Más contenido relacionado


  1. NBCRNA Core Modules Supplemental Part 2 Airway Management Instrumentation & Techniques Amy Sheppard, CRNA, MSNA
  2. Getting your credits ❖ NBCRNA Core Module #1: Airway ❖ Series of 3 Airway lectures online: INCLUDED in conference fee ❖ CRNA Today is a recognized vendor for NBCRNA & Prior Approve by the AANA
  3. Getting your credits ❖ FIRST – Visit and Register at CRNAToday.com ❖ Enroll in the Airway: NBCRNA Core Module #1….At check out utilize your Coupon Code “1FL” followed by your AANA number. NO Leading zero. Click Update ❖ Online lecture ❖ Can be viewed on-demand…. ❖ 3 attempts to pass Post Test ❖ To get Class A Credit- A Post Test grade of 80% is required ❖ 3 Attempts ❖ Certificate is only available after passing ❖ All records submitted to the AANA monthly
  4. Objectives ❖ The Learner will demonstrate the appropriate steps in assessing an airway to develop the appropriate patient-specific plan that ensures safe management of the airway and facilitates continuity of care ❖ The Learner will identify the indications and contraindications associated with the use of airway equipment. ❖ The Learner will understand the associated malpractice claims arising from the management of the airway, using a closed claims analysis. ❖ The Learner will identify the complications associated with airway equipment
  5. History of Airway Management Morton Inhaler Dräger “Pulmonator” Alfred Kirstein Autoscope 1943 1941 Murphy Endotracheal Tube “Airway Management” A broad term used to describe the tools, techniques and procedures used to support and control oxygenation and ventilation as well as delivery of anesthetics.
  6. Getting started ❖ What factors need to be considered? • NPO status • Risk of aspiration • Patient factors • Surgeon factors • Type and length of surgery • Regional anesthesia • Provider competencies
  7. Preoperative Fasting Guidelines ❖ 2017: ASA updated recommendations for pre-operative fasting1 • 2 hours clear liquids • 4 hours breast milk • 6 hours solid foods, infant formula & non-human milk • 8 hours fried or fatty foods
  8. Preoperative Fasting Guidelines ❖ Gum, smokeless tobacco, hard candy2 • Not specifically addressed by the ASA guidelines • European Society of Anaesthesiology guidelines do NOT recommend delaying anesthesia
  9. Aspiration Prophylaxis ❖ Overall incidence of aspiration remains very low ❖ Incidence of anesthesia related fatal aspiration was only 1:350,000 (.0003%)3 ❖ In the NAP4 study, aspiration was responsible for 50% anesthetic deaths.3 ❖ Risk of aspiration is greater with higher patient Physical Status (ASA status) and emergency surgery3
  10. Aspiration Prophylaxis ❖ The intended goal of aspiration prophylaxis is to decrease gastric volume and pH. ❖ Sodium Citrate, Metoclopramide, Ranitidine (or other H2 antagonist) The ASA guidelines do NOT recommend routine prophylaxis1
  11. Aspiration Prophylaxis ❖ Full stomach ❖ Diabetic gastroparesis ❖ Symptomatic GERD ❖ Pregnancy ❖ Emergency surgery ❖ ESRD ❖ GI obstruction ❖ Hiatal hernia ❖ Active N/V ❖ NG tube ❖ Morbid obesity Indications: 4, 5
  12. Aspiration Prophylaxis in Pregnancy Updated report from ASA task force on Obstetric Anesthesia & the Society for Obstetric Anesthesia and Perinatology6 For clear liquids: “The uncomplicated patient undergoing elective surgery (e.g. scheduled C/S, post partum tubal ligation) may have moderate amounts of clear liquids before induction of anesthesia.” For solids: “The patient undergoing elective surgery (e.g. scheduled C/S, post partum tubal ligation) should undergo a fasting period of 6-8 hours depending on the type of food ingested (e.g. fat content).” Before surgical procedures (e.g., cesarean delivery or post- partum tubal ligation) “The clinician should consider the timely administration of nonparticulate antacids, H2 antagonists, and/or metoclopramide for aspiration prophylaxis.” After 20 weeks gestation, extra caution should be exercised with the unprotected airway to prevent aspiration29
  13. Aspiration Prophylaxis Strategies for reducing aspiration risk3 Reducing gastric volume Preoperative fasting, nasogastric aspiration, pro kinetic premedication Avoidance of general anesthesia Is regional anesthesia an option? Reducing pH of gastric contents Antacids, H2 antagonists, proton pump inhibitors Airway protection Tracheal intubation, 2nd generation supra-glottic airway devices Prevent regurgitation Rapid sequence induction Extubation Extubate only after awake and airway reflexes have returned
