Practice Guidelines for Management of the Difficult Airway: An Updated Report

American Society of Anesthesiologists

Bibliography by Section

I. Evaluation of the Airway

Patient condition (patient characteristics associated with difficult airway).

Difficult airway patients/subjects:

Observational studies, case reports, or comparisons without pertinent control groups

  1. Asai T, Hirose T, Shingu K: Failed tracheal intubation using a laryngoscope and intubating laryngeal mask. Can J Anesth 2000; 47:325-328
  2. Azizkhan RG, Dudgeon DL, Buck JR, Colombani PM, Yaster M, Nichols D, Civin C, Kramer SS, Haller JAJ: Life-threatening airway obstruction as a complication to the management of mediastinal masses in children. J Pediatr Surg 1985; 20:816-822
  3. Baines D, Keneally J: Anaesthetic implications of the mucopolysaccharidoses: a fifteen-year experience in a children's hospital. Anaesth Intens Care 1983; 11:198-202
  4. Bittar D: Respiratory obstruction associated with induction of general anesthesia in a patient with mediastinal Hodgkin's disease. Anesth Analg 1975; 54:399-403
  5. Brechner VL: Unusual problems in the management of airways: flexion-extension mobility of the cervical vertebrae. Anesth Analg 1968 47:362-373
  6. Brock-Utne JG, Downing JW, Seedat F: Laryngeal oedema associated with pre-eclampic toxaemia. Anaesthesia 1977; 32:556-558
  7. Buckland RW, Pedley J. Lingual thyroid--a threat to the airway. Anaesthesia 2000, 55:1103-1105
  8. Capistrano Baruh E, Wenig B, Steinberg L, Stegnjajic A, Baruh S: Laryngeal web: a cause of difficult endotracheal intubation. Anesthesiology 1982; 57:123-125
  9. Chen PT, Chang WK, Hsu WH, Sung CS, Chan KH, Tsai SK: Anesthetic management of a patient undergoing segmental resection of trachea with an endotracheal neurofibroma and nearly total occlusion of trachea. Acta Anaesthesiol Taiwan 2004; 42:233-236
  10. Coonan TJ, Hope CE, Howes WJ, Holness RO, MacInnis EL: Ankylosis of the temporo-mandibular joint after temporal craniotomy: a cause of difficult intubation. Can Anaesth Soc J 1985; 32:158-160
  11. Daum RE, Jones DJ: Fibreoptic intubation in Klippel-Feil syndrome. Anaesthesia 1988; 43:18-21
  12. Divekar VM, Kothari MD, Kamdar BM: Anaesthesia in Turner's syndrome. Can Anaesth Soc J 1983; 30:417-418
  13. Domino KB, Posner KL, Caplan RA, Cheney FW: Airway injury during anesthesia. Anesthesiology 1999; 91:1703-1711
  14. Ferrari LR, Bedford RF: General anesthesia prior to treatment of anterior mediastinal masses in pediatric cancer patients. Anesthesiology 1990; 72:991-995
  15. Finucane BT: Difficult intubation associated with the foetal alcohol syndrome. Can Anaesth Soc J 1980; 27:574-575
  16. Gallagher DM, Hyler RL, Epker BN: Hemifacial microsomia: an anesthetic airway problem. Oral Surg, Oral Med, Oral Path 1980; 49:2-4
  17. Gist RS, Miller DW, Warren T: A difficult airway in a patient with nephrogenic sclerosing fibrosis. Anesth Analg 2010; 110:555-557
  18. Hill CM: Death following dental clearance in a patient suffering from ankylosing spondylitis - a case report with discussion on management of such problems. Br J Oral Surg 1980; 18:73-76
  19. James I, Wark H: Airway management during anesthesia in patients with epidermolysis bullosa dystrophica. Anesthesiology 1982; 56:323-326
  20. Jouppila R, Jouppila P, Hollm'en A: Laryngeal oedema as an obstetric anaesthesia complication: case reports. Acta Anaesth Scand 1980; 24:97-98
  21. Kariya N, Nishi S, Minami W, Funao T, Mori M, Nishikawa K, Asada A: Airway problems related to laryngeal mask airway use associated with an undiagnosed epiglottic cyst. Anaesth Intensive Care 2004; 32:268-270
  22. Kawai T, Shimozato K, Ochiai S: Elongated styloid process as a cause of difficult intubation. J Oral Maxillofac Surg 1990; 48:1225-1228
  23. Kempthorne PM, Brown TC: Anaesthesia and the mucopolysaccharidoses: a survey of techniques and problems. Anaesth Intens Care 1983; 11:203-207
