Controlled hypotension has been used as a mean of reducing intraoperative blood loss and better visualization of the surgical field in nasal surgeries. Perfusion index has been considered a useful tool for monitoring changes in peripheral perfusion using Masimo set and serum lactate for central perfusion. Many medications were used to induce hypotension. In this study we will compare the effects of tridil and labetalol on the perfusion.

The purpose of this study to detect the degree of hypotension that helps the surgeon and dosen't impair patient's perfusion and to compare the hypotensive effects of both tridil and labetalol infusions on the perfusion.

Inclusion Criteria:

• ASA I-II males and females aged 18-45 years who were scheduled for Functional Endoscopic sinus surgery (FESS)

Exclusion Criteria:

• uncontrolled hypertension, cerebrovascular disorders, bleeding and coagulation disorders, coronary artery diseases, renal or hepatic diseases or known hypersensitivity to the drugs used and pregnant.