Transnasal Microstream EtCO2 Reduces Hypoxemia During Emergence in Aged Post-Abdomen Surgery

ConditionsElderly Patients Laparoscopic Surgery Postoperative Hypoxemia Capnography

Trial statusNot yet recruiting

Trial phaseNot applicable

Trial typeInterventional

Biological sexAll

Age65-80

SponsorJianbo Wu

About this trial

This prospective, randomized controlled study aims to investigate whether transnasal microstream end-tidal carbon dioxide (EtCO₂) monitoring in the post-anesthesia care unit (PACU) reduces the incidence of postoperative hypoxemia in elderly patients (65-80 years, ASA I-III, BMI 18-30 kg/m²) undergoing elective laparoscopic surgery under general anesthesia with endotracheal intubation. A total of 324 patients will be randomized 1:1 to either the control group (standard SpO₂ monitoring and clinical observation with oxygen delivery at 2 L/min via sampling line) or the experimental group (same oxygen delivery plus continuous real-time transnasal microstream EtCO₂ monitoring). The primary outcome is the incidence of hypoxemia (SpO₂ \< 90% for \>15 seconds) after extubation in the PACU. Secondary outcomes include severe hypoxemia (SpO₂ \< 85%), lowest SpO₂ during PACU stay, vital signs at specified time points, PACU length of stay, and other adverse events. Statistical analysis will use chi-square or Fisher's exact test for the primary outcome, with a sample size calculated to detect a reduction in hypoxemia from 33% (control) to 18% (experimental group) (α=0.05, power=80%, plus 20% dropout).

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

Age 65-80 years;

ASA physical status I-III;

BMI 18-30 kg/m²;

Participants scheduled for elective laparoscopic surgery under general anesthesia with endotracheal intubation;

Disqualifiers

Patients with nasal bleeding, nasal mucosal injury, nasal cavity occupancy, or other conditions that preclude transnasal carbon dioxide monitoring;

Patients undergoing emergency surgery;

Participants requiring postoperative assisted ventilation via endotracheal intubation or tracheostomy;

Presence of any disease or condition that may cause abnormal end-tidal carbon dioxide waveforms or abnormal baseline pulse oximetry (e.g., congenital heart disease or chronic lung disease);

Trial design

Design model

Parallel

Treatments tested in this trial

EtCO₂ Monitoring
Device
After extubation, the sampling line is placed between the patient's mouth and nose to deliver oxygen at 2 L/min. The sampling line is connected to a patient monitor (RespArrayTM) to initiate continuous real-time transnasal microstream end-tidal carbon dioxide (EtCO₂) monitoring throughout the post-anesthesia care unit (PACU) stay.
Routine Monitoring
Other intervention
After extubation, the sampling line is placed between the patient's mouth and nose to deliver oxygen at 2 L/min. The patient receives routine monitoring including continuous pulse oximetry (SpO₂) and clinical observation, but is not connected to the EtCO₂ monitoring device.

Treatment groups

324 Participants

are divided into 2 treatment groups

Group A: Control Group (Routine Monitoring Group)Active comparator 1 intervention

Group B: Experimental Group (EtCO₂ Monitoring Group)Experimental treatment 1 intervention

Trial outcomes

Primary outcomes

Incidence of post-extubation hypoxemia (SpO₂ < 90% for >15 seconds)

Closely monitor vital signs, and record the number of episodes of hypoxemia (defined as SpO₂ \< 90% lasting for \>15 seconds) following tracheal extubation after the patient is transferred from the operating room to the PACU.more than 15 seconds

Time frame