  24. Kitahata LM: Airway difficulties associated with anaesthesia in acromegaly: three case reports. Br J Anaesth 1971; 43:1187-1190
  25. Lee HC, Andree RA: Cervical spondylosis and difficult intubation. Anesth Analg 1979; 58:434-435
  26. Levitt MW, Collison JM: Difficult endotracheal intubation in a patient with pseudoxanthoma elasticum. Anaesth Intens Care 1982; 10:62-64
  27. Li Pi Shan W, Hatzakorzian R, Sherman M, Backman SB: Upper airway compromise secondary to edema in Graves' disease. Can J Anaesth 2006; 53:183-187
  28. Mackie AM, Watson CB: Anaesthesia and mediastinal masses. A case report and review of the literature. Anaesthesia 1984; 39:899-903
  29. McGoldrick KE, Donlon JV: Sublingual hematoma following difficult laryngoscopy. Anesth Analg 1979; 58:343-344
  30. Miyabe M, Dohi S, Homma E: Tracheal intubation in an infant with Treacher-Collins syndrome--pulling out the tongue by a forceps. Anesthesiology 1985; 62:213-214
  31. Nagamine Y, Kurahashi K: The use of three-dimensional computed tomography images for anticipated difficult intubation airway evaluation of a patient with Treacher Collins syndrome. Anesth Analg 2007; 105:626-628
  32. Nakazawa K, Ikeda D, Ishikawa S, Makita K: A case of difficult airway due to lingual tonsillar hypertrophy in a patient with Down's syndrome. Anesth Analg 2003; 97:704-705
  33. Neuman GG, Weingarten AE, Abramowitz RM, Kushins LG, Abramson AL, Ladner W: The anesthetic management of the patient with an anterior mediastinal mass. Anesthesiology 1984; 60:144-147
  34. Nitahara K, Watanaoe R, Katori K, Yamasato M, Matsunaga M, Dan K: Intubation of a child with a difficult airway using a laryngeal mask airway and a guidewire and jet stylet. Anesthesiology 1999; 91:330-331
  35. Northrip DR, Bohman BK, Tsueda K: Total airway occlusion and superior vena cava syndrome in a child with an anterior mediastinal tumor. Anesth Analg 1986; 65:1079-1082
  36. O'Leary HT, Tracey JA: Mediastinal tumours causing airway obstruction. A case in an adult. Anaesthesia 1983; 38:67
  37. Piro A, Weiss D, Hellman S: Mediastinal Hodgkin's disease: a possible danger for intubation anesthesia. J Radiat Onc Bio Phys 1976; 1:415-419
  38. Ramamani M, Ponnaiah M, Bhaskar S, Rai E: An uncommon cause of unanticipated difficult airway. Paediatr Anaesth 2009; 19:643-645
  39. Rasch DK, Browder F, Barr M, Greer D: Anaesthesia for Treacher Collins and Pierre Robin syndromes: a report of three cases. Can Anaesth Soc J 1986; 33:364-370
  40. Roa NL, Moss KS: Treacher-Collins syndrome with sleep apnea: anesthetic considerations. Anesthesiology 1984; 60:71-73
  41. Rocke DA, Murray WB, Rout CC, Gouws E: Relative risk analysis of factors associated with difficult intubation in obstetric anesthesia. Anesthesiology 1992; 77:67-73
  42. Salzarulo HH, Taylor LA: Diabetic "stiff joint syndrome" as a cause of difficult endotracheal intubation. Anesthesiology 1986; 64:366-368
  43. Schoenhage KO, Koenig HM: Unanticipated difficult endotracheal intubations in patients with cervical spine instrumentation. Anesth Analg 2006; 102:960-963
  44. Sjogren P, Pedersen T: Anaesthetic problems in Hurler-Scheie syndrome. Report of two cases. Acta Anaesth Scand 1986; 30:484-486
  45. Tunstall ME, Geddes C: "Failed intubation" in obstetric anaesthesia. An indication for use of the "Esophageal Gastric Tube Airway". Br J Anaesth 1984; 56:659-661
  46. Van Heerden PV, Kirrage D: Large tonsils and the laryngeal mask airway. Anaesthesia 1989; 44:703
  47. Walls RD, Timmis DP, Finucaine BT: Difficult intubation associated with calcified stylohyoid ligament. Anaesth Intensive Care 1990; 18:110-112
  48. Weinberg S, Kravath R, Phillips L, Mendez H, Wolf GL: Episodic complete airway obstruction in children with undiagnosed obstructive sleep apnea. Anesthesiology 1984; 60:356-358

