Gastric electrical stimulation: An emerging therapy for children with intractable gastroparesis

Table 1 Synopsis of commonly used prokinetic agents for gastroparesis[7]

Prokinetic agents	Mechanism	Comments/Limitations
Erythromycin	Motilin receptor agonist	QT interval prolongation
Azithromycin		Tachyphylaxis
		Antibiotic and bacteria resistance
Metoclopromide	D2 antagonist (central/peripheral)	Extrapyramidal symptoms (e.g., tardive dyskinesia, dystonia). Can not use > 12 wk
	5-HT3 antagonist	QT interval prolongation
	5-HT4 agonist	FDA approved for adults
Domperidone	Peripheral D2 antagonist	QT interval prolongation
		Not approved in United States. Only available through IND
Baclofen	GABAB receptor agonist that inhibits transient lower esophageal sphincter relaxation. Increases gastric emptying	Muscle weakness, dizziness
		Very limited data, as trial was limited to a gastroesophageal reflux patients

FDA: Food and drug administration; D₂: Dopamine receptor 2; 5-HT₃ and 5-HT₄: 5-hydroxytryptomine receptor 3 and 4; GABA_B: Gamma-amino-butyric-acid B receptor; IND: Investigational new drug.

Table 2 Alternative therapies for refractory gastroparesis[2,3,19,21,22]

Therapy	Mechanism/Indication	Comments
Botulinum Toxin	Endoscopic intra-pyloric injection of botulinum toxin to relax the pylorus	Requires frequent injections
		No improvement in long term symptoms
Enteral tube feeds	Unintentional loss of 10 % or more of the body weight during a period of 3-6 mo, Refractory symptoms	Mechanical complications: Obstruction, displacement, or dislodgement of the tube.
		Gastrointestinal complications: formula intolerance, diarrhea, constipation,
		Hinders normal lifestyle and quality of life
Gastrostomy tube	May be used for venting of secretions to decrease vomiting and fullness	Poor choice for feeding due to delayed gastric emptying
PEG-J tube	Allows the patient to vent gastric secretions to decrease/prevent persistent emesis. Provides jejunal feedings	Migration of the J-tube extension into stomach
		Pyloric obstruction from J-tube
Jejunostomy tube	Stable access for reliable jejunal nutrient	Cannot vent stomach
	Delivery Avoids gastric penetration
Dual G and J tube	Two sites-one for venting and one for enteral nutrition	Increased risk of leakage, infection Cosmetic issues
Parenteral Nutrition	Indicated due to intolerance to enteral feeds	Central venous access required.
		High risk of line infections
		Time consuming, expensive, and intrusive into daily routines
		Anesthesia complications
Surgical Options
Pyloroplasty	Surgical procedure used to widen the pylorus	Radical approach
		Limited success
		Surgical and anesthesia complications
Gastrectomy	After failed medical therapy with severe symptoms	Palliative approach
		Nausea continues to be a problem
		High risk of surgical and anesthesia complications.
		Not reversible

PEG: Percutaneous endoscopic gastrostomy; PEG-J: Percutaneous endoscopic gastrostomy with jejunal extension tube.

Table 3 Comparison of pediatric studies on gastric electrical stimulation

Ref.	Method	Sample Size	Duration	Findings
Islam et al[28]	Prospective study on children with chronic nausea and vomiting	9	8-42 mo	7 of the 9 patients reporting sustained improvement in symptoms and improved quality of life
Islam et al[5]	Retrospective review in children less than 18 years with diagnosis of gastroparesis	97	10 yr	A significant reduction in all individual symptoms as well as the total symptom score at 1, 6, 12, and 12 mo. Recurrence of symptoms leading to device removal occurred in 7 cases. Forty-one patients had continued improvement in symptoms for over 12 mo, with a mean follow up of 3.5 years
Lu et al[29]	Retrospective review on patients with functional dyspepsia	24	6-8 mo	Significant improvements were seen in multiple areas of the PedsQL, including stomach pain/upset, food/drink limits, heartburn/reflux, gas/bloating, patient worry, medication tolerance, and constipation
Teich et al[35]	Prospective study on children with chronic nausea and vomiting refractory to medical therapy and met ROME III criteria for functional dyspepsia	16	0.5-23 mo	Significant improvement in severity and frequency of vomiting, frequency and severity of nausea. Also showed decrease in dependence on enteral/parenteral nutrition
Elfvin et al[36]	Retrospective review on children with nausea and vomiting	3	12-40 d	Favorable response to temporary percutaneous gastric electrical stimulation with greater than 50% vomiting reduction
Hyman et al[26]	Case report on a 7 years old boy with intractable visceral pain and gastroparesis and failure to thrive	1	37 mo	Reduction in pain, retching and vomiting. Successful initiation of enteral feeds and meeting caloric requirements