Table 1 Description of measurements

Width of the ICS

Bottom edge of the 4th rib to the top edge of the 5th rib, measured in the coronar plane.

Difference between width of the ICS and outer diameter of the needles

(Width of the ICS in cm) – (outer diameter of the respective needle in cm).

Chest wall thickness

Distance from the skin surface to the pleural cavity, measured perpendicular to the chest wall in the axial plane.

Depth to vital structure

Distance from the skin surface to the intersection with the closest vital structure in the direction of puncture. Measured in the axial plane.

Decompression failure

Chest wall thickness > length of the needle

Risk of injury

Depth to vital structure < length of the needle

Vital structures

Pericardium, aorta, vena cava inferior and superior, pulmonary vessels including larger intraparenchymal branches, thymus gland.