Select Anesthesia Airway Related Emergencies: Management and Evidence Based Prevention Strategies

1. Select Anesthesia Airway Related Emergencies: Management and Evidence Based Prevention Strategies Bill Howie DNP, CRNA University of Maryland Medical Center/Shock Trauma Center Uniformed University of the Health Sciences Catholic University of America 08 March 2014 MANA

2. Objectives • Following this presentation the participant will: • Discuss strategies to prevent adverse patient outcomes when faced with: An unrecognized difficult airway; an acutely injured trauma patient; a patient at risk for aspiration; a patient at risk for an airway fire ; a patient with an airway obstruction; and an unintended endobronchial intubation.

3. ASA Closed Claims 2013

4. ASA Closed Claims 2013: Specific to Airway

5. Airway Misadventures: Unrecognized Difficult Airway • Complications arising from difficult or failed tracheal intubation remain a leading cause of anesthetic morbidity and mortality, despite the advent of recent developments in airway management strategies (Langeron et al. 2006; Malik, et al. 2009; Hagberg 2013)

6. Airway Exam Techniques • Physical exam: mouth opening, teeth (or tooth) configuration? neck mobility , thyromental distance, jaw mobility, tongue size, length of neck, neck scars (old trach, neck surgeries?), evidence of previous radiation therapy or a history of such? • History : no prior radical head and neck surgeries? No history of obstructive sleep apnea (redundant tissue) • Preop exam written by others? Always do your own airway exam on all patients!

7. Airway Exam: Do you do it on all of your patient’s? Every time? ASA Practice Guidelines for management of the difficult airway (2013) Anesthesiology: 118(2) pp 1-20.

8. Airway Exams

9. Airway Exams Berkow, L. What’s new in airway management (2013) ASA Refresher Course: 41(1) pp 31-37.

10. Airway Exams • Berkow, L. What’s new in airway management (2013) ASA • Refresher Course: 41(1) pp 31-37

11. Airway Exams

12. Airway Exams

13. The Unrecognized Difficult Airway • It has been defined as the clinical situation in which a conventionally trained anesthetist experiences difficulty with face mask ventilation , difficulty with tracheal intubation, or both ( ASA 2003) • Much study has been conducted to identify strategies to deal with this significant anesthesia and critical care problem (Airway examination techniques , airway adjuncts, airway rescue devices, airway practice simulators, emergency surgical airways, difficult airway workshops and the like)

14. Prediction and outcomes of impossible mask ventilation • An observational study of 94,630 anesthetics performed 2004 to 2008 was completed • 53,041 operations included an attempt at mask ventilation. 77 patients (0.15%) were noted to be impossible to ventilate (incidence of 1: 690) • 19 (25%) of the patients were noted to be a difficult intubation • 15 of these were intubated • 4 were not (2 surgical airways and 2 were awakened and a fiberoptic was done)

15. Prediction and outcomes of impossible mask ventilation • Factors linked to the difficulties were: • Neck radiation changes (the most significant clinical predictor in this review) • Male sex • Sleep apnea • Mallampati III or IV • Presence of a beard Kheterpal S., et al. (2009) Prediction and outcomes of impossible mask ventialtion. Anesthesiology 110(4): pp 891-897.

16. Difficult and failed intubation in 3430 OB General Anesthetics • The most frequent cause of maternal death in the UK was failed intubation (50 of 103 reported deaths from 1976-2005) • The authors collected data from 2000-2007 and reported a total of 55,057 deliveries • Difficult intubation was reported in 23 of 3430 patients (1:156 patients) • 14 cases (61%) were unanticipated difficult intubations

17. Difficult and failed intubation in 3430 OB General Anesthetics • Risk factors to explain the unrecognized difficult intubation were noted to be due to an inadequate preop assessment: • no recorded assessment (6 cases) • poorly documented airway exam(8 cases) • 7 patients were overweight • 2 of the patients had a BMI > 35 All patients were successfully intubated primarily with a bougie The authors noted that the low rate of general anesthetic in OB does not allow providers adequate experience in airway management. And, a thorough airway exam is essential to provide a safe anesthetic Djabatey EA., & Barclay PM. (2009) Difficult of failed intubation in 3430 general anesthetics. Anaesthesia 64(11) pp 1168-1171

18. Airway Misadventures: Unrecognized Difficult Airway (Prevention) • When applied in accordance with a predefined algorithm, the gum elastic bougie and the ILMA™ are effective to solve most problems occurring during unexpected difficult airway management (Combes et al. 2004) • Other studies have noted potential improved success using alternative adjuncts (Bullard , retrograde wire, LMA Ctrach, Airtraq Laryngoscope, LMA-Fastrach, and the Glidescope) (Rich 2005; Malik et al 2009)

19. An Algorithm for Difficult Airway Management, Modified for Modern Optical Devices (Airtraq Laryngoscope; LMA Ctrach) A 2-Year Prospective Validation in Patients for Elective Abdominal , Gynecological, and Thyroid Surgery. Amathieu, et al. Anesthesiology 2011; 114:25–33. An algorithm for airway management that incorporates Gum Elastic Bougie (GEB), LMA-CT, and AQ-L devices was used in 12,225 anesthetized, paralyzed patients. Successful tracheal intubation under visual control was achieved in all patients with difficult airways.

