Nasopharyngeal Airway Facilitate Transnasal Humidified Rapid Insufflation Ventilatory Exchange

Inclusion Criteria: * Signed informed consent. * Undergoing surgery with general anaesthesia. * Adult, \>18 years old. * American Society of Anesthesiology classification I-II. Exclusion Criteria: * Coagulation disorders or a tendency of nose bleeding * An episode/exacerbation of congestive heart failure (CHF) that requires a change in medication, diet or hospitalization from any cause in the last 6 months * Severe aortic stenosis or mitral stenosis; * Cardiac surgery involving thoracotomy (e.g., coronary artery bypass graft (CABG), valve replacement surgery) in the last 6 months; * Acute myocardial infarction in the last 6 months; * Acute arrhythmia (including both tachycardia and bradycardia) with hemodynamic instability; * Diagnosed COPD or current other acute or chronic lung disease requiring supplemental chronic or intermittent oxygen therapy); * Increased intracranial pressure; * ASA \>II; * Mouth, nose, or throat infection; * Fever, defined as core body temperature \> 37.5°C; * Pregnancy, breastfeeding or positive pregnancy test; * Emergency procedure. * Patient with known or suspected difficult airway