Brazilian Journal of Anesthesiology
Brazilian Journal of Anesthesiology
Scientific Article

Short term olfactory memory and olfactory function after inhalation anesthetic agents: a randomized clinical trial

Memória olfativa de curta duração e função olfativa após anestésicos inalatórios: estudo clínico randomizado

Huseyin Sari, Yavuz Atar, Tarkan Mingir, Tolgar Lutfi Kumral, Muhammed Fatih Akgun, Esmail Abdulahi Ahmed, Imran Aydogdu, Ziya Salturk, Guler Berkiten, Yavuz Uyar

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Background and objectives
This clinical trial aimed to evaluate the effects of two different inhalation anesthetic agents on postoperative olfactory memory and olfactory function in patients who underwent micro laryngeal surgery.

This randomized prospective controlled study consisted of 102 consecutive patients with a voice disorder. The patients underwent micro laryngeal surgery for voice disorders under general anesthesia. Patients who did not meet inclusion criteria and/or declined to participate (n = 34) were excluded from the study. Patients were divided into two groups. Four patients from Group 1 and four patients from Group 2 were lost to follow-up. Group 1 (n = 30) received sevoflurane, and Group 2 (n = 30) received desflurane during anesthesia. We compared the results by performing the pre-op and post-op Connecticut Chemosensory Clinical Research Center Olfactory test.

Thirty-three patients (55%) were male and 27 (45%) were female. The mean age was 48.18 ± 13.88 years (range: 19‒70 years). Preoperative and postoperative olfactory functions did not show a significant difference within the groups postoperatively (p > 0.05). Preoperative and postoperative olfactory memory showed a significant decrease 3 hours after the surgery (p < 0.05).

Olfactory functions and memory were not affected by desflurane in the early postoperative period. Although sevoflurane did not affect olfactory functions, it had a temporary negative effect on olfactory memory in the early postoperative period.


Olfactory memoryInhalation anesthesiaDesfluraneSevoflurane


Introdução e objetivos
O estudo avaliou o efeito pós-operatório de dois agentes anestésicos inalatórios distinto na memória olfativa de curta duração e na função olfativa em pacientes submetidos à microcirurgia de laringe.

O estudo prospectivo controlado randomizado avaliou, consecutivamente, 102 pacientes com alteração vocal submetidos à microcirurgia de laringe sob anestesia geral. Trinta e quatro pacientes não obedeceram aos critérios de inclusão e/ou não aceitaram participar do estudo e foram excluídos. Os pacientes foram divididos em dois grupos. Quatro pacientes do Grupo 1 e quatro do Grupo 2 foram perdidos durante o seguimento. O Grupo 1 (n = 30) recebeu sevoflurano e o Grupo 2 (n = 30) desflurano durante a anestesia. Comparamos resultados pré e pós-operatórios de memória olfativa e funções olfativas, realizando o Connecticut Chemosensory Clinical Research Center Olfactory test.

Foram incluídos um total de 33 (55%) homens e 27 (45%) mulheres. A idade média foi 48,18 ± 13,88 anos (variação: 19‒70 anos). As funções olfativas pré e pós-operatórias não apresentaram diferença estatisticamente significante dentro dos grupos no pós-operatório (p > 0,05). A memória olfativa pré e pós-operatória não mostrou diminuição estatisticamente significante quando avaliada três horas após a cirurgia (p <  0,05).

Memória e funções olfativas não foram alteradas pelo desflurano no pós-operatório imediato. Embora o sevoflurano não tenha alterado as funções olfativas, causou efeito temporário negativo na memória olfativa no pós-operatório imediato.


Memória olfativaAnestesia inalatóriaDesfluranoSevoflurano


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