Skin Flap Circulation: Simultaneous Monitoring with Laser Doppler and Electromagnetic Flowmeters in the Pig Island Buttock Flap

Abstract

Twenty-two island skin flaps based on the deep circumflex iliac vessels were elevated in pigs. A comparative study of Laser Doppler flowmetry (LDF) and electromagnetic flowmetry (EMF) was undertaken. Flow values were compared during selective arterial and venous occlusion. nerve stimulation and intra-arterial noradrenaline or papaverine injection. The effectiveness of flap temperatures and blood gas data in monitoring vascular occlusions was also investigated. Similar and simultaneous responses in LDF and EMF values were noted during the different experimental manipulations, but for single simultaneous LDF/EMF observations from different animals the correlation coefficients were poor. The accuracy of EMF measurements in monitoring total flap inflow was confirmed by a high correlation with total venous outflow values. Major vascular occlusions also resulted in significant changes in the flap temperatures, and in the flap blood gases.

Key Words:

• Laser Doppler flowmetry
• electromagnetic flowmetry
• skin flap
• skin temperature
• blood gas tension
• oxygen consumption.