Changing patterns of nitrous oxide use and
environmental awareness among Brazilian
anesthesiologists: a nationwide cross-sectional survey

Leopoldo Muniz da Silva; Rafael Souza Fava Nersessian; Ana Claudia Lopes Fernandes Araújo; Vanessa Melo Silva Torres; Désirée Stieven Machado; Saullo Queiroz Silveira; Fernando Nardy Bellicieri; Caroline Tukasan; Gabriel Silva dos Anjos; Helidea de Oliveira Lima; Glenio B. Mizubuti

doi:10.1016/j.bjane.2026.844739

Estudo Original

Changing patterns of nitrous oxide use and environmental awareness among Brazilian anesthesiologists: a nationwide cross-sectional survey

Mudanças nos padrões de uso de óxido nitroso e conscientização ambiental entre anestesiologistas brasileiros: um levantamento transversal nacional

Leopoldo Muniz da Silva, Rafael Souza Fava Nersessian, Ana Claudia Lopes Fernandes Araújo, Vanessa Melo Silva Torres, Désirée Stieven Machado, Saullo Queiroz Silveira, Fernando Nardy Bellicieri, Caroline Tukasan, Gabriel Silva dos Anjos, Helidea de Oliveira Lima, Glenio B. Mizubuti

http://dx.doi.org/10.1016/j.bjane.2026.844739 Braz J Anesthesiol, vol.76, n3, 844739, 2026

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Abstract

Background

Nitrous Oxide (N₂O) is a potent greenhouse gas with significant environmental impact and is currently the leading ozone depleting substance in use. Despite its long-standing role in anesthetic practice, data on N₂O use and the environmental awareness of Brazilian anesthesiologists are scarce. This study aimed to describe patterns of N₂O use and assess the level of awareness among anesthesiologists regarding its environmental impact.

Methods

A nationwide cross-sectional survey was conducted among anesthesiologists in a private Brazilian hospital network. The questionnaire addressed the frequency of N₂O use in adult and pediatric anesthesia, knowledge of its environmental effects, and attitudes toward its continued availability.

Results

Of 1,238 eligible anesthesiologists, 941 completed the survey (response rate 76%). Overall, 59.3% (n = 558) reported never using N₂O in adult patients, while 14.5% (n = 136) reported frequent or constant use. In pediatric patients, 27.5% (n = 259) reported never using N₂O, and 38.9% (n = 366) reported frequent or constant use. Eighty percent (n = 753) indicated a reduction in N₂O use since the beginning of their careers, and 34.5% (n = 325) were unaware of its contribution to climate change. Age and years of professional experience were directly proportional to N₂O use in adults (p < 0.05), while awareness of its environmental impact was inversely associated with use in pediatric cases (p < 0.05).

Conclusion

The survey demonstrates a shift toward reduced N₂O use, particularly among younger anesthesiologists, although substantial use in adult practice remains. Persistent knowledge gaps highlight the importance of targeted education and policy interventions to mitigate environmental impact.

Keywords

Anestesiologists; Climate change; General anesthesia; Nitrous oxide N₂O; Occupational exposure

Resumo

Introdução

O óxido nitroso (N₂O) é um potente gás de efeito estufa com impacto ambiental significativo e atualmente é a principal substância destruidora da camada de ozônio ainda em uso. Apesar de seu papel consolidado na prática anestésica, há escassez de dados sobre o uso de N₂O e sobre a conscientização ambiental dos anestesiologistas brasileiros. Este estudo teve como objetivo descrever os padrões de uso de N₂O e avaliar o nível de conscientização dos anestesiologistas em relação ao seu impacto ambiental.

Métodos

Foi realizado um levantamento transversal nacional entre anestesiologistas de uma rede privada de hospitais brasileiros. O questionário abordou a frequência de uso de N₂O em anestesia de adultos e pediátrica, o conhecimento sobre seus efeitos ambientais e as atitudes em relação à sua disponibilidade contínua.

Resultados

Dos 1.238 anestesiologistas elegíveis, 941 completaram o questionário (taxa de resposta de 76%). No total, 59,3% (n = 558) relataram nunca utilizar N₂O em pacientes adultos, enquanto 14,5% (n = 136) relataram uso frequente ou constante. Em pacientes pediátricos, 27,5% (n = 259) relataram nunca utilizar N₂O e 38,9% (n = 366) relataram uso frequente ou constante. Oitenta por cento (n = 753) indicaram redução no uso de N₂O desde o início de suas carreiras, e 34,5% (n = 325) desconheciam sua contribuição para as mudanças climáticas. Idade e anos de experiência profissional foram diretamente proporcionais ao uso de N₂O em adultos (p < 0,05), enquanto a conscientização sobre seu impacto ambiental esteve inversamente associada ao uso em casos pediátricos (p < 0,05).

Conclusão

O levantamento demonstra uma tendência de redução no uso de N₂O, particularmente entre anestesiologistas mais jovens, embora o uso substancial em adultos ainda persista. Lacunas persistentes de conhecimento destacam a importância de educação direcionada e de intervenções em políticas para mitigar o impacto ambiental.

Palavras-chave

Anestesiologistas; Mudanças climáticas; Anestesia geral; Óxido nitroso N₂O; Exposição ocupacional

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Submetido em:
23/06/2025

Aceito em:
14/02/2026