The American Journal of Surgery (2015) 210, 179-187
Surgical Education
Perfused fresh cadavers: method for application to surgical simulation Joseph N. Carey, M.D.a,*, Michael Minneti, B.S., R.R.T.b, Hyuma A. Leland, M.D.a, Demetrios Demetriades, M.D., Ph.D.c, Peep Talving, M.D., Ph.D.c a
Division of Plastic and Reconstructive Surgery, Keck School of Medicine, University of Southern California, 1500 San Pablo Street, Los Angeles, CA 90033, USA; bFresh Tissue Dissection Program, University of Southern California Surgical Skills Simulation and Education Center, Los Angeles, CA, USA; cDivision of Acute Care Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
KEYWORDS: Education; Anatomy; Simulation; Cadaver; Surgery
Abstract BACKGROUND: Cadaveric dissection is the gold standard for surgical simulation because it demonstrates authentic anatomy and tissue handling. We present a perfusion technique that restores blood flow and pressure in the fresh human cadaveric model. METHODS: The femoral vessels were cannulated and perfused using a vortex centrifugal pump and a novel perfusate. The trachea was intubated and mechanically ventilated. Tissue perfusion was evaluated by direct inspection, intravascular pressure monitoring, and indocyanine green angiography. A cost analysis and survey results for 969 trainees is presented. RESULTS: A mean arterial pressure of 80 mm Hg and venous pressure of 15 mm Hg were established, resulting in dermal and microvascular perfusion. Successful pulmonary ventilation was achieved. This model has been applied to 122 cadaveric specimens over 12 months in a variety of surgical subspecialties and training levels. Total cost for establishing the perfused model was $1,262.55. Trainee confidence after use of the model increased from 2.85 to 4.20 (P , .00). CONCLUSIONS: Perfusion of fresh cadavers replicates human tissue handling, vascular anatomy, and dissection. The perfused human cadaver increases the authenticity of surgical simulation and is applicable to procedure-based specialties. Ó 2015 Elsevier Inc. All rights reserved.
Acquisition of the skill set to become a surgeon requires practice in the same manner that one acquires the skill to become an athlete, an artist, a musician, or pilot. Knowledge of the equipment and instruments, in addition to The authors declare no conflicts of interest. * Corresponding author. Tel.: 11-323-442-7920; fax: 11-323-4425872. E-mail address:
[email protected] Manuscript received March 18, 2014; revised manuscript October 11, 2014 0002-9610/$ - see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.amjsurg.2014.10.027
experience with procedures, is the very basics of the process by which one becomes a competent surgeon. Decreases in US surgical resident clinical training hours have resulted in the need for supplementation of resident education with surgical simulation.1–4 Many models of simulation exist, including animals, inanimate body molds, and computer-based simulators. Current evidence demonstrates the utility of simulators in advancing specific surgical skills and techniques.5–11 Historically, fresh human cadavers were used for the purpose of simulating surgery
180 and learning anatomy. This technique is still used, and its benefits to surgical training have been reported in vascular surgery, plastic surgery, and gynecology.12–17 Despite the obvious benefits of fresh tissue dissection, all past applications have lacked physiologic parameters of blood flow and pressure. Successful reconstitution of cadaveric circulation has been accomplished and shown to be effective in simulating vascular, neurosurgical, and trauma surgical operations.18–21 The technical challenges of keeping blood flow and pressure in a fresh cadaver have been approached in several ways in these models, and elegant surgical simulations were demonstrated. Despite the success of these models, widespread use has been limited, secondary to a few specific challenges. The primary challenges that remain include optimal pressure and perfusate delivery systems, creation of a physiologic perfusate, demonstration of tissue perfusion at the skin level, and broad application to multiple training environments. We aimed to establish a reliable and repeatable method of procedural simulation that demonstrates physiologic parameters of surgery, in addition to the anatomical similarity already provided by the fresh cadaveric tissue. Herein we present our method of establishment of a pressurized model of cadaveric tissue, and demonstrate its initial application to surgical training in our institution.
Methods Logistics The Fresh Tissue Dissection Laboratory at the University of Southern California was established as a multidisciplinary educational program to allow physicians and medical students access to fresh tissue specimens for the purposes of anatomic and procedural teaching. The standard operating procedures were established and approved by the institutional review board in 2005 and revised in 2012. Procurement of all cadavers occurs according to the standard operating procedures and follows strict guidelines in adherence with California law, and University of Southern California Keck School of Medicine oversight.
