Alpha-2 adrenergic agonists | Dexmedetomidine | In general: a study aiming to facilitate weaning of delirious postoperative patients from mechanical ventilation concluded that dexmedetomidine may help to eliminate the emergence of agitation and can be a good treatment choice for delirium after cardiac surgery.34 Beneficial effects:
reduced incidence and duration of delirium5
reduced rescue sedation with intravenous midazolam and propofol35
reduced of opioid demand35
positive effect on sleep architecture: a meta-analysis of randomised controlled studies suggested that dexmedetomidine could help to reduce delirium in critically ill patients.36
Compared with traditional sedative agents (eg, propofol):
No effect:
No conclusive effect:
|
Clonidine |
No evidence for reduction of ventilator days.16
No evidence for reduction of ICU length of stay.16
Moderate quality evidence for reduced delirium risk (also valid for dexmedetomidine).16
|
Antiepileptic drugs | Gabapentin |
|
Antipsychotics: atypical | All |
|
Risperidone |
Moderate quality evidence for reduced delirium risk (also valid for dexmedetomidine) after emergency or elective cardiac surgery.40
Contradiction of benefit for prevention/treatment of delirium.41 42
Superior to haloperidol in postcardiotomy delirium.39
Two studies concentrated on risperidone: in the first study, a lower incidence of delirium was determined by the administration of a single dose of risperidone soon after cardiac surgery with cardiopulmonary bypass.42
The second study report edits administration for subsyndromal delirium after on-pump cardiac surgery to be associated with a significantly lower incidence of delirium.41
Failure to treat subsyndromal delirium with risperidone as an independent risk factor for delirium.41
|
Antipsychotics: typical | Haloperidol |
Dexmedetomidine superior to haloperidol in postcardiotomy delirium. Evidence for treatment of delirium.43
Concerns about safety and efficacy in delirium treatment.44
|
Benzodiazepines | All |
Dexmedetomidine might be superior alternative for light sedation.38
High risk for developing agitation, especially during weaning towards extubation.45
|
Midazolam |
Effect on postoperative cognition equivalent to propofol.46
Incidence of postcardiotomy delirium 50% compared with 3% in dexmedetomidine group.5
Dexmedetomidine superior to midazolam for sedation of mechanically ventilated patients concerning prevalence of ICU delirium.5 47
|
Cholinesterase inhibitors | Rivastigmine |
|
Hormones | Melatonin |
|
Hypnotics | Ketamine |
Only evidence for prevention of delirium with a single dose of ketamine 0.5 mg/kg intravenously during anaesthetic induction.51
Moderate quality evidence for reduced delirium risk (also valid for dexmedetomidine).44
Ketamine attenuates postoperative delirium after cardiac surgery using cardiopulmonary bypass and has an anti-inflammatory effect.51
Ketamine may exert neuroprotective effects after global and focal cerebral ischaemia, trauma, hypocapnia-induced chronic cerebral hypoperfusion and models of vasogenic brain oedema.51
Ketamine may either occur by prevention of excitotoxic injury apoptosis after cerebral ischaemia or by preservation of cerebral perfusion pressure by sympathetic nervous system stimulation and suppression of inflammatory CNS responses to CNS injury.51
Preliminary data from the authors’ research group suggested that ketamine protects against postoperative cognitive dysfunction in older patients who underwent cardiac surgery.51
|
Propofol |
Dexmedetomidine is superior to propofol for sedation of mechanically ventilated patients concerning prevalence of ICU delirium: incidence of postcardiotomy delirium is 50% compared with 3% in dexmedetomidine group.5
Moderate quality evidence for reduced delirium risk (also valid for dexmedetomidine).44
Dexmedetomidine might be a superior alternative for light sedation.38
|
Opioids | All |
Dexmedetomidine might be a superior alternative for light sedation.38
High risk for development of agitation, especially during weaning towards extubation.45
|
Morphine |
Similar incidence of delirium, but patients sedated with dexmedetomidine suffered 3 days less from delirium.52
Incidence of delirium significantly lower in a little subgroup with IABP treated with dexmedetomidine.52
More efficient analgesia/sedation, less hypotension, less need for vasoactive drugs but more bradycardia in dexmedetomidine group.52
A prospective randomised study considered morphine to be a reasonable alternative to haloperidol.52
Known effect on postoperative cognition: careful interpretation of this finding is necessary due to its anticholinergic effects.52
Incidence of postcardiotomy delirium 50% compared with 3% in dexmedetomidine group.52
|
Remifentanil |
Delirium evidence significantly higher in remifentanil group, possibly due to untreated pain after drug withdrawal.53
No difference concerning time to extubation, length of ICU or hospital stay and postoperative complications including haemodynamic side effects.53
|
Steroids | Dexamethasone |
|