ANTICIPATION OF THE DIFFICULT AIRWAY: THE PREOPERATIVE AIRWAY ASSESSMENT FORM AS AN EDUCATIONAL AND QUALITY IMPROVEMENT TOOL Carin Hagberg, M.D. Davide Cattano, M.D., Ph.D. Jon Tyson, M.D. Funding supplied by Research in Education Grant from Foundation of Anesthesia Education and Research (FAER)

Ian Latto and Michael Rosen DIFFICULT AIRWAY MANAGEMENT IS ONE OF THE MOST CHALLENGING TASKS FOR ANESTHESIOLOGISTS Does the Airway Examination Prevent Difficult Intubation ? DMV grossly 1 :1000 D- Laryngoscopy 10 : 100 Difficult Intubation 1 : 100 Difficult SGA management ? Difficult Surgical Airway ? “There is one skill above all else that an anaesthetist is expected to exhibit and that is to maintain the airway impeccably” Ian Latto and Michael Rosen

at a minimum, a preanesthesia physical examination should include (1) an airway exam [100% consultants (72), 100% ASA members (273)]…

The specific respiratory events are depicted here The specific respiratory events are depicted here. Difficult intubation and inadequate ventilation/oxygenation account are the most prevalent and account for almost half of the damaging events. Esophageal intubation and premature extubation were the next most common. Other respiratory events were endobronchial intubation, bronchospasm, and inadvertent extubation. Anesthesia care was judged by the reviewers to be less than appropriate in 64% of the respiratory-related damages,as compared to 28% in the CV event group. Among the respiratory events, care was most often judged to be less than appropriate in claims for esophageal intubation and premature extubation and inadequate ventilation. The aspiration group had the lowest proportion of claims where the care was judged as less than apporpriate.

APSF SURVEY RESULTS IDENTIFY SAFETY ISSUES PRIORITY: AIRWAY STILL #1 Difficult Airway Management Cost-Saving: Production Pressures Anesthesia Delivery: Remote Sites Anesthesia Delivery: Office-Based Neurologic Deficit Due to Anes Tech Coronary Heart Disease (Pts) Occupational Stress Fatigue Medication Errors Cost-Saving: Time for Pre-op Eval In late 1998, the Executive committee of the Anesthesia Patient Safety Foundation conducted a survey designed to identify the most important anesthesia patient safety issues as perceived by practicing anesthesiologists. The survey was administered by mail to 1660 members of the ASA. It was also available at the APSF Booth at the 1998 ASA annual meeting. The top 10 safety issues are shown here and as you can see, DAM was the highest, being marked as high priority by 72% of the 801 respondents. NO WONDER YOU ARE SITTING IN THIS AUDIENCE!!!!Of course, if you are working in a free standing sugery centerr and concerned about production and your patient has CAD, you are really going to be stressed. In late 1998, the Executive Committee of the Anesthesia Patient Safety Foundation (APSF) conducted a survey designed to identify the most important anesthesia patient safety issues as perceived by practicing anesthesiologists. The survey was initially administered by mail to 1660 members of the ASA and it was also available for on-site completion to visitors at the APSF/ASA Patient Safety Booth at the ASA Annual Meeting in Oct, 1998. The 10 most important anesthesia patient safety issues as determined by a “High Priority” ranked by 801 anesthesiologist respondents rated Difficult Airway Management as the most important patient safety issue being ranked by 72%. NO WONDER YOU ARE ALL HERE IN THIS ROOM, HEARING THIS LECTURE. Stoelting RK: APSF Newsletter 1999; 14:6

WHY IS THIS STUDY IMPORTANT? Difficult airway management pertains to every anesthesiologist May reduce stress for both the anesthesiologist and patient May reduce morbidity and mortality May create a universal evaluation system May increase overall knowledge about airway features

STUDY DESIGN – GOALS Primary Hypothesis Use of a specially designed preoperative airway assessment form by anesthesiology residents will result in more complete documentation of important airway features (as designated by the American Society of Anesthesiologists) compared to use of the current forms

STUDY DESIGN – GOALS Secondary Hypotheses: New preoperative form will result in greater resident recognition of patients at high risk for difficult airway as judged independently by senior anesthesiology faculty Greater number of awake intubations by residents using the new form Number of multiple intubation attempts and invasive surgical intubation techniques may decrease with residents using the new form Identify and characterize features of Difficult SGD and Surgical Airway Increased spontaneous knowledge of important airway features by 18 months for residents using the new form Observations during the study will help refine the new form

STUDY DESIGN – PARTICIPANTS All anesthesiology residents between July 2008- June 2010 Locations: MHH LBJ 2 groups Group A Current preoperative assessment Postoperative evaluation Group B New preoperative airway assessment Study faculty will perform independent preoperative airway assessments Dr. Davide Cattano Dr. Carin Hagberg Dr. Sara Guzman

