Pseudoaxiom – epinephrine in the digits

By Will Fleischman, MD

Please refer to SMARTEM

Axiomnoun – A statement or proposition that is regarded as being established, accepted, or self-evidently true. Pseudoaxiom – A false axiom passed down as anecdote, tradition, or simple repetition from one generation of medical providers to the next.

Literature commonly cited to support epinephrine as dangerous:

  1. Garlock, 1931. 4 cases of gangrene following digital blocks with NO epinephrine; concludes gangrene was probably due to mechanical injury from the tourniquet used.
  2.  Kaufman, 1941. Case report of  a pt who developed gangrene following digital block of procaine/epinephrine for I&D of a felon. Buto pt soaked digit in boiling boric acid solution following the surgery.
  3. McLaughlin, 1942. Case similar to above, pt also soaked finger in hot boric acid solution while finger was still anesthetized and developed severe blistering.
  4. O’neil, 1944. 8 cases of finger gangrene following digital anesthesia; all cases that used epinephrine involved hot water soaks followed by finger blistering.
  5. Bradfield, 1963. Literature review, concludes that there is no significant association between epi and gangrene

 

Later literature showing no harm from epinephrine:

  1. Burnham, 1958. Case series, 93 digital blocks with epi without complications.
  2. Latimer & Kay, 1991. Injected own toes and fingers w/epinephrine and noted mild pallor followed by vasodilation and warmth.
  3. Wilhelmi, 1998. Case series, 23 digital blocks with epinephrine without complications.
  4. Sylaidis, 1998. Case series of 100 digital blocks with epi; dopplers showed never more than 40% reduction in flow.
  5. Denkler, 2001.  Systematic review, concludes no evidence against using epinephrine.
  6. Wilhelmi, 2001. Double-blind RCT, 60 digital blocks, half with epi. Epi group had less bleeding, less re-dosing of local anesthesia, quicker procedure. No adverse effects in either group.

 

Keep in mind that the half life of epinephrine injected systemically is 3-5 minutes (hence the dosing in ACLS protocols), and approx. 10-15 minutes in the tissues. In contrast, BP tourniquets are accepted as safe when inflated for 2-3 hours during surgical procedures of the upper extremities. In contrast, BP tourniquets are accepted as safe when inflated for 2-3 hours during surgical procedures of the upper extremities.

Conclusion: it is safe, and in many cases beneficial, to use epinephrine in digital anesthesia.

Post Test Here

 

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ACS Updates

By Amy Sanghvi, MD

Please refer to EMRAP

Updated UA on NSTEMI guidelines.

Focused update from Guidelines from 2007.

Done to focus on new issues relative to antiplatelet medications:

Ticagralor and Prasugrel (Effient).

Many using Prasugrel instead of clopidogrel. P2Y12 receptor inhibitors.

Thianopyridines.

Some patients have a genetic resistance to clopidogrel.

The new agents slightly better at preventing MI and maybe death. Also work faster than clopidogrel (Hours v 30 min.) However, slight increase in major bleeding.

Contraindications for new agents are those with prior intracranial bleed, and for Prasugrel, those with history of prior TIA or ischemic stroke.

Not to be given in the ED! Supposed to be given in the cath lab after the cardiologist decides that the patient is a candidate for a PCI and not a CABG.

Avoid using early because the guidelines do not support that!

Same benefit if given right before the PCI in the cath lab when patient is a candidate for the cath lab.

These are high risk patients in the studies, either STD or transient STE.

Everybody starts with ASA. Even if they say they have history of GI bleed or rash.

If a patient has true anaphylaxis to ASA, give clopidogrel/ticagralor.

Also, they should get a 2nd antiplatelet medication, should get clopidogrel/ticagralor. Have to decide is this patient going to get invasive or noninvasive therapy. If patient is getting invasive therapy, give 600 mg of clopidogrel or 180 mg of ticagalor. G2b3a inhibitors falling out of favor, but can give only if going to cath. If not going to cath, give 300 clopidogrel or ticagralor.

These medications do not need to be given in ED, can defer to cardiologist.

Also, give same class rating for unfractionated heparin v low molecular weight heparin v fondaparinux. Can use bivalirudin if patient is going to be treated invasively.

Both agree that unfractionated heparin may be preferable in case the patient needs a CABG.

