TissueDB/Materials/Gelatin
License: CC-BY-SA-3.0 by Danielle dk
Gelatin is a protein derived from collagen, used in surgical simulation to create tissue phantoms with tunable mechanical properties. Ballistic gelatin formulations provide realistic tissue drag during needle insertion and cutting, while softer preparations simulate organ parenchyma for ultrasound phantoms. Animal-derived but widely available and cost-effective for high-volume training programs. It is bought as dry powder or as gelatin sheet stock, and the blend of gelatin and water that is poured into a mould and left to set is a gelatin mix.
Gelatine's limits as a phantom matrix have been measured against agar. Gelatine "requires refrigeration, both to set the model when poured and to minimise spoilage"; in side-by-side testing the gelatine models "were much more fragile and compressible than tissue and were prone to rapid degeneration from needle sticks and heat exposure", and a 10% gelatine model was more durable and denser than a 5% one. Agar models of similar density withstood more punctures for venepuncture practice. Gelatine is nonetheless the cheaper matrix: enough for one 5% model cost about US$2.50 bought through Amazon.com and about US$1.50 through online suppliers in Cape Town, against about US$5.00 and US$3.60 for agar.[1]
Tissues
| Tissue | Visual | Tactile | Simulator | Notes |
|---|---|---|---|---|
| Soft Tissue | Pediatric Forearm Fracture Simulator | Mix 80 g unflavoured gelatin in 400 mL room-temperature water, add 400 mL heated water; refrigerate ~4 hours to set. Transparent when left uncoloured; add food colouring for an opaque set. | ||
| Muscle | Z-Plasty Simulator | Gelatin:glycerine:water ratio 8:8:2 with red food colouring and wool substrate. Microwave 30 seconds, baste until jam consistency. | ||
| Subcutaneous fat | Z-Plasty Simulator | Gelatin:glycerine:water ratio 2:6:12 with yellow food colouring and wool substrate. Set time 1 hour. Layer multiple pieces for thickness, glue with connective tissue paste. | ||
| Connective Tissue | Z-Plasty Simulator | Gelatin:glycerine:water ratio 5:2:10, no colouring, no substrate. Adhesive paste between tissue layers. | ||
| Skin | Z-Plasty Simulator | Gelatin:glycerine:water ratio 10:4:20 with food colouring for skin tone and 15-denier stocking substrate. Set time 1 hour. | ||
| Esophagus | Neonatal ETT Ultrasound Simulator (Qaim Ali) | Blended with psyllium fibre and cored with a hollow lumen to form a neck-ultrasound phantom.[2] | ||
| Kidney | Ewald Percutaneous Renal Access Trainer | 10% ballistic gelatin + 30% iohexol (Omnipaque 300) + 60% water by weight; the added contrast makes the set gelatin radio-opaque for fluoroscopic needle targeting.[3] | ||
| Common Femoral Artery (femoral access mold) | Pulsatile REBOA Simulator (Keller) | Ultrasound-compatible gelatin mold capable of transducing discernible pulsations. Used for full percutaneous femoral access practice (needle puncture, Seldinger conversion, sheath upsize, balloon deployment); reusable up to four deployments before replacement. Source verbatim: "An ultrasound compatible gelatin mold capable of transducing discernible pulsations enables REBOA deployment starting with percutaneous vascular access and ending with balloon inflation".[4] | ||
| Blood Vessel (PDA and aorta) | Patent Ductus Arteriosus Ligation Simulator | 15 g gelatin combined with 40 g glycerol and 0.5 g powdered red pigment, made up to 100 mL with cold water; left to stand 20 minutes, then stirred over low heat for about 10 minutes without boiling. Cast as gelatin-glycerol gel in a mould with plastic inserts that form the PDA and aorta lumen for dissection and double-ligation practice.[5] | ||
| Pleura (parietal) | Patent Ductus Arteriosus Ligation Simulator | Cast from the same gelatin-glycerol mixture as the vessel; the trainee dissects the parietal pleura off the aorta to expose the PDA.[5] | ||
| Subcutaneous tissue | UGHE Low-Cost Soft-Tissue Simulation Module | An approximately 2 cm layer of pigmented gelatin stands in for the subcutaneous tissues, cast between a sponge base and a felt-and-tape skin. In the nodule model the same layers are used, with a kidney bean instead of the lotion as the lesion the trainee excises. The source gives no gelatin concentration - only the layer thickness, the pigmentation and the cost: US$0.40 per abscess model and US$0.34 per nodule model in Rwanda. It sets overnight, and the authors record refrigeration as a real constraint on deploying the models where power is unreliable.[6] |
References
- ↑ Earle M, Portu GD, DeVos E. Agar ultrasound phantoms for low-cost training without refrigeration. Afr J Emerg Med 2016;6(1):18-23. DOI: 10.1016/j.afjem.2015.09.003. PMID: 30456059. PMC: PMC6233231.
- ↑ Merali HS, Tessaro MO, Ali KQ, Morris SK, Soofi SB, Ariff S (2019). "A novel training simulator for portable ultrasound identification of incorrect newborn endotracheal tube placement – observational diagnostic accuracy study protocol." BMC Pediatrics 19:434. DOI: 10.1186/s12887-019-1717-y. PMID: 31722685. PMC: PMC6852924.
- ↑ Ewald JM, Cheng JW, Engelhart SM, Wilkinson MC, Hajiha M, Wagner H, Baldwin DD. A realistic, durable, and low-cost training model for percutaneous renal access using ballistic gelatin. Turk J Urol 2019;45(1):31–6. DOI: 10.5152/tud.2018.43569. PMID: 30668307.
- ↑ Keller BA, Salcedo ES, Williams TK, Neff LP, Carden AJ, Li Y, Gotlib O, Tran NK, Galante JM. Design of a cost-effective, hemodynamically adjustable model for resuscitative endovascular balloon occlusion of the aorta (REBOA) simulation. J Trauma Acute Care Surg. 2016 Sep;81(3):606–611. DOI: 10.1097/TA.0000000000001153. PMID: 27270855.
- ↑ 5.0 5.1 Cardiac Surgical Skills Training Module, SELF-Training team / Global Surgical Training Challenge, Appropedia, 2021. Build and operation: Phase 2 (Simulator Setup).
- ↑ Wittenberg RE, Bryce-Alberti M, Shimelash NZ, Masimbi O, Kratky LE, Thompson AA, et al. Low-cost simulation models for soft-tissue procedures for medical student education in Rwanda. BMC Medical Education 2025;25(1):1271. DOI: 10.1186/s12909-025-07910-4. PMID 41034833. PMC PMC12487576. Licensed CC BY-NC-ND 4.0.