The carina (the point at which the trachea
divides into the right and left main bronchi)
usually lies at the level of the 4th or 5th
thoracic vertebrae, although it can vary
Sometimes the angle of the carina can be
very acute and in other patients the carina
may be splayed wider apart. The carina
can usually be seen on a standard chest
X-ray
The image to the right is taken from a CT
scan (in a patient without an NG tube) but
it illustrates the x-ray appearance of the
carina very clearly
When checking NG tube position the tube
should be seen to pass into the area
underneath the carina thereby "bisecting"
it
This does not mean the tube has to pass
precisely in the midline or divide the
carina into equal halves
The diagram on the next slide illustrates
this
