O efeito do uso da prótese sobre as variáveis hemodinâmicas e autonômicas cardíacas em amputados traumáticos de membro inferior

Abstract

The traumatic lower limb amputees have higher morbidity and mortality from cardiovascular disease compared to the general population. However, the risk factors for this increased morbidity, as well as the pathophysiological mechanisms responsible are not well understood. The aim of this study was to test the hypothesis that the use of the prosthesis in transtibial amputees traumatic increases blood pressure (BP) and heart rate (HR) and decreased heart rate variability (HRV) in the supine posture (PS) and standing position (PO). 20 individuals, males, 10 with unilateral transtibial amputations and traumatic amputations 10 individuals without (controls) were evaluated. The registration of the FC, for the calculation of measures of HRV was performed by means of the heart rate Polar ® RS300CX model and BP monitor was checked by auscultation and oscillometry. The groups were evaluated at rest, the PS and PO, being amputees undergoing the protocol with and without the prosthesis. For intragroup comparisons 2x2 ANOVA repeated measures and paired t tests were performed; and comparison groups was used for independent samples Student's t test. The amputee group, with or without the prosthesis, it was found that FC is larger compared to PO the PS (82.5 ± 11.1 vs. 66.8 ± 6.7 beats per minute respectively) and that when using the prosthesis HR was higher compared to unaided, (76.8 ± 9.0 vs. 72.5 ± 8.0 bpm respectively). Analyzing the autonomic variables of amputees in PO compared to PS, they had lower values of RR intervals (763.0 ± 100.3 vs. 911.0 ± 89.9, p <0.001), rMSSD (23.0 ± 14.0 vs. 37.7 ± 21.5, p = 0.001), pNN50 (5.9 ± 9.4 vs. 16.8 ± 18.6, p = 0.01) and HF (24.5 ± 15.0 vs. 42.8 ± 18.8, p = 0.02) and higher values of LF (77.1 ± 12.7 vs. 57.2 ± 18.8, p = 0.04) and LF / HF (5.9 ± 5.7 vs. 2.1 ± 1.7, p = 0.07). Regarding the use of prosthesis, lower values of RR intervals (814.6 ± 92.2 vs. 859.4 ± 92.2, p = 0.001) were observed, rMSSD (26.6 ± 14.8 vs. 34.2 ± 20.1, p = 0.002) and pNN50 (11.9 ± 8.9 vs. 13.7 ± 15.4, p = 0.005) compared to the unaided. Compared to the control group, HR amputees using prostheses was higher both in PS as in PO, whereas when the prosthesis was removed, this difference disappeared. We conclude that the use of the prosthesis alters hemodynamic variables by increasing HR and BP and autonomic variables by reduced HRV.