Electrical Impedance Spectroscopy to easily assess structural changes in dominant versus auxiliary upper arms due to pathophysiological events

The resistive component of the bioimpedance was non invasively assessed in both right and left forearms of 11 healthy female and 9 males (28.4 ± 1.4 years; 63.8 ± 11.8 kg; 167.4 ± 7.5 cm) all of which were right-handed. A homemade electrical impedance spectroscopy device which implemented the AD 5933 electronic board from Analog Devices Inc., USA, was utilized, and the bipolar modality of bioimpedance assessment was chosen using two disposable ECG surface electrodes placed in each end of the biceps brachial muscles while subject were comfortably sitting. Forearms resistance was acquired at sweeping frequencies steps of 15, 30, 45, 60 and 75 KHz. Results showed a significantly lower man value of resistance in right versus left forearms (- 27.4 Ω, P<0.05), or about -4%, at the frequency of 15 KHz. Even though there was a progressive reduction, this right versus left forearm resistance difference persisted as statistically significant up to the frequency of 45 KHz. It was concluded that the risk of some mistakes do exists when lymphedema may occur in one arm and electrical impedance spectroscopy was utilized to monitoring in that arm the water volume trend in comparison with the other side arm since these results underline in the main forearm a largely low value of the resistance than in the auxiliary one, even in healthy subjects. So, care must be taken when the electrical impedance spectroscopy was adopted in these clinical assessments. ### Competing Interest Statement The authors have declared no competing interest.