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Airway Injuries After Intubation Using Videolaryngoscopy Versus Direct Laryngoscopy for Adult Patients Requiring Tracheal Intubation

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03613103
Recruitment Status : Recruiting
First Posted : August 2, 2018
Last Update Posted : December 2, 2019
IPS Universitaria-Universidad de Antioquia
Information provided by (Responsible Party):
Universidad de Antioquia

Brief Summary:

Abstract Background Successful tracheal intubation during general anesthesia requires a direct laryngoscope to retract the tongue and soft tissues of the mouth to achieve a line of sight for the larynx. Generally, Macintosh blade laryngoscopy is used to achieve the tracheal intubation. However, difficulties with the tracheal intubation arise the need to use alternative laryngoscopes that use digital or fiberoptic technology, to improve the larynx visibility. Among these devices, highly curved blade videolaryngoscope uses a curved blade to retract the soft tissues of floor of the mouth and transmits a video image to a screen, achieving better larynx visibility. Also, the decrease of the force in the soft tissues with videolaryngoscope could reduce airway injures.

Objectives Our primary objective is to assess whether use of videolaryngoscopy using highly curved blades for tracheal intubation in adults requiring general anesthesia reduces risk of airways injuries compared with Macintosh direct laryngoscopy. Our secondary aim is to assess postoperative satisfaction of the patients, successful intubation at the first attempt, successful global intubation, degree of larynx visibility according to classification Cormack - Lehane and time taken to perform intubation in videolaryngoscopy vs direct laryngoscopy. Finally, we assess the risk of presenting serious adverse event with the use of videolaryngoscopy compared with Macintosh laryngoscopy in hypoxemia, bradycardia and heart arrest.

Condition or disease Intervention/treatment Phase
Airway Trauma Airway Complication of Anesthesia Device: Video laryngoscopy Device: Direct laryngoscopy Not Applicable

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 716 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: A single-center randomized study is performed including non-cardiac surgical patients without predictable risk of difficult mask ventilation or of difficult tracheal intubation. For direct laryngoscopy group, we use a Macintosh blade and for videolaryngoscopy group we use videolaryngoscopy highly curved blade. Induction of anesthesia is performed using myorelaxation with rocuronium. We record each five minute the vital signs in the anesthesia record. The primary outcome is observed injuries in the mucosa of the airway: Erythema, edema, ecchymosis, laceration, excoriation and / or hematoma. Injuries to dental pieces: Partial and / or total loss of tooth integrity, loosening of dental piece, damage to dental and / or aesthetic prosthetic material. Laryngeal lesions: Edema, laceration, excoriation, erythema, ecchymosis and / or bleeding pharyngeal laryngeal mucosa, arytenoid luxation. Post-intubation symptoms: Sore throat, dysphonia and / or aphonia.
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Masking Description:

Participants will be assigned at the time of anesthetic induction in the surgery room. The allocation to the direct laryngoscopy group and the video laryngoscopy will be 1: 1 randomly using permuted blocks, generated by a computer operated by an external assistant to the investigation. The size of the blocks will be between 4, 6, and 8.

A person external to the research group will be responsible for concealment of allocation through opaque and sealed envelopes, listed sequentially.

Primary Purpose: Treatment
Official Title: Airway Injuries After Intubation Using Videolaryngoscopy Highly Curved Blades Versus Direct Laryngoscopy for Adult Patients Requiring Tracheal Intubation: a Randomized Controlled Trial
Actual Study Start Date : October 1, 2018
Estimated Primary Completion Date : June 1, 2020
Estimated Study Completion Date : June 1, 2020

Arm Intervention/treatment
Active Comparator: Direct laryngoscopy
Intubation with direct laryngoscopy (Conventional Intubation)
Device: Direct laryngoscopy
Intubation with direct laryngoscopy with macintosh blade

Experimental: Videolaryngoscopy
Intubation with videolaryngoscopy (Assisted video intubation)
Device: Video laryngoscopy
Intubation with videolaryngoscopy with highly curved blade

Primary Outcome Measures :
  1. Number of patients with an airway injury [ Time Frame: 24 hours ]

    Airway injury will be a composite outcome as follow: Injury in the oral cavity or injury in the laryngopharynx.

    These injuries will be evaluated using a digital camera of the oral cavity (fiber optical camera) in the immediate POP.

    A patient will be considered positive for the outcome If he/she has at least one of the following findings: Erythema, edema, ecchymosis, laceration, excoriation and / or hematoma in labial, jugal, gingival, lingual mucosa, hard and soft palate; Dental pieces injury: partial and / or total loss of the integrity of the dental piece; Larynx lesions: Edema, laceration, excoriation, erythema, ecchymosis and / or bleeding of pharyngeal laryngeal mucosa.

Secondary Outcome Measures :
  1. Successful intubation at the first attempt [ Time Frame: Immediate postoperative ]
    Number of patients with successful intubation at the first attempt.

  2. Global of Successful Intubation [ Time Frame: Immediate postoperative ]
    Number of patients with successful intubation regardless of the attempts to achieve it.

  3. Cormack-lehane visualization [ Time Frame: Immediate postoperative ]
    Degree of Cormack-lehane visualization in each patient. The degree of Cormack-Lehane visualization will be measured from I to IV in relation to the visible portion of the glottis; Grade I with total visualization and Grade IV without visualization of glottis.

