Clinical practice update: Electrosurgery guidance refines endoscopy practice

A new AGA clinical practice update highlights that safe and effective electrosurgery in gastrointestinal endoscopy is determined not only by device settings, but also by operator technique and tissue factors, with no clear difference in major outcomes among commonly used types for polypectomy.

“Electrosurgery is extensively used in endoscopic therapeutic procedures,” Dennis Yang, MD, of the Center for Interventional Endoscopy at AdventHealth, Orlando, Florida, and coauthors wrote in the update, published in Clinical Gastroenterology and Hepatology. “An understanding of the principles of electrosurgery is fundamental for its safe and effective use across the various applications of this technology in gastrointestinal (GI) endoscopy.”

The update, based on expert review and 13 best practice advice statements, synthesizes current evidence and practical considerations for physicians using electrosurgical units (ESUs) across therapeutic endoscopy. The authors noted that multiple variables, including device type, contact area, tissue composition, and operator technique, interact to determine tissue effect.

Adjusting generator settings alone may not reliably achieve the intended outcome. Current density, defined as current per unit area, plays a key role. Smaller contact areas, such as thin snares, increase current density and favor cutting, while larger contact areas reduce density and promote coagulation.

Polypectomy: No clear winner for current type

For colorectal polypectomy, the update authors reported that cut-predominant and coagulation-predominant currents can both be used without meaningful differences in major outcomes. In a randomized trial cited in the update, intraprocedural bleeding occurred more often with cutting current than coagulation current (17% vs 11%), but rates of severe adverse events (about 7% to 8% in both groups) and delayed bleeding (about 5% to 6%) were similar.

Complete resection and recurrence rates also did not differ between current types. However, the author's noted findings were generated using modern microprocessor-controlled ESUs, which adjust power output in real time based on tissue impedance. Results may not be generalizable to older systems. Technique and tissue characteristics remain critical modifiers of outcomes, reinforcing that device settings should be individualized during procedures, noted Dr. Yang and colleagues.

Hot snare preferred for large pedunculated polyps

The update authors recommend hot snare polypectomy for large pedunculated polyps, which often contain sizable feeding vessels. Electrosurgical current facilitates vessel sealing and reduces immediate bleeding risk compared with cold snaring. For these lesions, a coagulation-predominant waveform may help seal vessels before transection. Proper snare positioning at the mid-stalk rather than near the base is also emphasized to limit thermal injury to the colonic wall.

Thermal margin ablation reduces recurrence

After piecemeal endoscopic mucosal resection (EMR), thermal ablation of resection margins significantly lowers recurrence risk. Recent trials cited in the review show recurrence rates can be reduced to less than 5% at first follow-up when techniques such as snare tip soft coagulation (STSC) or argon plasma coagulation (APC) are applied to normal-appearing margins.

STSC and APC appear similarly effective, though STSC may be more cost-efficient. The update authors cautioned that thermal therapy should be limited to normal margins, with visible residual neoplasia treated separately.

Environment and technique 

The environment you’re working in—gas verus fluid—changes how electrosurgery works. In saline, electricity flows more easily, so the energy spreads out and produces more coagulation rather than cutting. Because of this, endoscopists often need to use higher power settings to get a cutting effect. In the same way, the shape of the electrical waveform also affects the result. Settings with a higher duty cycle tend to cut tissue, while higher peak voltages can penetrate deeper and create stronger effects, even when the tissue has higher resistance.

Tissue resistance varies across the GI tract and changes during procedures, particularly as tissue desiccates. Modern ESUs compensate for these changes, but real-time adjustment by the endoscopist remains necessary, noted the update authors.

Safety practices and complications

Although ESU-related complications are uncommon, most adverse events are linked to operator or device factors. Recommended safety practices include preprocedural timeouts, proper placement of dispersive electrodes, and closed-loop team communication.

Extra care is required for patients with implanted heart devices, as electrosurgical currents can interfere with how the devices operate. Strategies include positioning return electrodes to avoid current pathways near devices and using bipolar energy when feasible.

Soft coagulation works well to stop bleeding, but using too much can cause deeper heat damage and may even lead to a delayed perforation. The authors recommended precise targeting, minimal contact area, and short activation times to mitigate risk.

Adjunct techniques and advanced procedures

Hot forceps avulsion was presented as an effective adjunct for fibrotic, non-lifting lesions, particularly in the colon. This technique uses a concentrated electrical current applied in short bursts to remove attached tissue while limiting damage to surrounding areas.

For argon plasma coagulation (APC), physicians must balance power and gas flow. Too much fluid flow can spread out the current and make it less effective, while poor bowel preparation can increase the risk of rare but serious complications, such as a colonic explosion.

In endoscopic retrograde cholangiopancreatography, optimal sphincterotomy depends more on technique than energy setting. Using light contact and positioning the wire correctly helps achieve effective cutting while lowering the risk of pancreatitis.

Electrosurgery is not a “set-and-forget” technology. Outcomes depend on a dynamic interplay of generator settings, device choice, tissue characteristics, and operator technique, concluded the update authors.

The update was commissioned and approved by AGA. Dr. Yang and several authors report consulting relationships with device manufacturers, including Boston Scientific, Olympus, Medtronic, and others.