100% Fainting with needles/blood, what does a dr do if an IV is needed?

Male 29 years old 5’4 106 pounds / lbs

no medicines

never a smoker

no diagnosed medical conditions

Very lean

Possible OCD/Agoraphobia with no official diagnosis, scared of throwing up

100% fainting with small seizure like actively upon fainting with blood draws or needles or blood in general

Agoraphobic and has not had blood work done in years. Recently had bradycardia more pronounced during sleep (only diagnostic tool is an Apple Watch) heart rates between 35-40 both asleep and conscious with the ability to increase heart rate with activity

Extreme fatigue, but has a very physically demanding job for 12 hours, 4 days a week

Struggles to eat due to fear of throwing up

Suspected hypothyroidism (pending blood test results now)

My question is, if there were ever a need for an IV, what would a doctor do in this situation if fainting would be a guarantee over and over if an IV is in the arm?