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Introduction: In line with historical tobacco industry marketing claims, many consumers perceive cigarettes with filters as less harmful than cigarette without filters. However, scientific evidence indicates that cigarette filters do not reduce the risks associated with smoking. We examined opposition to banning the sale of cigarettes with filters, beliefs about whether removing filters makes cigarettes much more harmful, and whether this belief is associated with opposition to banning filters among adults who smoke cigarettes from four high-income countries., Methods: Data are from 2,980 adults who smoke cigarettes and participated in the 2022 ITC Smoking and Vaping Survey in Australia, Canada, England, and the United States (US). Weighted descriptives estimated opposition to a cigarette filter ban and the belief that removing filters makes cigarettes 'much more', 'a little more', 'not more' harmful, or 'don't know'. Adjusted regression analyses examined the association between opposition to banning filters (vs. support/don't know) and the belief that removing filters would make cigarettes much more harmful (vs. otherwise)., Results: Across all counties, 69.3% opposed banning filters, 11.5% of respondents supported banning filters, and 19.1% did not know (main effect for country differences: p=0.001). Country differences remained significant after adjusting for covariates (p=0.047), with adults who smoke in Australia and the US being significantly more likely to oppose a filter ban than those in England. Canada did not differ significantly from any of the countries. Nearly half (45.9%) believe that removing filters would make cigarettes much more harmful, 28.6% reported a little more harmful, 15.3% were unsure, and 10.2% reported not more harmful (country differences: p=0.002). Country differences were no longer significant after adjustment (p=0.18). Believing that removing filters makes cigarettes much more harmful was strongly associated with opposing a filter ban (78.5%) (vs. otherwise: 62.1%, p<0.001)., Conclusions: Across all four countries, three-quarters of adults who smoke erroneously believe that removing filters would make cigarettes more harmful, and believing that doing so would make cigarettes much more harmful was the strongest predictor of opposing a filter ban., Implications: More than 90% of manufactured cigarettes worldwide contain filters. Contrary to marketing claims by the tobacco industry, cigarette filters do not offer any health protection from cigarette smoke; however, three-quarters of adults who smoke erroneously believe that cigarettes with filters are much less harmful than cigarettes without filters. To protect public health and the environment, the World Health Organization has recommended that policymakers consider banning cigarette filters as they are unnecessary single use plastics., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.)

Introduction: The current study sought to examine trends in indicators of dependence for youth vaping and smoking during a period of rapid evolution in the e-cigarette market., Aims and Methods: Data are from repeat cross-sectional online surveys conducted between 2017 and 2022 among youth aged 16-19 in Canada, England, and the United States (US). Participants were 23 145 respondents who vaped and/or smoked in the past 30 days. Four dependence indicators were assessed for smoking and vaping (perceived addiction, frequent strong urges, time to first use after waking, days used in past month) and two for vaping only (use events per day, e-cigarette dependence scale). Regression models examined differences by survey wave and country, adjusting for sex, age, race, and exclusive/dual use., Results: All six indicators of dependence increased between 2017 and 2022 among youth who vaped in the past 30 days (p < .001 for all). For example, more youth reported strong urges to vape at least most days in 2022 than in 2017 (Canada: 26.5% to 53.4%; England: 25.5% to 45.4%; US: 31.6% to 50.3%). In 2017, indicators of vaping dependence were substantially lower than for smoking; however, by 2022, youth vaping was associated with a greater number of days used in the past month (Canada, US), shorter time to first use (all countries), and a higher likelihood of frequent strong urges (Canada, US) compared to youth smoking., Conclusions: From 2017 to 2022, indicators of vaping dependence increased substantially. By 2022, vaping dependence indices were comparable to those of smoking., Implications: Indicators of vaping dependence among youth have increased substantially since 2017 to levels that are comparable to cigarette dependence among youth who smoke. Future research should examine factors underlying the increase in dependence among youth who vape, including changes to the nicotine profile and design of e-cigarette products., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.)

Background and Aims: Vaping product packaging is varied and often features bright colours and novel designs, particularly among recently marketed disposable vapes. This study provides an overview of attributes found on the packaging of popular disposable vapes and e-liquid bottles in England, Canada and the United States (US) and assesses compliance with local packaging regulations., Design: Content analysis., Setting: Brick-and-mortar and online shops in England (London), Canada (Ontario) and the US (New Hampshire and South Carolina)., Cases: 108 vaping products (including packaging) from 76 brands in a range of flavours and nicotine levels. Specifically, 48 disposable vapes (15 from England, 16 from Canada, 17 from the US) and 60 e-liquid bottles (20 per country)., Measurements: Textual and graphic branding and marketing elements, independently coded by two researchers and checked by a third., Findings: Compliance with local packaging regulations varied across countries. Health warnings were present on the packaging of all but one nicotine-containing product, although 33% of disposables and 17% of e-liquids featuring the warning did not adhere to formatting requirements. Leaflets were seldom included with e-liquid bottles, even in England (45%) where mandatory, and omitted elsewhere. Labelling of nicotine type and batch numbers was inconsistent. Vaping product packaging featured claims relating to sensory perceptions (41%), most often flavours, and some (32%) featured youth-appealing content. Common graphic elements included stylised brand fonts (80%), brand logos (54%), product representations on the external packaging (47%) and abstract graphic elements (64%). Colours on packaging, disposable vapes and e-liquid bottles were associated with product flavour., Conclusions: In England, Canada and the United States, popular disposable vapes and e-liquid bottles appear to have varying compliance with local packaging regulations and inconsistent labelling of nicotine and product characteristics. The use of colourful designs, evocative descriptors and appealing graphics to promote flavours underscores the need for comprehensive packaging regulations and enforcement., (© 2024 The Author(s). Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.)

