Cervical Spine Biomechanics During Endotracheal Intubation

NCT01369381 | Completed DMC

• 2 other identifiers: 201102721R01EB012048
• Study Type: interventional
• Target: 14
• Locations: 1 country
• Sites: 1

Brief Summary

Current methods for endotracheal intubation in the presence of cervical spine (c-spine) instability are not evidence-based. This is so because the relationships between the forces applied during intubation (by the laryngoscope) and the resulting c-spine movement have not yet been quantitatively characterized. As a result, with the current level of knowledge, it is not known, and it is not possible to predict, which types of c-spine instability have the greatest risk of cervical spinal cord injury with intubation. This shortcoming makes it impossible to know which intubation devices and techniques are likely to be safest in the presence of c-spine instability. To address this critical lack of knowledge, the overarching purpose of the proposed research is to: 1) quantitatively relate c-spine movement that results from the forces applied to the peri-airway tissues during intubation (force-motion relationships), and 2) use these data to develop a mathematical model of the c-spine that will predict which types of c-spine instability result in the greatest amount of abnormal c-spine motion and associated spinal cord compression during intubation. This clinical study will utilize laryngoscope blades that are instrumented with a high resolution pressure mapping system to make high-resolution measurements of the forces and pressures of intubation while making simultaneous measurements of c-spine motion. In this study, study subjects will be intubated using both a conventional (Macintosh) laryngoscope and an alternative (Airtraq) laryngoscope. By using two different laryngoscopes, we, the investigators, will introduce forces of differing magnitudes and distributions to peri-airway tissues. The Airtraq does not require a direct line of sight to visualize the vocal cords, and among the various new alternative laryngoscopes it is the only one that has been shown to result in 30-50% less cervical motion than a conventional (Macintosh) laryngoscope. Accordingly, we hypothesize 1) 30-50% less force will be applied with the Airtraq laryngoscope than with the conventional (Macintosh) laryngoscope and 2) 30-50% less c-spine motion will occur with the Airtraq. By studying (intubating) each subject twice, any differences in the c-spine force-motion relationships between devices will be due to the devices themselves. By studying each subject twice, we can account for (and eliminate) differences among study subjects in c-spine biomechanical properties.

Conditions

Spinal Diseases; Other Biomechanical Lesions of Cervical Region; Tracheal Intubation Morbidity

Keywords

Cervical spine; Endotracheal intubation; Laryngoscope; Biomechanics

Outcome Measures

Primary Outcomes (1)

• Cervical spine segmental intervertebral motion

  Lateral fluoroscopy is used to measure cervical spine motion during endotracheal intubation.

  Data collection takes place during two sequential endotracheal intubations (40-45 seconds), with follow-up assessments on postoperative days 1, 3, and 7.

Secondary Outcomes (2)

• Laryngoscope blade force distribution

  Data collection takes place during two sequential endotracheal intubations (40-45 seconds), with follow-up assessments on postoperative days 1, 3, and 7.

• Glottic visualization

  Data collection takes place during two sequential endotracheal intubations (40-45 seconds), with follow-up assessments on postoperative days 1, 3, and 7.

Study Arms (2)

Airtraq laryngoscope

EXPERIMENTAL

The Airtraq is an alternative indirect laryngoscope that appears to cause less cervical spine motion during intubation that conventional direct laryngoscopy (Macintosh blade)

Procedure: Endotracheal intubation

Macintosh laryngoscope

ACTIVE COMPARATOR

This arm constitutes intubation with a conventional direct laryngoscopy with a Macintosh blade which has been shown to result in cervical spine extension, particularly in the upper cervical segments.

Procedure: Endotracheal intubation

Interventions

Endotracheal intubation PROCEDURE

Study patients undergo endotracheal intubation using both a conventional direct laryngoscope (Macintosh) and an alternative indirect laryngoscope (Airtraq). The order of intubation (Macintosh then Airtraq--or--Airtraq then Macintosh) is randomized.