Non-difficult airway or mixed patients/subjects:

Observational studies, case reports, or non-pertinent comparison groups

  1. Berthoud MC, Peacock JE, Reilly CS: Effectiveness of preoxygenation in morbidly obese patients. Br J Anaesth 1991; 67:464-466
  2. Bouaggad A, Nejmi SE, Bouderka MA, Abbassi O: Prediction of difficult intubation in thyroid surgery. Anesth Analg 2004; 99:603-606
  3. 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. Br J Anaesth 2011; 106:517-631
  4. Ezri T, Medalion B, Wesienberg M, Szmuk P, Warters D, Charuzi I: Increased body mass index per se is not a predictor of difficult laryngoscopy. Can J Anaesth 2003; 50:179-183
  5. Hagberg CA, Vogt-Harenkamp C, Kamal J: A retrospective analysis of airway management in obese patients at a teaching institution. J Clin Anesth 2009; 21:348-351
  6. Heinrich S, Birkholz T, Ihmsen H, Irouschek A, Ackermann A, Schmidt J: Incidence and predictors of difficult laryngoscopy in 11.219 pediatric anesthesia procedures. Paediatr Anaesth 2012; 22:729-736
  7. Juvin P, Lavaut E, Dupont H, Dupont H, Lefevre P, Demetriou M, Dumoulin JL, Desmonts JM: Difficult intubation is more common in obese than in lean patients. Anesth Analg 2003; 97:595-600
  8. Kheterpal S, Martin L, Shanks AM, Tremper KK: Prediction and outcomes of impossible mask ventilation: a review of 50,000 anesthetics. Anesthesiology 2009; 110:891-897
  9. Langeron O, Masso E, Huraux C, Guggiari M, Bianchi A, Coriat P, Riou B: Prediction of difficult mask ventilation. Anesthesiology 2000; 92:1229-1236
  10. Wong SH, Hung CT: Prevalence and prediction of difficult intubation in Chinese women. Anaesth Intensive Care 1999; 27:49-52

Directed airway physical examination.

Difficult airway patients/subjects:

Observational studies, case reports, or comparisons without pertinent control groups

  1. Samsoon GL, Young JR: Difficult tracheal intubation: a retrospective study. Anaesthesia 1987; 42:487-490
  2. Uerpairojkit K, Pranootnarabhal T, Punjasawadwong Y, Chumnanvej S, Tanudsintum S, Wasinwong W, Pengpol W: Multicentered study of model of difficult endotracheal intubation by incident reports from university and non-university hospitals. J Med Assoc Thai 2008; 91:1846-1852

Non-difficult airway or mixed patients/subjects:

