A Comparison of the Best Place to Fix Endotracheal Tubes for Men and Women When Men and Women Are in the Same Height

Abstract

Background: Comparison of the tracheal tube depth over the same body height of men and women based upon intubation depth markings. Methods: Kashan University of Medical Sciences ethics committee approved the study and written informed consent was taken for each patient. Patients undergoing surgery requiring general anesthesia with oro-tracheal intubation were included in a prospective observational study. After induction of general anesthesia, the endotracheal tube was secured at the point at which the cuff was just below the vocal cord on laryngoscopy. Results: In a statistical study of 682 intubated patients which consisted of 499 women and 183 men, 28 cases of laryngoscopic view grade III and IV were excluded from the study. The measurement markings on the ETT at the level of right corner of the mouth were 20.65 ± 0.13 and 18.52 ± 0.08 for men and women respectively (CI 95%). Patient's height has a meaningful correlation with the measurement of the fixation point of the ETT. Pearson correlation coefficient between the securing point of the tube and height was 0.2 and 0.357 for men and women respectively. In most cases of men and women of the same height, Mann-Whitney U test rejected the hypothesis that the tube can be fixed in the particular point. Conclusions: In general, men are taller than women. Comparing the fixation depth of the tube, even when man and woman have the same body height, the endotracheal tube might be placed in a deeper level for men rather than women.

An observational study to determine whether alignment of endotracheal tube indicator line with the vocal cords results in appropriate depth of intubation

“…The standard method used to guide ETT insertion depth is an approximation of the indicator mark on the ETT to the vocal cords (6)(7)(8). However, this mark may be inappropriate as it is placed arbitrarily by manufacturers and does not cater for patients of all physical characteristics.…”

“…Our protocol was designed to study the intubation depth with the indicator band aligned to the vocal cords. Conventional laryngoscopy does not permit good visualization of the indicator band in patients with grade III and IV laryngoscope views (8,12). We performed tracheal intubation with height in females (r 2 = 0.359 and p = 0.0001) but not in males (Fig.…”

Ideal Length of Oral Endotracheal Tube for Critically Ill Intubated Patients in an Asian Population: Comparison to Current Western Standards

“…A few studies have also reported a significant correlation between the ETT length and the height of the patient [14-16]. Nafisi et al reported that even though men, in general, are taller than women and the ETT needs to be fixed deeper in them, the ETT might be placed deeper in men than women even when they have the same body height [17]. In our study, we observed that the relationship between the ETT depth and the patient's height is affected by gender, but it may not be of clinical importance except in very extreme cases (Figure 3).…”