3 thoughts on “Hot Seat Case #91: 17 yo F with altered mental status”

1. 
   

   Management will definitely depend on what level ED I’m in. I’d think about ABCDE’s and a SAMPLE history to make sure we weren’t dealing with opiate abuse on top of severe hyponatremia (water doping?), protect her airway (nasal trumpet and facemask at minimum if she is protecting her airway, intubation if she is not) and circulation (hypotensive but only weighs 40kg, and with normal heart rate- compensated shock vs adrenal suppression from chronic steroids related to her UC?).
   Her bedside sodium and seizure require emergent hypertonic saline until the seizure activity abates. Her head needs scanning regardless. Sepsis is on the differential too. Consider IV steroids….(and don’t forget the beta, tox screen and ekg….).

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2. 
   

   The presentation of agitation has a really wide differential and then takes an unexpected turn with the hyponatremia.
   To begin with, I will say that each of us will be fooled at least once by hypoxia as the cause of agitation. Start with the pulse ox reading, or if she is so agitated that this is not possible, consider an ABG. The respiratory exam looks for tachypnea, work of breathing, and focal findings, keeping a range of pulmonary problems from PE to pneumonia to severe asthma in mind. The other immediate issue is to check the bedside glucose, since hypoglycemia causes a range of behavioral changes from lethargy to shakiness to confusion/agitation. Of course, this bedside glucose would have gotten me to the hyponatremia, which was not necessarily expected but is on the short list of metabolic derangements that cause mental status changes.
   After the immediate first step of checking for hypoxia and hypoglycaemia, I would continue with my ddx.
   Under metabolic concerns, bedside testing of glu, Na, and acidosis are needed.
   Ingestion: given the age and history of depression, there is reason to be concerned about drug use. Her pupil size may not be helpful after ketamine and Versed, since I think they cause opposite effects on pupillary size. Thinking about an anticholinergic ingestion,she is not tachycardia, dry, or hyperthermic. Same for thinking about amphetamines. K2, PCP, street ketamine can cause mental status changes, though her heart rate is not as high as expected for these ingestions. Vitamin D excess can cause severe headaches, though not sure about the range of symptoms. But I would keep this ingestion in mind.
   Thinking of intracranial causes, a stroke or a venous thrombosis can cause changes in mental status without necessarily causing focal deficits on exam. If it is warm weather, viral encephalitis can lead to confusion and slowing of mentation. Finally, autoimmune conditions include SLE and anti-NMDA receptor encephalitis.
   In ED: CBC, CMP, bedside labs, serum osmolarity, ASA, APA, Utox, Uhcg, head CT without contrast. A resident or you stay with her to monitor her VS– her heart rate is lower than expected for agitation. If these don’t lead to an answer, then an LP is next.

   Then the seizure occurs and hyponatremia/hypochloremia are identified.
   Treat: 3% NS
   Send: urine for Na, Cr, Osms.
   Why does she have such low Na? Water intoxication; SIADH from CNS infections/pressure; water retention if she is in renal failure, but she is not edematous on exam; increased colostomy output, though would expect bicarb to be low.

   I look forward to learning more.

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3. 
   

   I agree with Maybelle’s initial approach with focused history and assessment of ABCs.
   At first, this seems like a case of a teen with AMS, albeit one with an underlying medical condition.
   For those who like mnemonics, here is a good one for AMS ddx.
   A Alcohol
   E Epilepsy, Electrolytes, and Encephalopathy
   I Insulin (hypoglycemia)
   O Opiates and Oxygen
   U Uremia
   T Trauma and Temperature
   I Infection
   P Poisons and Psychogenic
   S Shock, Stroke, Subarachnoid Hemorrhage and Space-Occupying Lesion

   In this teen who required > 6 mg/kg (!!!!!) IM ketamine for agitation, I’d be very worried about an organic cause or recreational drug use.

   This patient should be a medical alert as she may need ongoing sedation, and further sedation would almost certainly require intubation. I’d make sure my team was aware of the fact that we are very close to intubation, prep equipment, and have med nurses draw meds etc but as described would not do so yet. She should be placed on nasal ETCO2 monitor.
   I would want to get a glucose and VBG w lytes asap, as well as sending CBC,CMP, ETOH, ASA, Tylenol (acute Tylenol ingestion would not cause this, just to r/o co-ingestant). I’d want a Utox and hcg, but would not stop the immediate approach to cath her for it. She doesn’t clearly fit any toxidrome, and all that ketamine and midaz are going to cloud that picture anyway.

   She definitely needs an EKG for toxin effect, as well as a stat head CT r/o bleed/edema and lower in ddx, mass).

   Her BP is low especially in light of the reported amount of ketamine she received, and I’d bolus her with NS pending labs.

   If her glucose and Istat result OK, her rhythm looks sinus on the monitor, her BP is not worsening, and her airway is adequately protected, I’d scan her ASAP after getting IV access established and a bolus running.

   In this case, the profound hyponatremia is the most likely cause of her AMS/agitation and seizure. Once that Na result returns, she needs hypertonic saline 3% at 3 ml/kg for her symptomatic hyponatremia.

   Once the seizure stops, I’d think hard about why she’s so hyponatremic. More hx is key at this point. Assign someone to talk to the parents. Has she had vomiting or excess ostomy output (hyponatremic dehydration)? Drinking a ton of water (psychogenic or DI)? Fatigued or weird hyperpigmentation (Addison’s/adrenal failure)? Out at a last night “at a friend’s house” [rave] (MDMA aka Ecstasy, which causes hyponatremia as well as thirst/water intoxication)? Does she smell like alcohol (is this pseudohyponatremia from unmeasured osmole)? Trying to lose weight (diuretic abuse)?

   I’d also be ordering a serum osm, cortisol, TSH. Now she definitely needs a Foley, and urine osm, Na, Cr (as well as that Hcg and Utox from before).

   Though her K is normal, if she is hypotensive, has been on steroids anytime recently, or looks like she has a suntan (bronze hyperpigmentation from Addison’s) I’d give stress dose hydrocortisone also.

   At this point, I’d also be calling my ICU and renal colleagues…

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