Annual Meeting of the North American Society for Pediatric Gastroenterology and Nutrition; Orlando, October 22-24, 1998
Sympathovagal Balance of Pediatric Patients with Cyclic Vomiting
Background: Cyclic vomiting Syndrome is characterized by "fits of vomiting, which recur after intervals of uncertain length" (Forbes, 1995). Most children with CVS are refractory to usual antiemetics. Successful treatment is hampered by the lack of understanding about the pathogenesis of CVS. In previous work we found an increase in sympathovagal autonomic balance (the ratio between the sympathetic and parasympathetic activity) during active vomiting state as compared to the passive state or interval between episodes. Purpose: To determine whether there is a difference in sympathovagal balance in children with CVS during their passive states compared to normal children.
Methods: ECG recording was done in 20 minute intervals repeated once for each patient. The heart rate variability of the ECG recording was analyzed by Fast Fourier Transformation and put through an algorithm which creates a power spectrum of heart rate variability reflecting sympathovagal balance. Results of 9 CVS patients were compared to those obtained for 38 normal children used as controls. Statistical analysis was done using a one-way ANOVA. Population - 9 CVS patients studied, 6 male 3 female. Age range 6 to 16. Median Age 10.
Results: There was significant increase in sympathovagal balance in the 9 CVS patients studied when compared to the 38 normal children (df=60, p-value <0.001). Further analysis demonstrated a higher sympathetic drive (p-value) and lower parasympathetic influence (p-value) for CVS patients compared to controls.
Conclusion: The preliminary data on the study suggest that not only do CVS children have more sympathetic outflow but also have insufficient modulation by the parasympathetic nervous system evidence between bouts of vomiting.
Esophagus/Stomach© 1998 Lippincott Williams & Wilkins, Inc.