Brazilian Journal of Anesthesiology
Brazilian Journal of Anesthesiology
Review Article

A comparison of ramping position and sniffing position during endotracheal intubation: a systematic review and meta-analysis

Comparação entre a posição de rampa e posição olfativa durante intubação traqueal: revisão sistemática e meta-análise

Samuel Ern Hung Tsan, Ka Ting Ng, Jiaying Lau, Navian Lee, Viknaswaran, Chew Yin Wang

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Positioning during Endotracheal Intubation (ETI) is critical to ensure its success. We aimed to determine if the ramping position improved laryngeal exposure and first attempt success at intubation when compared to the sniffing position.

PubMed, EMBASE, and Cochrane CENTRAL databases were searched systematically from inception until January 2020. Our primary outcomes included laryngeal exposure as measured by Cormack-Lehane Grade 1 or 2 (CLG 1/2), CLG 3 or 4 (CLG 3/4) and first attempt success at intubation. Secondary outcomes were intubation time, use of airway adjuncts, ancillary manoeuvres and complications during ETI.

Seven studies met our inclusion criteria, of which 4 were RCTs and 3 were cohort studies. The meta-analysis was conducted by pooling the effect estimates for all 4 included RCTs (n = 632). There were no differences found between ramping and sniffing positions for odds of CLG 1/2, CLG 3/4, first attempt success at intubation, intubation time, use of ancillary airway manoeuvres and use of airway adjuncts, with evidence of high heterogeneity across studies. However, the ramping position in surgical patients is associated with increased likelihood of CLG 1/2 (OR = 2.05, 95% CI 1.26 to 3.32,p =  0.004) and lower likelihood of CLG 3/4 (OR = 0.49, 95% CI 0.30 to 0.79, p =  0.004), moderate quality of evidence.

Our meta-analysis demonstrated that the ramping position may benefit surgical patients undergoing ETI, by improving laryngeal exposure. Large-scale well-designed multicentre RCTs should be carried out to further elucidate the benefits of the ramping position in the surgical and intensive care unit patients.


Ramping position;  Sniffing position;  Endotracheal intubation;  Laryngeal exposure;  Intubation success


A posição do paciente durante a Intubação Traqueal (IT) é fundamental para o sucesso do procedimento. Nosso objetivo foi determinar se a posição de rampa melhorou a visualização laríngea e o êxito na primeira tentativa de intubação quando comparada à posição olfativa.

Os bancos de dados PubMed, EMBASE e Cochrane CENTRAL foram pesquisados de forma ​​sistemática a partir da data em que os bancos de dados foram estabelecidos até janeiro de 2020. Nossos desfechos primários incluíram a visualização laríngea avaliada como Cormack-Lehane Grau 1 ou 2 (CLG 1/2), Cormack-Lehane Grau 3 ou 4 (CLG 3/4) e o êxito na primeira tentativa de intubação. Os desfechos secundários foram o tempo de intubação, uso de dispositivos adjuvantes para manuseio de vias aéreas, manobras auxiliares e complicações durante a IT.

Sete estudos preencheram nossos critérios de inclusão, dos quais 4 eram Estudos Clínicos Randomizados (ECR) e 3 eram estudos de coorte. A meta-análise foi conduzida combinando as estimativas de efeito para todos os 4 ECR incluídos (n = 632). Não foram encontradas diferenças entre as posições de rampa e olfativa para razão de chances de CLG 1/2, CLG 3/4, sucesso na primeira tentativa de intubação, tempo de intubação, uso de manobras auxiliares das vias aéreas e uso de dispositivos adjuvantes de vias aéreas, havendo evidência de alta heterogeneidade nos estudos. No entanto, a posição de rampa em pacientes cirúrgicos está associada com maior probabilidade de CLG 1/2 (OR = 2,05; 95% IC 1,26 a 3,32;p =  0,004) e menor probabilidade de CLG 3/4 (OR =  0,49; 95% IC 0,30 a 0,79; p =  0,004), com qualidade moderada de evidência.

Nossa meta-análise demonstrou que a posição de rampa pode beneficiar pacientes cirúrgicos submetidos a IT, melhorando a visualização laríngea. ECR multicêntricos bem projetados com amostras grandes devem ser realizados para esclarecer ainda mais os benefícios da posição de rampa nos pacientes cirúrgicos e na unidade de terapia intensiva.


Posição de rampa;  Posição olfativa;  Intubação traqueal;  Visualização laríngea;  Êxito na intubação


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