One-lung ventilation for thoracic surgery and occasionally also in critical care medicine represents one of the most challenging airway and ventilation management tasks for anesthesiologists and/or intensivists [
Strategies for the actual sizing vary from the “one size fits almost all” approach to selection of a DLT that most closely matches the patient’s airway anatomy with deflated cuffs [
However, the size selection of the outer diameter and length of a DLT remains challenging even with the availability of precise CT-based knowledge of individual anatomical dimensions. This is further complicated by the fact that the effective outer diameter of a DLT is indicated as circumference on the packaging as “French” (
It is the aim of this work to present a point of reference for the relevant dimensions of conventionally available DLTs.
Left-sided DLTs of the sizes 35 Fr, 37 Fr, 39 Fr, and 41 Fr from six different manufacturers were included in this in vitro study (Table
Investigated left-sided double-lumen endobronchial tubes (sizes 35 F, 37 F, 39 F, and 41 F).
Brand | Manufacturer |
---|---|
Hudson RCI® Sheridan® SHER-I-BRONCH® endobronchial tube | Teleflex, Athlone, Ireland |
Mallinckrodt® endobronchial tube | Covidien, Tullamore, Ireland |
Portex Blue Line® endobronchial tube | Smiths Medical, Hythe, UK |
Rüsch Bronchopart® | Teleflex, Athlone, Ireland |
VIVASIGHT-DL® | ETView Medical, Misgav, Israel |
Well Lead® endobronchial tube | Well Lead Medical, Panyu, China |
One brand new DLT of each type and size was measured twice by two investigators (NH and SS), i.e., four measurements of each dimensional parameter were taken. The investigators were performing their measurements independently and not knowing about the results obtained by their counterpart. Dimensions of the tube (diameter and length), cuff (diameter and length), and the angle of the endobronchial tube portion were determined (Figure
Schematic of localization of measured parameters. A = beginning of the DLT shaft. B = midpoint between the beginning of the shaft of the tube (A) and the proximal edge of the tracheal cuff (C). C = proximal edge of the tracheal cuff. D = distal edge of the tracheal cuff. E = proximal edge of the bronchial cuff. F = distal edge of the bronchial cuff. H = virtual extrapolated longitudinal line through the middle of the tracheal tube shaft. I = virtual extrapolated longitudinal line through bronchial tube shaft.
The following dimensional parameters of the DLT were measured or calculated (Figure Outer tube diameter (OD, always both: lateral and anterior-posterior) is as follows: ODMIDDLE = diameter in the center (B) between the beginning of the shaft of the tube (A) and the proximal edge of the tracheal cuff (C) ODPTC = diameter directly at the proximal edge of the tracheal cuff (C) ODDTC = diameter directly at the distal edge of the tracheal cuff (D) ODPBC = diameter directly at the proximal edge of the bronchial cuff (E) ODDBC = diameter directly at the distal edge of the bronchial cuff (F) Internal tube diameter (ID): The tracheal and endobronchial lumen of all investigated DLTs were assessed for passability of a fiber-optic bronchoscope (Karl Storz, Germany) with diameters 5.5 mm and 4.0 mm, respectively. Lengths are as follows: Length A–C = distance from beginning of DLT shaft (A) to the proximal edge of the tracheal cuff (C) Length C-D = length of the tracheal cuff Length D-E = distance from the distal edge of the tracheal cuff (D) to the proximal edge of the bronchial cuffs (E) Length E-F = length of the bronchial cuff Length F-G = distance from the distal edge of the bronchial cuffs (F) to the tip of the tube (G) Length A–G = tube length from bifurcation (A) to the tip of the tube (G) Outer cuff diameters: outer cuff diameters were assessed with the cuffs not being in contact with a model of tracheal/bronchial lining. For the measurement of the tracheal and bronchial cuff diameters, the respective cuff inflation line was connected via a three-way stopcock to the manual cuff pressure gauge and inflated with air to the target pressure of 20 H2O using a 10 ml syringe. Upon reaching the target pressure, the three-way stopcock was closed so that no air could escape. The volume of air necessary to generate the target pressure of 20 H2O was noted. Angle is as follows: Angle H-I = mediastinal angle between a virtual longitudinal line through the middle of the tube shaft and the bronchial tube section
Since DLTs rarely present with a truly round cross-sectional area but are rather elliptically shaped, the cross-sectional area (CSA) was calculated at the points indicated below, utilizing the measured width and height of the tube according to the formula CSAMIDDLE = cross-sectional area of the endobronchial tube in the middle (B) between the beginning of the tube shaft (A) and the proximal edge of the tracheal cuff (C) CSAPTC = cross-sectional area of the endobronchial tube directly at the proximal edge of the tracheal cuff (C) CSADTC = cross-sectional area of the endobronchial tube directly at the distal edge of the tracheal cuff (D) CSAPBC = cross-sectional area of the endobronchial tube directly at the proximal edge of the bronchial cuff (E) CSADBC = cross-sectional area of the endobronchial tube directly at the distal edge of the bronchial cuff (F)
For all DLTs investigated, it was noted whether the package insert provides information on the abovementioned parameters besides the nominal tube size given in French (1/3 mm).
