Delirium

Definition and prevalence

Delirium is defined as a sudden and severe change in mental status, characterised by confusion, altered consciousness and difficulties with attention and cognition. [1,2] It is an acute, fluctuating condition that can develop quickly, often within hours or days, and its severity can change throughout the day. [3,4] Delirium can present in three forms: hyperactive (agitation, restlessness), hypoactive (lethargy, reduced motor activity), or mixed, where symptoms alternate between hyperactive and hypoactive states. [1,2]

In palliative care settings, delirium is highly prevalent, affecting up to 88% of patients before death. [1,2] This high prevalence is attributed to numerous risk factors and complex medical conditions, including older age, male gender, pre-existing cognitive impairment, organ failure (such as liver dysfunction), dehydration, electrolyte imbalances, infections and the use of certain medications such as opioids and drugs with anticholinergic properties. [1,4,5]

Assessment

Accurate and regular reassessment is vital, as delirium symptoms can change rapidly. Continuous monitoring allows for timely adjustments to treatment plans, ensuring that patients receive the most appropriate care throughout their palliative journey. [1,2]

Incorporating both clinical assessments and patient- and caregiver-reported experiences is crucial. This approach ensures a comprehensive understanding of the patient’s condition, with the latter capturing details that standardised tools might miss, especially in diverse cultural contexts. [3] Combining clinical tools with caregiver reports enhances diagnostic accuracy and tailors interventions to individual needs. [6]

The Confusion Assessment Method (CAM) and its variants, such as the CAM-ICU, are widely used tools that diagnose delirium by identifying acute onset, fluctuating course, inattention, and either disorganised thinking or altered consciousness. [1,2] These tools help distinguish delirium from other conditions like dementia and depression. [3,5,6]

Other assessment tools include the Delirium Rating Scale-Revised-98 (DRS-R-98), which evaluates delirium severity and tracks changes over time, and the Nursing Delirium Screening Scale (Nu-DESC), which is simpler and designed for daily use by nurses. [2,4] The Memorial Delirium Assessment Scale (MDAS) is also used to assess severity and monitor treatment response. [1,3] The 4AT is a short screening tool which can be used to detect delirium when applied as part of clinical routine. [7]

Terminal restlessness, a severe form of delirium occurring near the end of life, must also be assessed. This condition is characterised by agitation, confusion and distress and can significantly impact the patient's and their family's experience. [1,2] Recognising terminal restlessness requires attentive observation and the use of specific tools like the Richmond Agitation-Sedation Scale (RASS) to measure agitation levels and guide management. [3,4]

Non-pharmacological treatment

Non-pharmacological treatments can assist in managing delirium by addressing underlying causes and creating a supportive environment. Reorientation techniques, such as regularly reminding patients of the time, place and identity of people around them, can reduce confusion and help patients stay oriented. [3,6] Simple measures like using clocks, calendars and clear signage are effective in maintaining orientation. [3,6] Environmental modifications, including reducing noise levels, ensuring adequate lighting and minimising unnecessary stimulation, help decrease agitation and confusion. [1,2] Personalising the patient’s space with familiar objects and photos provides comfort and reduces anxiety. [2,4]

Addressing reversible factors is another essential aspect of non-pharmacological management. This involves treating underlying conditions that may contribute to delirium, such as ensuring proper hydration, correcting electrolyte imbalances and managing infections promptly. [1,3] Regular assessment and management of pain, constipation, urinary retention and other discomforts are crucial to prevent the exacerbation of delirium symptoms. [3,6] Cognitive stimulation activities, like engaging in conversation, listening to music or involving patients in simple tasks help maintain cognitive function and reduce the severity of delirium. [2,4] Gentle physical activities, such as short walks or light exercises, can also be beneficial. [2,4] Additionally, family involvement is critical in non-pharmacological management. Educating and supporting family members to understand and manage delirium symptoms can improve outcomes and provide reassurance to both patients and family carers. [3,8] Encouraging family presence and involvement in care activities enhances the patient’s sense of security and orientation. [1,3]

Pharmacological treatment

Pharmacological treatments may be required for managing delirium in palliative care, particularly when non-pharmacological interventions are insufficient. Antipsychotics are commonly used to manage the symptoms of delirium. Haloperidol is often considered the first-line treatment due to its effectiveness in reducing agitation and psychotic symptoms, as well as the availability of parenteral route administration (subcutaneous). [9,10] Second-generation antipsychotics, such as risperidone, olanzapine and quetiapine, are also used and may have a more favourable side effect profile, particularly regarding extrapyramidal symptoms. [1,9]

Sedatives like benzodiazepines are typically reserved for cases where delirium is related to alcohol or benzodiazepine withdrawal, as they can exacerbate delirium in other contexts. [1,3] However, in cases of severe agitation where other medications are ineffective, short-term use of benzodiazepines, such as oxazepam and lorazepam, or midazolam if oral administration is not possible, may be considered. [4,10]

Another medication used in the management of delirium is dexmedetomidine, particularly in intensive care settings. It has sedative and anxiolytic properties and can be useful for patients who require sedation but need to remain responsive. [9] Historically its use has been typically limited to specific critical care settings due to the perceived need for close monitoring of cardiovascular side effects, however there is emerging interest for its use in palliative care settings (particularly given evidence suggesting successful use via subcutaneous route). [9,11]