Introduction: This study examined menthol cigarette use among youth who smoked, after menthol cigarette bans were implemented in England (May 2020) and Canada (October 2017)., Aims and Methods: Cross-sectional data come from 2021 ITC Youth Tobacco and Vaping Survey respondents aged 16-19 who smoked in the past 30 d in England (N = 715) and Canada (N = 419). Adjusted logistic regression models, estimated separately for each country, examined sociodemographic correlates of usually smoking menthol cigarettes (reporting currently most often smoking menthol cigarettes) overall, and by past 30-d use of any menthol accessories (e.g., filters, capsules). Youth reported the cigarette variety they smoked most often, coded as menthol or nonmenthol., Results: Almost no youth who smoked in the past 30 d reported most often smoking a cigarette variety coded as menthol. However, 34.5% (95% CI: 30.4% to 38.9%) of youth who smoke in England and 30.9% (26.0%-36.3%) in Canada reported usually smoking menthol cigarettes, with greater odds of use among those identifying as black, or other race/ethnicity, respectively, compared to white in England (60.0%, aOR = 3.08, p = .001; 47.4%, aOR = 2.27, p = .011) and Canada (43.6%, aOR = 2.44, p = .046; 51.2%, aOR = 2.92, p = .001). Among those who reported usually smoking menthol cigarettes in England (N = 223) and Canada (N = 108), 71.7% (64.0%-78.2%) and 51.5% (41.1%-61.7%) reported using menthol accessories., Conclusions: After menthol cigarette bans in England and Canada, approximately one-third of youth who smoked reported usually smoking menthol cigarettes, with disproportionately higher use among those identifying as black and other race/ethnicity. Menthol accessories accounted for most menthol cigarette use. Closing regulatory loopholes is critical to advancing public health equity., Implications: Use of menthol cigarette accessories (eg, filters, cards, capsules) among youth who smoked was prevalent after implementation of menthol cigarette bans in England and Canada, and there was disproportionately higher use among those who identified as black and any other race/ethnicity. Efforts are therefore required to close regulatory loopholes of menthol cigarette bans. Findings further support countries, such as the United States, proposing menthol cigarette bans which extend coverage to accessories. More comprehensive menthol bans that also restrict accessories are likely to be more effective in reducing flavored tobacco use among young people and in advancing health equity., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.)

Several nicotine vaping product (NVP) device types are available to consumers, and many people who smoke report vaping to help them quit. This study included data from the Wave 3 (2020) ITC Smoking and Vaping Survey in the US, Canada, and England and included 2324 adults who were smoking cigarettes and vaping at least weekly. Device types currently used most often (disposables, cartridges/pods, or tank systems) were assessed using weighted descriptive statistics. Multivariable regression analyses were used to compare differences between respondents who reported vaping to quit smoking ('yes' vs. 'no/don't know') by device type, overall and by country. Overall, 71.3% of respondents reported vaping to help them quit smoking, with no country differences (p = 0.12). Those using tanks (78.7%, p < 0.001) and cartridges/pods (69.5%, p = 0.02) were more likely to report this reason for vaping than those using disposables (59.3%); respondents using tanks were also more likely than those using cartridges/pods (p = 0.001) to report this reason. By country, respondents in England using cartridges/pods or tanks (vs. disposables) were more likely to report vaping to quit smoking (with no difference between cartridges/pods and tanks). In Canada, respondents using tanks were more likely to report vaping to quit smoking than those using cartridges/pods or disposables (no difference between disposables and cartridges/pods). No significant differences by device type were found in the US. In conclusion, most adult respondents who smoked and vaped reported using either cartridges/pods or tanks, which were associated with greater odds of vaping for the purpose of quitting smoking versus disposables, with some country variations., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: KMC has in the past and continues to serve as a paid expert witness in litigation filed against cigarette manufacturers. DH has served as a paid expert witness on behalf of governments and public health authorities in legal challenges against tobacco and vaping companies. GTF has served as an expert witness or consultant for governments defending their country’s policies or regulations in litigation. GTF and SG served as paid expert consultants to the Ministry of Health of Singapore in reviewing the evidence on plain/standardized packaging. None of the other authors have any conflict of interests to declare., (© 2023 The Author(s).)

Background and Aims: Tobacco and nicotine marketplaces have diversified over the past decade, including with the introduction of heated tobacco products (HTPs), such as the brand IQOS. HTPs typically heat tobacco to generate an aerosol that is inhaled. HTP nomenclature is lacking, and how HTP users define and identify themselves remains understudied. Research in this area is important because language can construct identity, and identity can shape behaviour. This study aimed to explore users' language choice when describing IQOS use, and how language relates to user identity., Methods: Qualitative interviews in London, United Kingdom, with 30 adult current and former IQOS users. Analyses were guided by Iterative Categorization., Results: Overall, participants expressed confusion and a lack of suitable terminology for how to describe IQOS use. Verbs such as heating and IQOSing were rarely endorsed. Most often, participants reverted to smoking when describing IQOS use and commonly referred to HEETS (tobacco sticks) as cigarettes. Yet the lack of combustion, electronic device, cleaner experience and perceived reductions in health risks led some to frame IQOS as distinct from smoking. Vaping was generally considered inappropriate for describing IQOS use. Participants also manipulated language to suit their circumstances and manage their identity, whereas some IQOS users embraced the terms smoking and smoker, most were eager to distinguish between using IQOS and being labelled a smoker because of the associated negative connotations and to align with perceptions of IQOS use as a better, less harmful behaviour. Instead, when describing their identity, IQOS users more willingly identified as vapers, or ex-smokers, or created new identities (e.g. HEET user)., Conclusions: People who use or have used IQOS (a brand of heated tobacco product) are ambiguous about IQOS terminology. Participants in this study commonly referred to IQOS use as smoking for lack of a more suitable term, but also resisted being labelled as smokers, a choice that may influence smoking cessation. Clear terminology must be used in surveys and by healthcare professionals when asking about cigarette smoking and e-cigarette and heated tobacco product use., (© 2022 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.)

Competing Interests: Competing interests: DH has served as a paid expert witness in legal challenges against tobacco and vaping companies.

Background: Little is known about population-level differences between adults who exclusively smoke cigarettes and those who smoke cigarettes and also use cannabis (co-consumers). Thus, this study describes differences on sociodemographic, cigarette-dependence, health and behavioral variables, and risk perceptions associated with smoking cannabis., Methods: This cross-sectional study included 6941 respondents from the 2020 ITC Four Country Smoking and Vaping Survey (US, Canada, Australia, England). Adult daily cigarette smokers were included and categorized as: cigarette-only smokers (never used cannabis/previously used cannabis, but not in the past 12 months, n = 4857); occasional co-consumers (cannabis use in the past 12 months, but < weekly use, n = 739); or regular co-consumers (use cannabis ≥ weekly, n = 1345). All outcomes were self-reported. Regression models were conducted on weighted data., Results: Overall, 19.9 % of respondents reported regular cannabis co-use and 10.1 % reported occasional co-use. Regular co-use was highest in Canada (27.2 %), followed by the US (24.4 %), England (12.7 %) and Australia (12.3 %). Compared to cigarette-only smokers, regular co-consumers were more likely to be male and report chest/breathing problems (p < 0.001). All co-consumers were more likely to be younger, have lower income, be experiencing financial stress, reside in Canada, have depressive symptoms, use alcohol more frequently and binge drink, use other tobacco/nicotine products, and perceive smoking cannabis as low health risk and less harmful than smoking cigarettes (all p < 0.001). Cigarette dependence measures were similar between co-consumers and cigarette-only smokers (all p ≥ 0.05)., Conclusions: Although there were no differences on cigarette dependence measures between daily cigarette smokers who do and do not use cannabis, there are several other risk factors that may affect tobacco use and abstinence among co-consumers (e.g., greater depression, high-risk alcohol consumption). Thus, tobacco cessation treatment may require multi-pronged strategies to address other health behaviors. Continued surveillance is needed to determine the nature and health implications of co-use considering changing policies, markets, and products., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. KMC has served as paid expert witness in litigation filed against cigarette manufacturers. GTF and DH have served as expert witnesses on behalf of governments in litigation involving the tobacco industry., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

