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Title: New TWI in aVL

Category: Cardiology

Keywords: ECG, STEMI, aVL (PubMed Search)

Posted: 2/9/2014 by Ali Farzad, MD (Updated: 3/23/2014)

The importance of new ST-segment depressions (STD) and/or T wave inversions (TWI) in lead aVL have not been emphasized or well recognized across specialties. Computer-assisted ECG readings typically report these findings as normal or nonspecific. 

There is growing evidence that changes in lead aVL are abnormal, and that paying attention to that lead can be clinically useful. Reciprocal changes presenting as STD or TWI in lead aVL may be indicative of a significant coronary artery lesion and can sometimes be the only ECG manifestation of acute MI.  

STD in lead aVL is considered a sensitive marker for early inferior STEMI, and has been shown to help differentiate STEMI from pericarditis. Another recent retrospective study suggests that TWI in aVL might be associated with significant LAD lesions. 

Bottom Line: Paying close attention to subtle changes and abnormalities in lead aVL may help in early identification and initiation of therapy for patients who are having an acute MI.  

Show References

Hassen GW, Costea A, Smith T, et al. The Neglected Lead on Electrocardiogram: T Wave Inversion in Lead aVL, Nonspecific Finding or a Sign for Left Anterior Descending Artery Lesion?. Journal of Emergency Medicine. 2014;46(2):165–170.

Want more emergency cardiology pearls?
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Attachments

  • 1402092205_TWI_in_aVL.pdf (112 Kb)


Title: Overtraining Syndrome

Category: Orthopedics

Keywords: Overtraining syndrome, exercise (PubMed Search)

Posted: 2/8/2014 by Brian Corwell, MD

Overtraining syndrome

A maladaptive response to excessive exercise without adequate functional rest

-Results in disturbances of multiple body systems (neurologic, endocrinologic, immunologic and psychologic).

- May be caused by systemic inflammation and resultant neurohormonal changes
            - Multiple hypotheses exist

-Symptoms

Parasympathetic alterations: fatigue, depression, bradycardia

Sympathetic alterations: insomnia, irritability, agitation, tachycardia, hypertension, restlessness

Other: anorexia, weight loss, poor concentration, anxiety

 

Usual presentation is prolonged underperformance despite adequate rest and recovery (weeks to months).



Title: Goal-Directed Therapy for Children With Suspected Sepsis

Category: Pediatrics

Posted: 2/7/2014 by Rose Chasm, MD (Updated: 7/22/2026)

  • Much attention has been paid towards early goal-directed therapy for sepsis in adult ED patients, but there has not been as much consideration for the pediatric ED patient. 
  • R-C analyses and M&M reviews have consistently identified system difficulties  recognizing sepsis in children, especially cases of compensated shock, and subsequent management.
  • Protocols beginning in triage to recognize abnormal vital signs, followed by timely execution of interventions especially antibiotic and fluid administration are worthwhile to reduce overall morbidity and mortality.
  • Protocols should include 3 major goals:
  1. Triage vital signs adjusted for age, and corrected heart rate for pyrexia to recognize sepsis.
  2. Obtain vascular access within 5 minutes followed by a 20mL/kg bolus of IV fluids administered within 15 minutes in cases of volume depletion.
  3. Antibiotic administration within 30 minutes.

Show References

Cruz AT, Perry AM, Williams EA, et al. Implementaion of Goal-Directed Therapy for Children With Suspected Sepsis in the Emergency Department. Pediatrics 2011;127;e758.



Title: Ondansetron Induced Dystonia

Category: Toxicology

Keywords: ondansetron, dystonia (PubMed Search)

Posted: 2/6/2014 by Fermin Barrueto (Updated: 7/22/2026)

Ondansetron (Zofran) is a great anti-emetic that, since it has gone generic, is also inexpensive. High dose ondansetron has been reported to cause QT prolongation and that practice is largerly discontinued now in the oncology world. Another uncommon adverse drug reaction may be dystonia. Though we think of ondansetron as a 5-HT3 blocker and should not cause the dystonic reaction like we see in metoclopramide, there are case reports of this reaction occurring.

 

 

 

 

 

Ondansetron-induced dystonia, hypoglycemia, and seizures in a child.
Patel A, Mittal S, Manchanda S, Puliyel JM.
Ann Pharmacother. 2011 Jan;45(1):e7.
 
