Comparing “Acromio-Axillo-Suprasternal Notch Index (AASI)” as a New Screening Test for Predicting Difficult Laryngoscopy with Four Commonly Used Tests

Document Type : Original Article (s)

Authors

1 Professor, Department of Anesthesiology and Critical Care, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

2 Student of Medicine, School of Medicine AND Student research Committee, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Background: Prediction of difficult laryngoscopy is an essential part of airway management in general anesthesia .The purpose of the present study was comparison of commonly used tests of prediction of difficult laryngoscopy and endotracheal intubation ratio of height to thyromental distance (RHTMD), Modified Mallampati test (MMT), upper lip bite test (ULBT), ratio of neck circumference to thyromental distance (NC/TMD) with acromio-axillo-suprasternal notch index (AASI) in general anesthesia.Methods: A total of 728 patients scheduled for surgery under general anesthesia with endotracheal intubation were enrolled in this study. The dimensional predictive test measurements (AASI, ULBT, RHTMD, NC/TMD, MMT) were accomplished on all patients. The laryngoscopic view was graded with Cormack-Lehane (CL) grading system. Receiver operating characteristic (ROC) curve, Sensitivity, specificity, and Positive predictive value (PPV) were used to compare the tests.Findings: Our study showed that the incidence of difficult view laryngoscopy (DVL) is about 2.9%. AASI had the highest specificity, positive likelihood ratio, PPV and NPV in comparison with the other predictive tests. AASI with cutoff point ≤ 0.6 had the higher cut off point. AASI has the highest ROC with significant difference to other prediction tests. RHTMD had the least sensitivity.Conclusion: Our study showed that AASI can be a good screening test to predict difficult laryngoscopy in general anesthesia.

Keywords


  1. Lapinsky SE. Endotracheal intubation in the ICU. Crit Care 2015; 19: 258.
  2. Cook TM, MacDougall-Davis SR. Complications and failure of airway management. Br J Anaesth 2012; 109(Suppl 1): i68-i85.
  3. Nolan JP, Kelly FE. Airway challenges in critical care. Anaesthesia 2011; 66(Suppl 2): 81-92.
  4. 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(3): 305-9.
  5. Rocke DA, Murray WB, Rout CC, Gouws E. Relative risk analysis of factors associated with difficult intubation in obstetric anesthesia. Anesthesiology 1992; 77(1): 67-73.
  6. Chou HC, Wu TL. Thyromental distance--shouldn't we redefine its role in the prediction of difficult laryngoscopy? Acta Anaesthesiol Scand 1998; 42(1): 136-7.
  7. Turkan S, Ates Y, Cuhruk H, Tekdemir I. Should we reevaluate the variables for predicting the difficult airway in anesthesiology? Anesth Analg 2002; 94(5): 1340-4, table.
  8. Bilgin H, Ozyurt G. Screening tests for predicting difficult intubation. A clinical assessment in Turkish patients. Anaesth Intensive Care 1998; 26(4): 382-6.
  9. Kamranmanash MR, Jafari A, Gharaee B, Agha Mohammadi H, Poorzamani M, Kashi AH. Comparing the new acromio-axillo-suprasternal notch index with modified Mallampati test in the prediction of difficult laryngeal exposure. J Iran Society Anaesthesiol Intensive Care 2012; 34(79): 7-14. [In Persian].
  10. Khan ZH, Mohammadi M, Rasouli MR, Farrokhnia F, Khan RH. The diagnostic value of the upper lip bite test combined with sternomental distance, thyromental distance, and interincisor distance for prediction of easy laryngoscopy and intubation: a prospective study. Anesth Analg 2009; 109(3): 822-4.
  11. Samsoon GL, Young JR. Difficult tracheal intubation: a retrospective study. Anaesthesia 1987; 42(5): 487-90.
  12. Schmitt HJ, Kirmse M, Radespiel-Troger M. Ratio of patient's height to thyromental distance improves prediction of difficult laryngoscopy. Anaesth Intensive Care 2002; 30(6): 763-5.
  13. Hirmanpour A, Safavi M, Honarmand A, Jabalameli M, Banisadr G. The predictive value of the ratio of neck circumference to thyromental distance in comparison with four predictive tests for difficult laryngoscopy in obstetric patients scheduled for caesarean delivery. Adv Biomed Res 2014; 3: 200.
  14. Kim WH, Ahn HJ, Lee CJ, Shin BS, Ko JS, Choi SJ, et al. Neck circumference to thyromental distance ratio: a new predictor of difficult intubation in obese patients. Br J Anaesth 2011; 106(5): 743-8.
  15. Honarmand A, Safavi M, Ansari N. A comparison of between hyomental distance ratios, ratio of height to thyromental, modified Mallamapati classification test and upper lip bite test in predicting difficult laryngoscopy of patients undergoing general anesthesia. Adv Biomed Res 2014; 3: 166.
  16. Etezadi F, Ahangari A, Shokri H, Najafi A, Khajavi MR, Daghigh M, et al. Thyromental height: a new clinical test for prediction of difficult laryngoscopy. Anesth Analg 2013; 117(6): 1347-51.
  17. 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. Br J Anaesth 2011; 107(5): 659-67.
  18. Krage R, van Rijn C, van Groeningen D, Loer SA, Schwarte LA, Schober P. Cormack-Lehane classification revisited. Br J Anaesth 2010; 105(2): 220-7.
  19. Practice guidelines for obstetric anesthesia: an updated report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia. Anesthesiology 2007; 106(4): 843-63.
  20. Merah NA, Foulkes-Crabbe DJ, Kushimo OT, Ajayi PA. Prediction of difficult laryngoscopy in a population of Nigerian obstetric patients. West Afr J Med 2004; 23(1): 38-41.
  21. Gonzalez H, Minville V, Delanoue K, Mazerolles M, Concina D, Fourcade O. The importance of increased neck circumference to intubation difficulties in obese patients. Anesth Analg 2008; 106(4): 1132-6, table.