Re: Invasive v conservative therapy. If you are at a place with no cath lab, usually you would treat and admit. Worth knowing that somebody with following criteria should be transferred to cath facility:

-NSTEMI w/ elevated troponin or new STD
-New heart failure or valvular regurgitation
-ventricular arrhythmias
-Recent PCI/CABG
-Hemodynamic instability
-High TIMI/Grace score

Doses for these meds have not been studied for elderly patients (>70).
Clopidogrel interacts with PPIs, do not use these together, PPIs inhibit the antiplatelet effects. Use H2 blockers if patient has GI issues.

NO GOOD WAYS OF TELLING WHO WILL END UP NEEDING CABG. DO NOT FEEL PRESSURED TO GIVE THESE TO YOUR PATIENTS.

Post-Test Here

 

 

 

 

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Sick Baby: Undifferentiated infant under 3 months

By Eduardo LaCalle, MD

Please refer to EMPEM

According to the podcasters, 10% of neonates with fever will have a serious bacterial infection (SBI), so full workups indicated in all these patients

Important physiologic considerations include changes in circulatory system
-ductal dependent lesions becoming clinically significant after closure of PDAs and PFOs
-will often present after discharge from neonatal ward and many missed on prenatal scans

Things to ask in the history:
-perinatal complications: PROM, fetal distress, NICU admission, hyperbilirubinemia, group B status
-FMH, including prior fetal demise or infant deaths
-how is baby feeding? Tires out, sweats?
-if baby looks well, ask parents what they saw that made them worried

Approach to physical exam: ABCD
-airway: patent, sonorous, stridor?
-breathing: work of breathing. (lung sounds physiologically coarser in this age group)
-circulation: cyanosis, pulses, murmurs, edema and hepatomegaly
-disability (neuro): tone, fontanelle (don’t get caught up on this one unless you think that bulging fontanelle is relevant)
-derm: look for bruising as these patients are at-risk for abuse, look for scrotal discoloration suggesting congenital adrenal hyperplasia (CAH)
-on vitals: remember hypothermia common in sepsis

Ddx:

Airway issues: FB, anaphylaxis (rare)
Breathing: RSV with apnea, traumatic pneumothorax, pna, ALTEs
Circulation: ductal lesions, HF with congenital defects, NSVT (also rare)
Neuro: bleeds (spontaneous vs traumatic), tox
Infectious: bacteremia, viremia, meningitis
Metabolic: in-born errors, poor nutrition, congenital adrenal hyperplasia
GI: intussusception, malrotation, hernias

The work-up. Broad, but podcasters named these specifically:
-fever gets the urine, likely cxr, blood cx, lumbar puncture
-fingerstick early, ammonia level if thinking metabolic
-ekg for cardiac presentations

Post-Test Here

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Intussusception

By Eduardo LaCalle, MD

Please refer to EMPEM

Epidemiology:

Incidence (in UK) 1.6 – 4/1000 children

Seen more commonly in boys, especially with increasing age

Represents about 25% of emergent abdominal surgeries in children < 5 years

 

Pathophys:

Generally caused by a “lead point” in the intestines, but in youngest patients can be idiopathic

After the telescoping of bowel begins, the lymphatics are obstructed first -> bowel edema -> venous obstruction -> arterial obstruction -> necrotic bowel -> shock and death

Shock can develop from third spacing or sepsis.

 

Presentation:

Difficult to diagnose clinically; hard to distinguish from the multitude of AGEs seen

Few will present with classic triad of abdominal pain, vomiting and red-currant jelly stools

Podcasters highlight these telling features that clued them into intussusceptions:

  • Acute onset abdominal pain, colicky with peristalsis
  • Appearing pale and lethargic between episodes of pain (this seems key)
  • Drawing the legs up to the chest
  • In contrast to AGE, will have decreased stool output
  • Palpating a sausage-like mass in the abdomen (infrequent, but obviously suggestive of the dx)

 

Imaging:

Abdominal xrays. The podcasters are not big fans. Cite low sensitivities of 40-60%. Look for absence of bowel gas in right iliac fossa.

Ultrasound. The study of choice. Sensitivity approx 90% with sensitivity of 98%. Look for “target sign” of telescoping bowel on transverse cuts.

Barium enema. The old standard. Risk of bowel perforation, especially in kids > 3 years old. Upside is that it can be therapeutic.

 

Treatment:

Air enema. Done with manometry to reduce risk. You should have surgeon doing it or present. 5-10% incidence of recurrence with this method.

