Case Study: Solve A Neurologic Mystery

This is a case study involving an elderly female with complex medical history who presented with altered mental status of unclear etiology. The patient in this case is unable to give a history. Specialties Critical Case Study

Updated:  

There are no reliable sources who witnessed the events leading to patient presentation making it more difficult to ascertain the etiology of her condition. The author hopes to elicit a discussion of her case among peers in critical care nursing.

Background / Social History

RS is a 70-year-old female who lives independently in a first-floor apartment in the city. She has no close relatives but has neighbors who know her very well and check in on her from time to time. She hires a cleaning lady that does her house cleaning and laundry every week. Her nearest relative is a niece who lives in the same state but is 8 hours away by car.

Past History

Her medical history includes anxiety disorder, hypertension, hyperlipidemia, COPD, and mild kidney insufficiency.

She has a 40 pack/year history of smoking.

She has no known allergies.

Medications

  • Paroxetine 20 mg daily
  • Lorazepam 1 mg daily as needed for anxiety
  • Losartan 100 mg daily
  • Amlodipine 10 mg daily
  • Simvastatin 40 mg daily
  • Tiotropium 18 mcg inhaled daily
  • Albuterol MDI 2 puffs 4 times a day as needed

Present History / CC

On the day of her ED admission, her niece had been calling her phone and had been unable to get hold of her. Her niece called a neighbor who stated that she has not seen RS in 3 days. Concerned about RS's condition, the neighbor knocked on her door and heard no response. Luckily she was able to open the door as it was unlocked. Upon entering the living room, the neighbor found RS lying unconscious on the floor. She had frothy secretions from her mouth and had urinated on herself. She immediately called 911. She was intubated at the scene by EMS responders for airway protection due to her altered mental status.

Vital Signs

  • BP 180/100
  • HR 110
  • RR 32
  • T 38.5 C
  • O2sat 88% on RA prior to intubation

Diagnostic Studies

  • In the ED, RS pertinent labs showed a WBC of 15,000 mm3, a lactate of 2.5 mmol/L, and CPK of 20,000 U/L. Neurologic exam was significant for agitation and inability to follow commands with sedation wean. She was hyperreflexic with increased muscle tone. She is moving all her extremities equally and has no abnormal pupillary response. She is sedated on Propofol. CV exam reveals sinus tachycardia with BP of 110/50, her skin is warm to touch. Respiratory exam reveals rhonchi in upper lung fields with moderate white secretions via ET tube
  • ABG: 7.36, 38, 82, 19, -3, 100% on ACVC: 16X400, FiO2 of 0.5 PEEP of 5.
  • CXR reveals mild cardiomegaly, a hyperinflated lung silhouette and mild RLL opacity.
  • Non-contrast CT Scan of her brain showed focal vasogenic edema in the basal ganglia.

The remainder of the exam revealed normal findings.

The ED was particularly busy that evening so RS was immediately transferred out to ICU without further testing in the ED. Because of her complex medical condition, she was transferred to the MICU under your care as her primary RN.

What thoughts run in your head that could possibly explain what caused RS's presentation?

What further testing would you anticipate?

How would you care for RS as her nurse?

For this exercise to be fun and informative, answer in the following manner:

  1. List possible explanations you would expect to hear from her medical team that could explain her neurologic presentation and why.
  2. Tests you would anticipate.
  3. Interventions you would provide as the bedside nurse and why.

Note: This is an actual case and the outcome is already established.

Specializes in ICU.

Ooh! I'll try to!

1. List possible explanations you would expect to hear from her medical team that could explain her neurologic presentation and why.

ALOC could be due to poor oxygenation from pre-existing lung issues plus possible onset of pneumonia. She probably some lyte imbalance d/t hyprreflexia present. There could also be a UTI present since she have elevated WBCs (although she could be plain septic too?) which is associated with ALOC in older people. Possible rhabdomylosis and/or MI which affected her cardiac output and maybe caused her to fall over and loss consciousness. Consider possible drug overdose since she was on paxil so there is a history of depression and social history seems to indicate some social isolation.