 


Title: Tranexamic Acid in Anterior Epistaxis

Category: Pharmacology & Therapeutics

Keywords: anterior epistaxis, tranexamic acid, antifibrinolytic (PubMed Search)

Posted: 2/6/2014 by Ellen Lemkin, MD, PharmD

Tranexamic Acid (TXA) topically applied was compared to anterior nasal packing in 216 patients with acute anterior epistaxis. Cotton pledgets (15 cm) soaked in injectable TXA (500 mg/5 ml) were inserted into the bleeding nostril and removed after bleeding had arrested. This was compared to standard anterior packing.

RESULTS

                                                                   TXA            Anterior packing

% pts bleeding stopped in 10 min:           71%           31.2%                

Discharge after 2 hours                           95.3%           6.4%

Rebleeding in 24 h hours                          4.7%        11%

Satisfaction scores                                    8.5               4.4

 

Bottom line: topical tranexamic acid looks promising for control of uncomplicated anterior epistaxis.

Show References

Zahed R, Moharamzadeh P, AlizadeArasi S, Ghasemi A, Saeedi M. A new and rapid method for epistaxis treatment using injectable form of tranexamic acid topically: a randomized controlled trial. AJEM 2013 (31):1389-92.



Title: Vulnerable Road Users

Category: International EM

Keywords: road traffic accidents, international, global, public health (PubMed Search)

Posted: 2/5/2014 by Andrea Tenner, MD (Updated: 7/22/2026)

General Information:

  • 1.24 million people die each year on the world's roads
  • 50% of those dying on the world’s roads are vulnerable road users (VRUs-- those most at risk in traffic, i.e. those unprotected by an outside shield)
    • 23% motorcyclists, 22% pedestrians, 5% cyclists
    • Children and elderly are overrepresented among victims

Area of the world affected:

  • In 2010, low- and middle-income countries had higher road traffic fatality rates (18.3 and 20.1 per 100,000, respectively) compared to high-income countries (8.7).
  • The African region had the highest road traffic fatality rate, at 24.1, while the European region had the lowest rate, at 10.3.

Relevance to the US physician:

  • While public health measures are key in reducing the risk to VRUs, improving the provision of emergency medical services may also result in a higher proportion of victims surviving on the road or on the way to a health clinic.
  • Travelers should also be mindful of the risks of motorcycles, bicycles, and walking along the roadside

Bottom Line:

VRU traffic injuries are the greatest challenge of today's worldwide road safety. 

University of Maryland Section of Global Emergency Health

Author: Terrence Mulligan DO, MPH

Show References

http://www.who.int/gho/road_safety/en/

http://www.plosmedicine.org/article/info%3Adoi%2F10.1371%2Fjournal.pmed.1000228

http://www.grsproadsafety.org/our-knowledge/safer-road-users/vulnerable-road-users



Title: Mechanical Ventilation During ECMO

Category: Critical Care

Keywords: VV-ECMO, mechanical ventilation, ultra-lung protective ventilation (PubMed Search)

Posted: 2/4/2014 by Mike Winters, MBA, MD

Mechanical Ventilation During ECMO

  • ECMO is a rapidly emerging therapy for critically ill patients with severe acute respiratory failure (VV-ECMO) and circulatory failure (VA-ECMO).
  • Mechanical ventilation (MV) settings may have important effects on patients receiving either VV- or VA-ECMO.
  • Though no large, randomized trials, consensus guidelines and expert opinion recommend the following initial settings for patients receiving VV-ECMO:
    • Tidal volume: < 4 ml/kg predicted body weight
    • Plateau pressure: < 25 cmH2O
    • PEEP: 10-15 cmH2O
    • FiO2: titrated to maintain sats > 85%
    • RR: 4 to 6 breaths per minute

Show References

Schmidt M, et al. Mechanical ventilation during extracorporeal membrane oxygenation. Crit Care 2014;18:203.



Title: What's the Diagnosis? Images by Dr. Jennifer Guyther

Category: Visual Diagnosis

Posted: 2/3/2014 by Haney Mallemat, MD

Question

34 year-old left-hand dominant male sustained injury to left hand after his pressurized greasing-gun discharged into the palm of his hand. He has a small lac to the hand but is in extreme pain. On exam his hand is very puffy and he is neurovascularly intact (XR below) What is the next step in management? 

