J Thorac Cardiovasc Surg 2008;135:1408
© 2008 The American Association for Thoracic Surgery
Does the method of lung preservation influence outcome after transplantation? An analysis of 681 consecutive procedures
Gabriel Thabut, MDa,
Yves Castier, MDb,
Hervé Mal, MDa
a Service de pneumologie B et transplantation pulmonaire, Hôpital Bichat et Faculté Paris 7, Paris, France
b Service de chirurgie thoracique et vasculaire, Hôpital Bichat et Université Paris 7, Paris, France
To the Editor:
We read with great interest the study by Ganesh and colleagues1
that compared various graft preservation methods in lung transplantation. The authors rigorously assessed the association between the lung preservation method and the posttransplant survival up to 3 years in a large cohort of patients; they failed to detect any association. However, we think that the way the graft ischemic time was calculated and included in the analysis may have biased the results. Graft ischemic time has been shown to be associated with survival after lung transplantation in several studies.2,3 In these studies, in case of double-lung transplantation, graft ischemic time was defined as the time from donor crossclamping to reperfusion of the second lung. In their study, Ganesh and colleagues considered ischemic time as the time from donor crossclamping to reperfusion of the first lung only. This could lead to incorrect adjustment. Second, we have found that the relationship between graft ischemic time and survival could be of exponential form, the graft ischemic time altering the survival of recipients only when it exceeds 4 to 6 hours.3 Unfortunately, the authors did not report on the distribution of graft ischemic time by the preservation method. Given the incidence of local donors in their cohort, we suspect that graft ischemic time was rather short in most patients. This point is essential, because the efficacy of different graft preservation solutions may prove similar for short graft ischemic times and different for longer ischemic times. We think that the analysis of adjusted survival by preservation solution for patients with a long ischemic time would have yielded more insight in the efficacy of preservation solutions. However, the number of patients in each group would have probably been low, precluding powerful statistical analysis. The authors report no interaction between the graft ischemic time and the preservation solution used; however, interaction testing is not powerful enough. We agree that the way to definitely answer this question is to conduct a randomized controlled trial, and we think that such a trial should stratify patients by the expected graft ischemic time or the surgical procedure (single vs bilateral lung transplantation).
References
- Ganesh JS, Rogers CA, Banner NR, Bonser RS. Does the method of lung preservation influence outcome after transplantation? An analysis of 681 consecutive procedures. J Thorac Cardiovasc Surg 2007;134:1313-1321.[Abstract/Free Full Text]
- Novick RJ, Bennett LE, Meyer DM, Hosenpud JD. Influence of graft ischemic time and donor age on survival after lung transplantation. J Heart Lung Transplant 1999;18:425-431.[Medline]
- Thabut G, Mal H, Cerrina J, Dartevelle P, Dromer C, Velly JF, et al. Graft ischemic time and outcome of lung transplantation: a multicenter analysis. Am J Respir Crit Care Med 2005;171:786-791.[Abstract/Free Full Text]