Descriptive statistics were used to compare measured data. All data are presented as median (minimum-maximum). The analysis was performed using Microsoft Excel 2010 (Microsoft, Redmond, USA).
A total of 624 measured or calculated values were obtained from the 24 different DLTs.
Outer diameters measured and cross-sectional areas calculated are expressed in Tables
Outer diameter (OD), presented as lateral diameter (lat) und antero-posterior diameter (ap) of investigated left-sided double-lumen endobronchial tubes (DLT).
Parameter | Size (Fr) | Axis | Sheridan DLT | Mallinckrodt DLT | Portex DLT | Rüsch DLT | VIVASIGHT DLT | Well Lead DLT |
---|---|---|---|---|---|---|---|---|
ODMIDDLE | 35 | lat | 13.0 (13.0–13.3) | 12.7 (12.7–12.7) | 12.4 (12.4–12.7; |
12.5 (12.4–12.6) | 13.2 (12.9–13.5) | 12.9 (12.4–13.5) |
ap | 11.3 (11.0–11.5) | 11.7 (11.7–11.8) | 10.9 (10.8–11.0; |
11.0 (10.9–11.2) | 11.7 (11.6–11.9) | 11.6 (11.5–12.0) | ||
37 | lat | 13.0 (12.5–13.6; |
13.3 (13.3–13.5) | 13.3 (13.0–13.5) | 13.5 (13.0–13.8) | 13.4 (12.9–13.9) | 13.8 (13.6–14.0) | |
ap | 11.2 (10.1–11.5; |
12.7 (12.6–12.7) | 11.4 (11.2–11.5) | 11.4 (11.3–11.6) | 13.2 (12.7–13.8) | 13.1 (13.0–13.4) | ||
39 | lat | 14.4 (14.3–14.6) | 14.4 (14.4–14.5) | 13.7 (13.5–14.0) | 13.4 (12.8–14.0; |
14.3 (14.1–14.3) | 14.3 (14.0–14.7) | |
ap | 12.0 (11.9–12.2) | 13.5 (13.0–14.0) | 11.8 (11.8–11.9; |
12.5 (12.4–14.5) | 13.1 (13.1–13.2) | 13.6 (13.3–13.8) | ||
41 | lat | 14.5 (14.2–14.7) | 14.8 (14.7–14.9) | 14.5 (14.3–14.7; |
14.4 (14.3–14.7) | 15.0 (15.0–15.0) | 14.9 (14.8–15.0) | |
ap | 12.8 (12.7–12.8) | 13.8 (13.6–13.9) | 12.5 (12.3–12.6; |
13.0 (13.0–13.1) | 14.0 (14.0–14.0) | 14.0 (13.9–14.2) | ||
|
||||||||
ODPTC | 35 | lat | 13.7 (13.5–13.9) | 12.8 (12.7–12.8) | 12.8 (12.2–13.3) | 12.5 (12.3–12.6; |
13.5 (13.2–13.7) | 13.3 (13.0–13.5) |
ap | 11.8 (11.7–11.9) | 12.1 (12.1–12.1) | 11.6 (11.6–11.9; |
11.7 (11.6–11.7) | 12.5 (12.3–12.7) | 12.4 (12.1–13.0) | ||
37 | lat | 13.9 (13.5–14.3) | 13.4 (13.3–13.6; |
14.0 (13.6–14.0) | 13.8 (13.5–13.9) | 14.7 (14.6–15.0) | 14.2 (13.8–14.6) | |
ap | 12.0 (11.9–12.2; |
13.2 (13.1–13.2) | 12.0 (12.0–12.1; |
12.0 (11.9–12.0; |
13.7 (13.5–13.9) | 13.8 (13.4–14.3) | ||
39 | lat | 14.7 (14.4–15.0) | 14.2 (14.1–14.3) | 14.2 (13.9–14.7) | 13.9 (13.1–14.5; |
14.8 (14.7–14.9) | 14.8 (14.5–15.0) | |
ap | 12.7 (12.7–12.8; |
13.4 (13.4–13.5) | 12.7 (12.5–12.8; |
13.0 (12.9–13.1) | 14.3 (13.8–14.9) | 14.1 (13.8–14.7) | ||
41 | lat | 14.8 (14.5–15.0) | 14.9 (14.8–14.9) | 15.2 (15.0–15.5) | 14.7 (14.4–14.7; |
15.6 (15.5–16.1) | 15.6 (15.1–15.9) | |
ap | 13.5 (13.4–13.6) | 14.0 (14.0–14.1) | 13.3 (13.3–13.4; |
13.7 (13.6–13.7) | 14.6 (14.3–14.9) | 14.6 (14.6–14.7) | ||
