Performance of finger systolic blood pressure measurement to detect digital occlusive arterial disease in systemic sclerosis

Microvascular abnormalities induced by hand-transmitted vibration reflects in finger systolic blood pressure: a cross-sectional study in China

OBJECTIVE

Local vibration can cause microcirculatory abnormalities such as blood stasis and symmetrical intermittent digital artery vasospasm. Finger SBP (FSBP) measurement is a potential way of assessing vascular components. This study aims to comprehensively investigate the relationship between the occurrence of the vibration-induced white finger (VWF) and changes in FSBP and then set the application value of FSBP measurements in the early diagnosis of VWF.

METHODS

All samples were judgmental sampling from one factory. Totally 50 patients with VWF were the case group, while 50 without occupational hand-transmitted vibration exposure were the control group. FSBP measurements and epidemiological feature investigations were taken.

RESULTS

There were significant reductions in FSBP level and %FSBP index at both 10 °C and 30 °C in fingers reported VWF ( P  < 0.05). The %FSBP abnormal rate of the index, ring and little finger in the VWF group was higher than the control (44.00% vs. 18.00%, 78.00% vs. 26.00%, 64.00% vs. 8.00%). The %FSBP of the ring and little finger had a relatively high application value (area under curve = 0.902, 0.737), while their standard regression coefficients were -0.23 and -0.412. The diagnostic cutoff value of the ring finger was 77.60%, while the sensitivity and specificity were 86.67%.

CONCLUSION

FSBP measurements were proven helpful in monitoring and diagnosing VWF prospectively and proved to have great application value in our study. %FSBP of the ring finger was the appropriate diagnostic index in FSBP measurements, while its abnormal value could be set as 80.00%.

Ultrasound Classification of Finger Pulp Blood Flow in Patients With Systemic Sclerosis: A Pilot Study

OBJECTIVE

To define a semiquantitative classification of finger pulp blood flow (FPBF) and to evaluate whether this classification could be used to assess FPBF in healthy controls and in systemic sclerosis (SSc) patients.

METHODS

Thirty controls and 86 SSc patients were consecutively included. A classification of FPBF including 5 grades (from grade 0 [no signal] to 4 [signal detected on the entire finger pulp, including the subepidermal vascular network]) was evaluated. This classification was explored in basal conditions and after hand baths in hot and cold water in controls. Its relevance was also assessed at room temperature in SSc patients.

RESULTS

In controls, power Doppler ultrasonography (PDUS) of FPBF was improved after hot challenge (P = 0.024), whereas cold challenge decreased FPBF (P = 0.001). FPBF correlated with the vasodilation status assessed by the resistivity index of radial arteries (Spearman's correlation coefficient = -0.50, P = 0.0049). Grade 0 was more frequent in SSc patients than in controls (22.1% versus 3.3%; P < 0.05). In SSc patients, grade 0 was associated with severity markers of the digital vasculopathy such as digital ulcers (DUs) (current or past) (P < 0.05) or ulnar artery occlusion (P < 0.05). On the other hand, DUs were less frequent in patients with grade 4 (P < 0.05). A pathologic threshold of <2 (grade 0 or 1) was significantly associated with DUs (odds ratio 6.67 [95% confidence interval 2.31-19.21], P < 0.0001).

CONCLUSION

PDUS allowed a semiquantitative evaluation of FBPF in SSc patients and controls. Further studies are warranted to validate these results in independent SSc populations and to compare PDUS to existing tools assessing digital blood flow.