Closed-loop wearable naloxone injector system.

Overdoses from non-medical use of opioids can lead to hypoxemic/hypercarbic respiratory failure, cardiac arrest, and death when left untreated. Opioid toxicity is readily reversed with naloxone, a competitive antagonist that can restore respiration. However, there remains a critical need for technologies to administer naloxone in the event of unwitnessed overdose events. We report a closed-loop wearable injector system that measures respiration and apneic motion associated with an opioid overdose event using a pair of on-body accelerometers, and administers naloxone subcutaneously upon detection of an apnea. Our proof-of-concept system has been evaluated in two environments: (i) an approved supervised injection facility (SIF) where people self-inject opioids under medical supervision and (ii) a hospital environment where we simulate opioid-induced apneas in healthy participants. In the SIF (n = 25), our system identified breathing rate and post-injection respiratory depression accurately when compared to a respiratory belt. In the hospital, our algorithm identified simulated apneic events and successfully injected participants with 1.2 mg of naloxone. Naloxone delivery was verified by intravenous blood draw post-injection for all participants. A closed-loop naloxone injector system has the potential to complement existing evidence-based harm reduction strategies and, in the absence of bystanders, help make opioid toxicity events functionally witnessed and in turn more likely to be successfully resuscitated.

Elevated customary alcohol consumption attenuates opioid effects.

BACKGROUND: Regular alcohol consumption is on the rise among older adults and has the potential of altering the subjective experience of pain and response to pain medications. This study examined the cognitive, analgesic and side effect response to oxycodone in middle age and older adults with elevated levels of customary alcohol consumption in a human laboratory setting. METHODS: After refraining from alcohol for one day, eligible participants underwent baseline assessment cognition and side effects by means of questionnaires that were repeated at three time points (90 min, 5 and 8 h) following administration of a 10 mg oral dose of oxycodone. Response to pain stimulus (Cold Pressor Test (CPT)), pupil size, and plasma oxycodone were also measured. RESULTS: One hundred twenty-eight adults (age 35-85) completed the study day. Compared to those with lower customary alcohol consumption, participants with elevated alcohol consumption showed attenuated opioid-induced pupil constriction and cognitive decline on objective measures of working memory, sustained attention, inhibitory control, coordination on a simulated driving task, and subjective dysphoric effects with enhanced subjective euphoric effects. Oxycodone pharmacokinetics, pain tolerance to CPT, and Berg balance were impacted comparably between alcohol consumption groups. Women endorsed greater negative drug effects, whereas men endorsed positive drug effects. CONCLUSION: Independent of subject's age, elevated customary alcohol consumption attenuates opioid central effects (i.e., pupil miosis, impaired cognition) and gender influences subjective drug effects. Clinicians should consider alcohol consumption and gender when prescribing opioid medications.

Relationship of Phosphatidylethanol Biomarker to Self-Reported Alcohol Drinking Patterns in Older and Middle-Age Adults.

BACKGROUND: Risky alcohol consumption is on the rise among older adults. Biomarkers such as phosphatidylethanol (PEth) have been used to evaluate the correspondence between an objective, laboratory-based biomarker and self-report of alcohol consumption. This study examined the relationship between PEth, self-report of alcohol consumption, and health indices in a sample of community-dwelling older to middle-age adults (aged 35 to 89) with healthy and risky levels of alcohol consumption. METHODS: Self-reports of alcohol consumption were collected using the Alcohol Use Disorders Identification Test (AUDIT) and Form 30. In addition, indices of health along with a blood sample to determine PEth values were collected (N = 183). RESULTS: PEth was correlated with age, AUDIT-C, AUDIT total, alcohol consumption, mood, and liver function measures but not with medical comorbidity or body mass index (J Gerontol B Psychol Sci Soc Sci 73, 2018, 633). Alcohol consumption over the past 30 days measured with Form 30 was the strongest predictor of PEth levels for both middle-age and older adults, with age a small contributing predictor. General alcohol consumption patterns for amount of alcohol consumed over a 30-day period revealed middle-age adults consumed larger amounts of alcohol compared with older adults, but older adults consumed alcohol on more days than middle-age adults. Middle-age participants evidenced higher PEth levels than older adults at comparable drinking rates. CONCLUSIONS: Overall, findings suggest a strong relationship between alcohol consumption and PEth levels with age a small but contributing factor to predicting PEth levels.

Liability related to peripheral venous and arterial catheterization: a closed claims analysis.

BACKGROUND: Serious complications after peripheral IV and arterial vascular cannulations have been reported. To assess liability associated with these peripheral vascular catheters for anesthesiologists, we reviewed claims in the American Society of Anesthesiologists Closed Claims database. METHODS: Claims related to peripheral vascular catheterization were categorized as related to IV or arterial catheters. Complications related to IV catheters were categorized as to type of complication. Patient and case characteristics, severity of injury, and payments were compared between claims related to IV catheters and all other (nonperipheral catheter) claims in the database. Payment amounts were adjusted to 2007-dollar amounts using the consumer price index. RESULTS: Claims related to peripheral vascular catheterization accounted for 2% of claims in the database (n = 140 of 6894 claims), most (91%) associated with IV catheters (n = 127). The most common complications were skin slough (28%), swelling/infection (17%), nerve damage (17%), fasciotomy scars (16%), and air embolism (8%). Approximately half of these complications (55%) occurred after extravasation of drugs or fluids. Compared with other claims, IV claims involved a larger proportion of cardiac surgery (25% vs 2% for other, P < 0.001) and smaller proportion of emergency procedures (8% vs 22% for other, P < 0.001). Claims related to arterial catheters were few (n = 13, 8%), with only seven associated with radial artery catheterization. CONCLUSIONS: Claims related to IV catheters were an important source of liability for anesthesiologists, approximately half of which resulted from extravasation of drugs or fluid. Claims related to radial arterial catheterization were uncommon.