 

Show Answer

Metacarpal fracture; emergent surgical consult is required

High-Pressure Injection Injuries (HPI) injuries

HPI devices (e.g., grease, paint guns, etc.) may cause injury when the device accidently discharges, typically into the operator’s dominant hand during attempts to clean the nozzle.

Injuries may initially appear benign, however injuries should be considered surgical emergencies because they often require debridement / washout of materials injected into deeper tissues.

Tissue damage is multi-factorial and includes direct injury (e.g., high-pressure tissue damage, vascular compression, etc.) and indirect injury from material injected into tissues (e.g., chemical inflammation / injury, granuloma formation, deep-tissue infections, etc.).

Radiographs may assist surgical planning by identifying subcutaneous air, debris, or unanticipated fractures.

Treatment:

  • High-potential for disability and amputation so prompt aggressive therapy and surgical consult is crucial.
  • Broad-spectrum prophylactic antibiotics and update tetanus
  • Splint the extremity and keep it elevated while awaiting disposition

Show References

Follow me on Twitter (@criticalcarenow) or Google+ (+criticalcarenow)



Title: Myocardial Infarction in Women After Childbirth

Category: Cardiology

Posted: 2/2/2014 by Semhar Tewelde, MD

Myocardial Infarction in Women After Childbirth

World Health Organization reports that obesity is the 5th leading cause of global death with the highest impact on women <65 years of age

The association of obesity and cardiovascular risk in young women is currently being researched

A recent nationwide cohort looking at obesity and future cardiovascular risk looked at Danish women giving birth (2004-2009) and followed them a median time of 4.5 years

This study grouped women via pre-pregnancy body mass index (BMI)

                                            1. Underweight (BMI <18.5)     

                                            2. Normal weight (BMI <25)

                                3. Overweight (BMI <30)

                                4. Obese (BMI >30)

Data revealed that healthy women of fertile age, pre-pregnancy obesity alone was associated with increased risk of myocardial infarction in the years after childbirth

Show References

Schmiegelow M, Andersson C, Kober L, et al. Prepregnancy Obesity and Associations With Stroke and Myocardial Infarction in Women in the Years After Childbirth. Circulation 2014;129:330-337. 



Title: Minimum Methadone Dose to Prevent Withdrawal

Category: Pharmacology & Therapeutics

Keywords: methadone, withdrawal (PubMed Search)

Posted: 2/1/2014 by Bryan Hayes, PharmD (Updated: 2/1/2014)

In most situations (dependant on state laws and institutional policies), methadone-maintained patients enrolled in a drug abuse program are best managed by continuing methadone at the usual maintenance levels with once-a-day oral administration.

Pearl: In the event the methadone clinic is closed and/or the dose cannot be verified, 30-40 mg (10-20 mg IM) is generally enough to prevent withdrawal in most patients.

This is only a short-term measure and some patients may require additional methadone. Full doses of methadone should be reinstituted as soon as possible.

Show References

Fultz JM, et al. Guidelines for the management of hospitalized narcotic addicts. Ann Intern Med 1975;82(6):815-8. [PMID 1138596]

Alford DP, et al. Acute pain management for patients receiving maintenance methadone or buprenorpine therapy. Ann Intern Med 2006;144(2):127-34. [PMID 16418412]

Freedman DX, et al. Methadone treatment of heroin addiction. Annu Rev Med 1973;24:153-64. [PMID 4575849]

Follow me on Twitter (@PharmERToxGuy) or Google Plus (+bryanhayes13)



Title: Resistant Etoh Withdrawal - Try Dexmedetomidine (Precedex)

Category: Toxicology

Keywords: dexmedetomidine, alcohol withdrawal (PubMed Search)

Posted: 1/30/2014 by Fermin Barrueto (Updated: 7/22/2026)

 

If you are treating an alcohol withdrawal patient and benzodiazepines are not working, try dexmedetomidine (precedex). This centrally acting alpha-2 agonist was utilized in 18 ICU patients and was shown to be safe. Average diazepam dose was 193 mg IV and lorazepam dose was 9 mg IV in these patients. Haloperidol was utilized in 3 of these patients which is not an effective therapy for alcohol withdrawal (could worsen due to QT prolongation, decrease seizure threshold and anticholinergic effects).
 
Still requires further research and not sure about the physiologic mechanism dexmedetomidine would actually treat alcohol withdrawal aside from sedating. There is the added benefit of maintaining airway reflexes versus propofol. This case series shows the experience with this drug regimen.
 
