Spectrum of issues and outcomes of critically Ill pediatric hemopoietic stem cell transplant recipients requiring admission to intensive care unit in a tertiary care hospital in India

Abstract

Background : Hematopoietic stem cell transplantation (HSCT) is a lifesaving therapeutic option for children with multiple hematologic, oncologic, and immunologic disorders. However, a large proportion of children undergoing HSCT develop complications that necessitate admission to the pediatric intensive care unit (PICU). Methods : Study design: Retrospective chart review Setting and patient description: All children younger than 18 years of age, who received an HSCT in our hospital between August 2013 and June 2015, were identified from the HSCT database. Patients admitted to the ICU after HSCT were identified from a prospectively maintained ICU database. Patient data collected from medical charts included demographic information, pre-existing diagnosis requiring HSCT, number and type of transplantation, type of donor and source of stem cells, any complications if associated. Consent: Prior to the start of the HSCT procedure, all parents, and when appropriate, all patients, gave written informed consent to analyse clinical data for study purposes. PICU data: Indication for PICU admission, diagnosis, ventilator and inotrope requirement, if applicable and organ dysfunction. The outcome of patients, whether survival or death at discharge and follow up at 28days were done. Statistics: Descriptive and inferential statistical analysis has been carried out in the present study using SPSS 15.0. Results : During the study period, 141 children received HSCT of which 28 children required PICU admission on 33 occasions accounting for a PICU admission rate of 23.4%. Majority of patients were in the age group of 1-5yrs - 20 (60.6%), followed by 6-10yrs- 5(15.2%). The majority had a non-malignancy indication for HCST -22 (66.6%), of which thalassemia was the commonest diagnosis, followed by severe combined immunodeficiency (SCID) and adreno-leucodystrophy. The most common indications for PICU admission were seizures (n=10, 30.3%), hypotension (n=7, 21%) and respiratory distress (n=6, 18%). Sepsis or severe sepsis occurred in 75%, with pneumonia being the commonest focus in 44%. We observed a 64% (n=21) survival following PICU admission. While 26 (80%) patients with severe sepsis were culture positive, gram-negative bacilli were the commonest organisms. The most common organ dysfunction observed was respiratory failure (n=20, 60%) followed by neurological dysfunction (n=15, 45.5%). Acute kidney injury was observed in 11 (33%) patients, of which 5 (45%) required renal replacement therapy. Circulatory failure with hypotension had the highest risk of mortality. Other risk factors significantly associated with mortality were kidney injury(p-0.005), duration of mechanical ventilation (>5days)(p-0.009) and higher inotropic score (>10)(p- 0.004)). Septic shock was the most common cause of mortality in 6 (50%), followed by GVHD in 3 (25%) children. PICU survival was unaffected by the age characteristics, underlying condition or the type of HSCT. Conclusion : Immunocompromised children who need PICU admission after HSCT have high risk of death, especially in the presence of multi-organ failure, of which circulatory dysfunction appeared to have the greatest risk. In our study we observed 64% survival, which is better than previous studies in similar cohorts and comparable to western data. However, survival can be optimized by aggressive multidisciplinary ICU support.