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document
Effect of nitric-oxide-generating system on microcirculatory blood flow in skin of patients with severe Raynaud 's syndrome : a randomised trial . BACKGROUND Patients with Raynaud 's syndrome have abnormal digital vasoconstriction , which may be secondary to impaired synthesis of , or impaired sensitivity to , nitric oxide . We studied the effect on microcirculation of a nitric-oxide-generating system applied topically to the finger and forearm of healthy volunteers and patients with primary Raynaud 's syndrome . METHODS We did a single-blind , randomised , placebo controlled , cross-over study of the microcirculatory response to topical application of a nitric-oxidegenerating gel in 20 patients with severe Raynaud 's syndrome , and ten healthy volunteers . We prepared the nitric-oxide-generating system by mixing a solution of KY jelly and sodium nitrite ( 5 % weight/volume ) , with a solution of KY jelly and ascorbic acid ( 5 % weight/volume ) . About 0.5 mL of each solution was separately applied to the skin of the forearm ( 3 cm2 ) , and then mixed with a sterile cotton bud . A similar procedure was done simultaneously on the other arm with KY jelly only ( placebo ) . The procedure was then repeated on the finger pulps . Changes in skin microcirculatory volume and flux were measured bilaterally by infrared photoplethysmography and laser doppler fluxmetry , respectively . FINDINGS In the forearm , blood flow increased significantly after application of the active gel both in patients with Raynaud 's syndrome ( microcirculatory volume from mean area under the curve 98 [ SE 14 ] to 1024 [ 130 ] ; microcirculatory flux from 5060 [ 462 ] to 74,800 [ 3940 ] ) and in healthy controls ( volume from 85 [ 19 ] to 1020 [ 60 ] ; flux from 4420 [ 435 ] to 84,500 [ 7000 ] ) . In the fingers , although baseline blood flow was lower in patients than in controls , both groups showed increases with application of active gel ( volume from 1100 [ 194 ] to 3280 [ 672 ] and 2380 [ 441 ] to 6160 [ 1160 ] , respectively ; flux from 33,400 [ 4200 ] to 108,000 [ 13,600 ] and 52,000 [ 8950 ] to 185,000 [ 19,500 ] ) . Increases in blood flow with placebo gel were not significant . No adverse effects were reported . INTERPRETATION In primary Raynaud 's syndrome , topical application of a nitric-oxide-generating system can stimulate an increase in both microcirculatory volume and flux .
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Intervention_Pharmacological
nitric-oxide-generating system
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Intervention_Pharmacological
nitric-oxide-generating system
2049
Intervention_Pharmacological
nitric-oxidegenerating gel
2050
Intervention_Pharmacological
nitric-oxide-generating system
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Intervention_Pharmacological
KY jelly and sodium nitrite ( 5 % weight/volume ) , with a solution of KY jelly and ascorbic acid
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Intervention_Pharmacological
applied to the skin of the forearm
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Intervention_Control
KY jelly only ( placebo )
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Intervention_Pharmacological
nitric-oxide-generating system
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Outcome_Other
microcirculatory blood flow
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Outcome_Other
microcirculatory response
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Outcome_Mortality
Changes in skin microcirculatory volume and flux
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Outcome_Mortality
blood flow
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Outcome_Mental
baseline blood flow
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Outcome_Mental
flux
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Outcome_Other
blood flow
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Outcome_Adverse-effects
microcirculatory volume and flux .