UMEM Educational Pearls

Category: Neurology

Title: Frontal Lobe Epilepsy

Keywords: frontal lobe epilepsy, epilepsy, seizure, partical focal seizure, complex focal seizure (PubMed Search)

Posted: 3/3/2010 by Aisha Liferidge, MD (Updated: 12/3/2022)
Click here to contact Aisha Liferidge, MD

  • Frontal Lobe Epilepsy (FLE) is characterized by recurrent, brief, focal seizures arising from the frontal lobe of the brain, often occuring during sleep.
  • FLE is the second most common form of epilepsy, behind Temporal Lobe Epilepsy (TLE).
  • FLE presents in 2 forms:  (1) simple partial (focal) seizures (no affect on awareness or memory), or (2) complex partial (focal) seizures (affects awareness and memory before, during, and/or after the seizure).
  • FLE seizures are often misdiagnosed as psychiatric disorders, non-epileptic convulsions, or sleep disorders, due to the unusual symptoms that they often produce.

Category: Critical Care

Title: Vent Strategies for TBI

Posted: 3/2/2010 by Mike Winters, MD (Updated: 12/3/2022)
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Ventilating the Patient with Traumatic Brain Injury

  • Many patients with acute TBI will require intubation and mechanical ventilation for a variety of reasons.
  • Ventilating the patient with TBI becomes a balancing act between maintaining adequate cerebral perfusion and minimizing lung injury.
  • Some pearls to consider:
    • Avoid hypoxia: although guidelines recommend a PaO2 > 60 mm Hg, most suggest a higher PaO2 (> 80 mm Hg) be initially targeted.
    • Avoid hypercapnia:  many patients will develop hypercapnia when ventilated using the low tidal volume strategy (6 ml/kg) of the ARDSnet trial; titrate TVs to maintain a PaCO2 between 32-35 mm Hg.
    • PEEP: the application of PEEP remains controversial in patients with TBI given the theoretical risk of increasing ICP through reductions in venous return; if PEEP is applied pay close attention to the cerebral perfusion pressure to ensure it remains > 60 mm Hg.

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Category: Pediatrics

Title: cephalohematoma

Posted: 2/27/2010 by Rose Chasm, MD (Updated: 3/6/2010)
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  • a collection of blood UNDER the periosteum of the outer surface of the skull
  • occurs in 2.5% of live births
  • most commonly occurs ove the parietal bones
  • because the blood is below the periosteum, it will NOT cross suture lines
  • usually enlarge during the first few days of life, then slowly resolve over weeks or months
  • significant bleeding is a risk
  • when the blood resorbs, it can aggravate neonatal jaundice
  • aspiration and xrays are not routinely indicated

Category: Orthopedics

Title: Segond Fracture

Keywords: Segond Fracture (PubMed Search)

Posted: 2/27/2010 by Michael Bond, MD (Updated: 12/3/2022)
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The Segond Fracture:

An benign appearing avulsion fracture of the lateral tibeal plateau that is marker for more significant injuries such as:

  1. Anterior Cruciate Ligament (ACL) tear associated with this fracture 75-100% of the time
  2. Injury to the Medial Meniscus occurs with a Segond fracture 66-75% of the time.

If this avulsion fracture is seen consider immobilzing the patients knee until they can follow up with Orthopedics and/or get an MRI to determine if additional injuries are present.

 


Category: Pediatrics

Title: Precedex for Peds

Keywords: Pediatrics, Sedation (PubMed Search)

Posted: 2/27/2010 by Reginald Brown, MD (Updated: 12/3/2022)
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Precedex (Dexmedetomidine) - Great for pediatric imaging procedures

Alpha-2 agonist with sedative properties

No analgesic effect alone, but shown to decrease the amount of opioids required for a painful procedure

Benefits pts go to sleep and awake in a more natural state.  Caregivers tend to prefer this as opposed to other sedatives.  Short recovery time- about 30 minutes

Adverse effects include bradycardia and hypotension.  Not recommended in any child with cardiac abnormalities.  Paradoxical hypertension with loading dose has also been observed

Effective for MRI or CT scans at loading doses of 2mcg/kg over ten minutes, then maintenance of 1mcg/kg/hr

Residents can gain experience with Precedex with Peds sedation on M,W,F mornings with sedation team, contact me to arrange a time for you to participate.


