Fotobiomodulação na cicatrização de úlceras pós- amputações menores em pacientes com diabetes mellitus: ensaio clínico controlado

Abstract

Context: Diabetic foot ulcers are chronic ulcers, difficult to treat and are the main cause of limb amputations. After the first amputation, patients are at greater risk of a second amputation in a year. A potential application of low- power laser therapy is an adjunct to the treatment of post-amputation wounds in diabetics. However, there is a shortage of controlled clinical studies that demonstrate the efficacy of laser as an adjuvant in the treatment of post- amputation wounds in diabetics.Objective: To evaluate the action of laser photobiomodulation in the healing of ulcers after minor amputations in patients wi th DM. Method: The study was conducted with patients in ambulatory medical follow-up at a tertiary-level public hospital in the city of São Paulo after approval of the Research Ethics Committee (CAAE 53351716.5.0000.5511), and divided into two phases. Phase I: 16 patients were randomly divided into two groups. The conventional group consisted of cleaning the lesion with saline and primary coverage, and the photobiomodulation group consisted of conventional laser treatment with λ = 660nm, P = 108mW, A = 0.04cm2, I = 2.7W / cm2, H = 108J / cm2, t = 40s, E = 4.32J. The lesions were evaluated weekly by measuring the area, perimeter, temperature, pH and glycemia. Statistical analysis was performed using the Origin Pro 2017 software. The significance of all tests was  = 0.05. Phase II: Presentation of 12 reports of cases treated wi th laser in the same dosimetric parameters used in phase I. Results: Phase I: After 5 weeks there was no significant difference regarding area, perimeter, pH, temperature or blood glucose between groups. 100% of the patients in the photobiomodulation group presented granulation tissue, where as in the conventional group 0%, this difference being significant (p = 0.0014). By means of the ROC curve it was possible to establish the cut off of the appearance of granulation tissue, and the period of 4 weeks was obtained. Phase II: Up to 18 laser treatment sessions make the probability of ulcer closure increasing, but beyond 18 sessions the probability starts to decrease, becoming less than 40%. It was also possible to determine the glycemic limit for the success of photobiomodulation: up to 225mg / dL. Patients who had the ulcer closed will have a follow-up of 6 months and the others will continue the treatment until the total reduction of the area of the lesion is reached. Conclusion: The laser photobiomodulation in the parameters used accelerated the appearance of granulation tissue and provided healing of 100% of the lesion in 6 phase II patients. The study was also instrumental in defining the ideal number of sessions to maximize the chance of ulcer healing: 1x per week up to 18 weeks and wi th a more effective action in patients with capillary glycemia below 225mg / dl.