Effects of Continuous Monitoring and Progressive Regulation of Inflatable Laryngeal Mask Airway Cuff Pressure on Postoperative Pharyngolaryngeal Complications in Elderly Patients

NCT07461467 | Recruiting DMC

• 1 other identifier: 2025-773-01
• Study Type: interventional
• Target: 146
• Locations: 1 country
• Sites: 1

Brief Summary

Currently, research on laryngeal mask airway (LMA) has been continuously deepened both domestically and internationally, which has greatly promoted the optimization process of clinical application and related management strategies. Numerous domestic and foreign research findings have consistently emphasized the key role of LMA cuff pressure monitoring in reducing postoperative complications, especially in alleviating sore throat and dysphagia. Foreign studies have extensively covered the research and development innovation of LMA devices, as well as comprehensive comparative analyses with other airway management methods such as endotracheal intubation, providing rich perspectives for expanding the application of LMA and improving its application effects. In contrast, domestic studies have distinct pertinence, focusing on application exploration in specific populations and clinical practice scenarios, and have provided important evidence for the safe and effective use of LMA in specific groups through in-depth research. However, it is undeniable that there are obvious deficiencies in both domestic and foreign research regarding the application of continuous monitoring and progressive regulation of LMA cuff pressure in elderly patients-a crucial field. Due to the natural decline of physiological functions, elderly patients face an increased risk of complications such as pulmonary and extrapulmonary complications, as well as pharyngolaryngeal complications, when using LMA during the perioperative period. Therefore, it is particularly urgent to carry out continuous pressure monitoring and progressive regulation of LMA cuff pressure, and to further explore the optimal range of LMA cuff pressure. This study will not only fill the current research gap but also provide solid support for the safe and efficient airway management of elderly patients during the perioperative period.

Conditions

LMA; Randomized Controlled Trial; Laryngeal Mask Airways; Pharyngolaryngeal Postoperative Pain; Cuff Pressure; Oropharyngeal Leak Pressure; Elderly (People Aged 65 or More)

Keywords

Elderly people; Laryngeal mask airways; pharyngolaryngeal complications; cuff pressure; Randomized Controlled Trial

Outcome Measures

Primary Outcomes (5)

• The incidence of postoperative pharyngeal pain

  Pharyngeal pain was evaluated using the Visual Analogue Scale (VAS), with a score ≥ 3 defined as the occurrence of pharyngeal pain.

  Before LMA insertion (Time 0), at LMA removal (Time 1), and 10 minutes (Time 2), 30 minutes (Time 3), 1 hour (Time 4), 2 hours (Time 5), 24 hours (Time 6), and 48 hours (Time 7) after LMA removal.

• The incidence of postoperative supraglottic pharyngeal mucosal injury

  Supraglottic pharyngeal mucosal injury was assessed using a fiberoptic bronchoscopy-based mucosal lesion grading system. An increase in the grade compared to that at LMA insertion was defined as the occurrence of mucosal injury.

  Baseline (before LMA insertion)；Intraoperative (at LMA insertion)；Intraoperative (at LMA removal)

• The incidence of postoperative hoarseness

  Hoarseness was graded according to a hoarseness severity scale, with a grade ≥ 1 defined as the occurrence of hoarseness.

  Before LMA insertion (Time 0), at LMA removal (Time 1), and 10 minutes (Time 2), 30 minutes (Time 3), 1 hour (Time 4), 2 hours (Time 5), 24 hours (Time 6), and 48 hours (Time 7) after LMA removal.

• The incidence of postoperative blood on the laryngeal mask airway (LMA) surface or in sputum

  Blood on the LMA surface was observed by the clinician removing the LMA, while blood in sputum was either observed by the clinician or self-reported by the patient/family.

  Before LMA insertion (Time 0), at LMA removal (Time 1), and 10 minutes (Time 2), 30 minutes (Time 3), 1 hour (Time 4), 2 hours (Time 5), 24 hours (Time 6), and 48 hours (Time 7) after LMA removal.

• The incidence of postoperative dysphagia

  Dysphagia/discomfort on swallowing was self-reported by the patient.

  Before LMA insertion (Time 0), at LMA removal (Time 1), and 10 minutes (Time 2), 30 minutes (Time 3), 1 hour (Time 4), 2 hours (Time 5), 24 hours (Time 6), and 48 hours (Time 7) after LMA removal.

Secondary Outcomes (3)

• The incidence of other perioperative airway complications

  Within 7 days postoperatively

• Incidence of pulmonary complications

  within 7 days and 30 days postoperatively

• Patient satisfaction

  On postoperative day 3

Study Arms (2)

Empirically inflated LMA

ACTIVE COMPARATOR

In group EI, anesthesiologists inflated the ILMA cuff based on their clinical experience using a 20 mL syringe, with the goal of achieving empirical inflation that ensured unobstructed ventilation. Subsequently, the cuff pressure was passively measured and recorded using a cuff pressure monitor, the measured pressure values were blinded to the anesthesiologists and no adjustments were made. This design ensured that group EI represented conventional empirical management with added observation only.

