RESUMEN
BACKGROUND: Although minimally invasive distal pancreatectomy (MIDP) is considered a standard approach it still presents a non-negligible rate of conversion to open that is mainly related to some difficulty factors, as obesity. The aim of this study is to analyze the preoperative factors associated with conversion in obese patients with MIDP. METHODS: In this multicenter study, all obese patients who underwent MIDP at 18 international expert centers were included. The preoperative factors associated with conversion to open surgery were analyzed. RESULTS: Out of 436 patients, 91 (20.9%) underwent conversion to open, presenting higher blood loss, longer operative time and similar rate of major complications. Twenty (22%) patients received emergent conversion. At univariate analysis, the type of approach, radiological invasion of adjacent organs, preoperative enlarged lymphnodes and ASA ≥ III were significantly associated with conversion to open. At multivariate analysis, robotic approach showed a significantly lower conversion rate (14.6 % vs 27.3%, OR = 2.380, p = 0.001). ASA ≥ III (OR = 2.391, p = 0.002) and preoperative enlarged lymphnodes (OR = 3.836, p = 0.003) were also independently associated with conversion. CONCLUSION: Conversion rate is significantly lower in patients undergoing robotic approach. Radiological enlarged lymphnodes and ASA ≥ III are also associated with conversion to open. Conversion is associated with poorer perioperative outcomes, especially in case of intraoperative hemorrhage.
RESUMEN
In this paper, we propose a method to model radiofrequency electrosurgery to capture the phenomena at higher temperatures and present the methods for parameter estimation. Experimental data taken from our surgical trials performed on in vivo porcine liver show that a non-Fourier Maxwell-Cattaneo-type model can be suitable for this application when used in combination with an Arrhenius-type model that approximates the energy dissipation in physical and chemical reactions. The resulting model structure has the advantage of higher accuracy than existing ones, while reducing the computation time required.