Author's reply

Abstract

We thank Esquinas et al. for their interest in our study [[1]Kinoshita M. Okayama H. Kawamura G. Shigematsu T. Takahashi T. Kawata Y. Hiasa G. Yamada T. Kazatani Y. Beneficial effects of rapid introduction of adaptive servo-ventilation in the emergency room in patients with acute cardiogenic pulmonary edema.J Cardiol. 2017; 69: 308-313Abstract Full Text Full Text PDF PubMed Scopus (10) Google Scholar]. Acute cardiogenic pulmonary edema (ACPE) often requires mechanical ventilation and the in-hospital mortality rate is high. Noninvasive positive pressure ventilation (NPPV) significantly decreases mortality and reduces the rate of endotracheal intubation (ETI) in patients with ACPE [[2]Antonelli M. Pennisi M.A. Montini L. Noninvasive ventilation in the clinical setting-experience from the past 10 years.Crit Care. 2005; 9: 98-103Crossref PubMed Scopus (36) Google Scholar]. Adaptive servo-ventilation (ASV) can be used seamlessly from the hospital's door to the general ward, and occasionally at home. In addition, favorable acute effects of ASV are reported in heart failure (HF) patients [[3]Asakawa N. Sakakibara M. Noguchi K. Kamiya K. Yamada S. Yoshitani T. Ono K. Oba K. Tsutsui H. Adaptive servo-ventilation has more favorable acute effects on hemodynamics than continuous positive airway pressure in patients with heart failure.Int Heart J. 2015; 56: 527-532Crossref PubMed Scopus (8) Google Scholar]. ASV has better compliance than continuous positive airway pressure (CPAP) or bi-level-positive airway pressure (BiPAP) [[4]Philippe C. Stoïca-Herman M. Drouot X. Raffestin B. Escourrou P. Hittinger L. Michel P.L. Rouault S. d’Ortho M.P. Compliance with and effectiveness of adaptive servo ventilation versus continuous positive airway pressure in the treatment of Cheyne-Stokes respiration in heart failure over a six month period.Heart. 2006; 92: 337-342Crossref PubMed Scopus (290) Google Scholar]. In our study, we evaluated the effect of ASV use in the emergency room in patients with ACPE. In patients with ACPE, rapid introduction of ASV in the emergency room reduced the need for ETI and decreased the hospital period. We agree with comments of Esquinas et al. that our study has several limitations. Our study was a retrospective study and potential bias depending on the physician was not absolutely excluded. However, hemodynamics, laboratory data, echocardiographic data, oxygen flow rate in the emergency room, and medications during hospitalization were not different among the groups. ACPE was defined according to the guideline of the Japanese Circulation Society (JCS) (dyspnea, orthopnea occurred and we heard a moist rale. Pulmonary edema was shown by radiograph). All patients in our study were really diagnosed as having ACPE. In the guideline of the JCS, NPPV is the first line of treatment for ACPE. Of course, we introduced ASV or conventional NPPV before ETI in almost all cases except in cardiogenic shock and disturbance of consciousness. It is important to understand etiology and pathological mechanisms for management of HF because etiology of HF and cardiac rhythm affect cardiac response to CPAP on acute phase [[5]Schlosshan D. Elliott M. Prognostic indicators in patients presenting with acute cardiogenic pulmonary edema treated with CPAP: it's not the acid that matters, it's back to basics.Crit Care. 2010; 14: 1009Crossref PubMed Scopus (8) Google Scholar]. In particular, it is reported that atrial fibrillation (AF) decreases cardiac index. In our study, the prevalence of AF was significantly higher in the ASV group. This is a limitation of a retrospective study that was not randomized. Although the condition in ASV group might be worse than that in the control group, ASV was effective in patients with such a background. However, as Esquinas et al. suggested, it would be important to know if data were prospectively collected or data mining was also retrospectively performed at the time of analysis, such as propensity score match would be needed for better match of background. We also hope that a large, prospective study comparison between CPAP and ASV will be started. Finally, we hope that our reply will address the problems that Esquinas et al. suggested. Once again, we would like to appreciate his interest in our study.