Category: Neurology

Title: Further Validation of Stroke Prediction Tool (ABCD2 Score)

Keywords: ABCD, ABCD2, California Rule, stroke, TIA, prediction tool (PubMed Search)

Posted: 2/24/2010 by Aisha Liferidge, MD (Updated: 12/3/2022)
Click here to contact Aisha Liferidge, MD

  • The 7-day risk of completed ischemic stroke after TIA is 5%.
  • The use of reliable stroke prediction tools are potentially invaluable in guiding the degree of urgency that one applies to the management of TIA patients.
  • Accuracy of the ABCD2 Score, considered to be the most-refined tool of its kind, was recently again evaluated.
  • This 7-point scale assigns risk based on 5 factors: Age > 60 (1 pt.), BP > = 140/90 (1 pt), Clinical features - weakness (2 pts), speech impairment w/o weakness (1 pt); Duration  >=60 min (2 pts), 59 to 10 min (1 pt); Diabetes (1 pt).
  • The study found that the discriminatory power of the ABCD2 Score may best be applied when used in patients at low risk for an early, disabling ischemic stroke.     

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Category: Critical Care

Title: Hyperglycemia

Posted: 2/22/2010 by Evadne Marcolini, MD (Emailed: 2/23/2010) (Updated: 2/23/2010)
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There have been several attempts to try to quantify the best target glucose levels in critically ill patients.  This is still a moving target, but a recent study sheds some light on the effect of different levels of hyperglycemia and the types of patients who are particularly vulnerable.

This is a retrospective cohort study whic reviewed 259,000 ICU admissions over a three year period at 173 separate sites.  Their findings were as follows:

Compared with normoglycemic patients, the adjusted odds for mean glucose 111-145, 146-199, 200-300, and >300 was 1.31, 1.82, 2.13 and 2.85 respectively.

There is a clear association between the adjusted odds of mortality related to hyperglycemia in patients with AMI, arrhythmia, unstable angina, pulmonary embolism, pneumonia and gastrointestinal bleed.

Hyperglycemia associated with increased mortality was independent of type of ICU, length of stay and/or pre-existing diabetes.

So, even though we have not come to solid conclusions about how far down to keep the glucose levels down, it makes sense to pay particular attention and be more vigilant of the blood glucose levels, especially in the higher-risk patients  listed above. 

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Category: Vascular

Title: Suspect Aortic Dissection-Don't Wait to Start the Drip!

Keywords: Aortic Dissection (PubMed Search)

Posted: 2/22/2010 by Rob Rogers, MD (Updated: 12/3/2022)
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Suspect your patient has an aortic dissection? Don't wait to lower the blood pressure.

A few considerations for the patient with suspected aortic dissection:

  • If the patient is hypertensive AND you really think they could have the disease, start the drip then. Don't wait until the CT is done. Every second that goes by with extremely elevated BP may increase the dissection length.
  • If you are really worried about a patient having a proximal aortic dissection, don't wait for the creatinine to come back...scan them without it. If you are really suspicious this is justified in many cases.
  • There is very little (to no) role in performing a dry CT (because the patient's creatinine comes back elevated). Dry CT is very insensitive. Instead get a transesophageal echo or an MRI. 

Category: Cardiology

Title: Herbal products and cardiovascular effects

Keywords: herbal, warfarin, adverse drug effects, drug effects, drug side effects, bleeding (PubMed Search)

Posted: 2/21/2010 by Amal Mattu, MD (Updated: 12/3/2022)
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Many cardiac patients take warfarin...no surprise.
Many patients use herbal supplements...no surprise.
Many herbal supplements can produce increased bleeding risk with warfarin, and some produce decreased effects of warfarin...that may be a bit of a surprise. Here's a few that are worth knowing:

Herbals that increase the bleeding risk of warfarin: alfalfa, angelica (dong quai), bilberry, fenugreek, garlic, ginger, and ginkgo

Herbals that decrease the effect of warfarin: ginseng, green tea

In addition to asking your patients about their prescription medications, specifically ask your patients if they take herbal supplements, over-the-counter products, or green tea (since many patients don't consider green tea to be either an herbal supplement)...especially if the patient takes warfarin. You just might diagnose or prevent a disastrous bleeding complication.