STUDY DESIGN – LOGISTICS Preoperative assessments: Specialized attending and resident will be blind to each other’s assessment Resident should review assessment with their assigned attending Specialized attending will page attending assigned to case when a difficult airway is anticipated Forms must be returned to billing Completeness/accuracy of charting will be assessed

CURRENT PRE-OP ASSESSMENT FORMS

NEW PREOP AIRWAY ASSESSMENT FORM

5 AREAS OF DIFFICULT AIRWAY MANAGEMENT Difficult mask ventilation Difficult supraglottic airway Difficult laryngoscopy Difficult intubation Difficult surgical airway

DIFFICULT MASK VENTILATION PREOPERATIVE RISK FACTORS Condition in which the anesthesiologist cannot provide adequate mask ventilation due to inadequate seal, excessive leak, or resistance to gas flow Mask seal (M) BMI > 26 kg/m2 (O) Age > 55 yrs (A) Lack of teeth (N) History of snoring (S) MOANS Mask seal (beard/moustache) Can use lube or request the patient to shave. Nothing against men with beard or moustache’s, as my husband has them, but sometimes facial hair can hide anatomical abnormalities and you might uncover a DA. Rather than simply remove dentures in the DSU, you could have the patient’s leave them in until you have finished MV, yet remove them prior to intubation. Can’t do much about a patient’s age and weight or whether they wake their spouse up with snoring, but you can get an adequate preop assessment of whether or not they have OSA and what special precautions you need to perform. Langeron O et al: Prediction of Difficult Mask Ventilation. ANESTHESIOLOGY 2000; 92:1229-36

DIFFICULT SUPRAGLOTTIC AIRWAY Result of poor device placement or inability to adequately ventilate with device successfully placed Restricted mouth opening (R) Obstruction of upper airway (O) Distortion/disruption of airway (D) Stiff lungs (reduced compliance or increased resistance) (S) "RODS"

DIFFICULT LARYNGOSCOPY Inability to visualize any portion of the vocal cords after multiple attempts at conventional laryngoscopy Grade 1 Grade 2a Grade 2b Grade 3 Grade 4 Yentis & Lee Modification of Cormack & Lehane Classification

DIFFICULT LARYNGOSCOPY - LEMON Look Externally (L) Evaluate 3-3-2 (E) Mallampati class (M) Obstruction (O) Neck mobility (N) "LEMON" 3. Mouth opening 2. Mental to hyoid 3. Hyoid to thyroid

Patients’ preexisting conditions: Difficult Intubation A Difficult Laryngoscopy does not automatically predict a Difficult Intubation Easy Laryngoscopy but conditions altering the anatomy of the larynx or the trachea Difficult laryngoscopy Requires multiple attempts AlternativeTechniques Difficult Intubations Can Be Skill Related Examples of alternative techniques: 1.FOB- fogging, bleeding 2. I-LMA- mouth opening, tonsils, alignment of axis 3. Glidescope- mouth opening, cannot pass and align the ETT Patients’ preexisting conditions: Severe tracheal deviation Bleeding disorders Neck abscess Laryngeal and subglottic tumor Etc.

DIFFICULT SURGICAL AIRWAY SHORT Surgery/disrupted airway (S) Hematoma/infection (H) Obese/access problems (O) Radiation/excessive bleeding (R) Tumors (T) Mask seal (beard/moustache) Can use lube or request the patient to shave. Nothing against men with beard or moustache’s, as my husband has them, but sometimes facial hair can hide anatomical abnormalities and you might uncover a DA. Rather than simply remove dentures in the DSU, you could have the patient’s leave them in until you have finished MV, yet remove them prior to intubation. Can’t do much about a patient’s age and weight or whether they wake their spouse up with snoring, but you can get an adequate preop assessment of whether or not they have OSA and what special precautions you need to perform. Walls R, Murphy M; National Airway Course, USA

PLAN DESCRIPTION Note how you will proceed on the form What type of anesthesia will you administer? Local or general?

POSTOPERATIVE EVALUATION

MASK VENTILATION Evaluation of mask ventilation

SGA DEVICE Evaluation of supraglottic airway device (if used)

C-L AND INTUBATION Evaluation of Cormack and Lehane grade on DL Evaluation of Intubation (if performed)

SURGICAL EVALUATION Evaluation of surgical airway (if applicable)

EXTUBATION Evaluate extubation Register difficult airway (if applicable)

TO ERR IS HUMAN, TO FORGIVE IS DIVINE Alexander Pope [21 May 1688 – 30 May 1744] english poet Errare humanum est perseverare diabolicum Seneca the Younger or Lucius Anneus Seneca (c. 4 BC – AD 65)