ABSTRACT
It has been suggested that direct monitoring of arterial temperature using implanted
thermocouples, may have value as a clinical postoperative monitor for vascularized
free tissue transfers, including those with no visible surfaces. This study evaluated
the technique in experimental animals, using simple, inexpensive equipment.
Mean arterial differential temperature changes, with ipsilateral (n = 20) and contralateral
(n = 21) references, of 0.6°C and 0.5°C respectively, reliably indicated occlusion
of the superficial femoral artery in situ. In epigastric island flaps, arterial occlusion (n = 24) produced mean arterial temperature
changes of 0.5°C, but changes after venous occlusion were not significantly greater
than unoccluded base line fluctuation. Venous differential temperature did not change
significantly after either arterial or venous occlusion.
In six epigastric free flaps, success or failure could not be distinguished, as the
wide variation in measurements in the four successful flaps overlapped the recordings
in the two which failed.
It was shown that the nearer to the body core, the less the temperature difference
between arterial wall and periarterial tissue. Occlusion of deeply sited arteries
produced little or no change in arterial temperature.
In view of these findings and because of the invasive nature of the technique, the
authors did not pursue it clinically.
