Effects of Intermittent Intravenous Saline Infusions in Patients with Medication-refractory Postural Tachycardia Syndrome

Background: The postural tachycardia syndrome (POTS) is a heterogeneous group of disorders that results in symptoms of orthostatic intolerance. Excess blood pooling has been observed to cause low effective circulating volume in the central vasculature. Consequently, acute volume loading with IV saline has emerged as a potential strategy for clinical intervention. We evaluated the impact of acute volume loading on both the signs and symptoms of patients suffering from POTS.

Methods: Fifty-seven subjects screened from our population of POTS patients and assenting to participation were administered the two surveys by telephone. Subjects completed each survey twice, before, and after initiating IV hydration therapy. The Orthostatic Hypotension Questionnaire (OHQ) was used to assess change in clinical symptomatology, while the short form 36 health survey (SF-36) was employed to assess the impact of IV saline infusion on quality of life.

Results: Fifty-seven patients were included in the analysis. The average number of medications trialed before referral for IV hydration was 3.6 ± 1.7 medications. Saline infusions occurred with mean frequency of 11.3 ± 8.5 days and at a mean volume of 1.5 ± 0.6 l per infusion. The mean change of the OHQ was 3.1 ± 0.3 (95% CI 2.6-3.7; P < 0.001), with significant improvement in all the composite scores. The mean change in the SF-36 form was 19.1 ± 2.7 (95% CI -24.6 to -13.6; P < 0.001).

Conclusions: Intermittent IV infusions of saline dramatically reduce symptoms and improve quality of life in patients suffering from POTS. Further work should explore its efficacy as a bridge study for patients of high symptomatic severity.