|
||||||||
ODDTC | 35 | lat | 14.6 (14.2–14.9) | 12.9 (12.8–13.0; |
13.1 (12.8–13.2) | 13.1 (13.1–13.2) | 13.9 (13.8–14.1) | 13.4 (12.5–13.5) |
ap | 11.8 (11.8–12.0) | 12.1 (12.1–12.2) | 11.6 (11.6–12.1; |
11.6 (11.6–11.7; |
13.1 (12.8–13.5) | 12.5 (12.1–13.3) | ||
37 | lat | 13.6 (13.6–14.2; |
13.6 (13.6–13.8; |
13.6 (13.6–14.0; |
13.8 (13.4–14.0) | 14.6 (14.4–14.7) | 14.3 (14.1–14.5) | |
ap | 12.2 (12.1–12.3) | 13.2 (13.2–13.2) | 12.0 (11.9–12.2) | 11.9 (11.7–12.2; |
14.2 (13.8–14.7) | 13.9 (13.5–14.2) | ||
39 | lat | 14.8 (14.7–14.9) | 14.5 (14.4–14.6) | 14.3 (14.0–14.4; |
14.4 (14.2–14.6) | 14.8 (14.7–15.0) | 14.7 (14.4–15.0) | |
ap | 12.8 (12.8–12.9) | 13.4 (13.3–13.5) | 12.6 (12.6–12.7; |
12.9 (12.7–13.4) | 14.0 (13.9–14.4) | 14.0 (13.8–14.3) | ||
41 | lat | 15.3 (15.0–15.4) | 14.9 (14.8–15.0) | 15.1 (15.0–15.2) | 14.7 (14.6–14.7; |
15.4 (15.1–15.5) | 15.6 (15.3–15.6) | |
ap | 13.6 (13.5–13.7) | 14.0 (14.0–14.1) | 13.2 (13.1–13.6; |
13.5 (13.5–14.1) | 14.6 (14.5–14.7) | 14.5 (14.4–14.6) | ||
|
||||||||
ODPBC | 35 | lat | 8.8 (8.3–9.0) | 9.0 (8.9–9.1) | 7.8 (7.5–8.1; |
9.2 (9.1–9.3) | 9.0 (8.5–9.5) | 9.0 (8.7–9.1) |
ap | 10.8 (10.7–10.8) | 9.5 (9.4–9.7; |
10.7 (10.6–10.9) | 10.7 (10.5–10.9) | 10.4 (10.3–10.5) | 10.3 (10.2–10.6) | ||
37 | lat | 8.8 (8.5–9.1) | 10.0 (9.5–10.0) | 7.8 (7.7–8.0; |
9.3 (9.1–9.7) | 8.9 (8.8–9.0) | 9.8 (9.6–9.9) | |
ap | 11.1 (10.8–11.2) | 10.8 (10.7–11.0) | 10.9 (10.7–11.0) | 10.8 (10.7–11.2) | 10.7 (10.5–11.3; |
11.1 (11.0–11.2) | ||
39 | lat | 8.7 (8.5–9.0) | 10.4 (10.3–10.8) | 8.1 (7.8–8.4; |
10.4 (9.8–10.8) | 9.3 (8.9–9.7) | 9.7 (9.3–10.3) | |
ap | 11.3 (11.1–11.5) | 10.9 (10.8–11.1) | 11.7 (11.2–11.8) | 11.6 (11.4–11.7) | 10.8 (10.5–11.0; |
11.4 (11.0–12.0) | ||
41 | lat | 8.9 (8.8–9.4) | 10.2 (10.1–10.4) | 8.8 (8.7–9.5; |
10.7 (10.0–11.1) | 9.1 (8.9–9.2) | 9.9 (9.2–10.0) | |
ap | 12.5 (12.2–12.7) | 11.2 (11.0–11.5) | 12.3 (12.2–12.4; |
12.1 (11.9–12.2) | 12.2 (12.1–12.3) | 11.7 (11.5–11.9) | ||
|
||||||||
ODDBC | 35 | lat | 9.0 (8.5–9.3) | 9.1 (9.1–9.2) | 8.4 (8.0–8.6; |
9.3 (9.1–9.7) | 9.4 (9.0–9.8) | 8.7 (8.4–9.1) |
ap | 11.2 (10.9–11.3) | 10.2 (10.1–10.3) | 9.9 (9.6–10.0; |
10.1 (9.5–11.0) | 11.0 (10.8–11.0) | 10.7 (10.3–10.9) | ||
37 | lat | 9.8 (9.7–10.0) | 10.0 (10.0–10.0) | 8.6 (8.5–8.7; |
9.9 (9.3–10.3) | 9.2 (9.1–9.6) | 9.9 (9.6–10.0) | |
ap | 11.4 (11.4–11.9) | 11.1 (11.0–11.3) | 10.0 (10.0–10.1; |
11.4 (10.6–11.5) | 11.4 (11.3–11.5) | 11.9 (11.6–12.0) | ||
39 | lat | 8.9 (8.7–9.0; |
10.5 (10.0–10.5) | 9.6 (9.2–9.7) | 10.2 (10.1–10.5) | 10.2 (10.0–10.3) | 10.7 (10.0–12.0) | |
ap | 11.7 (11.7–11.8) | 11.5 (11.0–11.6) | 11.4 (11.3–11.5) | 11.5 (10.9–11.8) | 11.3 (11.3–11.3) | 10.7 (9.7–11.8; |
||
