ABSTRACT The tobacco epidemic has been one of the biggest public health threats, and smoking is one of the world's largest preventable causes of premature death. An estimated 15.4% of all deaths in the world are attributable to tobacco smoking. The present review aims to describe addiction to tobacco smoking and vaping. Tobacco and vaping devices contain nicotine, a highly addictive drug, which explains why smoking is so prevalent and persistent. Electronic cigarettes are a group of novel nicotine or tobacco products that have rapidly gained popularity in recent years. Electronic cigarette devices allow for the use of other drugs, including THC, while the lax regulation may allow for the introduction of toxic compounds that can lead to acute or subacute toxicity, such as the e-cigarette- or vaping-associated lung injury that has been linked to vitamin E acetate. In addition, regular vapers and heated tobacco devices emit toxins, although at lower concentrations than burned tobacco. However, more and more side effects have been identified. No new effective treatment for nicotine addiction has been developed recently, despite its huge adverse impact on overall health and other outcomes. As for the primary line of medications, the last one started in 2006, the varenicline, demonstrating a low interest in developing new medications against smoking, an unacceptable state of affairs, given the huge impact of smoking on morbidity and mortality.

Abstract: Introduction: in the international classification of diseases (ICD-10), deaths of primary respiratory origin are scattered across several sections, uncommonly compiled together as often happens with neoplasias and cardiovascular deaths, leading to underestimation of the impact of respiratory diseases and the influx of resources to the patients. Material and methods: mortality statistics for Mexico for 2021 coded with the ICD-10 were reviewed. All causes of death, primarily respiratory, were added, both from section J, and from those distributed in other sections, and compared against those that occurred in 2015. Results: in 2015, 79,383 respiratory deaths (12.6% of the total) were coded, of which 54,173 were in the respiratory «J» codes and the rest (25,210) in other codes, while in 2021 there were 349,491 (31% of the total), an impressive increase due to the COVID-19 pandemic. The most common causes of death were COPD, pneumonia-influenza, malignant tumors of the chest, neonatal respiratory deaths, disorders of the pulmonary circulation, interstitial diseases, asthma, and tuberculosis. Conclusions: respiratory diseases are an important cause of death in Mexico with and without respiratory pandemic, so the appropriate training of personnel and granting sufficient resources to care for the sick must be supported.

Resumen: Introducción: en la clasificación internacional de enfermedades (ICD-10) las muertes de origen primario respiratorio se encuentran dispersas por varios apartados y cuando no se agrupan todas se infravalora su importancia, lo que puede reducir el impacto público de las enfermedades respiratorias y la afluencia de recursos y tratamientos para los pacientes. Material y métodos: se revisaron las estadísticas de mortalidad de México de 2021 codificada con la décima clasificación internacional (ICD-10). Se sumaron todas las causas de muerte primariamente respiratoria tanto del apartado J, como las distribuidas en otros apartados y se compararon contra las ocurridas en 2015. Resultados: se codificaron en 2015, 79,383 muertes respiratorias (12.6% del total), de las cuales 54,173 estaban en los códigos respiratorios «J» y el resto (25,210) en otros códigos mientras que en 2021 fueron 349,491 (31% del total), un incremento impresionante debido a la pandemia de COVID-19. Dejando de lado el COVID-19, las causas más comunes de muerte de origen respiratorio fueron la enfermedad pulmonar obstructiva crónica, la neumonía-influenza, los tumores malignos del tórax, las muertes respiratorias neonatales, los trastornos de la circulación pulmonar, las enfermedades intersticiales, el asma y la tuberculosis. Conclusiones: las enfermedades respiratorias son causa importante de muerte en México con y sin pandemia respiratoria, por lo que se debe apoyar el entrenamiento de personal capacitado y recursos suficientes para la atención de los enfermos.

