Ultrasound Airway Assessment of Critically Ill Preeclamptic; Comparison Between Two Technique

Official title

the Preoperative Use of Ultrasound in Airway Assessment in Critically Ill Obstetrics With Pre-eclampsia; Comparison Between Two Ultrasound Techniques in Relation to the Standard Clinical Assessment

Overview

Unexpected difficult airway exposes the patient to serious morbidity and even mortality. The changes in pregnancy and preeclampsia increase the risk of difficult intubation. Proper anticipation affects the outcome and enhances safety, especially in critically ill patients. This research aims to assess the superiority of either 2 views or 5 views ultrasound assessment in predictivity of difficult airway (difficult ventilation, laryngoscopy, and intubation) and their comparison to traditional clinical examination by El-Ganzouri Risk Index (EGRI) in critically ill obstetric patients with pre-eclampsia.

Detailed description

Unexpected difficult airway exposes the patient to serious morbidity and even mortality. Obstetrics airway carries the risk of complications due to physiological changes. The airway shows more restriction and changes in preeclamptic patients and peripartum periods. A study reported one incidence of difficult intubation in obstetrics in 20 cases. Inadequate airway management leads to failure in ventilation and oxygenation of the critically ill mother and her fetus.

the Practice Guidelines for Management of the Difficult Airway by the American Society of Anesthesiologists (ASA) define the difficult airway as difficult facemask ventilation of the upper airway, difficult tracheal intubation, or both. preoperative assessment of the airway avoids that risk; however, current clinical screening tests have low sensitivity and specificity with limited predictivity.

Ultrasound (US) provides a more precise assessment for tissues like epiglottis, vocal cords, and ring-shaped membranes; thus, it facilitates a bedside, non-invasive objective airway assessment. Moreover, ultrasound assessment can plan and guide airway interventions if needed. The airway in pregnancy goes through changes. a study concluded that The US airway assessment parameters differ significantly between pregnant and non-pregnant patients. Previous studies reported that the best predictors of difficult laryngoscopy and/or difficult intubation were the epiglottis midline-skin distance, hyoid bone-to-skin distance, thyroid cartilage-to-skin distance, thyrohyoid membrane-to-skin distance, and vocal cord anterior commissure-skin distance also predicted difficult airway. In Pregnancy, hyoid bone visibility, and Pre-E/E-VC ratio were independent predictors of the difficult airway.

Researchers suggested different techniques for airway ultrasound. Some suggested detailed technique that allows the determination of multiple parameters. Others suggested a more concise protocol to lessen the time of assessment and to avoid complexity.

This trial assesses the superiority of either 2 views or 5 views ultrasound assessment in predictivity of difficult airway (difficult ventilation, laryngoscopy, and intubation) and their comparison to traditional clinical examination by El-Ganzouri index (GREI) (9) in critically ill obstetric patients with pre-eclampsia.

Interventions

• Diagnostic test techniques of ultrasound examination of the airway
  two different techniques of ultrasound. The techniques are the two views and the five views

Primary outcome measures

• The predictivity of both us techniques in relation to clinical assessment of El-Ganzouri index (EGRI). [Time frame: the degree of difficult intubation will be assesed intraoperative after aneesthesia and intubation, clinical assessment will be preoperative, the us assessment will be preoperative at the same day of operation or immediately postoperative]
• The predictive superiority between 2 view and 5 views ultrasound techniques regarding difficult ventilation, laryngoscopy and intubation [Time frame: the actual degree of difficult intubation will be assesed intraoperative after aneesthesia and intubation, the us assessment will be done preoperative at the same day of operation or immediately postoperative]

Secondary outcome measures (2)

• postoperative side effects [Time frame: within 24 hours postoperative]
• duration of the airway assessment [Time frame: preoperative]

Eligibility criteria

Inclusion Criteria:Critically ill preeclamptic patients for caesarean section under general anesthesia with the following criteria:

• Aged from 18 to 60 years.
• Singleton or multiple pregnancies,
• Mentally competent.
• American Society of Anesthesiologists (ASA) physical status I, II and III

Exclusion criteria

• Patient's Refusal to participate,
• Abnormal pharynx or airway anatomy,
• expected difficult laryngoscopy with cervical spine abnormality,
• Maxillofacial anomalies,
• upper airway diseases or malignancy,
• Unconscious women,
• those with learning difficulties, or mentally handicapped

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Diagnostic

Study locations

Egypt · 1 center

• Ain shams university — Cairo

Publications

• Bala R, Budhwar D, Kumar V, Singhal S, Kaushik P, Sharma J. Clinical and ultrasonographic assessment of airway indices among non-pregnant, normotensive pregnant and pre-eclamptic patients: a prospective observational study. Int J Obstet Anesth. 2023 May;54:103637. doi: 10.1016/j.ijoa.2023.103637. Epub 2023 Feb 1. PMID 36827944
• Gomes SH, Simoes AM, Nunes AM, Pereira MV, Teoh WH, Costa PS, Kristensen MS, Teixeira PM, Pego JM. Useful Ultrasonographic Parameters to Predict Difficult Laryngoscopy and Difficult Tracheal Intubation-A Systematic Review and Meta-Analysis. Front Med (Lausanne). 2021 May 28;8:671658. doi: 10.3389/fmed.2021.671658. eCollection 2021. PMID 34124099
• Zheng BX, Zheng H, Lin XM. Ultrasound for predicting difficult airway in obstetric anesthesia: Protocol and methods for a prospective observational clinical study. Medicine (Baltimore). 2019 Nov;98(46):e17846. doi: 10.1097/MD.0000000000017846. PMID 31725624
• Izci B, Riha RL, Martin SE, Vennelle M, Liston WA, Dundas KC, Calder AA, Douglas NJ. The upper airway in pregnancy and pre-eclampsia. Am J Respir Crit Care Med. 2003 Jan 15;167(2):137-40. doi: 10.1164/rccm.200206-590OC. Epub 2002 Oct 31. PMID 12411285

Identifiers

NCT: NCT06651879 · FMASU R147/2024

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