Vascular access Cadavers admitted to the Fresh Tissue Dissection Laboratory are stored in holding beds maintained from 3.3 C to 5.6 C for 2 hours before a scheduled case. After the first hour at ambient temperature (20 C), the left femoral artery and vein are exposed via a 5-cm incision extending distally, beginning 2 finger breadths from the pubic tubercle. The profunda femoris is exposed and ligated with ‘‘0’’ silk. The femoral artery and vein are ligated, opened, and subsequently cannulated with 1/400 Sims connectors (Busse Hospital Disposables, Hauppauge, NY) adapted to accommodate vessel diameter (Fig. 1). The Sims connectors are secured inside the vessels with nylon ties. A
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Figure 1 The femoral artery and vein are cannulated resulting in retrograde flow into the arterial and anterograde flow into the venous systems.
5-cm segment of 1/400 ! 3/3200 inside diameter (ID) vinyl tubing is connected to the Sims connectors. For regional perfusion of the distal leg, the arterial Sims connector is directed distally into the femoral artery, and the femoral vein is opened but not cannulated.
Conditioning Before reperfusion, an oral-gastric tube is placed and opened to gravity. After cannulation of the vessels, a 2-m length of 1/400 ID tubing with a 3/800 ! 1/400 connector is attached to the 1/400 ID tubing from the Sims connector. The other end of this tubing is connected to the faucet and cold water is infused at 1 L/min. The arterial and venous systems are sequentially pressurized for 20-second intervals while light chest compressions, abdominal thrusts, and neck massage are performed on the depressurization cycle. The tubing is clamped when no further clot is seen exiting the venous system.
Fluid Arterial fluid consists of 18 L of water from the faucet, 800 mL of a nontoxic red-pigmented concentrate (premium tempera; Dick Blick Art Materials, Galesburg, IL), and 474 mL of .9% sodium chloride (NS). This fluid is kept in a 19-L reservoir and may be repeatedly filled during laboratory sessions by simply turning on the faucet and replacing the NS and red-pigment concentrate. The protocol can be modified for central line simulation, such that nontoxic bluepigmented concentrate (premium tempera; Dick Blick Art Materials) is used in place of red-pigment concentrate and venous cannulation and perfusion is performed.
Circuit Two circuits and reservoirs are prepared as previously described by Russin et al.21 Briefly, one end of a 30-cm
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length of 1/400 ID tubing is inserted into a 19-L reservoir (Fig. 2). The other end is attached to a 1/400 ! 3/800 Luer connector with a 3-way stopcock attached. One end of a 30-cm length of 3/800 ! 3/3200 ID tubing is attached to the 1/400 ! 3/800 Luer connector and the other to the inlet of a constrained vortex centrifugal pump (Biomedicus BP80 Bio-Pump; Medtronic, Minneapolis, MN). A 30-cm length of 3/800 ! 3/3200 vinyl tubing is attached to the outlet of the BP80. Within this segment of tubing is a 3/800 ! 3/800 Bio-Probe (Medtronic) for measurement of flow. A 15-cm length of 3/800 ! 3/3200 vinyl tubing is connected to the distal end of the Bio-Probe. The opposite end of this tubing is connected to a 3/800 ! 1/200 brass coupler. The 1/200 end of the coupler is attached to 120 cm of 1/200 vinyl waterproof electrical conduit ending with a 1/200 ! 3/800 ! 1/ 200 T-connector. A 1-m length of 3/800 ! 3/3200 vinyl tubing is attached to the 3/800 outlet of the T-connector ending with a 3/800 ! 1/400 reducing Luer connector. High-pressure tubing is attached at this Luer connector and is then attached to pressure monitoring. The 5-cm segment of 1/400 ! 3/3200 ID tubing from the Sims connector cannula is attached to the 1/400 end of the reducing Luer connector. The distal 1/200 end of the 1/200 ! 3/800 ! 1/200 Tconnector is attached to 1 m of 1/200 ID waterproof electrical conduit that is attached to 1/200 ! 1/200 levered ball valves. One meter of 1/200 ID waterproof electrical conduit is attached to each of the ball valves ending in 1/200 ! 3/800 ! 1/200 T-connectors. The arterial and venous circuits are then duplicated attaching the second cadaver to the system. The distal 1/200 end of the final T-connector is dead-ended pending attachment of mirrored systems.