Surgical reduction. Indications included failed reduction by enema and known surgical lesions (ie tumor, FB, etc).

 

Post-Test Here

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Ventilator Management

By Jake Isserman, MD

Please refer to EMRAP

An asthmatic patient had failed NIV and been intubated.  The vent alarm was continuously sounding—for high peak pressure. He was sating 100%.

 

The team had been adjusting the settings and had reduced the tidal volume to 300cc and the respiratory rate to five, but the alarm was still sounding.

 

Why is the high peak pressure alarm especially concerning?

 

Because it is an alarm AND a vent setting.

 

The pressure limit alarm will cause the ventilator to both alarm and STOP DELIVERING a breath—so your patient will not be ventilated as long as the peak pressure alarm is sounding.

 

What pressure is the peak pressure alarm measuring, do we care?

 

Peak Inspiratory Pressure (PIP) which is measuring the resistance in the ET tube, bronchi and bronchioles.

 

Not really, this is not physiologically relevant.

 

What pressure do we care about?

 

Plateau Pressure (PP).  This is what the alveoli see and is concerning for barotrauma and PTX,

 

How do we measure PP?

 

You must press and hold the inspiratory hold button to see the PP. If the value is <30, barotrauma is not a concern.

 

Why was the patient still sating 100%?

 

Oxygenation requires a very small amount of TV, only 200cc/min

 

Vent Alarm Checklist

 

1)    Run to the bedside.

2)    Check for disconnected tubing

3)    Suction for mucus plugging

4)    If >10 seconds, disconnect vent, use BVM (with PEEP valve if pt received peep on ventilator) to manually bag.

5)    If the alarm was for high PIPÞ go to alarm settingsÞ increase pressure limit to 80-100.

Then check PP:

If <30 Þ treat high resistance with suctioning, bronchodilators, and assess for ET tube slippage into R main stem intubation.

If >30Þ the concern is for air trapping, decrease RR and TV to allow for full exhalation.

Post Test Here

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Posterior MI: The Dark Side of the Moon

Goreselen et al.

Neth Heart J. 2007 January; 15(1): 16–21.

By Vincent Roddy, MD

Background: True posterior MI is difficult to recognize bc the leads of the standard EKG are not a direct representation of the area involved.   Only with indirect changes in the precordial leads can help increase suspicion.

One of the most commonly missed types of acute MI.  Clinical presentation is similar but absence of traditional EKG findings such as STE can lead to errors.  Correct interpretation and use of the posterior leads V7-V9 can help establish diagnosis.

ECG shows sinus rhythm with tall R wave in lead V2, minimal ST segment elevation in lead III and ST depressions in leads V2 to V5, I and aVL.  ST segment elevations in posterior leads V7-V9.

The term Posterior MI (PMI) refers to necrosis of the dorsal, infraatrial part of the left ventricle underneath the AV sulcus.

PMI represents 15-21% of acute MI, often accompanied by inferior and/or lateral MI.

Rapid recognition of PMI is important, patients with concomitant inferior or lateral MI have a larger-sized infarct with increased risks of complications.

Patients with PMI often do not receive appropriate reperfusion therapies , likely due to lack of STE.

There is loss of electrical forces in a dorsal direction, STE appear with posterior leads – when electrodes are placed dorsally between the spine and the left scapula.  On standard EKG, PMI leads V1 and V2 are a mirror images of the V1 and V2 leads of anterior MI.

An increase in the R/S radtio > 1.0 occurs in leads V1 and V2 and PMI evolves.

Right precordial horizontal ST segment depression with tall, upright T waves indicates early EKG sign of ischemia of the posterior wall during a progressive PMI.

Mortality reduction is highest when reperfusion of the infracted vessel is done within 6 hours of pain onset, best results during the first hour.

Posterior leads V7-V9 increase detection of posterior injuy.

V7: Placed at the level of lead V6 at the posterior axillary line

V8: Left side of the back at the tip of the scapula

V9: Placed halfway between lead V9 and left paraspinal muscles

STE > 1mm in posterior leads suggests PMI

PMI is responsible for subtle changes on EKG.  For dx we must recognize clinical signs, combined with subtle EGK manifestations to start reperfusion therapy.

ST segment depressions with upright T waves and prominent R waves in leads V1 to V3 should lead to consideration of posterior MI.  Posterior leads can be added to increased EKG sensitivity.

