TissueDB/Simulators/Resuscitative Endovascular Balloon Occlusion of the Aorta Simulator (Keller)

The Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) Simulator (Keller) is a high-cost REBOA trainer. Keller 2016 built it around a commercial pulsatile blood pump rather than from locally available materials. It is for practising percutaneous femoral access, Seldinger conversion, and 12 French sheath upsizing. It is also for practising CODA balloon deployment and Zone 1 and Zone 3 occlusion identification.^[1] The pump drives a latex and polyvinyl chloride (PVC) vascular circuit that reproduces pulsatile flow. Cardiac output is 1.7 to 6.8 L/min. Systolic pressure is 54 to 226 mmHg. A Laerdal adult torso houses the circuit and two interchangeable groin access molds. One mold is ultrasound-compatible gelatin, for percutaneous and cut-down access. The other is foam, with a 12 Fr sheath pre-placed, for deployment-only practice. The torso gives external Zone 1 (xyphoid) and Zone 3 (umbilicus) landmarks for identification.

Source — Keller et al. 2016 (PMID 27270855) supplies every material, build step, dimension and cost on this page, unless a cell notes otherwise.^[1]

The source describes the finished design rather than a step-by-step build, so the phase order below is a reconstruction. The source does not give segment lengths, the gelatin or foam mold fabrication method, or the order of priming versus transducer installation (the three-way stopcocks must be in place before priming, since the circuit is primed through them).

1. Cut a length of 2.5 cm inner diameter (ID) latex tubing for the abdominal aorta segment.
2. Cut four lengths of 1.3 cm ID latex tubing for the right and left common iliac and right and left common femoral artery segments. Source verbatim: "The abdominal aorta was made out of a 2.5-cm inner diameter (ID) latex tubing, and the iliac and femoral arteries were made out of 1.3-cm ID latex tubing."

1. Join the segments with polymer connectors at the branches/bifurcations and size transitions.

1. Branch additional latex tubing off the left common femoral artery and route it back to the perfusion pump.
2. Install a one-way check valve in the return tubing to prevent retrograde flow.

1. Install a proximal circuit shunt to shunt antegrade flow during balloon occlusion.

1. Connect the pump inflow and outflow using 1.3 cm ID polyvinyl chloride (PVC) tubing.

1. Construct the ultrasound-compatible gelatin femoral access mold (supports percutaneous and cut-down access). The source does not specify the mold-fabrication method.
2. Construct the foam femoral access mold with the 12 Fr Cook Medical sheath pre-placed.

1. Place the entire vascular circuit and access molds inside the Laerdal Medical adult simulated torso, oriented so the xyphoid (Zone 1 landmark) and umbilicus (Zone 3 landmark) are externally palpable.

1. Prime the circuit with water and purge air through the integrated three-way stopcocks.

1. Install one Edwards Lifesciences arterial pressure transducer in the proximal aorta and one in the left common femoral artery; connect each to a Welch Allyn invasive blood pressure monitor.

1. Connect the Harvard Apparatus Model #1423 pulsatile pump; set the stroke volume and rate to the desired clinical scenario (for example, hypotensive trauma).

1. Confirm cardiac output 1.7 to 6.8 L/min, systolic blood pressure 54 to 226 mmHg, diastolic blood pressure 14 to 121 mmHg, and heart rate 30 to 80 bpm.

1. Perform a test REBOA deployment via the right common femoral artery (gelatin or foam mold per scenario): percutaneous puncture with a Teleflex-Arrow arterial catheter; confirm placement by pulsatile flow and ultrasound; Seldinger conversion with a 0.035-inch Boston Scientific Amplatz wire; upsize to a 12 Fr Cook Medical sheath; advance a 12 Fr 32-mm Cook Medical CODA balloon catheter to the target zone; inflate the balloon.
2. Confirm anatomic placement by lifting the simulated torso and palpating the inflated balloon within the aorta.
3. Confirm the therapeutic response: proximal systolic blood pressure rises 10 to 62 mmHg, the distal arterial waveform dampens, and distal systolic blood pressure drops to 0 mmHg.

For training scenarios (Zone 1 versus Zone 3 deployment, hypotensive-trauma simulation, two-mold workflow comparison), see the corresponding SELF Module for REBOA training scenarios.

This simulator is bench-validated for hemodynamic performance. The pump and circuit generate a simulated cardiac output of 1.7 to 6.8 L/min, systolic blood pressure of 54 to 226 mmHg, diastolic blood pressure of 14 to 121 mmHg, and a heart rate of 30 to 80 bpm. On balloon inflation, proximal systolic pressure rises by 10 to 62 mmHg, the distal arterial waveform dampens, and distal systolic pressure drops to 0 mmHg. The simulator was shown in use at a University of California Davis Medical Center trauma and vascular surgery workshop before clinical adoption.

The simulator has not been validated for skill acquisition or retention. The authors wrote: "the pulsatile simulator has not been validated in terms of skill acquisition and retention; however, validation studies are being planned."^[1]

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