Everything you need to know about anti-emetics, mechanism of action, potency and toxicity:

1) 5-HT3 Blockers - Ondansetron, Granistron

- The most potent anti-emetic, only toxicity is really cost

2) Dopamine Blockers - Metoclopramide

- Can titrate to high doses, causes dystonia, akathisia and mild QT prolongation

3) Anticholinergic - Promethazine, meclizine, diphenhydramine

- Cannot titrate, most sedating, urinary retention in elderly, mild QT prolongation

• 325 mg of aspirin should be given within 48 hours of symptom onset in ischemic stroke; while its good form to give it when appropriate while the patient is still in the ED, per recent guidelines, it is not imperative.

• Aspirin should not be given to stroke patients who will receive tPA.

• Prior administration of aspirin is not a contraindication to giving tPA, however.

• If dysphagia and/or aspiration risk is suspected, give 300 mg of aspirin per rectum.

2007 AHA and ASA Guidelines for the Early Management of Adults with Ischemic Stroke and Guidelines for the Management of Spontaneous Intracerebral Hemorrhage in Adults.

ECG gating CTs for aortic dissection/aneurysm rule out

• Increasing evidence supports the use of ECG gating when performing CTs to rule out aortic pathology-dissection and aneurysm.
• The most common artifact on CT is a "psuedo-dissection" flap caused by excessive motion at the aortic root. Administering beta blockers before CT will limit this motion and decrease the chance of this false positive.

AJR 2007

Massive hemoptysis

• Massive hemoptysis is defined by most as the expectoration of > 600 ml in 24 hrs
• Chronic lung inflammatory disease and bronchogenic CA are the most common causes in the US
• TB remains the most common cause worldwide
• The bronchial artery causes approximately 90% of cases
• Get a STAT portable and place the patient in the lateral decubitus position toward the affected side (this is theorectical and has not been proven)
• Options for bleeding control can include endobronchial tamponade methods(pulmonary), bronchial artery embolization (interventional radiology), and emergent surgical resection (surgery)
• Bronchial artery embolization is now the most successful non-surgical treatment of massive hemoptysis

Rheumatic heart disease (RHD) has traditionally been considered the most common underlying condition predisoposing to infective endocarditis. While RHD is still common in developing countries, its prevalence has declined and "mitral valve prolapse is now the most common underlying condition in patients with infective endocarditis."

(from AHA Guideline on Prevention of Infective Endocarditis, Circulation, October 9, 2007)

EMTALA (Part One):

• The three general duties created by EMTALA are to provide (1) an appropriate medical screening examination (MSE), (2) stabilizing care, and (3) appropriate transfer of unstable patients.
• An appropriate MSE is an exam comparable to similarly situated patients (ie: non-discrimatory).
• Patients are stable if it is reasonably likely they will not deteriorate during a transfer.
• The duty to stabilize arises only if the physician diagnoses an emergency medical condition (EMC).
• Once stabilized, the hospital and physician have fulfilled their duties under EMTALA.
• The transfer criteria only apply to unstable patients.
• Receiving hospitals may get fined if they fail to report an inappropriate transfer.
• A hospital with specialized capabilities must accept appropriate transfers if it has the capacity to care for the patient.

Thanks to Larry Weiss, MD, JD

Disclaimer: This information does not constitute legal advice, is general in nature, and because individual circumstances differ it should not be interpreted as legal advice.The speaker provides this information only for Continuing Medical Education purposes.

Pierre Robin Syndrome

• The prime features of this condition are a small jaw (micrognathia), cleft palate, and posteriorly positioned tongue.
• In the newborn period, respiratory compromise from obstruction is of greatest concern.
  • Because the tongue is positioned in the back of the mouth, it tends to block the airway and cause respiratory distress.
  • In severe cases, a tracheostomy may be required to provide a stable airway for the patient. (We just had an emergent tracheostomy done in our NICU this month).
• Severity of airway obstruction varies from mild to life-threatening.
  • With only mild distress, attempt to relieve the obstruction by placing the child on his or her stomach; gravity will help to keep the tongue out of the airway.
  • Resuscitation of babies with more severe obstruction may be difficult because the micrognathia and the posteriorly protruded tongue can contribute to inadequate face-mask ventilation and make endotracheal intubation difficult (or impossible).
  • Consider LMA as a bridge to tracheostomy.
  • As soon as you recognize the presence of mirognathia, have someone call pediatric anesthesia and pediatric surgery.

