The aim of this study was to consider feasibility and safety of early mobilization for children from 0 to 2 years at PICU. Practice recommendations for early mobilization in critically ill children are poorly described [15, 16].
The feasibility and safety of early mobilization were evaluated within 20 sessions with patients from 1 day to 14 months admitted at PICU. Heart rate, systolic blood pressure and diastolic blood pressure showed no change immediately after the mobilization (T1), compared with baseline. Respiratory rate and SpO2 were similar at the different times. No technical adverse events were recorded. Our results are similar to other paediatric studies. Choong and al. demonstrated no difference in cardio-respiratory and hemodynamic parameters after passive mobilization with cycloergometer or active mobilization with video game for children aged from 3 to 17 years . Abdulsatar and al. also reported feasibility of a 25 minutes WII session for 8 children aged from 3 to 18 years without change in heart rate, respiratory rate, blood pressure and pulse oximetry, compared with baseline . Moreover, these studies showed no accidental tube dislodgements, extubations and cutaneous or physical injuries.
Sixteen sessions were feasible and mobilization sessions were discontinued in 4 cases (20%). Children were calm and stable before treatment but they twisted and turned during the mobilization. That agitation had impact on the EDIN and COMFORT-B scores in these children. The return to calm was possible without additional sedation. To our knowledge, our study is the first to describe agitation as an adverse event. The European PARK-PICU study reported 6% potential adverse events: the most commonly reported occurrences were decreased oxygen saturation, change in heart rate and in blood pressure . Adverse events are also described in critically ill adults. Schweickert and al. met one severe adverse event in 498 mobilization sessions in ventilated patients (desaturation less than 80%) . Hickmann et al. reported that adverse events occurred in 10 activities (0.8% of total sessions) such as hypotension, hypertension and tachycardia . The incidence of adverse events of early mobilization in critically ill adults ranges from 1–6% including change in parameters, tube removals, skin injuries and falls [20–23].
Agitation can be defined as a behavioural symptom with multiple origins like hypoxia, hunger, excessive stimulations, neurological instability, tiredness or pain [24, 25]. Literature has revealed several causes: post-surgical agitation, delirium, benzodiazepine or opioid withdrawal symptoms and personal characteristics.
Studies showed that agitation was common for children after surgery. Some risks factors are known: young age, short time to awakening, use of anaesthesia drugs . Most of patients in our study (17/20) were at PICU after a surgical procedure. All of them were affected by young age and contact with those drugs. However, time to awakening was longer because patients were transferred to PICU under sedation that was progressively decreased. Fear, pain and discomfort would also have impact on agitation. Pathology itself or invasive care could likewise cause agitation . In addition, important anxiety from parents or child himself may lead to a predisposition to agitation .
Sedation and analgesia were used to ensure safety and control agitation during mechanical ventilation. Continuous use of benzodiazepine is known to be associated to delirium risk factor . Delirium can be hypoactive with apathic behaviour or hyperactive with agitation and irritability or both. The delirium rate decreased to 11.9 % after the implementation of protocols about sedation and early mobilization . It is still now difficult to detect and probably underdiagnosed. When a child hospitalized in PICU shows signs of agitation or confusion, it is not possible to determine whether this is due to delirium rather than the underlying disease or environment related anxiety. Delirium could explain some agitation episodes in our study although continuous infusions of midazolam are not used in our PICU.
Benzodiazepine or opioid withdrawal symptoms can also cause irritability, delirium, agitation and anxiety. However, it is less likely to be applicable in this study because of the time to apply mobilization was between 24 and 48 hours of admission while withdrawal symptoms are related to the cumulated dose of sedative/analgesics drugs .
Finally, children’s own characteristics should not be excluded as an explanation. It is known that children more impulsive, less sociable and less flexible to environment changes are likely to be agitated after surgery [26, 28].
We used facilitators like pacifier, glycerin, cuddy toy, music or massage to relax the child during the mobilization. These facilitators could be considered as bias for evaluation of child behavior face with early mobilization. However, nursing staff regularly uses those techniques during the treatments and this is a non-pharmacologic option to avoid increasing sedation and antalgics. So, we considered this way as common during the physical therapy session with infants.
Balance between under-sedation and over-sedation is challenging. Children must be sedated to ensure their safety and comfort while keeping a level of alert during the day. Validated scales must be used to optimize analgesia and minimize sedation and, thus, prevent the delirium risk [29, 32].
Several limitations in our study should be noted. Firstly, we did not record the doses of drugs for each child. Nevertheless, this study was performed in an unit with a strong culture to optimize analgesia and minimize sedation while maintaining the safety and comfort of the infant. Use of sedative and analgesic medications were based on international recommendations . The specific choice of drug and its administration interval depended on the personal feeling of the physician in charge of the child. Finally, our study did not evaluate the benefits of early mobilization. Muscular strength in young children is difficult to evaluate in clinical settings due to lack of non-invasive and reliable assessment tools. Peripheral muscle ultrasound could be a promising tool for the muscle evaluation at bedside of children [33–36].