Implications of the ISHLT 2005 and 2016 PGD Grading System

Purpose In 2005, an ISHLT working group proposed a grading system for primary graft dysfunction (PGD) following lung transplantation (LTx), based on oxygenation (P/F) and chest X-ray. This system was revised in 2016. The aim of this study is to compare the impact of the 2016 revised versus the original 2005 grading system on PGD prevalence and early post-LTx outcome. Methods All patients receiving double LTx at our institution between 12/2016 and 01/2018 (n=75) were retrospectively studied. P/F ratios were calculated and X-rays were scored by two experts blinded for clinical information at time (T) points 0, 24, 48, and 72 hours. PGD grading was determined separately according to 2005 and 2016 PGD definition. When multiple P/F ratios were available, the lowest P/F was used. Results Results are visualized in figure 1. PGD distribution at T0, T24, T72 differed between 2005 and 2016 (p Conclusion PGD grading differs between the original and the new PGD scoring system with a higher proportion of lower grades according to the 2016 definition at early time points. This might be explained by the more prominent role of chest radiography in the 2016 classification for PGD 0 regardless of the P/F ratio. On the other hand, according to the 2016 classification system, extubated patients are no longer automatically scored as PGD-0 or PGD-1, which might explain the higher proportion of PGD3 at T72. Early outcome was comparable between the two systems when patients suffered from PGD3 at any time point after transplantation. The impact of PGD grading on long-term outcome should be further investigated.