ATS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Erkan Yildirim
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Yildirim, E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Yildirim, E.
Related Collections
Right arrow Lung - cancer

Ann Thorac Surg 2004;78:1133-1134
© 2004 The Society of Thoracic Surgeons

Correspondence

The importance of obstructed and unobstructed segments to be resected in predicting postoperative FEV1

Erkan Yildirim, MD, FETCS

Ankara Numune Education and Research Hospital, Department of Thoracic Surgery, Asagiovecler mh. 79 Sk 8/3, Dikmen Ankara 06406, Turkey

erseda{at}yahoo.com

To the Editor:

I have just read the article by Sekine and colleagues [1]. In the text, a modified formula for calculating the predicted postoperative (ppo) forced expiratory volume in 1 second (FEV1) after lobectomy on the basis of the following equation was offered:

where S is the number of resected bronchopulmonary segments [2]. For lobectomy there is a strong correlation between the postoperative FEV1 expressed as ppo FEV1 and the actual values when the calculation is made depending on the number of segments to be removed at lobectomy. The calculation needs to be modified if any segments are obstructed as in the following equation [3]:

where a is the number of obstructed segments to be resected and b is the number of unobstructed segments to be resected, these can easily be determined by bronchoscopy.

In the first formula, the calculated ppo FEV1 values are always less than the values calculated by the second formula because of the existence of obstructed segments. In both situations, the preoperative FEV1 values are the same. This distinction is very important for patients with borderline preoperative FEV1 values, as in chronic obstructive pulmonary disease (COPD) patients. Patients who are considered inoperable according to the first formula may indeed be in the operable group. For example, for a patient for whom left upper lobectomy is planned, a = 2 and b = 3. The preoperative FEV1 value is 1.6 L. According to the first formula, the ppo FEV1 is 1.184 L, whereas according to the second formula, ppo FEV1 is 1.318 L. The difference is 134 mL.

The obstructed segments that will be resected do not have any contribution to the preoperative FEV1. Therefore, only the unobstructed segments to be removed should be taken into account when calculating the ppo FEV1. As a result, the first formula does not reflect the real value of the preoperative FEV1.

In conclusion, the authors should check the appropriateness of the second formula, described previously, for calculating the ppo FEV1, for both their COPD and non-COPD patient groups. If the second formula were taken into account, there would be no need to create a new equation for predicting postoperative FEV1 to produce a higher coefficient of determination (R2) than the conventional one.

References

  1. Sekine Y, Iwata T, Chiyo M, et al. Minimal alteration of pulmonary function after lobectomy in lung cancer patients with chronic obstructive pulmonary disease. Ann Thorac Surg. 2003;76:356–361[Abstract/Free Full Text]
  2. Juhl B, Frost N. A comparison between measured and calculated changes in the lung functions after operation for pulmonary cancer. Acta Anaesthesiol Scand. 1975;57(Suppl):39–45
  3. British Thoracic Society and Society of Cardithoracic Surgeons of Great Britain and Ireland Working Party. Guidelines on the selection of patients with lung cancer for surgery. Thorax. 2001;56:89–108[Free Full Text]



This article has been cited by other articles:


Home page
 Eur. J. Cardiothorac. Surg.Home page
G. Varela, A. Brunelli, G. Rocco, R. Marasco, M. F. Jimenez, V. Sciarra, J. L. Aranda, and T. Gatani
Predicted versus observed FEV1 in the immediate postoperative period after pulmonary lobectomy.
Eur. J. Cardiothorac. Surg., October 1, 2006; 30(4): 644 - 648.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to Personal Folders
Right arrow Download to citation manager
Right arrow Author home page(s):
Erkan Yildirim
Right arrow Permission Requests
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Yildirim, E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Yildirim, E.
Related Collections
Right arrow Lung - cancer

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ANN THORAC SURG ASIAN CARDIOVASC THORAC ANN EUR J CARDIOTHORAC SURG
J THORAC CARDIOVASC SURG ICVTS ALL CTSNet JOURNALS