This study examined reasons why adults who currently smoke or formerly smoked cigarettes use nicotine vaping products (NVPs) by vaping frequency (daily vs. weekly) stratified by smoking status. This cross-sectional study included 3070 adults from the 2020 ITC Four Country Smoking and Vaping Survey (Australia, Canada, England, United States) who reported using a NVP (vaping) at least weekly and who either currently smoke ( n = 2467) or formerly smoked ( n = 603). Respondents were asked to select the reason(s) they use NVPs, including to manage their smoking (reduce/quit or remain quit) and/or for reasons unrelated to managing smoking (e.g., to save money, enjoyment, flavours). We found that both current and former smokers endorsed an average of six reasons for vaping, with those vaping daily reporting significantly more reasons than those vaping weekly. Among current smokers, 72.8% reported vaping may help them quit smoking, 13.0% reported vaping to reduce smoking but not to quit, and 14.2% reported vaping only for reasons other than to reduce or quit smoking. The most common reason for vaping among current smokers was to reduce smoking (81.3%). Current smokers vaping daily were significantly more likely than those vaping weekly to report using a NVP to reduce smoking, for enjoyment, to reduce harm to themselves and others, to quit smoking, likeable flavours, and to save money. The most common reason cited for vaping by respondents who formerly smoked was enjoyment, with those who vaped daily more likely than those who vaped weekly to report vaping for enjoyment and to reduce harm to themselves. Nearly all reported vaping to help stay abstinent from smoking (92.3%), with no significant difference by vaping frequency. In conclusion, a majority of respondents reported using NVPs to manage their smoking (reduce/quit smoking or remain quit), particularly those vaping daily. Those who were vaping daily also endorsed a greater number of reasons other than managing smoking relative to those who were vaping weekly.

Introduction: There is mixed evidence as to whether nicotine vaping products (NVPs) can help adults who smoke transition away from cigarettes. This study investigated if self-reported attempts to quit smoking and smoking cessation, over a period of either 18 or 24 months, differed between respondents who initiated nicotine vaping versus those who did not. Outcome comparisons were made between those who: (1) initiated vaping vs. those who did not; (2) initiated daily or non-daily vaping vs. those who did not; and (3) initiated daily or non-daily vaping between surveys and continued to vape at follow-up (daily or non-daily) vs. those who did not initiate vaping., Methods: This cohort study included 3516 respondents from the ITC Four Country Smoking and Vaping Surveys (Australia, Canada, England, United Sates), recruited at Wave 1 (2016) or 2 (2018) and followed up at Wave 2 (18 months) and/or 3 (2020, 24 months). Adults who smoked daily at baseline and did not have a history of regular vaping were included. Initiation of vaping was defined as beginning to vape at least monthly between surveys. Respondents indicated whether they made an attempt to quit smoking between surveys. Smoking cessation was defined as those who self-reported no longer smoking cigarettes at follow-up., Results: Relative to those who did not initiate vaping, initiation of any daily vaping between surveys was associated with a greater likelihood of smokers making a cigarette quit attempt (p < 0.001) and quitting smoking (p < 0.001). Among smokers who attempted to quit smoking, initiation of daily vaping was associated with a greater likelihood of being abstinent from smoking at follow-up (p = 0.001). Respondents who initiated vaping between surveys and were vaping daily at follow up were significantly more likely to have attempted to quit smoking (p < 0.001) and to have quit smoking (p < 0.001) than those who did not initiate vaping. Respondents who initiated non-daily vaping did not differ significantly from those who did not initiate vaping on any of the outcome measures., Conclusions: Daily NVP use was associated with increased attempts to quit smoking and abstinence from smoking cigarettes. These findings are consistent with the concept that complete cigarette substitution may be more likely to be achieved when smokers vape nicotine daily., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Importance: Menthol cigarettes were prohibited in England in May 2020 and nationally in Canada in October 2017 but remain permitted in the US. Evidence on the outcomes of menthol cigarette bans among youth outside of Canada, and the characteristics of youth smokers, is lacking., Objectives: To evaluate the outcomes of menthol cigarette bans on youth menthol cigarette smoking and to characterize youth menthol cigarette smokers in terms of demographics and cigarette consumption and dependence., Design, Setting, and Participants: This survey study uses data from online repeat cross-sectional International Tobacco Control Youth Tobacco and Vaping Surveys conducted in 2018, 2019, February 2020, and August 2020. Participants included past 30-day smokers aged 16 to 19 years. Data analysis was performed from March 2021 to January 2022., Main Outcomes and Measures: Usually smoke a brand of cigarettes that was menthol, including capsule., Exposures: Menthol cigarette ban, comparing 3 countries over time: Canada, where a ban already existed, England, where a ban was implemented during the study, and the US, where no national ban was present. Age, sex, race, and consumption and dependence were also examined by menthol smoking in each country, and in England before vs after the ban., Results: The analytical sample comprised 7067 participants aged 16 to 19 years, of whom 4129 were female and 5019 were White. In England, the weighted percentage of youth smokers who reported smoking a menthol or capsule cigarette brand was stable in the 3 survey waves before the menthol ban (2018 to February 2020, 9.4% vs 12.1%; adjusted odds ratio [AOR], 1.03; 95% CI, 0.99-1.06; P = .15) but decreased to 3.0% after the ban (February 2020 vs August 2020, AOR, 1.07; 95% CI, 1.04-1.10; P < .001). The decrease between February and August 2020 in England was similar across all demographic groups but was greater among youth who perceived themselves as addicted to cigarettes (AOR, 0.37; 95% CI, 0.41-0.97; P = .04). In the 2 comparison countries, menthol or capsule smoking was stable across all waves (2018 to August 2020: US, 33.6%-36.9%; Canada, 3.1%-2.3%) and was more prevalent in the US than in England (AOR, 5.58; 95% CI, 4.63-6.72; P < .001). Menthol or capsule smoking was also more prevalent among smokers in England who were female vs male (10.9% vs 7.2%; AOR, 1.04; 95% CI, 1.01-1.06; P = .002); among smokers in the US who identified as Black vs White (60.6% vs 31.9%; AOR, 1.33; 95% CI, 1.23-1.44; P < .001) or who were frequent smokers (AOR, 1.07; 95% CI, 1.01-1.13; P = .03), smoked more cigarettes per day (2-5 vs 1, AOR, 1.09; 95% CI, 1.02-1.15; P = .006; >5 vs 1, AOR, 1.10; 95% CI, 1.03-1.18; P = .007), or had urges to smoke every or most days (AOR, 1.08; 95% CI, 1.02-1.14; P = .006); and among smokers in Canada who perceived themselves as addicted to cigarettes (AOR, 1.02; 95% CI, 1.00-1.03; P = .01)., Conclusions and Relevance: In this survey study, the proportion of youth smokers who smoke menthol (including capsule) cigarettes decreased substantially after the menthol ban in England. This association was consistent across all demographic groups. Perceived addiction among menthol smokers was also lower where menthol cigarettes were banned.

