UMEM Educational Pearls

There are numerous different causes of pediatric hemorrhagic diarrhea. Consider a pediatric patient with bloody diarrhea as being at risk for developing hemolytic uremic syndrome. Most cases of hemolytic uremic syndrome are caused by O157:H7 strains of E Coli that release Shiga-like toxin from the gut. Systemic release of the toxin causes microvascular thromboses in the renal microvasculature. The characteristic microangiopathic hemolysis results with anemia, thrombocytopenia and peripheral schistocytes seen on laboratory studies, in addition to acute renal failure.

Antibiotics have been controversial in the treatment of pediatric hemorrhagic diarrhea due to concern that they worsen toxin release from children infected with E Coli O157:H7 and thus increase the risk of developing hemolytic uremic syndrome. Numerous previous studies have provided conflicting data regarding the true risk (1). A recent prospective study showed antibiotic treatment increases the risk (2). Most recommendations warn against using antibiotics to treat pediatric hemorrhagic diarrhea unless the patient is septic.

Bottom line: Avoid treating pediatric hemorrhagic diarrhea with antibiotics

Show References

When you prescribe certain medications, it may require some further instructions to avoid ethanol or a disulfiram like reaction (nausea, vomiting, flushing) may occur. Keep this short list in your brain:

1) Particular cephalosporins: cefotetan is a the one more likely

2) Nitrofurantoin

3) Sulfonylureas: chlorpropamide and tolbutamide

4) Metronidazole

5) Trimethoprim-sulfamethoxazole

Show References

Jolt accentuation, the exacerbation of a headache with horizontal rotation of the neck, or shaking of the stretcher in the less cooperative patient, has been promoted for the past few years as the "go-to" test to assess for meningeal irritation in patients with headache. Previous studies have quoted sensitivities as high as 97.1%. (1)

A new prospective study in AJEM challenges this belief by looking at a total of 230 patients with headaches and subsequent LPs. 197 of them had the jolt accentuation test done, which had a sensitivity of only 21% for pleocytosis (defined as greater than or equal to 5 cells/high power field in the 4th CSF tube). Kernig's and Brudzinski's signs both did even more poorly, with a sensitivity of 2% each. (2)

Show References

What is a massive transfusion?

• Can be institution dependent but usually means greater than 10 Units of blood products transfused within 24hrs.
• Most hospitals have this as a protocol that a physician can order to notify the blood bank that a large volume of blood products may be required rapidly.

When would I use this?

Indications:

-Systolic Blood pressure < 100

-Unable to obtain blood pressure

AND

-Penetrating torso trauma

-Positive FAST

-External blood loss

-Plans to go to the OR

How do I give it?

• The transfusion ratio is usually 1:1:1 or 2:1:1
• Give 1 unit PRBC, then 1 U FFP, and alternate until 6 units of each have been given and then 1 bag of apheresis platelets (6 equivalent units). Can repeat as needed.

Does this apply for just traumatic bleeding?

• Although this data was based on soldiers in the recent Iraq Wars, it has been used for medical patients as well.
• Therefore, consider using in upper GI bleeds, post-partum hemorrhage, etc.

Are there other agents I can use?

• There is some data to give tranexamic acid early (less than three hours from injury) in trauma patients who are hypotensive and are having severe bleeding.

What am I trying to do with this protocol?

• Control hemorrhage
• Use the best products possible
• Prevent hypothermia
• Prevent hemodilution
• Treat coagulopathy

Show References

Question

16 yo M with pleuritic right upper chest pain that started today.  He is suffering from an asthma exacerbation currently in the setting of URI with cough.  He is afebrile, tachycardic to 140-150s, respiratory rate 20, and sats 98% on room air.  ECG was performed which incidentally diagnosed this patient WPW and he went for ablation as an outpatient.  His chest x-ray showed:

Besides a bad day, what do we call this chest x-ray finding?