  14. Cricoid Pressure & Preventing Aspiration Is it time to LET GO of cricoid pressure?
  15. Cricoid Pressure & Preventing Aspiration ❖ Does cricoid pressure (CP) reduce the risk of aspiration? • Evidence to support that CP is effective is based almost exclusively on cadaver studies and case reports of regurgitation occurring after CP has been released. There is no evidence for or against the use of CP and there are no published randomized controlled trials comparing the incident of regurgitation on induction, with or without the use of CP. Additionally, CP has been shown to decrease LES tone thus potentially increasing the risk of aspiration.3 ❖ Is cricoid pressure properly applied? • Who is applying the CP? Have they been trained? Do YOU even know how to properly apply? ❖ Does properly applied cricoid pressure actually compress the esophagus? • The esophagus is laterally displaced relative to the midline of the vertebral body in 49%-53% of subjects without cricoid pressure being applied. When CP was applied, lateral displacement increased by 53%- 91%.7 ❖ Does cricoid pressure increase or decrease the quality of the laryngeal view? • Numerous articles have been published with contradictory results. However, it has been found that application of > 40N of force can compromise airway patency and cause difficulty with tracheal intubation.7 ❖ Is CP harmful? • Difficult laryngoscopy, esophageal rupture, cricoid fracture8 ❖ Are there any contraindications to use of CP? • Trauma to anterior neck, unstable C-spine, obstructing mass, active vomiting8
  16. Cricoid Pressure & Preventing Aspiration Is it time to LET GO of cricoid pressure? Cochrane Anaesthesia, Critical and Emergency Care Group9 There is currently NO information available from published RCTs (randomized controlled trials) on clinically relevant outcome measures with respect to the application of cricoid pressure during RSI.
  17. Cricoid Pressure & Preventing Aspiration To correctly apply cricoid pressure, 30 - 40N (3 - 4 Kg) of force should be applied downward onto the cricoid cartilage.10 If you are going to do it, you should at least do it correctly.
  18. Just how good is your cricoid? Investigator Ok, please proceed with the application of cricoid pressure to the test fixture
  19. Just how good is your cricoid? Participant OK!
  20. Just how good is your cricoid? Investigator Are you applying cricoid pressure to the test fixture?
  21. Just how good is your cricoid? Participant Yes, of course
  22. Just how good is your cricoid? Investigator Something must be wrong. We’re not registering any pressure? You are pressing down on the cricoid, right?
  23. Just how good is your cricoid? Participant Oh no, I would never do that. I always “squeeze” the sides of the throat. Pushing down would obstruct the view of the person intubating.
  24. Just how good is your cricoid? Investigator And how long have you been applying cricoid pressure in this manner?
  25. Just how good is your cricoid? Participant For 38 years!
  26. Airway Assessment
  27. Airway Assessment No single test has been devised that can predict a difficult airway 100% of the time; especially when tests are done by themselves. Evaluating the Airway
  28. Modified Mallampati Classification • Originally described in 1983, Mallampati is an easy to perform, commonly used airway assessment tool. As a stand alone tool however, it is insufficient to predict the difficult airway.11 • In a meta analysis of over 177,000 patients, only 35% of patients with a difficult intubation were identified as Mallampati III or IV.11 • May be useful clinically when used in combination with other airway predictors11 • To properly perform, the neck should be neutral (not extended) and the patient should not phonate4
  29. LEMON Test15 Evaluation Look externally Are there any physical attributes that stand out? Evaluate 3-3-2 3-3-2 rule Mallampati Obstruction/Obesity Facial trauma, edema, foreign body, obesity, large breasts? Neck mobility RA? Radiation? Burns? *Adapted with permission from The Difficult Airway Site (TheAirwaySite.com) & Walls RM & Murphy, MF:Manual of Emergency Airway Management, 4th ed Philadelphia, Lippincott, Williams and Wilkins, 2012
