Real-time ultrasound guidance for percutaneous tracheostomy
Venkatakrishna Rajajee, University of Michigan
14 April 2011
We would like to thank Drs. Tremblay and Scales for their thoughtful commentary on our feasibility study of real-time ultrasound guidance for percutaneous tracheostomy (PT). We agree wholeheartedly with their assessment that further study is required to clarify the benefits of this procedure. We would, however, like to address two specific issues that were raised in the commentary-
1. While actual indentation of the anterior tracheal wall was visible only in 4/13 cases in our series, the needle path was traceable up to the anterior tracheal wall in all 13 patients. The lack of indentation, in our opinion, does not reflect an inability to track to the point of penetration; rather, as is frequently seen during direct bronchoscopic visualization of tracheal puncture, the needle is generally able to penetrate the trachea without causing gross deformation of the entire anterior tracheal wall. The instances when anterior tracheal indentation is noticed, we believe, reflect times that the needle pushes down on tracheal cartilage before slipping into the inter-tracheal ring space. We therefore firmly believe that our series does demonstrate the feasibility of tracking the needle to the point of penetration using real-time guidance in the vast-majority of, if not all, patients.
2. While we entirely agree that "routinely inserting tracheostomy tubes between tracheal rings lying low in the neck" is undesirable because of the risk of tracheo-innominate fistula, it should be noted that no specific evidence exists that placement of the guidewire immediately below the 4th tracheal ring- the lowest level used in our study- in the adult patient confers any greater risk for a tracheo-innominate fistua than insertion below the second or third ring. This is particularly true when the ultrasound can be used to assess the point of insertion and its proximity to the innominate artery and the thorax, allowing puncture below the 4th ring only if it is seated sufficiently high in the neck. Of note, the case reports referenced by the authors of the commentary refer to fistulas occurring with placement of the tube below the 8th tracheal ring.
Again, we would like to thank Drs. Tremblay and Scales for their careful analysis and commentary on this topic.
Critical Care
Real-time ultrasound guidance for percutaneous tracheostomy
14 April 2011
We would like to thank Drs. Tremblay and Scales for their thoughtful commentary on our feasibility study of real-time ultrasound guidance for percutaneous tracheostomy (PT). We agree wholeheartedly with their assessment that further study is required to clarify the benefits of this procedure. We would, however, like to address two specific issues that were raised in the commentary-
1. While actual indentation of the anterior tracheal wall was visible only in 4/13 cases in our series, the needle path was traceable up to the anterior tracheal wall in all 13 patients. The lack of indentation, in our opinion, does not reflect an inability to track to the point of penetration; rather, as is frequently seen during direct bronchoscopic visualization of tracheal puncture, the needle is generally able to penetrate the trachea without causing gross deformation of the entire anterior tracheal wall. The instances when anterior tracheal indentation is noticed, we believe, reflect times that the needle pushes down on tracheal cartilage before slipping into the inter-tracheal ring space. We therefore firmly believe that our series does demonstrate the feasibility of tracking the needle to the point of penetration using real-time guidance in the vast-majority of, if not all, patients.
2. While we entirely agree that "routinely inserting tracheostomy tubes between tracheal rings lying low in the neck" is undesirable because of the risk of tracheo-innominate fistula, it should be noted that no specific evidence exists that placement of the guidewire immediately below the 4th tracheal ring- the lowest level used in our study- in the adult patient confers any greater risk for a tracheo-innominate fistua than insertion below the second or third ring. This is particularly true when the ultrasound can be used to assess the point of insertion and its proximity to the innominate artery and the thorax, allowing puncture below the 4th ring only if it is seated sufficiently high in the neck. Of note, the case reports referenced by the authors of the commentary refer to fistulas occurring with placement of the tube below the 8th tracheal ring.
Again, we would like to thank Drs. Tremblay and Scales for their careful analysis and commentary on this topic.
- Rajajee V, Fletcher JJ, Rochlen LR, Jacobs TL
Competing interests
None