Effect of Transnasal Microstream Capnography on Incidence of Hypoxemia During Emergence From General Anesthesia in Elderly Patients After Abdominal Surgery: A Prospective Randomised Controlled Trial
Trial Snapshot
- Phase
- Not Applicable
- Status
- Not yet recruiting
- Sponsor
- Enrollment
- 324
Study Overview
Brief Summary
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).
Detailed Description
Study Title:
Effect of Transnasal Microstream End-Tidal Carbon Dioxide Monitoring on the Incidence of Postoperative Hypoxemia in Elderly Patients Undergoing Laparoscopic Surgery under General Anesthesia with Endotracheal Intubation: A Prospective, Randomized Controlled Study
Principal Investigator: Wu Jianbo Department: Anesthesiology and Perioperative Medicine
Background & Objective:
Postoperative hypoxemia is a common respiratory complication in the post-anesthesia care unit (PACU). Conventional pulse oximetry (SpO₂) has a delayed response to hypoventilation, especially during supplemental oxygen therapy. This study aims to investigate whether adding transnasal microstream end-tidal carbon dioxide (EtCO₂) monitoring in the PACU reduces the incidence of hypoxemia in elderly patients after laparoscopic surgery under general anesthesia.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Prevention
- Masking
- Triple (Participant, Investigator, Outcomes Assessor)
Masking Description
This is a partially masked (single-blind) study. Participants (under sedation and unaware of group assignment), outcome assessors, and the statistician are masked to group allocation. The anesthesia provider who performs the intervention cannot be masked because the EtCO₂ monitoring interface is visible only in the experimental group. Randomization is concealed using sequentially numbered, sealed, opaque envelopes, and the allocation is revealed after extubation just before the intervention. The statistician receives only coded data (Group A/B) and remains blinded until the final analysis is completed.
Eligibility Criteria
- Ages
- 65 Years to 80 Years (Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •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;
- •Willing to participate in the study and provide written informed consent
Exclusion Criteria
- •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);
- •Severe cardiac insufficiency (≤4 Metabolic Equivalents [MetS]);
- •Severe renal insufficiency (acute kidney injury [AKI] or chronic kidney disease [CKD] stage 4 or higher);
- •Severe hepatic insufficiency (Child-Pugh class C or worse);
- •Allergy to study medications;
- •Daily alcohol intake ≥60 grams;
- •History of psychiatric disorders such as depression, severe central nervous system depression, Parkinson's disease, basal ganglion lesions, schizophrenia, epilepsy, Alzheimer's disease;
- •Participation in another related clinical study within the past 3 months.
Investigators
Jianbo Wu
Department Director
Qianfoshan Hospital