Observational studies, case reports, or non-pertinent comparison groups

  1. Brodsky JB, Lemmens HJ, Brock-Utne JG, Vierra M, Saidman LJ: Morbid obesity and tracheal intubation. Anesth Analg 2002; 95:732-736
  2. Butler PJ, Dhara SS: Prediction of difficult laryngoscopy: an assessment of the thyromental distance and the Mallampati predictive tests. Anaesth Intens Care 1992; 20:139-142
  3. Cattano D, Panicucci E, Paolicchi A, Forfori F, Giunta F, Hagberg C: Risk factors assessment of the difficult airway: an Italian survey of 1956 patients. Anesth Analg 2004; 99:1771-1779
  4. Ezri T, Warters D, Szmuk P, Saad-Eddin H, Geva D, Katz J, Hagberg C: The incidence of class "zero" airway and the impact of Mallampati score, age, sex, and body mass index on prediction of laryngoscopy grade. Anesth Analg 2001; 93:1073-1075
  5. Gupta S, Pareek S, Dulara SC: Comparison of two methods for predicting difficult intubation in obstetric patients. Middle East J Anesthesiol 2003; 17:275-285
  6. Hagberg CA, Vogt-Harenkamp C, Kamal J: A retrospective analysis of airway management in obese patients at a teaching institution. J Clin Anesth 2009; 21:348-351
  7. Juvin P, Lavaut E, Dupont H, Dupont H, Lefevre P, Demetriou M, Dumoulin JL, Desmonts JM: Difficult intubation is more common in obese than in lean patients. Anesth Analg 2003; 97:595-600
  8. Kheterpal S, Martin L, Shanks AM, Tremper KK: Prediction and outcomes of impossible mask ventilation: a review of 50,000 anesthetics. Anesthesiology 2009; 110:891-897
  9. Mallampati SR, Gatt SP, Gugino LD, Desai SP, Waraksa B, Freiberger D, Liu PL: A clinical sign to predict difficult tracheal intubation: a prospective study. Can Anaesth Soc J 1985; 32:429-434
  10. McCrory CR, Moriarty DC: Laryngeal mask airway positioning is related to Mallampati grading in adults. Anesth Analg 1995; 81:1001-1004
  11. Neligan PJ, Porter S, Max B, Malhotra G, Greenblatt EP, Ochroch EA: Obstructive sleep apnea is not a risk factor for difficult intubation in morbidly obese patients. Anesth Analg 2009; 109:1182-1186
  12. Oates JD, Macleod AD, Oates PD, Pearsall FJ, Howie JC, Murray GD: Comparison of two methods for predicting difficult intubation. Br J Anaesth 1991; 66:305-309
  13. Pilkington S, Carli F, Dakin MJ, Romney M, De Witt KA, Dore CJ, Cormack RS: Increase in Mallampati score during pregnancy. Br J Anaesth 1995; 74:638-642
  14. Rose DK, Cohen M: The airway: problems and predictions in 18,500 patients. Can J Anaesth 1994; 41:372-383
  15. Rosenblatt W, Ianus AI, Sukhupragarn W, Fickenscher A, Sasaki C: Preoperative endoscopic airway examination (PEAE) provides superior airway information and may reduce the use of unnecessary awake intubation. Anesth Analg 2011; 112:602-607
  16. Savva D: Prediction of difficult tracheal intubation. J Anaesthesia 1994; 73:149-153
  17. Tremblay MH, Williams S, Robitaille A, Drolet P: Poor visualization during direct laryngoscopy and high upper lip bite test score are predictors of difficult intubation with the GlideScope videolaryngoscope. Anesth Analg 2008; 106:1495-1500
  18. Tse JC, Rimm EB, Hussain A: Predicting difficult endotracheal intubation in surgical patients scheduled for general anesthesia: a prospective blind study. Anesth Analg 1995; 81:254-258
  19. Wilson ME, Spiegelhalter D, Robertson JA, Lesser P: Predicting difficult intubation. Br J Anaesth 1988; 61:211-216

Diagnostic tests.

Difficult airway patients/subjects:

Observational studies, case reports, or comparisons without pertinent control groups