Priming The output of the BP80 centrifugal pump is severely limited by the presence of air and is afterload and preload sensitive. The pump is primed with a 60-mL syringe
181 attached to the 3-way stopcock between the BP80 and the 19L reservoir by drawing fluid from the reservoir, clamping and infusing fluid toward the pump. This is repeated until the proximal tubing and BP80 are deaired (approximately 100 mL). A tubing clamp is then placed on the outflow tubing of the pump. Flow is dependent on rotations per minute (RPM) set on the Medtronic Bio-Console; this is initially set to 1,000 RPM. The outflow clamp is then removed and placed on the venous circuit, whereas the arterial circuit is systematically primed by opening clamps and Luer connectors. After this, the clamp is moved to the arterial tubing proximal to the brass coupler and the venous system is primed in a similar fashion.
Pressurization Once the circuit is deaired, the cadaver vasculature is pressurized. Pump speed, in RPM, is titrated depending on the number of cadavers being pressurized (1 or 2 as of this writing). Typically 2000 RPM is sufficient to achieve a mean arterial circuit pressure of 80 mm Hg in 2 cadavers. Venous pressure is regulated to 15 mm Hg through RPM titration. The cadaver vasculature remains pressurized with inflow circuits fully clamped for minutes before capillary leak and vessel accommodation depressurizes the vasculature and abdominal distention begins, thus the need for a large available fluid reservoir.
Pulsatility When pulsatile blood flow is advantageous for anatomic findings, such as in ultrasonography-guided internal jugular central line placement, the arterial circuit is modified. An extracorporeal balloon within a constrained reservoir adapted with a 3/800 coupler is placed in the arterial circuit. The balloon is attached to the 3/400 inlet of the reservoir covered with surgical mesh to prevent prolapse of the balloon into the nonfluid path. The balloon is then inflated at a rate to mimic normal heart rate. The reservoir is primed with the arterial circuit attached to a 3/800 coupler inserted in the reservoir. Fluid exits the reservoir via a 1/200 connector that is staged down to 1/400 to enable connection to the Sims connector previously placed in the femoral artery. The balloon inflates manually although an intermittent pump or balloon inflation can be achieved mechanically. On inflation, fluid is displaced forward causing a positive pressure, and on deflation, fluid is displaced retrograde until the next cycle. Pulse pressures are recorded via right radial artery catheterization with this method (Fig. 3).
Indocyanine green angiography
Figure 2 The arterial and venous circuits connect the arterial and venous femoral cannulas with the centrifugal pumps.
We evaluated full body, regional, hand, visceral organ, and isolated flap perfusion using the SPY system (Novadaq, Bonita Springs, FL). Ten milliliters of water is used to
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Figure 3
Distal cannulation of the radial artery (A) and pressure tracing (B) showing nonpulsatile pressure 89/82 mm Hg.
reconstitute a 25-mg vial of indocyanine green (ICG). The 2.5-mg/mL ICG vial (10 mL) is added to 500 mL of NS. The 500-mL bag of ICG 1 NS is emptied into a 6-L reservoir, and 180 mL of cadaveric blood, 250 mL of concentrated red nontoxic paint (premium tempera; Dick Blick Art Materials), and 50 mL of NS are added to the reservoir. The reservoir is then filled to 5.5 L with tap water. The inlet of the centrifugal pump is placed within the reservoir and set to deliver 1 L/min to the cannulated femoral vein and artery. After infusion, the delivery tubing is clamped and the area is imaged.
centrifugal pump. Arterial pressure was controllable and could be established from 0 to 200 mm Hg (Fig. 4). Brisk bleeding from large vessels on arteriotomy was encountered at blood pressures higher than 40 mm Hg. Successful capillary bleeding at the skin level was verified by skin incision and was repeatable at pressures higher than 90 mm Hg. In addition, skin color changes are noted at
Cost analysis The total cost of supplies for a single cadaver including durable and disposable goods as well as personnel time was recorded and summed.
