Functional claudication distance: a reliable and valid measurement to assess functional limitation in patients with intermittent claudication

BACKGROUND: Disease severity and functional impairment in patients with intermittent claudication is usually quantified by the measurement of pain-free walking distance (intermittent claudication distance, ICD) and maximal walking distance (absolute claudication distance, ACD). However, the distance at which a patient would prefer to stop because of claudication pain seems a definition that is more correspondent with the actual daily life walking distance. We conducted a study in which the distance a patient prefers to stop was defined as the functional claudication distance (FCD), and estimated the reliability and validity of this measurement. METHODS: In this clinical validity study we included patients with intermittent claudication, following a supervised exercise therapy program. The first study part consisted of two standardised treadmill tests. During each test ICD, FCD and ACD were determined. Primary endpoint was the reliability as represented by the calculated intra-class correlation coefficients. In the second study part patients performed a standardised treadmill test and filled out the Rand-36 questionnaire. Spearman's rho was calculated to assess validity. RESULTS: The intra-class correlation coefficients of ICD, FCD and ACD were 0.940, 0.959, and 0.975 respectively. FCD correlated significantly with five out of nine domains, namely physical function (rho = 0.571), physical role (rho = 0.532), vitality (rho = 0.416), pain (rho = 0.416) and health change (rho = 0.414). CONCLUSION: FCD is a reliable and valid measurement for determining functional capacity in trained patients with intermittent claudication. Furthermore it seems that FCD better reflects the actual functional impairment. In future studies, FCD could be used alongside ICD and ACD

Blutvolumenbestimmung in definierten Körperregionen mit 113mIn-(III)-chlorid

ZusammenfassungIn Kombination mit verschlußplethysmographischen Messungen kann bei gleichzeitiger Anwendung von 118mIn das Blutvolumen von Körperregionen und die Venendistensibilität bestimmt werden. Die hohen Impulsraten erlauben eine sichere Erfassung von kleinen Volumenänderungen nach Gabe von beta-stimulierenden oder -blockenden Substanzen. 113mIn wurde direkt als Chlorid intravenös injiziert. Bei venösen Drucken bis zu 30 mm Hg konnte kein Austritt aus den Gefäßen festgestellt werden. Im Laufe von 2 Stunden kam es zu einer geringen Aktivitätsanreicherung in der Leber. Da die Einzelmessungen nur wenige Minuten dauern, ist eine Beeinflussung der Ergebnisse nicht zu erwarten. Das TBV kann aber wegen geringer Abnahme der Plasmakonzentration - die durch die Zunahme in der Leber bedingt ist - nicht mit dieser einfachen Methode gemessen werden.</jats:p