Given the complexity of the delirium concept and its context, a diagnostic algorithm was developed that may serve as a guide. The algorithm is the first part of a comprehensive flow chart comprising the various steps in the evaluation and management of the causes of emotional–behavioral disturbances at the PICU, which can vary from violent agitation in hyperactive delirium to the subtle complaint of the caregiver stating that “This is now no longer my child” in the hypoactive form. All available data sources may be used, including chart information.
The first step is the evaluation of the sedation-agitation level with the Richmond Agitation-Sedation Scale (RASS) [37
], the second the psychometric assessment of behavior with the PAED scale and the evaluation of the opinion of the caregivers, the third the identification and management of somatic and pharmacological causes, the fourth and fifth the assessment and management of discomfort as well as assessment of possible moderating qualities of the psychosocial environment. The last step represents the treatment of delirium with medication. The two scales (RASS and PAED) are completed by the nursing staff.
Diagnostic algorithm for pediatric delirium at the PICU.
*Procedure for RASS assessment.
- Observe patient. If patient is alert and calm, score 0. If patient is restless or agitated, score +1 to +4 (+1 = restless: anxious but movements not aggressive vigorous; +2 = agitated: frequent non-purposeful movement, fights ventilator; +3 = very agitated: pulls or removes tube(s) or catheter(s), is aggressive; +4 = combative: overtly combative, violent, immediate danger to staff).
- If not alert, state patient’s name and say to open eyes and look at speaker. If patient awakens with sustained eye opening and eye contact, score −1; if patient awakens with eye opening and eye contact, but not sustained, score −2; if patient has any movement in response to voice but no eye contact, score −3.
- When no response to verbal stimulation, physically stimulate patient by shaking shoulder and/or rubbing sternum. If patient has any movement to physical stimulation, score −4; if patient has no response to any stimulation, score −5.
**Procedure for PAED assessment.
- The child makes eye contact with the caregiver.
- The child’s actions are purposeful.
- The child is aware of his/her surroundings.
- The child is restless.
- The child is inconsolable.
Observe the patient and score the items.
Items 1, 2 and 3 are reversed scored as follows: 4 = not at all; 3 = just a little; 2 = quite a bit; 1 = very much; 0 = extremely. Items 4 and 5 are scored as follows: 0 = not at all; 1 = just a little; 2 = quite a bit; 3 = very much; 4 = extremely.
The scores of each item were summed to obtain a total Pediatric Anesthesia Emergence Delirium (PAED) scale score.
The algorithm is initiated by completing the RASS [37
]. Scoring takes 20 s. The RASS is a 10-point rating scale with four levels for agitation, five for sedation and one for calm, awake patients. Ratings are anchored according to a patient’s responses to verbal and then to physical stimulation. The RASS forms the starting point of the algorithm, as evaluating consciousness is always a first step in a neuropsychiatric examination. Second, it is important to start the evaluation of mental status with an objective rating that may identify both hyperactive and hypoactive presentations.
The next step is the PAED and the opinion of the caregivers about critical alterations in behavior and/or thinking of the child. Clinical anecdotal evidence indicates that their opinion is very important at least as an entry cue; it may even be considered diagnostic provided other causes have been excluded [see flow chart (Fig. )] in suspecting and diagnosing delirium [38
]. Some caregiver observations will coincide with items of the PAED discussed below. Other observations, however, are: loss of acquired skills, regression, catatonic features and paranoid thinking [15
Evaluation and management of emotional–behavioral disturbances at the PICU
The PAED is an easy tool, with no a priori exclusion criteria, which measures behavioral features that reflect disturbance of consciousness, inattention, emotional and cognitive changes and psychomotor disturbances [36
]. Since its introduction in 2004, six papers have been published regarding its value in children aged 1 to 6 years after an MRI procedure or anesthesiology for eye or dental surgery [41
Rating takes 1 min, and only minimal training is required. It is a 5-point scale with clear anchors. A score of 0–6 suggests that no further evaluation is required. A score of 7–9 indicates that the patient may be subsyndromal; it is therefore very important to re-evaluate clinical state after 1 h. A score ≥10 is compatible with delirium. Our first results with the PAED in a PICU context are promising: in a pilot multidisciplinary observational study at the PICU (n = 139), children with PD scored significantly higher on PAED than non-delirious children: mean PAED total score for delirious children was 12.8 (SD 3.7) and 3.2 (SD 3.5) for non-delirious children. The optimal PAED cutoff value had a sensitivity of 81%, a specificity of 91%, a diagnostic likelihood ratio of 9.3 and a post-test probability of 97% (article in preparation).
Because of the fluctuating course, we recommend assessment with the RASS, as an entry cue for this algorithm, every hour, whereas the PAED should be completed every nursing shift, in order to miss as few cases of delirium as possible.