Show Answer

Show References

Attachments

1409221530_IMG_5821.jpg (1,850 Kb)

Tendon Lacerations:

• Flexor tendon lacerations have historically not been repaired by emergency providers due to the extensive pulley systems involved and possibility of loss of mobility from scarring.
  • However, if both ends of the tendon can be visualized in the ED it is not unreasonable to place 1 or 2 horizontal mattress sutures between the two ends to prevent retraction of the proximal portion which can make a formal repair more difficult.
  • These injuries have a very high complication rate so most will defer to a hand surgeon for definitive treatment.
• Extensor tendon lacerations can be repaired by emergency providers.
  • Most often these repairs are limited to 6-8. See image at http://www.boneandjoint.org.uk/content/focus/extensor-tendon-injury
  • One technique is to use a running horizontal mattress suture with non-absorbable nylon sutures. 
  • The ultimate strength of the repair is dependent on the number and size of the sutures placed.
  • Careful placement of the sutures can prevent gap formation between the ends when the tendon is stressed.
  • A good discussion on tendon repairs can be found at http://www.boneandjoint.org.uk/content/focus/extensor-tendon-injury

A reasonable approach to all tendon lacerations is to loosly reapproximate the wound and splint the hand in the position of function until the patient can be seen by a hand surgeon in the next 1-3 days.  These injuries do not require immediate surgical repair, and with the high rate of complications it is probably best to discuss with your hand surgeon before attempting a repair.

Show References

The NEXUS criteria is widely applied to adults who present with neck pain due to trauma.  While this study did include about 2000 pediatric patients, there were not enough young children to draw definitive conclusions.  For more information on the evaluation of the cervical spine, see Dr. Rice's pearl from 9/7/12.  A 2003 study piloted an algorithm for cervical spine clearance in children < 8 years.

Patients were spine immobilized if: unconscious, abnormal neurological exam, history of transient neurological symptoms, significant mechanism of injury, neck pain, focal neck tenderness or inability to assess based on distracting injury (extremity or facial fractures, open wound, thoracic injuries, or abdominal injuries), physical exam findings of neck trauma, unreliable exam due to substance abuse, significant trauma to the head or face, or inconsolable children.

When the 2 pathways (see attached) were implemented, there was a decrease in time to cervical spine clearance.  There were no missed injuries in the study period prior to implementation of the pathway or once it was implemented.  There was no significant difference in the amount of xrays, CT scans or MRIs.

Show References

Attachments

1409192317_Cspine_clearence_pathway.docx (52 Kb)

Food poisoning can occur with many different food groups/items, as well as how the food is prepared, handled or stored.

There are three specific “food poisonings” associated with fish consumption can cause serious toxicity/illness beyond GI symptoms: Ciguatera, Scrombroid, tetrodotoxin (puffer fish)

Ciguatera

• Endemic to warm tropical water and bottom reef dwelling large carnivorous fish: grouper, red snapper, barracuda, amberjack, parrot fish, etc. (> 500 species).
• Toxin: ciguatoxin: opens voltage gated Na channel
• Produced by dinoflagellates (gambierdiscus toxicus) and bioaccumulates in large fish through food chain (eating small fish).

Symptoms:

• GI symptoms: n/v/d and abdominal pain
• Hot/cold reversal
• Paresthesia of tongue/lip >> extremities
• Dental pain: “loose teeth”

May progress to develop…

• T wave changes, bradycardia, hypotension
• Respiratory paralysis and pulmonary edema

Treatment: supportive care and mannitol in presence of severe neurologic symptoms (limited evidence).

Scrombroid

• Endemic in (dark meat) fish living in temperate or tropical water: amberjack, skipjack, tuna, mackerel, albacore, mahi mahi, etc.
• Associated with poor refrigeration/storage after catching fish.
• Histidine in tissue is converted to histamine by bacteria on the fish skin.

Symptoms:

• GI symptoms: n/v/d and abdominal pain
• Upper body flushing
• Puritis, urticarial and perioral swelling can occur
• Palpitation and mild hypotension

Tx: H1/H2 blockers and supportive care

Serious reactions: treat like allergic/anaphylactic reaction

Tetrodotoxin

• Ingestion of improperly prepared puffer fish (fugu) sushi (or bite from blue ring octopus)
• Toxin: tetrodotoxin: blocks voltage gated Na channel.
• Highest concentration in liver and ovary.

Symptoms:

• GI: n/v/d
• Progressive paresthesia and weakness (bulbar-> extremities), ataxia
• Ascending paralysis and respiratory distress/paralysis
• Dysrythmia and hypotension
• Mental status preserved.

Treatment: supportive care and intubated if needed.

While sitting on an international flight, ever wonder what your risks are for a blood clot?

General Background:

It is estimated that the risk for a deep venous thrombosis (DVT) is 3-12% on a long-haul flight. However, the real incidence is difficult to evaluate, due in part to the lack of consensus about 1) diagnostic tests, and 2) the appropriate time frame to relate a venous thromboembolic event (VTE) to travel.