Abstract: Spirometry is the most widely used and standardized respiratory function test. In 2019, the American Thoracic Society and the European Respiratory Society updated the international guidelines for its execution. The COVID-19 pandemic forced the establishment of better biosafety parameters and has renewed interest in respiratory medicine in the world, including physiological evaluation. The present manuscript summarizes these changes incorporating recommendations and suggestions for countries with limited resources.

Resumen: La espirometría es la prueba de función respiratoria más utilizada y estandarizada. En el año 2019, la Sociedad Americana del Tórax y la Sociedad Respiratoria Europea actualizaron los lineamientos internacionales para su ejecución. La pandemia de COVID-19 ha obligado a establecer mejores parámetros de bioseguridad y ha renovado el interés por la medicina respiratoria en el mundo, incluyendo la evaluación funcional. El presente manuscrito es una propuesta de procedimiento de espirometría ajustado a los cambios e incorpora recomendaciones y sugerencias para países con recursos limitados.

ABSTRACT Background The values of arterial blood gases (ABG) change with altitude above sea level; empirical verification is essential because ventilatory acclimatization varies with ethnicity and a population's adaptation. Objective The aim of the study was to describe ABG in a healthy population residing at 2,240 meters above sea level, to identify the mean level of alveolar ventilation (PaCO2), and to know whether a progressive increase in PaCO2 occurs with age and the impact of increasing body mass index (BMI). Methods We conducted a cross-sectional study in a referral center for respiratory diseases in Mexico City. Associations among variables with correlation coefficient and regression models of PaO2, SaO2, and P(A-a)O2 as dependent variables as a function of age, BMI, minute ventilation, or breathing frequency were explored. Results Two hundred and seventeen healthy subjects were evaluated with a mean age of 40 ± 15 years, mean of the PaO2 was 71 ± 6 mmHg, SaO2 94% ± 1.6%, PaCO2 30.2 ± 3.4 mmHg, HCO3 20 ± 2 mmol/L, BE-2.9 ± 1.9 mmol/L, and the value of pH was 7.43 ± 0.02. In a linear regression, the main results were PaO2 = 77.5-0.16*age (p < 0.0001) and with aging P(A-a)O2 tended to increase 0.12 mmHg/year. PaCO2 in women increased with age by 0.075 mmHg/year (p = 0.0012, PaCO2 =26.3 + 0.075*age). SaO2 and PaO2 decreased significantly in women with higher BMI 0.14% and 0.52 mmHg per kg/m2, (p = 0.004 and 0.002 respectively). Conclusion Mean PaCO2 was 30.7 mmHg, implying a mean alveolar ventilation of around 30% above that at sea level.

ABSTRACT A large world population resides at moderate altitudes. In the Valley of Mexico (2240 m above sea level) and for patients with respiratory diseases implies more hypoxemia and clinical deterioration, unless supplementary oxygen is prescribed or patients move to sea level. A group of individuals residing at 2500 or more meters above sea level may develop acute or chronic mountain disease but those conditions may develop at moderate altitudes although less frequently and in predisposed individuals. In the valley of México, at 2200 m above sea level, re-entry pulmonary edema has been reported. The frequency of other altitude-related diseases at moderate altitude, described in skiing resorts, remains to be known in visitors to Mexico City and other cities at similar or higher altitudes. Residents of moderate altitudes inhale deeply the city's air with all pollutants and require more often supplementary oxygen.

Abstract: Objective: To evaluate the effectiveness of SARS-CoV-2 vaccines to avoid death and intubation in hospitalized patients with Covid-19. Materials and methods: We present an analysis of 3 565 hospitalizations for SARS-CoV-2 in people over 20 years of age, reported for public health purposes by 10 specialty hospitals, comparing those discharged for improvement (2 094) with those who died (1 471) in mixed models of logistic regression adjusted for age, sex, number of comorbidities and the reporting hospital as a random variable. Results: A complete vaccination schedule, with five types of vaccine available, had a protective effect for death or intubation (OR: 0.67, CI95%: 0.54,0.83, 33% protection) and for death (OR: 0.80, CI95%: 0.64,0.99, 20% protection) compared to those who had not been vaccinated. All the applied vaccines in the Mexican program showed a protective effect with an OR<0.8, with variable confidence intervals. Conclusions: Even in patients previously vaccinated and hospitalized with severe Covid-19, a history of vaccination reduces the risks of being intubated and dying.