Phenobarbital is sometimes considered for patients with refractory delirium when other treatments [11] fail. It provides sedation and has anticonvulsant properties, making it useful in cases involving seizures and other complex issues. [10] However, it requires careful monitoring due to the risk of respiratory depression and other significant side effects. [1,10]

Other pharmacological agents (including melatonin, antidepressants, acetylcholinesterase inhibitors, and opioids) have also been utilised for the treatment of delirium, however the choice of pharmacological treatment should be tailored to the individual patient’s needs, considering factors such as the underlying cause of delirium, patient comorbidities and potential side effects of the medications. [2,4,12] Regular reassessment and adjustment of treatment plans are necessary to ensure optimal management and minimise adverse effects. [1,3] Overall, while pharmacological treatments are crucial, they should be used in conjunction with non-pharmacological strategies to provide comprehensive care for patients experiencing delirium in palliative settings. [3,6]

Equity and access

Equity and access to delirium care in palliative settings are influenced by various social and structural determinants, significantly impacting specific populations. Socioeconomic status plays a critical role, as patients from lower-income backgrounds often struggle to access high-quality healthcare and specialist delirium management services. [1,3] These patients may also face challenges in accessing continuous care, leading to underdiagnosis and undertreatment of delirium, which can exacerbate the condition and negatively impact their quality of life. [1,3]

Cultural and linguistic diversity further complicates access to delirium care. Patients from diverse cultural backgrounds may have different understandings of delirium and may encounter language barriers that hinder effective communication with healthcare providers. [13,14] For Indigenous populations, culturally sensitive approaches that respect traditional practices and incorporate community-based care models are essential to providing effective delirium management. [15] Similarly, individuals identifying as LGBTQI+ often face stigma and discrimination in healthcare settings, which can deter them from seeking care and result in inadequate management of delirium. [16] Ensuring inclusive and respectful care is vital for these populations to receive appropriate and effective delirium treatment. [16]

Geographical location is another significant factor affecting access to delirium care. Patients in rural and remote areas often face substantial barriers to accessing specialist palliative care services, including those for delirium. [17,18] Telemedicine has been suggested as a solution to these challenges, providing remote access to specialists and essential treatments. [13,17] However, telemedicine's effectiveness depends on the availability of technological infrastructure and digital literacy, which are often lacking in rural areas. [17,19] Additionally, people living in prisons face unique challenges in accessing delirium care due to the stressful and restrictive environment, which can exacerbate mental health issues and complicate management. [20,21] Addressing these disparities requires tailored approaches and policies that ensure equitable access to high-quality delirium care for all patients, regardless of their background or location. [1,3]

Care context

In aged care settings, the high prevalence of comorbidities and polypharmacy among elderly patients complicates the diagnosis and treatment of delirium. [2,4] Polypharmacy increases the risk of drug interactions and adverse effects, making careful medication management crucial. [1,4] Staff in aged care facilities must be trained to recognise and respond to early signs of delirium using tools like the CAM to ensure timely intervention. [1,2]

In dementia care, distinguishing between delirium and dementia symptoms is particularly challenging due to overlapping symptoms. [1,3] Delirium often presents as a sudden worsening of cognitive functions in patients living with dementia, requiring vigilant monitoring for behavioural and mental status changes. [3,8] Involving family members in the assessment process is critical, as they can provide insights into the patient’s baseline cognitive function and detect subtle changes indicating delirium or terminal restlessness. [3,8]

In paediatric care, delirium is often under-recognised and under-treated due to a lack of specific assessment tools and guidelines tailored for children. [1,22] Paediatric patients may present with atypical symptoms, making it essential for healthcare providers to be trained in recognising and managing delirium in children. [1,22] The management of paediatric delirium is similar to the approach for adults whereby non-pharmacological interventions are first considered, followed by the use of antipsychotics risperidone or haloperidol, which will be dependent on the most favourable drug profile. [22]

For non-cancer conditions such as heart failure or COPD, managing delirium involves addressing the underlying disease processes contributing to cognitive disturbances. A multidisciplinary approach is essential, incorporating input from various healthcare professionals to develop comprehensive care plans addressing both physical and cognitive aspects. [1,2] In cancer care, delirium is common due to the disease itself, its treatments and associated factors like pain and medication side effects. [3,4] Oncology patients require proactive management, including regular screening and addressing reversible causes such as infections, metabolic imbalances and medication effects. [2,6] Involving oncology specialists, palliative care teams, and family members ensures comprehensive management and support for both patients and caregivers. [1,3]

Implications for families and carers

Delirium significantly impacts families and carers, adding stress and emotional burden to their caregiving responsibilities. Families often find it distressing to see their loved ones confused and agitated, which can exacerbate their own anxiety and feelings of helplessness. [3,8] Providing families with education about delirium, including its causes, symptoms, and management strategies, can help alleviate some of this distress and empower them to support their loved ones effectively. [1,8]

Effective communication between healthcare providers and families is crucial. Regular updates about the patient's condition, changes in symptoms and the care plan can help families feel more involved and informed. [3,6] This involvement can improve the overall management of delirium by ensuring that family members can assist in monitoring symptoms and implementing non-pharmacological interventions, such as reorientation techniques and environmental modifications. [3,4]

Support for carers should also include emotional and psychological support. Delirium can be a frightening and confusing experience for both patients and their families, so providing access to counselling services, support groups and respite care is essential. [3,8] These resources can help carers manage their stress and maintain their own well-being, which is crucial for sustaining their ability to provide care. [1,6]