Risks Factors for VTEs on long-haul flights:

• General:
  • stasis: prolonged sitting & crowded conditions
  • relative hypoxia
  • dehydration

• Patient specific:
  • Age >40
  • Female gender
  • Use of estrogen-containing contraceptives/hormone replacement therapy
  • Obesity
  • Varicose veins in the legs
  • Family/personal history of prior VTEs
  • Active cancer/recent cancer treatment

Bottom Line:

• Even healthy individuals are at risk on long-haul (>8 hour) flights.
• The risk increases the longer the flight
• Current data does not appear to show a risk difference between economy and business class.
• Avoid dehydration and immobility
  • Exercise your legs/calf muscles
  • Drink plenty of fluid

Show References

Infectious Risks Associated with TTM

• Targeted temperature management (TTM) is commonly used in the care of patients resuscitated from cardiac arrest.
• Despite improving neurologic outcomes, TTM can increase the risk of infection, bleeding, coagulopathy, arrhythmias, and electrolyte derangements.
• Infectious complications of TTM are associated with increases in ICU length of stay, along with increases in the duration of mechanical ventilation.
• Pneumonia and bacteremia are the two most common infectious complications of TTM, with S.aureus the most common single pathogen isolated in cases of infection.
• Since TTM may suppress normal signs of infection, it is important to be vigilant for these two infectious complications.
• At present, evidence does not support prophylactic antibiotics for all patients receiving TTM.

Show References

Question

Football player complains of sudden foot pain after begin tackled. What’s the diagnosis? 

Show Answer

Show References

Optimal Revascularization in Complex Coronary Artery Disease

- A multicenter trial 4,566 patients with NSTEMI, unstable angina, and multi-vessel coronary artery disease were enrolled comparing outcomes of cardiac stenting versus coronary artery bypass.

- Cardiac stenting was associated with improved outcomes and lower mortality in the following subgroups: age >65 years, women, unstable angina, TIMI score >4, and 2 vessel disease.

- Despite high clinical risk patients who underwent cardiac stenting compared to surgical revascularization did better in this prospective registry. 

Show References

Back pain accounts for more than 2.6 million visits

30% of ED patients receive X-rays as part of their evaluation

Imaging can be avoided in a majority of these patients by focusing on high risk (red flags)  findings in the history and physical exam.

Patients who can identify a an acute inciting event without direct trauma likely have a MSK source of pain.

Imaging rarely alters management

Attempt to avoid imaging in patients with nonspecific lower back pain of less than 6 weeks duration, with a normal neurologic exam and without high risk findings (fever, cancer, IVDA, bowel or bladder incontinence, age greater than 70, saddle anesthesia, etc)

Patients with radiculopathy (sciatica) and are otherwise similar to the above also do not require emergent imaging

• The human enterovirus D68 is a rare virus closely related to the rhinovirus which causes the common cold.  However, there have been recent outbreaks throughout the midwest and the areas are rapidly expanding.
• Mild symptom onset of rhinorrhea and cough rapidly progress to hypoxia and respiratory distress.
• Key features are the rapid progression, presence of wheezing even without a history of reactive airway disease, and typically an absence of consolidation on chest XR.
• Children under 5 years and those with asthma are at the greatest risk for respiratory failure.
• There are a limited number of labs in the US which test specifically for EV-D68. At UMMC, the Luminex respiratory virus panel can be ordered using the kit form which includes a flocked swab and viral transport media.  Unfortunately, the panel does not differentiate between the closely related enterovirus and rhinovirus. 
• There is no definitive cure, rather only supportive care and low-threshold for admission/observation for high risk patients.

Show References

Digoxin-specific antibody fragments (Fab) are safe and indicated in all patients with life-threatening dysrhythmias and an elevated digoxin concentration. However, full neutralizing doses of digoxin-Fab are expensive and may not be required (not to mention cumbersome to calculate).

Based on pharmacokinetic modeling and published data, a new review suggests a simpler, more stream-lined dosing scheme as follows:

• In imminent cardiac arrest, it may be justified to give a full neutralizing dose of digoxin-Fab.

• In acute poisoning, a bolus of 80 mg (2 vials), repeat if necessary, titrated against clinical effect, is likely to achieve equivalent benefits with much lower total doses.

• With chronic poisoning, it may be simplest to give 40 mg (1 vial) at a time and repeat after 60 min if there is no response.

Show References

Why is everyone obsessed about blood pressure management in stroke?

Greater than 60% of patients with stroke have elevated blood pressure, and 15% have a systolic blood pressure (SBP) greater than184 mmHg. That is more common in hemorrhagic stroke than ischemic stroke. 