Post-Test Here

Posted in 1Advanced, Cardiology, Chest pain, EKG | Leave a comment

Hyperglycemia

By Christie Lech, MD
Please refer to EMRAP

  • DKA can occur in type I and type II diabetics.
  • A hyperglycemic patient that is not ketotic, not in DKA, is a patient that we DO NOT need to treat for an emergent condition.
  • Giving a hyperglycemic patient fluids will make a difference in how that patient feels.  These patients have a free water deficit.  You can give them some water to drink as well.  There is basically no utility to give these patients insulin.
  • You can start Metformin on patient’s with new diagnosis of diabetes (after you check basic labs including creatinine +/- LFTs) and have them follow up with a primary care physician
  • Patient with heart failure, renal failure, and liver problems are at risk for lactic acidosis if they are taking Metformin
  • Most common side effect of Metformin is GI upset – and it can be severe and happen quickly.  Let the patient’s know this is a common and extinguishable side effect.  One third of patients can have significant GI upset.
  • Recommended starting dose of Metformin is 500 mg BID
  • If patient’s have GI upset, you tell them to half their dose until they have symptom improvement i.e. try Metformin 500 mg qd, and if they still have symptoms, try Metformin 250 mg qd.  Then they can titrate their dose back up
  • American Diabetes Association recommendation for who should be screened for diabetes: adults with a BMI > 25
  • How to diagnose diabetes:
    • HgB A1C of greater than 6.5,
    • fasting glucose of greater than or equal to 126
    • random or non-fasting glucose of greater than or equal to 200 WITH SYMPTOMS
  • Stress responses can cause hyperglycemia, but that does not necessarily mean the patients have diabetes (you classically see this in trauma patients)
  • Endocrinologists surveyed by Aurora say you can tell by how a hyperglycemic patient looks (along with screening for electrolyte abnormalities or renal failure) whether you need to hydrate with IV fluids and get their sugar down
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Cellulitis and MRSA

By Christie Lech, MD
Please refer to EMRAP

  • Cellulitis, without the presence of an abscess, it is a disease usually caused by Strep species.
  • Moran treats cellulitis as MRSA if there is the presence of folliculitis and/or if he is unsure if there is an abscess possibly forming. He recommends giving patients either [ Keflex + Bactrim ] or [ Clindamycin ].
  • Moran prefers Keflex + Bactrim because it is less expensive and has less side effects i.e. GI upset, C. diff
  • Bactrim works well against Staph (MSSA, MRSA) but does not work well against Strep
  • Doxycycline also effective against MRSA
  • Abscesses – Moran still treats most with just drainage.  We don’t know if there is a group of patients that will benefit from antibiotics.
  • There was a study done in children that came up with the ‘5 cm rule’ – if an abscess is greater than 5 cm, there were more treatment failures with just drainage
  • Patients with significant area of cellulitis (more than a few cms around folliculitis/abscess) should get antibiotics.  Also if the patient has systemic symptoms, i.e. fever; also if they are poor protoplasm i.e. diabetic, have poor circulation, if there is tissue damage, etc
  • When Moran gives antibiotics for a cellulitis related to an abscess, he gives a 3-5 day course, because the benefit of antibiotics is marginal.
  • The probability of a patient with an abscess having MRSA is 50% (or greater)
  • Patients with recurrent abscesses – no benefit has been shown with use of prophylaxis or decontamination regimens
  • Mupirocin regimen: use BID x 5 days
  • Mupirocin may select out for bacterial resistance over time, so Moran prefers chlorhexidine
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The Utility of Adding Expiratory or Decubitus Chest Radiographs to the Radiographic Evaluation of Suspected Pediatric Airway Foreign Bodies

Please refer to Annals of Emergency Medicine. Vol. 61. No 1. PP 19-26. Jan 2013.

Brown et al.

By Brandy Ferguson, MD

Study Objective:

To compare standard chest radiographs (lateral or PA or AP) with and without additional views (expiratory or bilateral decubitus) in the evaluation of children with suspected foreign bodies.

 

Methods:

This was a prospective study, which looked at 328 patients with suspected airway foreign bodies from 1997 to 2008. These patients had standard and special view chest radiographs. Out of the 328, 192 had left and right decubitus views, 133 with expiratory views, and 3 with both views.

 

Radiologists were blinded to all clinical information other than patient age. Characteristics from the standard view interpretations were then compared to standard plus special views.

