Pressurized Cadaver Model in Cardiothoracic Surgical Simulation

Assessment of a Perfusion and Ventilation Method for Detecting Lung and Liver Injury in a Cadaveric Model

Surgical simulation models have been developed using post-mortem human subjects (PMHS). These models involve the pressurization and ventilation of the PMHS to create a more realistic environment for training and the practice of surgical procedures. The overall objective of this study was to determine the feasibility of a previously developed surgical simulation model to detect soft tissue injuries during a ballistic impact to the torso. One of the main limitations of using PMHS for the assessment of soft tissue injuries in the field of injury biomechanics is the lack of physiological blood flow. To overcome this limitation, the assessment of the surgical simulation model for use in injury biomechanics applications was conducted based on data collected from behind armor blunt trauma (BABT) case studies. Documented injuries in real-world cases included anterior lung contusion, posterior lung contusion, and liver contusion. These real-world injuries were compared to those seen post-impact in the PMHS using pathological and histological techniques. Discussion of limitations and future work is presented.

Human Cadaveric Artificial Lung Tumor-Mimic Training Model

Introduction: An important phase in surgical training is gaining experience in real human anatomical situations. When a cadaver is available it may complement the various artificial practice models. However, it is often necessary to supplement the characteristics of the cadavers with a simulation of a tumor. Our objective was to develop an easy-to-create, realistic artificial tumor-mimic model for peripheral lung tumor resection practice.

Methods: In our work we injected barium sulphate enriched silicone suspension into 10 isolated, non-fixed lungs of human cadavers, through the puncture of the visceral pleura. Four lesions–apical, hilar and two peripheral–were created in each of ten specimens. After fixation CT scans were obtained and analyzed. The implanted tumor-mimics were examined after anatomical preparation and slicing. Also performed CT-guided percutaneous puncture was also performed to create the lesions in situ in two lungs of human cadavers.

Results: Analyzing the CT data of 10 isolated lungs, out of 40 lesions, 34 were nodular (85.0%) and in the nodular group five were spiculated (12.5%). Satellite lesions were formed in two cases (5.0%). Relevant outflow into vessels or airway occurred in five lesions (12.5%). Reaching the surface of the lung occured in 11 lesions (27.5%). The tumor-mimics were elastic and adhered well to the surrounding tissue. The two lesions, implanted via percutaneous puncture, both were nodular and one also showed lobulated features.

Conclusion: Our artificial tumor-mimics were easy to create, varied in shape and size, and with percutaneous implantation the lesions provide a model for teaching every step of a surgical procedure.

Nikaidoh Procedure: The Wet Lab Trainee's Perspective

Congenital heart surgeons' training is complex and challenging. The learning curve is long and the increasing complexity of pathologies is demanding. In order to develop adequate surgical-skill competencies, "in vivo" and simulation-based practicing are paramount. Simulation can be performed either on a computer screen or animal hearts and prosthetic models. In this article, we illustrate a porcine Wet Lab simulation for the Nikaidoh operation to point out its potential advantage to learn complex congenital surgery procedures.

Cadaveric Simulation Training in Cardiothoracic Surgery: A Systematic Review

Simulation training has become increasingly relevant in the educational curriculum of surgical trainees. The types of simulation models used, goals of simulation training, and an objective assessment of its utility and effectiveness are highly variable. The role and effectiveness of cadaveric simulation in cardiothoracic surgical training has not been well established. The objective of this study was to evaluate the current medical literature available on the utility and the effectiveness of cadaveric simulation in cardiothoracic surgical residency training. A literature search was performed using PubMed, Cochrane Library, Embase, Scopus, and CINAHL from inception to February 2019. Of the 362 citations obtained, 23 articles were identified and retrieved for full review, yielding ten eligible articles that were included for analysis. One additional study was identified and included in the analysis. Extraction of data from the selected articles was performed using predetermined data fields, including study design, study participants, simulation task, performance metrics, and costs. Most of these studies were only descriptive of a cadaveric or perfused cadaveric simulation model that could be used to augment clinical operative training in cardiothoracic surgery. There is a paucity of evidence in the literature that specifically evaluates the utility and the efficacy of cadavers in cardiothoracic surgery training. Of the few studies that have been published in the literature, cadaveric simulation does seem to have a role in cardiothoracic surgery training beyond simply learning basic skills. Additional research in this area is needed.

