Cold snare for your polyps <10mm; cold snare for the planet

“Simplicity is the ultimate sophistication” – Leonardo da Vinci

In the world of modern medicine, where technological advancements often steal the spotlight, the beauty of simplicity sometimes goes unnoticed. Endoscopists and researchers tend to be fascinated by impossible endoscopic resections, navigating the peritoneum, testing new endoscopic devices, or study designs founded in advanced statistical methods that are hard to understand for most Earthlings. Yet, it is precisely in simplicity that we often find the most elegant solutions to complex challenges. The study by Rex et al., focusing on universal cold snaring of colorectal polyps ≤10mm, is a shining example of how a straightforward approach can deliver remarkable results [1]. This study not only simplifies procedures, but also offers a practical solution to the growing environmental concerns surrounding the environmental impact of gastrointestinal endoscopy [2].

Small colorectal polyps are the most common polyps found in clinical practice. Cold forceps polypectomy performs similarly to cold snare polypectomy for polyps <4mm in terms of complete resection and safety [3]. Yet, it is time we look beyond purely histologic outcomes and grasp the full picture of the problem. In this issue of Endoscopy, Rex et al. prospectively assessed the feasibility of cold snaring all colorectal lesions ≤10mm in size in 677 consecutive colonoscopies performed by an experienced endoscopist. The success rate of resection was >99% regardless of polyp size (≤3mm vs. 4–10mm). This means that about 35 and 47 cold forceps were spared per 100 screening and surveillance patients, respectively. Interestingly, pedunculated polyps were not excluded, in line with recent data suggesting that cold snaring is feasible and safe [4], although a subgroup analysis was not provided. Sparing the use of a biopsy forceps translated into a decrease in cost of approximately $4 US per procedure.

“The relevance of this study likely does not lie in cost savings or the assessment of resection margins in small polyps; it is about placing efficiency and sustainability in the spotlight.”

The relevance of this study likely does not lie in cost savings or the assessment of resection margins in small polyps; it is about placing efficiency and sustainability in the spotlight. Cold snaring appears to be a more pragmatic choice for small polyps as it allows the resection of larger polyps with a single device and is usually cheaper than a biopsy forceps [5]. The reduction in plastic waste reported is substantial, with an estimated saving of 11g per screening procedure and 14.7g per surveillance procedure. The numbers may not seem impressive on a per-procedure basis, but the environmental impact of such a shift in practice is not to be underestimated, considering that over 22 million gastrointestinal endoscopies are performed annually in the USA [6].

The study could benefit from a more in-depth analysis of the environmental benefit of the universal cold snaring strategy. The carbon footprint savings were not evaluated in this study but should also be considered. A recent study suggested that the carbon footprints of a snare and a biopsy forceps are similar, approximately 0.41kg CO₂ equivalents per device [7]. But it is not only about sparing a biopsy forceps, it is also about which biopsy forceps we spare. In this regard, the carbon footprint of biopsy forceps can differ by up to a third, depending on the manufacturer [7]. A preferably green purchasing policy in the endoscopy department leads to a substantial reduction in CO₂ emissions [8]. Furthermore, the authors also missed out an evaluation of the total waste reduction weight, omitting that stainless steel represent nearly 50% of the composition of forceps, and the median forceps weight is five times the plastic weight (median 57g, range 46–66g) [7]. Additionally, there is no mention of whether packaging or devices were disposed of correctly or recycled, a crucial aspect in minimizing the environmental impact and an area often neglected in most units.

Finally, one may question the clinical relevance of sending most small polyps for histopathologic analysis in the hands of an expert colonoscopist, considering that one biopsy sample can release as much as 300g of CO₂ equivalents [2]. A “resect and discard” strategy seems more appealing with the use of a snare than with a cold forceps, as it eliminates the need to exchange the accessory through the working channel and allows for a broader resection margin.

The study acknowledges its limitations, mentioning that it is possible that not all endoscopists will find universal cold snaring equally attractive from a technical perspective. This limitation may not seem a major impediment for many endoscopists but should not be overlooked. A recent randomized controlled trial indicated that the learning curve for cold snare polypectomy is long and current training methods may be insufficient to ensure trainees achieve competency by the completion of their fellowship program [9]. Also, the authors highlight that cold snaring might not be feasible or adequate in the presence of scar tissue or when submucosal invasion is suspected. Importantly, only eight polyps were resected by hot snare polypectomy. The use of hot snare polypectomy does not seem justified for most small polyps as it increases the risk of delayed bleeding [10] and probably the environmental burden, considering that cold snaring avoids the need for a disposable electrode, submucosal injection, and an electrosurgical unit.

In conclusion, the study by Rex et al. indicates that cold forceps should live up to their name (“biopsy forceps”) and be reserved for biopsy sampling, and probably abandoned for the resection of diminutive colorectal polyps. By adopting the straightforward practice of universal cold snaring for polyps ≤10mm, healthcare facilities can simplify their procedures, reduce cost and waste, and make a meaningful contribution to environmental sustainability. Future polypectomy guidelines should consider this domain when formulating recommendations. The study serves as encouragement for endoscopists to explore simpler and greener approaches in their daily operations. Every device spared counts. Every small step counts.

Publication History

Article published online:
06 December 2023

• References

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