41 | lat | 8.9 (8.7–9.2; |
10.6 (10.5–10.7) | 10.0 (9.9–10.0) | 10.6 (10.3–10.7) | 9.6 (9.2–9.7) | 10.2 (9.8–10.5) | |
ap | 12.8 (12.5–12.9) | 11.5 (11.4–11.7) | 11.3 (11.0–11.5; |
12.3 (12.0–12.6) | 12.0 (12.0–12.1) | 12.0 (12.0–12.3) |
ODMIDDLE = outer diameter in the middle (B) between the beginning of the DLT shaft (A) and the proximal edge of the tracheal cuff (C); ODPTC = outer diameter at the proximal edge of the tracheal cuff (C); ODDTC = outer diameter at the distal edge of the tracheal cuff (D); ODPBC = outer diameter at the proximal edge of the bronchial cuff (E); ODDBC = outer diameter at the distal edge of the bronchial cuff (F) (see also Figure
Calculated cross-sectional areas (CSAs) of investigated left-sided double-lumen endobronchial tubes (DLTs) based on measurements expressed in Table
Parameter | Size (Fr) | Sheridan DLT | Mallinckrodt DLT | Portex DLT | Rüsch DLT | VIVASIGHT DLT | Well Lead DLT |
---|---|---|---|---|---|---|---|
CSAMIDDLE | 35 | 114.9 (114.3–116.4) | 116.9 (116.6–117.1) | 105.4 (105.1–109.2; |
107.7 (107.1–109.5) | 121.3 (118.5–124.0) | 117.5 (111.9–126.7) |
37 | 114.7 (98.6–121.7; |
132.6 (132.1–132.6) | 118.0 (114.9–121.4) | 120.7 (118.4–123.6) | 138.9 (137.6–139.7) | 141.9 (138.3–145.2) | |
39 | 135.9 (133.6–138.3) | 152.3 (147.0–158.8) | 126.9 (124.5–130.8; |
131.7 (124.1–158.8) | 146.3 (145.0–148.2) | 152.0 (150.6–154.1) | |
41 | 144.4 (142.1–147.7) | 160.1 (158.0–160.4) | 140.8 (139.8–143.3; |
147.2 (145.4–149.5) | 164.9 (164.3–164.9) | 163.8 (162.6–164.4) | |
|
|||||||
CSAPTC | 35 | 126.7 (123.5–129.3) | 121.1 (120.6–121.6) | 118.0 (111.1–121.2) | 114.3 (112.5–115.7; |
132.2 (127.5–136.0) | 130.7 (125.4–132.2) |
37 | 130.7 (125.6–137.0) | 138.1 (136.3–140.4) | 131.7 (128.6–131.9) | 129.0 (126.6–130.4; |
158.1 (153.6–163.1) | 154.0 (151.1–156.5) | |
39 | 147.1 (143.0–149.5) | 148.8 (148.3–151.0) | 140.8 (137.4–146.6; |
141.5 (133.2–146.9) | 165.5 (159.2–173.7) | 162.9 (161.4–168.5) | |
41 | 156.5 (154.2–157.8; |
163.5 (163.2–163.8) | 158.7 (156.1–163.0) | 157.0 (154.3–158.1) | 179.7 (174.0–185.8) | 178.2 (171.9–182.3) | |
|
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CSADTC | 35 | 135.8 (133.8–137.4) | 122.6 (121.1–124.0) | 120.0 (116.6–124.0) | 119.5 (119.2–120.8; |
142.7 (138.6–149.4) | 129.4 (126.3–136.2) |
37 | 130.5 (128.2–136.6) | 141.2 (139.9–142.5) | 128.4 (127.0–130.8; |
128.9 (122.6–133.1) | 161.9 (158.7–166.7) | 155.7 (152.0–157.2) | |
39 | 148.8 (146.6–150.4) | 152.0 (149.8–154.2) | 141.2 (138.0–143.6; |
146.6 (141.6–151.5) | 162.1 (160.4–169.6) | 161.2 (160.0–162.5) | |
41 | 162.2 (158.4–165.0) | 164.1 (162.7–164.9) | 156.5 (154.3–161.1) | 156.1 (154.7–162.1; |
175.6 (173.7–177.6) | 177.0 (173.6–178.2) | |