Introduction: Some jurisdictions have implemented nicotine vaping product (NVP) flavor restrictions because of concerns about rising adolescent use. However, little is known how these restrictions may impact adult vapers. This study describes the level of support and predictive behavioral responses to a hypothetical NVP ban on non-tobacco flavors among regular adult vapers who only use flavors that would be banned., Methods: Data came from 851 regular vapers (all current or ex-smokers) participating in the 2020 ITC Four Country Smoking and Vaping Survey in Canada, England, and the United States (US). A random sample of respondents in each country received and completed the questions about flavor bans: (1) do you support or oppose a ban on all non-tobacco flavors; and (2) what would you do if all flavors were banned, with the exception of tobacco in the US, and tobacco and menthol in Canada and England. Those who used tobacco-flavored or unflavored NVPs were excluded from all analyses, and additionally, vapers of menthol flavor in Canada and England were excluded from Aim 2., Results: Overall, 53.6% of vapers were strongly opposed to flavor bans, 28.2% were opposed, 9.3% were in support, 3.6% were in strong support, and 5.2% did not know. Predicted behavioral responses were: 28.8% would continue vaping an available flavor, 28.3% would find a way to get their banned flavor(s), 17.1% would stop vaping and smoke instead, 12.9% said that they would stop vaping and not smoke, and 12.9% do not know what they would do. Responses to a potential flavor ban largely varied by smoking and vaping status, and by the level of support of a flavor restriction policy., Conclusions: At this time, it is not clear what net population-level consequences would occur if non-tobacco flavored NVPs were prohibited. While a majority of vapers in this study opposed this policy, and many vapers would not be willing to switch to available flavors, there was considerable variability in predicted behavioral responses., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Delay discounting (DD) and time perspective (TP) are conceptually related constructs that are theorized as important determinants of the pursuit of future outcomes over present inclinations. This study explores their predictive relationships for smoking cessation., Methods: 5006 daily smokers at a baseline wave provided 6710 paired observations of quitting activity between two waves. Data are from the International Tobacco Control (ITC) smoking and vaping surveys with samples from the USA, Canada, England, and Australia, across three waves conducted in 2016, 2018 and 2020. Smokers were assessed for TP and DD, plus smoking-specific predictors at one wave of cessation outcomes defined as either making a quit attempt and/or success among those who tried to quit which was ascertained at the subsequent survey wave., Results: TP and DD were essentially uncorrelated. TP predicted making quit attempts, both on its own and controlling for other potential predictors but was negatively associated with quit success. By contrast, DD was not related to making quit attempts, but high DD predicted relapse. The presence of financial stress at baseline resulted in some moderation of effects., Conclusions: Understanding the mechanisms of action of TP and DD can advance our understanding of, and ability to enhance, goal-directed behavioural change. TP appears to contribute to future intention formation, but not necessarily practical thought of how to achieve goals. DD is more likely an index of capacity to effectively generate competing future possibilities in response to immediate gratification.

Background and Aims: In May 2017, black-and-white text nicotine addiction warning labels ('warnings') and health and safety leaflets ('leaflets') became mandatory for nicotine vaping products (NVPs) in England, in accordance with the European Union's Tobacco Products Directive. We compared changes over time in noticing warnings and leaflets, recall of warnings about nicotine and concerns about using NVP due to noticing warnings in England, compared with Canada, the US and Australia, where no warnings and leaflets were mandated., Design: 19 005 adult (aged 18+) NVP users, smokers and quitters of cigarettes and NVP from the 2016 and 2018 International Tobacco Control Four Country Smoking and Vaping Surveys in England, Canada, the US and Australia, recruited via probability and non-probability sampling., Findings: Noticing warnings increased in England from 4.9% (2016) to 9.4% (2018) (adjusted OR/AOR=1.64, 95% CI=1.15-2.36); this change was larger than changes in Canada (AOR=2.51, 95% CI=1.71-3.69) and the US (AOR=2.22, 95% CI=1.45-3.39). Recall of a nicotine warning increased in England from 86% (2016) to 94.9% (2018) (AOR=5.50, 95% CI=1.57-19.27) but not significantly elsewhere. Noticing leaflets increased in England from 14.6% (2016) to 19.1% (2018) (AOR=1.42, 95% CI=1.15-1.74); this change was larger than in Canada (AOR=1.42, 95% CI=1.12-1.79), the US (AOR=1.55, 95% CI=1.17-2.06) and Australia (AOR=1.51, 95% CI=1.02-2.22). Among those noticing warnings, concern about NVP use did not change significantly between 2016 and 2018 (all countries p>0.081)., Conclusions: Introduction of mandatory NVP warnings and leaflets in England was associated with small increases in noticing them but not with changes in concerns about NVP use., Competing Interests: Competing interests: MC has received payment as a consultant to Pfizer for service on an external advisory panel to assess ways to improve smoking cessation delivery in healthcare settings. MC also has served as paid expert witness in litigation filed against the tobacco industry. GTF, DH and JT have served as expert witnesses on behalf of governments in litigation involving the tobacco industry. AM is a UK National Institute for Health Research (NIHR) Senior Investigator., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Aims: Evidence on the effectiveness of electronic cigarettes (ECs) to facilitate abstinence from smoking is limited. The current study aimed to estimate the relative effectiveness of ECs and smoking cessation medication compared with using no help, accounting for frequency of use of ECs., Design: Four consecutive wave-to-wave transitions (waves 1-2, 2-3, 3-4 or 4-5) of a longitudinal online survey collected between 2012 and 2017 were analysed. Time between waves ranged between 12 and 17 months. Cigarette smokers at the baseline wave who attempted to quit smoking between waves were included., Setting: United Kingdom PARTICIPANTS: A total of 1155 respondents (aged 18-81, 56.1% male, 64.6% in social grade C2DE, 93.8% white) provided 1580 pairs of observations for the primary analysis., Measurements: Primary outcome: abstinence from smoking for at least 1 month at follow-up; secondary outcome: at least 1 month's abstinence from smoking between baseline and follow-up. The main predictor was stop smoking aid used (No help, nicotine replacement therapy only, smoking cessation medication only, disposable/cartridge EC, refill/modular EC, combination), adjusted for demographics., Findings: Primary Compared with using no help, the odds of abstinence were increased by daily use of disposable/cartridge ECs (OR = 3.31 (1.32, 8.26), P = .010) and daily use of refill/modular ECs (OR = 5.47 (2.70, 11.11), P < .001). Odds were reduced by non-daily use of disposable/cartridge ECs (OR = 0.23 (0.08-0.63), P = .005), and by use of disposable/cartridge ECs to quit and no longer using at follow-up (OR = 0.10 (0.16-0.62), P < .013). Secondary Results were similar to the primary outcome; however, odds of abstinence were also increased by use of smoking cessation medication (OR = 4.15 (1.79, 9.62), P = .001)., Conclusions: When used daily, electronic cigarettes appear to facilitate abstinence from smoking when compared with using no help., (© 2021 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.)

