Research methods
nausea, Stroke, stroke, vomiting, Postoperative Nausea and Vomiting, PONV, retching
STROKE, STROKE
The study was based on a randomized trial and the subjects were randomly classified into computer-generated numbers. Instructed nurses who did not know the study details randomly assigned the subjects by selecting high concentration and low concentration from a sealed envelope just before surgery. The allocation ratio was 1:1 for each group. After the patient arrived at the operating room, electrocardiogram, pulse oxygen saturationAdministration of remifentanil during anesthesia maintenance was performed by a target-controlled infusion (TCI) device with an effective site concentration of 8 ng/ml in the high-concentration group and of 4 ng/ml in the low-concentration group. The TCI device was prepared in advance by an instructed nurse, and the fixed concentration of drug was sealed. The anesthesiologist who administered the anesthesia was, therefore, blinded to the concentration of remifentanil used. The effect-site concentration of propofol was adjusted by 0.2 µg/ml from the initial concentration to maintain a BIS value of 40–60. Ephedrine was used 5-10 mg intravenously only when MAP falls below 60 mm Hg.At the end of the operation, propofol and remifentanil were discontinued; pyridostigmine 0.2 mg/kg and glycopyrrolate 0.008 mg/kg were injected intravenously to reverse the muscle relaxant effects; and extubation was performed under the influence of a nerve stimulator.Baseline systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), heart rate (HR), BIS, stroke volume (SV), and cardiac output (CO) levels were measured immediately after arrival at the operating room. The variables also were measured immediately after endotracheal intubation and at 30, 60, and 90 min after the start of surgery, for observation and comparison. Stroke volume and cardiac output were measured using non-invasive cardiac monitoring, for which the CSN-1901 (Nihon Kohden, Tokyo, Japan) was used. Evaluation of the surgical condition was conducted by a single operator using the Boezaart surgical field grading scale (Table Surgical grading scoring system designed specifically for use in endoscopic sinus surgeryThe total doses of propofol and remifentanil administered during anesthesia were recorded.After 30 min and within 24 h of recovery room arrival, the Visual Analog Scale (VAS) and Postoperative Nausea and Vomiting (PONV) score were measured. The PONV score was divided into 4 categories, 0 = none, 1 = nausea, 2 = retching, and 3 = vomiting. Ramosetron was given to the patients who experienced PONV.