 
 
 
1. Tolonen J et al. Dexmedetomidine in addition to benzodiazepine-based
sedation in patients with alcohol withdrawal delirium. Eur J Emerg
Med. 2013. 20:425-427.


Title: Tropical Medicine in Your Backyard

Category: International EM

Keywords: Virus, Fever, West Nile, Dengue (PubMed Search)

Posted: 1/29/2014 by Andrea Tenner, MD

Case Presentation: A 63 year old woman from Texas with no recent international travel presents to the ED with persistent fatigue which onset a month ago and is associated with anorexia and occasional fevers and chills.  She has been to her family doctor who tested her for a number of viral illnesses and was told she had West Nile virus.

Clinical Question:

What other febrile illness could this be?

Answer:

This patient had dengue.  Dengue is now endemic in the US, and locally-acquired cases have been reported in Florida, Texas and Hawaii. The fatigue and anorexia are typical and can last for weeks after other symptoms have resolved. 

West Nile virus testing may be falsely positive when another flavivirus is present such dengue, yellow fever or Japanese encephalitis. 

Bottom Line:

Other possible illnesses like dengue should be considered in patients who have tested positive for West Nile virus.

 

University of Maryland Section of Global Emergency Health

Author: Jenny Reifel Saltzberg, MD, MPH

Show References

Sharp TM, et al. Fatal hemophagocytic lymphohistiocytosis associated with locally acquired dengue virus infection - New Mexico and Texas, 2012. MMWR Morb Mortal Wkly Rep. 2014 Jan 24;63(3):49-54. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6303a1.htm?s_cid=mm6303a1_w

Centers for Disease Control and Prevention.  Dengue and Dengue Hemorrhagic Fever: Information for Health Care Practitioners. http://www.cdc.gov/dengue/resources/Dengue&DHF%20Information%20for%20Health%20Care%20Practitioners_2009.pdf



Title: Necrotizing Skin and Soft Tissue Infections (NSSTIs)

Category: Critical Care

Posted: 1/28/2014 by Haney Mallemat, MD

NSSTIs occur secondary to toxin-secreting bacteria; NSSTIs are surgical emergencies with a high-morbidity / mortality

Risk factors: immunocompromised host (DM, AIDS, etc.), intravenous drug use, malnourishment, peripheral vascular disease

Type I (polymicrobial; most common), Type II (monomicrobial; typically clostridia, streptococci, staph, or bacteroides), Type III (Vibrio vulnificus; seawater exposure)

Signs / Symptoms: pain out of proportion to exam (occasionally no pain at all), skin findings (blistering / bullae, gray-skin discoloration, or “Dishwater-like” discharge), or systemic toxicity (altered mental status, elevated lactate, etc.)

Diagnostic radiology

  • Xray (shows gas); low sensitivity; CT scan (gas / tissue stranding); sensitivity is also low
  • MRI can over-diagnose NSSTI and should not be used routinely
  • Bedside ultrasound may demonstrate fluid or gas collections in deeper tissues (see clip below)

Treatment is emergent surgical debridement with simultaneous hemodynamic resuscitation PLUS broad-spectrum antibiotics; consider clindamycin becuase it has anti-toxin activity

Adjunctive therapies include Intravenous intraglobulin (neutralizes toxins secreted by bacteria) and hyperbaric oxygen

Show References

Follow me on Twitter (@criticalcarenow) or Google+ (+criticalcarenow)



Title: What's the Diagnosis?

Category: Visual Diagnosis

Posted: 1/27/2014 by Haney Mallemat, MD

Question

32 year-old with diabetes presents with fever, erythema, and warmth of his lower extremity; his leg is not particularly painful. He is diagnosed with cellulitis, started on antibiotics, and admitted to the hospital. While boarding in the Emergency Department he becomes rigorous and hypotensive. An ultrasound of his cellulitis is performed and is shown below. What’s the diagnosis?

 

Show Answer

"Cobblestoning" of subcutaneous tissue consistent with cellulitis. There are also areas of subcutaneous air raising the concern for necrotizing fasciitis.

