E-cigarette or vaping induced lung injury: A case series and literature review

Cardiopulmonary Impact of Electronic Cigarettes and Vaping Products: A Scientific Statement From the American Heart Association

Vaping and electronic cigarette (e-cigarette) use have grown exponentially in the past decade, particularly among youth and young adults. Cigarette smoking is a risk factor for both cardiovascular and pulmonary disease. Because of their more limited ingredients and the absence of combustion, e-cigarettes and vaping products are often touted as safer alternative and potential tobacco-cessation products. The outbreak of e-cigarette or vaping product use-associated lung injury in the United States in 2019, which led to >2800 hospitalizations, highlighted the risks of e-cigarettes and vaping products. Currently, all e-cigarettes are regulated as tobacco products and thus do not undergo the premarket animal and human safety studies required of a drug product or medical device. Because youth prevalence of e-cigarette and vaping product use was as high as 27.5% in high school students in 2019 in the United States, it is critical to assess the short-term and long-term health effects of these products, as well as the development of interventional and public health efforts to reduce youth use. The objectives of this scientific statement are (1) to describe and discuss e-cigarettes and vaping products use patterns among youth and adults; (2) to identify harmful and potentially harmful constituents in vaping aerosols; (3) to critically assess the molecular, animal, and clinical evidence on the acute and chronic cardiovascular and pulmonary risks of e-cigarette and vaping products use; (4) to describe the current evidence of e-cigarettes and vaping products as potential tobacco-cessation products; and (5) to summarize current public health and regulatory efforts of e-cigarettes and vaping products. It is timely, therefore, to review the short-term and especially the long-term implications of e-cigarettes and vaping products on cardiopulmonary health. Early molecular and clinical evidence suggests various acute physiological effects from electronic nicotine delivery systems, particularly those containing nicotine. Additional clinical and animal-exposure model research is critically needed as the use of these products continues to grow.

The unseen cloud: a survey of vaping practices and the acquisition of vaping products within the UK

BACKGROUND

Vaping of cannabinoid-based products and informal acquisition of vaping products were associated with the outbreak of E-cigarette or vaping associated lung injury (EVALI) in the USA. Current prevalence of cannabinoid-based vaping within the UK is not known and literature regarding the acquisition of vaping products is limited.

AIM

To estimate the prevalence of nicotine-based, nicotine-free and cannabinoid-based product vaping within the UK and to determine where vaping products are acquired.

DESIGN AND METHODS

A voluntary online survey of individuals aged 16 and over within the UK was conducted using a convenience sample. Data were collected on respondent demographics, smoking/vaping history and acquisition of e-liquids/products.

RESULTS

A total of 2478 responses were included. Median age 45 years (interquartile range 35-57). Prevalence of current vaping of nicotine-based e-liquids, nicotine-free e-liquids and cannabinoid-based products was 14.4%, 11.2% and 5.49%, respectively. Current nicotine-based and nicotine-free vaping was most prevalent in 25-34 years olds (22.4% and 19.2% of respondents). Current cannabinoid-based vaping was most prevalent in 16-24 years olds. The most common 'ever' used cannabinoid-based products were cannabidiol oil/cannabigerol oil and cannabis leaves (4.8%). Specialist vaping stores were the most common source of 'ever' acquisition for all products. 36.8% and 40.5% of respondents who had ever vaped nicotine-based and nicotine-free e-liquids reported prior acquisition from informal sources.

CONCLUSION

This survey reported a higher prevalence of current cannabinoid-based vaping within the UK (5.5%) than previously reported in the USA (2.0%). In addition to the informal acquisition of vaping products as demonstrated within the survey, these results highlight potential underestimation of the risk of EVALI within the UK.

E-cigarette or vaping-associated lung injury (EVALI): a review of international case reports from outside the United States of America

INTRODUCTION

E-cigarette or vaping-associated lung injury has been reported extensively throughout the United States without a corresponding number of international cases. Cannabinoid-based products have been implicated in the majority of cases.

OBJECTIVES

To collate published reports of E-cigarette or vaping-associated lung injury outside the United States and to identify the reasons behind the discrepancy in reported cases between the United States and the international community.

METHODS

PubMed and Healthcare Databases Advanced Search were used to identify published case reports of E-cigarette or vaping-associated lung injury prior to February 2021 using the search terms "e-cigarette", "e-cigarettes", "vaping", "vape" and, "lung injury", "pulmonary", "respiratory". Cases occurring in the United States were excluded. Non-United States case reports were excluded if they did not meet the Centers for Disease Control and Prevention "probable case" criteria. This requires use of a vaping device within 90 days of symptom onset, the presence of pulmonary infiltrates on plain film chest radiography or ground glass opacities on computerised tomography, clinical suspicion that infection was not the underlying cause of lung injury, and the absence of other plausible medical processes to account for the presentation. Patient demographics, nature of exposure, symptomatology and outcome were compared to 125 cases from three regional United States based case series, which were chosen on the basis of having complete data for these comparative factors.

