Finger blood pressure and rewarming rate for screening and diagnosis of Raynaud's phenomenon in workers exposed to vibration

Effect of room temperature on tests for diagnosing vibration-induced white finger: finger rewarming times and finger systolic blood pressures

PURPOSE

This study investigates the effects of room temperature on two standard tests used to assist the diagnosis of vibration-induced white finger (VWF): finger rewarming times and finger systolic blood pressures.

METHODS

Twelve healthy males and twelve healthy females participated in four sessions to obtain either finger skin temperatures (FSTs) during cooling and rewarming of the hand or finger systolic blood pressures (FSBPs) after local cooling of the fingers to 15 and 10 °C. The measures were obtained with the room temperature at either 20 or 28 °C.

RESULTS

There were lower baseline finger skin temperatures, longer finger rewarming times, and lower finger systolic blood pressures with the room temperature at 20 than 28 °C. However, percentage reductions in FSBP at 15 and 10 °C relative to 30 °C (i.e. %FSBP) did not differ between the two room temperatures. Females had lower baseline FSTs, longer rewarming times, and lower FSBPs than males, but %FSBPs were similar in males and females.

CONCLUSIONS

Finger rewarming times after cold provocation are heavily influenced by room temperature and gender. For evaluating peripheral circulatory function using finger rewarming times, the room temperature must be strictly controlled, and a different diagnostic criterion is required for females. The calculation of percentage changes in finger systolic blood pressure at 15 and 10 °C relative to 30 °C reduces effects of both room temperature and gender, and the test may be used in conditions where the ±1 °C tolerance on room temperature required by the current standard cannot be achieved.

Assessment of two alternative standardised tests for the vascular component of the hand-arm vibration syndrome (HAVS)

Background

Vibration-induced white finger (VWF) is the vascular component of the hand–arm vibration syndrome (HAVS). Two tests have been standardised so as to assist the diagnosis of VWF: the measurement of finger rewarming times and the measurement of finger systolic blood pressures (FSBPs).

Objectives

This study investigates whether the two tests distinguish between fingers with and without symptoms of whiteness and compares individual results between the two test methods.

Methods

In 60 men reporting symptoms of the HAVS, the times for their fingers to rewarm by 4°C (after immersion in 15°C water for 5 min) and FSBPs at 30°C, 15°C and 10°C were measured on the same day.

Results

There were significant increases in finger rewarming times and significant reductions in FSBPs at both 15°C and 10°C in fingers reported to suffer blanching. The FSBPs had sensitivities and specificities >90%, whereas the finger rewarming test had a sensitivity of 77% and a specificity of 79%. Fingers having longer rewarming times had lower FSBPs at both temperatures.

Conclusions

The findings suggest that, when the test conditions are controlled according to the relevant standard, finger rewarming times and FSBPs can provide useful information for the diagnosis of VWF, although FSBPs are more sensitive and more specific.

International consensus criteria for the diagnosis of Raynaud's phenomenon

Vasoconstriction accompanied by changes in skin color is a normal physiologic response to cold. The distinction between this normal physiology and Raynaud's phenomenon (RP) has yet to be well characterized. In anticipation of the 9th International Congress on Autoimmunity, a panel of 12 RP experts from 9 different institutes and four different countries were assembled for a Delphi exercise to establish new diagnostic criteria for RP. Relevant investigators with highly cited manuscripts in Raynaud's-related research were identified using the Web of Science and invited to participate. Surveys at each stage were administered to participants via the on-line SurveyMonkey software tool. The participants evaluated the level of appropriateness of statements using a scale of 1 (extremely inappropriate) through 9 (extremely appropriate). In the second stage, panel participants were asked to rank rewritten items from the first round that were scored as "uncertain" for the diagnosis of RP, items with significant disagreement (Disagreement Index > 1), and new items suggested by the panel. Results were analyzed using the Interpercentile Range Adjusted for Symmetry (IPRAS) method. A 3-Step Approach to diagnose RP was then developed using items the panelists "agreed" were "appropriate" diagnostic criteria. In the final stage, the panel was presented with the newly developed diagnostic criteria and asked to rate them against previous models. Following the first two iterations of the Delphi exercise, the panel of 12 experts agreed that 36 of the items were "appropriate", 12 items had "uncertain" appropriateness, and 13 items were "inappropriate" to use in the diagnostic criteria of RP. Using an expert committee, we developed a 3-Step Approach for the diagnosis of RP and 5 additional criteria for the diagnosis of primary RP. The committee came to an agreement that the proposed criteria were "appropriate and accurate" for use by physicians to diagnose patients with RP.

Diagnostic performance of cold provocation test with hands immersion in water at 10°C for 5 min evaluated in vibration-induced white finger patients and matched controls

PURPOSE

This study aimed to explore the diagnostic ability of the cold provocation test with hands immersion in water at 10°C for 5 min in diagnosing vibration-induced white finger (VWF).