  30. El-Ganzouri Multivariate Risk Index Abdel Raouf Sayed Ahmed El-Ganzouri, M.D. Test 12, 13 Score Mouth Opening 0 - 1 Mallampati 0 - 2 TM Distance 0 - 2 Neck Movement 0 - 2 Hx difficult intubation 0 - 2 Ability to prognath 0 - 1 Weight 0 - 2 TOTAL 0 - 12 A score ≥ 4 indicates potential difficulty when performing direct laryngoscopy
  31. Documenting EGRI A score ≥ 4 indicates potential difficulty when performing direct laryngoscopy 0 1 2 Mouth Opening ≥ 4 cm < 4 cm Mallampati 1 2 3, 4 TM Distance > 6.5 cm 6 - 6.5 cm < 6 cm Neck Movement > 90 80 - 90 < 80 Hx difficult intubation No Questionable Yes Ability to prognath Yes No Weight < 90 kg 90 - 110 kg > 110 kg Total =_______
  32. Deciding How to Manage the Airway vs vs vs vs vs
  33. Positioning 7-9cm “Sniffing Position”: Neck flexion and head extension14
  34. Positioning Ideally, the external auditory meatus should be in horizontal alignment with the sternal notch. Positioning of the obese patient14
  35. Capnography ❖ Continuously monitor ETC02 during controlled or assisted ventilation and any anesthesia or sedation technique requiring artificial airway support. During moderate or deep sedation, continuously monitor for the presence of expired C02.16
  36. Preoxygenation ❖ Optimal is 3 mins Vt, but 8 Vc may be acceptable.4 ❖ ET O2 should be > 90% to maximize apnea time.4 ❖ What’s the purpose? Denitrogenation: increase the time a patients will stay oxygenated during apnea
  37. Mask Ventilation ❖ Indications: preoxygenation, short duration anesthetic, bridge to definitive airway4 ❖ Relative contraindication: full stomach, facial trauma, unstable c- spine4 ❖ Complications: hyper/hypo ventilation, aspiration4 Ideally, peak inspiratory pressure should be kept less than 20cm H2O4
  38. Prediction of Difficult Mask Ventilation *Adapted with permission from The Difficult Airway Site (TheAirwaySite.com) & Walls RM & Murphy, MF:Manual of Emergency Airway Management, 4th ed Philadelphia, Lippincott, Williams and Wilkins, 2012 MOANS15 Difficult Mask Ventilation Mnemonic Mask Seal Beard? Jowls? Obese Age > 55 y/o No Teeth Is the patient edentulous Stiff/Snoring Stiff neck/jaw? Sleep apnea?
  39. Oral & Nasal Airways Oral4 Nasal4 ❖ Indications: airway obstruction, facilitate mask ventilation, facilitate suctioning ❖ Relative contraindication: intact gag reflex ❖ Complications: dental damage, soft tissue damage, bleeding, lingual nerve palsy ❖ Proper sizing: Corner of mouth to earlobe ❖ Indications: airway obstruction, facilitate mask ventilation, facilitate suctioning ❖ Relative contraindication: basilar skull fracture, coagulopathy ❖ Complications: bleeding, soft tissue damage ❖ Proper sizing: Nostril to earlobe
  40. Supraglottic Airway ❖ Indication: facilitate oxygenation and ventilation, delivery of anesthesia, conduit to intubation, bridge to extubation, failed intubation (rescue device)17 ❖ Relative Contraindications: Active GERD, obesity, traumatic airway injury, intestinal obstruction, intoxication, restricted mouth opening, deformed airway anatomy17 ❖ Complications: Inadequate ventilation, airway injury, sore throat, tongue edema, frenulum injury, aspiration17 Cuff pressure should be <60 cm H2O18
  41. Supraglottic Airways (SGA) ❖ 1st generation: LMA Classic and other manufacturers of laryngeal masks19 • Simple, low pressure • Easy to place ❖ 2nd generation: i-gel, LMA ProSeal, LMA Supreme19 • Additional design features to reduce aspiration risk, allow for higher seal pressure to facilitate controlled ventilation, and may also have integrated bite block.
  42. Prediction of Difficult SGA Placement RODS15 Difficult SGA Placement Mnemonic Restricted Mouth opening Obstruction Distorted Airway Stiff lungs/neck *Adapted with permission from The Difficult Airway Site (TheAirwaySite.com) & Walls RM & Murphy, MF:Manual of Emergency Airway Management, 4th ed Philadelphia, Lippincott, Williams and Wilkins, 2012
  43. LMA in the Prone Patient ❖ Review prone LMA insertion in 441 subjects in 1 RCT, 2 description studies, 1 case series and 2 case reports20 ❖ Successful LMA placement: 100% ❖ Successful ventilation: 100% ❖ Risks: “Comparable to those when LMA’s are used in the supine patient.”