2. Tests you would anticipate.

U/A, CBC and lytes, cardiac enzymes, EKG

3. Interventions you would provide as the bedside nurse and why.

Turn q 2, elevate HOB, insert Foley, measure I&Os, administer ABX, monitor oxygen status and suction as needed, monitor heart rhythms, IVF, neuro checks q 4-6 hours

CVA or head injury secondary to a fall? Need CT with contrast or MRI. X-rays of head and neck. Neuro checks q 1. Check for other fall related injuries. Administer ABX for pneumonia and continue all other respiratory interventions and monitoring but get her extubated and off mechanical ventilation ASAP. Difficult to get a proper neuro eval while sedated. Monitor lactate, electrolytes, chem panel, CBC daily. Pro BNP? Consult renal guys and pulmonology. Monitor cardiac continuously.

Not and ICU nurse but I'm a psych nurse... Thought I'd give this a shot.

1. List possible explanations you would expect to hear from her medical team that could explain her neurologic presentation and why.

First thought was neuro malignant syndrome - (Psych patient, increased CPK, hyperthermia, tachycardia, tachypnea, rigidity, altered LOC.) Patient had a seizure, fell, aspirated and got pneumonia. Incontinence is common when patients have a seizure.

2. Tests you would anticipate.

Tox Screen, CT scan, ABG, Liver Enzymes, Blood Sugar

Would need to cooridnate with OP providers to see if there have been med changes recently (doses increased/decreased, new meds)

Possible LP to rule out meningitis

3. Interventions you would provide as the bedside nurse and why

ABC's, Cooling blankets, anticipate the use of antibiotics for pneumonia, IVF, Sodium Bicarb, Chemical/ Physical restraints related to Alterered LOC and agitation. Monitor closely, when restarting psych meds as it was probably due to one of these drugs that caused NMS.

Serotonin syndrome and NMS are very similar. Can't say off the top of my head what the difference is, but my gut is saying that this is NMS.

Specializes in Critical Care, ED, Cath lab, CTPAC,Trauma.

The possibilities are broad....

The patient fell and hit her head causing an altered LOC and possible seizure. Couldn't get up and laid on the floor causing rhabdo with the greatly elevated CPK with possible aspiration pneumonia

OR she developed an inflammatory muscle disorder from the Simvastatin causing her CPK's to elevate develop muscle weaknesses, renal failure and fell and developed acidosis/electrolyte imbalance causing seizure and poss aspiration PNA. But that wouldn't account for her increased muscle tone

Ooooo!!! I like neuroleptic malignant syndrome and paxil

CBC, lytes, Chem 27 profile, LFT, Bun Creat, LFT's, Tox scereen, PAN culture, blood culture, amylase, lipase, Ammonia level.

Sedate, hydrate, ventilate.

These answers are very cool. Learning a lot.

The suspense is KILLIN me!! LOL

Specializes in ACNP-BC, Adult Critical Care, Cardiology.

Thanks for all the responses and I loved all your input. If you were in our ICU team, you would all get stars. One thing to realize in cases like this is that given the paucity of available information on the patient, one would not easily arrive at a single etiology. That’s the thrill of being in healthcare because you get to play Sherlock Homes. A systematic way of differential diagnoses is what physicians employ. In our ICU team, rounds consist of analyzing these differentials and everyone’s input is considered. Nurses MUST be present on rounds and always participate.

Everyone touched on very important considerations in a patient who presents with altered mental status. Metabolic/endocrine, medication/toxicities, infectious, trauma, CNS sources, hypoperfusion states (cardiogenic, sepsis) must be ruled out. These are very broad as many of you already realized. Great thinking on all your part for mentioning all these etiologies.

Kudos to the ones who mentioned the possibility of a seizure. Her presentation at the scene does depict a post-ictal state (frothy saliva, urinary incontinence, unresponsiveness) though she has no history of seizure disorder. The question is why she had one. Her head CT Scan was not very specific and her neurologic symptoms were difficult to pin to a clear pattern of lesion from a stroke.

She had signs of an infectious process with an elevated WBC and fever. The ED team was worried about meningitis and started meningeal doses of antibiotics despite absence of reliable signs of nuchal rigidity, Kernig’s or Budzinski’s sign. Unfortunately, the ideal situation of performing an LP first was not done. However, other cultures from her blood and urine were sent before initiation of antibiotics.

Her CXR findings weren’t quite convincing for full blown aspiration pneumonia though there isn’t a doubt that she could have aspirated and may have aspiration pneumonitis. Her antibiotic regimen would have covered this if present as she was started on a broad spectrum antibiotic combo.

