Qom University of Medical Sciences Journal

Background and objective
Intraoperative bleeding, which reduces visibility in the operative field, is one of the major
problems of head and neck surgeries. Improvement of intraoperative visibility and reduction
of bleeding is an important task for an anesthetist during head and neck surgery. It has been
shown that preoperative beta-blockade decreases bleeding during the operation.
Methods
In a 18 month period,88 patients , who were candidate for nasal procedures in hazrat Rasul
medical complex, were selected in a randomized open clinical trial study. They were divided
to 4 groupes:
50 mg metoprolol at night before surgery
50 mg metoprolol in the morning of the surgery
50 mg metoprolol at night before surgery and in the morning of the surgery
placebo
Heart rate, Systolic and diastolic blood pressure was measured in a non-invasive way just
both upon arrival on the operation bed and after induction of anesthesia during operation. For
evaluation of the visibility of the operative field during operation the quality scale proposed
by Fromm and Boezzart was used.
Results
SPSS13 was used for assessment. There was significant relationship between metoprolol
administration and bleeding during the operation. All patients who received two doses of
metoprolol one in the last night and another in the morning of the operation day had only mild
bleeding. There was statistically significant relation between agitation and time of
administration of metoprolol.
Conclution
Nowadays, there are growing evidences that not only decrease in systolic blood pressure but
also a low heart rate (< 60 beats per minute) can minimize surgical bleeding. Both of the
above mentioned effects could be induced by beta blockers.
In this study, two doses of metoprolol could decrease the amount of bleeding and improve the
operation field significantly and also could decrease the agitation in recovery room.