Airtraq laryngoscope; Macintosh laryngoscope

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patient Height: 5-feet, 0-inches to 6-feet, 0-inches
• Patient body mass index: less than 30 kg/m2
• Planned surgery requires use of C-arm fluoroscopy
• Planned surgery to take place at University of Iowa and requires general anesthesia and orotracheal intubation

You may not qualify if:

• The patient is a prisoner
• The patient is pregnant
• The patient is not competent to personally give consent
• Neurological signs and symptoms indicating cervical spinal cord myelopathy
• Cervical spine images demonstrating anatomic instability, traumatic injury, significant cervical stenosis, and/or spinal immobility
• Condition associated with cervical spine anatomic abnormalities such as Rheumatoid arthritis, Down Syndrome, Ankylosing spondylitis, Osteogenesis imperfecta
• Prior cervical spine surgery of any type
• History of difficult endotracheal intubation
• Currently symptomatic gastroesophageal reflux disease
• Currently symptomatic asthma or other reactive airway disease
• Any history of coronary artery disease
• Any history of cerebral aneurysm(s)
• History of vocal cord and/or glottic disease or dysfunction
• Contraindication to receiving 100% oxygen
• Systolic blood pressure greater than 180 mmHg

Sponsors & Collaborators

• University of Iowa: lead
• National Institute for Biomedical Imaging and Bioengineering (NIBIB): collaborator
• Colorado State University: collaborator

Study Sites (1)

University of Iowa Hospitals and Clinics

Iowa City, Iowa, 52242, United States

Location

Related Publications (6)

• LeGrand SA, Hindman BJ, Dexter F, Weeks JB, Todd MM. Craniocervical motion during direct laryngoscopy and orotracheal intubation with the Macintosh and Miller blades: an in vivo cinefluoroscopic study. Anesthesiology. 2007 Dec;107(6):884-91. doi: 10.1097/01.anes.0000291461.62404.46.

  PMID: 18043056 BACKGROUND

• Santoni BG, Hindman BJ, Puttlitz CM, Weeks JB, Johnson N, Maktabi MA, Todd MM. Manual in-line stabilization increases pressures applied by the laryngoscope blade during direct laryngoscopy and orotracheal intubation. Anesthesiology. 2009 Jan;110(1):24-31. doi: 10.1097/ALN.0b013e318190b556.

  PMID: 19104166 BACKGROUND

• Hindman BJ, Palecek JP, Posner KL, Traynelis VC, Lee LA, Sawin PD, Tredway TL, Todd MM, Domino KB. Cervical spinal cord, root, and bony spine injuries: a closed claims analysis. Anesthesiology. 2011 Apr;114(4):782-95. doi: 10.1097/ALN.0b013e3182104859.

  PMID: 21326090 BACKGROUND

• Hirabayashi Y, Fujita A, Seo N, Sugimoto H. A comparison of cervical spine movement during laryngoscopy using the Airtraq or Macintosh laryngoscopes. Anaesthesia. 2008 Jun;63(6):635-40. doi: 10.1111/j.1365-2044.2008.05480.x.

  PMID: 18477276 BACKGROUND

• Turkstra TP, Pelz DM, Jones PM. Cervical spine motion: a fluoroscopic comparison of the AirTraq Laryngoscope versus the Macintosh laryngoscope. Anesthesiology. 2009 Jul;111(1):97-101. doi: 10.1097/ALN.0b013e3181a8649f.

  PMID: 19512871 BACKGROUND

• Hindman BJ, Dexter F, Gadomski BC, Puttlitz CM. Relationship Between Glottic View and Intubation Force During Macintosh and Airtraq Laryngoscopy and Intubation. Anesth Analg. 2022 Oct 1;135(4):815-819. doi: 10.1213/ANE.0000000000006082. Epub 2022 May 13.

  PMID: 35551148 DERIVED

MeSH Terms

Conditions

Spinal Diseases

Interventions

Intubation, Intratracheal

Condition Hierarchy (Ancestors)

Bone Diseases; Musculoskeletal Diseases

Intervention Hierarchy (Ancestors)

Airway Management; Therapeutics; Intubation; Investigative Techniques

Study Officials

• Bradley J Hindman, M.D.

  University of Iowa

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor, Department of Anesthesia

Study Record Dates

• First Submitted: May 31, 2011
• First Posted: June 8, 2011
• Study Start: December 1, 2011
• Primary Completion: July 1, 2012
• Study Completion: July 1, 2012
• Last Updated: August 7, 2012

Record last verified: 2012-08

Locations

US (1)