We will need to first determine the cause of your father's high blood pressure - whether it is anxiety or hypertension. In order to do that, you may want to bring your father to a medical general practitioner (GP) or cardiologist for a check up.
After your father's medical doctor has established the cause of the increase in blood pressure, do let your father's dentist/dental specialist know the following:
1) your father's existing medical conditions, if any
2) medications and the dosage taken currently, if any
3) name and contact number of your father's medical doctor.
As an oral surgeon practicing in a hospital-based dental group, we see alot of patients who have high blood pressure and/or heart conditions. When treating them, we work closely with their medical doctors/cardiologist before we proceed with any dental treatment to ensure that patient's well-being and safety is taken care of.
In the right hands and with appropriate measures in place, it is safe for patients with high blood pressure to undergo a dental extraction without the risk of excessive bleeding.
Best regards
Dr Ho Kok Sen