Purpose: The tobacco and nicotine market is diversifying. Implications for public health will depend on trends in use, including overall use, and who is using these products. This study examined differences over time (2017-2019), across countries (Canada, England, the United States (US)), and by smoking and vaping, in use of other tobacco/nicotine products and overall use., Methods: The study includes online repeat cross-sectional surveys of youth aged 16-19 years in Canada (N = 11,714), England (N = 11,170), US (N = 11,838) in 2017, 2018, and 2019. Past 30-day use of tobacco/nicotine products (any, cigarette, e-cigarette, other combusted [cigars/cigarillos/waterpipe], other non-combusted [smokeless tobacco/nicotine replacement therapies) were examined by country, year, and, for other combusted and non-combusted products, past 30-day cigarette smoking and vaping. Use of emerging products (IQOS, nicotine pouches) was explored in 2018-2019., Results: From 2017 to 2019, use of any product increased in Canada (17.1%-23.2%, AOR = 1.07 [95% CI = 1.04-1.09]) and the US (18.0%-24.0%, AOR = 1.06 [1.04-1.09]) but not England (20.8%-21.7%, AOR = 1.01 [.99-1.03]). Use of other combusted products (cigars/cigarillos/waterpipe) showed little change (Canada: 8.1%-7.8%; England: 6.3%-7.3%; US: 8.6%-8.5%; p ≥ .151). Use of other non-combusted products (smokeless/nicotine replacement therapies) increased in all countries (Canada: 1.5%-3.2%, AOR = 1.02 [1.01-1.02]; England: 1.4%-2.6%, AOR = 1.02 [1.01-1.03]; US: 3.3%-4.9%, AOR = 1.02 [1.01-1.02]). Vaping increased in all countries (Canada: 8.4%-17.8%; England: 8.7%-12.6%; United States: 11.1%-18.5%; all p < .001). Smokers and vapers reported greater use of other combusted and non-combusted products than those who neither smoked/vaped (p < .001). Emerging product use was rare (≤1.5%)., Conclusions: Youth past 30-day tobacco and nicotine product use increased from 2017 to 2019 in Canada and the United States, largely due to increases in vaping and other non-combusted products. "Other" tobacco/nicotine products were used predominantly by youth who smoked cigarettes and/or vaped., (Copyright © 2021 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Introduction: This study retrospectively describes smoking cessation aids, cessation services, and other types of assistance used by current and ex-smokers at their last quit attempt in four high-income countries., Aims and Methods: Data are from the Wave 3 (2020) International Tobacco Control Four Country Smoking and Vaping Survey in Australia, Canada, England, and the United States (US). Eligible respondents were daily smokers or past-daily recent ex-smokers who made a quit attempt/quit smoking in the last 24-months, resulting in 3614 respondents. Self-reported quit aids/assistance included: nicotine vaping products (NVPs), nicotine replacement therapy (NRT), other pharmacological therapies (OPT: varenicline/bupropion/cytisine), tobacco (noncombustible: heated tobacco product/smokeless tobacco), cessation services (quitline/counseling/doctor), other cessation support (e.g., mobile apps/website/pamphlets, etc.), or no aid., Results: Among all respondents, at last quit attempt, 28.8% used NRT, 28.0% used an NVP, 12.0% used OPT, 7.8% used a cessation service, 1.7% used a tobacco product, 16.5% other cessation support, and 38.6% used no aid/assistance. Slightly more than half of all smokers and ex-smokers (57.2%) reported using any type of pharmacotherapy (NRT or OPT) and/or an NVP, half-used NRT and/or an NVP (49.9%), and 38.4% used any type of pharmacotherapy (NRT and/or OPT). A quarter of smokers/ex-smokers used a combination of aids. NVPs and NRT were the most prevalent types of cessation aids used in all four countries; however, NRT was more commonly used in Australia relative to NVPs, and in England, NVPs were more commonly used than NRT. The use of NVPs or NRT was more evenly distributed in Canada and the US., Conclusions: It appears that many smokers are still trying to quit unassisted, rather than utilizing cessation aids or other forms of assistance. Of those who did use assistance, NRT and NVPs were the most common method, which appears to suggest that nicotine substitution is important for smokers when trying to quit smoking., Implications: Clinical practice guidelines in a number of countries state that the most effective smoking cessation method is a combination of pharmacotherapy and face-to-face behavioral support by a health professional. Most quit attempts however are made unassisted, particularly without the use of government-approved cessation medications. This study found that about two in five daily smokers used approved cessation medications (nicotine replacement therapy (NRT) or other approved pharmacotherapies, such as varenicline). Notably, nicotine substitution in the form of either NRT and nicotine vaping products (NVPs) were the most common method of cessation assistance (used by one in two respondents), but the proportion using NRT and/or NVPs varied by country. Few smokers who attempted to quit utilized cessation services such as stop-smoking programs/counseling or quitlines, despite that these types of support are effective in helping smokers manage withdrawals and cravings. Primary healthcare professionals should ask their patients about smoking and offer them evidence-based treatment, as well as be prepared to provide smokers with a referral to trained cessation counselors, particularly when it comes to tailoring intensive treatment programs for regular daily smokers. Additionally, healthcare providers should be prepared to discuss the use of NVPs, particularly if smokers are seeking advice about NVPs, wanting to try/or already using an NVP to quit smoking, have failed repeatedly to quit with other cessation methods, and/or if they do not want to give up tobacco/nicotine use completely., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.)