Whether it's an acute hypertensive response or a premorbid uncontrolled hypertension, it is likely to negatively affect the clinical course and neurological outcome. 

Below is a suumary of the current guidelines for blood pressure management of stroke subtypes; for a more detailed summary of the guidelines, refer to the original article (below)

Ischemic stroke:

Lytic patients have a target SBP of <185mmHg, whereas nonlytic patients have a higher SBP target of <220mmHg

Hemorrhagic Stroke:

Non-aneurysmal hemorrhage patients with a SBP >180mmHg have a target SBP of <160 mmHg, whereas if their SBP was 150-220 mmHg then lowering it to 140 mmHg is safe. Patients with aneurysmal hemorrhage have a target SBP of <160mmHg

Show References

Goal-Directed Resuscitation During Cardiac Arrest

Focusing on high-quality CPR is by far one of the most effective methods to ensure your arrested patient has the best chance to survive.  However, emerging evidence suggests that there are additional goals that we should try and accomplish during our resuscitation.

 As we continue to move toward goal-directed resuscitation strategies, optimizing coronary perfusion pressure (CPP) may be our next target in “personalizing” the care we provide to those in cardiac arrest.

A recent AHA consensus statement recommended the following physiologic goals during cardiac arrest care:

• CPP > 20 mmHg: Estimated by diastolic BP [DBP] – [CVP] using an arterial line & central line.
• DBP > 25 mmHg: When an a-line is present without an appropriate CVC.
• EtCO₂ > 20 mmHg: When an a-line & CVC are not present.

Each of these variables can give the provider valuable feedback about how their patient is responding to their resuscitation.  Some argue that the DBP target should be much higher (>35 mmHg), with the caveat that pharmacologic optimization can only occur once high quality CPR is confirmed.  The goal should always be to minimize the use of epinephrine whenever possible!

Bottom Line:  During your next cardiac arrest resus, consider using a goal-directed strategy by monitoring the patient’s CPP, DBP, & EtCO₂ to determine the effectiveness of your resuscitation.

Suggested Reading

1. Meaney PA, Bobrow BJ, Mancini ME, et al. Cardiopulmonary resuscitation quality: [corrected] improving cardiac resuscitation outcomes both inside and outside the hospital: a consensus statement from the American Heart Association. Circulation. 2013;128(4):417-35.
2. Sutton RM, Friess SH, Maltese MR, et al. Hemodynamic-directed cardiopulmonary resuscitation during in-hospital cardiac arrest. Resuscitation. 2014;85(8):983-6.

Follow me on Twitter @JohnGreenwoodMD

Question

CXR shown below, what's the diagnosis? ...and name 3 differential diagnoses.

Show Answer

Show References

PARADIGM Shift in Heart Failure

- Angiotensin-converting enzymes inhibitors (ACE-I) are cornerstone for treatment of heart failure (HF) given the multiple trials which have shown their positive risk reduction in cardiovascular death.

- Studies looking at the effect of angiotensin-receptor blockers (ARBs) on mortality have been inconsistent; thus ARB's have been recommended as 2nd-line for those who have unacceptable side effects to ACE-I.

- A recent double-blinded RCT (PARADIGM-HF)  ~8400 patients with class II-IV HF w/ ejection fraction <40% were treated with enalapril (standard therapy) versus novel therapy with neprilysin (neutral endopeptidase) inhibitor combined with an ARB.

- Primary outcomes were death from cardiovascular causes and hospitalization for HF; The RCT was ceased early (~27 months) because of an overwhelming benefit with the new agent.

- At study closure death occurred 26.5% in the standard group versus 21.8% in the novel group. The risk of HF hospitalization was decreased 21% with novel therapy.

- In early studies the use of a neprilysin inhibitor combined with an ARB has shown superior effects to current standard therapy (ACE-I), however long-term effects of this novel therapy are yet to be determined. 

Show References

In May 2014, the U.S. Public Health Service released the first comprehensive clinical practice guidelines for PrEP.

Pre-Exposure Prophylaxis (PrEP) has been shown to decrease the risk of HIV infection in people who are at high risk by up to 92%, if taken consistently.

How this applies to the ED patient:

• You may start seeing more patients on only one HIV medication. The PrEP recommendation is once daily emtricitabine/tenofovir (Truvada) 200/300 mg. 
• This is not a therapy that should generally be initiated in the ED as close outpatient monitioring and follow up is essential.

For more information, the CDC has a comprehensive website dedicated to PrEP.

Show References