Baraka, A. Laryngeal Mask Airway for Resuscitation of a Newborn with Pierre-Robin Syndrome. Anesthesiology. 83(3):646-647, September 1995.

• Risk Factors for RCIN: Renal insufficiency, >60 yr old, DM, Renal Transplant, Hypovolemia, EF <30%, concomitant nephrotoxic drugs
• Consider Prophylaxis with anyone of three methods (no method has been found superior.
  • Normal Saline: 1 ml/kg/h IV pre and post study
  • NaHCO3: 3 ml/kg IV bolus over 1 hr then 1 ml/kg/h pre and post
  • IV Acetylcysteine 150 mg/kg bolus over 1hr then 50 mg/kg over 4h

Today's joint conference with the UMMS' Neurology Department was quite beneficial and applicable to our daily practice in the Emergency Department (ED).

The topics discussed included:

• Third Nerve Palsy (aneurysmal versus vasculopathic)
• Painful Post-ganglionic Horner's Syndrome
• Cluster Headache
• Carotid Dissection
• Pituitary Apolplexy

While the information provided for each of these clinical topics was comprehensive, be sure to review these disorders in the near future, in order to commit them to memory and increase your comfort level with diagnosing and treating them in the ED.  If you'd like a copy of the handouts, just let me know.

Today's pearl will highlight pituitary apoplexy.

Take Home Points about Pituitary Apoplexy:

• Defined as hemorrhage or infarction of a pituitary tumor.
• Neurologic emergency that can be fatal, usually due to hemorrhage.
• Typically presents with acute onset of headache +/- meningeal irritation, altered mental status,  photophobia, and  ophthalmoplegia (usually 3rd cranial nerve palsy, followed by 6th and 4th cranial nerve dyfunction).
• CT head (dry) may appear normal.  MRI typically makes the diagnosis.
• Ophthalmoplegia (of 3rd CN) + CSF with significant red cells may prompt an angiogram in search of a PCOM (posterior communicating artery) aneurysm, when an MRI is acutally all that's needed.
• Treatment:  high dose steroids (hydrocortisone 100 mg IV q 6-8 h) +/- decompressive surgery via Neurosurgery.

Acute Liver Failure

• Acute liver failure (ALF) is defined as the onset of encephalopathy and coagulopathy within 26 weeks of jaundice in a patient without prior history of liver disease
• ALF has an extremely high mortality
• The most common cause of ALF include Tylenol, HSV, autoimmune hepatitis, HBV, and acute fatty liver of pregnancy/HELLP
• Complications EPs are likely to see/manage include hepatic encephalopathy, infection, circulatory dysfunction, bleeding, and seizures
• Fungal infections may be present in one-third of patients with ALF (Candida)
• Non-convulsive seizure activity occurs in a high proportion of patients with ALF and encephalopathy - consider EEG for severly encephalopathic patients and those with a sudden deterioration in neuro status

Stravitz RT, et al. Intensive care of patients with acute liver failure. Crit Care Med 2007;35:2498-2508.

A few pearls regarding Acute Aortic Dissection...

• CXR has been shown to have an overall sensitivity of only 67%!
• Recent literature and a large, recently published, authoratative book by one of the world's leading authorities on aortic dissection support the notion that a negative highly sensitive d-dimer rules out aortic dissection.
• CT scan is the test of choice, but be aware that many authorities are starting to recommend beta blockade before CT to reduce the most common artifact, motion at the aortic root that simulates a dissection flap
• MRI and TTE are reasonable alternatives if a CT can not be ontained
• The most common theme found in malpractice claims against emergency physicians is failure to address the combination of chest/back, back/abdominal pain.