You guys are very smart for invoking Serotonin Syndrome. Based on her symptom cluster and medication profile, this was one of the leading differentials entertained in her case. Paroxetine as many of you know is a Selective Serotonin Reuptake Inhibitor used in anxiety and depressive disorders. Serotonin Syndrome is a condition associated with increased serotonergic activity in the CNS. It can occur with therapeutic SSRI use, SSRI interaction if used concomitantly with many culprit medications, and intentional self-poisoning with an SSRI agent.

Physical exam findings in Serotonin Syndrome includes: hyperthermia, agitation, ocular clonus, tremor, akathisia, hyperreflexia, inducible or spontaneous clonus, muscle rigidity, Babinski’s sign, dry mucus membranes and flushed skin. Many of these were noted on this patient. Serotonin Syndrome is diagnosed based on exam findings and the Hunter Criteria has been used which can be found here. This patient had hyperthermia, hyperreflexia, and muscle rigidity. Various providers had conflicting exam findings of clonus in her case. One mentioned that this was noted in the ED but was not seen in subsequent physical exams. Serotonin Syndrome is also associated with metabolic acidosis and rhabomyolysis though this patient had other reasons to present with these lab findings.

At any rate, we wanted to rule out meningitis and other structural etiologies in her brain. An LP has to be done so that we can de-escalate her antibiotics if we rule meningitis out. Her CSF did not reveal numbers consistent with meningitis. We then performed an MRI of the brain which revealed a finding we have not thought of before. It showed symmetrical white matter edema in the previously identified basal ganglia and posterior cerebral circulation consistent with...

posterior-reversible.pdf

This diagnosis made a lot of sense – PRES is associated with a seizure of acute onset and is a type of encephalopathy that leads to altered mental status and even coma in extreme cases. This interesting condition has only been discussed in case reports in the literature since 1996. The clinical syndrome is described as an insidious onset of headache, confusion or decreased level of consciousness, visual changes, and seizures, which was associated with characteristic neuroimaging findings of posterior cerebral white matter edema. Hypertensive disorders, renal disease, and immunosuppressive therapies are risk factors for this disorder.

PRES can develop in patients with acute elevation of blood pressure. The mechanism is felt to be due to a breakdown in cerebrovascular autoregulation. Brain blood vessels contrict and dilate accordingly based on changes in blood pressure to allow a constant flow of blood. As the upper limit of cerebral autoregulation is exceeded such as what could happen in acute hypertensive states, vessels dilate causing hypoperfusion and extravasation of blood into the brain parenchyma, hence the edema.

The condition can be reversible in a period of days to weeks. The goal of treatment is to maintain normotensive state. It is not clear what level of blood pressure elevation is high enough to cause PRES. It is thought that an acute blood pressure elevation that is significantly higher than baseline could result in this condition. Anticonvulsants are indicated and continued after resolution of the findings on brain imaging. MRI findings should improve at follow-up and a resolution of the findings further confirm this diagnosis.

This patient improved on Day 3 and was awake, following commands, and tolerating a spontaneous breathing trial on the ventilator. Her neurologic symptoms improved and she was extubated. She had a repeat MRI a few days later which showed resolution of the brain edema. While it’s still not clear if she had Serotonin Syndrome as well, the facility did get in touch with the State’s Poison Control hotline who felt that the concern for Serotonin Syndrome is low and that treatment was not necessary. Patient did recall missing doses of her meds including her antihypertensives which could have pushed her into a hypertensive crisis that was not detected at the time she was found. She recovered nicely from this hospitalization and was discharged home with 24-hour care.

This case makes me miss ICU. I loved rounds, because it was a whole team of people thinking about what is happening with the patient. The intensavists and nurses I worked with were Brilliant!!!!!

My first patient EVER in nursing school had PRES.

Specializes in Adult Internal Medicine.

Very interesting read, thanks for the presentation.

Specializes in Pediatric Pulmonology and Allergy.

thanks for posting the case denoument... very detailed and informative, with many elements I would not have thought of.

Specializes in ICU.

Very awesome case study to share with us. Please share more in the future!

Specializes in Med-surg.

I agree. Please do share more of these in the future! It's a great exercise in critical thinking.