Resumen: Objetivo: Evaluar la efectividad de las vacunas contra SARS-CoV-2 para evitar muerte e intubación en pacientes hospitalizados con Covid-19. Material y métodos: Se presentó un análisis de 3 565 hospitalizaciones por SARS-CoV-2 de personas mayores de 20 años de edad, reportadas con fines de salud pública por 10 hospitales de especialidad. Se comparó a los egresados por mejoría (2 094) con los fallecidos (1 471) en modelos mixtos de regresión logística ajustados por edad, sexo, número de comorbilidades y el hospital como variable aleatoria. Resultados: Un esquema completo de vacunación, con cinco tipos de vacunas disponibles, tuvo un efecto protector para muerte o intubación (RM: 0.67, IC95%: 0.54,0.83, 33% de protección); y para muerte (RM: 0.80, IC95%: 0.64,0.99, 20% de protección) estos datos se compararon con los que no habían sido vacunados. Todas las vacunas aplicadas mostraron un efecto protector con un RM<0.8, con intervalos de confianza variables. Conclusiones: El antecedente de vacunación reduce los riesgos de ser intubado y morir, aun en pacientes previamente vacunados y hospitalizados con Covid-19 grave.

Abstract: Chronic obstructive pulmonary disease (COPD) is the third leading cause of global death, and the disease burden is further increased by multiple comorbidities, including some psychological disorders, like anxiety and depression, among others. This interplay between mental health and COPD has become a subject of intense study in recent years. Our objective was to describe the psychological factors associated with COPD, the interplay of factors leading to psychological impacts, and to analyze the effective treatment and intervention alternatives available. A narrative literature search was performed in PubMed and Cochrane Library, by using a snow-ball search technique to identify papers published on the subject. A search was conducted for relevant original articles with emphasis on years 2015-2021. Relevant was the emphasis of a multidisciplinary team to support patients with COPD, experts on psychological factors associated with the disease, especially on anxiety and depression. Treatments available, including psychological interventions demonstrated an improvement in quality of life, adherence to treatments, reduced hospitalizations, symptomatology and exacerbations.

Resumen: La enfermedad pulmonar obstructiva crónica (EPOC) es la tercera causa principal de muerte a nivel mundial, y la carga de la enfermedad aumenta por múltiples comorbilidades, incluidos algunos trastornos psicológicos, como ansiedad y depresión, entre otros. Esta interacción entre la salud mental y la EPOC se ha convertido en un tema de intenso estudio en los últimos años. Nuestro objetivo fue describir los factores psicológicos asociados con la EPOC, la interacción de factores que conducen a un impacto en la enfermedad y analizar las alternativas de tratamiento e intervención efectivas disponibles. Se realizó una búsqueda de literatura narrativa en PubMed y Cochrane Library, utilizando una técnica de búsqueda de bola de nieve para identificar artículos publicados sobre el tema. Se realizó una búsqueda de artículos originales relevantes con énfasis en los años 2015-2021. Fue relevante el énfasis de un equipo multidisciplinario de apoyo a los pacientes con EPOC, resulta relevante la evaluación de factores psicológicos asociados a la enfermedad, especialmente ansiedad y depresión. Los tratamientos disponibles, incluidas las intervenciones psicológicas, demostraron una mejora en la calidad de vida, adherencia a los tratamientos, reducción de hospitalizaciones, sintomatología y exacerbaciones.

Abstract: Telemedicine worldwide and in Mexico has been very useful during the COVID-19 pandemic. Being able to provide health care services where distance is a critical factor, at a time when health services are saturated, and where face-to-face care implies a risk for both the health care provider and the patients, it has been indispensable during the pandemic. The speed with which telemedicine services have been implemented globally has been very different. There are still great challenges to be solved in order to provide this type of care worldwide. It should be noted that telemedicine complements patient care, rather than replacing the usual face-to-face care.

