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 non-invasive, 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: 30 subjects completed the study. Median (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.