Objective: The International Society for Heart and Lung Transplantation has proposed a new grading system for primary graft dysfunction based on the ratio of arterial oxygen to fraction of inspired oxygen measured within 48 hours after lung transplantation. Worsening primary graft dysfunction grade is associated with increased operative mortality rates and decreased long-term survival. This study evaluated donor and recipient risk factors for postoperative International Society for Heart and Lung Transplantation grade 3 primary graft dysfunction.Methods: We reviewed donor and recipient medical records of 402 consecutive lung transplantations performed between 1992 and 2004. We calculated a worst International Society for Heart and Lung Transplantation primary graft dysfunction grade in the first 48 hours postoperatively. Severe primary graft dysfunction (International Society for Heart and Lung Transplantation grade 3) was defined by a ratio of arterial oxygen to fraction of inspired oxygen of less than 200. Associations of potential risk factors with grade 3 primary graft dysfunction in the first 48 hours postoperatively were examined through bivariate and multivariate analysis.Results: The 90-day mortality rate associated with the development of Intenational Society for Heart and Lung Transplantation grade 3 primary graft dysfunction in the first 48 hours postoperatively was 17% versus 9% in the group without grade 3 primary graft dysfunction. Significant bivariate risk factors associated with this end point were increasing donor age, donor smoking history of more than 10 pack-years, early transplantation era (1992-1998), increasing preoperative recipient pulmonary artery pressure, and recipient diagnosis. In the multivariate analysis only recipient pulmonary artery pressure, donor acre, and transplantation era were associated with grade 3 primary graft dysfunction in the first 48 hours postoperatively at a P value of less than .05.Conclusions: Our analysis of donor and recipient risk factors for severe primary graft dysfunction identified patient groups at high risk for poor outcomes after lung transplantation that might benefit from treatments aimed at reducing reperfusion injury.
Background: The use of a low-potassium-based preservation solution improves gas exchange in experimental models of lung transplantation. However, its efficacy in reducing the incidence of primary graft dysfunction (PGD) and improving patient outcomes in the clinical setting is controversial.Methods: In this study we measured: oxygenation index (01); International Society of Heart and Lung Transplantation (ISHLT) PGD grades; extubation times; intensive care unit (ICU) and hospital length of stay; 30-day, 90-day and 1-year survival rates; and bronchiolitis obliterans syndrome (BOS)-free survival. We compared 115 consecutive (2001 to 2004) lung recipients who received allografts preserved with Perfadex, a low-potassium dextran (LPD) solution, and compared the results with the previous 116 consecutive (1999 to 2001) lung recipients who received allografts preserved with modified Euro-Collins (MEC) solution. Recipients were classified as having severe PGD (ISHLT Grade III) if the lowest arterial oxygenation (P) to fraction of inspired oxygen (F) (P/F ratio) within 48 hours post-transplantation was < 200.Results: Baseline characteristics of the 2 cohorts were similar except for recipient age (LPD 53.5 vs MEC 49.9 years; p = 0.03). There were no differences in donor age, gender, category of transplant, indication for transplant, use of cardiopulmonary bypass or pre-operative pulmonary artery pressures. When gas-exchange parameters were measured upon arrival to the ICU (TO), at 24 hours post-transplant (T24) and at 48 hours post-transplant (T48), the only significant finding was that the incidence of ISHLT Grade III PGD at T24 was lower in the LPD group compared with the MEC group (8% vs 20%, P = 0.03). The incidence of severe PGD at other timepoints was not statistically different (LPD vs MEC: TO, 17% vs 26%; TO to T48, 25% vs 31%). Both groups had similar extubation rates at 48 hours post-transplant (LPD 64% vs MEC 67%). The 30-day survival (LPD 93% vs MEC 95%), 90-day survival (LPD 89% vs MEC 89%), 1-year patient survival (LPD 80% vs MEC 77%) and 1-year BOS-free survival (LPD 70% vs MEC 74%) were not statistically different.Conclusions: Lung preservation with LPD as compared with MEC does not improve early gas exchange or impact 90-day and 1-year mortality. Continued investigation into lung preservation solution composition is necessary to reduce the incidence of PGD.
Background: A scoring system was recently proposed to grade the severity of primary graft dysfunction (PGD), a frequent early complication of lung transplantation. The purposes of this study are to: (1) validate the PGD grading system with respect to patient outcomes; and (2) compare the performance of criteria employing the arterial oxygenation to fraction of inspired oxygen (P/F) ratio to an alternative grading system employing the oxygenation index (OI).Methods: We retrospectively reviewed the medical records of 402 patients having undergone lung transplantation at our institution from 1992 through 2004. The ISHLT PGD grading system was modified and grades were assigned up to 48 hours post-transplantation as follows: Grade 1 PGD, P/F > 300; Grade 2, P/F 200 to 300; and Grade 3, P/F < 200. A worst score T(0 - 48) was also assigned, which reflects the highest grade recorded between TO and T48.Results: The prevalence of severe PGD (P/F Grade 3) declined after transplant, from 25% at T0 to 15% at T48. Grouping patients by P/F grade at T48 demonstrated the clearest differentiation of 90-day death rates (Grade 1, 7%; Grade 2, 12%; Grade 3, 33%) (p = 0.0001). T48 OI grade also differentiates 90-day death rates. There was no difference in longer-term survival between patients with PGD Grades 1 and 2. OI grade at T0 qualitatively improved differential mortality between Grades 1 and 2; however, the differences did not reach statistical significance. Patients with a worst score T(0 - 48) of Grade 3 PGD did have significantly decreased long-term Survival, as well as longer ICU and hospital stay, when compared with Grades 1 and 2 PGD. Significant risk factors for short- and long-term mortality in our multivariate model were P/F Grade 3 [worst score T(0 - 48) as well as T0 grade], single-lung transplant, use of cardiopulmonary bypass and high pre-operative mean pulmonary artery pressure.Conclusions: There is an increased risk of short- and long-term mortality and length of hospital stay associated with severe (Grade 3) PGD. The proposed ISHLT grading system can rapidly identify patients with poor outcomes who may benefit from early, aggressive treatment. Refinement of the scoring system may further improve patient risk stratification.