METHODS

Finger skin temperature (FST) was measured in 20 VWF patients and 20 matched healthy controls, at palmar side of the distal phalanges of fingers from both hands before, during, and after hands immersion in water at 10°C (for 5 min with waterproof coverings put on both hands). Data from 4 fingers (except thumb) were evaluated at five time points: just before immersion, last minute during immersion, and at 5th, 10th, and 15th min during the post-immersion or recovery period.

RESULTS

A positive group difference between patients and controls was revealed during the recovery period. During recovery at 95 and 70% specificity, the sensitivity ranged from 20 to 30% and 50 to 70% for evaluation with average FST for 4 fingers and 15-35% and 60-65% for evaluation with minimum FST among 4 fingers, respectively. Overall, evaluation of absolute FST at 15th min of recovery offered better diagnostic ability.

CONCLUSIONS

The cold provocation test with hands immersion in water at 10°C for 5 min could discriminate VWF patients from healthy controls; however, this test has a limited diagnostic value in diagnosing patients with VWF.

Diagnosis of vascular injuries caused by hand-transmitted vibration

OBJECTIVE

For a reliable objective diagnosis of vascular injuries in hand-arm vibration syndrome (HAVS), the standardized cold provocation tests--finger skin temperature measurement during hand(s) immersion in cold water (FST test) and finger systolic blood pressure measurement during local cold exposure (FSBP test)--are widely used. In recent years there is a growing controversy regarding the diagnostic value of these tests. The aim of this study was to describe particularly the diagnostic performance of FST and FSBP tests, and also to focus on the problems and uncertainties regarding the test conditions and results, in the laboratory diagnosis of vascular injuries caused by hand-transmitted vibration.

METHOD

A review of pertinent published English- and Japanese-language articles and conference proceedings (between 1976 and 2006) was conducted.

RESULTS

From the reports with regard to diagnostic significance of the FSBP test, it seems to be an important laboratory test for diagnosing vibration-induced white finger (VWF). On the other hand, despite a large number of research studies with the FST test, there is a lack of data for the standardized FST test, which can confirm the value of it in diagnosing VWF. Moreover, there is no agreement on effective parameter/s to quantify and compare the responses in FST induced by immersion in cold water. While assessing and staging vascular injuries in HAVS, inquiry regarding finger coldness appears to be useful.

CONCLUSIONS

As there is no single test with satisfactory diagnostic ability for VWF, at present it is reasonable to use the cold provocation tests as a part of the comprehensive approach to evaluate HAVS patients. In addition to the objective methods, the index of finger coldness may be useful while diagnosing the vascular component of HAVS.

Laser Doppler imaging of skin blood flow for assessing peripheral vascular impairment in hand-arm vibration syndrome

The objective of this study was to evaluate the usefulness of laser Doppler imaging (LDPI) of the skin blood flow for assessing peripheral vascular impairment in the hand-arm vibration syndrome (HAVS). The subjects were 46 male patients with HAVS, aged 50 to 69 yr, and 31 healthy male volunteers of similar age as controls. A cold provocation test was carried out by immersing a subject's hand on his more severely affected side into cold water at a temperature of 10 degrees C for 10 min. Repeated image scanning of skin blood flow of the index, middle, and ring fingers was performed every 2 min before, during, and after the cold water immersion using a PMI-II laser Doppler perfusion imager. The mean blood perfusion values in the distal phalanx area of the fingers were calculated on each image. The patients suffering from vibration-induced white finger (VWF, n=20) demonstrated significantly lower skin blood perfusion at each interval of the test as compared with those without VWF (n=26) and the controls (p<0.01, ANOVA). The blood perfusions in the HAVS patients were associated with the severity of the symptoms as classified by the Stockholm Workshop scale for vascular staging. When a subject was considered to be positive if any of the tested fingers showing a decreased blood perfusion and/or a delayed recovery pattern, the sensitivity was 80.0%, and the specificity was 84.6% and 93.5% for patients without VWF and the controls, respectively. These results suggest that the LDPI technique could provide detailed and accurate information that may help detect the existence of impaired vascular regulation to cold exposure in the fingers of workers exposed to hand-transmitted vibration.

Test battery for assessing vascular disturbances of fingers

The diagnosis of vibration-induced white finger (VWF) is difficult, often relying on medical interview and history. The condition is characterized by an exaggerated vasoconstriction of digital arteries in response to cold. The complete closure of digital arteries is episodic and results in a characteristic blanching that is rarely observed by a clinician. Objective measurements of the response of the digital circulation to cold can assist in evaluating a patient for VWF. Finger systolic blood pressure (FSBP) following local cooling is a measure of cold-induced vasoconstriction in digital arteries and is an assessment of vasomotor tone. Low FSBPs following cooling are indicative of dysfunction. Finger skin temperature (FST) following hand cooling is a measure of cutaneous blood flow. The mechanism underlying the recovery of cutaneous blood flow following cooling is as yet not fully understood, but a delayed recovery is believed to arise from persistent vascular disturbances of the fingers or from a resulting in conflicting opinions concerning the utility of the measurements, a scarcity of comparable data from epidemiological investigations, and limited normative data to aid clinicians in decision-making. This review of evidence on which the tests are based is aimed at providing clinicians and researchers with an understanding of the factors that must be considered when conducting the tests, interpreting the results, and comparing results between different studies.