|
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CSAPBC | 35 | 74.0 (69.4–76.3) | 67.1 (66.8–67.4) | 65.8 (63.3–68.0; |
77.4 (75.1–77.6) | 72.9 (68.4–78.3) | 72.2 (71.3–74.3) |
37 | 76.3 (73.3–78.9) | 84.2 (81.3–86.0) | 66.3 (65.5–68.6; |
79.5 (77.5–81.1) | 75.0 (72.5–77.6) | 85.4 (82.5–86.3) | |
39 | 76.7 (74.1–80.8) | 89.8 (86.9–92.8) | 73.9 (69.6–77.8; |
94.3 (87.3–98.7) | 78.0 (76.2–81.1) | 86.6 (79.9–96.6) | |
41 | 86.7 (83.5–93.3) | 90.0 (87.2–92.3) | 85.3 (83.5–90.5) | 101.0 (93.0–105.3) | 86.9 (85.6–87.6) | 89.8 (84.5–93.4) | |
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CSADBC | 35 | 78.3 (74.6–81.0) | 72.5 (71.4–73.6) | 64.3 (60.9–67.5; |
72.9 (68.6–83.4) | 80.7 (75.9–83.9) | 73.0 (67.9–76.4) |
37 | 88.6 (86.4–90.7) | 87.3 (86.4–88.3) | 67.6 (66.3–68.3; |
88.4 (77.4–93.0) | 81.9 (81.1–85.5) | 92.3 (87.0–93.3) | |
39 | 81.6 (79.1–82.7; |
94.4 (86.4–95.6) | 85.7 (82.2–86.4) | 91.7 (86.8–97.3) | 89.8 (88.7–90.9) | 91.0 (86.0–92.6) | |
41 | 88.6 (86.4–92.3) | 95.0 (93.5–97.8) | 87.7 (85.5–89.9; |
101.5 (97.4–105.8) | 90.2 (86.7–92.1) | 96.3 (94.2–98.0) |
CSAMIDDLE = cross-sectional area in the middle (B) between the beginning of the DLT shaft (A) and the proximal edge of the tracheal cuff (C); CSAPTC = cross-sectional area at the proximal edge of the tracheal cuff (C); CSADTC = cross-sectional area at the distal edge of the tracheal cuff (D); CSAPBC = cross-sectional area at the proximal edge of the bronchial cuff (E); CSADBC = cross-sectional area at the distal edge of the bronchial cuff (F) (see also Figure
For the majority of the DLT types and sizes examined, the respective CSA increased appropriately with increasing size of the DLT. But remarkably, in 4 constellations, the CSA of the next smaller DLT from the same manufacturer was larger than in its next larger size.
All endobronchial lumen were easily passable by using a fiberoptic bronchoscope with an ID of 4.0 mm, as were all tracheal lumen. Neither lumen of the DLTs sizes 35 and 37 was passable by using a fiberoptic bronchoscope with an ID of 5.5 mm. Passability with an ID 5.5 mm bronchoscope was given only for the tracheal lumen of the VIVASIGHT-DL® and both lumina of the Hudson RCI® Sheridan® SHER-I-BRONCH® Endobronchial Tube in size 39 Fr. In size 41 Fr DLTs, both lumina of the VIVASIGHT-DL® and the Well Lead® endobronchial tube were easily passable, as was the bronchial lumen of the Mallinckrodt® endobronchial tube. In the Hudson RCI® Sheridan® SHER-I-BRONCH® endobronchial tube and the Portex Blue Line® endobronchial tube, both lumina were tight fitting but passable, and neither lumen of the Rüsch Bronchopart® was passable with the ID 5.5 mm bronchoscope.