  44. Endotracheal Intubation ❖ Indications: General anesthesia, aspiration prevention, respiratory failure, inadequate oxygenation/ventilation4 ❖ Contraindications: Penetrating or blunt force trauma to the upper airway anatomy, unstable c-spine4 ❖ Complications: Sore throat, dental damage, soft tissue damage, vocal cord damage4
  45. Modified Cormack-Lehane ❖ The Cormack-Lehane classification, first described in 1984, is broadly used to describe the laryngeal view obtained during laryngoscopy4 ❖ 4Yentis further defined this grading system in 1998 when he divided Grade 2 into 2A and 2B4
  46. Direct Laryngoscopy The goal of traditional direct laryngoscopy is to obtain direct line of sight with the glottic opening. To accomplish this task, the rigid laryngoscope is used to align the oral, pharyngeal and laryngeal axes. In the overall patient population, clinicians are unable to visualize the vocal cords when performing direct laryngoscopy up to 7.5% of patients21
  47. Video Laryngoscopy
  48. Predictors of Difficult Video Laryngoscopy ❖ Usual clinical indicators of difficult direct laryngoscopy & intubation do not appear to predict difficult video laryngoscopy.22 ❖ In a study of 6,278 subjects, patients were divided into 2 groups base on their EGRI score21 • ≥ 7 and patient received awake FOB • ≤ 6 and patients were intubated via video laryngoscope ❖ 6 patients received awake FOB based on protocol, 1 patients received awake FOB based on presence of large neck tumor and another an awake tracheostomy for the same reason (even though their score was less than 7). All other patient were intubated via video laryngoscope. ❖ The incidence of C/L grade III was only 0.14% when performing VL. Grade IV was not encountered. All patients in the study were successfully intubated.
  49. Regional anesthesia and the difficult airway ❖ Regional anesthesia is recommended in patients with potentially difficult airways who present for surgery23 ❖ However incidents may occur after the initiation of regional anesthesia that would “force” the clinician to manage the airway. These incidents may include hemorrhage, high/total spinal, anaphylaxis, failed block23 ❖ A successful regional anesthetic may help avoid the need to directly manage a difficult airway, it does not prevent it23 Even when utilizing regional anesthesia, an airway management strategy should always be discussed with the patient and planned in advance23
  50. Apneic Oxygenation ❖ 15 L/min ❖ May prolong the time patient maintain adequate oxygen saturation during laryngoscopy/intubation Use of high-flow nasal cannula oxygen therapy can prevent desaturation during tracheal intubation24
  51. ETT Cuff Pressure ❖ Complications associated with excessive ETT cuff pressure can include25 • Sore throat • Recurrent laryngeal nerve palsy • Mucosal ischemia • Tracheal ulceration • Tracheal stenosis • Trachea-esophageal fistula • Death ❖ Studies have shown an inability to accurately identify ETT cuff pressure by palpating the pilot balloon. ❖ No correlation between years in practice or number of intubations performed and the ability to properly inflate the ETT cuff or detect over inflation. ❖ Current evidence suggests that a minimum volume of air to obviate air flow past the cuff, up to a maximum pressure of less than 25cm H20, is safest to minimize complications from high ETT cuff pressures.
  52. Closed claims and the airway Originally 223 cases (1989-1997) from the records of St. Paul Fire and Marine Insurance Company. Reviewed by 8 CRNA researchers Updated recently looking at 245 claims (2003-2012 ) provided by CNA insurance company. Reviewed by 15 CRNA researchers AANA Foundation Closed Claims Analysis26
  53. Closed claims and the airway ❖ Years of experience do not appear to be a factor in terms of frequency of occurrence of adverse events. ❖ 69.8% of adverse events occurred in hospitals ❖ 68.2% of the events are confirmed to have occurred during the intra-anesthesia period but only 38.8% of the events became apparent to the provider during the intra-anesthesia period. ❖ 45.5% of negative outcomes were preventable ❖ In 32.7%, anesthesia management was deemed to have been inappropriate ❖ Respiratory events are responsible for the most common negative outcomes (31.8%). ❖ When there was a failure to meet AANA Practice Standards for Nurse Anesthetists, breach of standard #5 (includes continuous monitoring of oxygenation and ventilation) occurred 2nd most often behind breach of standard #4 AANA Foundation Closed Claims Analysis26
  54. Closed claims and the airway ❖ Established in 1985 in an attempt to improve patient safety and prevent anesthesia related injuries ❖ At the time, 11% of total dollars paid for anesthesia related patient injuries while Anesthesiologist accounted for only 3% of total physicians insured ❖ Data is derived from lawsuits regardless of the litigation outcome ASA Closed Claims Database27
  55. Closed claims and the airway ❖ Respiratory system issues accounted for 17% of all claims ❖ The most common respiratory events leading to anesthesia claims were difficult intubation, inadequate oxygenation or ventilation and pulmonary aspiration ❖ Claims arising from esophageal intubation have largely disappeared with the adoption of capnography ASA Closed Claims Database27 (1990-2007)
  56. Closed claims and the airway Respiratory events leading to claims27 (1990-2007)
  57. Closed claims and the airway Claims related to the difficult airway27 (1990-2007)
  58. Closed claims and the airway Lessons Learned27 ❖ During airway emergencies, persistent intubation attempts were associated with death or permanent brain damage ❖ The LMA was not an effective rescue device in some claims in which multiple, prolonged intubation attempts had been made ❖ Surgical airway should be instituted early in the management of the difficult airway
  59. Closed claims and the airway ❖ NAP4: National Audit Project of the Royal College of Anesthetist and the Difficult Airway Society28 ❖ Not a closed claims per se. Evaluated cases from 309 NHS hospitals in the UK over a year (2008-2009) ❖ Designed to evaluate what types of airway devices are used during anesthesia, how often complications resulting in serious harm occur and to see how this information be used to reduce the incidence of these events and complications.
