No change in O2 saturation but measurable difference in thenar flexor power after radial artery harvest.

Abstract

Objective measures of morbidity will be required to establish the radial artery (RA) as a viable long term alternative to saphenous vein. The RA is the dominant arterial supply to the thenar musculature. We hypothesised that RA harvest should decrease O2 saturation and thenar muscle power. RA was harvested from non-dominant (ND) limbs only (left n = 58, right n = 21). Oximeter values of O2 saturation were taken from the thumb of the dominant (D) and non-dominant (ND) limb pre and post operatively. A syringe filled with 25 cc of air is emptied against a one way valve connected to a pressure generator MX 100 by MEDEX, Inc, Ohio, USA. Three measures of thenar flexor power (TFP) were taken and mean values obtained in the ND and D limbs. O2 saturation ranged from 92 to 98% in the thumb of the ND limbs 24 h post RA harvest. The values for TFP (mean +/- SD) were 1246 +/- 246 mmHg (ND) and 1240 +/- 258 mmHg (D) pre-operatively and 1216 +/- 250 (ND) and 1259 +/- 233 (D) post operatively. The changes in TFP between the ND and D limbs (37.0 +/- 60.6 ND and 1.86 +/- 65.9 D) were significant for the D against the ND limb (P < 0.001). This reduction in TFP for the harvested limb was also found when considering handedness (28.0 +/- 24.2 and 40.3 +/- 69.2 for the left and right handed patients respectively). Our findings confirm the hypothesis that there are objective differences in TFP pre and post RA harvest at 3 months. Further studies are required to assess the clinical significance and persistence of the loss of TFP.