20. Airway Misadventures: Unrecognized Difficult Airway (Prevention) • The PentaxAWSw laryngoscope demonstrated more advantages over the Macintosh laryngoscope than either the Truview EVO2w or the Glidescope w laryngoscope, when used by experienced anaesthetists in difficult tracheal intubation scenarios (Malik et al 2009) • Who in the audience has ever faced an unrecognized difficult airway? • What strategy worked the best for you?

21. ASA Airway Algorithm

22. 2013 ASA Difficult Airway Algorithm

23. ASA Airway Algorithm in Trauma • When faced with the acutely injured trauma patient the provider must have: • All necessary airway and anesthesia equipment immediately available and checked for function • An understanding of the basic “rules of trauma” (full stomach, potentially hypovolemic, potentially closed head injured, potentially c-spine injured, potentially premedicated, etc) • Enough help immediately available to handle the airway (how many people do you need?) • A clear plan regarding management of the airway (Bailitz et al 2011)

25. The Success of Emergency Endotracheal Intubation inTrauma Patients: A 10-Year Experience at a Major AdultTrauma Referral Center • 6088 patients admitted to the STC required intubation within the first hour, 21(0.3%) received a surgical airway. During the first 24 h, 10 more patients (n=31), received a surgical airway, during approximately 32,000 attempts (0.1%). Unanticipated difficult upper airway anatomy was the leading reason for a surgical airway. Four of the 31 patients died of their injuries but none as the result of failed intubation. (Stephens et al: 2009)

26. Shock Trauma Center Rapid Sequence Inductions (Stephens et al: 2009)

27. The Success of Emergency Endotracheal Intubation inTrauma Patients: A 10-Year Experience at a Major Adult Trauma Referral Center • Rapid sequence induction followed by direct laryngoscopy is a remarkably effective approach to emergency airway management. An algorithm designed around this approach can achieve very high levels of success (Stephens et al: 2009)

28. Trauma Airway AlgorithmStephens et al: 2009

29. Trauma Airway Algorithm

30. Airway Misadventures: Unrecognized Difficult Airway (If it becomes difficult to ventilate as you struggle to intubate) • Difficult mask ventilation: presents as the inability to provide adequate face mask ventilation due to inadequate mask seal, excessive gas leak, or excessive resistance to gas flow • There are five independent predictors for difficult mask ventilation: age > 55, BMI > 26, presence of a beard, edentulous , and a history of snoring (Bhavani et al, 2011)

31. Airway Misadventures: Unrecognized Difficult Airway • The inability to adequately ventilate your patient makes this a true life threatening emergency • Uniform application of a difficult airway algorithm might decrease the incidence of hypoxic brain damage during anesthesia induction (Amathieu 2011) • Uniform application of a clear algorithm might decrease patient injury or death in any situation where airway management turns difficult

32. Airway Misadventures: Unrecognized Difficult Airway • Experience in surgical airway techniques is essential (cricothyroidotomy). Training in such techniques is mandatory for any organization with a safety culture. These techniques should be practiced in workshops and their daily use in certain ENT and trauma situations is good practice that provides further experience (Heidegger et al. 2005) • Your facility should have a mechanism to deal with a failed airway scenario (emergency surgical airway team? Or just the closest podiatric surgeon?)

33. Unrecognized Difficult Airway: Lessons Learned • Difficult airway cases brought to lawsuit were reviewed in the ASA Closed Claims Data Base (n=179 from 1985-1999) • The analysis found that the difficult airway sentinel events occurred : 67% upon induction, 15% during surgery, 12% at extubation, and 5% during recovery (Peterson et al. ASA 2005)

34. Airway Misadventures: Unrecognized Difficult Airway (Lessons Learned) • Persistent attempts to instrument the airway with the same unsuccessful technique waste valuable time • A preset difficult airway algorithm is critical. Do you have the necessary equipment on hand, and are you comfortable using it? • Call for help early. (The airline industry has pointed to countless crashes attributed to failure of crew members to speak-up and note a problem. Lack of a “safety culture”) (Bhavani et al 2011)

35. Anesthesia Emergencies • Rapid Sequence Induction: A technique of inducing general anesthesia to quickly secure the airway to reduce the risk of pulmonary aspiration of gastric contents • Indications: Emergency surgery/non-fasting patients/acute abdomen/paralytic ileus/ reflux/obesity/diabetes/pregnancy • Airway management is the most important skill for an emergency practitioner to master because failure to secure an adequate airway can quickly lead to death or disability

36. Rapid Sequence Induction • Contraindications: Patients with anticipated difficult airway • Situations where laryngeal injury suspected • Which muscle relaxant should be used? (Sux, Roc, Vec, Cisatracurium- or does it matter?) • Roc vsSux for RSI: Cochrane Review found Sux created superior intubating conditions (perceived as excellent. But when less stringent clinically acceptable conditions used, there were not statistically significant differences found when propofol was used to induce (Perry et al 2008)

37. RSI: Best Practice

38. Rapid Sequence Induction

39. Rapid Sequence Induction • Rapid Sequence Induction includes specific separate actions to reduce risk of pulmonary aspiration: • Administration of a rapid acting IV induction agent and muscle relaxant simultaneously (classic RSI) • No mask ventilation (classic versus modified?) • Cricoid pressure • Smooth and skillful laryngoscopy (trainees?) • Provision of optimal pre-oxygenation clearly is recommended whenever possible.

