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Evaluation of made-for-purpose ring cutter devices for the removal of modern hard ring materials
Jeffrey J Perry1, Sara Khaksari2, Gabriel Sandino-Gold2
1Department of Emergency Medicine and School of Epidemiology, Public Health and Preventative Medicine, University of Ottawa, Acute Care Research Program Ottawa Hospital Research Institute, Ottawa, ON, Canada. jperry@ohri.ca.
Objectives:
Ring entrapment is a common problem in emergency departments. With modern durable metals such as tungsten carbide, titanium, and stainless steel, traditional tools may be ineffective. We evaluated the performance of four purpose-designed ring cutter devices on three hardened ring materials.
Methods:
Medical providers tested four ring cutting devices-the M5118 Stainless Steel Manual Ring Cutter (Acme United Corporation), Dolphin Ring Cutter (Ring Rescue Inc.), GEM-II Ring Cutter (A-Z Tec Medical Ltd.), and Raptor Shears (Leatherman Tools)-on tungsten carbide, titanium, and stainless steel rings (2.5 mm × 6 mm, size 9-10). Outcomes included successful ring removal, time to removal, ease of use, and user confidence. Research assistants timed each cut. Participants rated ease of use and confidence after each cut.
Results:
Twenty-one participants (mean age 40 ± 10 years; 76% female) included seven physicians, nine registered nurses, two registered practical nurses, and three patient care attendants. Participants combined performed 242 unique ring cut attempts. The Stainless Steel Manually-Operated Ring Cutter failed on all rings. The Raptor Shears succeeded on titanium 25% of the time but failed on others. The GEM-II Ring Cutter succeeded in 62% of tungsten carbide, 65% of titanium, and 83% of stainless steel rings. The Dolphin Ring Cutter successfully removed all rings. Mean (SD) cut times in seconds were 251 (92) for Dolphin, 561 (239) for GEM-II, and 292 (160) for Raptor. Dolphin scored highest for ease of use 4.8 (0.5) and confidence 4.8 (0.4).
Conclusion:
For cutting modern hard ring metals, the Dolphin Ring Cutter was the optimal tool of the four assessed, being able to cut through all three materials. The manual ring cutter and trauma shears could not cut through these hardened metals. The Dolphin Ring Cutter was found to be easy to use, and participants had a high degree of confidence in this tool.
