Improved short- and long-term outcome of allogeneic stem cell recipients admitted to the intensive care unit: a retrospective longitudinal analysis of 942 patients

Intensive care unit (ICU) admission of allogeneic hematopoietic stem cell transplant (HSCT) recipients is associated with relatively poor outcome. Since longitudinal data on this topic remains scarce, we analyzed reasons for ICU admission as well as short- and long-term outcome of critically ill HSCT recipients. A total of 942 consecutive adult patients were transplanted at Hannover Medical School from 2000 to 2013. Of those, 330 patients were at least admitted once to the ICU and included in this retrospective study. To analyze time-dependent improvements, we separately compared patient characteristics as well as reasons and outcome of ICU admission for the periods 2000-2006 and 2007-2013. The main reasons for ICU admission were acute respiratory failure (ARF) in 35%, severe sepsis/septic shock in 23%, and cardiac problems in 18%. ICU admission was clearly associated with shortened survival (p < 0.001), but survival of ICU patients after hospital discharge reached 44% up to 5 years and was comparable to that of non-ICU HSCT patients. When ICU admission periods were compared, patients were older (48 vs. 52 years; p < 0.005) and the percentage of ARF as leading cause for ICU admission decreased from 43% in the first to 30% in the second period. Over time ICU and hospital survival improved from 44 to 60% (p < 0.01) and from 26 to 43% (p < 0.01), respectively. The 1- and 3-year survival rate after ICU admission increased significantly from 14 to 32% and from 11 to 23% (p < 0.01). Besides ARF and septic shock, cardiac events were especially a major reason for ICU admission. Both short- and long-term survival of critically ill HSCT patients has improved significantly in recent years, and survival of HSCT recipients discharged from hospital is not significantly affected by a former ICU stay.