NEWS AND VIEWS
Lobar Lung Transplantation: Emerging Evidence for a Viable Option Norihisa Shigemura, MD PhD, Jay Bhama, MD, Christian Bermudez, MD, and Jonathan D’Cunha, MD PhD The field of lung transplantation has seen an exciting evolution recently, with novel approaches to increasing the number of organs available for patients with end-stage lung disease. We review 2 recent reports describing the approach of lobar lung transplant as a successful and viable option for those recipients who are challenged by size mismatch and clinical course decline while on the transplant waiting list. Semin Thoracic Surg 25:95–96 I 2013 Elsevier Inc. All rights reserved. Keywords: lobar lung transplantation, size matching, donor, lobectomy, primary graft dysfunction, ECMO With the implementation of the lung allocation score (LAS) system, the demographics of the recipients have shifted, with an increased number of critically ill patients being considered for transplantation.1 Many transplant centers have numerous patients with small chests on their list who await the uncommon suitable donor. LAS does not take into consideration the size matching between donor and recipient lungs, which has a direct effect on waiting-list mortality for patients who are shorter than average Americans and those with restrictive lung disease. According to the most recent United Network for Organ Sharing data, the short group recipients (below 160 cm tall) waited for approximately 54 days more than average people (mean 168 cm tall) and the tall group patients (above 176 cm tall) waited approximately 59 days less than average people. If the short patients with restrictive lung diseases who need the smaller lungs wait for their ideal size-matching donors, their window for transplant would be very limited (or nonexistent). More importantly, recent data have demonstrated that lung transplantation in patients with high LAS is associated with significantly decreased survival and increased complications compared with patients with low LAS, the trend of which is more noticeable in patients with restrictive lung diseases.2 Therefore, the option of a lobar lung transplant (LLT) is potentially viable for those patients who have smaller than Department of Cardiothoracic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania. Address reprint requests to Norihisa Shigemura, MD, PhD, UPMC Presbyterian, Suite C-900, 200 Lothrop St, Pittsburgh, Pennsylvania 15213. E-mail: [email protected]
1043-0679/$-see front matter ª 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1053/j.semtcvs.2013.06.001
average chest cavities and restrictive lung disease because LLT can circumvent the issue of difficult organ availability, leading to potentially fewer cases of waiting-list mortality. This would hopefully translate into better transplant outcomes by transplanting at an earlier stage before a precipitous decline in the clinical course is encountered. Historically, the first report of LLT was described by a French group in 1994.3 Since then, this surgical option has been well addressed in a couple of reports by European and Australian groups4,5; however, interestingly, LLT has not yet been reported by the lung transplant centers in the United States. The report most recently published by a Swedish group demonstrated that the short- and long-term transplant outcomes after bilateral LLT was comparable with those after standard double lung transplantation (1- and 5-year survival in LLT was 82% and 64%, respectively).6 In addition, they reported that posttransplant functional outcomes were also equivalent between the groups (FEV1.0 at 1 year was 76% in LLT). The Australian group also demonstrated similar results to those from the Swedish group where they showed no significant difference in longterm survival between the LLT patients and non-LLT patients. Although both studies concluded that LLT did not increase the morbidity or mortality in lung transplantation,7 the small sample size (9 patients for 7 years in the Australian group and 23 patients for 12 years in the Swedish group) is an obvious limitation. With experienced hands, it is not technically demanding to perform lobectomy of any lobe in donor lungs on a back table, although lobectomy on donor lungs may be different from the pulmonary 95
LOBAR LUNG TRANSPLANTATION lobectomies that thoracic surgeons are accustomed to for lung cancer surgery because there may be no distended vascular structures. According to the published reports, the bronchial stump complication following a lobar transplant, which is the biggest technical concern, ranged from 0%-13%.4-7 Given all together, with our institutional experience with 3.1% (1/32) of bronchial stump complication rates, it should be emphasized that this lobectomy is not technically difficult but deserves special caution in the sense that all the postlobectomy structures, especially the bronchial stumps, are challenged in their healing by immunosuppression with high doses of steroids, interrupted bronchial blood supply, suboptimal oxygenation (from primary graft dysfunction), and suboptimal nutritional status following the surgery. Therefore, special technical considerations are important, including the optimal reinforcement techniques for covering the stumps. Additionally, these patients can have fairly complicated postoperative courses, and increased attention to fluid balance, steroid dosage, bronchoscopic surveillance is prudent. Regarding the recipients’ selection criteria for LLT, they have not been elaborately discussed in the recently published reports reviewed here. From
recipients' size standpoint, the mean height of the patients was 159 cm in the article from Sweden, whereas it was 156 cm in the article from Australia. The report from Sweden included 3 of 23 patients who were on prior extracorporeal membrane oxygenation, whereas the report from Australia seems to have included relatively stable patients with low LAS ranging from 28-41. Performing LLT can circumvent issues with donor-recipient size mismatch and it may help in particular instance when we encounter unexpectedly oversized donor lungs; however, it should be also recognized that this option should show the highest value when it is used as the last resort surgical option for the critically ill recipients whose transplant window is closing. Therefore, at this moment, we should be selective in recipients and donors for LLT. The recent experience with LLT described herein by these reports gives additional confidence that LLT is a viable option for patients who are size-mismatch challenged. Approaches and experience with this technique have the potential to afford decrease waiting-list mortality without significant difference in outcome. With a limited donor pool of organs, we believe options such as LLT is yet another important approach to significantly affect the field of lung transplantation.
