Changes in outcomes (1996-2004) for pediatric oncology and hematopoietic stem cell transplant patients requiring invasive mechanical ventilation

Abstract

Objective: To assess the following hypotheses regarding mechanically ventilated pediatric oncology patients, including those receiving hematopoietic stem cell transplant (HSCT) and those not receiving HSCT: 1) outcomes are more favorable for nontransplant oncology patients than for those requiring HSCT; 2) outcomes have improved for both populations over time; and 3) there are factors available during the time of mechanical ventilation that identify patients with a higher likelihood of dying.

Design: Retrospective review.

Setting: Free-standing, tertiary care, pediatric hematology oncology hospital.

Patients: All patients requiring invasive mechanical ventilation with a diagnosis of cancer or following HSCT from January 1996 to December 2004.

Interventions: Bivariate and multivariate analysis. Dates of admission were grouped into time periods for analysis: 1996-1998, 1999-2001, and 2002-2004.

Measurements and main results: There were 401 courses of mechanical ventilation (329 patients) analyzed. Forty-five percent of HSCT admissions (92 of 206) vs. 75% of non-HSCT oncology admissions (146 of 195) were extubated and discharged from the pediatric intensive care unit (p < .0001). Twenty-five percent of HSCT vs. 60% of non-HSCT admissions survived 6 months (p < .0001). Among admissions with an abnormal chest radiograph and a PaO2/FiO2 ratio <200, pediatric intensive care unit survival increased for each successive time period, with 45% of HSCT and 83% of non-HSCT admissions surviving during 2002-2004. In multivariate analysis of all study patients, Pediatric Risk of Mortality scores on the day of intubation, allogeneic HSCT, cardiovascular failure, hepatic failure, neurologic failure, a previous course of mechanical ventilation within 6 months, and the time period intubated were associated with mortality. With the exception of time period, these same variables were associated with mortality in multivariate analysis of only HSCT patients.

Conclusions: HSCT patients who require mechanical ventilation have worse outcomes than non-HSCT oncology patients. Outcomes for both groups have improved over time. Allogeneic transplant, higher Pediatric Risk of Mortality scores, need for repeated mechanical ventilation, and concomitant organ system dysfunction are risk factors for death.