  60. Closed claims and the airway ❖ NAP 4 Highlights28 • Poor airway assessment • Poor planning: Plan vs Strategy • Failure to plan for Failure • Failed use of awake FOI • Repeated intubation attempts • Supraglottic devices were used inappropriately • High failure rate of needle cricothyroidotomy • Aspiration was the single most common cause of death Poor judgment, as determined by both the reporters and the reviewers, repeatedly appeared to be the most common cause of events
  61. The Takeaway ❖ Chose the right tool for the right patient (proper preparation, strategy) ❖ Learn from other’s mistakes (closed claims)
  62. References 1. Practice Guidelines for Preoperative Fasting & the use of pharmacologic agents to reduce the risk of pulmonary aspiration: Application to healthy patients undergoing elective procedures. An Updated Report by the American Society of Anesthesiologists Task Force on Preoperative Fasting and the Use of Pharmacologic Agents to Reduce the Risk of Pulmonary Aspiration. Anesthesiology. 2017;126(3):376-393. 2. Smith I, Kranke P, Murat I, et al. Perioperative fasting in adults and children. European Journal of Anaesthesiology. 2011;28(8):556-569. doi:10.1097/eja.0b013e3283495ba1. 3. Robinson M, Davidson A. Aspiration under anesthesia: Risk assessment and decision making. Continuing Education in Anaesthesia Critical Care and Pain. 2014;14(4):171-175. 4. Miller RM et al.,eds. Miller's Anesthesia. 8th ed. Philadelphia: Saunders; 2015: 1652-1680. 5. Butterworth JF, Mackey DC, Wasnick JD, eds. Morgan & Mikhail’s Clinical Anesthesiology. 5th ed. McGraw Hill Companies. New York: 2013: 769. 6. Practice Guidelines for Obstetric Anesthesia. An Updated Report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia. Anesthesiology. 2016;124:00-00. 7. Bhatia N, Bhagat H, Sen I. Cricoid pressure: Where do we stand? J Anaesthesiol Clin Pharmacol Journal of Anaesthesiology Clinical Pharmacology. 2014;30(1):3. doi:10.4103/0970-9185.125683. 8. Stewart JC, Bhananker S, Ramaiah R. Rapid-sequence intubation and cricoid pressure. International Journal Critical Illness and Injury Science. 2014;4(1):42–49. 9. Algie CM, Mahar RK, Tan HB, Wilson G, Mahar PD, Wasiak J. Effectiveness and risks of cricoid pressure during rapid sequence induction for endotracheal intubation. Cochrane Database of Systematic Reviews. 2015. doi:10.1002/14651858.cd011656. 10. Lefave M, Harrell B, Wright M. Analysis of Cricoid Pressure Force and Technique Among Anesthesiologists, Nurse Anesthetists, and Registered Nurses. Journal of PeriAnesthesia Nursing. 2016;31(3):237-244. 11. Lundstrom LH, Vester-Andersen M, Moller AM, Charuluxananan S, L'hermite J, Wetterslev J. Poor prognostic value of the modified Mallampati score: a meta-analysis involving 177 088 patients. British Journal of Anaesthesia. 2011;107(5):659-667. 12. El-Ganzouri AR, Mccarthy RJ, Tuman KJ, Tanck EN, Ivankovich AD. Preoperative Airway Assessment. Anesthesia & Analgesia. 1996;82(6):1197-1204. doi:10.1213/00000539-199606000-00017. 13. Corso RM, Cattano D, Buccioli M, Carretta E, Maitan S. Post analysis simulated correlation of the El-Ganzouri airway difficulty score with difficult airway. Brazilian Journal of Anesthesiology (English Edition). 2016;66(3):298-303. doi:10.1016/j.bjane.2014.09.003. 14. El-Orbany M, Woehlc H, Salem M. Head and neck position for direct laryngoscopy. Anesthesia and Analgesia. 2011;133:103-109. doi:10.1213/ane.0b013e31821c7e9c. 15. Walls RM, Murphy MF. Manual of Emergency Airway Management, 4th Ed Philadelphia: Lippincott Williams and Wilkins; 2012.
