Patient–ventilator asynchrony during conventional mechanical ventilation in children

Abstract

BackgroundWe aimed (1) to describe the characteristics of patient–ventilator asynchrony in a population of critically ill children, (2) to describe the risk factors associated with patient–ventilator asynchrony, and (3) to evaluate the association between patient–ventilator asynchrony and ventilator-free days at day 28.MethodsIn this single-center prospective study, consecutive children admitted to the PICU and mechanically ventilated for at least 24 h were included. Patient–ventilator asynchrony was analyzed by comparing the ventilator pressure curve and the electrical activity of the diaphragm (Edi) signal with (1) a manual analysis and (2) using a standardized fully automated method.ResultsFifty-two patients (median age 6 months) were included in the analysis. Eighteen patients had a very low ventilatory drive (i.e., peak Edi < 2 µV on average), which prevented the calculation of patient–ventilator asynchrony. Children spent 27% (interquartile 22–39%) of the time in conflict with the ventilator. Cycling-off errors and trigger delays contributed to most of this asynchronous time. The automatic algorithm provided a NeuroSync index of 45%, confirming the high prevalence of asynchrony. No association between the severity of asynchrony and ventilator-free days at day 28 or any other clinical secondary outcomes was observed, but the proportion of children with good synchrony was very low.ConclusionPatient–ventilator interaction is poor in children supported by conventional ventilation, with a high frequency of depressed ventilatory drive and a large proportion of time spent in asynchrony. The clinical benefit of strategies to improve patient–ventilator interactions should be evaluated in pediatric critical care.

Pressure support ventilation, sigh adjunct to pressure support ventilation, and neurally adjusted ventilatory assist in infants after cardiac surgery: A physiologic crossover randomized study

“…Our data confirmed the high proportion of asynchronies registered during PSV in several pediatric studies . PSV SIGH did not show a significant reduction in AI if compared with PSV: as expected we reported an identical incidence of ineffective efforts, autotriggering and double triggering for these two modalities; interestingly we also registered a significant reduction in premature cycling during PSV SIGH.…”

Pressure Support Ventilation (PSV) versus Neurally Adjusted Ventilatory Assist (NAVA) in difficult to wean pediatric ARDS patients: a physiologic crossover study

“…Patient-ventilator synchrony is difficult to achieve with PSV in this specific population [31]. Generally, pediatric patients spend about one-third of the respiratory time with a suboptimal patient-ventilator interaction [32].…”

“…Several studies have reported that patients with PARDS are characterized by short ventilator free periods and longer length of mechanical ventilation in survivors [7]. Moreover, this specific population showed the worst patient-ventilator interaction [32][33][34].…”

Neurally adjusted ventilatory assist vs. pressure support to deliver protective mechanical ventilation in patients with acute respiratory distress syndrome: a randomized crossover trial

“…Triggering delay was the most common type of asynchrony in our study, and it was significantly reduced in NAVA compared to PSV. Since triggering delay greater than 0.15 s may cause considerable discomfort [26,43] and is easily measured with the NAVA catheter [44][45][46], we report its value but do not include it in the computation of AI to allow comparison of our results with other studies.…”