  1. Aoi Y, Kamiya Y, Shioda M, Furuya R, Yamada Y: Pre-anesthetic evaluation can play a crucial role in the determination of airway management in a child with oropharyngeal tumor. J Anesth 2006; 20:215-219
  2. Daum RE, Jones DJ: Fibreoptic intubation in Klippel-Feil syndrome. Anaesthesia 1988; 43:18-21
  3. Fahy L, Horton WA, Charters P: Factor analysis in patients with a history of failed tracheal intubation during pregnancy. 1990; Br J Anaesth 65:813-815
  4. Heindel DJ: Deep neck abscesses in adults: management of a difficult airway. Anesth Analg 1987; 66:774-776
  5. Kawai T, Shimozato K, Ochiai S: Elongated styloid process as a cause of difficult intubation. J Oral Maxillofac Surg 1990; 48:1225-1228
  6. Keenan MA, Stiles CM, Kaufman RL: Acquired laryngeal deviation associated with cervical spine disease in erosive polyarticular arthritis. Anesthesiology 1983; 58:441-449
  7. Murashima K, Fukutome T: Jaw thrust manoeuvre for repositioning the epiglottis down folded by the ILM. Anaesthesia 2000; 55:921-922
  8. Pollard BA, El-Beheiry H: Pott's disease with unstable cervical spine, retropharyngeal cold abscess and progressive airway obstruction. Can J Anaesth 1999; 46:772-775
  9. Sharwood-Smith GH: Difficulty in intubation. Calcified stylohyoid ligament. Anaesthesia 1976; 31:508-510

Non-difficult airway or mixed patients/subjects:

Observational studies, case reports, or non-pertinent comparison groups

  1. Bellhouse CP, Dor'e C: Criteria for estimating likelihood of difficulty of endotracheal intubation with the Macintosh laryngoscope. Anaesth Intens Care 1988; 16:329-337
  2. Lyons G: Failed intubation. Six years' experience in a teaching maternity unit. Anaesthesia 1985; 40:759-762
  3. White A, Kander PL: Anatomical factors in difficult direct laryngoscopy. Br J Anaesth 1975; 47:468-474

II. Basic Preparation for Difficult Airway Management

Preanesthetic preoxygenation by mask.

Difficult airway patients/subjects:

Observational studies, case reports, or comparisons without pertinent control groups

  1. Baillard C, Fosse JP, Sebbane M, Chanques G, Vincent F, Courouble P, Cohen Y, Eledjam JJ, Adnet F, Jaber S: Noninvasive ventilation improves preoxygenation before intubation of hypoxic patients. Am J Respir Crit Care Med 2006; 174:171-177
  2. Mort TC, Waberski BH, Clive J: Extending the preoxygenation period from 4 to 8 mins in critically ill patients undergoing emergency intubation. Crit Care Med 2009; 37:68-71

Non-difficult airway or mixed patients/subjects:

Randomized controlled trials

  1. Haynes SR, Allsop JR, Gillies WA: Arterial oxygen saturation during induction of anaesthesia and laryngeal mask insertion: prospective evaluation of four techniques. Br J Anaesth 1992; 68:519-522

Observational studies, case reports, or non-pertinent comparison groups

  1. Altermatt FR, Muñoz HR, Delfino AE, Cortínez LI: Pre-oxygenation in the obese patient: effects of position on tolerance to apnoea. Br J Anaesth 2005; 95:706-709
  2. Drummond GB, Park GR: Arterial oxygen saturation before intubation of the trachea. An assessment of oxygenation techniques. Br J Anaesth 1984; 56:987-993
  3. Lane S, Saunders D, Schofield A, Padmanabhan R, Hildreth A, Laws D: A prospective, randomised controlled trial comparing the efficacy of pre-oxygenation in the 20 degrees head-up vs supine position. Anaesthesia 2005; 60:1064-1067

Preanesthetic preoxygenation for 3-5 minutes.

Non-difficult airway or mixed patients/subjects:

Randomized controlled trials

  1. Baraka AS, Taha SK, Aouad MT, El-Khatib M, Kawkabani NI: Preoxygenation: Comparison of maximal breathing and tidal volume breathing techniques. Anesthesiology 1999; 91:612-616
  2. Chiron B, Mas C, Ferrandière M, Bonnard C, Fusciardi J, Mercier C, Laffon M: Standard preoxygenation vs two techniques in children. Paediatr Anaesth 2007; 17:963-967
  3. Gambee AM, Hertzka R, Fisher D: Preoxygenation techniques: Comparison of three minutes and 4 breaths. Anesth Analg 1987; 66:468-470
  4. Goldberg ME, Norris MC, Laryani GE, Marr AT, Seltzer JL: Preoxygenation in the morbidly obese: A comparison of two techniques. Anesth Analg 1989; 68:520-522
  5. Norris MC, Dewan DM: Preoxygenation for cesarean section: A comparison of two techniques. Anesthesiology 1985; 62:827-829
  6. Valentine SJ, Marjot R, Monk CR: Preoxygenation in the elderly: A comparison of the 4-maximal breath and 3-minute techniques. Anesth Analg 1990; 71:516-519
  7. Videira RLR, Neto PPR, Gomide do Amaral RV, Freeman JA: Preoxygenation in children: for how long? Acta Anaesth Scand 1992; 36:109-111
  8. Xue FS, Tong SY, Wang XL, Deng XM, An G: Study of the optimal duration of preoxygenation in children. J Clin Anesth 1995; 7:93-96

