Efeitos da estimulação elétrica nervosa transcutânea de baixa e alta frequência em pacientes com dor oncológica sob cuidados paliativos que fazem uso crônico de morfina: ensaio clínico randomizado

Abstract

Introduction: The treatment of cancer patients aims not only to reduce tumors but also to improve their quality of life, both during treatment and for individuals in Palliative Care (PC). One of the most common symptoms in individuals with cancer is cancer pain, which is present in 50% to 70% of patients at the beginning of treatment and in up to 90% of those in advanced stages, directly impacting their quality of life. Given its subjective and multifaceted nature, cancer pain is the result of physical, cognitive, psychological and social aspects, making its assessment complex and its control and treatment challenging. Electrotherapy, through Transcutaneous Electrical Nerve Stimulation (TENS), is a non-invasive, simple, safe and low-cost physiotherapeutic resource that is highly effective in reducing pain and analgesic consumption. Objective: evaluate the effect of high-frequency and low-frequency TENS in controlling cancer pain in PC patients using morphine specifically. Methodology: This is a planned clinical trial, which involves data collection at four moments: pre-intervention, immediately after, one hour after and 24 hours after intervention. Participants were divided into two groups: GALTA, which received high-frequency TENS and GBAIXA, which received low-frequency TENS. Results: A total of 43 participants were included in the study, 21 from the high-frequency TENS group and 22 from the low-frequency TENS groupThe results showed a prevalence of females, with a mean age of 51 years. Regarding pain intensity scores, it was observed that GALTA presented lower pain intensities when compared to GBAIXA. Regarding the Brief Pain Inventory domains, both GALTA and Gbaixa presented statistical significance in the domain of pain intensity at the precise moment of assessment and in the pain relief domain, while in the pain impact domain, GALTA presented significance in the items relationship with other people, sleep and pleasure of living. While GBAIXA presented significance only in the item relationship with other people. The morphine dosage was quantified before and after 24 hours of the intervention in both groups, and it was observed that the patients who presented a reduction in the morphine dosage were in GALTA. Regarding the analysis of the prescription of adjuvant medications, it was observed the maintenance, addition or withdrawal of the prescribed medications, before and after the intervention and no evidence was observed of an association between these two variables. Similarly, the analysis of the number of morphine rescues/day in the pre- and post-intervention periods showed no significant difference in either group. Conclusion: Thus, TENS proved to be effective both for controlling pain intensity and for improving the perception of pain interference in its various aspects, highlighting the clear superiority of high-frequency TENS for patients on chronic morphine use.