Analysis of risk and prognostic factors of mortality in post-transplant patients in the intensive care unit

Objective

To assess mortality's predictive factors in a cohort of bone marrow transplanted (BMT) patients admitted to the ICU.

Design

A retrospective study.

Setting

A 12-bed medico-surgical ICU.

Patients

Twenty-nine patients on a total of 430 BMT (7%) from 1986 and 2004 were admitted to the ICU. Median age was 43 years and 22 patients were male (76%). Three main groups of underlying disease were found: three patients had acute myeloid leukaemia, 16 had acute myeloid leukaemia following myelodysplasia, 10 had lymphoproliferative diseases, 25 patients were neutropenic (86%), and 23 had less than 20,000 platelets/ml at admission to the ICU (79%). Nine had autologous transplant (2.7% of all autologous) and 20 allogenic transplants (20.4% of all allogenic). Numbers of supportive devices (such as mechanical ventilation or haemodialysis) were taken into account.

The SOFA score was calculated every day in the ICU (SOFA 0 at admission) and data were collected to calculate SOFA in the two days preceding ICU admission (SOFA -1 and SOFA -2). Main diagnoses at ICU admission were categorized as: acute respiratory failure without infection (ARF) and sepsis-related ARF (SD) that include severe sepsis and septic shock. Multivariate analysis with a logistic regression was used to analyze relationship between mortality and data regarding characteristics of patients, data regarding modality of transplant and cause of ICU admission. Univariate analysis was used to compare SOFA scores between groups.

Main results

ICU admission occurred 23 days after transplant (median value), causes of ICU admission were: ARF (10%), SD (83%), others (7%). Overall ICU mortality was 90%. Relationship with mortality was found for allogenic versus autologous (P = 0.04), neutropenic versus non-neutropenic (P = 0.03), cause of ICU admission (SD vs ARF, P = 0.026).

The highest SOFA value, mean SOFA value, SOFA -2, SOFA -1.0 and SOFA +1 were higher in patients who died in ICU. No association was found between SOFA variation (differences from SOFA -1 and SOFA +1 and, respectively, SOFA 0 and SOFA +1). No relationship was found between mortality and number of supportive devices, presence of severe thrombocytopenia, and underlying disease.

Conclusions

Our data support previously known risk factors for ICU mortality in BMT recipients. SOFA was confirmed to well describe organ failure and predict mortality. No cutoff value was found to be highly suggestive for bad prognosis. Non-neutropenic autologous BMT recipients admitted to the ICU for non-sepsis-related acute pathologic event has a relatively good prognosis.