Background: Harm perceptions of tobacco and nicotine products can influence their use and could be targeted by policies to change behaviour. IQOS was introduced to the UK in 2016, and there is little independent qualitative research on IQOS harm perceptions. This study explored the perceived health harms of IQOS to users and those exposed to the emissions, what shapes these perceptions, and what participants wanted to know about the harms of IQOS., Methods: Qualitative interviews in London, UK, with 30 adult current and former IQOS users who currently smoked or quit smoking in the last 2 years., Results: IQOS was perceived as less harmful than smoking but not risk-free, although there was great uncertainty. Influences on harm perceptions were consolidated into six themes: (1) dominance of manufacturer claims influenced perceptions that IQOS is less harmful than smoking to users and those around them, although mistrust of the tobacco industry heightened scepticism about harms; (2) limited independent and long-term research led to uncertainty about harms, although some participants trusted IQOS would not be marketed if it were very harmful. Participants wanted more independent and long-term studies into harm; (3) appearance of HEETS (tobacco sticks) packaging conveyed reduced harm because packets were 'pretty', without graphic/specific warnings, although written warnings conveyed some harm. Participants wanted more information on HEETS packets about harms; (4) process of heating and HEETS contents-heating, compared with burning, tobacco was perceived to produce fewer harmful chemicals, while tobacco, nicotine, and chemicals in HEETS were perceived to cause some harm. Participants wanted clarification about the harms of heating tobacco and HEETS ingredients; (5) improvements in physical health and personal appearance reduced perceptions of harm; (6) differences in sensory experiences (taste, sight, smell) when using IQOS over smoking reduced perceptions of harm, while 'black' deposits inside IQOS led to perceptions of some harm. Reduced volume and smell of IQOS emissions also reduced perceptions of harm to non-users exposed to the emissions., Conclusions: IQOS was perceived as less harmful than smoking but not risk-free, although there was great uncertainty. Participants wanted clarification about IQOS harms from independent sources in accessible forms, specifically related to HEETS ingredients, heating tobacco, and emissions to others.

Objective: To assess trends in daily smokers' social norms and opinions of smoking between 2002 and 2015 in Canada, the United States, the United Kingdom, and Australia., Method: Data were from wave 1 (2002) to wave 9 (2013-2015) of the longitudinal International Tobacco Control Four Country Survey (Canada, the United States, the United Kingdom, Australia), involving 23 831 adult daily smokers. Generalized estimating equation logistic regression models, adjusted for demographics and survey design effects, assessed associations of wave and country with outcomes: (A) over half of five closest friends smoke, (B) agreeing that people important to you believe you should not smoke, (C) agreeing that society disapproves of smoking, and (D) negative opinion of smoking., Results: Between 2002 and 2015, adjusting for covariates, (A) over half of five closest friends smoke did not change (56% vs. 55%; adjusted odds ratio [AOR] = 0.95 [95% Confidence Interval = 0.85-1.07]), (B) agreeing that people important to you believe you should not smoke generally decreased (89% vs. 82%; AOR = 0.54 [0.46-0.64]) despite an increase around 2006-2007, (C) agreeing that society disapproves of smoking increased between 2002 and 2006-2007 (83% vs. 87%; AOR = 1.38 [1.24-1.54]) then decreased until 2013-2015 (78%; AOR = 0.74 [0.63-0.88]), and (D) negative opinion of smoking decreased between 2002 and 2010-2011 (54% vs. 49%; AOR = 0.83 [0.75-0.91]) despite an increase around 2005-2006 and at the final wave (2013-2015). Except friend smoking, Canada had the greatest, and the United Kingdom the lowest, antismoking social norms and opinions., Conclusions: Except friend smoking and opinion of smoking, daily smokers' social norms became less antismoking between 2002 and 2015 despite increases around 2006-2007. Several potential explanations are discussed yet remain undetermined., Implications: Increasingly comprehensive tobacco control policies alongside decreasing smoking prevalence in Canada, the United States, the United Kingdom, and Australia have led to the assumption that smoking has become denormalized in these countries. Absent from the literature is any formal assessment of social norms towards smoking over time. Contrary to our hypotheses, this study found that the injunctive social norms of daily smokers became less antismoking between 2002 and 2015, despite increases around 2006-2007. There was no change over time in the proportion of daily smokers who report that over half of their five closest friends smoke., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.)

Background: Social norms have received little attention in relation to electronic cigarettes (EC). The current study examine social norms for EC use and smoking tobacco, and their associations with (i) initiation of EC use, (ii) intention to quit smoking and (iii) attempts to quit smoking., Methods: Cross-sectional and longitudinal data analysis from Waves 1 and 2 of the ITC 6 European Country Survey and corresponding waves from England (the ITC Four Country Smoking and Vaping Survey). Current smokers at baseline, who heard of ECs and provided data at both waves were included (n = 3702). Complex samples logistic regression examined associations between the outcomes and descriptive (seeing EC use in public, close friends using ECs/smoking) and injunctive (public approves of ECs/smoking) norms, adjusting for country, demographics, EC use and heaviness of smoking., Results: In longitudinal analyses, seeing EC use in public at least some days was the only social norm that predicted initiation of EC use between waves (OR = 1.66, 95%CI = 1.08-2.56). In the cross-sectional analysis, having an intention to quit was associated with seeing EC use in public (OR = 1.37, 95%CI = 1.04-1.81) and reporting fewer than three close friends smoke (OR = 0.59, 95%CI = 0.44-0.80). There was no association between any social norm and making a quit attempt between waves., Conclusions: Initiation of EC use is predicted by seeing EC use in public, which was also associated with greater intention to quit smoking. Friends' smoking was associated with lower intention to quit. These findings may allay concerns that increased visibility of ECs is renormalizing smoking amongst current smokers., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.)

Background: This study assesses differences in social norms towards smoking and vaping among youth across countries (England, Canada, US) and smoking and vaping status., Methods: Data are from the 2017 ITC Youth Tobacco and Vaping Survey, among youth age 16-19 in England (N = 3444), Canada (N = 3327), and US (N = 3509). Prevalence of friend smoking, friend vaping, peer approval of smoking, and peer approval of vaping were estimated. Adjusted logistic regression models were estimated for each norm to assess associations with country, smoking status, and vaping status, adjusting for sociodemographics, alcohol use, and marijuana use., Results: 47% and 52% reported friend smoking and vaping respectively. Perceived peer approval of vaping (44%) was almost double that of smoking (23%). Compared with England, fewer Canadian and US youth reported friend smoking (Canada: AOR = 0.71 [95% CI = 0.62-0.82]; US: AOR = 0.54 [0.47-0.62]) and peer approval of smoking (Canada: AOR = 0.74 [0.63-0.87]; US: AOR = 0.78 [0.67-0.91]), yet more reported peer approval of vaping (Canada: AOR = 1.23 [1.08-1.41]; US: AOR = 1.30 [1.14-1.48]). More Canadian than English youth reported friend vaping (AOR = 1.17 [1.02-1.36]). Friend smoking, peer approval of smoking, and friend vaping were more common among smokers and vapers (all p < .02). Peer approval of vaping was more common among vapers but less common among smokers (all p < .044)., Conclusions: Youth had more positive vaping than smoking norms. English youth reported the most pro-smoking but least pro-vaping norms in adjusted models; this was unexpected given country differences in regulatory environments. Norms towards both products were associated with use, with some evidence of cross-product associations between norms and behaviours., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Because only limited and controversial data exist concerning the respiratory effects of clonidine in humans, the authors evaluated the respiratory effects of clonidine alone and in combination with morphine, in 12 healthy adult males. Subjects received clonidine (0.3-0.4 mg orally), morphine (0.21 mg/kg intramuscularly), or the same doses of the two drugs combined, at three separate sessions in a randomized fashion. The study was balanced for all possible sequences of drug administration. Blood pressure, heart rate, hemoglobin oxygen saturation via finger pulse oximetry, and ventilatory and occlusion pressure responses to CO2 were obtained before and 20, 40, 60, 90, 120, 180, 240, 300, and 360 min after administration of drug or drug combination. Systolic blood pressure decreased significantly only in the clonidine and clonidine plus morphine groups (P less than 0.05). Hemoglobin oxygen saturation decreased by a statistically significant (P less than 0.05), though clinically minor, degree only in the morphine or morphine plus clonidine groups. Clonidine alone did not depress the slope of either the ventilatory or the occlusion pressure response to CO2. In addition, clonidine did not significantly worsen morphine-induced depression of the slope of the ventilatory and occlusion pressure responses in the drug combination group. Both the ventilatory and occlusion pressure responses to CO2 were shifted to the right in all three drug groups (P less than 0.05) but were shifted to a significantly lesser degree by clonidine alone than by morphine and morphine plus clonidine. In healthy young adult males, clonidine alone produces little respiratory depression and does not significantly potentiate morphine-induced respiratory depression.

