Ultrasonography for Prediction of Difficult Intubation and Prediction of Endotracheal Tube Size

Istanbul University

Status: Unknown

Conditions: Intubation; Difficult or Failed

Treatments: Drug: fentanyl and rocuronium; Drug: Propofol; Drug: intravenous midazolam; Device: Ultrasonography; Drug: Sevoflurane

Study type: Interventional

Funder types: Other

Identifiers

NCT03013036

0964

Details and patient eligibility

About

Aim of our study is to evaluate the predictive value of ultrasonographic (USG) measurement of thyrohyoid distance for difficult intubation and determination of optimal endotracheal tube size by using USG in pediatric patients undergoing elective surgery.

Full description

After ethics committee approval and parental consent were obtained, 119 patients undergoing genitourinary surgery or inguinal hernia repair under general anesthesia, were included in study. Patients with head or neck anomalies, syndromic patients, patients undergoing emergency surgery and patients with a history of difficult airway were excluded from the study. Patients were grouped according to their ages; Group I (1-2 years,n=38), Group II (3-5 years,n=46) and Group III (6-8 years,n=35). USG measurements were performed following sevoflurane induction in groups I and II. In group III, USG measurements were performed following premedication with intravenous midazolam 0.05 mg/kg . Thyrohyoid distance, glottic and subglottic diameters were measured with ultrasonography. The size of the endotracheal tube according to Bae's formula ( internal diameter of Endotracheal tube = 0.705 x subglottic diameter - 0.091) was calculated and recorded. Before intubation, endotracheal tube (cuffed/uncuffed) was selected using age-related formulas. In group II, anaesthesia induction was achieved with propofol 2 mg/kg. In all groups, endotracheal intubation was achieved with fentanyl 2μg/kg and rocuronium 0.6 mg/kg. Endotracheal tube size was considered as optimal when a leak was detected at 20-30cmH₂O inflation pressures. If a resistance was felt in the subglottic region, the tube was exchanged with a smaller and was exchanged with a larger (0.5 mm) size if a leak occurred at inflation pressures lower than 20cmH₂O. Intubation duration , Cormack-Lehane scores and Intubation Difficulty Scale scores were recorded. For comparison of age related formula and Bae 's formula, only patients who were intubated with un-cuffed endotracheal tube were evaluated.

Enrollment: 150 estimated patients

Sex: All

Ages: 1 to 8 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Aged between 1 and 8 years
• Elective surgery

Exclusion criteria

• Patients with head or neck abnormalities
• Syndromic patients
• Emergency surgery and patients with a
• History of difficult airway
• Allergy to ultrasound gel

Trial design

Primary purpose: Prevention

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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150 participants in 3 patient groups

Group I

Other group

Description:

Patients between 1 and 2 years

Treatment:

Drug: Sevoflurane

Drug: fentanyl and rocuronium

Drug: intravenous midazolam

Device: Ultrasonography

Group II

Other group

Description:

patients between 3 and 5 years

Treatment:

Drug: Sevoflurane

Drug: fentanyl and rocuronium

Device: Ultrasonography

Drug: Propofol

Group III

Other group

Description:

patients between 6 and 8 years

Treatment:

Drug: Sevoflurane

Drug: fentanyl and rocuronium

Drug: intravenous midazolam

Device: Ultrasonography