The length measurements varied more among the various manufacturers and DLT sizes than did the CSAs (Table
Measured length of investigated left-sided double-lumen endobronchial tubes (DLTs).
Parameter | Size (Fr) | Sheridan DLT | Mallinckrodt DLT | Portex DLT | Rüsch DLT | VIVASIGHT DLT | Well Lead DLT |
---|---|---|---|---|---|---|---|
A–C | 35 | 260.0 (254.0–261.0) | 253.0 (252.0–254.0) | 318.5 (315.0–322.0) | 210.0 (207.0–214.0; |
241.0 (235.0–247.0) | 250.0 (248.0–253.0) |
37 | 258.0 (256.0–261.0) | 250.5 (249.0–252.0) | 317.5 (316.0–319.0) | 215.0 (214.0–215.0; |
241.0 (241.0–243.0) | 252.5 (248.0–256.0) | |
39 | 263.0 (262.0–263.0) | 248.0 (247.0–248.5) | 307.5 (304.0–308.0) | 234.5 (233.0–236.0; |
241.0 (238.0–243.0) | 251.0 (246.0–256.0) | |
41 | 264.5 (264.0–265.0) | 249.5 (247.0–251.0) | 304.5 (301.0–308.0) | 235.0 (234.0–236.0; |
242.0 (239.0–246.0) | 243.0 (239.0–247.0) | |
|
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C-D | 35 | 37.3 (36.0–40.0) | 40.0 (40.0–40.0) | 32.0 (32.0–32.8; |
36.3 (36.0–37.0) | 44.0 (43.7–44.3) | 44.0 (43.0–45.0) |
37 | 36.8 (35.5–38.0; |
43.0 (42.0–43.5) | 38.1 (37.0–39.0) | 37.0 (35.0–39.5) | 41.9 (41.7–43.0) | 43.0 (42.0–44.0) | |
39 | 38.3 (38.0–39.0) | 43.0 (42.0–44.0) | 39.0 (37.0–42.0) | 37.5 (36.5–39.0; |
45.2 (45.0–45.5) | 42.0 (41.0–42.5) | |
41 | 38.0 (37.0–40.0; |
39.0 (38.0–39.1) | 42.9 (41.0–44.0) | 38.1 (38.0–39.0) | 44.2 (43.3–46.0) | 42.3 (42.0–43.0) | |
|
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D-E | 35 | 38.0 (36.0–40.0) | 35.0 (35.0–35.0) | 40.0 (39.0–41.0) | 34.5 (31.0–38.0: |
36.5 (35.6–37.0) | 44.5 (39.0–48.0) |
37 | 43.5 (42.0–45.0) | 34.3 (34.0–35.0; |
39.5 (37.0–42.0) | 40.5 (39.0–41.0) | 40.8 (40.0–41.0) | 42.5 (38.0–46.0) | |
39 | 48.0 (45.0–51.0) | 40.0 (38.5–42.0) | 38.5 (35.0–41.0; |
42.0 (40.0–43.0) | 39.0 (37.0–40.3) | 44.5 (40.0–48.0) | |
41 | 42.0 (38.0–45.0) | 47.0 (44.0–49.0) | 39.0 (36.0–42.0; |
52.0 (51.0–53.0) | 40.3 (39.0–41.8) | 51.5 (51.0–52.0) | |
|
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E-F | 35 | 23.0 (23.0–23.5) | 16.8 (16.5–17.0) | 24.5 (23.0–25.3) | 17.4 (16.0–18.3) | 14.9 (14.3–15.0; |
15.7 (15.4–16.1) |
37 | 22.5 (22.0–23.0) | 19.5 (19.0–20.0) | 25.4 (24.8–27.0) | 16.6 (16.0–18.0) | 17.1 (17.0–17.6) | 15.9 (15.1–16.5; |
|
39 | 18.0 (18.0–18.3) | 18.5 (17.5–19.0) | 30.0 (30.0–30.3) | 19.0 (18.0–19.0) | 17.3 (16.0–17.6) | 15.8 (15.0–16.0; |
|
41 | 21.5 (21.0–22.0) | 17.1 (17.0–18.0) | 30.8 (30.0–31.0) | 16.5 (16.3–17.0) | 17.1 (17.0–17.5) | 15.6 (15.0–16.1; |
|
|
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F-G | 35 | 8.1 (7.0–9.5) | 11.1 (10.9–11.3) | 4.6 (4.0–5.7; |
6.0 (5.0–6.5) | 16.4 (15.5–17.0) | 11.2 (10.3–11.5) |
37 | 8.0 (7.3–8.1) | 12.0 (11.5–12.1) | 4.8 (4.5–4.8; |
7.1 (6.0–7.6) | 14.9 (12.5–18.0) | 12.0 (11.9–12.7) | |
39 | 10.0 (9.5–10.0) | 11.7 (11.1–11.9) | 6.6 (6.3–6.8) | 6.0 (5.0–6.1; |
13.1 (12.9–14.0) | 10.6 (10.5–11.0) | |
41 | 8.6 (8.0–9.0) | 14.2 (14.0–14.4) | 7.0 (6.8–7.5; |
7.5 (7.0–8.0) | 14.6 (14.0–15.0) | 10.5 (10.0–11.7) | |
|
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A–G | 35 | 366.4 (356.0–374.0) | 355.9 (354.4–357.3) | 419.6 (413.0–426.7) | 304.1 (295.0–313.8; |
352.7 (344.1–360.3) | 365.4 (355.6–373.6) |
37 | 368.8 (362.8–375.1) | 359.3 (355.5–362.6) | 425.3 (419.3–431.8) | 316.2 (310.0–321.1; |
355.6 (352.1–362.6) | 365.9 (355.0–375.2) | |
39 | 377.3 (372.5–381.3) | 361.2 (356.1–365.4) | 421.6 (412.3–428.0) | 339.0 (332.5–343.1; |
355.5 (348.9–360.4) | 363.8 (352.5–373.5) | |
41 | 374.6 (368.0–381.0) | 366.8 (360.0–371.5) | 424.1 (414.8–432.5) | 349.1 (346.3–353.0; |