More than 80 deaths have occurred after the use of midazolam (Versed), often in combination with opioids, to sedate patients undergoing various medical and surgical procedures. We investigated the respiratory effects of midazolam (0.05 mg.kg-1) and fentanyl (2.0 micrograms.kg-1) in volunteers. The incidence of hypoxemia (oxyhemoglobin saturation less than 90%) and apnea (no spontaneous respiratory effort for 15 s) and the ventilatory response to carbon dioxide were evaluated. Midazolam alone produced no significant respiratory effects. Fentanyl alone produced hypoxemia in half of the subjects and significant depression of the ventilatory response to CO2, but did not produce apnea. Midazolam and fentanyl in combination significantly increased the incidence of hypoxemia (11 of 12 subjects) and apnea (6 of 12 subjects), but did not depress the ventilatory response to CO2 more than did fentanyl alone. Adverse reactions linked to midazolam and reported to the Department of Health and Human Services highlight apnea- and hypoxia-related problems as among the most frequent adverse reactions. Seventy-eight per cent of the deaths associated with midazolam were respiratory in nature, and in 57% an opioid had also been administered. All but three of the deaths associated with the use of midazolam occurred in patients unattended by anesthesia personnel. We conclude that combining midazolam with fentanyl or other opioids produces a potent drug interaction that places patients at a high risk for hypoxemia and apnea. Adequate precautions, including monitoring of patient oxygenation with pulse oximetry, the administration of supplemental oxygen, and the availability of persons skilled in airway management are recommended when benzodiazepines are administered in combination with opioids.

The authors evaluated the effect of transdermal scopolamine on the incidence of postoperative nausea, retching, and vomiting after outpatient laparoscopy in a double-blind, placebo-controlled study. A Band-Aid-like patch containing either scopolamine or placebo was placed behind the ear the night before surgery. Anesthesia was induced with fentanyl (0.5-2 micrograms/kg iv), thiopental (3-5 mg/kg iv), and succinylcholine (1-1.5 mg/kg iv) and maintained with isoflurane (0.2-2%) and nitrous oxide (60%) in oxygen. Scopolamine-treated patients had less nausea, retching, and vomiting compared with placebo-treated patients (P = 0.0029). Severe nausea and/or vomiting was present in 62% of the placebo group but only 37% of those getting the scopolamine patch. Repeated episodes of retching and vomiting were also less frequent in the scopolamine group compared with the placebo group (23% vs. 41%; P = 0.0213) as was the need for additional antiemetic therapy (13% vs. 32%; P = 0.0013). Patients in the scopolamine group were also discharged from the hospital sooner (4 +/- 1.3 vs. 4.5 +/- 1.5 h; P = 0.0487). Side effects were more frequent among those patients treated with the scopolamine patch (91% vs. 45%; P less than 0.05) but were not troublesome. The authors conclude that transdermal scopolamine is a safe and effective antiemetic for outpatients undergoing laparoscopy.

The magnitude and duration of analgesia and respiratory depression induced by fentanyl (1.0, 2.0, and 4.0 micrograms/kg) and sufentanil (0.1, 0.2, and 0.4 microgram/kg) after intravenous administration over 30 s were measured in 30 healthy young adult male volunteers divided into three groups and studied in a double-blind, randomized fashion. Each volunteer received one dose of fentanyl or sufentanil and no sooner than 48 h later, the corresponding equipotent dose of the other opioid. End-tidal CO2 and ventilatory and occlusion pressure responses to CO2 rebreathing were used to measure drug-induced respiratory effects. Analgesic effects were assessed by changes in the pain threshold to electric shock applied to the forearm. Plasma levels of fentanyl and sufentanil were measured by radioimmunoassay. Testing and sampling intervals were 5, 30, 60, 90, 120, 240, 300, and 360 min after drug administration. The magnitude and duration of depression of the ventilatory and occlusion pressure response were significantly less with sufentanil compared with fentanyl, irrespective of dose. Ventilatory and occlusion pressure responses returned to control values by 30 and 30 min, respectively, after sufentanil and by 240 and 120 min, respectively, after fentanyl. Statistically significant elevations of the pain threshold were, however, greater and longer lasting after sufentanil compared with fentanyl. Pain threshold returned to control values 180 min after sufentanil but only 90 min after fentanyl. These results suggest that sufentanil may provide better patient comfort with less respiratory depression than does fentanyl.

Beta-adrenergic blockers have been reported to depress central ventilatory drive. The authors investigated this possibility in a double-blind, randomized fashion in 12 healthy volunteers who received 0.1 mg.kg-1 of propranolol and normal saline intravenously at two separate study sessions. A modified Read rebreathing technique was used. Both ventilatory and occlusion pressure responses to CO2 were measured to help separate peripheral (airway) from central mechanisms. Significant beta blockade was demonstrated by statistically lower heart rate responses to CO2 rebreathing after propranolol, but not normal saline. Nevertheless, propranolol exerted no significant effect on resting end-tidal CO2 or the ventilatory and occlusion pressure responses to CO2. Although health subjects appear to have minimal alterations in their ventilatory response to CO2 after beta-adrenergic blockade, patients with airway disease may still experience significant changes in ventilation. In addition, drug interaction studies may give further insight into the presence or absence of any respiratory effects of propranolol.