Nonrandomized comparative studies

  1. Gold MI, Durate I, Muravchick S: Arterial oxygenation in conscious patients after 5 minutes and after 30 seconds of oxygen breathing. Anesth Analg 1981; 60:313-315
  2. McCarthy G, Elliott P, Mirakhur K, McLaughlin C: A comparison of different preoxygenation techniques in the elderly. Anaesthesia 1991; 46:824-827

Observational studies, case reports, or non-pertinent comparison groups

  1. Berthoud M, Read DH, Norman J: Pre-oxygenation: how long? Anaesthesia 1983; 38:96-102
  2. Butler PJ, Mujnro HM, Kenny MB: Preoxygenation in children using expired oxygraphy. Br J anaesth 1996; 77:333-334
  3. Choiniere A, Girard F, Boudreault D, Ruel M, Girard DC: Voluntary hyperventilation before a rapid-sequence induction of anesthesia does not decrease postintubation PaCO2. Anesth Analg 2001; 93:1277-1280
  4. Machlin HA, Myles PS, Berry CB: End-tidal oxygen measurement compared with patient factor assessment for determining preoxygenation time. Anaesth Intens Care 1993; 21:409-413
  5. Morrison JE, Collier E, Friesen RH, Logan L: Preoxygenation before laryngoscopy in children: how long is enough? Paediat Anaesth 1998; 8:293-298

III. Strategies for Intubation/Ventilation

Awake intubation.

Difficult airway patients/subjects:

Observational studies, case reports, or comparisons without pertinent control groups

