1. Transient hyperaemic response to assess vascular reactivity of skin; effect of locally iontophoresed sodium nitroprusside† 
V.L. Webster, R.P. Mahajan 
British Journal of Anaesthesia 
Volume 89, Issue 2, Pages (August 2002)
DOI: /bja/aef188
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

2. Fig 1
A custom-made perspex iontophoresis chamber specifically designed to allow simultaneous administration of drugs by iontophoresis and measurement of skin blood flow flux by the laser Doppler probe. The hole into which the drug is pipetted contains an inert platinum wire to serve as one of the electrodes during iontophoresis. An electrocardiogram electrode attached to the forearm 4 cm proximal to the chamber serves as the other electrode. T, temperature probe; D, Doppler probe; I, iontophoresis chamber; E, electrodes.
British Journal of Anaesthesia  , DOI: ( /bja/aef188)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

3. Fig 2
A chart recorder trace of one of the experiments. On the right-hand side are the two practice THR tests followed by the three baseline tests; all the baseline tests demonstrate hyperaemic response. Subsequently sodium nitroprusside was iontophoresed and this caused an increase in flow flux. Once the plateau was reached, three more tests were performed showing lack of hyperaemic response. P, practice tests; B, baseline tests.
British Journal of Anaesthesia  , DOI: ( /bja/aef188)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

4. Fig 3
Calculation of baseline (F1) and hyperaemic (F2) flow flux from biological zero. The THRR was calculated as F2/F1.
British Journal of Anaesthesia  , DOI: ( /bja/aef188)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

5. Fig 4
Changes in flow flux. Individual values of flow flux (measured in volts) before and after iontophoresis of sodium nitroprusside. The solid line shows mean change.
British Journal of Anaesthesia  , DOI: ( /bja/aef188)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions

6. Fig 5
Changes in THRR. Individual values of transient hyperaemic response ratio before and after iontophoresis of sodium nitroprusside. The solid line shows mean change.
British Journal of Anaesthesia  , DOI: ( /bja/aef188)
Copyright © 2002 British Journal of Anaesthesia Terms and Conditions