Evaluation of the risk of intercostal artery laceration during thoracentesis in elderly patients by using 3D-CT angiography.

OBJECTIVE: Our study was undertaken to determine the location of the tortuous intercostal artery in elderly patients by using 3D-CT angiography in order to prevent laceration during thoracentesis.

METHODS: We evaluated the data of 3D-CT angiography of the intercostal artery in consecutive patients who had undergone contrast chest CT scan in our hospital from December 2007 to April 2008. We considered the "percent safe space" (the shortest lower rib-to-intercostal artery distance/the upper rib-to-lower rib distance) to be an index of safety that can be used to prevent laceration of the intercostal artery during thoracentesis. We measured this index at 3 points: the total site (5-10 cm lateral to the spine), the lateral site (9-10 cm lateral to the spine), and the medial site (5-6 cm lateral to the spine).

RESULTS: We evaluated 33 cases (25 males and 8 females; mean age, 74.2 years). The mean percent safe space at the total site was 58.6%. The percent safe space at the total site tended to decrease with advancing age, but the correlation was low (p=0.0378, r=-0.3631). The percent safe space at the lateral site (mean, 79.8%) was significantly higher than that at the medial site (61.2%, p<0.0001).

CONCLUSION: We showed that the intercostal artery is tortuous and does not always lie along the inferior edge of the rib and that the percent safe space at the lateral site is significantly higher than that at the medial site in elderly patients.