[Vascular exploration tests. Importance for the indications and monitoring of epidural medullary neuro-stimulation]

Abstract

The clinical diagnosis must be enriched by quantifiable parameters when a new therapeutic method must be tested. We analyse the role of vascular explorations for epidural stimulation and limb arteriopathies. Four different fields of investigations can be defined. Accuracy of the diagnosis: The tests are useful to rule out some differential diagnoses of arterial involvement, and to establish the functional severity (stage III). 1--Treadmill test: nonischemic pain is ruled out: the evolution can be followed up. 2--Doppler velocimetry demonstrates the extent of the dominant arterial involvement in cases of associated lesions. 3--Arterial pressure gradients: their presence demonstrates significant lesions and allows detecting the affected levels. Quantification of severity: After detecting the lesions, their impact must be appreciated. From a macrocirculatory point of view, the measurement of pressures and flow rates is more sensitive than the Doppler study. From a microcirculatory point of view, the tcpO2 is very useful. 1--Arterial pressure: measured in the ankle and the first toe. There are three degrees: non-threatening ischemia (pulsatile Doppler, distal pressure exceeding 30 mm Hg), threatening ischemia (non pulsatile Doppler, distal pressure exceeding 30 mm Hg), irreversible ischemia (no more pulse, no more capillary flow). If there are arterial calcifications, the pressure in the toe must be measured. 2--Arterial flow rate: the average flow rate may be preserved in an arteriopathy, while the pulsatile rate is already degraded. Non invasive electromagnetic or nuclear magnetic resonance flowmeters measure the total muscular flow. Laser Doppler shows the cutaneous flow rate. 3--The tcpO2: normally greater than 60 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)