Special thanks to Dr. Mike Mallin from the Ultrasound Podcast for the clip. Want to see more amazing ultrasound clips? Check out Sonocloud

Show References

Follow me on Twitter (@criticalcarenow) or Google+ (+criticalcarenow)



Title: Extremely Fast & Wide Complex Regular Tachycardia

Category: Cardiology

Keywords: Wide complex tachycardia, ventricular tachycardia (PubMed Search)

Posted: 1/26/2014 by Ali Farzad, MD (Updated: 3/23/2014)

Question

A 48 year old woman has acute chest pain and palpitations over the past several hours. She has felt similar palpitations in the past but never sought medical attention. She arrives to your ED alert and anxious. HR = 270, BP=130/100. ECG is below. What’s the diagnosis and treatment?

Show Answer

Most wide complex regular tachycardias are ventricular tachycardia (VT). However, supraventricular tachycardias can also cause wide complexes through aberrant conduction and accessory pathways.

The exact diagnosis of a tachydysrhythmia is often irrelevant in the ED management of unstable patients. Clinical stability is a more important determinant of treatment than the underlying rhythm. This patient was thought to have VT and was successfully cardioverted. 
 
Subsequent EP study confirmed Atrial Flutter with 1:1 conduction and Wolff-Parkinson-White (WPW) Syndrome.
 
Why is this important?
 
Accessory pathways can be concealed, and lack of delta waves do not rule out preexcitation syndromes such as WPW. 
 
Consider this diagnosis in patients with the triad of extremely rapid rate (>250 bpm), regular rhythm, and wide QRS complexes. 
 
This is particularly important if pharmacological treatment is chosen rather than cardioversion. Any treatment that slows AV nodal conduction may cause preferential conduction down the accessory pathway and precipitate cardiovascular collapse. 
 
Bottom-line: 
 
When treating extremely fast wide complex rhythms, avoid the ABCD Meds (Adenosine, Beta-Blockers, Ca2+ Channel Blockers, & Digoxin). Instead, consider using Procainamide or cardioversion!

Show References

Nelson JG, Zhu DW. Atrial Flutter with 1:1 Conduction in Undiagnosed Wolff-Parkinson-White Syndrome. The Journal of Emergency Medicine. January 2014. Pubmed Link

Want more emergency cardiology pearls?
Follow me on Twitter @alifarzadmd

Attachments

  • 1401260828_JEM.WCT.Jan14.pdf (1,636 Kb)


Title: Pellegrini Stieda lesion

Category: Orthopedics

Keywords: MCL, knee, (PubMed Search)

Posted: 1/25/2014 by Brian Corwell, MD (Updated: 1/25/2014)

Pelllegrini-Stieda lesion

Ossified post-traumatic lesions at the MCL adjacent to the femoral attachment site of the medial femoral condyle.

Mechanism is likely from an avulsion injury that subsequently calcifies after the initial trauma.

Often an incidental finding on plain films.

If symptomatic, refer to ortho as an outpatient

If not symptomatic, no treatment is indicated

 

http://images.radiopaedia.org/images/30076/b62e61e83241e30f2da693901edcdc_gallery.jpg

http://www.imageinterpretation.co.uk/images/knee/PELLEGRINI%20STIEDA2.jpg



Title: Bioaccumulation and the "Therapeutic" Overdose

Category: Toxicology

Keywords: pharmacology (PubMed Search)

Posted: 1/23/2014 by Fermin Barrueto (Updated: 7/22/2026)

Everyone has admitted an altered mental status, patient or bradycardic patient and all of your test results are coming back normal except for a mild increase in creatinine. Take a look at the medication list. Creatinine is a poor indicator of renal function and GFR may be severely impaired even with a mild elevation of creatinine. If you have a predominantly renally excreted drug, you can see toxic effects of a drug even if administered at therapeutic levels.

Common bradycardia inducing medication that is renally cleared: atenolol (very high renal excretion) and digoxin (70%).

Altered Mental Status and on Keppra? Keppra is 100% renally cleared!

Ask your pharmacist for help with the medication list with renal or hepatic insufficiency.



Title: Know your Slytherins

Category: International EM

Keywords: International, snake, venom, (PubMed Search)

Posted: 1/22/2014 by Andrea Tenner, MD

98% of venomous snake bites in the US are due to pit vipers.  Occasionally a snake bite is from an exotic venomous snake being kept as a pet.  In 2005, 142 exotic poisonous snakes were reported to poison control.  It can be very challenging to find antivenom for these exotic animals.

Antivenom is usually specific to a family or subfamily, so the snake must be identified.  Most exotic snake owners will know the common name and possibly the scientific name of the animal.

