Curva de aprendizado em cirurgia aórtica videolaparoscópica: estudo experimental em porcos

Comparative angiotomographic study of swine vascular anatomy: contributions to research and training models in vascular and endovascular surgery

Background

Medium and large animal models allow researchers to evaluate the efficacy and safety of cardiovascular procedures in systems that resemble human anatomy and can be used to simulate scenarios for training purposes. Although porcine models have been used extensively, many physiological and anatomical features remain unknown or only superficially described.

Objectives

To describe the normal porcine vascular anatomy on computed tomography scans, compare it to human vascular anatomy, and discuss the application of porcine models for open and endovascular procedures.

Methods

Three male Landrace pigs underwent computed tomography. The vascular anatomy of the neck, thorax, abdomen, and limbs was analyzed and described; relevant similarities and differences between porcine and human vascular anatomies and the implications for vascular procedures in pigs are highlighted.

Results

The carotid territory, aortic arch, and terminal aorta branches all show marked differences in pigs compared to their human counterparts. Compressions of both left renal and common iliac veins were detected, analogous to those seen in human Nutcracker and May-Thurner syndromes. Vascular measurements (diameters, lengths, and angles) of several different porcine territories are presented.

Conclusions

The data presented should be useful for planning preclinical trials and basic research and for refining surgical training using porcine models in vascular fields.

Arteriovenous anastomosis learning curve using low cost simulator

Background

In order to reduce difficulties with learning surgical techniques, supplementary tools for training were developed. This paper describes the learning curve followed by student volunteer research subjects who used an alternative model for practicing vascular anastomosis.

Objectives

To evaluate the vascular anastomosis technique learning curve and development of manual skills using a low-cost experimental model.

Methods

Experimental and prospective study using end-to-side vascular anastomosis in latex balloons over five successive phases, initiated after theoretical and practical guidance given by experienced vascular surgeon. The study subjects were six undergraduate medical students from Universidade Federal da Paraíba (UFPB), João Pessoa, PB, Brazil, in their third to fifth years of the course. Cluster analysis was used to interpret the data collected on the quality of anastomoses and the time taken.

Results

The time taken to perform anastomosis reduced for all students, with statistical differences from phase 1 compared to phases 4 and 5. There was also a trend to increasing scores on the quality index as the phases progressed. However, no statistical differences were detected using the Friedman test, which is appropriate for data measured with ordinal levels (quality was assessed on a scale of 1 to 5).

Conclusions

It was found that the training model used was effective for increasing learning of this technique. It is believed that future studies with larger samples or a higher number of phases could demonstrate both reduced time and improved quality of the anastomoses performed with statistical significance.