What Causes Yellow Discoloration On The Face After Tooth Extraction?

My son is 16 and recently was diagnosed with congenital exercise-induced ventricular tachycardia. He took Metaprolol a few weeks but a Holter monitor test showed peak heart rates of 210 so he switched to Sectral (200mg twice per day), which he has taken about 10 days. This morning he had 4 wisdom teeth surgically removed. The first IV in his hand didn t work right and the medication went into the surrounding tissue. They then put an IV in his arm. I was away from him for a few hours, and when I returned I noticed his face looks yellow. I ve tried to talk myself out of the perception that his color has changed, but I can t, and my husband agrees. How quickly does this issue need to be addressed?