Over sedation among critically ill adult patients in intensive care units has been shown to be associated with longer duration of ventilation, longer hospital stay and adverse patient outcomes, such as withdrawal and delirium. Daily sedation holds have been shown to mitigate many of these problems. However, the evidence in the critically ill pediatric population is not well established. Vet et al. have conducted a multicentre randomized control trial among intensive care units in the Netherlands comparing protocolized sedation (PS) to protocolized sedation with daily sedation interruptions (PS+ DSI).
There was no difference between groups in ventilator-free days. The cumulative drug doses did not significantly differ between the two groups. The need for intermittent bolus administration in the DSI + PS group counterbalanced the reduction in continuous sedation. The essence of DSI is to minimize sedation use. The authors argue that protocolized management in control arm may have minimized sedation such that it negated any potential beneficial effect in the treatment arm. However, not all studies demonstrate a benefit in protocolized sedation practice. Furthermore, the expected mean number of ventilator-free days in the sample size calculation was lower than observed in the study, likely due to the selection of relatively more stable patients.
The authors also discuss the increased mortality among the treatment group. This is most likely to represent a type 1 error. No explanation for the increased deaths was found by independent review, and similar studies do not demonstrate a similar finding. Furthermore, the authors claim that the ‘timeframe between active participation in the study and death makes a causal relationship unlikely’.
In the PS group, there were significantly more re-intubations compared to the PS +DSI group (9 vs. 2, p = 0.03). The authors suggest that patients in the DSI + PS group were possibly more alert and therefore extubation may have been more successful. However, relatively small numbers make it difficult to be certain.
There are two previous studies of DSI in pediatric populations. Both show shorter durations of mechanical ventilation, shorter ICU stays and less use of sedatives. However, protocolized sedation was not used in the control arm of one study and the primary pathology among patients in the other study was very different (with a predominance of neurological as opposed to respiratory illness).
It is difficult to draw any firm conclusions from this study based on the small number of patients enrolled. However, it raises a number of important issues, including the difficulty in recruiting patients in pediatric ICU studies. A pragmatic protocol, which may allow a greater proportion of screened patients to be enrolled, may benefit future studies.
European Society of Intensive Care Medicine http://tinyurl.com/hsajzzt