Delirium: Clinical sciences

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Introduction0:00–0:50

Delirium is a transient and reversible condition characterized by an acute change in consciousness and cognition, as well as a decreased ability to maintain or shift attention.
Delirium is usually seen in older patients, and is always associated with some underlying condition or trigger. The mnemonic “PINCH ME” can help you remember the most common causes of delirium, which include Pain, INfection, Constipation and urinary retention, Hydration, Medications and substances, and finally, Environmental triggers.
Now, if a patient presents with signs and symptoms suggestive of delirium, you should first perform an ABCDE assessment to determine if they are unstable or stable.If unstable, stabilize their airway, breathing, and circulation.

Unstable patient0:50–1:13

Next, obtain IV access, and, if needed, provide supplemental oxygen to maintain saturation above 90%. Finally, put your patient on continuous vital sign monitoring, including heart rate, blood pressure, and oxygen saturation.Now let's go back to the ABCDE assessment and discuss stable patients.

Stable patient1:13–2:50

First, perform a focused history and physical. Most often, patients are over 65 years old, and might have a history of neurologic conditions like dementia or Parkinson disease.
They may present with acute hallucinations, while family members or caregivers often report that the patient has been exhibiting unusual behavior.
Physical examination might reveal hyperactive delirium, with signs like agitation, restlessness, and combativeness. However, some patients might present with hypoactive delirium, with signs like drowsiness, apathy, withdrawal, or diminished speech.
Finally, some patients can have mixed delirium, switching between hyperactive and hypoactive signs throughout the day. No matter what type of delirium your patient has, keep in mind that these findings must represent an acute change from baseline, with a fluctuating course described as waxing and waning.
If that’s the case, you should suspect delirium.Now, here’s a clinical pearl to keep in mind! Delirium is a diagnosis of exclusion!
In other words, there are no laboratory or imaging methods that can confirm the diagnosis, so be sure and rule out other conditions that can mimic manifestations of delirium.
Ask about neurologic symptoms, such as slurred speech and new-onset weakness; and examine your patient for focal neurologic signs, such as expressive aphasia and hemiparesis because these findings are suggestive of an acute neurologic event.Now that you suspect delirium, you should confirm the diagnosis using a validated metric, such as the Confusion Assessment Method, or CAM.

Confusion Assessment Method2:50–3:24

Diagnosis requires the presence of an acute and fluctuating change in mental status, poor attention span, and evidence of either disrupted thought processes or alteration in consciousness.
If your patient doesn’t meet these criteria, the CAM is negative, so consider an alternative diagnosis. On the other hand, if the criteria are met, the CAM is positive, so you can diagnose delirium.Now that you’ve diagnosed delirium, the next step is to assess the patient's risk of harm to themselves and others.

Risk assessment3:24–5:14

Patients at low risk will generally present with hypoactive signs of delirium and should generally receive nonpharmacologic management.
This includes reducing the dose or discontinuing medications known to have CNS side effects, like opioids; as well as frequent mobilization; and orientation improvement, like providing a clock and calendar so they can keep track of the time and date.
Next, ensure proper nutrition and hydration; encourage good sleep hygiene; and minimize sensory deprivation with vision and hearing aids.
On the other hand, patients at high risk of harming themselves and others will generally display hyperactive signs of delirium.
These individuals could also try to remove catheters and tubes, and they might even try to leave the hospital. In this case, start with nonpharmacologic management, including redirection and extra staff attention like a one-to-one sitter.
Additionally, consider pharmacologic management with haloperidol or a second-generation antipsychotic, like olanzapine. Haloperidol is generally a preferred agent since it’s associated with lower risk of side effects, primarily hypotension and oversedation.
But, keep in mind that haloperidol is contraindicated in individuals with prolonged QT interval, or neurologic conditions like Parkinson disease and Lewy body dementia.After initiating management, you should assess the underlying cause.
Cover the most common causes of delirium using the PINCH ME mnemonic. To get started, order labs, including a CBC and CMP.
First, let’s start with Pain. These patients usually report severe pain, or have a potential source of pain, like recent surgery or trauma.

Pain5:14–5:52

Sometimes, your patient could present with hypoactive delirium and diminished speech. Look for indirect signs of pain, such as grimacing, clenching of the jaw, moaning and groaning, as well as guarding of the affected body part.
In this case, consider poorly controlled pain as a cause of delirium, and be sure to optimize pain control by adjusting doses or switching to alternative medications.Next up are INfections.

