In Reply:

We are grateful for the thoughtful comments from the authors about the findings of our report.¹ Certainly, the well-balanced comments express the experience of this group related to the postoperative care of patients who underwent coronary artery bypass graft surgery.

Very few studies have addressed the correlation between tissue perfusion markers and the use of noninvasive ventilation (NIV). Despite the concerns surrounding the timing of NIV application and the short duration, data from our forthcoming studies have strengthen the findings now reported.² Regarding the intra-operative course, none of our subjects had mechanical circulatory support with an intra-aortic balloon pump, which is not part of our routine operative strategy. The stratification by technique, either on-pump or off-pump, has already been clarified in our report, where allocation to the technique was based on the surgeon's expertise and not on the severity and extension of the coronary disease.³

Ongoing work from our group will provide new information about the impact of the surgical procedure on the emergent and increasingly high-risk population of patients referred for coronary artery bypass surgery, especially those with COPD⁴ and left ventricular dysfunction, where current information is worryingly scarce. It is therefore important to emphasize the potential role of NIV as an additional strategy for improving the postoperative care of these high-risk patients, allowing early and safe mobilization after coronary artery bypass graft surgery.

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