Are anatomical landmark measurements accurate for predicting endotracheal tube depth?
Abstract
Background: A traditional method for depth of intubation in adult patients is taping the endotracheal tube (ETT) at the upper incisors a distance of 21 or 23 cm for women and men respectively (21/23 method). A novel “topographical” measurement for estimating proper intubation depth has been suggested as a better depth predictor compared to the 21/23 method.
Objectives: To compare the 21/23 method to topographical measurements.
Methods: 100 ASA physical status I-II patients scheduled for elective surgery were enrolled. The 21/23 method was initially utilized for intubation and the ETT tip to carina distance was then fiberoptically measured. Anatomical (topographical) measurements were then obtained from each patient by adding the distance from the corner of the mouth to the mandibular angle to the distance from the mandibular angle to the center of the sternal notch and were recorded as the topographical intubation depth. Both measurements were assessed for percentage of ETTs that fell outside of our desired tip to carina range of 2-4 cm.
Results: After the 21/23 method, 29% of ETTs fell outside our desired tip to carina range compared to 47% of ETTs with the topographical method (p=0.010). No correlation was found between the topographical measurements and airway length (upper incisors to vocal cords) (r=0.248).
Conclusions: Topographical measurements were not re-confirmed as an accurate intubation method and were found to be less reliable than the 21/23 method. We maintain that regardless of ETT insertion method utilized, the gold standard to ensure accurate ETT placement is fiberoptic inspection.
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References
Griesdale, Donald E. G., T. Laine Bosma, Tobias Kurth, George Isac, and Dean R. Chittock. "Complications of Endotracheal Intubation in the Critically Ill." Intensive Care Medicine 34.10 (2008): 1835-842
Dronen S, Chadwick O, Nowak R: Endotracheal tip position in the arrested patient (letter). Ann Emerg Med 1982; 11:116-17.
Owen RL, and FW Cheney. Endobronchial Intubation: A Preventable Complication. Anesthesiology 1987; 67:255-57.
Ong, K. C, GD A'Court, P Eng, YY Ong: Ideal Endotracheal Tube Placement by Referencing Measurements on the Tube. Ann Acad Med Singapore 1996; 25.4 :550-52.
Hwang JY, Rhee KY, Kim JH, YS Park, SH Han: Methods of Endotracheal Tube Placement in Patients Undergoing Pelviscopic Surgery. Anaesth Intensive Care 2007; 35.6: 953-56.
View more references (19)
Evron S, Weisenberg M, Harow E, Khazin V, Szmuk P, Gavish D, T Ezri: "Proper Insertion Depth of Endotracheal Tubes in Adults by Topographic Landmarks Measurements." Journal of Clinical Anesthesia 19.1 (2007): 15-19.
Dullenkopf A, Gerber A, Weiss M: Fluid leakage past tracheal tube cuffs: evaluation of the new Microcuff endotracheal tube. Intensive Care Med 2003; 29(10):1849-53.
Poelaert J, Depuydt P, De Wolf A, Van de Velde S, Herck I, Blot S: Polyurethane cuffed endotracheal tubes to prevent early postoperative pneumonia after cardiac surgery: a pilot study. J Thorac Cardiovasc Surg 2008; 135(4):771-76.
Miller MA, Arndt JL, Konkle MA, Chenoweth CE, Iwashyna TJ, Flaherty KR, Hyzy RC. A polyurethane cuffed endotracheal tube is associated with decreased rates of ventilator-associated pneumonia. J Crit Care. 2011 Jun;26(3):280-6. doi: 10.1016/j.jcrc.2010.05.035. Epub 2010 Jul 10.
Mangar D, Sprenker CJ, Karlnoski RA., Dodson R, Brashears B, Downes K, Camporesi EM. Migration of polyurethane high-volume low-pressure cuffed endotracheal tubes after neck flexion and extension. 2013 March. J of Anesth. [IN PRESS]
Ovassapian A: Fiberoptic airway endoscopy in critical care, Fiberoptic endoscopy and the difficult airway, 2nd edition. Philadelphia, Lippincott-Raven Publishers, 1996, pp 164-6.
Kim JT, Kim HJ, Ahn W, Kim HS, Bahk JH, Lee SC, Kim CS, SD Kim: Head Rotation, Flexion, and Extension Alter Endotracheal Tube Position in Adults and Children. Canadian Journal of Anesthesia 2009; 56.10 : 751-56.
Hartrey R, IG Kestin: Movement of Oral and Nasal Tracheal Tubes as a Result of Changes in Head and Neck Position. Anaesthesia 1995; 50.8: 682-87.
Roberts JR, Spadafora M, DC Cone: Proper Depth of Placement of Oral Endotracheal Tubes in Adults Prior to Radiographic Confirmation. Academic Emergency Medicine 1995; 2.1: 20-24.
Techanivate A, Kumwilaisak K, S Samranrean: Estimation of the Proper Length of Orotracheal Intubation by Chula Formula. J Med Assoc Thai 2005; 88.12: 1838-846.
Ong KC, GD A'Court, P Eng, YY Ong: Ideal Endotracheal Tube Placement by Referencing Measurements on the Tube. Ann Acad Med Singapore 1996; 25.4: 550-52.
Mehta, S: Intubation Guide Marks for Correct Tube Placement A Clinical Study. Anaesthesia 1991; 46.4: 306-08.
Hwang JY, KY Rhee, JH Kim, YS Park, SH Han: Methods of Endotracheal Tube Placement in Patients Undergoing Pelviscopic Surgery. Anaesth Intensive Care 2007; 35.6: 953-56.
Goldman JM, Armstrong J P, Vaught LE, LC Daniel: A New Method for Identifying the Depth of Insertion of Tracheal Tubes. Biomed Sci Instrum 1995; 31: 225-28.
Ellis DG, Jakymec A, Kaplan RM, Stewart RD, Freeman JA, Bleyaert A, PE Berkebile: Guided Orotracheal Intubation in the Operating Room Using a Lighted Stylet: A Comparison with Direct Laryngoscopic Technique. Anesthesiology 1986; 64.6: 823-26.
Patel N, Mahajan RP, and FR Ellis: Estimation of the Correct Length of Tracheal Tubes in Adults. Anaesthesia 1993; 48.1: 74-5.
Goodman LR. Conrardy PA, Laing F, MM Singer: Radiographic Evaluation of Endotracheal Tube Position." Am J Roentgenol 1976; 127: 433-4.
Cherng HC, Wong CS, Hsu CH, ST Ho: Airway length in adults: Estimation of the optimal endotracheal tube length for orotracheal intubation. Journal of Clinical Anesthesia, 2002; 14(4), 271-4.
Cheney FW. A caution of the use of Routine Depth of insertion of Endotracheal Tubes (Letter). Anesthesiology 1991;74:961-962.