358.2 (352.3–366.3) | 362.8 (357.0–369.8) |
A–C = distance from bifurcation (beginning of DLT shaft, A) to the proximal edge of the tracheal cuff (C); C-D = length of the tracheal cuff; D-E = distance between distal edge of the tracheal cuff (D) to the proximal edge of the bronchial Cuffs (E); E-F = length of the bronchial cuff; F-G = distance between the distal edge of the bronchial Cuffs (F) to the tip of the tube (G); A–G = tube length from bifurcation (A) to the tip of the tube (G) (see also Figure
Tracheal cuff dimensions revealed the largest variations in OD for a given DLT size of 72% (smallest to largest) for tracheal cuffs and 54% for bronchial cuffs (41 Fr) (Table
Tracheal and bronchial outer cuff diameters of the investigated left-sided double-lumen endobronchial tubes (DLTs) measured at a cuff pressure of 20 cm H2O.
Parameter | Size (Fr) | Sheridan DLT | Mallinckrodt DLT | Portex DLT | Rüsch DLT | VIVASIGHT DLT | Well Lead DLT |
---|---|---|---|---|---|---|---|
Tracheal cuff | 35 | 23.4 (23.3–23.7; |
24.3 (24.3–24.3) | 28.5 (28.3–29.2) | 27.6 (26.9–28.4) | 28.3 (27.9–28.6) | 29.7 (29.0–30.2) |
37 | 25.9 (25.7–26.3) | 25.0 (24.1–26.4; |
32.1 (31.7–32.7) | 27.0 (26.7–27.4) | 28.6 (27.9–29.3) | 28.9 (27.7–29.0) | |
39 | 24.9 (24.4–25.0; |
26.3 (26.2–26.5) | 32.2 (31.9–33.0) | 28.6 (27.3–29.6) | 28.8 (28.7–29.1) | 29.6 (28.7–30.1) | |
41 | 24.7 (24.5–24.9; |
25.6 (25.0–26.0) | 34.2 (33.3–34.4) | 27.1 (27.0–28.0) | 29.3 (29.1–29.6) | 30.5 (29.7–31.0) | |
|
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Bronchial cuff | 35 | 19.3 (19.0–19.8) | 20.6 (20.4–20.8) | 19.6 (19.3–20.2) | 13.5 (12.5–14.4; |
18.2 (17.6–18.7) | 18.6 (18.4–19.2) |
37 | 19.1 (18.9–20.1) | 20.3 (19.5–21.0) | 20.2 (19.5–20.7) | 13.8 (13.4–14.4; |
17.2 (16.4–18.2) | 19.2 (17.9–19.7) | |
39 | 19.9 (19.8–20.1) | 19.4 (19.0–20.0) | 24.6 (24.0–26.0) | 16.7 (16.4–17.0; |
24.2 (19.0–28.8) | 18.8 (18.4–19.1) | |
41 | 18.2 (17.8–18.6) | 20.3 (20.0–20.9) | 26.0 (25.0–27.0) | 14.0 (13.6–14.5; |
18.7 (18.2–19.2) | 19.1 (18.8–19.4) |
DLT sizes are in French (= 1/3 mm). Data are displayed as median (minimum-maximum) given as millimeter (mm). The largest cuff diameter of a respective DLT size is shaded in gray (100%), and the smallest diameter is marked with an asterisk (
The most impressive and surprising variation was that of the measured angle between the DLT shaft and the bronchial portion (Table
Measured angles of the investigated left-sided double-lumen endobronchial tubes (DLTs) between a virtual longitudinal line through the middle of the tracheal tube shaft and bronchial tube (see also Figure
Parameter | Size (Fr) | Sheridan DLT | Mallinckrodt DLT | Portex DLT | Rüsch DLT | VIVASIGHT DLT | Well Lead DLT |
---|---|---|---|---|---|---|---|
Angle | 35 | 39 (35–40) | 12 (12–12) | 40 (37–46) | 34 (32–34) | 26 (25–27) | 37 (36–40) |
37 | 28 (26–32) | 20 (18–22) | 39 (34–42) | 28 (27–30) | 24 (23–24) | 35 (34–36) | |
39 | 26 (22–29) | 18 (18–20) | 39 (36–43) | 27 (24–28) | 43 (40–47) | 35 (34–36) | |
41 | 31 (29–34) | 27 (25–28) | 37 (36–38) | 30 (28–32) | 46 (42–51) | 38 (36–40) |
DLT sizes are in French (= 1/3 mm). Data is displayed as median (minimum-maximum) and dimension is degrees (°).
The package insert for the Portex Blue Line® DLT was the only one that included additional information regarding the DLT’s dimensions (tracheal and bronchial cuff diameter in the uninflated state).
This study investigated the dimensional design of left-sided double-lumen endobronchial tubes in frequently used DLT sizes produced by six different manufacturers, including the recently introduced VIVASIGHT® DLT.
