Background: Gastric electrical stimulation (GES) has been shown in controlled trials to be effective for adults with refractory nausea and vomiting, but evidence of its benefit in children has thus far been limited to retrospective and prospective cohort studies. Our objective was to perform the first controlled trial of GES in children with refractory nausea and vomiting.
Methods: We performed a controlled, single-blinded trial of GES for children with refractory nausea and vomiting. Participants were recruited prior to starting a two-week trial of temporary GES delivered by a nasogastric pacing lead. Patient characteristics, medical history, diagnostic testing, clinical symptoms, route of nutrition, Symptom Monitor Worksheet (SMW), and nutrient drink test were collected at baseline. Participants and families were blinded to the status of the stimulator during the trial. After starting temporary GES, stimulators were turned off for the initial 3-4 days of the trial. Symptoms, SMW, and drink test were collected with the stimulator off (OFF). Stimulators were then turned on (10.0 volts for adolescents and 7.0 volts for children, pulse width 330 µs, frequency 28 Hz, 1 second on, 4 seconds off). Participants returned 3-4 days later and symptoms, SMW, and drink test were collected with the stimulator on (ON). Outcomes were compared between baseline and follow-up as well as with the stimulator OFF and ON.
Results: From October 2019-November 2023, 34 children with refractory nausea and vomiting were treated with temporary GES at our institution and 28 children (79% F, median age 16 years, IQR 14-17, range 4-19) participated in the trial. Prior diagnoses included gastroparesis (89%), functional dyspepsia (32%), cyclic vomiting syndrome (7%), and rumination syndrome (7%). Comorbid conditions included postural orthostatic tachycardia syndrome (43%), anxiety (25%), Ehlers-Danlos syndrome (18%), and depression (11%). Most children (75%) required supplemental nutrition, with 68% on tube feeding and 11% on parenteral nutrition. As shown in Table 1, symptom severity based on SMW total score improved from baseline both while OFF (35.5 vs. 25.5, p=0.001) and ON (35.5 vs. 21, p<0.001), but SMW was improved when ON compared to OFF (p=0.02). The maximum volume that participants were able to drink as measured by nutrient drink test was also improved from baseline both while OFF (90 ml vs. 105 ml, p=0.02) and ON (90 ml vs. 120 ml, p=0.002), but again the volume was greater when ON compared to OFF (p=0.02). 23/28 (82%) experienced significant clinical improvement during the trial and underwent implantation of the stimulator.
Conclusion: In this controlled trial of GES for children with refractory nausea and vomiting, children experienced greater improvement in symptoms and oral intake with GES compared to sham stimulation.

Table 1: Comparison of patient outcomes at baseline and follow-up time points. Each item of the Symptom Monitor Worksheet is scored 0-4 with higher scores indicating worse severity or frequency.