Percutaneous Electrical Nerve Field Stimulation for Drug-Refractory Pediatric Cyclic Vomiting Syndrome.

BACKGROUND: Cyclic vomiting syndrome (CVS) is a disabling condition frequently refractory to pharmacologic therapy. The aim of this study was to evaluate the effects of noninvasive, auricular percutaneous electrical nerve field stimulation (PENFS) as prophylactic therapy for pediatric CVS. METHODS: Children 8-18 years with drug-refractory CVS were prospectively enrolled from a tertiary care CVS clinic. Subjects received 6 consecutive weeks of PENFS. CVS severity was quantified by episode frequency and duration score (range 0-25) at baseline and at extended follow-up (4-6 months after end of therapy). Response was classified as ≥50% improvement in either frequency or duration of attacks at extended follow-up. Subjects also completed validated surveys of nausea, disability, and global response. RESULTS: Thirty subjects completed the study. Median (interquartile range, IQR) age was 10.5 (8.5-15.5) years; 60% were female. At follow-up, 80% met criteria for treatment response with a median (IQR) response duration of 113 (61-182) days. The frequency-duration score improved from baseline median (IQR) 12.0 (9.0-16.0) to 3.0 (1.0-6.0) at follow-up, P < 0.0001. Median (IQR) nausea and disability scores decreased from baseline to week 6: 2.1 (1.3-2.7) to 0.9 (0-1.6), P = 0.003 and 47.5 (41.0-53.0) to 38.0 (16.0-51.0), P = 0.001, respectively. At end of therapy, 66% and 55% patients reported global response of at least "moderately better" and "a good deal better," respectively. There were no serious side effects. CONCLUSIONS: This study suggests long-term benefits of PENFS for children with CVS. PENFS improves several disabling aspects of CVS, including episode frequency, duration, and functional disability.