Page 45 - REBRAME - Revista Brasileira de Medicina de Emergência

BRAZILIAN JOURNAL OF EMERGENCY MEDICINE VOLUME 03 | NÚMERO 1 / 39-44

INTRODUCTION PATHOPHYSIOLOGY AND CLINICAL
PRESENTATION
Since 2014, a new tobacco product, electronic cigarettes,
has been widely used by the young population, As mentioned above, as there is no standardization of
especially teenagers, which has brought great concern substances present in these devices, there is no absolute
to pulmonologists [1,2] . This new product consists of mechanism for all of them. However, devices with
an electronic device designed to vaporize chemical nicotine have mostly propylene glycol (PG) and glycerol
compounds, whether or not they contain nicotine [3]. (GLY), substances known for their irritating characteristic
Depending on the model, the use of these devices is called of the respiratory tract, leading to obstruction and
vaping or Juuling . inflammation [15-17] . In addition, PG and GLY do not
[4]
cross biological membranes and may induce a state
Late effects still remain unknown, due both to the lack of hyperosmotic stress, leading to the secretion of pro-
of manufacturing standards, making it difficult to predict inflammatory cytokines in the lung [18-20] . This mechanism
pulmonary exposure for the generic class of e-cigarettes, can activate inflammatory cascades that result in surfactant
and to the relatively recent introduction of the device to disturbance and small airway collapse, modifying
the market . However, even though they are sold as a ventilation/perfusion regulation and thus interfering with
[5]
safer alternative to conventional tobacco products or as gas exchange . Furthermore, nicotine, present in more
[21]
a transition for individuals who wish to quit smoking [6,17] , than 90% of e-cigarettes, can cause bronchoconstriction
the early consequences of the use of these devices have of the large airways when inhaled [22] .
been observed and there are already reports of fatal cases.
of acute respiratory failure triggered by these devices [8-10] . Few patients diagnosed with EVALI underwent lung
biopsy, but the histopathological findings are consistent
The first report of significant lung disease from vaping with acute lung injury such as acute fibrosing pneumonia,
was in 2019 in the United States [11] . The term EVALI diffuse alveolar damage, and foamy macrophages . In
[23]
(E-cigarette or Vaping product use-Associated Lung Injury) addition, CDC researchers have already identified Vitamin
was introduced shortly afterwards, simultaneously with E acetate in the bronchoalveolar lavage of patients with
the increase in the number of cases of the disease [12] . In EVALI as a possible factor of disease severity. The proposed
this sense, the present study aims to review the available mechanism is the disruption of alveolar surfactant, leading
scientific literature on EVALI.
to a decrease in surface tension, alveolar collapse and lung
injury .
[24]
METHODOLOGY
Classic clinical findings consist of nonspecific respiratory
symptoms such as shortness of breath, chest pain, cough
This is a descriptive and exploratory study, a narrative
review of the literature, including studies that address and/or hemoptysis. Most patients also report gastrointestinal
EVALI. For this, the PubMed database was accessed, using symptoms such as nausea, vomiting and/or diarrhea and
the following descriptors: “EVALI”, “E-Cigarette”, “Acute constitutional symptoms such as fever, chills, weight loss
[25]
[14]
lung injury”, “Respiratory failure”, “Vaping” and “Juuling”. and fatigue . Werner et al. observed a lower incidence
We also included relevant studies found in the reference of gastrointestinal symptoms in fatal cases than in non-fatal
list of selected studies. cases (53% and 80% respectively), indicating a greater
severity of the disease in the predominantly respiratory
form. Laboratory findings are also nonspecific, with an
EPIDEMIOLOGY elevation of leukocyte count and erythrocyte sedimentation
rate being present [25] .
Patients with EVALI are mostly young adult males [13] . In
2020, a multicenter study analyzed 2558 non-fatal and 50 DIAGNOSTIC AND IMAGING EXAMS
fatal cases of the disease, noting a predominance of men in
both categories (67% and 53%, respectively). Age, on the According to the CDC, the diagnostic criteria for EVALI
other hand, showed divergence between the categories: are: history of vaping within the last 90 days, consistent
78% of non-fatal cases were in individuals under 35 years radiological findings, and ruling out infection and other
of age, while 73% of fatal cases were in individuals over differential diagnoses. However, some pulmonologists
35 years of age. In addition, both groups had high levels of include bronchoscopy, bronchoalveolar lavage, and lung
psychiatric disorders (41% and 65%), indicating a possible biopsy [26] .
risk factor for e-cigarette use .
[14]

40 | REBRAME | REVISTA BRASILEIRA DE MEDICINA DE EMERGÊNCIA