Invited commentary

Abstract

Dr Brunelli and colleagues have presented another important study on the common problem of air leaks. This trial is well designed, performed, analyzed, and written. On the surface, their findings seem to be contrary to the ones Marshall and we have reported. However careful scrutiny of Brunelli's data actually shows that it may support the findings in those previous prospective studies. The management of chest tubes is only one way to manage air leaks. Intra-operative preventative measures rather than post-operative management are always more important for any post-operative complication. Some intra-operative techniques include: fissure-less surgery, sealants, buttressing of staple lines, pneumoperitoneum, and pleural tents. Although chest tube management is important in patients with an air leak, the advantage of one chest tube setting over another becomes weakened when air leaks are small. In this study the authors have nicely shown that when a pleural tent is used, the setting of the chest tube makes little difference. This is of little surprise. Unfortunately, the previously reported classification of air leaks and an air leak meter were not used in this study, but the natural history of the leaks in this series suggests that many were small. When one eliminates the patients who had pleural tents, which the authors essentially do for us in Table 4, their own data begin to show the advantages of water seal. The numbers may be too small to show a statistically significant difference but the air leak duration was 5.4 days compared with 7.0 days and the “air leak days/cm of staple line” was only 0.08 compared with 0.12, both favoring the water seal group. Thus, perhaps a better title for this paper may be “Pleural Tents After Upper Lobectomy Negate the Advantages of Placing Chest Tubes on Water Seal.” This finding is also not unexpected because this group has already shown the advantage of a pleural tent after upper lobectomy in a very well done prospective randomized study that was recently published. Finally, why do the authors choose to use water seal in patients who had no air leak and were excluded in this study? We prefer suction in these patients since water seal seems to offer no real advantage. Furthermore, I am perplexed as to why they conclude the paper with the statement: “Based on the results of this analysis our current practice is to use moderate suction (−10 cm H2O) overnight and water seal during the day.” The authors never even studied −10 cm of suction and found no advantage to water seal and potential harm. Why is this now their preferred protocol? We are indebted to Dr Brunelli and colleagues for once again heightening our awareness of the problem of air leaks and for a well-done prospective randomized study. Perhaps more studies are needed to examine patients who undergo lobectomy only. Their finding that water seal may lead to increased complications is provocative. It would be easy to do a prospective randomized trial that only studied patients who underwent lobectomy and to recruit enough patients in the study so one could generate the statistical power needed to fully assess the advantages and disadvantages of water seal versus suction [1Marshall M.B Deeb M.E Bleier J.I.S Suction versus water seal after pulmonary resection, a randomized prospective study.Chest. 2002; 121: 831-835Crossref PubMed Scopus (139) Google Scholar, 2Cerfolio R.J Bass C Katholi C.R A prospective randomized trial compares suction versus water seal for air leaks.Ann Thorac Surg. 2001; 71: 1613-1617Abstract Full Text Full Text PDF PubMed Scopus (207) Google Scholar, 3Brunelli A Al Rafai M Monteverde M Borri A Salati M Pleural tent after upper lobectomy a randomized study of efficacy and duration of effect.Ann Thorac Surg. 2002; 74: 1958-1962Abstract Full Text Full Text PDF PubMed Scopus (58) Google Scholar].