LUNG DISEASES: A CLOSER LOOK 

Minerva Pneumologica 2012 December;51(4):153-6

Copyright © 2012 EDIZIONI MINERVA MEDICA

language: English

A prospective study of patients with hypercapneic/acidotic respiratory failure who did not respond to non invasive ventilation and did not proceed to invasive ventilation

Sinha R. K. ¹, Ahmed N. ²

¹ Respiratory Department, Yeovil District Hospital, Yeovil, UK; ² Respiratory Department, Yeovil District Hospital, Yeovil, UK

AIM: The aim of this paper was to study the subgroup of patients with hypercapnoeic/acidotic respiratory failure who do not show signs of improvement at the first assessment after initial treatment with non-invasive ventilation (NIV) and do not proceed on to have treatment with invasive ventilation, in order to identify the factors associated with their management that may potentially influence their outcome.
METHODS: Patients showing persistent acidosis and hypercapnea with or without hypoxia and/or remaining clinically unwell at the first assessment after initial treatment with NIV, were recruited to the study between October 2008 and February 2009. Data were analyzed to see if prognostic factors found to be present at the outset and said to carry a poor prognosis were also associated with poor outcome if identified at a later stage at the first assessment after initial treatment with NIV.
RESULTS: Thirty-three percent of patients died whilst still in hospital and 45% died after 60 days. Persistence of acidosis, hypercapnoea and hypoxia were associated with poor outcome in this subgroup of patients as well, which is similar to what has been reported in the literature to be the case in patients who exhibit these features at the time of initial presentation. The outcome was also poor if patients remained tired, exhausted and unwell at the time of first assessment after initial treatment with NIV, did not tolerate NIV well or had associated comorbidities. The outcome was more favorable if the main primary diagnosis was pneumonia than if it was chronic obstructive pulmonary disease (COPD), in contrast to reports from previous studies. It was not clear if some of the factors such as a patient not being under the care of a respiratory physician and medical personnel below the grade of a consultant making decision about not to escalate treatment to invasive ventilation had any adverse effect on the final outcome of patients. We also realized that parameters required to calculate some of the complex prognostic formulas such as APACHE II and SAPS II scores suggested by previous investigators are not always recorded or readily available in the real life situation.
CONCLUSION: Some of the parameters in patients with acidotic/hypercapneic respiratory failure that influence their outcome if present at the time of presentation are also applicable in predicting the outcome if found to be present at the time of first assessment after initial treatment with NIV, although we have found some exceptions. Additionally, some organizational factors may also have potential to influence the outcome adversely and if proven to be so, steps could be taken to change and remedy them. This could be done with reasonable ease and would improve patient’s outcome. Further larger studies are required to address this point.