Tuesday April 29 , 2008
Carina as a Radiographic Landmark for Positioning the IABP

There are reports in literature that targeting tip of Intraaortic Balloon Pump (IABP) just below the aortic knob on CXR radiologically may still cause occlusion of left subclavian artery (upto 7 - 16%). 1,2.

See this interesting another approach to target carina as a Useful Radiographic Landmark for Positioning the Intraaortic Balloon Pump.

METHODS: The distance from the top of the distal aortic arch (aortic knob) to the left subclavian artery (LSCA) on three-dimensional computed tomography angiography in 100 patients, was measured. The distance from the level of the LSCA origin to the level of the carina was also measured using three-dimensional computed tomography in 150 additional patients.

RESULTS: In 16% of the aortic knob study population, the LSCA to aortic knob distance was <0 cm or 0 cm. The median distance from the LSCA to the carina was 42 mm (range: 30–63 mm). In the carina study population, the origin of the LSCA was 35–55 mm above the carina in 95.3% of patients.


CONCLUSION:

In 16% of patients, the IABP was too close to the LSCA origin when it was placed at the aortic knob, whereas Positioning the IABP at 2 cm above the carina provided an adequate position for the IABP tip (1.5–3.5 cm distal to the origin of the LSCA) in 95.3% of patients.

The carina may be a more reliable landmark for positioning the IABP than the aortic knob.



Reference: click to get abstract / article

1. AORTIC KNOB; CAN BE A RELIABLE RADIOGRAPHIC LANDMARK FOR PLACEMENT OF INTRA-AORTIC BALLOON PUMP TIP? - Canadian Journal of Anesthesia 53:26056 (2006)

2. The Carina as a Useful Radiographic Landmark for Positioning the Intraaortic Balloon Pump - Anesth Analg 2007;105:735-738