1. Kozower BD, Meyers BF, Smith MA, et al: The right middle and lower lobes. Ann Thorac Surg 6. Keating DT, Marasco SF, Negri J, et al: Long-term impact of the lung allocation score on short-tem 57:219-221, 1994 outcomes of cadaveric lobar lung transplantatransplantation outcomes: a multicenter study. 4. Aigner C, Mazhar S, Jaksch P, et al: Lobar tion: Helping to maximize resources. J Heart J Thorac Cardiovasc Surg 135:166-171, 2008 transplantation, split lung transplantation and Lung Transplant 29:439-444, 2010 2. Horai T, Shigemura N, Gries C, et al: Lung peripheral segmental resection—Reliable proce- 7. Inci I, Schuurmans MM, Kestenholz P, et al: transplantation for patients with high lung dures for downsizing donor lungs. Eur J CarLong-term outcomes of bilateral lobar lung allocation score: Single-center experience. Ann diothorac Surg 25:179-183, 2004 transplantation. Eur J Cardiothorac Surg [Epub Thorac Surg 93:1592-1597, 2012 5. Marasco SF, Than S, Keating D, et al: Cadaveric ahead of print] 3. Bisson A, Bonnette P, et Kadi NB, et al: Bilateral lobar lung transplantation: Technical aspects. pulmonary lobe transplantation: Left lower and Ann Thorac Surg 93:1836-1842, 2012
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Seminars in Thoracic and Cardiovascular Surgery Volume 25, Number 2
Lobar Lung Transplantation: Emerging Evidence for a Viable Option Norihisa Shigemura, MD PhD, Jay Bhama, MD, Christian Bermudez, MD, and Jonathan D’Cunha, MD PhD The field of lung transplantation has seen an exciting evolution recently, with novel approaches to increasing the number of organs available for patients with end-stage lung disease. We review 2 recent reports describing the approach of lobar lung transplant as a successful and viable option for those recipients who are challenged by size mismatch and clinical course decline while on the transplant waiting list. Semin Thoracic Surg 25:95–96 I 2013 Elsevier Inc. All rights reserved. Keywords: lobar lung transplantation, size matching, donor, lobectomy, primary graft dysfunction, ECMO With the implementation of the lung allocation score (LAS) system, the demographics of the recipients have shifted, with an increased number of critically ill patients being considered for transplantation.1 Many transplant centers have numerous patients with small chests on their list who await the uncommon suitable donor. LAS does not take into consideration the size matching between donor and recipient lungs, which has a direct effect on waiting-list mortality for patients who are shorter than average Americans and those with restrictive lung disease. According to the most recent United Network for Organ Sharing data, the short group recipients (below 160 cm tall) waited for approximately 54 days more than average people (mean 168 cm tall) and the tall group patients (above 176 cm tall) waited approximately 59 days less than average people. If the short patients with restrictive lung diseases who need the smaller lungs wait for their ideal size-matching donors, their window for transplant would be very limited (or nonexistent). More importantly, recent data have demonstrated that lung transplantation in patients with high LAS is associated with significantly decreased survival and increased complications compared with patients with low LAS, the trend of which is more noticeable in patients with restrictive lung diseases.2 Therefore, the option of a lobar lung transplant (LLT) is potentially viable for those patients who have smaller than Department of Cardiothoracic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania. Address reprint requests to Norihisa Shigemura, MD, PhD, UPMC Presbyterian, Suite C-900, 200 Lothrop St, Pittsburgh, Pennsylvania 15213. E-mail: [email protected]
1043-0679/$-see front matter ª 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1053/j.semtcvs.2013.06.001
average chest cavities and restrictive lung disease because LLT can circumvent the issue of difficult organ availability, leading to potentially fewer cases of waiting-list mortality. This would hopefully translate into better transplant outcomes by transplanting at an earlier stage before a precipitous decline in the clinical course is encountered. Historically, the first report of LLT was described by a French group in 1994.3 Since then, this surgical option has been well addressed in a couple of reports by European and Australian groups4,5; however, interestingly, LLT has not yet been reported by the lung transplant centers in the United States. The report most recently published by a Swedish group demonstrated that the short- and long-term transplant outcomes after bilateral LLT was comparable with those after standard double lung transplantation (1- and 5-year