Cardiac, respiratory and neurologic abnormalities have been identified as causes of Sudden Infant Death Syndrome (SIDS). Recurrent central apnea (no respiratory effort or nasal/oral airflow) and obstructive apnea (respiratory effort without concurrent nasal/oral airflow) in infants are considered risk factors for SIDS. However, using currently available monitoring techniques, normal activities such as yawns, stretches and swallows cannot be distinquished from short obstructive episodes lasting less than 20 s. A system was developed to more accurately detect obstructive apnea in infants using a miniature microphone placed over the trachea, a cassette tape recorder and a MINC-11 microcomputer. Respiratory sounds were recorded on 5 anesthesized rabbits in which partial and total airway obstruction was artificially induced. Sounds were analyzed by computer using fast Fourier transformations. Amplitude versus frequency was plotted for normal breathing, partial obstruction and total obstruction. Characteristic patterns were identified for each episode demonstrating that acoustic detection of apnea in infants by a microprocessor-based monitor is feasible.

The authors determined whether fentanyl incorporated into a candy lollipop, oral transmucosal fentanyl citrate (OTFC), would cross mucosal tissues of the mouth in sufficient quantities during and after dissolution to produce sedation and/or analgesia. Associated respiratory and circulatory changes, side effects, and plasma concentrations of fentanyl were also measured. The evaluations were done in 28 adult volunteers who received fentanyl citrate in doses of 5, 4, 2, 1, and 0.5 mg in OTFC and rapidly sucked the lollipops (N = 20) or allowed them to passively dissolve (N = 8). Rapid consumption of OTFC resulted in more rapid onset of a pleasant feeling (first subjective sensation) but not more rapid onset of objective sedation or analgesia than passive dissolution. There was a significant correlation between dose of OTFC and magnitude of sedation (P less than 0.001, Spearman rank correlation = -0.82). Higher doses of OTFC produced greater and longer lasting analgesia and respiratory depression and a higher incidence of nausea and vomiting than lower doses, but pruritus (33%-87%) was not related to the dose of OTFC. Heart rate and arterial blood pressures were not changed by any dose of OTFC. The data indicate that low doses of OTFC (0.5 and 1 mg, equivalent to 5-20 micrograms.kg-1 of fentanyl citrate) produce analgesia and sedation with minimal side effects and little respiratory depression in adult volunteers and deserve further evaluation in patients.

The short elimination half-life of vecuronium suggests it may be delivered more efficiently by continuous infusion than by traditional bolus injections. The objective of this study was to compare manual administration with computer-controlled administration. Anesthesia was induced in 22 patients (American Society of Anesthesiologists [ASA] physical status I and II) with fentanyl and sodium thiopental and maintained with halothane and nitrous oxide in oxygen. Neuromuscular function was assessed at the hypothenar eminence and the adductor pollicis (train-of-four stimulation). A bolus of 0.1 mg/kg of vecuronium was given to obtain 100% twitch depression for tracheal intubation. After twitch height returned to 25% of control, relaxation was maintained by traditional bolus injections (group 1, n = 7), manually controlled continuous infusion (group 2, n = 7), or computer-controlled continuous infusion (group 3, n = 8). In all three groups the desired level of relaxation was 90% twitch depression. Variability of relaxation differed significantly among the three groups (group 1: 10.5%, group 2: 12.4%, group 3: 7.1%). Twitch height was more constant with computer control than with either bolus injections or manual infusion (P less than 0.05). There was no statistically significant difference in the drug requirement (group 1: 1.60 microgram/kg/min, group 2: 1.51 microgram/kg/min, group 3: 1.45 microgram/kg/min). Variability in the mechanomyogram (n = 12) was much higher than in the electromyogram (n = 10). Computer-controlled infusion may be a useful adjunct for the anesthesiologist who desires a stable level of patient relaxation when using short-acting, non-depolarizing relaxants.

The authors compared naloxone and nalbuphine as antagonists of opioid-induced respiratory depression to determine the relative efficacies and safety of the two agents. In a double-blind, randomized fashion, 90 anesthetized patients received a mean dose of 25 micrograms/kg fentanyl during surgery. Inadequate spontaneous respirations at the end of anesthesia were treated with either naloxone 0.08 mg or nalbuphine 2.5 mg IV every 2 min while heart rate (HR), systolic and diastolic blood pressures (SBP, DBP), respiratory rate (RR), and tidal volume (TV) were measured at 2-min intervals. Arterial blood samples for analysis of PaCO2, PaO2, and pH were drawn when spontaneous ventilation resumed, and 30 and 60 min later. Narcotic antagonism and respiration were deemed adequate when TV was greater than or equal to 4 ml/kg and RR greater than or equal to 8 breaths/min. Heart rate, SBP, DBP, TV and RR were recorded, as were the occurrence of renarcotization (RR less than 8) and analgesic requirements every 5 min during the recovery room stay. Sixty of 90 patients required narcotic antagonism at the end of surgery. No patient required more than three doses (0.24 mg) of naloxone or four doses (10 mg) of nalbuphine. Both antagonists produced similar and moderate increases in SBP and HR while restoring adequate spontaneous ventilation. There were no significant differences in TV, RR, or arterial blood gases (ABGS) between the two groups after narcotic reversal.(ABSTRACT TRUNCATED AT 250 WORDS)

Ventilatory inductive plethysmography allows noninvasive monitoring of patient ventilation. Patient movements unrelated to breathing introduce severe errors in ventilator inductive plethysmographic measurements and restrict its usefulness. The purpose of this research was to develop and test a microprocessor-based real-time digital signal processor that uses an adaptive filter to detect patient movements unrelated to breathing. The adaptive filter processor was tested for retrospective identification of artifacts in 20 male volunteers who performed the following specific movements between epochs of quiet, supine breathing: raising arms and legs (slowly, quickly, once, and several times), sitting up, breathing deeply and rapidly, and rolling from a supine to a lateral decubitus position. Flow was simultaneously measured directly with a pneumotachography attached to a mouthpiece. A multilinear regression was used to continuously calculate the calibration constants that relate the pneumotachographic and ventilatory inductive plethysmographic signals. Ventilatory inductive plethysmographic data were then processed, and results scored. There were a total of 166 movements. The calibration coefficients changed dramatically in 146 (88%) of the 166 movements. These movements would have significant errors on ventilatory inductive plethysmographic flow calculation. The changes lasted for the duration of the movements and returned to baseline within two to three breaths. The changes in the coefficients were five or more times larger than the variability around baseline during quiet, supine breathing. All of the total body movements and changes in breathing patterns were detected accurately. The filter detected 46 of 53 upper body movements, 34 of 36 lower body movements, 38 of 38 total body movements, and 19 of 19 breathing pattern changes where the calibration changed.(ABSTRACT TRUNCATED AT 250 WORDS)