User experience With approval from the institutional review board, medical students, residents, fellows, and attending physicians were surveyed after use of the perfused cadaver model. Survey participants were asked to rate their level of agreement with statements regarding the perfused cadaver model’s effectiveness in teaching, learning technique, authenticity, and safety in performing the procedure (1 5 strongly disagree, 2 5 disagree, 3 5 neither agree nor disagree, 4 5 agree, 5 5 strongly agree). The Student t test was used to compare pretest and post-test confidence level based on a 5-point scale (1 5 least confidence, 5 5 highest confidence) with an alpha level of .05.
Results Establishment of arterial pressure On infusion into the femoral artery, pressures were measured as a function of the rate of infusion via the
Figure 4 Laparotomy showing pressurized abdominal aorta and inferior vena cava.
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this pressure, secondary to passage of perfusate through the skin (Fig. 5). Pressures higher than 120 mm Hg are achievable but did not add value to simulation and resulted in rapid diffuse edema of the cadaver.
Establishment of venous pressure Venous pressure was controllable by infusion of perfusate to achieve pressures from 1 to 20 mm Hg. A pressure of 20 mm Hg has been sufficient to enable internal jugular, subclavian, and femoral central venous catheter placement (Fig. 6). Evaluation of central venous pressures through cannulation demonstrated maintenance of pressures while infusion takes place. Jugular venous distension was present on physical examination. Valvular competence was noted in peripheral veins, preventing venous flow to the extremities. Evaluation of central venous flow with ultrasonography (SonoSite, Bothell, WA; Fig. 7) demonstrated adequate filling of central veins and is used to verify clot removal and patency of flow in the internal jugular vein before cadaveric perfusion. Previous studies have demonstrated the possibility of direct arteriovenous circulation by creation of arteriovenous shunts,20 but we found difficulty in maintaining arterial pressure and perfusate volumes, and thus, we chose to solely create venous pressure through direct cannulation.
Skin Skin perfusion was noted by color change on pressurization, secondary to perfusion with colored dye. There was a diffuse change in color throughout the entire cadaver or region perfused. In addition, on perfusion of the cadaver, there was notable perfusion with ICG evaluation of the skin. Importantly, after incision with a scalpel, brisk bleeding from the subdermal plexus was noted, which responded appropriately to electrocautery.
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Heart Cardiac perfusion was noted by direct evaluation through sternotomy and thoracotomy. We noted distention of the atria and ventricles and noted on ICG Perfusion scanning that there was clear perfusion of coronary arteries and veins. Laceration of the heart at physiologic pressurization demonstrated brisk bleeding from the chamber as well as the coronary circulation (Fig. 8).
Lungs Pulmonary parenchymal perfusion was noted grossly by color change on perfusion and gross bleeding on incision of tissue. In addition, perfusion of the pulmonary capillaries was easily visualized and documented with ICG perfusion scanning. Pulmonary injury results in similar bleeding and air leak is seen clinically, as has been demonstrated in previous publications (Fig. 9).
Brain Brain perfusion noted similarly to other organs by filling of cerebral vessels and bleeding when vessels were lacerated. True perfusion of neuronal tissue was difficult to appreciate by color change, but rapid, diffuse cerebral edema was noted with perfusion pressures greater than 80 mm Hg suggesting parenchymal perfusion.
Bowel Fluid translocation of intravascular fluid into the bowel lumen resulted in gastric and bowel distention after the initiation of the conditioning fluid and continued through the pressurizing cycles. Early placement of an oral-gastric tube helps to counteract the abdominal distention seen during perfusion sessions (Fig. 10).
Figure 5 Perfused cadaveric models demonstrate skin color changes and dermal bleeding. (A) Planned elliptical incision. (B) Bleeding incision. (C) Electrocautery required for hemostasis.
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Figure 6 Pressurized subclavian artery and vein after clavicle disarticulation.
Figure 8 Exposure of heart with laceration of the right ventricle demonstrating bleeding.
Cost analysis
Medicine, and by medical students. This model results in tissues that bleed when cut, pulsatile vasculature for exposure, physiologic pressurized vessels for venous and arterial access and interventional therapeutics, the ability to assess shunt patency and suture line resiliency (Fig. 11), and creation of high-risk injuries for surgical team crisis training. The details of these models are beyond the scope of this article.
The total cost of a single perfused cadaver model was calculated to $1,262.55. The pump and pump console cost $1,050.00, and the cost of reusable materials including tubing, reservoir, adapters, sensors, clamps, and valves was $212.55. Once the initial investment is made, subsequent models cost $37.10 in disposable goods and $50.00 per hour in personnel time. This does not account for facility fees and cost of procuring cadavers, which varies according to institution.