survival in LLT was 82% and 64%, respectively).6 In addition, they reported that posttransplant functional outcomes were also equivalent between the groups (FEV1.0 at 1 year was 76% in LLT). The Australian group also demonstrated similar results to those from the Swedish group where they showed no significant difference in longterm survival between the LLT patients and non-LLT patients. Although both studies concluded that LLT did not increase the morbidity or mortality in lung transplantation,7 the small sample size (9 patients for 7 years in the Australian group and 23 patients for 12 years in the Swedish group) is an obvious limitation. With experienced hands, it is not technically demanding to perform lobectomy of any lobe in donor lungs on a back table, although lobectomy on donor lungs may be different from the pulmonary 95
LOBAR LUNG TRANSPLANTATION lobectomies that thoracic surgeons are accustomed to for lung cancer surgery because there may be no distended vascular structures. According to the published reports, the bronchial stump complication following a lobar transplant, which is the biggest technical concern, ranged from 0%-13%.4-7 Given all together, with our institutional experience with 3.1% (1/32) of bronchial stump complication rates, it should be emphasized that this lobectomy is not technically difficult but deserves special caution in the sense that all the postlobectomy structures, especially the bronchial stumps, are challenged in their healing by immunosuppression with high doses of steroids, interrupted bronchial blood supply, suboptimal oxygenation (from primary graft dysfunction), and suboptimal nutritional status following the surgery. Therefore, special technical considerations are important, including the optimal reinforcement techniques for covering the stumps. Additionally, these patients can have fairly complicated postoperative courses, and increased attention to fluid balance, steroid dosage, bronchoscopic surveillance is prudent. Regarding the recipients’ selection criteria for LLT, they have not been elaborately discussed in the recently published reports reviewed here. From
recipients' size standpoint, the mean height of the patients was 159 cm in the article from Sweden, whereas it was 156 cm in the article from Australia. The report from Sweden included 3 of 23 patients who were on prior extracorporeal membrane oxygenation, whereas the report from Australia seems to have included relatively stable patients with low LAS ranging from 28-41. Performing LLT can circumvent issues with donor-recipient size mismatch and it may help in particular instance when we encounter unexpectedly oversized donor lungs; however, it should be also recognized that this option should show the highest value when it is used as the last resort surgical option for the critically ill recipients whose transplant window is closing. Therefore, at this moment, we should be selective in recipients and donors for LLT. The recent experience with LLT described herein by these reports gives additional confidence that LLT is a viable option for patients who are size-mismatch challenged. Approaches and experience with this technique have the potential to afford decrease waiting-list mortality without significant difference in outcome. With a limited donor pool of organs, we believe options such as LLT is yet another important approach to significantly affect the field of lung transplantation.
1. Kozower BD, Meyers BF, Smith MA, et al: The right middle and lower lobes. Ann Thorac Surg 6. Keating DT, Marasco SF, Negri J, et al: Long-term impact of the lung allocation score on short-tem 57:219-221, 1994 outcomes of cadaveric lobar lung transplantatransplantation outcomes: a multicenter study. 4. Aigner C, Mazhar S, Jaksch P, et al: Lobar tion: Helping to maximize resources. J Heart J Thorac Cardiovasc Surg 135:166-171, 2008 transplantation, split lung transplantation and Lung Transplant 29:439-444, 2010 2. Horai T, Shigemura N, Gries C, et al: Lung peripheral segmental resection—Reliable proce- 7. Inci I, Schuurmans MM, Kestenholz P, et al: transplantation for patients with high lung dures for downsizing donor lungs. Eur J CarLong-term outcomes of bilateral lobar lung allocation score: Single-center experience. Ann diothorac Surg 25:179-183, 2004 transplantation. Eur J Cardiothorac Surg [Epub Thorac Surg 93:1592-1597, 2012 5. Marasco SF, Than S, Keating D, et al: Cadaveric ahead of print] 3. Bisson A, Bonnette P, et Kadi NB, et al: Bilateral lobar lung transplantation: Technical aspects. pulmonary lobe transplantation: Left lower and Ann Thorac Surg 93:1836-1842, 2012
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Seminars in Thoracic and Cardiovascular Surgery Volume 25, Number 2
