Hospital-acquired delirium

Confusion in the hospital is extremely common. Roughly 50%1 of hospitalized patient’s experience delirium, frequently increases to 80% if in the ICU. About a third of delirious patients go unrecognized primarily because they are hypoactive which means instead of agitated and acting-out they are more withdrawn into themselves and thus easier to miss.

It must be stated up front that delirium is NOT the same thing as dementia. Delirium is a sudden change in thinking, generally over hours to days, that occurs as a result of another causative factor. Dementia is the steady irreversible decline in brain function over months to years. I have seen numerous families informed the patient “developed dementia” in the hospital; which is inaccurate.

Having seen thousands of delirious patients recognition can be straightforward. Just like a family member knows there is someone wrong, just not sure what. Generally, a confused, inattentive patient, unsure of time and circumstances is delirious.

The standard validated way to diagnosis delirium is know as the Confusion Assessment Method (CAM).

  • Diagnosis: Acute onset and fluctuating course & Inattention and either disorganized thinking or altered level of consciousness

How to identify delirium?

  1. New (acute) – it’s a new change and fluctuates. Not chronic thinking problems (ie: dementia).
  2. Inattention – generally first sign. Before disorientation develops. You have to redirect or get attention mid conversation. Or the patient while listening to you keeps missing parts of the conversation.
  3. Variable – it’s coming and going. Can be as short as during a single conversation. Waves and wanes over hours to days.
  4. Altered level of consciousness – lethargic, hard to awaken, hyperactive, easily startled. Not their normal level of wakefulness.
  5. Disorganized thinking pattern – rambling thoughts, illogical statements, not connecting the dots, jumping back and forth between current topic and something unrelated.
  6. Disoriented – can’t answer simple questions like: what is your name and birthdate? Where are you? What years is it? How did you get here?
  7. Memory impairment – forgetting things mid-interview; ask the same questions over and over.
  8. Perception disturbances – hallucinations – seeing things/people who aren’t there; thinking there are bugs on the walls or crawling on their skin.
  9. Psychomotor alterations –
    • hyperactive: restless, fidgety, can’t sit still, picking at clothes, IV tubing, whatever their hands find.
    • hypoactive – sluggish, staring off into space, abnormally slow in speech, thought or action.
  10. The above items are a validated way to diagnosis delirium. Known as Confusion Assessment Method (CAM).
    • Diagnosis: Acute onset and fluctuating course & Inattention and either disorganized thinking or altered level of consciousness

What causes delirium? In short: the hospital. A great irony of healthcare is that people come to hospitals to get better and a multitude of factors come together to cause harm.

There are many risk factors which contribute to delirium in the hospital. Examples include (in roughly descending order of risk):

  1. Medications Side Effects & Drug-Drug Interactions (ie: polyphamacy).
    • This is the biggest cause of iatrogenic (medical care caused problem) delirium. So many medications we prescribe cause confusion as a side effect. Every medication has to be weighed for its likelihood to help vs risk it will harm.
    • Commons culprit medications:
      • Opioid pain medications: morphine, oxycodone, hydrocodone, Dilaudid (hydromorphone), fentanyl, to less extent tramadol
      • Benzodiazepines: Xanax (alprazolam), Valium (diazepam), Ativan (lorazepam), Versed (midazolam), Klonipin (clonazepam), Ambien (zolpiden), Librium; the list goes on
      • Anticholinergic: these medications have many different roles but all work through a similar pathway. Benadryl, phenergan, compazine, meclizine, hydroxyzine, Bentyl.
      • Neuropathy medications: Neurontin (gabapentin), Lyrica (pregabalin), amitriptyline, nortriptyline
      • Mental health medications: excluding most SSRIs (Prozac, Lexapro, Zoloft, etc) and SSNRIs (Effexor, Cymbalta) near everything prescribed for mental health treatment has the potential to cause confusion. They are a mixed bag. These can both greatly improve but also greatly worsening delirium. This is where an experienced hospitalist really must make subtle judgement calls regarding medications. 
  2. Pre-existing cognitive impairment.
    • Dementia being most prominent. A patient with underlying dementia is very likely to become more confused in the hospital. One not need have “full” dementia. Mild dementia, impaired cognitive function, easy to get confused/overwhelmed or forgetful all increases the risk. It is a spectrum; the more difficulty your brain has doing day to day task the higher proportional chance it will not work well (ie: confused / delirious) when subjected to extra stress.
    • Mental Health Disorders – same underlying idea as above. Mild symptoms do not impair daily functioning. If the brain has severe mental health disorders at baseline there is a good possibility the hospital will exacerbate.
  3. Dehydration – this once can be easy to fall into and easy to overlook. Older people have many risk factors: often don’t eat or drink as much, told to avoid fluid intake due to heart, liver or kidney condition, are taking fluid pills (diuretics), not have ready access to food water if mobility is impaired, have brain problems preventing them from eating/drinking (dementia, stroke, MS, etc). To exacerbate this further as fluid intake goes down, the kidneys work less. This causes both natural toxins built up and less removal of normal medications so that their levels build up and become toxic; even when taking a normal dose.
    • “Lights on but nobody is home” This is how I best describe dehydration on an elderly mind. Often they are awake but tend to blankly stare; can respond to questions but are either slow to process, get lost in speaking or no response at all. Quietly staring at wall or looking around is common.
    • Electrolyte problems and need for indwelling urinary catheter (Foley) – I’ll lump these together as they often go hand in hand.
  4. Disruption of normal sleep cycle / circadian rhythm – One of the largest, most under appreciated causes and a primary SOLUTION to hospital acquired delirium.
    • If you are reading this in a hospital it is probable you haven’t had good sleep lately. Effects of illness, medications side effects, noise, lab draws, staff interruptions, unrelenting beeping of your IV pump.
    • At some point most of us have had to perform at work/school on little to no sleep. Remember how sluggish, irritable and scattered your concentration was? Now age your brain, make yourself sick, add in jet-lag from changing the circadian rhythm and sprinkle in some medication side effects. Delirium seems almost inevitable.
    • This is a personal pet-peeve of mine in the hospital. Not taking the need for recuperative sleep seriously and then being surprised when confusion develops.