RESULTS

Seventeen international cases from 13 countries were identified for analysis. There was a male predominance in both non-United States and United States cohorts (76% vs 58-83%), with a marginally higher median patient age in non-United States cases (31 vs 27, 19, 27 years). Reported use of nicotine/flavoured e-liquids was more common in non-United States cases (100% vs 58-67%), and use of cannabinoid-based products was less common (24% vs 78-92%). The most common symptoms across all cohorts were shortness of breath (76% vs 85-91%), cough (59% vs 78-83%) and fever (47% vs 78-83%). The majority of patients were hypoxic (76% vs 69-86%) and required hospital admission (88% vs 90-94%). Fewer of the non-United States patients required intensive care admission (24% vs 55-67%) though their median length of stay was longer (15 days vs 5, 6, 7 days).

DISCUSSION

Uniformity amongst non-United States cases in regards to nicotine based and/or flavoured e-liquid exposure may underestimate the role of these substances in e-cigarette or vaping-associated lung injury. This is consistent with prior United States based research demonstrating increased presentations to emergency departments prior to the recognised "outbreak" of e-cigarette or vaping-associated lung injury at a time of increased nicotine based e-liquid uptake. A longer length of hospital stay, lower rate of intensive care admission and a higher rate of bronchoscopy in the non-United States cohort could be indicative of clinician inexperience internationally. It is unclear why the non-United States cases also had a lower incidence of gastrointestinal symptoms however this may also be explained by poorer diagnostic awareness.

CONCLUSIONS

E-cigarette or vaping-associated lung injury is not limited to cannabinoid-based products. Apparent similarities in patient demographics, clinical features, and clinical course between non-United States and United States cases raise concern for underreporting of E-cigarette or vaping- associated lung injury internationally.

Vaping-Associated Lung Injury: A Review

Since commercial development in 2003, the usage of modern electronic cigarette (e-cigarette) continues to increase amongst people who have never smoked, ex-smokers who have switched to e-cigarettes, and dual-users of both conventional cigarettes and e-cigarettes. With such an increase in use, knowledge of the irritative, toxic and potential carcinogenic effects on the lungs is increasing. This review article will discuss the background of e-cigarettes, vaping devices and explore their popularity. We will further summarise the available literature describing the mechanism of lung injury caused by e-cigarette or vaping use.

E-cigarette vaping associated acute lung injury (EVALI): state of science and future research needs

"E-Cigarette (e-cig) Vaping-Associated Acute Lung Injury" (EVALI) has been linked to vitamin-E-acetate (VEA) and Δ-9-tetrahydrocannabinol (THC), due to their presence in patients' e-cigs and biological samples. Lacking standardized methodologies for patients' data collection and comprehensive physicochemical/toxicological studies using real-world-vapor exposures, very little data are available, thus the underlying pathophysiological mechanism of EVALI is still unknown. This review aims to provide a comprehensive and critical appraisal of existing literature on clinical/epidemiological features and physicochemical-toxicological characterization of vaping emissions associated with EVALI. The literature review of 161 medical case reports revealed that the predominant demographic pattern was healthy white male, adolescent, or young adult, vaping illicit/informal THC-containing e-cigs. The main histopathologic pattern consisted of diffuse alveolar damage with bilateral ground-glass-opacities at chest radiograph/CT, and increased number of macrophages or neutrophils and foamy-macrophages in the bronchoalveolar lavage. The chemical analysis of THC/VEA e-cig vapors showed a chemical difference between THC/VEA and the single THC or VEA. The chemical characterization of vapors from counterfeit THC-based e-cigs or in-house-prepared e-liquids using either cannabidiol (CBD), VEA, or medium-chain triglycerides (MCT), identified many toxicants, such as carbonyls, volatile organic compounds, terpenes, silicon compounds, hydrocarbons, heavy metals, pesticides and various industrial/manufacturing/automotive-related chemicals. There is very scarce published toxicological data on emissions from THC/VEA e-liquids. However, CBD, MCT, and VEA emissions exert varying degrees of cytotoxicity, inflammation, and lung damage, depending on puffing topography and cell line. Major knowledge gaps were identified, including the need for more systematic-standardized epidemiological surveys, comprehensive physicochemical characterization of real-world e-cig emissions, and mechanistic studies linking emission properties to specific toxicological outcomes.

Cannabis Vaping Among Youth and Young Adults: a Scoping Review

Purpose of Review

The purpose of this review was to describe the state-of-the-literature on research specific to cannabis vaping among youth and young adults.

