Study comparing headache rates after two different spinal anaesthsia approaches for caeserian section procedure

Two hundred pregnant, gestational age 38-40, between the ages of 19-45 yr, ASA physical status I, scheduled to undergo elective caesarean section under spinal anesthesia, will study. All patients were expected to fast 6-8 hours before CS, and no one will premedicate. Routine monitors (consisting of a pulse oximeter, 3-lead ECG and a non-invasive blood pressure cuff) will apply. Baseline measurements will obtaine while patients were supin position. Following prehydration with Ringer’s lactate solution 10 ml/kg, spinal anesthesia will induce with hyperbaric bupivacaine 10-12.5 mg via a 25 G Quincke-tip spinal needle in the sitting position at the L4-5 vertebral level using a median (Group M) or paramedian (Group PM) approach by an anesthesiologist with more then 8 years experience (MSU). The patients will randomize, by using a computer-generated block randomisation, into 2 groups: Group M (n=100) median approach, Group PM (n=100) paramedian approach. Patients will then positione in a 10 degrees left-lateral tilt. Oxygen (4 l.min-1) will administere through a facemask. Surgery will initiate when the sensory block level reached at T4. Systolic (SBP), diastolic (DBP),mean (MBP) blood pressure, heart rate (HR), oxygen saturation (SpO2) values will continuously record (basal, after spinal anesthesia, at the start of surgery, every 5 minutes during surgery, at the end of surgery). Hypotension will define as a decrease in SBP of higher than 30 percent below baseline or to less than 90 mmHg and will treate by increasing the rate of crystalloid infusion. If hypotension persiste a bolus of iv ephedrine 5 mg will given. Bradycardia will define as HR less than 60 beats/min and was treated with iv atropine 0.5 mg. Patiens demografic data (age, weight, height, gestation, gravidity), duration of surgery, number of hypotensive episodes, total ephedrine and fluid requirements, intraoperative nausea and vomiting and shivering will also note. The patients will questione for possible occurrence of spinal anesthesia induced headache on the first, third and seventh postoperative days. A telephone followup call will use if the hospital stay is shorter than 7 days. Post dural puncture headache evaluations will performe by a different anesthesiologist blinded to the study.