Ventilator mode influence survival in noninvasive positive pressure ventilation?

Abstract

We read with interest the recent paper by Tsuboi et al.1Tsuboi Tomomasa Oga Toru Machida Kazuko Chihara Yuichi Matsumoto Hisako Niimi Akio Sumi Kensuke Ohi Motoharu Mishima Michiaki Chin Kazuo Importance of ventilator mode in long-term noninvasive positive pressure ventilation.Respir Med. 2009; 12: 1854-1861Abstract Full Text Full Text PDF Scopus (19) Google Scholar who reported that patients using noninvasive positive pressure ventilation (NPPV) in a pure controlled mode had significantly longer survival than those using an assisted mode in post-tuberculosis patients. Their data are very promising and the paper adds interesting information about the whole process of started NPPV, however we have some concerns about the conclusion of the authors. First of all, patients under NPPV (specially over 65 years old) had frequently extent preexisting medical comorbidities that influence mortality, and second, is unknown if NPPV was equal effectiveness in the two groups because any nocturnal test was reported to asses this point, apart from in the assisted ventilation group patients received less inspiratory pressure and less respiratory frequency that in the pure control group, that point could need some comments by the authors. We have doubts over the methods and the data showed in the paper of Tsuboi et al. could establish a firm relationship between ventilation modes and prolong survival; we need to include in the whole data more information about comorbidities (Charlson index) and nocturnal test to asses the quality of ventilatory support. The authors have no conflict of interest. Response to Drs Ramon Fernandez and Gemma RubinosRespiratory MedicineVol. 104Issue 2PreviewWe are grateful for the comments of Drs Ramon Fernandez and Gemma Rubinos regarding our article in Respiratory Medicine1 dealing with ventilator mode in long-term non-invasive positive pressure ventilation (NPPV). Full-Text PDF Open Archive