[Tachjian A, Maria V, Jahangir A. Use of herbal products and potential interactions in patients with cardiovascular diseases. J Am Coll Cardiol 2010;55:515-525.]


Category: Orthopedics

Title: Spine CT Scans

Keywords: Spine, Fracture, Diagnosis (PubMed Search)

Posted: 2/20/2010 by Michael Bond, MD
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A recent study by Smith et al showed that the general abdomen/pelvic CT scan in trauma patients obtained with 5mm slices is a better screening test for spine fractures than plain films. They also showed that when compared to dedicated reconstructed thoracolumbar CT scan (2mm slices focused on the spine) it did not miss any clinically significant fractures.

The statistic for plain radiographs and the nonreconstructive CT scan are shown below.

 
Plain Radiographs
Nonreconstructive CT Scan
 
Lumbar
Thoracic
Lumbar
Thoracic
Sensitivity % [95% CI]
47 [33 to 62]
13 [3 to 32]
94 [83 to 99]
73 [50 to 89]
Specificity % [95%  CI]
91 [78 to 97]
71 [54 to 85]
95 [85 to 99]
94 [79 to 99]
Positive Predictive Value % [95% CI]
85 [66 to 96]
15 [2 to 45]
95 [86 to 99]
89 [67 to 99]
Negative Predictive Value % [95% CI]
61 [48 to 72]
56 [41 to 71]
93 [82 to 99]
83 [66 to 93]

The take home point is that dedicated Spine CT scans are probably not needed unless they are going to be used to guide surgical or non-surgical management, and plain films should probably be abandoned in patients that are undergoing CT scans of the chest/abdomen/pelvis.

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Category: Toxicology

Title: Rodenticides

Keywords: cholecalciferol, brodifacoum (PubMed Search)

Posted: 2/18/2010 by Fermin Barrueto, MD (Updated: 12/3/2022)
Click here to contact Fermin Barrueto, MD

When a child is reported to be exposed to a rat poison it is commonly a long acting coumarin like brodifacoum. The rat usually eats the poison then during its traumatic little life will cause its own death by jumping and squeezing through a crack. When a human is exposed, this is the typical sequence of events:

  1. Exposure (and when you usually see them in the ED)
  2. 24-72 hrs later you will actually see an INR rise if actually ingested

Treatment is the same as for coumadin, vitamin K. However, do not start empirically since the patient will be committed to high doses of vitamin K for several months. Let the patient prove they have been poisoned which means they will require recheck of their INR 2-3 days later though they can be sent home with specific warning signs of anticoagulation.


Category: Neurology

Title: New-onset Seizure in AIDS Patients

Keywords: seizure, new-onset seizure, AIDS, HIV, HIV/AIDS (PubMed Search)

Posted: 2/17/2010 by Aisha Liferidge, MD
Click here to contact Aisha Liferidge, MD

  • For many years the recommendations for managing new-onset seizure (NOS) in the emergency department did not include any specific instruction for such patients with HIV/AIDS.
  • A study done by Pesola and colleagues found that, infact, AIDS patients with NOS require additional vigilence in terms of their management.
  • This study found that over 15% of AIDS patients with NOS would have erroneously been sent home without appropriate treatment had the standard recommendation for NOS management been followed; these patients were found to have intracranial lesions related to toxoplosmosis and lymphoma, and did not necessarily have focal neurologic deficits.
  • It is therefore recommended that all AIDS patients with NOS undergo neuroimaging with lumbar puncture, as indicated.

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Category: Vascular

Title: Bleeding Dialysis Fistulas

Posted: 2/15/2010 by Rob Rogers, MD (Updated: 12/3/2022)
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Bleeding Dialysis Fistula?

Ever see a patient in the ED c/o "my fistula won't stop bleeding"? If you haven't, you probably will in the future.