Delirium is bad for you. Pick any health metric: length of hospital stay, risk of falls, time to recover, medication needed for behavior, risk of death (25-33% mortality rate), discharged not home (ie: skilled nursing facility), risk of readmission; everything gets worse with delirium. 

Delirium Prevention and Treatment:

Like most things, an ounce of prevention is worth a pound of cure; this is highly applicable. 

  1. SLEEP, SLEEP, SLEEP – nothing is more important to fixing a delirious brain than good quality sleep. Its absence is a primary cause and rarely does one improve without it.
    1. The hospital seems almost designed to interrupt sleep. Constant noise, light, staff members, testing, procedures, medical conditions and medication side effects come together to ruin sleep in a hospitalized patient. 
    2. Our brains heal during sleep. Specifically deep sleep (N3 – Slow Wave Sleep). Sleep cycles take 90-120 mins to complete; they repeat throughout the night until morning awakening. N3 (Deep Sleep) occurs about 60-90 mins after falling asleep. Light sleep (N1 & N2) can easily be awoken from; deep sleep not easily. In a hospital frequent stimuli awaken people (they may not even realize it) and either pause or reset their sleep progression. This means after just a few days in the hospital having spent minimal time in deep sleep your brain working as if you haven’t slept in days. Imagine trying to learn a new task or triage tons of new information having not slept in days. Now make your brain older, out of its familiar environment, under the influence of medications you may have never had before dealing with new possibly life-changing information.
    3. Naps – short naps, < 30 mins, are OK. Long naps are to be avoided as they disrupt the circadian sleep cycle leading to people being awake more at night which further worsens delirium. 
    4. See section on Sleep for more details.
  2. Medications – as outline above many of the medications we use have negative impacts on the patient’s mental state. The more we use the worse it becomes. Limiting as much as possible is necessary to improve delirium
  3. Environmental changes – environmental changes both contribute and help alleviate delirium. Positive changes include:
    1. Reinforce circadian rhythms – during the day lights on, shades open (sunlight is important; going outside if able is great), out of bed in a chair, doing something mentally stimulating (reading, word search, crossword). Watching TV OK but because so passive does not maintain alertness. 
    2. Ensure have glasses and hearing aids (battery dead?) so can process environment.
    3. Redirection / Reorientation – as they start to mentally stray redirect them with correct information.
      1. Don’t argue with patients. If delirium has progressed to the point they are argumentative a more convincing argument won’t work. Redirect the conversational elsewhere or just dismiss and move on. 
  4. GET OUT OF THE HOSPITAL – not surprisingly if the hospital is making the patient worse the sooner they get out the better. Waiting for delirium to resolve to go home is ill-advised. Staying longer to “fix” delirium usually makes it worse for the reasons cited above. It is the physician judgement when the balance of medical stability and delirium warrants discharge.
    1. About half of patients with hospital-acquired delirium will leave the hospital still delirious to some degree
    2. Home is best for the patient. They need familiar environment and familiar faces.
    3. Transition to rehab can increase delirium because of the change in environment. If discharge to rehab is medically advisable having family at the rehab facility as much as possible for the first few days to aid in transition can significantly help. 
  1. THINGS NOT TO DO:
    • Staying hospitalized longer than medically necessary
    • Using medications with potentially offending side effects when other options exist.
    • Staying up late or ignoring the importance of sleep.
    • Keeping hospital lighting the same level of light 24 hours/day.
    • Staying in bed all day watching TV.
    • Not having glasses / hearing aids.
    • Arguing with the delirious patient.
    • Not working with staff to mobilize out of bed.
    • Thinking head imaging is helpful. Delirium is not a structural problem; it’s not a stroke. Head CTs (and brain MRIs) are normal in delirium. Family members often ask for “brain scans” thinking it will “show something” and be helpful. If concerned discuss with the doctor.
    • Restraints – when a patient is so combative they become a danger to themselves they can be placed in restraints. These are fabric shackles to the wrist/ ankles tying them to the bed. I hate them. They are undignified and often make things worse. Imaging trying to wake from a dream tied to the bed; you’d freak out too. They are unfortunately sometimes necessary; however, as little use as possible is always the goal.

References:

  1. Al Farsi RS, Al Alawi AM, Al Huraizi AR, Al-Saadi T, Al-Hamadani N, Al Zeedy K, Al-Maqbali JS. Delirium in Medically Hospitalized Patients: Prevalence, Recognition and Risk Factors: A Prospective Cohort Study. J Clin Med. 2023 Jun 7;12(12):3897. doi: 10.3390/jcm12123897. PMID: 37373591; PMCID: PMC10299512. https://pmc.ncbi.nlm.nih.gov/articles/PMC10299512/