ABSTRACT
Assessment of patient fluid requirements is often difficult. Previous basic as well as clinical studies have suggested that interstitial fluid pressure (IFP) correlates with interstitial fluid volume and can be measured with a catheter placed in the subcutaneous space. We constructed a simple device to monitor IFP. The mean IFP for 7 healthy volunteers was -1.19 mmHg. IFP was measured in 25 patients at presentation and as clinical status evolved. Patients were classified as hypervolemic, normovolemic, or hypovolemic on the basis of their clinical status, the evolution of their condition, and laboratory and radiographic data. IFP correlation with assigned classification was statistically significant. The results suggest IFP can be measured readily and reliably in humans and is sensitive for reflecting the hydration of the interstitial compartment. This measure can assist in the determination of patient fluid requirements.