40. Rapid Sequence Induction The standard of care in emergency airway management for intubations not considered to be difficult • It is key that the provider remembers : • Prepare (assess the airway/have primary and backup equipment assembled) • Preoxygenate • Paralysis and induction drugs at the same time • Protection (cricoid) (zantac/reglan/bicitra ?)and positioning (head up or head slightly down?) • Placement of cuffed ETT with proof of ETC02 • Post-intubation management (sedation/vent)

41. Complications of Intubation

42. Rapid Sequence InductionOut-of-hospital airway management in the United States. Wang et al 2011 The 2008 National Emergency Medical Services Information System (NEMSIS) Public-Release Data Set containing data from 16 states was utilized • Among 4,383,768 EMS activations, there were 10,356 Endotrachial Intubations, 2246 alternate airways, and 88 cricothyroidotomies. ETI success rates were: overall 6482/8418 (77.0%) • Alternate airway success was 1564/1794 (87.2%). Major complications included: bleeding 84 (7.0 per 1000 interventions), vomiting 80 (6.7 per 1000) and esophageal intubation 12 (1.0 per 1000)

43. PREHOSPITAL MANAGEMENT OF THE DIFFICULT AIRWAY: A PROSPECTIVE COHORT STUDY (Warner et al. 2009) • Data were collected prospectively for all ETIs performed by the fire department from 2001–2005, and included demographics, number of laryngoscopy attempts, airway procedures, complications, and outcomes • Of 80,501 ALS patient contacts, 4091 (5.1%) underwent attempted oral ETI, with a 96.8% success rate in four or fewer attempts

44. Prehospital Airway: Lessons Learned • The difficult airway cohort included 130 patients (3.2%), whose airway management consisted of oral ETI after more than four attempts (46%), bag-valve-mask ventilation (33%), cricothyroidotomy (8%), retrograde ETI (5%), and digital ETI (1%) • Procedural success rates ranged from 14% (digital ETI) to 91% (cricothyroidotomy). Nine patients (7%) had failed airway management, of whom 5 were found in cardiac arrest

45. Prehospital Airway: Lessons Learned • The two most common reasons reported by ALS providers for airway difficulty were anterior trachea (39%) and small mouth (30%). Overall mortality for the difficult airway cohort was 44% • Patient anatomy was a primary factor in failed ETI • Among the advanced procedures utilized, cricothyroidotomy had the highest success rate and should not be delayed by other interventions

46. Evidence-Based Clinical Update on Aspiration and Rapid Sequence Induction • A systematic review was done (184 clinical trials) The overall conclusion was that: • There was an absence of evidence to either support or discourage the use of the RSI technique for the prevention of aspiration • The use of a modified RSI that permits ventilation with cricoid after induction may be appropriate in some situations

47. Evidence-Based Clinical Update on Aspiration and Rapid Sequence Induction • Available studies support use of sux due to its speed of offset since it gives the fastest and best early intubation conditions (less coughing with early instrumentation) (Sluga et al 2005). However, higher dose Roc or Vec provide clinically similar results to sux • Controlled trials are necessary to provide more evidence to strongly recommend the RSI technique. (Which drugs are best? (Etomidatevs STP vsPropofolvsKetamine; FentanylvsLidocaine to blunt laryngoscopy stimulation) Bag valve mask ventilation while waiting for agents to take effect? • (Neilipovitz et al 2007)

48. Airway Emergencies: Aspiration • Aspiration: Inhalation of material into the airway below the level of the true vocal cords • The incidence of aspiration in adults is: • 1 in 3000 anesthetics • 1 in 600-800 emergency surgeries • 1 in 400-900 C-sections under general anesthesia • 1 in 2600 for children • 1 in 400 or emergency surgery in children

49. Aspiration in the Perioperative Period • Risk Factors: Trauma/Emergency surgeries, gastroparesis (multiple causes), head injured /CVA patients (altered gag/swallow/LOC), GERD, Obesity, Pregnancy, obstruction, lied about PO intake preoperatively, extremes of age, impaired LOC due to illicit drugs and or ETOH, lithotomy and occurrence of a difficult intubation/difficult airway (Kalinowski 2004; Sekar et al 2011)

50. Airway Emergencies: Aspiration • The consequences of aspiration can lead to situations where patients need > 48 hours of ventilator/ICU support • Acute lung injury associated with aspiration produces impaired arterial oxygenation with a Pa02/Fi02 ratio of < 300 • Extreme lung injury may progress to ARDS and a Pa02/Fi02 ratio of < 200 • There is a 50% mortality • (Kalinowski & Kirsch 2004)