Elefteriades. Acute Aortic Disorders. 2007

Abdominal pain can be very confusing. Occasionally, serious etiologies may masquarade as benign complaints. Always consider the following pitfalls when addressing abdominal complaints.

• Be aware of extra-abdominal disease processes presenting as abdominal pain
  • AMI, pneumonia, pelvic diesases
• If you suspect appendicitis - than pursue the diagnosis
  • Do not delay notification of surgeon, and request consultation early
    • It is reasonable for them to examine the patient without CT results
    • It is not reasonable to withhold pain medications until they see the patient
  • Time all calls, and document all discussions with consultant name
• UTI and gastroenteritis should be considered diagnoses of exclusion. Be wary of using, if any red flags exist
  
  • fever, hypotension, blood in stool, weight loss, abdominal tenderness
• Unless the diagnosis/etiology is clearly not pelvic in origin, always do a pelvic exam in a women
• Always consider, and document your consideration of testicular and ovarian torsion
• In a septic patient with UTI, consider obstructing pyelonephritis.
  • Patients with a kidney stone and obstructing pyelo will not get better unless the stone is removed. CT for stones, prior to dispo.
• Consider vascular etiologies in high risk populations: elderly, diabetic, hypertensive
  • AAA - pain to back, tearing sensation
  • Dissection - pain, decreased pulses, neuro findings
  • Mesenteric Ischemia / schemic Colitis - pain out of proportion to exam findings
  • Torsion - radiating pain to abdomen - document a genital exam

Disclaimer: This information does not constitute legal advice, is general in nature, and because individual circumstances differ it should not be interpreted as legal advice. The speaker provides this information only for Continuing Medical Education purposes.

Content abstracted from: Nguyen Anh, Nguyen Dung. Learning from Medical Errors. Radcliffe Publishing, UK. 2005. P 11-13.

The standard dose for adenosine in treating SVT is 6 mg given as a rapid IV push. The dose should be immediately followed by a saline flush and works best if the drug is administered through a good, proximal (e.g. antecubital) IV line.

A few points:

1. The initial dose of adenosine should be reduced to 3 mg if the dose is administered through a central line, if the patient has a transplanted heart, or if the patient is taking carbamazepine or dipyridimole.
2. The initial dose of adenosine should be increased to 9-12 mg if the patient is taking theophylline or large doses of caffeine.
3. ALWAYS warn the patient that he/she will experience 5-10 seconds of chest pressure, warmth, dyspnea, and perhaps a feeling of "impending doom" as the adenosine kicks-in, and reassure the patient that the sensation will resolve. Failure to warn the patient of these symptoms may result in the patient refusing to ever take the medication again...plus it's just plain cruel to not warn the patient.

Proteinuria

• Proteinuria on U/A may suggest underlying renal disease; however, it may be present for benign reasons as well:
  • A very concentrated urine (SG ≥ 1.020)
  • Alkaline urine (pH ≥ 7.5)
  • Presence of mucoproteins
  • Acute illness

• Benign processes almost never produce proteinuria above 1+.
• If proteinuria is detected in the ED in an asymptomatic patient:
  • Have the patient f/u with PMD for repeat u/a within 1-2 weeks
  • Recommend checking a first morning urine sample and urine protein: creatinine ratio (to rule out orthostatic/transient proteinuria).

• If proteinuria persists or is evident on first morning urine sample, then a renal biopsy may be indicated.
• Chemistry panels, CBC’s, renal ultrasound, and 24-hour urine collection rarely change the plan.
   

Chandar J, Gomez-Martin O, del Pozo R, et al. Role of routine urinalysis in asymptomatic pediatric patients.  Clin Pediatr (Phila). 2005; 44:44-48.

Hogg RJ, Portman Rj, Milliner D, Lemley KV, Eddy A, Ingelfinger J. Evaluation and management of proteinuria and nephritic syndrome in children recommendations from a pediatric nephrology panel established at the National Kidney Foundation Conference on Proteinuria, Albuminuria, Risk, Assessment, Detection, and Elimination (PARADE). Pediatrics. 2000; 105: 1242-1249.

