Frequency and predictors of NIMV(non-invasive ventilation) failure in patients with haematological malignancies presenting with acute respiratory failure(ARF) at a tertiary care hospital in Karachi, Pakistan

Abstract

Introduction: Patients with haematological malignancies(HM) are frequently at risk of developing acute respiratory failure(ARF) secondary to sepsis and its complications. Few studies have evaluated the outcome of non-invasive ventilation(NMIV) in these patients. Objective: To determine the frequency and predictors of NMIV failure in ARF in patients with haematological malignancies. Methods: Data on patients between ages of 18 to 75 years with HM who required NIMV due to ARF was collected from January,2012 to December 2014 at Aga Khan University hospital , Karachi , Pakistan. Patients with “not for intubation” status as advance directive were excluded. Results: Data on 54 patients was collected. The average age was 47.7±17.9 years. 66.7%(n=36)were male. 35.2%(n=19) failed NIMV and required invasive mechanical ventilation(IMV) out of which 47.4%(n=9) expired. The average length of hospital stay in patients successfully weaned on NIMV was 8.9±5.4 days while that of patients requiring IMV was 12.9±7.6 days. Independent factors associated with NIMV failure were requirement of vasopressors(OR 15.16, 95%CI 3.22-71.38, p= 0.0006), acute renal failure (OR 17.25, 95% CI 0.57-63.49,p=0.0003)) and presence of bilateral pulmonary infilterates(OR 7.79, 95%CI 1.91 to 31.01, p=0.004).Other factors that were studied but were not found to be statistically significant were presence of neutropenia(p=0.911) and hypercapnia at presentation(p=0.89). Conclusion: The frequency of NIMV failure in patients with HM presenting with ARF is high . Those who fail NIMV are at a high mortality risk.