Best way to monitor perfusion of free flap:

 # Best way to monitor perfusion of free flap: 

A. Pulse oximeter 

B. Laser Doppler velocimetry 

C. Prick test 

D. Flourescin & dermoflourometer 

The correct answer is: C. Prick Test.

 During the postoperative phase, the flap is closely monitored for signs of compromised perfusion. Flaps are best assessed by inspection. Clinical monitoring is the current gold standard for assessing free flaps. Dermal bleeding or prick test is used to assess the colour of the blood within the flap circulation. Also scalpel mark on the flap can also be used to assess the colour of the blood.

Many high-end techniques are described in literature to monitor free flaps such as: 

• Serial fluorometry

• Plethysmography

• Laser doppler flow-metry

Reference: [Steel and Marran's head and neck surgery 4th ed 137]