Effects of Different Inspiratory:Expiratory Ratios on Respiratory and Recovery Outcomes During Dental Procedures Under General Anesthesia in Pediatric Patients

Official title

A Clinical Study on the Effects of Different Inspiratory:Expiratory Ratios on Respiratory Function and Recovery in Pediatric Patients Undergoing Dental Procedures Under General Anesthesia

Overview

This observational study aims to evaluate the effects of different inspiratory to expiratory (I:E) ratios (1:2 vs. 1:3) during mechanical ventilation in pediatric patients undergoing dental procedures under general anesthesia. Due to behavioral challenges, dental phobia, or medical conditions, general anesthesia is often required to ensure immobility and cooperation during dental treatments in children. In the clinic where the study will be conducted, the I:E ratio is routinely adjusted approximately 20-30 minutes before the end of the procedure to facilitate a smoother transition to spontaneous breathing during emergence from anesthesia. While 1:2 is commonly used, the 1:3 ratio may improve respiratory efficiency and recovery by prolonging the expiratory phase. The study aims to compare vital signs, respiratory parameters (heart rate, blood pressure, SpO₂, EtCO₂, respiratory rate), recovery quality, and respiratory complications between the two I:E ratios. The findings aim to optimize ventilation strategies and improve patient comfort and safety during emergence from anesthesia.

Detailed description

The recent study involves pediatric patients undergoing dental procedures under general anesthesia following routine and standard clinical protocols. No additional interventions beyond standard care will be applied.

Specifically for the study, a non-invasive, observational scoring system will be used during the emergence phase to assess respiratory quality without requiring any extra tests or procedures. The scoring includes observation of spontaneous breathing, accessory muscle use, airway patency, physical responses to painful stimuli, and coughing episodes.

Patients will receive the same anesthesia and dental treatment as those not included in the study. The study compares the effects of routine inspiratory:expiratory (I:E) ratios used during mechanical ventilation on respiratory and recovery outcomes.

Variables assessed include vital and respiratory parameters (heart rate, blood pressure, SpO₂, EtCO₂, respiratory rate, peak airway pressure, time to spontaneous breathing, and physical/hemodynamic responses during spontaneous breathing), respiratory quality post-extubation (evaluated via the study-specific scale), and recovery parameters (physical responses during airway suctioning/extubation, presence of bronchospasm/ laryngospasm, agitation levels measured preoperatively by Modified Yale Preoperative Anxiety Scale and postoperatively by the Pediatric Anesthesia Emergence Delirium Scale (PAED), Modified Aldrete score, and discharge times from recovery and hospital wards).

All data will be recorded in a patient tracking form prepared for the study. Induction, maintenance, emergence from anesthesia, and management of any complications will follow routine clinical practice without any changes. No modifications to anesthesia or dental treatment protocols will be required for the study.

Primary outcome measures

• Post-Extubation Respiratory Quality [Time frame: During 10 minutes after extubation]
• Respiratory Rate (RR) [Time frame: During the emergence preparation period (approximately 25-35 minutes prior to extubation, up to 40 minutes if required)]
• Peak Airway Pressure (PeakP) [Time frame: During the emergence preparation period (approximately 25-35 minutes prior to extubation, up to 40 minutes if required)]
• Heart Rate [Time frame: During the emergence preparation period (approximately 20-30 minutes prior to extubation, up to 40 minutes if required)]
• Blood Pressure [Time frame: During the emergence preparation period (approximately 20-30 minutes prior to extubation, up to 40 minutes if required)]

Secondary outcome measures (6)

• Physical Response During Extubation [Time frame: From 2 minutes before extubation to 2 minutes after extubation]
• Occurrence of Bronchospasm or Laryngospasm [Time frame: From extubation until 30 minutes after extubation]
• Preoperative Anxiety Level Assessed by the Modified Yale Preoperative Anxiety Scale (mYPAS) [Time frame: Immediately before surgery (prior to operating room entry)]
• Pediatric Anesthesia Emergence Delirium (PAED) Score [Time frame: From emergence from anesthesia through recovery unit stay until discharge, assessed up to 1 hour]
• Modified Aldrete Score [Time frame: From emergence from anesthesia through recovery unit stay until discharge, assessed up to 1 hour]
• Postoperative transfer times [Time frame: From end of surgery until transfer to the hospital ward, assessed up to 2 hours]

Eligibility criteria

Inclusion criteria

• Pediatric patients scheduled for dental procedures under general anesthesia at our faculty.
• American Society of Anesthesiologists (ASA) Physical Status I or II.
• Age between 2 and 12 years.
• Written informed consent obtained from parents or legal guardians.

Exclusion criteria

• Patients whose parents or legal guardians decline participation.
• Presence of adenoid hypertrophy >30%.
• Macroglossia or retrognathia.
• Severe obesity or developmental delay.
• History of delayed emergence from anesthesia.
• ASA Physical Status III or higher.
• Anesthesia duration less than 1 hour or more than 3 hours.
• Patients with difficult airway management or ventilation.
• Known pulmonary or airway diseases or anomalies.
• Use of pharmacological agents that may affect spontaneous respiratory quality.
• Presence of neuromuscular disorders affecting respiratory function.
• Age <2 years or >12 years.
• Administration of medications intraoperatively or preoperatively that may influence respiratory dynamics during emergence (e.g., atropine, lidocaine, steroids).

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Observational model

Cohort

Study locations

Turkey (Türkiye) · 1 center

• Kırıkkale University, Faculty of Dentistry — Kirikkale

Identifiers

NCT: NCT07323420 · KU-ERKAN-004

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