Applications of model The pressurized cadaver has been accessed and used 122 times by 969 trainees for surgical simulation by the Departments of Acute Care Surgery, Cardiothoracic Surgery, Neurosurgery, Plastics and Reconstructive Surgery, Vascular Surgery, Emergency Medicine, Internal Medicine, Dermatology, Pediatrics, Pulmonary and Critical Care
Figure 7 vessels.
Ultrasonography-assisted
evaluation
of
jugular
User experience evaluation The perfused cadaver model has been applied to multiple areas of surgical and medical education. A total of 969 trainees were surveyed, including 47 attending faculty, 54 fellows, 854 residents, and 14 medical students. The model received high reviews for authenticity and utility for increasing knowledge, teaching new techniques, and improving procedural safety. Confidence in preprocedure skills across all participants was 2.85, and postprocedure
Figure 9 Right upper (RUL) and middle lobe (RML) with right ventricle (RV) and right coronary artery (RCA) angiogram with ICG. Note the filling of RCA and filling of the accompanying small coronary vein (SCV). Anterograde vs retrograde vein filling cannot be determined.
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Figure 10 Laparotomy after extended pressurization time demonstrating significant bowel wall edema and distension.
confidence was 4.20 (P , .00; Table 1). Our laboratories have used this model as a surrogate for improvement in skills as currently we have not employed a direct objective measurement of skills assessment.22,23
Comments The successful establishment of cadaveric circulation was described by Garrett18 in 2001 in an attempt to create a model for the evaluation of vascular devices and for the simulation of vascular surgical procedures. The abstract on the patented method describes its purpose, ‘‘for study of vascular function, research and teaching of surgical procedures and general medical education.’’ Garrett’s18 model is the first reported attempt to create a surgical simulation model using vascular reconstitution in fresh human cadavers. The primary goal of their method involved the establishment of arterial flow by inflow through a proximal artery and outflow through a distal artery. This method was successful in creating antegrade arterial flow and
Figure 11 Brachial artery shunt placement with visible flow across shunt.
185 demonstrated utility for simulation of open and endovascular procedures. Limitations of this initial model were that the venous system was not perfused and subsequently, could not be involved in surgical simulations, and the perfusate did not simulate blood authentically. Despite these minor limitations, the initial article describes the successful performance of multiple procedures on more than 200 cadavers. Aboud et al19 described a method of establishing arterial pressure and flow in a similar manner through isolated perfusion of a cadaver head. Arterial inflow was established through the carotid artery and outflow through the contralateral arterial system, which allowed for true arterial flow. Although a true arteriovenous circulation was not established, the importance of venous pressure was recognized and solved by retrograde venous perfusion, allowing for physiologic venous pressure. This method allowed for simulation of neurosurgical procedures and simulation of difficult pathology such as ruptured aneurysms. In this model, arterial and venous perfusates were made through the addition of dye to tap water, which demonstrated accurate filling of cerebral arteries and veins. This team later adapted this model to a full cadaver described in 2011 by cannulation of large central vessels in the cadaver and attachment to an extracorporeal pump.20 Filling of the venous system was static through a large catheter in femoral vein. True arteriovenous circulation was also created by formation of arteriovenous shunts through connections between large vessels or through distal extremity arteriovenous connections. This method then allowed their group to establish the utility of this model to simulate multiple surgical procedures, primarily focused on trauma surgery. In the quest to create the ideal surgical simulation, these previous models made great strides. At our institution, we have added to their ideas by addressing some of the limitations of the model. One primary issue in the utility of these models is the manner in which the perfusate solution is delivered to the vasculature and the duration of pressure which can be maintained. The previous works are unclear on exactly how the cadaveric vascular pressure was maintained and measured. Our pump was attached to a large volume reservoir (19 L and replenishable throughout the procedure) and pressure was measured as a function of the speed of the pump. The nature of centrifugal pumps makes them the ideal driver for this application. Providing a fluid volume that can easily be replenished solves the preload requirement, and its nonpositive displacement properties make it a safe alternative to roller pumps. Earlier work included the use of 1-L pressure bags or blood transfusion bags to enable arterial system filling, which cannot accommodate prolonged pressurization. Prolonged and carefully controlled pressure is required for maintenance of physiologic pressures during procedure simulation, especially when the procedure is advanced or lengthy. In addition, fluid accumulation in the peritoneal cavity from leakage of the small vessels of solid organs and peripheral tissues results in massive edema. This effect can limit the
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Table 1
Mean results of perfused cadaver survey results
I Gained new knowledge
I learned new techniques
The pressurized cadaver aids in realistic anatomic dissections
4.85
4.86
4.74
The pressurized cadaver adds reality to surgical procedures
I feel I will be safer performing this procedure in a clinical setting
Preprocedure confidence
Postprocedure confidence
4.77
4.76
2.85
4.20*
*Preprocedure compared to postprocedure confidence P , .00.
