• mastectomy
• breast cancer
• bitch
• Harmonic Focus®
• oxidative stress
• Bap tests
• d-ROMs test

Objective: comparative evaluation of surgical insults using Harmonic® technology during mastectomy of the bitch compared to the classic technique, considering the oxidative stress responce to the two different procedures.
Materials and methods: we recruited for the study eleven bitches who underwent the surgery of monolateral mastectomy, and three of these performed on both files at different moments. These subjects were divided into two groups, one of which was used the Harmonic Focus®. For each patient we made 3 venous blood samples (3ml) at the following times: T0 = pre-induction; T1 = at the end of surgery; T2 = one hour after the end of surgery. The samples were placed in serum-tubes and centrifuged (4000 rpm for 3 minutes) and frozen. We, finally, evaluated some parameters of oxidative stress, through the use of BAP test and d-ROMs test.
Results: a statistically significant difference (p <0.05) was found between the BAP values in the classic technique compared to the one in which Harmonic® technology was used, with higher antioxidant values in the second group. There where no differences in the BAP values at the different times of blood samples and d-ROMs for any of the factors considered, “time”, “technique” and “patient”. The duration of the surgery was lower in the ultrasound group, with an average of 30,7 minutes for the classical technique and 23,6 for the Focus® system. The surgical time factor was significantly correlated (p <0.05) with the BAP value.
Discussions: the results just described may indicate a greater consumption of antioxidants caused by surgical insults during mastectomy with classic technique. Antioxidant capacity in serum of bitches in question has decreased statistically more by the use of classic technique. This higher consumption, by combating the excessive formation of oxygen-reactive species, helps maintain the values of d-ROMs, and therefore OSI, within a narrow range over the time period under consideration. BAP, significantly decreased with the increasing of the duration of surgery, can suggest that, regardless of technique, the antioxidant capacity decreases as the time of operation increases. Thus, we can hypothesize that the intervention time and reduced blood loss have contributed to the least oxidative response in patients undergoing mastectomy with Harmonic®.
Conclusions: in classical technique there is a statistically greater decrese in BAP which is consumed due to a more substantial free radical production due to longer surgery times than the group undergoing mastectomy using Harmonic® technology.