Miller Blade for Intubation in Adults

NCT ID: NCT05494463

Last Updated: 2026-01-06

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 1130 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2022-05-20
• Study Completion Date: 2023-02-01

Brief Summary

The study compares laryngeal view obtained with standard Macintosh blade laryngoscope and Miller blade laryngoscope in adult patients. After introduction to general anesthesia anesthesiologist will perform laryngoscopy with one chosen blade and after evaluation of visualisation of entrance to larynx will change blade to second one and repeat evaluation.

Detailed Description

Tracheal intubation is the gold standard of the airway in the operating theater in patients undergoing general anesthesia for surgery, in intensive care and emergency medicine, in patients with severe respiratory failure, which is life-threatening. The laryngoscope is a device used to visualize the entrance to the airway and the subsequent insertion of the tracheal tube into the trachea and main bronchus. Macintosh and Miller laryngoscopes have been used in clinical practice for several decades. The Macintosh laryngoscope is most commonly used for the intubation of adult patients, and the Miller laryngoscope for the intubation of newborns, including premature babies and pediatric patients. Currently, when we are dealing with the sars covid-19 virus epidemic and a large number of patients with respiratory failure requiring endotracheal intubation and replacement ventilation, searching for a device that facilitates endotracheal intubation, especially by people with little experience in using it, in the absence of anesthesiologists, seems to be justified. The aim of the study will be to assess the possibility of using the Miller's laryngoscope for intubation of adult patients and to compare it with the most frequently used Macintosh laryngoscope in this group of patients. The study will include patients scheduled for elective surgery under general endotracheal anesthesia. After a typical induction of anesthesia with the use of short-term intravenous anesthetics, opioids and muscle relaxants, appropriate for the planned surgery and a specific patient, after obtaining complete neuromuscular blockade, a Macintosh laryngoscope will be inserted to perform direct laryngoscopy and assess the exit to the respiratory tract with the help of the Cormack scale. Then the laryngoscope will be removed, the patient will receive active oxygen therapy to increase blood oxygenation to the value of 99-100%, and then an additional dose of intravenous anesthetic will be administered and a second direct laryngoscopy will be performed with the Miller's laryngoscope with a subsequent assessment of airway entry using the scale Cormack. The patient will then be intubated and connected to an anesthesia machine.

Conditions

Intubation Complication

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: DIAGNOSTIC
• Blinding Strategy: NONE

Study Groups

Macintosh blade

laryngoscopy with Macintosh blade

Group Type: NO_INTERVENTION

No interventions assigned to this group

Miller blade

laryngoscopy with Miller blade in the same patient

Group Type: ACTIVE_COMPARATOR

Miller blade

Intervention Type: DEVICE

After laryngoscopy with Macintosh blade patient will be evaluated in laryngoscopy with Miller blade

Interventions

Miller blade

After laryngoscopy with Macintosh blade patient will be evaluated in laryngoscopy with Miller blade

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• all patients scheduled for elective procedures under general anesthesia with endotracheal intubation

Exclusion Criteria

• patients with expected difficutl intubation requiring advanced intubation techniques
• with injuries of the cervical spine, or for surgery in the cervical spine
• patients with increased intracranial and intraocular pressure, with vascular changes in the CNS and other parts of the body
• patients with ASA III and above
• patients who do not consent to participate in the study

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 90 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Medical University of Lodz

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Medical University of Lodz, Poland

Lodz, , Poland

Countries

Poland

References

Ratajczyk P, Kluj P, Szmyd B, Resch J, Hogendorf P, Durczynski A, Gaszynski T. A Comparison of Miller Straight Blade and Macintosh Blade Laryngoscopes for Intubation in Morbidly Obese Patients. J Clin Med. 2024 Jan 24;13(3):681. doi: 10.3390/jcm13030681.

Reference Type: DERIVED

PMID: 38337375 (View on PubMed)

Other Identifiers

RNN/103/22/KE

Identifier Type: -

Identifier Source: org_study_id