MH | Cognitive Disorders

1. Delirium vs. Dementia: The Critical Distinction The most heavily tested concept is differentiating these two conditions.Delirium is an acute, rapid-onset syndrome characterized by an impaired, fluctuating level of consciousness. It is a temporary, reversible condition caused by underlying physiological issues like infections, drug toxicity, withdrawal, or metabolic imbalances.Dementia is a gradual, insidious, and progressive disease marked by cognitive decline. Crucially, the patient's level of consciousness remains intact.2. Delirium: Must-Know Clinical KnowledgeSafety Priority: Patients have poor judgment, sensory misperceptions (illusions and hallucinations), and unpredictable mood shifts. Protecting the patient from physical injury is the highest priority. Use restraints only as a last resort because they can increase agitation.Nursing Actions: Provide frequent reality orientation. Keep the environment well-lit and low-stimulus to minimize misperceptions and sensory overload. Validate the patient's fears, but never reinforce their hallucinations.Pharmacology: Treat the underlying cause first. Haloperidol may be used for severe agitation, while benzodiazepines should be avoided (except in alcohol withdrawal) because they can worsen delirium.3. Dementia: Must-Know Clinical KnowledgeCore Deficits: Remember the 4 A's: Amnesia (memory loss), Aphasia (language deterioration), Apraxia (loss of motor function execution), and Agnosia (inability to recognize objects).Types: Alzheimer's disease is the most common. Vascular dementia has an abrupt onset with a stepwise decline. Lewy Body dementia features prominent visual hallucinations. Frontotemporal dementia presents early with drastic personality changes.Nursing Actions: Establish familiar, consistent daily routines to minimize demand on memory. Monitor basic physiological needs (nutrition, hydration, toileting), as patients eventually lose the ability to perceive internal cues.Caregiver Strain: Caring for dementia patients causes severe exhaustion. Assessing caregivers for role strain and referring them to support groups or respite care is a major nursing responsibility.4. Must-Know MedicationsCholinesterase Inhibitors (Donepezil, Rivastigmine, Galantamine) and NMDA Antagonists (Memantine) temporarily slow disease progression but are not cures. Monitor for GI bleeding, nausea, and diarrhea. Newer IV infusions (Lecanemab, Donanemab) target beta-amyloid plaques but are not first-line.Safety Red Flag: Antipsychotics used to manage dementia-related psychosis carry a black box warning due to an increased mortality risk in older adults.5. Must-Know Therapeutic CommunicationEarly Dementia: Use reminiscence therapy (recalling past events). It is highly effective for boosting self-esteem because remote memory stays intact longer than recent memory. Provide single-step instructions.Severe Dementia: Do not use reality orientation if it causes the patient distress. Instead, use:Distraction: Shift their attention to a neutral activity.Going Along: Reassure the patient without correcting their delusion.