Embed Size (px)
Citation preview
Topics in Airway Management:Intelligent Airway Evaluation
Donald M. Voltz, MDAssistant Professor of Anesthesiology
Case Western Reserve University / University Hospitals of Cleveland
3 November 2004
What we focus on and our mental models determine what
we see.
What is Intelligence?
Turing Test
Intelligence = Prediction
Is There Such a Thing as an Unexpected Difficult Intubation?
What is the Problem?
“More than 85% of respiratory-related closed claims involve a
brain-damaged or dead patient.”
Jonathan Benumof, MD
Incidence of Difficult Intubation
• Successful with multiple attempts
• Successful, many attempts, many people
• Unsuccessful• Can not ventilate or
intubate
• 100-1800/10,000
(1-18%)• 100-400/10,000
(1-4%)• 5-35/10,000
(0.05-.35%)• 0.01-2/10,000
(0.0001-0.02%)
What do we want to Predict?
Cormack-Lehane Classifications
Airway Prediction Models
Airway Prediction Models
• Mallenpatti Classification
• Neck Range of Motion
• Thyromental/Thyrosternal Distance
• Upper Lip Bite Test
• Multivariate Analysis
Mallinpatti Classification
Mallinpatti Classification
Upper Lip Bite Test
Upper Lip Bite TestTable 1. Relationship Between the Results of Two Predicting Tests and Laryngoscopy Grades in 300 Patients
I and II III and IV Predicting test
Modified Mallampati
Classes I and II 189 3
Classes III and IV 94 14
Upper lip bite
Classes I and II 251 4
Class III 32 13
Laryngoscopic view
ASA Difficult Airway ASA Difficult Airway AlgorithmAlgorithm
Updated 2003Updated 2003
Airway Evaluation
Mouth (4)
Oral Cavity (3)
Neck (4)
Airway Evaluation - Mouth
• Length of Upper Incisors
• Relationship of Maxillary Incisors to Mandibular Incisors
• Ability to Prognath the Mandible
• Interincisor Distance
Airway Evaluation – Oral Cavity
• Visibility of the Uvula
• Shape of the Palate
• Compliance of the Mandibular Space
Airway Evaluation - Neck
• Thyromental/Thyrosternal Distance
• Length of the Neck
• Thickness of the Neck
• Range of Motion of the Head and Neck
Approaching the Difficult Airway Algorithm
William H. Rosenblatt, M.D.
Yale University School of Medicine
Is Airway Management Required?
Do you predict difficult direct laryngoscopy?
Will superlarngeal ventilation be possible?
Predictors of Difficult Mask Ventilation
• Age greater than 55 years
• Body mass index greater than 26 kg/m2
• History of snoring
• Edentulous
• Presence of facial hair
Is the patient at an increased risk of aspiration?
Will the patient tolerate a judgment error?
Problems with Prediction Methods
Future of Airway Prediction
References
• Rosenblatt, W.H. Decision making in airway evaluation. ASA Refresher Course in Anesthesiology, V. 32, 2004.
• Benumof, J.L. Airway Management, pp. 121-158, 1996.
• ASA Task Force on Airway Management. Practice Guidelines for Management of the Difficult Airway: An Updated Report by the American Society of Anesthesiologists Task Force on Management of the Difficult Airway, Anesthesiology, 98(5), 1269-1277.
