Suction blisters of the skin: a compartment with physiological, interstitium-like properties.

In six young men without known skin disease we evaluated whether mild suction to the skin significantly alters the properties of the underlying capillaries or whether suction blisters can be regarded as an interstitium-like compartment with dynamic physiological properties. Instead of the usual technique where the tracer is administered intravenously prior to the suction, we postponed the administration of the tracer (99mTc-DTPA) to 15 min after the suction blisters had been formed on the abdominal skin. We found that the final slope of average interstitium 99mTc-DTPA was almost parallel to that of the final slope of 99mTc-DTPA in the blister fluid (r = 0.917). During the period 120-240 min after the injection where the final slopes could be defined, the ratio between the amount of 99mTc-DTPA present in the interstitium and the amount of 99mTc-DTPA present in a blister fluid volume equal to interstitial fluid volume was 1.3. It is concluded that suction blisters of the skin behave like a dynamic interstitium-like compartment.