Recent Findings

Out of 1801 records identified, a total of 202 articles met eligibility criteria for inclusion in this review. Most of this literature (46.0% of studies) was specific to the health effects of cannabis vaping, particularly EVALI (e-cigarette and vaping associated lung injury). Other research areas identified in the review included the etiology (24.3%) and epidemiology (24.8%) of cannabis vaping, in addition to articles on regulation (8.4%) and marketing (5.5%) of the same.

Summary

Cannabis vaping is increasingly common among youth and young adults and more prevalent is settings where recreational use for adults has been legalized. The literature documents a number of negative health effects of cannabis vaping for young people, along with risk factors and reasons for the same.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40429-022-00413-y.

VAPIng into ARDS: Acute Respiratory Distress Syndrome and Cardiopulmonary Failure

"Modern" vaping involving battery-operated electronic devices began approximately one dozen years and has quickly evolved into a multibillion dollar industry providing products to an estimated 50 million users worldwide. Originally developed as an alternative to traditional cigarette smoking, vaping now appeals to a diverse demographic including substantial involvement of young people who often have never used cigarettes. The rapid rise of vaping fueled by multiple factors has understandably outpaced understanding of biological effects, made even more challenging due to wide ranging individual user habits and preferences. Consequently while vaping-related research gathers momentum, vaping-associated pathological injury (VAPI) has been established by clinical case reports with severe cases manifesting as acute respiratory distress syndrome (ARDS) with examples of right ventricular cardiac failure. Therefore, basic scientific studies are desperately needed to understand the impact of vaping upon the lungs as well as cardiopulmonary structure and function. Experimental models that capture fundamental characteristics of vaping-induced ARDS are essential to study pathogenesis and formulate recommendations to mitigate harmful effects attributable to ingredients or equipment. So too, treatment strategies to promote recovery from vaping-associated damage require development and testing at the preclinical level. This review summarizes the back story of vaping leading to present day conundrums with particular emphasis upon VAPI-associated ARDS and prioritization of research goals.

Pulmonary Function Testing in Patients With E-Cigarette, or Vaping, Product Use-Associated Lung Injury

In 2019 there was an outbreak of respiratory illnesses amongst people who used E-cigarettes. This phenomenon was labeled 'EVALI' which stands for "Electronic cigarette (E-cigarette), or Vaping, Product Use-Associated Lung Injury" and is a life-threatening illness of the lungs associated with E-cigarette use. It is believed to be caused by certain chemicals in E-cigarette cartridges, such as vitamin E acetate, but the exact pathophysiological mechanism is yet to be elucidated. Since 2019, the CDC has recorded over 2800 cases in the United States with over 60 deaths. Though many people recover from EVALI, the long-term implications on pulmonary health are unknown. The purpose of this retrospective study was to demonstrate the pulmonary function test (PFT) findings in a group of patients who recovered from a diagnosis of EVALI. We reviewed the cases of 23 adult patients who presented to two major academic hospitals of the Northwell Health System with confirmed EVALI and followed up in our outpatient clinics with PFTs. Most patients had significantly reduced diffusion capacity (DLCO) demonstrating loss of functioning alveolar units. Given that average follow-up was over a month after discharge, this leads us to believe that EVALI can lead to persistent lung damage. However, further follow-up would be necessary to identify the full impact of E-cigarette use on the pulmonary function. 

Nicotine pharmacokinetics of electronic cigarettes: A pooled data analysis from the literature

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Evaluating the pharmacokinetics of nicotine absorption from electronic cigarettes.

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Nicotine absorption into the blood is influenced by several factors.

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These include e-liquid composition, user behavior and device characteristics.

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Any regulation of nicotine levels in e-liquids should reflect this heterogeneity.

Several regulatory initiatives around the world restrict the amount of nicotine permitted in electronic cigarette liquids in an attempt to reproduce the nicotine delivery of combusted tobacco products, such as cigarettes, and or reduce the risk of consumers absorbing too much nicotine into their body at one time. Such an approach, however, assumes that (i) there is a strong correlation between the levels of nicotine in electronic cigarette liquids and nicotine intake into the body and (ii) that this correlation holds true across the various different types of electronic cigarette devices currently available on the market. In order to test these hypotheses, this study examines the available scientific literature on nicotine intake from electronic cigarettes, as measured by levels in the blood. Analysis of the published data reveals that nicotine absorption into the body is influenced by a combination of many factors, including electronic cigarette liquid composition, user behavior and device characteristics. Notably, it was observed that open-tank (refillable) electronic cigarettes, which often enable users to vary device power, can deliver high nicotine levels to consumers, sometimes at greater doses than a conventional tobacco cigarette, even at the lower nicotine liquid concentrations typically available. For electronic cigarettes to be viable alternative choices to smoking, they should provide consumers with an equally satisfying experience, including in terms of nicotine absorption into the body. Therefore, any regulation seeking to restrict the amount of nicotine in electronic cigarette liquids should take all the factors influencing nicotine intake into account.