The effect of polyneuropathy on foot microcirculation in Type II diabetes

Abstract

Aims/hypothesis. The aim of this study was to investigate the influence of peripheral polyneuropathy (PNP) on skin microcirculation and foot swelling rate in the feet of patients with Type II (non-insulin-dependent) diabetes mellitus. Methods. 38 Type II diabetic patients, 24 with PNP (PNP+), 14 without PNP (PNP-), and 16 healthy control subjects were studied, first supine and subsequently sitting with the foot dependent for 50 mn.Results. In patients with PNP, foot skin temperature was higher, (p<0.04) and capillary blood cell velocity (CBV, nailfold capillary microscopy), was lower compared to patients without PNP (222 vs 313 µm/s respectively, p<0.03). Compared to the control subjects, the percentage reduction in skin blood flux, (LDF, laser-Doppler fluxmetry), after 10 min was higher in the PNP-and PNP+ patients (3% vs 18% and 26% respectively, p<0.02). These disturbances were most pronounced in PNP+ patients with a history of a foot ulcer. Foot swelling rate (mercury strain gauge plethysmography) in the first 10 min of dependency, was lower in patients with PNP+ compared to the control subjects (0.00165 vs 0.00286 ml·100 ml -1 s respectively, p<0.01). In addition, we found a negative correlation (r=-0.41; p<0.01) between Valk-score (severity of PNP) and FSR. Conclusion/interpretation. Type II diabetes PNP is associated with multiple abnormalities in the (skin) microcirculation of the foot, characterised by reduced capillary blood flow, an enhanced reduction in skin blood flux and impaired fluid filtration after sitting up. The most severe abnormalities were observed in patients with a history of foot ulceration. [Diabetologia (2002[Diabetologia ( ) 45:1164[Diabetologia ( -1172

The Effect of Shear Force on Skin Viability in Patients with Type 2 Diabetes

“…Our data suggest that increased susceptibility of diabetic tissues to noxious stimuli might be more related to impaired vasodilator capacity of the microcirculation than to increased vulnerability per se. Interestingly, the amount of DNP did not affect the immunological or microvascular skin response after the application of shear in our study; in contrast, diabetic neuropathy did affect vasodilator response to local pressure in previous studies [20, 32]. We measured the skin responses to shear in the forearm, and therefore, we cannot exclude that different results might have been obtained when measurements were performed in the foot (which was technically not feasible).…”

“…The diagnosis of DNP was based on a standardised clinical neurological examination (CNE), and its presence as well its severity was assessed using a validated scoring system [20]. This clinical scoring system corresponds well with the results of the neurophysiological examination and has acceptable sensitivity and specificity for the diagnosis of DNP when a cut-off point > 4 is used [21].…”

Infrared Thermography and Vascular Disorders in Diabetic Feet

“…These changes reportedly lead to capillary hypoperfusion, with likely impairment of wound healing. 34-36…”

Skin Blood Flow in the Upper and Lower Extremities of Diabetic Patients with and without Autonomic Neuropathy

“…To the best of our knowledge, no comparison has been done among all four extremities so far. The overview of the baseline data from the studies applying provocational tests shows that most of the authors have not found any difference in the basal cutaneous blood flow between diabetic patients and healthy controls [7, 8, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39]. The majority of the published data is on mean blood flow, not estimating the contribution of different frequency components.…”