Clinical application and research progress of extracellular slow wave recording in the gastrointestinal tract

Table 1 Milestone research of extracellular gastrointestinal slow wave recording

Ref.	Year	Research type	Methods	Part of GI	Major advances
Alvarez et al[6]	1922	Rabbits	Monopolar electrode	Small intestine	First record the SW
Alvarez[32]	1922	Human	EGG	Abdominal wall	First electrogastrogram recording
Code and Marlett[89]	1974	Dogs	Multi-electrode	Stomach	First report gastric arrhythmia
Code et al[29]	1975	Dogs	Multi-electrode	Stomach and small intestine	Define the MMC
Hinder and Kell[54]	1977	Human	Multi-electrode	Stomach	First locate the gastric pacemaker
Di Luzio et al[90]	1989	Human	MGG	Stomach and small intestine	Noninvasively investigate the activity of the GI system
Miranda et al[91]	1992	Human	ACB	Stomach	Study stomach emptying model
Bradshaw et al[92]	2003	Rabbits	MGG	Stomach	Investigate gastric electrical activity under normal and vagotomized condition
Corá et al[76]	2005	Human	ACB	Stomach	Obtain a comprehensive knowledge of the behavior of pharmaceutical forms in the GI tract
Lammers et al[93]	2008	Dogs	HR mapping	Stomach	First observe the spatial origin and propagation patterns of SW arrhythmias
Bradshaw et al[68]	2009	Human	MGG	Stomach	Obtain spatiotemporal parameters of the gastric SW
Du et al[62]	2009	Pigs	HR mapping	Stomach	Design a new sterilized PCB electrode
O'Grady et al[66]	2009	Pigs and human	HR mapping	Stomach	Design a novel laparoscopic device for HR mapping
O'Grady et al[55]	2010	Human	HR mapping	Stomach	The most comprehensive study of the gastric conduction system
Farajidavar et al[52]	2012	Dogs	Multi-wireless modules	Stomach	Design a bidirectional wireless system for SW recording
Calabresi et al[72]	2015	Rats	ACB	Stomach	Assess gastric motility
Gharibans et al[94]	2017	Electrophysiology model	HR-EGG	Stomach	Address the spatial limitations of the EGG
Gharibans et al[95]	2019	Human	HR-EGG	Stomach	Achieve comprehensive spatial analytics of gastric far-field gastric potentials

ACB: Alternate current biosusceptometry; EGG: Electrogastrogram; GI: Gastrointestinal tract; HR: High-resolution; MGG: Magnetogastrogram; MMC: Migrating motor complex; PCB: Printed circuit board; SW: Slow wave.

Table 2 Clinical research on gastrointestinal electrical stimulation

Ref.	Methods	Sample size	Indications	Location of GIES	Stimulation parameters	Duration	Results
Gastric electrical stimulation
McCallum et al[96]	Multicenter, double-blind, RCT	32	Idiopathic gastroparesis	Stomach	14 Hz, 5 mA, 330 μs	3 mo	Significant decrease in vomiting and days of hospitalization
Teich et al[97]	Prospective study	16 (children)	Chronic nausea andvomiting	Stomach	14 Hz, 5 V, 330 μs	0.5-23 mo	Significant improvement in severity and frequency of vomiting, frequency, and severity of nausea
Morales-Conde et al[98]	Randomized, multicenter trial	47	Obesity	Stomach	/	24 mo	Limited weight regain with strong safety outcomes
Ducrotte et al[99]	RCT	172	Refractory vomiting	Stomach	14 Hz, 5 mA, 330 μs	8 mo	Effectively reduced the frequency of refractory vomiting in patients with and without diabetes, although it did not accelerate gastric emptying or increase the quality of life
Intestinal electrical stimulation
Norton et al[100]	RCT	90	Fecal incontinence	Anus	35 Hz, 300 ms	8 wk	Improved bowel control to a modest extent
Daram et al[101]	Case report	1	Roux stasis syndrome	Jejunum	14 Hz, 5 mA, 330 μs	5 d	Effective relief of the symptom of stasis post-Roux-en-Y anastomosis
Cadeddu et al[102]	Randomized trial	81	Idiopathic constipation	Anus	2 Hz, 30-35V, 360-960 μs	6 times	Continuous improvement of constipation symptoms and anorectal function
Nerve electrical stimulation
Fassov et al[103]	RCT	20	IBS	Sacral nerve	14 Hz, 0.1-4.0 V, 210 μs	3 wk	Reduced symptoms of diarrhea-predominant and mixed IBS
Stakenborg et al[104]	Pilot study	18	Post-colectomy surgery	Abdominal vagus nerve	5, 20 Hz, 2.5 mA, 0.5, 1, 2 ms	2 times (preparation, postoperation)	Inhibition of IL-6 and IL-8 induced by lipopolysaccharide to prevent postoperative intestinal obstruction
Zhang et al[105]	Pilot study	42	Major abdominal surgeries	Acupoints ST36 and PC6	25 Hz, 2-10 mA, 0.5 ms	3 d	Improved major postoperative symptoms
Teckentrup et al[106]	RCT	22	Healthy subjects	Vagus nerve	25 Hz, 0.3-0.9 mA	2 d	Reduced the frequency of gastric myoelectricity and did not affect resting energy consumption

GIES: Gastrointestinal electrical stimulation; IBS: Irritable bowel syndrome; IL: Interleukin; RCT: Randomized controlled trial.