0
Editorials: POINT/COUNTERPOINT EDITORIALS |

Rebuttal From Dr HubmayrRebuttal from Dr Hubmayr

Rolf D. Hubmayr, MD, FCCP
Author and Funding Information

From the Division of Pulmonary and Critical Care Medicine, Department of Physiology and Biomedical Engineering, Mayo Clinic.

Correspondence to: Rolf D. Hubmayr, MD, FCCP, Division of Pulmonary and Critical Care Medicine, Mayo Clinic, 200 First St SW, Rochester, MN 55905; e-mail: rhubmayr@mayo.edu


Funding/Support: Dr Hubmayr receives grants from the Mayo Clinic and the National Institutes of Health [RO1 HL63178] in support of his research on mechanical ventilation-associated lung injury.

Financial/nonfinancial disclosures: The author has reported to CHEST that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.

Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (http://www.chestpubs.org/site/misc/reprints.xhtml).


© 2011 American College of Chest Physicians


Chest. 2011;140(1):14-15. doi:10.1378/chest.11-0826
Text Size: A A A
Published online

Extract

Now that Dr Gattinoni and I have had a chance to examine our respective arguments, it is obvious that the terms “low” and “all” were not specific enough attributes of tidal volume (Vt) and patients, respectively, on which to base our debate. Whereas I1 have focused on the merits of lowering Vt relative to historic norms for all patients, meaning even those without lung injury, Dr Gattinoni2 has emphasized that not all patients with injured lungs should get the same low Vt (ie, 6 mL/kg predicted body weight (PBW) as recommended by the ARDS Network).3 I could not agree more! Indeed, our group has recently put forth the very same argument.4 The only nuance on which Dr Gattinoni and I may differ relates to the “fuzziness” in the cause and effect relationship between strain, as defined by him, and lung injury.5 Whereas I favor the use of the Vt to total lung capacity (TLC) ratio (Vt/TLC) to quantify lung deformation, Dr Gattinoni favors strain, defined as the difference between the volume at end inspiration and that at zero end-expiratory pressure (VZEEP), normalized by VZEEP. Before I explain why I believe that my way of approaching the issue is more intuitive and useful, I want to underscore the shared premise, namely, that scaling Vt to the size of the injured lung is important. Predicted body weight scales with the size of the healthy lung (ie, the number of recruitable alveoli), but not with the capacity of a diseased lung. Given the large variability in disease-related unit drop-out, a “one size fits all” approach would expose the sickest patients, those with the “smallest lungs,” to the largest deforming stresses. Therefore, the size of the injured, as opposed to that of the healthy, lung needs to be considered when arriving at patient-protective ventilator settings. One way of doing so is to measure VZEEP using a gas dilution method, as proposed by Chiumello et al.6 How this information is used is where Dr Gattinoni and I differ.

First Page Preview

View Large
First page PDF preview

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Figures

Tables

References

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Sign In to Access Full Content

MEMBER & INDIVIDUAL SUBSCRIBER

Want Access?

NEW TO CHEST?

Become a CHEST member and receive a FREE subscription as a benefit of membership.

Individuals can purchase this article on ScienceDirect.

Individuals can purchase a subscription to the journal.

Individuals can purchase a subscription to the journal or buy individual articles.

Learn more about membership or Purchase a Full Subscription.

INSTITUTIONAL ACCESS

Institutional access is now available through ScienceDirect and can be purchased at myelsevier.com.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Find Similar Articles
CHEST Journal Articles
PubMed Articles
Guidelines
  • CHEST Journal
    Print ISSN: 0012-3692
    Online ISSN: 1931-3543