Here are some helpful tips on getting these bad boys to stop oozing:

  • Local pressure for 10 minutes will stop many of these bleeders
  • Can also try locally applied gel foam/thrombin
  • Pharmacologic adjuncts may be required, especially if the patient has missed dialysis-DDAVP can be given (makes platelets stickier by causing endothelial cells to release von Willibrand Factor). You can also give platelets, since platelets don't work well in a uremic state. Many dialysis patients are on coumadin because of chronic line clots, so don't forget to reverse this if present
  • Probably as a last resort you can tie a superficial circular suture at the puncture site. This works quite well.

Impingement Syndrome and the Diagnostic Accuracy of 5 Common Tests

It is also reported that subacromial impingement syndrome (SAIS) is the more frequent cause of shoulder pain.

The authors of this study attempted to determine the diagnostic accuracy of the following 5 tests for SAIS:

  • Hawkins-Kennedy
  • Neer
  • Empty Can
  • Painful Arc
  • External Resistance

The study demonstrated that any 3 positive tests out of the 5 has a sensitivity of 0.75 (0.54-0.96) , specificity of 0.74 (0.61-0.88), positive likelihood ratio of 2.93 (1.60-5.36) and negative likelihood ratio of 0.34 (0.14-0.80).  See the table below for the individual test characteristics.  No single test was deemed accurate enough to make the diagnosis by itself.

 

 

 

 

 

 

 

 

 

So in the end you should be familiar with most of these tests in order to use a combination of them to make the diagnosis of impingement syndrome.  Future pearls will review how to perform these tests.

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Category: Neurology

Title: Frostbite-related Neuropathy

Keywords: frostbite, neuropathy, hyperbaric oxygen (PubMed Search)

Posted: 2/11/2010 by Aisha Liferidge, MD (Updated: 12/3/2022)
Click here to contact Aisha Liferidge, MD

  • Given the recent extremely cold winter weather experienced in some parts of the country, we will likely be expected to recognize and treat true frostbite and its sequelae at an increasing rate.
  • Frostbite is the result of focal injury that follows the crystallization of water within subcutaneous tissue when exposed to low temperatures. 
  • Sequelae such as chronic neuropathic pain syndromes can results in up to 25% of patients with frostbite due to microvascular damage.
  • Hyperbaric oxygen has been shown to effectively treat this sequelae, even if administered in a delayed fashion, and should be considered as a viable therapeutic option.

 

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Category: Toxicology

Title: Transplant Med Toxicology

Keywords: transplant, tacrolimus, sirolimus, cyclosporine (PubMed Search)

Posted: 2/9/2010 by Bryan Hayes, PharmD (Emailed: 2/11/2010) (Updated: 2/11/2010)
Click here to contact Bryan Hayes, PharmD

With all of the post-transplant patients we see in the ED, a refresher on the toxicities associated with the most common immunosuppressant medications is warranted.

 

Cyclosporine (Sandimmune® and Neoral®/Gengraf®) and tacrolimus (Prograf®) are both calcineurin inhibitors that inhibit activation and proliferation of T-lymphocytes and IL-2.

-          Major concerns: Nephrotoxicity, drug interactions (CYP3A4)

-          Adverse Effects:

o       Electrolyte abnormalities: ­K+, ¯Mg+, ­glucose

o       CNS: HA, tremor (statistically higher with tacrolimus)

o       CV: HTN, ­ lipids (increased with cyclosporine)

o       End organ: hepatotoxicity, nephrotoxicity

o       Cosmetic (cyclosporine specific): hirsutism, gingival hyperplasia, acne

 

Sirolimus/Rapamycin (Rapamune®) is an M-tor inhibitor that inhibits T-lymphocyte activation and proliferation.

