Transfer in ICU of febrile neutropenic patients: identification of risk factors and prospective validation of a prognostic score

Objective

Optimal strategy of referral for neutropenic patients from hematology ward to intensive care unit is not yet well defined. Different severity-of-illness scores used in ICU have been recently tested in hematology wards and have failed to predict accurately patients at 'high risk', who could require a pre-emptive transfer in ICU. We performed a case–control study in post-chemotherapy neutropenic patients (for leukaemia or lymphoma), aimed at identifying early risk factors for ICU transfer.

Design

Monocentric, retrospective, case–control (equilibration on age, sex, and type of hemopathy) study comparing febrile neutropenic patients admitted or not in ICU.

Results and measurements

Eighty-two patients have been included (41 cases, 41 controls). Patients included were 51% men, were aged 43 ± 17 years. The majority were hospitalized for an acute myeloblastic leukaemia (56%), the others for acute lymphoblastic leukaemia (30%) or lymphoma (13%). Most of the patients had clinical manifestations of infection (62%) but only 31% a microbiologically demonstration of infection. 61.7% of the patients were not in remission at time of admission in ICU. Mortality in ICU was 65.8%. We compared data between neutropenic patients (referred or not referred in ICU) during their stay in hematology ward. We distinguished an early period (within 72 hours after the onset of febrile neutropenia) and a later period (72 hours before transfer in ICU or before discharge from hospital). Comparing data between these patients during the early period highlighted that urea, creatinin, protein C-reactive, and fibrinogen levels significantly increased whereas hematocrit, platelets and lymphocytes levels were significantly decreased, in patients referred in ICU. Using these 'early' independent risk factors, we define a prognostic score identifying patients who could benefit of an early transfer in ICU. A multicenter, prospective study is now being performed on a second cohort to validate accuracy, adequacy and reliability of this score.

Conclusion

Nowadays, no prognostic score focused on identification of 'high-risk' neutropenic patients has been yet validated. This study allowed the identification of early risk factors independently associated with transfer in ICU. The clinical use in haematology wards of such a prognostic score should allow earlier pre-emptive transfers in ICU, resulting in better management and possibly a better outcome for these patients.