The WHO database of venomous snakes can help with identification of the species and will list antivenom available globally.

Poison centers are essential to help locate the antivenom and assist with treatment.

Relevance to the EM Physician:

When a patient presents with an exotic snake envenomation, the WHO website below can be helpful to identify the species and possible antivenom.  

http://apps.who.int/bloodproducts/snakeantivenoms/database/

 

University of Maryland Section of Global Emergency Health

Author: Jenny Reifel Saltzberg

Show References

C Lubich and EP Krenzelok. Exotic snakes are not always found in exotic places: how poison centres can assist emergency departments.” Emerg Med J. 2007 November; 24(11): 796–797.

Melisa W. Lai, et al. 2005 Annual Report of the American Association of Poison Control Centers’ National Poisoning and Exposure Database. Clinical Toxicology, 44:803–932, 2006

http://www.who.int/neglected_diseases/diseases/snakebites/en/index.html



Title: A-lines: A Significant Source of Preventable Blood Stream Infections

Category: Critical Care

Keywords: arterial line, catheter related blood stream infections (PubMed Search)

Posted: 1/21/2014 by John Greenwood, MD (Updated: 1/21/2014)

 

Arterial Catheter-Related Blood Stream Infections

Whether arterial lines are a potential source of catheter-related blood stream infections (CRBSIs) is highly-debated; however, based on a recent systematic review they are an under recognized and significant source of CRBSIs.

  • Incidence: In systematically cultured arterial catheters, the infection rate was 1.6 infections/1,000 catheter days which is similar to what has been reported for infections associated with short-term CVC's.
     
  • Location: Femoral a-lines are more likely than radial a-lines to be a source of a CRBSI. Femoral a-line CRBSIs occurred in 1.5% of all catheters (95% CI, 0.8–2.2%), which is higher than radial CRBSI, with a relative risk of infection 1.94 times greater than those placed at the radial site.
     
  • Technique: Only one study specifically evaluated the impact of full barrier precautions versus using sterile gloves only for peripheral a-lines, and it did not find any significant difference in BSI. No study has evaluated the impact of maximal barrier precautions for femoral, axillary, and brachial arterial catheters.
     
  • Dressing: The risk of infection was significantly decreased with the use of chlorhexidine-impregnated dressings (ex: BioPatch).

 

Bottom Line(s) 

  1. Arterial lines appear to be a significantly under recognized source of CRBSI's in critically-ill patients.  If you are deciding to place an a-line for invasive blood pressure monitoring, strongly consider the radial site and use a chlorhexidine sponge or dressing to try and minimize the risk of future BSI.
     
  2. There is a paucity of data regarding the utility of maximal barrier techniques when inserting peripheral arterial lines.  With arterial catheter infection rates approaching that of central venous catheters, we should probably be inserting a-lines with the same sterile technique.

Show References

O'horo JC, Maki DG, Krupp AE, Safdar N. Arterial Catheters as a Source of Bloodstream Infection: A Systematic Review and Meta-Analysis. Crit Care Med. 2014.

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Title: What's the Diagnosis?

Category: Visual Diagnosis

Posted: 1/20/2014 by Haney Mallemat, MD

Question

50 year-old male intubated for respiratory distress. Ultrasound is used post-intubation to confirm tube placement and the following images are obtained. What's the diagnosis?

Show Answer

Right main-stem intubation as demonstrated by presence of lung-pulse on the left side

Lung-Pulse

  • Normal lung sliding creates an artifact at the pleural line, as the visceral and parietal pleura slide against one another; this is seen in the M-mode image below for the right lung
  • When a pneumothorax occurs the two pleural become separated and there is loss of this artifact; this is called the stratosphere sign (not shown here)
  • However, when the two pleura are in contact but there is no movement of the pleura (e.g. main-stem intubation on the non-ventilated side) lung-pulse is observed (seen below with arrows)
  • Although there is no ventilation of the affected lung, the lung pulse occurs because there is still cardiac activity that "pushes" the lung into the chest wall from underneath. This creates small periodic movements of the visceral and parietal pleura, creating small amounts of artifact
  • Lung pulse can differentiate pneumothorax from other causes of lung hypoventilation:
    • Mucus plug in main-stem bronchus
    • Foreign body in main-stem bronchus
    • Main-stem intubation

Show References

Follow me on Twitter (@criticalcarenow) or Google+ (+criticalcarenow)



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