-          Major concerns: Drug interactions (CYP3A4)

-          Adverse Effects:

o       Delayed wound healing

o       Leucopenia, thrombocytopenia

o       Hypercholesterolemia


Category: Critical Care

Title: Hypocalcemia

Posted: 2/3/2010 by Evadne Marcolini, MD (Emailed: 2/9/2010) (Updated: 12/3/2022)
Click here to contact Evadne Marcolini, MD

  • Total body calcium consists of about half biologically active (ionized) and half inactive (80% bound to albumin and 20% to other ions)
  • hypocalcemia caused by hypoalbuminemia is physiologically insignificant, and correction factors are not accurate or reliable
  • The best way to measure true active calcium is to order an ionized calcium level

There are several conditions that alter ionized calcium levels, including:

  • alkalosis (increases binding to albumin)
  • gas bubbles in the sample (false lowering of calcium)
  • anticoagulants (must be collected in a red top tube)
  • blood transfusions (binding to citrate)
  • cardiopulmonary bypass
  • drugs (aminoglycosides, cimetidine, heparin, theophylline)
  • fat embolism
  • hypomagnesemia (correcting mg levels may preclude need for Ca repletion)
  • pancreatitis (several mechanisms, poor prognosis)
  • renal insufficiency (impaired phosphate retention)
  • sepsis

The bottom line is to measure ionized calcium, and consider all other factors that can be contributing to hypocalcemia in addition to repleting it. 

 

Altered Mental Status-Does Your Patient Have Non-Convulsive Status Epilepticus?


Ever intubated a patient in status epilepticus and wondered if they were still seizing after sedation and paralysis? Ever taken care of an altered patient and wondered if you should consult neurology and attempt to get an EEG?

NCSE is defined as continuous seizure activity without obvious outward manifestations of a seizure. This is important for emergency physicians to consider because it has to be detected early to prevent morbidity and mortality.


When to consider NCSE:

  • Prolonged postictal period
  • Unexplained altered mental status in a patient with a history of seizures
  • Altered mental status associated with "eye twitching" or blinking
  • Stroke patient who clinically looks worse than expected

Category: Orthopedics

Title: Scaphoid Fractures

Keywords: Scaphoid, Fracture (PubMed Search)

Posted: 2/6/2010 by Michael Bond, MD
Click here to contact Michael Bond, MD

Scaphoid Fractures:

For suspected scaphoid fractures with negative radiographs it is common practice to put a person in a short arm thumb spica splint until followup up radiographs can be obtained in 10-14 days.

However, there is evidence that a short arm thumb spica splint is not enough for people that have a true scaphoid fracture.  Gellman et al demonstrated that long arm thumb-spica cast immobilization for six weeks followed by short arm thumb-spica cast immobilization decreased time to union by 25% when compared to short arm thumb-spica casting alone.

The theory is that the short arm splint still allows for forearm rotation that can cause shearing motion of the volar radiocarpal ligaments.  A long arm splint prevents this shearing action.  The disadvantage of a long arm splint though is potential elbow joint stiffness and muscle atrophy that can occur during the prolonged period of immobilization.

So for your next patient with a scaphoid fracture seen on radiographs place them in a long arm thumb spica splint.

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Category: Toxicology

Title: Broad spectrum antibiotics for multidrug resistant bacteria

Keywords: antibiotics, imipenem, meropenem, doripenem, ertapenem, colistin, amikacin, multiresistant (PubMed Search)

Posted: 2/4/2010 by Ellen Lemkin, MD, PharmD
Click here to contact Ellen Lemkin, MD, PharmD

CARBAPENENEMS

  • Broadest spectrum of activity of all classes
  • Imipenem has slightly better gm + activity; lowers seizure threshold
  • Meropenem has slightly better gm - activity
  • Ertapenem does not cover Pseudomonas
  • Doripenem has the most activity against Pseudomonas
  • May use in PCN allergic patients (cross reactivity lower than previously thought)

TIGECYCLINE

  • Has broad coverage, but does not cover Pseudomonas
  • Bacteriostatic; derivative of tetracycline
  • Does NOT require renal dosing
  • Higher mortality in VAP than other agents; do not use for intra-abdominal infections (poss higher risk of perforation)

AMIKACIN

  • Has antipseudomonal activity
  • Used in combination with other agents for MDR (multi-drug resistant) bacteria
  • Causes nephrotoxicity and ototoxicity

COLISTIN

  • Bacteriocidal against many MDR gram - bacteria
  • Not active against Proteus, Provincia, Burkholderia, Neisseria, or Serratia
  • Nephrotoxicity and ototoxicity reported

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