Table 1 Age wise dimensions of the airways as by Szelloe et al. (Inoue, 1982), in comparison with calculated size of ETT
Age (years) | Smallest mean anteroposterior tracheal diameter (millimetres) | Mean right bronchial diameter (millimetres) | Mean left bronchial diameter (millimetres) | Predicted size of cuffed endotracheal tube = [3.5 + age (years)/4] (millimetres) |
|---|---|---|---|---|
0–1 | 6.0(2.9–7.7) | 3.9(2.4–6.0) | 3.4(2.1–5.7) | 3.5 |
1–2 | 7.0(4.3–9.2) | 4.9(3.8–7.5) | 4.2(2.7–6.6) | 4.0 |
2–4 | 7.9(4.1–10.3) | 6.1(3.0–7.9) | 5.5(2.7–8.5) | 4–4.5 |
4–6 | 7.5 (5.1–10.9) | 6.1(4.4–7.8) | 5.3(4.1–6.6) | 4.5–5.0 |
6–8 | 8.8(5.7–11.0) | 6.8(4.3–9.0) | 6.0(4.5–10.1) | 5.0–5.5 |
8–10 | 9.5(7.4–12) | 7.0(5.5–9.4) | 6.6(4.9–9.1) | 5.5–6.0 |
10–12 | 10.8(10.2–15.8) | 8.2(6.6–10.0) | 7.5(5.6–11.1) | 6.0–6.5 |
12–14 | 11.7(10.3–15.8) | 8.5(7.3–10.5) | 8.1(6.5–10.0) | 6.5–7 |
14–16 | 13.0(8.9–16.8) | 9.8(6.5–12.7) | 9.2(6.2–11.5) | 7–7.5 |