The DIMS Mnemonic In Fever and Altered Mental Status – “Best Case Ever 64 Salicylate Poisoning” – And Some Additional Resources

I just listened to Best Case Ever 64 Salicylate Poisoning, Dec 2017 [link is to the podcast and shownotes] from Emergency Medicine Cases.

The podcast and show notes above are an outstanding teaching resource and just need to be carefully reviewed.

Dr. Hans Rosenberg presents the case of a 59 year old man  brought into the emergency department with fever, diaphoresis, altered mental status (AMS).

And Dr. Rosenberg states that in patients with fever and AMS you want to consider the DIMS mnemonic. And he briefly discussed it.

In this post I review the DIMS mnemonic. And I used emedicine.medscape.com to review drugs that can cause AMS.

So DIMS represents:

  • Drugs-Overdose of prescription drugs, illicit drug toxicity, or withdrawl from drugs or illicit substances.
  • Infections-PUS, pneumonia, urinary, skin/soft tissue, CNS infection
  • Metabolic and Endocrine
    • altered pH, hypo/hyper Na+ Ca++, acute liver or renal failure, diabetic ketoacidosis
    • Endocrinopathies – hypo-/hyper-cortisol, hypoglycemia [a finger stick glucose is always your first move for altered mental status (along with the ABCs)], thyrotoxicosis
  • Structural (CNS)- brain injury, subdural hematoma, post-ictal, stroke, tumour, brain mets

So here are the differential diagnoses of drug toxidromes from emedicine.medscape.com the section on Anticholergic Toxicity [The list below is a very helpful set of links to most toxidromes]:

Differential Diagnoses [One toxidrome not on the list below is Serotonin Syndrome – See my post Serotonin Syndrome – Help From Emergency Physician Educators, Posted on August 14, 2017]

Anticholinergic Toxicity Updated: Oct 26, 2017

Diagnosis

No specific diagnostic studies exist for anticholinergic overdoses. Laboratory studies that may be helpful include the following:

  • Acetaminophen and salicylate screening – in all intentional poisonings
  • Blood and urine cultures – in febrile patients
  • Serum chemistry and electrolyte analysis
  • Electrolyte and arterial blood gas (ABG) analysis [Experts I follow suggest that a venous blood gas (VBG) is adequate.
  • Urine pregnancy test – in all women of childbearing age

Additional studies that may be useful are as follows:

  • CT of the head and MRI imaging – for patients in whom AMS is insufficiently explained by the ingested agent or who are unresponsive to appropriate intervention
  • ECG – for all patients with suspected toxic ingestions*
  • Lumbar puncture – for patients with fever and AMS in whom CNS infection is suspected as a possible etiology.

*Obtain an electrocardiogram (ECG) soon after ED arrival. Sinus tachycardia is common and does not require treatment in the stable patient. Consider administration of sodium bicarbonate to patients with signs of sodium channel blockade such as QRS prolongation (>100 milliseconds) or a terminal R wave in aVR >3 mm on the ECG.

 See Workup for more detail.

See Treatment and Medication for more detail.

Antihistamines also have anticholinergic properties. In 2015, the AAPCC documented 74,278 single exposures to antihistamines, with 31,966 specific to diphenhydramine. A total of 13 deaths were attributed to antihistamine toxicity, of which 10 were specifically diphenhydramine related.

Anticholinergic syndrome results from the inhibition of muscarinic cholinergic neurotransmission. Clinical manifestations are caused by CNS effects, peripheral nervous system effects, or both.

Remember common signs and symptoms with the mnemonic, “red as a beet, dry as a bone, blind as a bat, mad as a hatter, hot as a hare, and full as a flask.” The mnemonic refers to the symptoms of flushing, dry skin and mucous membranes, mydriasis with loss of accommodation, altered mental status (AMS), fever, and urinary retention, respectively.

Anticholinergic syndrome results from the inhibition of muscarinic cholinergic neurotransmission. Clinical manifestations are caused by CNS effects, peripheral nervous system effects, or both.

Remember common signs and symptoms with the mnemonic, “red as a beet, dry as a bone, blind as a bat, mad as a hatter, hot as a hare, and full as a flask.” The mnemonic refers to the symptoms of flushing, dry skin and mucous membranes, mydriasis with loss of accommodation, altered mental status (AMS), fever, and urinary retention, respectively.

Causes – This is a link to drugs that have anticholinergic properties and it is a long list.

In addition to anticholinergics, drug classes that have anticholinergic properties include antihistamines, antipsychotics, antispasmodics, cyclic antidepressants, and mydriatics. Furthermore, several varieties of plants and mushrooms contain anticholinergic substances.

 

And in a google search of the DIMS mnemonic I found an excellent site, Geri-EM: Personalized E-Learning in Geriatric Emergency Medicine. The page, Causes of Delirium, from the site has an excellent brief review of Causes of Delirium.

 

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