RESUMO
On site monitoring of engine oil is required. The features of a shear horizontal surface acoustic wave (SH-SAW) sensor include simultaneous detection of mechanical and electrical properties of liquids (such as viscosity, relative permittivity, and conductivity) and loaded mass on the sensor surface. In this paper, the used engine oil extracted from a motorbike was measured using the SH-SAW sensor. The degradation factors of the used engine oil were experimentally discussed. Especially, the influences of the particles in the engine oil, heating effect, and water contained in the engine oil were considered by comparing the differences between new and used engine oils. The results indicate that the influence of the water contained in the engine oil is the primary cause of the degradation of the used engine oil.
RESUMO
Background: The usefulness of closed incision negative pressure wound therapy (ciNPWT) has been well documented in many surgical sites, except for the donor site of the deep inferior epigastric artery perforator (DIEP) flap. The aim of this study was to evaluate the effect of ciNPWT on microsurgical breast reconstruction using a DIEP flap. Methods: Fifty-six cases of breast reconstruction with DIEP flap were included and divided into two groups based on post-surgical wound management: the ciNPWT group received ciNPWT at the donor site, while the conventional group received conventional wound management. The primary outcomes were the incidence of seroma, wound dehiscence, and surgical site infection, and secondary outcomes were the time to drain removal and amount of drainage. The breast reconstruction risk assessment (BRA) score was used to evaluate the comprehensive risk in each case. Results: Among the patient and surgical characteristics, only the BRA score (P=0.02) and the time to elevate the flap (P=0.02) were significantly higher and longer in the ciNPWT group, respectively. The incidence of seroma, dehiscence, and wound infection showed no significant difference between the two groups. In the subgroup analysis of patients with body mass index ≥ 25, the primary outcomes did not differ, while the secondary outcomes were significantly lower in the ciNPWT group (drainage volume, P = 0.04; time to drain removal, P = 0.04). Conclusion: ciNPWT can potentially reduce the incidence of donor site complications of DIEP flaps, especially if the comprehensive risk for post-surgical complications is considered.
RESUMO
The internal mammary vessels (IMA/Vs) have been used as the first-choice recipient vessels for microsurgical anastomosis and flap inset in autologous breast reconstruction owing to their ease of access and use compared with the thoracodorsal vessels (TDA/Vs). Herein, we report two cases of deep inferior epigastric perforator flap breast reconstructions in which the recipient internal mammary vein (IMV) was lacking. In the first case, a 50-year-old patient underwent delayed two-stage reconstruction, and in the second, a 45-year-old patient underwent delayed reconstruction because of capsular contracture following breast implant reconstruction. Neither patient received preoperative radiation therapy. During IMA/V preparation, we could not find the internal mammary vein (IMV) around the internal mammary artery (IMA) despite careful dissection. No internal mammary lymph node adenopathy and vascular encasement from metastasis were noted. Intraoperative indocyanine green angiography revealed absence of IMV, which was presumed to be congenital. Therefore, microsurgical anastomosis was performed to connect the deep inferior epigastric vessels to the thoracodorsal vessel. The postoperative course was uneventful in both cases. Although many anatomical studies have revealed different locations, diameters, branching patterns, and perforators of the IMA/V, absent IMV has been reported very rarely. In autologous breast reconstruction, plastic surgeons should be prepared for the possibility of the absence of IMV.