Spray coagulation with snare-tip versus argon plasma coagulation: An ex vivo study evaluating tissue effects

Background and study aims Argon plasma coagulation (APC) is an effective and safe modality for many gastrointestinal conditions requiring hemostasis and/or ablation. However, it can be quite costly. A potentially more cost-effective alternative is snare-tip spray coagulation (SC). This study aimed to determine whether SC would be a safe and effective alternative to APC using an ex-vivo model. Methods Using two resected porcine stomach, 36 randomized gastric areas were ablated for 2 seconds with either APC at 1.0L/min 20W (APC20) and 1.4L/min 40 W (APC40) or SC with Effect 2 60W (SC60) and 80W (SC80) from 3mm. Extent of tissue injury was then analyzed histopathologically. Results The mean coagulation depth was 790159 mu m and 825 +/- 467 mu m for SC60 (n = 9) and SC80 (n = 8), respectively. This was compared to 539 +/- 151 mu m for APC20 (n = 8) and 779 +/- 267 mu m for APC40 (n = 9). Mean difference (MD) in coagulation depth between SC60 and APC40 was 12 mu m (95% confidence interval [CI], -191 to 214 mu m; P = 0.91) and was 47 mu m (95%CI, -162 to 255 mu m; P = 0.81) between SC80 and APC40. There was a greater depth of injury with APC40 (MD, 240 mu m; 95%CI, 62 to 418 mu m; P = 0.04) and with SC60 (MD, 252 mu m; 95%CI, 141 to 362 mu m; P = 0.004) when compared to APC20. Mean cross-sectional area of coagulation was 2.39 +/- 0.852 mm(2) for SC60 and 2.54 +/- 1.83mm(2) for SC80 compared to 1.22 +/- 0.569 mm(2) for APC20 and 1.99 +/- 0.769mm(2) for APC40.Seventy-eight percent reached the muscularis mucosa (MM) and 11% the submucosa in the SC60 group compared to 50% and 38% in SC80 and 56% and 11% in APC40, respectively. Thirty-eight percent of APC20 specimens reached the MM. The muscularis propria was unaffected. Conclusions This small ex-vivo study suggests that SC60 and SC80 may be safe alternatives to APC40 with comparable coagulation depths and area effects.