Macintosh Blade Size for Endotracheal Intubation in Operative Rooms (MacSize_OR)

Macintosh Blade Size During Laryngoscopy for Endotracheal Intubation in Operative Rooms. A Nationwide Prospective Observational Study.

Endotracheal intubation is a frequent procedure in the operating room but optimal Macintosh blade size remains unknown to date.

Study Overview

• Status: Not yet recruiting
• Conditions: Endotracheal Intubation; Intubation Complication; Intubation; Difficult or Failed
• Intervention / Treatment: Device: Direct laryngoscopy using Macintosh blade

Detailed Description

Endotracheal intubation is an extremely frequent procedure in the operating room, in intensive care units and in emergency medicine (in- or out-of-hospital). Apart from special cases of foreseen difficult programmed intubation, direct laryngoscopy remains the most frequently used technique. It requires the use of a handle (short or long), which serves as a light source on which is adapted a Macintosh curved blade, metallic or plastic, single or multiple use. The choice of blade size is based on the experience of the physician. Most often, in adult settings, size 3 or 4 blades are used. The very spartan literature on the subject and the current recommendations do not provide any information on the choice of blade size. Our team (and others) recently concluded that intubation first attempt rates in intensive care units or emergency settings were improved when using shorter Macintosh blade size No3 vs 4 (Godet et al. Intensive Care Medicine 2022 and Landefeld et al. Critical Care Explorations 2023). We therefore wish to evaluate these practices in terms of success of the first laryngoscopy, Cormack-Lehane and POGO (percentage of glottic opening visualized) scores, the need to use an alternative technique or a second operator in operative rooms. The results will be analyzed with regard as a function and experience of the person performing the laryngoscopy, as well as the setting (urgent or scheduled). These data are usually collected during the performance of an endotracheal intubation in a nationwide fashion in French operative rooms.

• Study Type: Observational
• Enrollment (Estimated): 3000

Contacts and Locations

• Study Contact: Name: Thomas Godet, MD, PhD; Phone Number: +33473755170; Email: tgodet@chu-clermontferrand.fr
• Study Contact Backup: Name: Dominique Morand, PhD; Phone Number: +33684894678; Email: dmorand@chu-clermontferrand.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Any patient requiring orotracheal intubation with direct laryngoscopy in first place

Description

Inclusion Criteria:

• Patients must be admitted in a participating operative room and require mechanical ventilation through an orotracheal tube.
• Adult (age ≥ 18 years)
• Subjects must be covered by public health insurance
• Written informed consent from the patient or proxy (if present) before inclusion or once possible when patient has been included in a context of emergency.

Exclusion Criteria:

• Anticipated difficult intubation requiring videolaryngoscopy or other technic in first place
• Nasotracheal intubation
• Refusal of study participation or to pursue the study by the patient
• Absence of coverage by the French statutory healthcare insurance system
• Protected person

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Macintosh blade size 3; Patients intubated using Macintosh blade size 3	Device: Direct laryngoscopy using Macintosh blade; Patients in operative room requiring direct laryngoscopy for endotracheal intubation
Macintosh blade size 4; Patients intubated using Macintosh blade size 4	Device: Direct laryngoscopy using Macintosh blade; Patients in operative room requiring direct laryngoscopy for endotracheal intubation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of patients with successful first-pass orotracheal intubation	The proportion of patients with successful first-pass orotracheal intubation	At intubation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Moderate complications related to intubation_difficult intubation	Rate of difficult intubation	At intubation
Moderate complications related to intubation_arrythmia	Rate of severe ventricular or supraventricular arrhythmia requiring intervention	At intubation
Moderate complications related to intubation_oesophageal intubation	Rate of oesophageal intubation	At intubation
Moderate complications related to intubation_agitation	Rate of agitation	At intubation
Moderate complications related to intubation_aspiration	Rate of pulmonary aspiration	At intubation
Moderate complications related to intubation_dental injuries	Rate of dental injuries	At intubation
Difficulty of intubation	Rate of operator-assessed difficulty of intubation	During intubation
Additional airway equipment	Rate of need for additional airway equipment (video laryngoscope, bougie, stylet, fibroscope, cricothyrotomy)	During intubation
Additional second operator	Rate of need for a second operator	During intubation
Severe complications related to intubation_hypoxemia	Rate of severe hypoxemia defined by lowest oxygen saturation (SpO2) < 90 %	At intubation
Severe complications related to intubation_severe collapse	Rate of cardiovascular collapse, defined as systolic blood pressure less than 80 mmHg systolic blood pressure less than 50 mmHg recorded at least once	At intubation
Severe complications related to intubation_cardiac arrest	Rate of cardiac arrest related to intubation	At intubation
Severe complications related to intubation_death	Rate of death related to intubation	At intubation
Cormack Lehane	Cormack-Lehane grade of glottic view	During laryngoscopy
Percentage of Glottic Opening	Percentage of Glottic Opening (POGO) grade of glottic view	During laryngoscopy

Collaborators and Investigators

• Sponsor: University Hospital, Clermont-Ferrand
• Collaborators: Société Française d'Anesthésie-Réanimation (SFAR)
• Investigators: Principal Investigator: Thomas Godet, MD, PhD, Clermont-Ferrand University Hospitals

Publications and helpful links

General Publications

• Godet T, De Jong A, Garin C, Guerin R, Rieu B, Borao L, Pereira B, Molinari N, Bazin JE, Jabaudon M, Chanques G, Futier E, Jaber S. Impact of Macintosh blade size on endotracheal intubation success in intensive care units: a retrospective multicenter observational MacSize-ICU study. Intensive Care Med. 2022 Sep;48(9):1176-1184. doi: 10.1007/s00134-022-06832-9. Epub 2022 Aug 16.
• Landefeld KR, Koike S, Ran R, Semler MW, Barnes C, Stempek SB, Janz DR, Rice TW, Russell DW, Self WH, Vonderhaar D, West JR, Casey JD, Khan A. Effect of Laryngoscope Blade Size on First Pass Success of Tracheal Intubation in Critically Ill Adults. Crit Care Explor. 2023 Mar 6;5(3):e0855. doi: 10.1097/CCE.0000000000000855. eCollection 2023 Mar.

Study record dates

Study Major Dates

• Study Start (Estimated): February 1, 2024
• Primary Completion (Estimated): June 1, 2024
• Study Completion (Estimated): July 1, 2024

Study Registration Dates

• First Submitted: January 10, 2024
• First Submitted That Met QC Criteria: January 22, 2024
• First Posted (Actual): January 31, 2024

Study Record Updates

• Last Update Posted (Actual): January 31, 2024
• Last Update Submitted That Met QC Criteria: January 22, 2024
• Last Verified: January 1, 2024

More Information

Terms related to this study

• Keywords: Complications; Intubation; Video Laryngoscopy; Macintosh; Direct Laryngoscopy; Operative Room
• Other Study ID Numbers: IRB 00010254-2023-081

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data available upon reasonable request and satisfactory presented analysis plan. Authorship will include principal investigator (last author).
• IPD Sharing Time Frame: Data available after study completion and publication
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No