 

Results:

The sensitivity and specificity of the radiographs in detecting foreign bodies were, respectively:

  • Decubitus (standard 2-view)- 56% and 79%
  • Standard + decubitus views- 56% and 64%
  • Expiratory (standard 2-view)- 33% and 70%
  • Standard + expiratory views- 62% and 72%

 

For standard plus decubitus views versus standard alone, the relative sensitivity was 1.0 (0.36/0.21; 95% CI 1.3 to 2.37) and the relative 1-specificity was 1.76 (0.36/0.21; 95% CI 1.3 to 2.37)

 

For standard plus expiratory views versus standard views alone, the relative sensitivity was 1.87 (0.62/0.33; 95% CI 1.23 to 2.83) and the relative 1-specificity was 0.93 (0.28/0.3; 95% CI 0.6 to 1.44)

 

Take-Home Points:

  • The addition of decubitus to standard views increased false positive without increasing true positives and lacks clinical benefit.
  • The addition of expiratory views increases true positives without increasing false positives. However, test accuracy is low and the clinical benefit is uncertain
Posted in 1Beginner, Annals, pediatrics | Leave a comment

Post Cardiac Arrest Syndrome: a review of therapeutic strategies

Stub D, Bernard S, Duffy SJ, Kaye DM.

Circulation. 2011 Apr 5; 123(13):1428-35

 

By Felipe Teran, MD

 

Article capsule

The significant morbidity and mortality associated with patients who survive to an Out-of-Hospital Cardiac Arrest (OHCA) has driven the attention to the syndrome occurring immediately after return of spontaneous circulation (ROSC). The understanding of the physiopathology of this syndrome has allowed the development of problem-based therapeutic interventions. Systems organization, respiratory, circulatory and neuroprotective therapeutic strategies, together with the prompt treatment of underlying coronary disease have been studied extensively. Among all, therapeutic hypothermia (TH) accumulates the strongest and most practice changing evidence improving survival and good neurological outcome in survivors of OHCA.

Take- home messages

  • Development of regional systems of care to provide specialized, multidisciplinary management of the Post Cardiac Arrest Syndrome seems reasonable and could improve outcomes in OHCA patients.
  • Arterial hyperoxia has been found to be an independent factor of increased mortality. Oxygenation and ventilation should be directed to avoid both hypoxia and hyperoxia.
  • Early hemodynamic stabilization should be attempted using fluid therapy and vasoactive drugs as first step.
  • Optimal hemodynamic targets remain unclear but in light of the limited existing evidence, it is reasonable to aim a mean arterial pressure of 65 to 100 mmHg.
  • Mechanical support, such as aortic balloon pump and extracorporeal membrane oxygenation (ECMO) should be considered, particularly in the setting of Acute Coronary Syndrome (ACS) complicated with cardiogenic shock and severe left ventricular dysfunction. However, of these therapies, only ECMO has shown to improve survival.
  • Approximately two thirds of the deaths during the post cardiac arrest period are explained by the anoxic brain injury.  This effect appears to be effectively palliated by the early initiation of therapeutic hypothermia (TH) with a number needed to treat (NNT) of 6.
  • Two major, multicenter, randomized– controlled trials have shown a significant improvement in both survival and good neurological recovery with TH in patients in whom the initial cardiac rhythm is ventricular fibrillation (VF) or Ventricular Tachycardia (VT). It is still unclear whether this effect would apply to asystole and pulseless electric activity (PEA).
  • There are not definitive evidence-based recommendations regarding the method to use and the duration of TH.
  • In light of several observation studies showing the efficacy of early percutaneous coronary intervention (PCI) in patients with STEMI after OHCA, urgent interventional approach for all STEMI with OHCA patients is currently recommended.
  • It is still unclear whether patients with OHCA but no evidence of STEMI should or not have urgent PCI following return to ROSC, but in light of the available evidence, current guidelines suggest that it is reasonable to consider PCI in all survivors of OHCA in whom there is suspicion of cardiac origin.
  • A number of non-randomized, observational trials have shown that the combination of TH and PCI is safe, feasible and could lead to better survival.
  • Absent pupillary and corneal reflexes at day 3 and the absence of somatosensory evoked potentials to test the integrity of central pathways have both shown to be reliable predictors of poor outcomes; however no factors have been found to be sufficiently reliable to conclude that continued care is futile in a patient recovered from OHCA.
Posted in 1Intermediate, Cardiology, Critical Care, Hypothermia, Resuscitation | Leave a comment