A short list of some of the unique food poisonings and the toxicologic effects:

• Ciguatera toxin (fish): hot-cold sensation reversal
• Tetrodotoxin (fugu, puffer fish): paresthesias progressing to paralysis and dysrythmias
• Scrombroid (spoiled fish): flushed face due to histamine ingestion
• Paralytic Shellfish Poisoning (mussels, clams, etc): acts like curare, toxin is saxitoxin
• Amnestic shellfish poisoning (mussels): exactly what it says, loss of memory - very cool

A few days ago Dr. Jump and I had a case of an acute variceal hemorrhage.  Dr. Bond already sent out a great pearl earlier in the year highlighting the importance of octreotide in acute variceal bleeding.  In fact, octreotide alone can result in cessation of hemorrhage in up to 80% of patients.  To add onto Dr. Bond's pearl:

• Don't forget about antibiotics in acute variceal hemorrhage
• These patients have a relatively high incidence of bacteremia, which leads to worse outcomes
• Antibiotics have been shown to decrease infection rates and are associated with decreased rebleeding and the need for transfusions
• A 3rd generation cephalosporin is currently the recommended antibiotic of choice

Patients with aortic dissection (Type A or B) who develop intestinal/renal, etc. ischemia should be considered for aortic fenestration-a procedure in which holes are literally created in the aortic lumen to connect the true and false lumen-this allows perfusion of the involved vessel to occur from true lumen into the false lumen into the involved vessel.

Patients with large vessel malperfusion have a VERY HIGH mortality rate, AND most CT surgeons will not operate even on a Type A unless the involved vessels have been opened up.

This procedure is useful when major vessels (SMA as an example) branch from the aortic false lumen.

So, when to consider this procedure:

• Aortic Dissection (A or B) with severe abdominal pain, elevated lactate, OR imaging study showing malperfusion to a vessel (SMA, renal, etc)
• Most of the time in the ED we will see this on CT in a sick patient.

Who do you call?

• Vascular Surgery and IR-normally perormed percutaneously via a femoral approach

A few pearls regarding pacing a patient with an unstable bradycardia:

If the patient has an implanted pacemaker (which isn't working properly), the transcutaneous pacing pads should be placed at least 10 cm away from the implanted PM pulse generator.

Placement of a transvenous pacemaker is absolutely contraindicated if the patient has a prosthetic tricuspid valve.

Neither transcutaneous or transvenos pacing is likely to work in the setting of severe acidosis or severe hypothermia. Severely hypothermic patients, in fact, have very irritible myocardial tissue and therefore attempts at pacing may produce ventricular dysrhythmias.

Volvulus Quick Facts

• Volvulus causes 10-15% of large bowel obstructions and occurs most commonly in the elderly.
• The most common type of volvulus is sigmoid volvulus.
• Midgut volvulus is most common in the neonatal period.
• Cecal volvulus:
  • Occurs in all ages, but most commonly in the 25- to 35-year-old age group
  • Associated with:
    • previous abdominal surgeries
    • young, healthy marathon runners.
• Sigmoid volvulus most commonly occurs in two groups of individuals:
  • Inactive elderly persons with a history of severe chronic constipation
  • Patients with severe psychiatric or neurologic disease.

Atrial Myxomas:

• Rare primary heart tumor
• Most involve the left side of the heart

• Symptoms may include fatigue, fever, rash, chest pain, syncope, and/or focal neuro deficits
  • Symptomatic emboli occur in 20-45% of pts with atrial myxomas
  • >50% of emboli go to the brain
  • Hemiplegia, aphasia, retinal artery occlusion, embolic “rash” in a child should all raise concern for cardiac source in pediatric pt.
    
    • Embolus from the heart is the most common cause of retinal artery occlusion in pts <40yrs.

• Emboli are most often myxoma tissue and not blood clot (so thrombolytics aren’t of much value)

Majeed Al-Mateen, et al. Cerebral Embolism From Atrial Myxoma in Pediatric Patients. Pediatrics, Aug 2003; 112: e162 - e167.