurable during general anaesthesia. However, the ability of infrared pupillometry to detect PDR differences obtained by intraoperative opioid administration in anaesthesized patients remains largely unknown. We analyzed the performance of automated infrared pupillometry in detecting differences in pupillary dilatation reflex response by a inbuilt standardized nociceptive stimulation program in patients under general anesthesia with a standardized propofol/fentanyl scheme...