Predicting amputation in severe ischaemia. The value of transcutaneous PO2 measurement

Abstract

The predictive value of the pedal transcutaneous oxygen tension (tcPO2) and of the distal systolic blood pressure (SBP) in forecasting the necessity for later amputation has been studied in 26 patients suffering from severe chronic ischaemia of the lower limbs. In all these patients vascular surgery had failed or not been possible, and they were threatened by amputation; they suffered from trophic lesions, or pain at rest, or both. The great toe SBP averaged 10 mmHg (range 0 to 60 mmHg) and the pedal tcPO2 10 mmHg (range 2 to 45 mmHg). After six minutes of oxygen inhalation there was an increase in pedal tcPO2 of 9 mmHg (0 to 50 mmHg). After a follow-up period averaging 7 months (range 10 days to 13 months), 13 patients underwent an amputation and nine (five of whom had been amputated) died. The great toe SBP in the patients who required amputation was initially lower than in those who did not. The pedal tcPO2 also was lower in amputated than in non-amputated patients. There was no amputation in the group showing an increase of at least 10 mmHg after six minutes of oxygen inhalation; and conversely, all patients in whom the pedal tcPO2 increased less than 10 mmHg were amputated. Thus increase in the pedal tcPO2 after oxygen inhalation appears the best criterion for estimating the prognosis of severely ischaemic limbs.

Efficacy of Fifth Metatarsal Head Resection for Treatment of Chronic Diabetic Foot Ulceration

“…This method of evaluation, although arguably not as sensitive as other noninvasive methods, such as transcutaneous oximetry, segmental extremity pressure studies, or laser Doppler flowmetry, has the benefit of having been performed systematically on all of the patients in this study. [16][17][18][19] All procedures performed fell into diabetic foot surgery class 3 (curative) using the classification described by Armstrong and Frykberg. 10 The fifth metatarsal head resections were performed by one of two attending surgeons.…”

Measurement of critical lower limb tissue hypoxia by coupling chemical and optical techniques

“…Light at visible wavelength (450-700 nm) is strongly attenuated in tissue and, as a result, can only penetrate a maximum distance of a few millimetres [20]. However, the absorption of light by the tissue chromophores is significantly lower at near-infrared wavelengths (700-1000 nm) and, with sensitive detectors, it is possible to detect light that has traversed up to 80 mm of tissue [18]. There are three main compounds whose nearinfrared absorption characteristics vary with their oxygenation status.…”

“…Measurement of Po 2 (partial pressure of O 2 ) in tissues by surface probes has been used in the past to estimate the level of amputation required in ischaemic limbs with various degrees of success [16][17][18]. The system used at the time employed multiwire surface electrodes covering a wide surface area which resulted in heterogeneous values due to high mixed venous Po 2 [19].…”

Clinical Efficacy of the First Metatarsophalangeal Joint Arthroplasty as a Curative Procedure for Hallux Interphalangeal Joint Wounds in Patients with Diabetes

“…Diagnosis of ischemia was standardized in the facility where data were abstracted and was made by the absence of more than one foot pulse or a nonaudible signal on Doppler ultrasonography of the dorsalis pedis or posterior tibial pulses on the affected extremity. This method of evaluation, although arguably not as sensitive as other noninvasive methods such as transcutaneous oximetry, segmental extremity pressure studies, or laser Doppler flowmetry, has the benefit of having been performed systematically on all patients in this study (23)(24)(25)(26).…”