Resumen: La telemedicina a nivel mundial y en México ha sido de gran utilidad durante la pandemia por COVID-19. Poder prestar servicios de atención médica donde la distancia es un factor crítico, en un momento en el que se encuentran saturados los servicios de salud, y donde la atención presencial implica un riesgo, tanto para el proveedor de atención en salud como para los pacientes, ha sido indispensable durante la pandemia. La rapidez con la que se han implementado servicios de telemedicina a nivel mundial ha sido muy diferente. Aún quedan grandes retos por resolver para poder brindar este tipo de atención a nivel mundial. Cabe resaltar que la telemedicina viene a complementar la atención del paciente, más que a sustituir la habitual atención presencial.

Abstract: Objective: To describe the possible risks associated to smoking in the spread and complications of Covid-19, emphasizing in the benefits of quitting smoking. Materials and methods: The narrative review methodology and the established process for Cochrane rapid reviews were used. Results: The scientific evidence related to smoking and Covid-19 remains limited. However, there is an already documented trend in cross-sectional, clinical studies and meta-analyses on the increased risk of adverse outcomes with Covid-19 associated with tobacco use. Conclusions: It is necessary to issue a warning that persons who smoke would have greater risks in the Covid-19 pandemic, which add to the many already known risks of tobacco use. Thus, quitting smoking becomes a relevant preventive measure to better confront SARS-CoV-2.

Resumen: Objetivo: Describir los posibles riesgos asociados de tabaquismo con contagio y complicaciones por Covid-19, haciendo hincapié en los beneficios de dejar de fumar. Material y métodos: Se utilizó la metodología de revisión narrativa y el proceso establecido para las revisiones rápidas Cochrane. Resultados: La evidencia científica relacionada con el tabaquismo y Covid-19 todavía es limitada. Existe una tendencia ya documentada en estudios clínicos transversales y metaanálisis del aumento del riesgo de resultados adversos para Covid-19 asociados con el consumo de tabaco. Conclusiones: Es necesario advertir que las personas que fuman tendrán mayores riesgos en la pandemia de Covid-19, los cuales se suman a los muchos ya conocidos del consumo de tabaco, de modo que dejar de fumar se convierte en una medida preventiva relevante para enfrentar mejor el SARS-CoV-2.

Abstract: Introduction: Forced spirometry is a diagnostic and prognostic tool in asthma and Chronic Obstructive Pulmonary Disease (COPD). The low use of the test is a problem that persists, particularly in the first level of care, generating underdiagnosis, and inadequate diagnosis of obstructive diseases. Learning the maneuver and interpretation of it is not a mandatory part of the academic program of medical students and residents routinely in many countries, including Mexico. Objective: To evaluate the possible reasons for the low use of spirometry in the first level of Care in Mexico and the impact of an educational program on the declarative an procedural learning of the test. Material and methods: Face-to-face training in spirometry, of 6 hours, was carried out to the staff of the primary care centers with the highest prevalence of acute respiratory infections in the Mexican Republic (phase I). Participants solved a survey about spirometry use before attending the course. Evaluation of 13 questions and a graphic interpretation exercise was applied before and after the session. They were instructed to deliver spirometry tests of biological controls to INER and receive feedback from pulmonologist. The staff that remained active was invited to become certified in spirometry based on NIOSH (phase II). The scores obtained pre and post-intervention during phase I were analyzed; as well as during phase II in the subgroup of participants who remained active. Results: 579 subjects attended the phase I training. 397 (68.6%) solved the pre-course survey. 83.9 and 78.9% reported attending more than one patient with the diagnosis of Asthma or COPD, respectively. 53.8% requested none spirometry in their monthly consultation. Among the causes, 39.7% consider it very important do not know how to perform it and not to have the equipment to do the test (30.5%). After the course, a significant improvement in declarative knowledge was observed compared to the diagnostic evaluation. 53.85 (RIC 38.46-69.23) versus 23.08 (RIC 7.69-30.77) respectively. After 10 months (7.17-14.5), only 77 participants went to phase II and took the spirometry certification course (18 hours) demonstrating stability in the theoretical score despite the elapsed time and good quality scores in the theoretical and practical evaluations after the 2nd intervention. Conclusion: The knowledge about spirometry is minimal and poorly used in the primary care of our country. Possible causes are a lack of continuous training and infrastructure. After a short training, there is a significant improvement in the learning of the test, which is held months later and is reinforced with a second training of longer duration. However, after a year of follow-up, new staff replaced the original one in a large percentage. What makes it necessary to establish more cost-effective educational modalities as tele-education.

