Study procedure and monitoring
pain
QUINCKE, -20
Patients were given 30-50 µg/kg midazolam as a sedative before surgery, and all patients received 5 ml/kg normal saline (NS) before intrathecal injection for 15-20 minutes. During surgery, the flow rate was sustained at 4 L/min via a simple oxygen mask. Spinal anesthesia was administered for the patient in a sitting position in the L2–3 vertebral interspace. A 25-gauge Quincke spinal needle was introduced into the dura mater. Patients were randomly divided into two groups by block randomization technique with a 1:1 allocation ratio, a block size of 4. Next, group A (n=27) patients received 2 ml 0.5% bupivacaine (10mg) + 0.5ml of normal saline, and group B (n=27) patients received 2 ml 0.5% bupivacaine (10 mg) + 0.5 ml of fentanyl (25 µg) administered at a rate of 0.1 mL/sec. The injections were carried out ensuring the spinal needle's orifice faced the cephalad and confirming the unimpeded flow of cerebrospinal fluid (CSF). All patients were placed in the supine position immediately after SA and in the lithotomy position.Patients were provided with 1 mg of midazolam for sedation if necessary during the procedure, sufficient to ensure they could respond to questions. Also, intravenous bolus fentanyl (25µg) was prescribed if analgesia was needed. The patient's blood pressure (BP) was monitored and recorded every 2 to 10 minutes immediately after intrathecal injection and then every 5 minutes until the end of surgery by a non-invasive blood pressure (NIBP) sphygmomanometer. BP was repeatedly measured and recorded inside the recovery ward. In case of moderate arterial hypertension (MAP) below 90 mmHg or less than 80% baseline, 5 mg intravenous ephedrine bolus was repeated, and atropine (0.5 mg) was used for a heart rate of less than 50 beats per minute. Patients in both groups were monitored with continuous electrocardiography (ECG), peripheral oxygen saturation (SpO2), heart rate (HR), and respiratory rate (RR), which were also recorded every five minutes during surgery, at the time of recovery, and admission to the ward.Sensory block level (SBL) was evaluated in patients with no sense of pain following the pinprick test every minute until reaching the highest level of sensory block. Additionally, the Modified Bromage Scale [