ORAL FLUID THERAPY - A PROMISING TREATMENT FOR VASODEPRESSOR SYNCOPE

Objectives: To investigate the predictive value of an intravenous flui d bolus during tilt table testing on clinical outcome and to evaluate if oral fluid therapy is an effective treatment for patients with vaso depressor syncope. Design: Retrospective cohort. Setting: Regional ped iatric cardiology outpatient clinic. Patients: Patients (N=58) with a positive baseline tilt table testing result who were treated with oral fluid therapy between February 1991 and March 1996. Interventions and Main Outcome Measures: Patients with a positive tilt table test resul t were given an intravenous bolus of isotonic saline solution. Respond ers were identified as having a negative tilt table test result after the bolus. Patients were prescribed a protocol of oral fluid therapy. Data were obtained from the medical record and a mailed survey. Result s: Of the 58 subjects, 90% had no recurrent syncope while receiving or al fluid therapy. During tilt table testing, the mean decrease in mean arterial pressure seen with symptomatic events was lower after the in travenous fluid. The heart rate, which dropped during the initial test s, increased during the tests after the intravenous bolus. In the nonr esponders, symptomatic episodes occurred significantly later in the ti lt table test when given fluids. The response to intravenous fluid bol us had a positive predictive value of 92% and a negative predictive va lue of 11% of clinical outcome. Conclusions: Our data suggest that ora l fluid therapy is an effective treatment for vasodepressor syncope in our population. Fluid bolus response during tilt table testing has a high positive but a low negative predictive value of response to oral fluid therapy. We now recommend oral fluid therapy as a primary interv ention and reserve tilt table testing for oral fluid therapy failures.