I would like to thank Mourisse et al.1
for their comments on my recent editorial. It was not my intention to review the properties of each endobronchial blocker but rather to encourage all anesthesiologists to become familiar with the use of these devices as an alternative to a double-lumen tube (DLT). I appreciate Mourisse et al.
’s support of this concept.
The first issue raised by Mourisse et al.
is the feasibility of suctioning through the lumen of the EZ-blocker. I agree that it is more effective to suction through a DLT using a suction catheter because unlike an endobronchial blocker in position, the suction catheter can be advanced and withdrawn. However, the perception that thick secretions can be suctioned through a DLT can be misleading. Suctioning through a DLT is performed using a long 10-French catheter, which is provided in the DLT kit. Figure 1
shows the three 9-French endobronchial blockers (Arndt, Cohen, Uniblocker) and the 10-French suction catheter (provided in a 37-French DLT Mallinckrodt kit; Covidien, Mansfield, MA) in cross-section to show the sizes of the lumens. There is no appreciable difference among the sizes of the lumens. The EZ-blocker has a 7.0-French lumen divided in two, which practically reduces the lumen of each individual suction channel to a bare minimum. This makes it practically impossible to remove secretions when the EZ-blocker is used.
Deflating the endobronchial blocker cuff to allow passive deflation of the lung through the single-lumen tube is an option. However, that would expose the patient to the potential risks of contamination when the lung isolation is abolished.
Mourisse et al. comment that intermittent suctioning increases the risk of negative pressure pulmonary edema. Intermittent suctioning is the routine practice of many anesthesiologists and one that I have used in hundreds of patients without any complications. Surely, if the risk was significant, the literature would have been flooded with case reports of pulmonary edema.
With regard to the confusion concerning the low-volume, high-pressure cuff of the EZ-blocker, I like to thank the authors for the clarification. The occluding cuff pressure of the Cohen, Arndt, and the Uniblocker is between 30 and 40 cm H2
If the cuff of the EZ-blocker has a high pressure of 110 cm H2
O, I would advise caution when using the EZ-blocker for an extended time to avoid the risk of mucosal damage if the bronchial venous circulation is compromised.
No device is perfect. Anesthesiologists should be familiar with the advantages and the disadvantages of each device and select the one that is best for his/her patient.
Edmond Cohen, M.D.
, Icahn School of Medicine at Mount Sinai, New York, New York. firstname.lastname@example.org
1. Cohen E. Back to blockers? The continued search for the ideal endobronchial blocker. Anesthesiology. 2013;118:490–3
2. Roscoe A, Kanellakos GW, McRae K, Slinger PD. Pressure exerted by the endobronchial devices. Anesth Analg. 2007;104:655–8
© 2013 American Society of Anesthesiologists, Inc.