[Follow-up study, using dynamic transcutaneous oximetry in 17 patients with stage II Leriche and Fontaine occlusive arterial disease of the lower limbs]. / Suivi par oxymétrie transcutanée dynamique de 17 malades avec artériopathie oblitérante des membres inférieurs au stade II de Leriche et Fontaine.

We evaluated the value of dynamic transcutaneous oxygen pressure measurement (TcPO2) in 17 patients with stage II occlusive arterial disease of the lower limbs treated with exercise only. We studied 17 patients (15 men, two women) with an average age of 63 years (range 39-80 years). Claudication perimeter and dynamic TcPO2 were evaluated before and after 6 month walking exercise and tabac stopping. Four different sites of TcPO2 were studied: precordium (reference probe), thigh, calf and foot in the dorsal recumbent position after 30 minutes rest, during a standardised exercise stress test at 50 watts and during the recovery phase. The results were expressed as ratio of tissue oxygenation (RTO): thigh, calf or foot TcPO2/precordial TcPO2 x 100 in order to take into account the patients cardiorespiratory status and adaptation to exercise. Claudication perimeter was 255 m +/- 221 before 6 months exercise and 835 m +/- 539 after (P < 0.01). The duration of significative ischemia was significantly reduced after 6 months exercise (P = 0.02 calf, P < 0.01 foot). Dynamic transcutaneous oxymetry would therefore seem to be a useful method of assessing stage II occlusive peripheral arterial disease and the topography of tissue hypoxia. It could be valuable in orientating treatment and the first method to provide and objective evaluation of the efficacy of medical or surgical treatment.

[Study of static transcutaneous oximetry before amputation in patients with arteritis]. / Etude de l'oxymétrie transcutanée statique avant amputation chez l'artéritique.

Transcutaneous oximetry has been used to define the level of amputation in arteritic patients, with discrepant results. We have studied preoperative statix oximetry in 33 arteritic patients at the Leriche-Fontaine Stage IV, who underwent 36 amputations (thighs = 6, Legs+Symes = 14, transmetatarsal = 7, toes = 9). Oximetry included the measurement, at the level of amputation, of the transcutaneous partial oxygen pressure (tc pO2), of the tissue oxygenation ratio (TOR), preferably with a precordial electrode, of the tc pO2 gain after oxygen inhalation and of the gain ratio with the reference electrode. Two patients died postoperatively, the amputation stump did not heal in another 8 patients. The tc pO2 value was 36.6 +/- 16.2 mm Hg in the healed group and 21.1 +/- 19.9 mm Hg in the non healed group. The TOR respectively was 71.2 +/- 32.7% and 38.6 +/- 29.9% in these two groups. These differences were statistically significant. The difference between the two groups in the measurements made after the oxygenation test was not statistically significant. With a tc pO2 threshold at 26 mm Hg, the sensitivity was 73% and the specificity 75%, the positive predictive value 90%, the negative predictive value 46% and the value of the test 73.5%. The thresholds calculated to be 56% for TOR, 11 mm Hg for the gain and 32% for the gain ratio, did not improve the performances of oximetry. In our study, the tc pO2 was the parameter that best allowed predicting healing was obtained with smaller values than the threshold. Other elements such as the general condition and diabetes have played a role in the prognosis.