Different conditions of cold water immersion test for diagnosing hand-arm vibration syndrome

The cold water immersion test with finger skin temperature (FST) measurement is used to assess vascular disorders in hand-arm vibration syndrome (HAVS). The test method is currently being standardized within the International Organization for Standardization (ISO) in which a water temperature of 12°C for 5 min of hand immersion and an option of using a waterproof hand covering during immersion are proposed. It is necessary to evaluate the diagnostic significance of the test with FST measurement under different conditions to provide a proper management of HAVS patients. The aim of this article is to review research findings of this test with FST measurement and discuss test conditions influencing the results and diagnostic significance.Different conditions were employed, and the test results were shown to be influenced by water temperature, immersion time and other conditions such as room temperature, season, ischemia during immersion, and evaluation parameters. These factors need to be considered in the standardization of the cold water immersion test with FST measurement. It has been mentioned that a high water temperature, a short immersion time and other conditions should be chosen to expose a subject to minimal suffering during the test. A water temperature between 10°C and 15°C and a 5 min immersion might be suitable for the cold water immersion test. The reported sensitivity and specificity evaluating rewarming to the initial temperature for the test using a water temperature of 12°C and a 3 min immersion are 58% and 100%, respectively; these are low but similar to those for tlie water immersion test at 10°C. Therefore, the proposed cold water immersion test at 12°C for 5 min by the ISO (Draft International Standard) is the focus of much interest, and further studies are needed to obtain sufficient data for evaluating the diagnostic significance of the test. At present, the test needs to be used together with a test battery.

Factors influencing finger systolic blood pressure test for diagnosis of vibration-induced white finger

Finger systolic blood pressure (FSBP) measurement during finger cooling is a feasible method for the diagnosis of vibration-induced white finger (VWF). The standardization of the FSBP test is required. The final draft of an international standard for the measurement and evaluation of FSBP (ISO/DIS 14835-2) has been proposed in 2004. The aim of this review is to overview factors influencing the FSBP test and discuss some issues in the final draft. The FSBP test is a method of diagnosing VWF with reasonable sensitivity and specificity, although the sensitivity was relatively low in studies of mild VWF. The test results depend on cold provocation procedures including finger cooling, body cooling, room temperature and other factors such clothing and smoking. There are some versions of procedures for cold provocation and the tested fingers in the final draft. These may cause a low sensitivity of the FSBP test. To determine how the methodological difference influence the results of the FSBP test, further studies are needed. Although there are issues in the draft, the international standard of the FSBP test is extremely useful for the diagnosis, treatment and compensation of VWF.

Skin temperature recovery from cold provocation in workers exposed to vibration: a longitudinal study

BACKGROUND

Vibration white finger (VWF) is characterised by arterial hyperresponsiveness and vasoconstriction following cold provocation. Several years after of removal from exposure, most subjects show improved finger systolic blood pressure (FSBP) under conditions of cold challenge, but continue to report cold hands and finger blanching.

AIMS

To assess the underlying reasons for the persistence of cold symptoms.

METHODS

A total of 204 former users of pneumatic tools with cold related hand symptoms were evaluated and then re-evaluated a year later. Symptoms were evaluated using the Stockholm Workshop Scale. Finger systolic blood pressure per cent (FSBP%) was assessed by comparing digital blood pressure in a cold provoked and normalised state. Fingertip skin temperature was measured during cooling and occlusion and during rewarming and recovery.

RESULTS

There were dramatic improvements in FSBP% (14.3 mm Hg %), modest improvement in recovered skin temperature (0.86 degrees C), and no change in symptom stage. When the most symptomatic subjects (n = 75) were compared with the less symptomatic subjects (n = 129), there were similar inter-test improvements in FSBP%. Skin temperature recovery improved in the less symptomatic (+1.49 degrees C), but did not change in the most symptomatic group (-0.12 degrees C). However, the more symptomatic group had higher temperatures at the initial test, thus qualifying the result.

CONCLUSIONS

Skin temperature recovery after cold challenge in subjects with VWF remains reduced in the symptomatic subjects several years after exposure removal. This is evident even when blood pressure has increased in the setting of cold provocation. Results suggest that in VWF, the dermal circulation remains impaired, even after the restoration of arterial blood pressure in the digits.