Study design
sore throat, glottis, SARS-CoV-2 infection, upper respiratory tract infection
SORE THROAT, UPPER RESPIRATORY TRACT INFECTIONS, SARS-COV-2 INFECTION, BEST
A randomized controlled trial was conducted in the First Affiliated Hospital of the University of Science and Technology of China (USTC). The study was approved by the ethics committee of the First Affiliated Hospital of USTC (approval no. KY2022-337). This trial was registered in the Chinese Registry of Clinical Trials (We enrolled patients who were aged 18–75 years, had ASA physical status I-III, had SARS-CoV-2 infection 3 months prior to surgery, and had received elective thoracoscopic lung surgery using DLTs from December 2022 to April 2023. The following patients were excluded: (1) those who refused to participate; (2) those with a recent incidence of sore throat or upper respiratory tract infection orhoarseness; (3) those with a Mallampati score of 4; and (4) those with a history of difficult airway.Each individual was randomly assigned to the thermal softening group or the control group in a 1:1 ratio on the basis of a random table generated by a computer randomization program. The random sequence was placed in opaque, sealed envelopes. Patients, anesthesiologists, surgical team members, nurses, and postoperative follow-up evaluators were blinded to group assignment. After patients entered the operating room, the envelope was opened by a researcher who was also blinded to group allocation. The researcher prepared and pretreated all DLTs(Tuoren Best Medical Equipment Company, Henan, China). The size of the DLT depended on the patients’ gender and height [
The thermal softening process for the DLT. Once the patient entered the operating room, blood oxygen saturation, electrocardiography, heart rate, noninvasive blood pressure, and bispectral index (BIS) were continuously monitored. Invasive arterial blood pressure was monitored by radial artery puncture and catheterization after local anesthesia.Anesthesia was induced using midazolam (0.05 mg/kg), etomidate (0.3 mg/kg), sufentanil (0.5 µg/kg), and cisatracurium (0.2 mg/kg). An otorhinolaryngologist blinded to group allocation evaluated the vocal cords of the patients before tracheal intubation by using a video laryngoscope and acquired photographs for subsequent comparison. Tracheal intubation was performed by an anesthesiologist with experience in performing over 500 DLT insertions by using a video laryngoscope (INSIDES Medical Technology Company, Shenzhen, China). Endotracheal intubation was performed with a disposable polyvinyl chloride DLT by using a video laryngoscope. After inserting the tip of the bronchus forward through the glottis, the anesthesiologist removed the tube core and continue pushing forward.If substantial airway resistance was encountered, the anesthesiologist rotated the DLT counterclockwise or clockwise by 90° and then pushed it forward. If severe resistance was still experienced, the anesthesiologist again rotated the DLT counterclockwise or clockwise by 90° and subsequently advanced the DLT [Thirty minutes before the completion of the surgery, the patients were intravenously administered 1 mg kg