Which Mask for Noninvasive Ventilation in Acute Respiratory Failure?

Abstract

We read with great interest the recent report in CHEST (May 2011) by Ozsancak et al1Ozsancak O Sidhom SS Liesching TN Howard W Hill NS Evaluation of the total face mask for noninvasive ventilation to treat acute respiratory failure.Chest. 2011; 139: 1034-1041Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar comparing the total face mask (TFM) with the oronasal mask (ONM) for the treatment of acute respiratory failure by noninvasive mechanical ventilation (NIV). The authors found similar early NIV discontinuation rates in the TFM and ONM groups (16 of 29 vs 12 of 31, respectively). They also found that the median duration of NIV with the TFM was significantly shorter than with the ONM (6.05 h vs 15.7 h, excluding the total duration of NIV performed with the TFM and after the switch to the ONM). Figures 5 and 6 of their article showed similar improvement in dyspnea, respiratory rate, and oxygen saturation for both groups at 0.5, 1, and 3 h. However, the figures do not show the trend of Paco2, although its improvement was indicated as similar in the text, with P > .05. We would like to know what the mean improvement time of Paco2 and the mean duration of effective NIV (ie, not discontinued early [n = 12 of 29 TFM, 18 of 31 ONM]) were for each group in order to understand whether the TFM or the ONM permitted significantly quicker changes both in symptoms and in hemogas analysis. We also ask because none of the 12 patients using an ONM who discontinued use early from NIV was switched to a TFM. We believe that these points would permit us to better realize the advantages of one of the two masks in an acute setting. Which Mask for Noninvasive Ventilation in Acute Respiratory Failure?: ResponseCHESTVol. 140Issue 4PreviewWe appreciate the interest of Dr Barbarito and colleagues in our recent study1 comparing the total face mask (TFM) with oronasal mask (ONM) for the treatment of acute respiratory failure in patients receiving noninvasive ventilation (NIV). Our primary (mask comfort and time to apply) and secondary (vital signs and gas exchange parameters over time) end points showed no differences. In the interest of conserving space, we did not show the data for the time course of Paco2 in the two groups. Figure 1 shows that data after purging of early discontinuers (ie, those who discontinued NIV while still requiring ventilatory assistance) to provide a better idea of evolution over time. Full-Text PDF