No abstract

Peripheral nerve sensitivity (PNS) can be used as an indicator of nerve loss or damage known as peripheral neuropathy. Because peripheral neuropathy can result in morbidity and mortality, accurate monitoring of PNS is imperative.A review of the literature has shown that variables such as age, sex, compression force and temperature can effect PNS. Neither of the two clinical reference standards [Semmes‐Weinstein Monofilaments (SWM) or Bio‐Thesiometer (BT)] take these variables into account in determining PNS.We developed a novel instrument, VPT‐60, that measures PNS, temperature and compression force of a digit. It can vary the frequency of vibration and the rate of amplitude change among other variables.The correlation of these variables with PNS was analyzed in 41 subjects that exhibited a wide range of characteristics. We found a statistically significant correlation coefficient between VPT‐60 PNS and age [0.52 (p=0.001)]; sex [0.33 (p=0.03)]; finger weight [−0.045 (p=0.005)]; and finger temperature [0.34 (p=0.03)]. While the VPT‐60 had a significant correlation with both the SWM (0.75) and the BT (0.86), the BT correlation with SWM was only 0.51. At 60 Hz vibration, the VPT‐60 had a higher correlation with SWM than did the BT at 120 Hz.In this study, the VPT‐60 appeared to provide a better approach to determining peripheral nerve sensitivity and the factors that effect it than the SWM or BT.

There are approximately 13,000 fatalities resulting from alcohol‐impaired accidents each year. The use of accurate personal breath alcohol analyzers (BAA) could help reduce this number. The purpose of this study was to determine the accuracy of 5 consumer models of semi‐conductor type breath alcohol analyzers. For this study, each instrument was tested 10 times at three concentrations (0.035%, 0.070% and 0.087%) of a dry gas ethanol standard (National Institute of Standards‐traceable) at both room and human breath temperature. An evidentiary BAA (Lifeloc FC20) was also used as an internal control for the reference standard. The results of the study showed that none of the 5 instruments were accurate at any of the three concentrations tested. The accuracy was not affected by the change in temperature. Therefore, we concluded that none of the 5 breath alcohol analyzers studied could accurately inform the user of their breath alcohol status. Since these products are advertised as accurate, the advertisement appears to be misleading. Given the lack of accuracy found in this study, these breath alcohol analyzers would most likely not reduce the fatalities from alcohol‐impaired accidents.

The loss of peripheral nerve sensitivity can result in serious morbidity (including limb amputation) and mortality. Monitoring peripheral nerve sensitivity is important in avoiding these consequences.The purpose of this study was to evaluate the capability of an experimental VPT‐60 to accurately determine peripheral nerve sensitivity. Peripheral nerve sensitivity measurements from the VPT‐60 were compared to measurements of the two clinical reference standards, Semmes‐Weinstein monofilaments (SWM) and the Bio‐Thesiometer (BT).Peripheral nerve sensitivity and temperature of the index finger tip of 41 subjects, with ages ranging from 20–87 years, and mean SWM size range of 2.4–4.2 were measured. Finger tip temperature ranged from 71.4–88.2°F, and the force exerted by the finger on the vibrating probe ranged from <1.0 to 82 grams. Each subject's nerve sensitivity was measured 3 times with each of the 3 instruments.The correlation coefficient (r) of VPT‐60 and SWM was 0.75 and between the VPT‐60 and the BT was 0.86. The r between SWM and BT was only 0.51. As the nerve sensitivity decreased, the sensitivity of the VPT‐60 to detect changes increased. Reliability of the VPT‐60, SWM, and BT was 0.88, 0.78, and 0.74 respectively. In conclusion, this study indicates that the VPT‐60 provides results that are as capable as, if not more capable than, the gold standards in determining peripheral nerve sensitivity.