Challenges for the development of alternative low-cost ventilators during COVID-19 pandemic in Brazil

The COVID-19 pandemic has brought concerns to managers, healthcare professionals, and the general population related to the potential mechanical ventilators' shortage for severely ill patients In Brazil, there are several initiatives aimed at producing alternative ventilators to cover this gap To assist the teams that work in these initiatives, we provide a discussion of some basic concepts on physiology and respiratory mechanics, commonly used mechanical ventilation terms, the differences between triggering and cycling, the basic ventilation modes and other relevant aspects, such as mechanisms of ventilator-induced lung injury, respiratory drive, airway heating and humidification, cross-contamination risks, and aerosol dissemination After the prototype development phase, preclinical bench-tests and animal model trials are needed to determine the safety and performance of the ventilator, following the minimum technical requirements Next, it is mandatory going through the regulatory procedures as required by the Brazilian Health Regulatory Agency (Agencia Nacional de Vigilancia Sanitaria - ANVISA) The manufacturing company should be appropriately registered by ANVISA, which also must be notified about the conduction of clinical trials, following the research protocol approval by the Research Ethics Committee The registration requisition of the ventilator with ANVISA should include a dossier containing the information described in this paper, which is not intended to cover all related matters but to provide guidance on the required procedures A pandemia por COVID-19 tem deixado os gestores, os profissionais de saude e a populacao preocupados com a potencial escassez de ventiladores pulmonares para suporte de pacientes graves No Brasil, ha diversas iniciativas com o intuito de produzir ventiladores alternativos para ajudar a suprir essa demanda Para auxiliar as equipes que atuam nessas iniciativas, sao expostos alguns conceitos basicos sobre fisiologia e mecanica respiratoria, os termos comumente utilizados no contexto da ventilacao mecanica, as fases do ciclo ventilatorio, as diferencas entre disparo e ciclagem, os modos ventilatorios basicos e outros aspectos relevantes, como mecanismos de lesao pulmonar induzida pela ventilacao mecanica, pacientes com drive respiratorio, necessidade de umidificacao de vias aereas, risco de contaminacao cruzada e disseminacao de aerossois Apos a fase de desenvolvimento de prototipo, sao necessarios testes pre-clinicos de bancada e em modelos animais, a fim de determinar a seguranca e o desempenho dos equipamentos, seguindo requisitos tecnicos minimos exigidos Entao, e imprescindivel passar pelo processo regulatorio exigido pela Agencia Nacional de Vigilancia Sanitaria (ANVISA) A empresa responsavel pela fabricacao do equipamento deve estar regularizada junto a ANVISA, que tambem deve ser notificada da conducao dos testes clinicos em humanos, seguindo protocolo de pesquisa aprovado pelo Comite de Etica em Pesquisa O registro do ventilador junto a ANVISA deve ser acompanhado de um dossie, composto por documentos e informacoes detalhadas neste artigo, que nao tem o proposito de esgotar o assunto, mas de nortear os procedimentos necessarios