A novel model for minimally invasive left ventricular assist device implantation training

Background: Significant advances in minimally invasive implantation of mechanical circulatory support devices have been made. These approaches are technically challenging and associated with a learning curve. Simulation and training opportunities in these techniques are limited. We developed a high-fidelity novel model for minimally invasive left ventricular assist device implantation.Material and methods: Using a modified inanimate simulator (LSI SOLUTIONS^®) and an animal tissue model, a hybrid simulator was created, with a porcine ex vivo heart secured within the inanimate simulator in the normal anatomic position. Key components of the minimally invasive left ventricular assist device implantation were performed, including left ventricular apical coring, attachment of the apical ring, attachment of the assist device, and creation of the aortic-outflow graft anastomosis.Results: A novel composite inanimate and tissue model for minimally invasive left ventricular assist device implantation was successfully developed. These simulation techniques were reproducible, and the model demonstrated ability to successfully simulate key components of the procedure.Conclusions: This high-fidelity, reproducible hybrid model allows for crucial components of minimally invasive LVAD implantation to be performed. This model has the potential to be used as an adjunct to surgical training, providing a safe and controlled learning environment for trainees to acquire skills in minimally invasive LVAD implantation.

Systematic review of surgical training on reperfused human cadavers

BACKGROUND

The role of reperfused human cadavers in surgical training has not been established.

METHODS

Reports describing reperfused human cadaver models in terms of simulated surgeries, the use of tools to assess technical competency and skills transfer to patients, cadaver status and reperfusion techniques were included.

RESULTS

Thirty-five reports were included. Most participants practised vascular (n = 27), flap (n = 6) and trauma (n = 4) procedures. Training progression was evaluated objectively in only two studies. In two publications, flap techniques were practised on cadavers and repeated successfully in patients. Eighteen studies employed whole bodies. Fresh and embalmed cadavers were both used in 17 publications. Most embalmed cadavers were formalin-fixed (n = 10), resulting in stiffness. Few trainings were offered on soft Thiel-embalmed cadavers (n = 5). Only arteries were reperfused in 20 studies, while in 13 publications, the arteries and veins were filled. Arteries and/or veins were mostly pressurized (n = 21) and arterial flow was generated in 14 studies.

CONCLUSIONS

Various reperfused human cadaver models exist, enabling practise of mainly vascular procedures. Preservation method determines the level of simulation fidelity. Thorough evaluation of these models as surgical training tools and transfer effectiveness is still lacking.

Simulation and Deliberate Practice in a Porcine Model for Congenital Heart Surgery Training

BACKGROUND

Surgeons in training for congenital cardiac surgery face considerable challenges owing to procedure complexity, closely scrutinized outcomes, and a steep learning curve. Simulation methods have been initiated in other surgical specialties, but have yet to be established for congenital cardiac surgery trainees. The purpose of this study was to assess high-fidelity simulation as a method to train and improve skills of resident trainees learning critical components of index congenital cardiac surgical procedures.

METHODS

Using 5 neonatal piglets over a period of 2.5 days, the following procedures were simulated: Norwood procedure, arterial switch operation, neonatal Ross procedure, tetralogy of Fallot repair, systemic to pulmonary artery shunt procedures, transmediastinal coarctation repair, atrial septal defect repair, ventricular septal defect repair, and right ventricular to pulmonary artery conduit. Anastomoses were tested with saline, all procedures were timed and video recorded, and resident trainee techniques and skills were critiqued by the instructor.

RESULTS

All aspects of the procedures were simulated with minimal modifications. Anastomoses were tested, and the procedure successfully replicated without the pressures of operative time. Operative techniques involving suture placement in neonatal tissue, depth perception, and patch size estimation were corrected in real time, resulting in observed improvement of surgical skills. Video review allowed for further pedagogic value through examination and documentation of competency.

CONCLUSIONS

This neonatal porcine simulation model allows surgical trainees in congenital heart surgery to make and correct mistakes in a safe and controlled learning environment without compromising patient safety, thereby fostering surgeon competence and confidence.