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Completed

NCT Number: NCT04168840

Ultrasound Parameters to Predict Difficult Airway

Ultrasound has become an essential tool for the daily work of any doctor, but in certain specialties such as Anaesthesiology, its use has greatly increased the safety offered to patients throughout the perioperative period, either to perform nerve blocks, for vascular access, intraoperative hemodynamic management or any other use that allows increasing quality of care.

The management of the upper airway and the diagnosis of pathological conditions are essential skills for any doctor especially for Anaesthesiologist, ER physician, or Intensive Care physician. Because an inadequate airway management continues to be an important contributor to patient mortality and morbidity, any tool that can improve it should be considered as an addition to conventional clinical evaluation.

Unfortunately, most of the clinical parameters that should allow us to assess a potential difficult airway, do not always lead us to an adequate prediction, that is why US(Ultrasound) is use as an emerging tool in many fields, is also gathering strength in this search for a definitive predictor parameter.

Ultrasound has many obvious advantages (safe,fast, repeatable, portable, widely available and gives dynamic images in real time).

Sonographic studies are operator-dependent and although the identification of basic structures could be acquired with only a few hours of training, but more complex studies require a learning curve of months or even years. The high frequency linear probe (5-14 MHz) is probably the most suitable for the airway because images are of superficial structures (within 0-5 cm below the skin surface).

The growing academic interest in the use of US to look for predictors of difficult airway is centred mainly on measurements at the level of pretracheal tissues.

But the greatest limitation of these studies is the disparity of the fat distribution that exists between different ethnic groups and and sexes, and the lack of standardization method in patient´s intubation conditions.

So, the investigator propose to assess different ultrasound windows at the level of pretracheal tissues such as independent predictors of Difficult Airway.

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Key information

Age range

18 year–90 year

Sex eligibility

All sexes

Study type

Observational

Primary location

Clinica Universidad de Navarra

Madrid, 28027, Spain

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Patients (male or female) ASA I-III, aged between 18 and 90 years, undergoing scheduled surgery requiring orotracheal intubation. The signature of the informed consent is required authorizing its inclusion in the study.

Exclusion criteria

  • Obesity class II defined as a BMI greater than 35.
  • Pregnant.
  • Cervical tumors, goiter or patients who have required radiotherapy at the cervical level
  • Abnormalities that condition anatomy alterations such as facial / cervical fractures.
  • Maxillofacial abnormalities
  • People who cannot give their consent.

Treatment and study plan

Compare clinical test with ultrasound parameters

Diagnostic Test

Compare various clinical test with four ultrasound parameters to predict difficult intubation.

Primary outcomes

  1. Anterior neck soft tissue thickness measured by ultrasound at hyoid bone

    Time frame: 5 minutes

    Distance from skin to the midline of hyoid bone measure with lineal ultrasound probe

  2. Anterior neck soft tissue thickness measured by ultrasound at thyrohyoid membrane

    Time frame: 5 minutes

    Distance from skin to midline of epiglottis measure with lineal ultrasound probe

  3. Anterior neck soft tissue thickness measured by ultrasound at anterior commissure of vocal cords

    Time frame: 5 minutes

    Distance from skin to anterior commisure of vocal cords measure with lineal ultrasound probe

  4. Anterior neck soft tissue thickness measured by ultrasound at thyrohyoid membrane. Preepiglottic Area.

    Time frame: 5 minutes

    Calculated with distance from skin to midline of epiglottis and 1 centimeterto left and right side.

Secondary outcomes

  1. Modified Mallampati Score

    Time frame: 1 minute

    Class I: Soft palate, uvula, fauces, pillars visible. Class II: Soft palate, major part of uvula, fauces visible. Class III: Soft palate, base of uvula visible. Class IV: Only hard palate visible. Class I is better than Class IV for not to be a difficult intubation.

  2. Thyromental distance

    Time frame: 1 minute

    measured from the thyroid notch to the tip of the jaw with the head extended

  3. Sternomental distance

    Time frame: 1 minute

    the distance from the suprasternal notch to the mentum and is measured with the head fully extended on the neck and the mouth closed

  4. Interincisor distance

    Time frame: 1 minute

    DIstance in centimeters between fornt incisors

  5. Upper Lip Bite Test

    Time frame: 1 minute

    upper lip bite criteria-class I = lower incisors can bite the upper lip above the vermilion line, class II = lower incisors can bite the upper lip below the vermilion line, and class III = lower incisors cannot bite the upper lip. Class I is the best for not to be a difficult intubation, class III means it´s posibble a difficult laryngoscopy.

  6. neck circumference

    Time frame: 1 minute

    Using a flexible measuring tape in centimeters, neck circumference at the level of thethyroid cartilage will be measured

Sponsors and collaborators

Lead sponsor

Clinica Universidad de Navarra, Universidad de Navarra

Other

Registry information

Important dates

Study start
2019
Primary completion
2020
Study completion
2020
First posted
Nov 19, 2019
Registry last updated
Mar 16, 2021

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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