Infections5:52–6:59

In these individuals, history reveals fever and chills, typically in combination with more specific symptoms associated with the infectious source, like cough or dysuria.
On the other hand, physical exam might show abnormal lung sounds or suprapubic tenderness; while labs usually reveal leukocytosis.
At this point, you should suspect infection and order further testing to evaluate. This includes sputum or urine cultures, urinalysis, as well as imaging like a chest x-ray.
Next, follow up on the tests you’ve ordered. If the urinalysis shows WBCs, leukocyte esterase, and nitrites; and urine cultures are positive, then diagnose urinary tract infection and start appropriate antibiotics.
On the other hand, if the sputum culture is positive or the chest x-ray shows a new infiltrate or consolidation, diagnose pneumonia and start appropriate antibiotics.
Next up are Constipation and urinary retention.These are commonly overlooked causes of delirium, since they are usually associated with nonspecific history and physical exam findings.

Constipation/Urinary retention6:59–7:42

(Hx) History may include hard or infrequent stool, frequent small urine voids or symptoms of BPH, and history of medications known to cause constipation or urinary retention.
(PE) Physical exam may reveal fecal impaction or the presence of a functional disability. In these patients, consider constipation or urinary retention as potential triggers of delirium, so make sure to review the patient's medication list to stop any possible cause, and proceed with a bowel regimen or bladder catheterization.Moving on to Hydration.

Hydration7:42–8:12

Let’s suppose that your patient exhibits physical exam findings of dehydration, like dry mucous membranes, poor skin turgor; or labs show low sodium or calcium levels, or even high sodium or calcium levels.
These findings suggest dehydration and electrolyte imbalance as possible triggers for delirium, so optimize hydration and correct the underlying electrolyte imbalance.
Next up are Medications and substances. If your patient presents after recent use of alcohol or an illicit substance, order a serum alcohol level and a urine toxicology screen.

Medications/Substances8:12–9:44

Positive results are highly suggestive of delirium due to intoxication. The management includes supportive care and monitoring of the patient until the intoxication subsides.
On the other hand, if your patient presents with hypertension or tachycardia and has a history of long term alcohol or substance use, but no recent alcohol or substance use, suspect withdrawal syndrome, especially from alcohol or benzodiazepines.
Again order a serum alcohol level and urine toxicology screen. Negative results are highly suggestive of delirium due to withdrawal syndrome, rather than acute intoxication.
In this case, The management includes supportive care and monitoring of the patient until the withdrawal subsides, including giving benzodiazepines if delirium tremens is present.Now, some patients can have no history of recent or long-term alcohol or substance use, but have a positive history of use of medications with known CNS side effects, such as benzodiazepines, opiates, and anticholinergics.
These patients might have medication-induced delirium, so discontinue the causative medication, adjust dosing, or switch to an alternative option.
Finally, we have Environmental triggers! If your patient is in the ICU, has had recent major surgery, or has recently been administered anesthesia or sedation, consider environmental triggers as a cause of delirium.

Environment9:44–10:50

Management consists of creating a more structured environment, like reducing exposure to noise, improving daytime light and reducing night-time light, and promoting sleep.
Now here’s a clinical pearl! One important cause of delirium is azotemia, which is commonly seen in individuals with acute kidney injury.
These individuals usually present with elevated BUN and creatinine levels, as well as oliguria or anuria. Additionally, there could be a positive history of use of nephrotoxic medications, such as NSAIDs.Here’s another clinical pearl!
No matter what the underlying cause of delirium, once it’s been addressed, the patient should be monitored until they reach baseline mental status and receive the necessary supportive care measures.
Alright, as a quick recap… Delirium is a syndrome characterized by an acute change in attention, consciousness and cognition as well as a decreased ability to focus or to maintain or shift attention.

Review10:50–12:06

If you suspect delirium, use the Confusion Assessment Method to rule out or confirm the delirium. Once you diagnose delirium, assess the patient's risk of harm to themselves and others.
Patients at low risk require nonpharmacologic management, such as reducing or discontinuing medications with CNS side effects; frequent mobilization; orientation improvement; proper nutrition and hydration; as well as good sleep hygiene and minimizing sensory deprivation.
On the flip side, patients at risk of harm to themselves and others may require pharmacologic management with haloperidol or a second-generation antipsychotic.
Next, you should assess the underlying cause of delirium. Use the PINCH ME mnemonic to cover the most common causes, which include Pain, INfections, Constipation and urinary retention, Hydration, Medications and substances, and Environmental triggers.