Anesthesia methods
hypotension, bleeding, obstruction of the catheter
QUINCKE, BLEEDING, BLOOD CLOT, SECONDARY, BLOOD, DECUBITUS
After the ultrasound examination, routine monitoring, including heart rate (HR), blood pressure, electrocardiogram, and peripheral oxygen saturation, was implemented, and baseline values were recorded. Blood samples were collected after inserting a peripheral venous catheter, and a rapid infusion of 6% hydroxyethyl starch (HES) 130/0.4 (Voluven®, Fresenius Kabi Japan, Tokyo, Japan) was started; a total of 1000 mL was administered during surgery. Subsequently, we placed the parturients in the lateral decubitus position and attempted CSEA. All parturients underwent epidural catheterization before spinal anesthesia. An 18-gauge Tuohy needle was introduced using loss of resistance to air to confirm the epidural space. A 19-gauge epidural catheter was inserted through the epidural needle, 3–4 cm into the Th12/L1 epidural space. Instead of an epidural test dose, we injected 2 mL saline through the epidural catheter to prevent obstruction of the catheter by a blood clot. During skin closure, the parturient received continuous epidural infusion of 0.2% ropivacaine for postoperative analgesia.All parturients received spinal anesthesia at the L3–4 interspace using a 25-gauge Quincke spinal needle (TOP Corp, Tokyo, Japan). Next, 0.5% hyperbaric bupivacaine (8 mg) mixed with fentanyl (20 µg) was administered intrathecally after free flow of cerebrospinal fluid was observed. According to the results of the pinprick tests, the surgeon commenced the operation once a sensory blockade above the T4 level was achieved. Vasopressors were administered when the systolic blood pressure was < 90 mmHg or decreased by > 20% of the baseline value. As a vasopressor, 1 mL phenylephrine (1 mg diluted to 10 mL [0.1 mg/mL] with normal saline) was administered for hypotension with HR ≥ 60 beats/min or 1 mL ephedrine (40 mg diluted to 8 mL [5 mg/mL] with normal saline) for hypotension with HR < 60 beats/min. We counted the administration of 0.1 mg of phenylephrine or 5 mg ephedrine as one dose.The primary outcome of this study was the total number of vasopressor boluses and dose of vasopressors among the three groups. The secondary outcomes were the CSA of the stomach antrum, maternal plasma glucose levels, serum sodium levels, total intravenous fluid, bleeding volume, urine volume, operative time, and cord blood gas values after delivery.