fidelity of the surgical simulation. Another means of managing this side effect is regulating the time of actual forward flow to the cadavers. For simulation-based training a minimum, continuous forward flow is established, with increased flow during procedural tasks, such as line placements and surgical exposures. For technical evaluation sessions, such as shunt patency, suture line resilience, and pedicle perfusion, a single clamp at the pump outlet halts forward blood flow until the surgeon directs the initiation. In this manner, we can control the pressure and the flow, as it pertains to the procedure itself, to help minimize the interstitial loss of fluid. Building on the previous work in establishing postmortem vascular perfusion and pressure, we hope to broaden the application of the model. In addition to the use of the model in vascular, trauma, and neurosurgical procedures, this model can be extended to other areas of surgical and procedure-based medical education. Both Aboud’s19 and Garrett’s18 previous described methods can be applied toward large vessel procedures, but the application toward cutaneous procedures is first described in our model. This extends the utility of the model to more novice users to complete procedures such as basic dissection in tissue planes, as well as excision of cutaneous lesions. The demonstration of adequate perfusion at the small vessel level with ICG angiography has helped us ensure the integrity of the model at the angiosome level. As was established in the descriptions by Aboud19 and Garret18, the presence of endovascular debris in the form of clot is problematic in the establishment of these models. This problem primarily affects the arterial tree but can similarly manifest in the venous system. Initially, techniques used for light embalming were used to treat the arterial and venous systems before fluid infusion. Although this produced good results and enabled mean systemic arterial pressures of more than 100 mm Hg and equally physiologic femoral venous pressure, we found migration of venous clot prohibitive to particular procedures. To counter this, we began a routine of serial tap water pressurization and depressurization maneuvers combined with light chest compression, abdominal thrusts, and neck massage. This technique has replaced the use of previous conditioning fluids and has allowed for reliable cadaver pressurization in both arterial and venous trees. Both Garrett18 and Aboud19 describe the difficulty and dissimilarity of the use of water or crystalloid solutions for
blood simulation. Toward the end of using a blood simulation that was more physiologic and more similar to blood, we created a solution using pigmented dye, tap water, saline, and cadaveric blood. This results in a perfusate with consistency that more closely resembles human blood, responds better to electrosurgical coagulation, and decreases rapid edema formation secondary to higher osmotic pressure. The limitations of this procedure stem from the obvious difficulty in availability of fresh cadaveric tissue. Expense of the available specimens is clearly a limiting factor in widespread use. Safety considerations of the use of human tissue are an ever present problem. The anatomic and technical expertise in creating this model and the specialty specific machinery are significant limitations, and our technician has evolved his practice over time. At our institution, all costs have been covered by grants aimed at improving the educational experience of the resident house staff, in addition to a dedication toward improving patient safety. The equipment was similarly donated by our surgical specialty departments; thus, it is very difficult to estimate the exact cost of preparing the model. Regional differences in the procurement costs of fresh tissue as well as the equipment involved may vary but likely will be prohibitive in establishment of multiple centers with this type of surgical simulation. Establishment of high-fidelity surgical simulation models has become a priority in surgical education. The highest fidelity anatomic model for surgical simulation is the human cadaver, but the cadaver lacks physiologic parameters that would make simulation authentic. Like the models designed by Aboud and Garrett, the ultimate utility is for this model is the ability to simulate live tissue operations. Our series of perfused cadavers currently represents an addition to the broad application of the method to surgical education that has been started by previous studies. The opportunity for residents to perform operations in a high-fidelity environment before entering the operating room has the benefit of providing experience without the threat of danger to the patients as a result of surgeon inexperience.
Conclusion The use of pressurization techniques in the cadaver increases educational value of the fresh human cadaver as education resource.
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