  4. Time to achieve orotracheal intubation [ Time Frame: Immediate postoperative ]
    Time measured in seconds to achieve orotracheal intubation in each patient. The time interval is determined from the beginning of laryngoscopy by the anesthesiologist until the verification of tracheal intubation by capnography.

  5. Post-anesthetic satisfaction [ Time Frame: Immediate postoperative ]
    Post-anesthetic satisfaction in each patient. The Quality of Recovery scale 40 will be used to determine the degree of patient satisfaction, according to the overall and subglobal score, defined by five dimensions: patient support, comfort, emotional, physical independence and pain (includes anatomical airway site).

  6. Hypoxemia during induction and intubation [ Time Frame: Immediate postoperative ]
    Number of patients with hypoxemia during induction and intubation. Hypoxaemia is defined as an oxygen saturation measured with pulse oximetry less than 92%.

  7. Bradycardia during induction and intubation [ Time Frame: Immediate postoperative ]
    Number of patients with bradycardia during induction and intubation. Bradycardia is defined as a decrease in heart rate of less than 40 beats / minute.

  8. Cardiac Arrest [ Time Frame: Immediate postoperative ]
    Number of patients presenting cardiac arrest. Cardiac arrest is defined as the presence of any malignant rhythm: Ventricular tachycardia, ventricular fibrillation, asystole or pulseless electrical activity plus loss of carotid pulse for more than 10 seconds.

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Over 18 years of age.
  • Scheduled for a procedure or surgery that requires general anesthesia that requires orotracheal intubation.
  • Scheduled for non-cardiac surgery.
  • Elective surgery.

Exclusion Criteria:

  • Women in pregnancy.
  • Patient refuses to participate in the study before surgery.
  • Patients with predictors of anticipated difficult airway.
  • Head and neck surgery.
  • Go to Intensive Care Unit with endotracheal intubation.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03613103

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Universidad de Antioquia Recruiting
Medellin, Antioquia, Colombia
Contact: Fabian Casas, MD    054 4441333 ext 2510   
Sponsors and Collaborators
Universidad de Antioquia
IPS Universitaria-Universidad de Antioquia
Publications of Results:
Richard M. Levitan M, Scott D. Cook-Sather M, E. Andrew Ochroch M. Demystifying Direct Laryngoscopy and Intubation. Hosp Physician [Internet]. 2000;1(59):47-56. Available from:

Other Publications:
Jonathan Benumof CAH. Benumof and Hagberg's Airway Management - Jonathan Benumof, Carin A. Hagberg [Internet]. Third Edit. Carin A. Hagberg (The University of Texas MS at H, editor. Elsevier. Philadelphia, PA 19103-2899: Elsevier Inc; 2013. 1142 p. Available from:
Kaplan MB, Ward DS, Berci G. A new video laryngoscope-an aid to intubation and teaching. J Clin Anesth [Internet]. 2002 Dec [cited 2017 Jan 25];14(8):620-6. Available from:
Turkstra TP, Pelz DM, Jones PM. Cervical Spine Motion. Anesthesiology [Internet]. 2009 Jul [cited 2017 Jan 25];111(1):97-101. Available from:
Graham B, Kamal RN, Marks M, Herren DB, Vlieland TPV, Simmen BR, et al. Defining and Measuring Patient Satisfaction. J Hand Surg Am [Internet]. 2016 Sep [cited 2016 Dec 13];41(9):929-31. Available from:
Castellanos-Olivares DA, Evangelina-Cervantes DH, Vásquez-Márquez DPI. Satisfacción anestésica como indicador de calidad de la atención médica en el paciente geriátrico. Rev Mex Anestesiol [Internet]. 2013;36(1):250-5. Available from: /
RSarah F. Barnett MBB. BS. Patient-Satisfaction Measures in Anesthesia: Qualitative Systematic Review. Anesthesiology. 2016;119(3):570-87.
Cormack RS, Lehane J. Difficult tracheal intubation in obstetrics. Anaesthesia [Internet]. 1984 Nov [cited 2017 Jan 25];39(11):1105-11. Available from:
Invima - Instituto Nacional de Vigilancia de Medicamentos y Alimentos., Ministerio de Protección Social. Resolución No. 8430 del 4 de Octubre de 1993 - Por la cual se establecen las normas científicas, técnicas y administrativas para la investigación en salud. [Internet]. [cited 2017 Jan 20]. Available from:
La MDE, Social P. Ministerio De La Proteccion Social Resolucion número 2378 De 2008. 2008;2004(1271):1-10.
Humanidades D De, Apartado B, España P. Universidad de Navarra Centro de Documentación de Bioética Declaración de Helsinki de la AMM - Principios éticos para las investigaciones médicas en seres humanos. 2013;1-8
Favaloro A. Pautas éticas internacionales para la investigación biomédica en seres humanos [Internet]. Index Infectológico. 2008. 1-119 p. Available from:
Emanuel EJ, Wendler D, Grady C. What Makes Clinical Research Ethical? J Am Med Assoc [Internet]. 2000;283(20):2701-11. Available from:

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Responsible Party: Universidad de Antioquia Identifier: NCT03613103    
Other Study ID Numbers: Airway - 001
First Posted: August 2, 2018    Key Record Dates
Last Update Posted: December 2, 2019
Last Verified: November 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Universidad de Antioquia:
video laryngoscopy
direct laryngoscopy