The monitoring of electrical activity of the diaphragm (EAdi) is a new minimally invasive bedside technology that was developed for the neurally adjusted ventilatory assist (NAVA) mode of ventilation. In addition to its role in NAVA ventilation, this technology provides the clinician with previously unavailable and essential information on diaphragm activity. In this paper, we review the clinical interests of EAdi in the pediatric intensive care setting. Firstly, the monitoring of EAdi allows the clinician to tailor the ventilatory settings on an individual basis, avoiding frequent overassistance leading potentially to diaphragmatic atrophy. Increased inspiratory EAdi levels can also suggest insufficient support, while a strong tonic activity may reflect the patient efforts to increase its lung volume. EAdi monitoring also allows detection of patient-ventilator asynchrony. It can play a role in evaluation of extubation readiness. Finally, EAdi monitoring provides the clinician with better understanding of the ventilatory capacity of patients with acute neuromuscular disease. Further studies are warranted to evaluate the clinical impact of these potential benefits. 1. Introduction In the pediatric intensive care unit (PICU), up to half of patients require mechanical ventilation (MV) [1]. The objectives of this therapy are to support the failing respiratory muscles and allow better gas exchange while awaiting recovery. As simple a concept as MV may seem, it can be also detrimental and delay healing if not judiciously adjusted to the individual patient. Ventilation not synchronized with patients’ efforts, as well as both insufficient or excessive support, can delay recovery, prolong the MV duration, and contribute to muscle wasting [2, 3]. It has long been considered crucial to monitor the respiratory activity of critically ill patients in order to limit these complications, but available monitoring methods were complex and rarely used in clinical practice [4, 5]. Over the last decade, a new minimally invasive technology has been developed to continuously record the electrical activity of diaphragm (EAdi) at bedside. The main purpose of this technology is to synchronize and adapt the ventilatory support following the EAdi signal during the neurally adjusted ventilatory assist (NAVA) mode [6]. In addition to NAVA ventilation, EAdi monitoring also provides the clinician with a comprehensible continuous evaluation of the diaphragm’s function. The aim of this paper is to emphasize the importance of this new information in clinical practice. 2. Materials and
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