Finger blood flow measured in the exposed (right) middle finger of 10 healthy subjects before, during and after a 15 minute exposure to static load (contact force 10 N) and vibration with different combinations of frequencies (Hz) and unweighted acceleration magnitudes (m/s2 rms) but with the same frequency weighted acceleration (5.5 m/s2 rms) according to the frequency weighting of ISO 5349
Static load Vibration 16 Hz, 5.5 m/s2 Vibration 31.5 Hz, 11 m/s2 Vibration 63 Hz, 22 m/s2 Vibration 125 Hz, 44 m/s2 Vibration 250 Hz, 88 m/s2
Before exposure 24.3 (2.1) 25.5 (1.9) 23.4 (2.6) 25.1 (2.5) 24.1 (2.0) 26.7 (2.3)
Exposure (min):
E 0.5 18.5 (2.4) 17.9 (2.9) 9.7 (1.6) 11.0 (1.4) 11.0 (1.9) 12.6 (1.8)
−23.9% (−65.3% to 17.6%) −30.2% (−63.9% to 3.5%) −52.8% (−7.1% to −98.6%) −54.9% (−21.1% to −88.8%) −52.1% (−13.4% to −90.8%) −50.2% (−17.3% to −83.2%)
−6.7% (−48.2% to 34.7%) −24.4% (−58.1% to 9.3%) −54.1% (−8.4% to −99.9%) −51.4% (−17.6% to −85.7%) −49.0% (−10.3% to −87.7%) −48.4% (−15.4% to −81.4%)
E 3.5 23.2 (2.7) 17.3 (3.3) 9.6 (1.2) 9.8 (1.0) 9.2 (1.3) 11.6 (1.7)
−0.1% (−41.6% to 41.3%) −22.4% (−56.1% to 11.3%) −55.3% (−11.0% to −99.6%) −52.6% (−18.7% to −86.4%) −53.3% (−14.6% to −91.9%) −57.4% (−24.4% to −90.4%)
+6.0% (−35.4% to 47.5%) −30.5% (−64.2% to 3.2%) −56.4% (−13.0% to −97.8%) −52.3% (−18.5% to −86.1%) −51.8% (−13.1% to −90.5%) −49.8% (−16.8% to −82.8%)
E 15 27.0 (3.9) 15.2 (2.8) 10.5 (2.0) 11.5 (1.6) 8.6 (1.2) 11.5 (2.3)
+11.4% (−30.1% to 52.8%) −39.5% (−5.8% to −73.3%) −55.2% (−11.0% to −99.4%) −50.7% (−16.8% to −84.5%) −62.1% (−25.0% to −99.2%) −58.5% (−25.5% to −91.5%)
Recovery (min):
R 0.5 25.6 (3.0) 27.7 (3.9) 25.2 (2.8) 24.7 (2.3) 24.5 (2.6) 24.4 (2.1)
+7.8% (−33.6% to 49.3%) +7.8% (−25.9% to 41.5%) +17.3% (−28.5% to 63.0%) −0.1% (−34.0% to 33.8%) +3.5% (−35.2% to 42.1%) −7.3% (−40.3% to 25.7%)
+7.8% (−33.7% to 49.2%) +6.4% (−27.3% to 40.1) +21.9% (−23.9% to 67.6%) −2.7% (−36.6% to 31.1%) +17.2% (−21.5% to 55.9%) −8.3% (−41.3% to 24.7%)
+15.0% (−26.4% to 56.5%) −2.2% (−35.9% to 31.6%) +18.3% (−27.5% to 64.0%) −1.9% (−35.7% to 32.0%) +7.2% (−31.4% to 45.9%) −3.1% (−36.0% to 29.9%)
+19.2% (−22.3% to 60.6%) −0.3% (−33.9% to 33.4%) +16.1% (−29.7% to 61.8%) −6.8% (−40.6% to 27.0%) +18.3% (−20.3% to 57.0%) −4.6% (−37.6% to 28.4%)
+20.8% (−20.6% to 62.3%) −6.3% (−40.0% to 27.4%) +12.1% (−33.6% to 57.9%) +5.9% (−27.9% to 39.7%) −2.2% (−40.8% to 36.5%) −8.4% (−41.3% to 24.6%)
R 15 27.1 (2.6) 25.8 (2.4) 23.0 (2.0) 26.5 (2.5) 23.4 (1.8) 23.9 (1.9)
+13.3% (−28.1% to 54.8%) +1.6% (−32.1% to 35.4%) +14.4% (−31.3% to 60.1%) +12.6% (−21.3% to 46.4%) +3.4% (−35.2% to 42.1%) −5.8% (−38.8% to 27.2%)
R 22.5 22.9 (1.8) 25.4 (2.4) 21.4 (1.9) 21.0 (1.9) 20.1 (1.9) 19.3 (2.1)
−1.4% (−42.9% to 40.0%) −0.5% (−34.2% to 33.2%) +7.5% (−38.3% to 53.2%) −6.4% (−40.2% to 27.4%) −12.9% (−51.5% to 25.8%) −26.5% (−59.5% to 6.5%)
−6.4% (−47.9% to 35.0%) +9.2% (−24.5% to 42.9%) +2.3% (−43.5% to 48.0%) −19.7% (−53.5% to 14.1%) −35.1% (−73.8% to 3.6%) −44.9% (−77.9% to 11.9%)
+0.2% (−41.2% to 41.7%) +9.0% (−24.7% to 42.7%) −23.6% (−69.4% to 22.1%) −26.1% (−59.9% to 7.7%) −45.9% (−7.3% to −84.6%) −42.4% (−9.4% to −75.4%)
+15.3% (−26.2% to 56.7%) −4.8% (−38.5% to 28.9%) −20.9% (−66.6% to 24.9%) −24.7% (−58.6% to 9.1%) −44.4% (−5.7% to −83.0%) −47.0% (−14.0% to −80.0%)
ANCOVA (p value) 0.12 0.0005 <0.0001 <0.0001 <0.0001 <0.0001
Mean (SEM) values (ml/100 ml/min) and mean (95% CI) for the percentage changes in finger blood flow compared with the measures before exposure are also given.
p Values of repeated measures analysis of covariance (ANCOVA) are adjusted by age, finger volume, and room temperature.