  1. Abramson SI, Holmes AA, Hagberg CA: Awake insertion of the Bonfils Retromolar Intubation Fiberscope™ in five patients with anticipated difficult airways. Anesth Analg 2008; 106:1215-1217
  2. Asai T, Matsumoto H, Shingu K: Awake tracheal intubation through the intubating laryngeal mask. Can J Anesth 1999; 46:182-184
  3. Asai T, Nagata A, Shingu K: Awake tracheal intubation through the laryngeal mask in neonates with upper airway obstruction. Paediatr Anaesth 2008; 18:77-80
  4. Buckland RW, Pedley J. Lingual thyroid--a threat to the airway. Anaesthesia 2000, 55:1103-1105
  5. Cohn AI, McGraw SR, King WH: Awake intubation of the adult trachea using the Bullard laryngoscope. Can J Anaesth 1995; 42:246-248
  6. Cohn AI, Zornow MH: Awake endotracheal intubation in patients with cervical spine disease: a comparison of the Bullard laryngoscope and the fiberoptic bronchoscope. Anesth Analg 1995; 81:1283-1286
  7. Dimitriou VK, Zogogiannis ID, Liotiri DG: Awake tracheal intubation using the Airtraq laryngoscope: a case series. Acta Anaesthesiol Scand 2009; 53:964-967
  8. Edwards RM, Hunt TL: Blind nasal intubation in an awake patient for cesarean section. Anesth Intens Care 1982; 10:151-153
  9. Joo HS, Kapoor S, Rose DK, Naik VN: The intubating laryngeal mask airway after induction of general anesthesia versus awake fiberoptic intubation in patients with difficult airways. Anesth Analg 2001; 92:1342-1346
  10. Kim JS, Park SY, Min SK, Kim JH, Lee SY, Moon BK: Awake nasotracheal intubation using fiberoptic bronchoscope in a pediatric patient with Freeman-Sheldon syndrome. Paediatr Anaesth 2005; 15:790-792
  11. Kovacs G, Law AJ, Petrie D: Awake fiberoptic intubation using an optical stylet in an anticipated difficult airway. Ann Emerg Med 2007; 49:81-83
  12. Kulka PJ, Tryba M, Zenz M: Difficult airway management in a patient with severe aortic stenosis, coronary artery disease, and heart failure. J Clin Anesth 2002; 14:150-153
  13. Larson SM, Parks DH: Managing the difficult airway in patients with burns of the head and neck. J Burn Care Rehabil 1988; 9:55-56
  14. Lee HC, Andree RA: Cervical spondylosis and difficult intubation. Anesth Analg 1979; 58:434-435
  15. Maktabi MA, Hoffman H, Funk G, From RP: Laryngeal trauma during awake fiberoptic intubation. Anesth Analg 2002; 95:1112-1114
  16. McCrirrick A, Pracilio JA: Awake intubation: a new technique. Anaesthesia 1991; 46:661-663
  17. McGuire G, El-Beheiry H: Complete upper airway obstruction during awake fibreoptic intubation in patients with unstable cervical spine fracture. Can J Anaesth 1999; 46:176-178
  18. Mishkel L, Wang JF, Gutierrez F, Ballard JB: Nasotracheal intubation by fiberoptic laryngoscope. South Med J 1981; 74:1407-1409
  19. Mongan PD, Culling RD: Rapid oral anesthesia for awake intubation. J Clin Anesth 1992; 4:101-105
  20. Ovassapian A, Krejcie TC, Yelich SJ, Dykes MH: Awake fibreoptic intubation in the patient at high risk of aspiration. Br J Anaesth 1989; 62:13-16
  21. Palmer JHM, Ball DR: Awake tracheal intubation with the intubating laryngeal mask in a patient with diffuse idiopathic skeletal hyperostosis. Anaesthesia 2000; 55:70-78
  22. Pandey R, Garg R, Kumar A, Darlong V, Punj J, Singh SA: Case report: Airway management of a patient with popping pedunculated subglottic laryngeal polyp. Acta Anaesthesiol Belg 2009; 60:251-253
  23. Parnell JD, Mills J: Awake intubation using fast-track laryngeal mask airway as an alternative to fiberoptic bronchoscopy: a case report. AANA J 2006; 74:429-431
  24. Pellis T, Leykin Y, Albano G, Zannier G, Di Capua G, Marzano B, Gullo A: Perioperative management and monitoring of a super-obese patient. Obes Surg 2004; 14:1423-1427
  25. Reasoner DK, Warner DS, Todd MM, Hunt SW, Kirchner J: A comparison of anesthetic techniques for awake intubation in neurosurgical patients. J Neurosurg Anesth 1995; 7:94-99
  26. Redden RL, Biery KA, Campbell RL: Arterial oxygen desaturation during awake endotracheal intubation. Anesth Prog 1990; 37:201-204
  27. Saha AK, Higgins M, Walker G, Badr A, Berman L: Comparison of awake endotracheal intubation in patients with cervical spine disease: the lighted intubating stylet versus the fiberoptic bronchoscope. Anesth Analg 1998; 87:477-479
  28. Shaw JC, Welchew EA, Harrison BJ, Michael S: Complete airway obstruction during awake fibreoptic intubation. Anaesthesia 1997; 52:582-585
  29. Shung J, Avidan MS, Ing R, Klein DC, Pott L: Awake intubation of the difficult airway with the intubating laryngeal mask airway. Anaesthesia 1998; 53:645-649
  30. Sidhu V, Whitehead E, Ainsworth Q, Smith M, Calder I: A technique of awake fibreoptic intubation: experience in patients with cervical spine disease. Anaesthesia 1993; 48:910-913
  31. Suzuki A, Toyama Y, Iwasaki H, Henderson J: Airtraq for awake tracheal intubation. Anaesthesia 2007; 62:746-747
  32. Teo YK: A difficult airway in a patient with extensive cervical lymphadenopathy. Anaesth Intensive Care 2009; 37:866-867
  33. Wong JK, Tongier WK, Armbruster SC, White PF: Use of the intubating laryngeal mask airway to facilitate awake orotracheal intubation in patients with cervical spine disorders. J Clin Anesth 1999; 11:346-348

Non-difficult airway or mixed patients/subjects: