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Abstract

We thank Drs Takir and Esquinas for their insightful commentary regarding our findings.1Stefan M.S. Nathanson B.H. Priya A. et al.Hospitals' patterns of use of noninvasive ventilation in patients with asthma exacerbation.Chest. 2016; 149: 729-736Abstract Full Text Full Text PDF PubMed Scopus (14) Google Scholar In our study, we analyzed data from the electronic medical records of 58 hospitals. We adjusted for patient case mix and several variables indicative of disease severity, including the Laboratory Acute Physiological Score, which integrates 14 laboratory tests, including arterial blood gas,2Escobar G.J. Greene J.D. Scheirer P. Gardner M.N. Draper D. Kipnis P. Risk-adjusting hospital inpatient mortality using automated inpatient, outpatient, and laboratory databases.Med Care. 2008; 46: 232-239Crossref PubMed Scopus (227) Google Scholar and for prior noninvasive ventilation (NIV) or invasive ventilation (intermittent mandatory ventilation [IMV]). The models predicting NIV and IMV use had strong discriminatory ability with c-statistics > 0.78 using only patient-level variables as fixed effects. Patient characteristics did not differ according to hospital quartiles of adjusted NIV rates. Moreover, we performed a hospital-level rather than patient-level analysis, which greatly reduces the risk of confounding by indication. Nevertheless, we agree that a study limitation is its lack of information about prior pulmonary function test results. Examining where NIV is delivered and the outcomes related to those decisions merits further investigation. Our data set did not have the granularity needed to assess the place of NIV delivery or where the patient was located when NIV failed and endotracheal intubation occurred. One prospective study that examined the place of delivery for NIV found that the success rate was higher if NIV was delivered on the general ward than in the ICU, which reflected the more acute nature of patients in the ICU.3Ozsancak Ugurlu A. Sidhom S.S. Khodabandeh A. et al.Use and outcomes of noninvasive positive pressure ventilation in acute care hospitals in Massachusetts.Chest. 2014; 145: 964-971Abstract Full Text Full Text PDF PubMed Scopus (56) Google Scholar We entirely agree with Drs Takir and Esquinas that the wide variation in the rate of NIV use among hospitals is largely related to the lack of randomized controlled trials on the effectiveness of NIV in asthma exacerbation. In a recent patient-level analysis, we found that patients with asthma exacerbation successfully treated with NIV appear to have better outcomes than those treated with IMV, but those in whom NIV failed had an increased risk of mortality, highlighting the need for careful monitoring to avoid a possible delay in intubation.4Stefan M.S. Nathanson B.H. Lagu T. et al.Outcomes of noninvasive and invasive ventilation in patients hospitalized with asthma exacerbation.Ann Am Thorac Soc. 2016; http://dx.doi.org/10.1513/AnnalsATS.201510-701OCPubMed Google Scholar Further studies are indeed needed to determine which patients with asthma exacerbations would benefit from NIV. Our study showed that hospital variation in NIV remained after adjusting for hospital characteristics and patient case mix. The results suggest that at hospitals with high NIV rates, physicians were not using NIV as an alternative to IMV but were instead lowering the threshold for initiating NIV. More research is needed to characterize the contextual factors used in the ventilation management of these patients in hospitals with high rates of NIV use and low rates of IMV use. Hospitals’ Patterns of Use of Noninvasive Ventilation in Patients With Asthma ExacerbationCHESTVol. 149Issue 3PreviewLimited data are available on the use of noninvasive ventilation in patients with asthma exacerbations. The objective of this study was to characterize hospital patterns of noninvasive ventilation use in patients with asthma and to evaluate the association with the use of invasive mechanical ventilation and case fatality rate. Full-Text PDF Hospitals’ Patterns of Noninvasive Ventilation in Asthma: Evidence or Deep Recommendations Needed?CHESTVol. 150Issue 2PreviewRespiratory failure is a frequent cause of death that is increased in the absence of ventilatory support. Noninvasive ventilation (NIV) is succesfully used to improve gas exchange, avoid endotracheal intubation, and reduce mortality in respiratory failure.1,2 There is good evidence to support NIV use as the first-line treatment in respiratory failure due to COPD exacerbations, but the evidence for use in acute asthma attacks is less compelling.3 Full-Text PDF