Correlations between nerve function and tissue oxygenation in diabetic patients: further clues to the aetiology of diabetic neuropathy?

Transcutaneous oxygen, laser Doppler flowmetry, peroneal nerve motor conduction velocity and skin temperature were assessed in both legs of 34 diabetic patients, who had a mean age of 41 (range 29-77) years, and diabetes duration of 21 (3-34) years. Transcutaneous oxygen significantly correlated with peroneal nerve motor conduction velocity (r = 0.59 p < 0.001) and laser Doppler flowmetry (r = 0.7 p < 0.001). Laser Doppler flowmetry correlated weakly with peroneal motor conduction velocity, (r = 0.34 p < 0.05). In each patient the leg with the higher transcutaneous oxygen (mean 70.2 +/- 9.3 (SD) mmHg) had a significantly higher peroneal motor conduction velocity (45.3 +/- 7.1 vs 41.5 +/- 6.3 m/s, p < 0.01), than the leg with the lower transcutaneous oxygen (61.0 +/- 11.9 mmHg), though no difference in skin temperature was observed, 31.4 +/- 0.4 vs 31.1 +/- 0.5 degrees C. We then assessed the potential for reversibility of conduction velocity deficits in ten non-diabetic patients, aged 59 (52-77) years, undergoing unilateral femoro-popliteal bypass, measuring transcutaneous oxygen, peroneal nerve motor conduction velocity and skin temperature pre- and 6 weeks post-surgery. In the control leg (unoperated) there was no significant change in transcutaneous oxygen (63.2 +/- 8.8 vs 63.0 +/- 4.6 mm Hg), peroneal nerve motor conduction velocity (45.1 +/- 7.8 vs 43.4 +/- 7.2 m/s) or skin temperature (30.8 +/- 1.3 vs 30.2 +/- 1.2 degrees C) after surgery (all NS).(ABSTRACT TRUNCATED AT 250 WORDS)