2. Methods
hypoxemia
BLOOD, SECONDARY
This article adheres to the applicable CONSORT guidelines. The study is a prospective, randomized, and controlled trial performed in the Hospital of Hebei Medical University from June 2022 to January 2023. The protocol for the study was approved by the Institutional Ethics Committee of the Second Hospital of Hebei Medical University (2022-R278), and written informed consent was obtained from all subjects participating in the trial. The trial was registered prior to patient enrollment at the Chinese Clinical Trial Registry (The study included consenting patients aged 18 to 89 who underwent EBUS-TBNA and were classified by the American Society of Anesthesiologists (ASA) as II-III. Exclusion criteria included body mass index >28 kg/mA total of 187 patients were evaluated for eligibility, and 140 were enrolled following signing the informed permission form. Patients were randomly allocated to one of the two groups (randomly assigned 1 : 1): esketamine-propofol TCI group (group E, All patients fasted for 8 hours before EBUS-TBNA. In the operating room, patients took a supine position and received oxygen (4 L/min) via nasal cannula. Blood pressure, oxygen saturation (SpOIn group E, the initial propofol plasma target concentration was set at 1.4 The primary outcome was the dose and times of lidocaine given by the endoscopist. The endoscopist had the right to spray 1% lidocaine through the bronchoscope any time it was necessary according to the coughing response of patients. We set a limit of 2 ml per spray and a maximum dose of 7 mg/kg of lidocaine.The secondary outcomes were the incidence rate of hypoxemia (SpOOn the basis of the pre-experiment data, sample size was calculated. The dose of 1% lidocaine was 4.5 ml/h with an SD of 2.27 ml/h in group E and 5.77 ml/h with an SD of 2.83 ml/h in group P. Assuming a 5% dropout rate, 140 (70 per group) patients were needed with a power of 0.80 and a significance level of 0.05.In this study, statistical analyses were conducted using IBM SPSS Statistics software (Version 27.0, IBM Corp., Armonk, NY, USA). The Mann–Whitney 