Short answer: No. First of all, if you are poz but have an undetectable viral load, you don't need to worry that someone can become HIV-positive by coming in contact with your fluids: be they semen, saliva, or blood. New research shows that you cannot transmit the virus while undetectable. Regardless of whether you are undetectable or not, your surgery team still needs to know you're HIV-positive, and they will likely take additional precautions.
Second, although people living with HIV were once thought to be too sick or immune depressed to face the added risks associated with surgery, that hasn't been true in over a decade. A study published in 2006 in The Journal of the American Medical Association compared surgery data for both HIV-positive and HIV-negative patients and found that the two groups had the same level of complications from surgery. If you're trans and undergoing reassignment surgery, you may want to find a surgeon who can work with your HIV specialist.