Randomization and blinding
death, congenital malformations, disability
EVENT, ADVERSE EVENT
Patients were randomly divided into a capnography group or a standard group in a 1:1 ratio using a random sequence of numbers generated through computerized randomization software. In the capnography group, the capnographic data of the patients were available for additional noninvasive assessment of ventilation. The capnographic data of patients assigned to the standard monitoring group were not visible because the carbon dioxide sampling port of the nasal cannula was kept closed; therefore, only the integrated pulse oximetric readout of the monitor was visible.Investigators randomly assigned patients to the study groups by opening pre-generated, sequentially numbered, opaque, sealed envelopes. The patients, endoscopy unit staff, and endoscopists were blinded to the study arm assignments. Both groups used nasal cannulae with carbon dioxide collection devices in identical packaging and shapes that were connected to capnography devices. A subject could be unblinded in the event of a severe adverse event requiring hospitalization or prolonged hospitalization (disability, affecting the ability to work; life-threatening or death; causing congenital malformations) or another emergency. The sponsor, study director, and clinical monitor were notified before unblinding.