ORIGINAL
Introdução: O manejo terapêutico adequado da dor neuropática continua sendo um desafio nos dias de hoje; portanto; novas terapias clínicas e cirúrgicas estão constantemente sendo desenvolvidas e visando um nível suficiente de alívio da dor que permita uma qualidade de vida aceitável para o paciente. No entanto, embora o manejo clínico e farmacológico da dor neuropática tenha melhorado significativamente, até 8% dos pacientes permanecem sem resposta terapêutica adequada, dos quais 74% têm dor moderada a intensa. Apesar do grande número de descrições científicas sobre o tratamento com pregabalina e tramadol, não há elucidação completa desses dois métodos terapêuticos quando comparados diretamente. Objetivo: avaliar os efeitos do uso do tramadol e da pregabalina no tratamento da dor neuropática periférica induzida mecanicamente em modelo animal. Métodos: Foram utilizados 18 machos da linhagem Wistar distribuídos em 5 grupos: dois grupos teste (pregabalina e cloridrato de tramadol); dois grupos controle (pregabalina e cloridrato de tramadol) e um grupo piloto cirúrgico. Foi realizada a compressão do nervo ciático através da técnica de compressão de nervo periférico. Após 4 dias, os animais que apresentaram alodínia foram submetidos à injeção intraperitoneal de cloridrato de tramadol e à gavagem oral de pregabalina, no 4º e 6º dia pós-operatório. Todos os animais foram acompanhados por 3 dias para avaliação da alodínia pelo “ascending stimulus method”. Resultados: Ao analisar os momentos pré-tratamento; o primeiro dia de tratamento e o terceiro dia de tratamento; segundo o tipo de medicamento utilizado, não é observado diferença entre os grupos (p > 0,05). Os resultados intragrupo entre a amostra que usou pregabalina, apenas os momentos pré-tratamento (média=2,40) e terceiro dia de tratamento (média=242,0) se mostraram diferentes (p=0,014). Entre os animais que usaram tramadol, encontrou diferença entre os momentos pré-tratamento (média=3,60) com o primeiro dia de tratamento (média=300,0) (p<0,001); e entre pré-tratamento (média=2,40) e terceiro dia de tratamento (média=242,0) (p=0,015). Conclusão: Em nosso estudo, verificamos que tanto a pregabalina como o cloridrato de tramadol são fármacos eficazes na diminuição álgica nesta entidade patológica. No entanto, na comparação entre eles não foi possível obter dados estatísticos significantes, dado as limitações do projeto, sendo necessários estudos futuros a fim de melhor compreender o fármaco mais eficaz.
Introduction: proper therapeutic management of neuropathic pain remains a challenge nowadays, thus new clinical and surgical therapies are constantly being developed and aiming for a sufficient level of pain relief that allows an acceptable quality of life for the patient. However, although the clinical and pharmacological management of neuropathic pain have improved significantly, up to 8% of the patients remain without adequate therapeutic response, of which 74% have moderate to severe pain. Despite the large number of scientific descriptions regarding treatment with pregabalin and tramadol, there is no complete elucidation of these two therapeutic methods when directly compared. Objective: to evaluate the effects of tramadol and pregabalin for treatment of peripheral neuropathic pain mechanically induced in animal model. Methods: eighteen Wistar strain males were divided into 5 groups: two test groups (pregabalin and tramadol), two control groups (pregabalin and tramadol) and a surgical pilot group. Sciatic nerve compression was performed using the Peripheral Nerve Compression technique. After 4 days, the animals that presented with allodynia were submitted to intraperitoneal tramadol injection and oral gavage of pregabalin, on the 4th and 6th postoperative day. Every animal had been followed up during 3 days for allodynia assessment by the “ascending stimulus method”. Results: when analyzing the pre-treatment moments, the first day of treatment, and the third day of treatment, according to the type of medication, no difference was observed between the groups (p > 0.05). The results within the sample that used pregabalin, only the pre-treatment (mean=2.40) and the third day of treatment (mean=242.0) were different (p=0.014). Within the animals that used tramadol, they differed between pre-treatment (mean=3.60) and the first day of treatment (mean=300.0) (p < 0.001); and between pre-treatment (mean=2.40) and the third day of treatment (mean=242.0) (p=0.015). Conclusion: In our study, we figured that both pregabalin and tramadol are effective drugs to reduce pain in this pathological entity. However, during the comparison between these two drugs, it was not possible to obtain significant statistical data, given the limitations of this project, and further studies are needed in order to better understand which one is the most effective drug.
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1 Medical Student, Pontifical Catholic University of São Paulo, Sorocaba (SP), Brazil.
2 MSc, Doctorate student in Health Sciences, Postgraduation Health Sciences Department, Instituto de Assistência Médica ao Servidor Público Estadual; University Cidade de São Paulo, São Paulo (SP), Brazil.
3 Veterinarian, Pontifical Catholic University of São Paulo, Sorocaba (SP), Brazil.
4 MD, PhD, Rheumatologist, Rheumatology Department, Pontifical Catholic University of São Paulo, Sorocaba (SP), Brazil.
5 MD, PhD, Neurosurgeon, Neurology Department, Pontifical Catholic University of São Paulo, Sorocaba (SP), Brazil.
Received Feb 27, 2023
Corrected Mar 2, 2023
Accepted Mar 7, 2023
