Variability of near-fainting responses in healthy 6-16-year-old subjects
de Jong-de Vos Van Steenwijk, C.C.E.
TNO Biomedical Instrumentation
1. Fainting is a common phenomenon in young subjects, but the final events before the actual faint are not well known. The aim of the present study was to study the inter-individual variability of haemodynamic events associated with near-fainting in children and teenagers. 2. Sixty-eight healthy subjects (aged 6-16 years) performed a 70°tilt-up test with intravascular instrumentation for 5 min. Responses in 29 near-fainting subjects were analysed and compared with 39 non-fainting subjects. Arterial pressure was measured by Finapres. Left ventricular stroke volume was computed from the pressure pulsation wave-form. 3. Inability to maintain vasomotor tone was mechanism underlying near-fainting in the majority of near-fainting subjects. The three classical haemodynamic responses (vasovagal, vasodepressor and vagal) could be recognized, but large individual differences were found. After tilt back, blood pressure in near-fainters showed a mirror response to the stage before tilt-back; blood pressure gradually increased and was normal at 1 min after tilt-back. 4. The variability in haemodynamic responses on approach of an orthostatic faint is wide in the young.
To reference this document use:
Blood Pressure Monitoring, Ambulatory
Signal Processing, Computer-Assisted
Clinical Science, 93 (3), 205-211