  63. References 16. Standards for Nurse Anesthesia Practice. American Association of Nurse Anesthetists website. http://www.aana.com/resources2/professionalpractice/Pages/Scope-of-Nurse-Anesthesia-Practice.aspx. Updated 2013. Accessed June 12, 2016. 17. Michalek P, Donaldson W, Vobrubova E, Hakl M. Complications Associated with the Use of Supraglottic Airway Devices in Perioperative Medicine. BioMed Research International. 2015;2015:1-13. doi:10.1155/2015/746560. 18. Kang J-E, Oh C-S, Choi JW, Son IS, Kim S-H. Postoperative Pharyngolaryngeal Adverse Events with Laryngeal Mask Airway (LMA Supreme) in Laparoscopic Surgical Procedures with Cuff Pressure Limiting 25 : Prospective, Blind, and Randomised Study. The Scientific World Journal. 2014;2014:1-7. doi:10.1155/2014/709801. 19. Cook T, Howes B. Supraglottic Airway devices: Recent Advances. Contin Educ Anaesth Crit Care Pain Continuing Education in Anaesthesia, Critical Care & Pain. 2011;11(2):56-61. 10.1093/bjaceaccp/mkq058. 20. Whitacre W, Dieckmann L, Austin PN. An Update: Use of Laryngeal Mask Airway Devices in Patients in the Prone Position; AANA Journal. 2014:82(2). 21. Caldiroli D, Cortellazi P. A new difficult airway management algorithm based upon the El Ganzouri Risk Index and GlideScope videolaryngoscope. A new look for intubation? Minerva Anestesiologica. 2011;77(10):1011-7. 22. Diaz-Gomez JL, Satyapirya A, Satyapriya SV et al. Standard clinical risk factors for difficult laryngoscopy are not independent predictors of intubation success with the GlideScope. Journal of Clinical Anesthesia. 2011; 23(8):603-610 doi:10.1016/j.jclinane.2011.03.006. 23. Saxena, N. (2013). Airway management plan in patients with difficult airways having regional anesthesia. J Anaesthesiology Clin Pharmacol Journal of Anaesthesiology Clinical Pharmacology. 2013:29(4):558 doi.org/10.4103/0970-9185.119106. 24. Weingart SD, Levitan RM. Preoxygenation and prevention of desaturation during emergency airway management. Annals of Emergency Medicine. 2012;59(3):165-175. doi:10.1016/j.annemergmed.2011.10.002. 25. Sultan P, Carvalho B, Rose BO, Cregg R. Endotracheal tube cuff pressure monitoring: a review of the evidence. Journal of Perioperative Practice. 2011:21(11). 26. Jordan LM, Quraishi. The AANA Foundation Malpractice Closed Claims Study: A Descriptive Analysis. AANA Journal. 2015;83(5); 318-323. 27. Metzner J, Posner KL, Lam MS, Domino KB. Closed claims’ analysis. Best Practice & Research Clinical Anaesthesiology. 2011;25(2)263-276. doi:10.1016/j.bpa.2011.02.007. 28. Cook TM, Woodall N, Frerk C. Major complications of airway management in the UK: results of the Fourth National Audit Project of the Royal College of Anaesthetists and the Difficult Airway Society. Part 1: Anaesthesia. British Journal of Anaesthesia. 2011;106(5):617–631. doi: 10.1093/bja/aer058. 29. Reitman E, Flood P. Anaesthetic considerations for non-obstetric surgery during pregnancy. British Journal of Anaesthesia. 2011;107(suppl 1):i72-I78. doi:10.1093/bja/aer343.