The most important finding was that there is considerable variability in the majority of all measured parameters among similarly sized DLT brands. The reported parameters may assist in further studies about the question which size of a double-lumen endobronchial tube to use in a certain patient.
In this study, five commonly used conventional left-sided DLTs as well as the new VIVASIGHT® DLT were examined. The VIVASIGHT® includes an integrated video camera and illuminating system that provides assistance with tube placement and continuous visual surveillance during the procedure [
The parts of the airway most relevant for the tube size selection are the larynx and the main bronchi, with the trachea presenting less of a problem with regard to tube diameters. [
In contrast to conventional tracheal tubes, whose nominal size is defined by the internal diameter (with possibly varying outer diameters), the nominal size of endobronchial tubes, according to the International Organization for Standardization (ISO 16628), is defined by the outer diameter of the (tracheal) tube shaft. However, for anesthetists, it is not common knowledge where exactly on the tube shaft the diameter is taken.
In clinical practice, anesthetists or intensivists have learnt to live with these limitations for years, even though the problems associated with the use of (inappropriate) DLTs are considerable. Clayton-Smith et al. [
An important point to be mentioned is the large variability in the volume of air necessary to generate a cuff pressure of 20 cm H2O in both the bronchial and the tracheal cuff. The use of a cuff pressure manometer in clinical practice is therefore recommended.
A limitation of our investigation is the fact that we only measured one copy of each DLT size and manufacturer/model. Russell and Strong showed in a similar study in 2003 that even nominally identical DLTs of the same manufacturer and size can reveal considerable variation in their dimensions, especially in the bronchial segment [
Considerable dimensional differences among similarly sized DLTs from different manufacturers are present. Inconsistent proportionalities with increasing DLT size and incomplete declaration of relevant dimensions for individual DLTs can limit the proper selection of a suitable DLT for one-lung ventilation and should be made more easily available. The new DLT model VIVASIGHT® with an integrated camera has a considerably larger cross-sectional area compared to similarly sized DLT brands.
Cross-sectional area
Computed tomography
Double-lumen endobronchial tube
French (1/3 mm)
Internal diameter
Outer diameter
Charriere
French (1/3 mm)
International Organization for Standardization.
All data on which the conclusions of the manuscript rely are presented in the main paper.
MW is a medical consultant for Medicoplast GmbH (Illingen, Germany).
N. H. and S. S. performed the data acquisition and helped drafting the manuscript. J. E. and M. P. S. critically revised the manuscript and made substantial contributions to interpreting the data. M. W. and A. D. initiated the data acquisition, performed the data analysis, and drafted the manuscript. All authors read and approved the final manuscript. This work was funded by departmental resources only.
All measured double-lumen endobronchial tubes were provided free of charge by the corresponding Swiss distributor companies. This work was solely funded by resources of the submitting author’s institution. This work was funded by departmental resources only.