Resumen: Introducción: La espirometría forzada es una herramienta diagnóstica y pronóstica en asma y en la enfermedad pulmonar obstructiva crónica. El poco uso de esta prueba es un problema persistente, en particular en el primer nivel de atención, lo que genera subdiagnóstico y diagnóstico inadecuado de enfermedades respiratorias obstructivas. El aprendizaje de la maniobra espirométrica y su interpretación no son obligatorios en los programas académicos de las facultades de medicina en muchos países incluyendo México. Objetivo: Evaluar los posibles motivos del poco uso de la espirometría en el primer nivel de atención en México y el impacto de un programa educativo en el aprendizaje declarativo y procedimental de la prueba. Material y métodos: Se desarrolló un entrenamiento presencial de seis horas dirigido al personal de primer nivel perteneciente a los centros con mayor prevalencia de infecciones respiratorias agudas en México (fase I). Los participantes resolvían una encuesta sobre el uso de la espirometría antes de acudir al curso. Se aplicó una evaluación de 13 preguntas y un ejercicio de interpretación gráfica antes y después del curso. Se instruyó a los participantes sobre el envío de controles biológicos al Instituto Nacional de Enfermedades Respiratorias para poder continuar en el proyecto y ser invitados al curso de certificación de fase II, basado en los estándares del Instituto Nacional para la Seguridad y Salud Ocupacional (NIOSH). Se analizaron los puntajes pre- y posintervención del curso de fase I, así como del curso de fase II en aquellos participantes que continuaron activos. Resultados: 579 sujetos realizaron el entrenamiento de fase I, de los cuales, 397 (68.6%) contestaron la encuesta inicial, en la cual 83.9 y 78.9% reportaron atender más de un paciente con el diagnóstico de asma o enfermedad pulmonar obstructiva crónica, respectivamente. El 53.8% de los encuestados no solicita ninguna espirometría al mes. Entre los motivos destacan el desconocimiento sobre la ejecución de la prueba (39.7%) y falta de equipo para realizarla (30.5%). Después del curso se observó una mejoría significativa en el conocimiento declarativo, comparado con la evaluación diagnóstica 53.85 (RIC 38.46-69.23) versus 23.08 (RIC 7.69-30.77), respectivamente. Después de 10 meses (7.17-14.5) sólo 77 sujetos tomaron el curso de Certificación en Espirometría (18 horas) o fase II, demostrando estabilidad en la puntuación teórica a pesar del tiempo transcurrido y puntuaciones de buena calidad en las evaluaciones (teóricas y prácticas) posteriores a la segunda intervención. Conclusión: El conocimiento sobre espirometría es pobre en el primer nivel de atención de nuestro país. Las posibles causas son la falta de formación e infraestructura continuas. Tras un breve entrenamiento, se produce una mejora significativa en el aprendizaje de la prueba, que se mantiene meses después y se refuerza con un segundo entrenamiento de mayor duración. Sin embargo, el personal nuevo reemplaza al original en un gran porcentaje, lo que hace necesario establecer modalidades educativas rentables como la teleeducación.