Objective: Evaluation of effect of intrathecal co-administration of dexmedetomidine and bupivacaine on spinal anesthesia blocks characteristics in patient undergoing elective caesarean section . Setting : In this prospective randomized double blind clinical trail 50 patients who will scheduled for cesarean section under spinal anesthesia in besat hospital of sanandaj will be randomly divided in to 2 equal 25 patient group .
Inclusion criteria: writing consent form, American Society of Anesthesiologist physical status 1 or 2. Exclusion criteria: preeclampsia or eclampsia, diabetes mellitus, chronic hypertension, cardiovascular disease, renal disease, hepatic failure, and known allergy to study drugs.
Method: After insertion of two G20 venous catheters in dorsum of patient’s hands 10 Ml/Kg normal saline will be infused to patients. Standard monitoring will be start for patient and basic values will be record. Spinal anesthesia will be done in sitting position via L3-L4 or L4-L5 space using disposable (G=26) needle. Following spinal anesthesia patient immediately turned to supine position and about 5 degree head down.
Intervention: induction of spinal anesthesia will be done by using 12.5 mg bupivacaine plus 5 mic dexmedetomidine in study group, and the same value of bupivacaine plus 0.5 ml 0.9% normal saline in control group (volume of drug will be reached to 3 ml by adding stilled water in both group). Primary outcome: peak of sensory block and the needing time to reach that, the needing time to reach motor block to highest degree of modified bromage scale, time of regression of sensory block to level of S1 and regression of motor block to modified bromage scale 1. Secondary outcome: cardiovascular change during first 30 min of anesthesia, and complication of block.
Blinding: patient, anesthesiologist who do spinal anesthesia, and the anesthesiologist who evaluate study outcomes are unaware about patients grouping .