Other: Empirically inflated LMA

Regulated and monitored ILMA

EXPERIMENTAL

In group RM, the ILMA cuff was first inflated to 40cmH2O using a pressure monitor, followed by continuous monitoring. This initial pressure was chosen based on previous studies, pre-experimental data and clinical observation, which indicated that it was sufficiently high to ensure an OLP ≥ 25 cmH2O in the vast majority of pilot cases, thereby providing a safe and consistent starting point for downward regulation. Then the OLP was measured. OLP measurement method\[: manual positive-pressure ventilation mode, closed APL valve, 3 L/min oxygen flow, with plateau pressure at audible mouth leakage defined as OLP.

Other: Regulated and monitored ILMA

Interventions

Regulated and monitored ILMA OTHER

In group RM, the ILMA cuff was first inflated to 40cmH2O using a pressure monitor, followed by continuous monitoring. This initial pressure was chosen based on previous studies, pre-experimental data and clinical observation, which indicated that it was sufficiently high to ensure an OLP ≥ 25 cmH2O in the vast majority of pilot cases, thereby providing a safe and consistent starting point for downward regulation. Then the OLP was measured. OLP measurement method: manual positive-pressure ventilation mode, closed APL valve, 3 L/min oxygen flow, with plateau pressure at audible mouth leakage defined as OLP.

Regulated and monitored ILMA

Empirically inflated LMA OTHER

In group EI, anesthesiologists inflated the ILMA cuff based on their clinical experience using a 20 mL syringe, with the goal of achieving empirical inflation that ensured unobstructed ventilation. Subsequently, the cuff pressure was passively measured and recorded using a cuff pressure monitor, the measured pressure values were blinded to the anesthesiologists and no adjustments were made. This design ensured that group EI represented conventional empirical management with added observation only.

Empirically inflated LMA

Eligibility Criteria

• Age: 60 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged ≥ 60years;
• Non-cardiac, non-thoracic, and non-head and neck surgery;
• Non-laparoscopic surgery;
• Elective surgery;
• Surgical position: supine position ;
• American Society of Anesthesiologists (ASA) physical status classification Ⅰ-Ⅲ;
• New York Heart Association (NYHA) cardiac function classification Ⅰ-Ⅱ;
• Expected surgical duration ≥30 minutes and ≤ 2 hours;
• Body mass index (BMI) 18.5-30.0 kg/m2.

You may not qualify if:

• Preoperative predictable difficult airways, such as trismus, limited neck mobility, and other related conditions;
• Preoperative pharyngeal and laryngeal complications including sore throat, hoarseness, blood-tinged sputum, and dysphagia;
• Preexisting conditions such as loose teeth, laryngeal obstruction, laryngeal edema, acute airway inflammation, and gastrointestinal bleeding;
• Comorbidities of respiratory diseases like chronic obstructive pulmonary disease (COPD) and asthma;
• Allergies to ILMA materials (e.g., silicone, polyvinylchloride \[PVC\]);
• Inability to cooperate with the study for any reason;
• Participation in other clinical trials within 3 months prior to enrollment in this study;

Sponsors & Collaborators

• First Affiliated Hospital of Chongqing Medical University: lead

Study Sites (1)

The First Affiliated Hospital of Chongqing Medical University

Chongqing, Chongqing Municipality, 400016, China

RECRUITING

MeSH Terms

Interventions

Social Control, Formal

Intervention Hierarchy (Ancestors)

Health Care Economics and Organizations

Central Study Contacts

Su Min

CONTACT

13408631952; yangxuanqi1221@163.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: professor

Model Details: Individualized regulation proceeded as follows: (1) If OLP was ≥ 25 cmH2O: pressure was reduced in 2 cmH2O increments to the minimum value maintaining unobstructed ventilation, OLP ≥ 25 cmH2O, and cuff pressure ≥ peak airway pressure. If the OLP \< 25 cmH₂O: ILMA position was rechecked; with correct placement, pressure was increased in 5 cmH₂O increments until OLP ≥ 25 cmH₂O or 60 cmH₂O (safety limit). If OLP met the target after upward adjustment, downward regulation was performed as above. For regulation failure (OLP \< 25 cmH₂O at 60 cmH₂O) or persistent ILMA malposition, ILMA size was changed, or alternative supraglottic airway device/endotracheal intubation was used to ensure patient safety.

Study Record Dates

• First Submitted: February 12, 2026
• First Posted: March 10, 2026
• Study Start: November 2, 2025
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): March 1, 2027
• Last Updated: March 10, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)