This was an interesting case because of the post-intubation conundrum we faced.  The patient came in peri-arrest from hypoxia, GCS was 3 with very poor respiratory effort and oxygen saturation of 60%.  Therefore we were unable to get a great respiratory exam prior to intubation.  Bag-valve mask ventilation with 100% oxygen did not improve the situation and the patient was very difficult to bag due to obviously increased airway pressure.  The intubation was very difficult and as we were checking for bilateral breath sounds post-intubation, we noticed none on the left side.  Capnography color change was good, no gastric sounds were heard, and moisture was in the tube.  Pulling back the endotracheal tube did not change the lack of left sided lung sounds.  The patient continued to be difficult to bag with hypoxia very slowly improving from initial saturations in the 60s now to the mid-70s.  At this point all of our heart rates were around 150 and we had that sinking feeling that occurs when oxygenation doesn’t improve after intubation.

For a few minutes we were concerned about pneumothorax on the left side.  As you can tell from the xray our external landmarks such as tracheal deviation, jugular venous distention were severely limited by body habitus.  Bedside ultrasound using the linear probe was limited as well and no lung-sliding was visualized.  We basically couldn’t identify what we were seeing on ultrasound (later we found out the lung was completely collapsed and we may have been seeing diaphragm, heart, and non-aerated lung).  In the heat-of-the-moment the ED treatment team was perplexed on how to rule out a tension pneumothorax in this situation.

Luckily the patient’s oxygenation creeped above 90% and the patient didn’t have any blood pressure problems.  We took a deep breath, relaxed, and made the decision to obtain the above portable chest xray before performing empiric thoracostomy.  This turned out to be the correct decision as she had a complete obstruction of the left mainstem bronchus from aspiration of a peanut-butter sandwich.  CT chest (above) shows the obstruction at the level of the carina with collapse of the left lung.  Bronchoscopy was performed and a large amount of peanut butter, jelly, and sandwich fragments were removed with improvement in the patient’s chest xray post-procedure.

Moral of the story:  not all patients have pneumothorax or a malpositioned endotracheal tube when lung sounds are absent.

A brief alternative differential diagnosis when a patient has absent lung sounds on one side:

1. Mainstem bronchus obstruction or compression
2. Diaphragmatic hernia
3. Large pleural effusion
4. History of pneumonectomy

I’ve noticed a trend in ED training toward increased reliance on bedside ultrasound.  It is important to realize that if you are going to use ultrasound in the resuscitation decisions such as this, make sure that you are seeing something that reliably indicates the pathology you are seeking to correct.  We did not see signs that supported or refuted pneumothorax and thus the ultrasound was non-diagnostic.  I apologize for not having the ultrasound images.  We forgot to save them as we all had that panicked feeling when you’ve intubated someone and their pulse ox isn’t improving very fast!

Author:  Russell Jones, MD

This Chest Xray demonstrates a large pneumothorax on the right side with tension phenomena.  Tension Pneumothorax is when the air trapped in the pleural space places pressure on the mediastinal structures and you see a shift of the mediastinum in the opposite direction.

Physiologically this means that the anatomy has changed and blood flow back to the central circulation is limited by not only mechanical obstruction but increased intrathoracic pressure.

After thoracostomy:

Remember, tension pneumothorax is one of the 5h’s and 5T’s that cause cardiac arrest.  However, its unclear if this is a post CPR pneumothorax or if this was the cause of the cardiac arrest.  You can see some deformities suspicious for rib fractures mid-way down the right lung fields.  There was no indication of trauma in the patient’s presentation so these may be old or a complication of chest compressions…this could be a source of pneumothorax as well as the positive-pressure from endotracheal intubation.  Incidentally, the chest tube is inserted slightly far with kinking in the upper lung but it appears to be working with reexpansion and relief of the tension phenomena.

Author:  Russell Jones, MD

Image Contributor:  Ryan Hunt, MD

The interesting portion of this radiograph is the overall hyperinflation of the right lung when compared to the left.  With this clinical history, asymmetric hyperinflation is highly concerning for aspirated foreign body.  The foreign body acts as a “ball-valve,” trapping air on exhalation and therefore causing a hyperinflated lung.  It can, but often doesn’t lead to pneumothorax. 

In this case the asymmetry was visible on upright radiograph and the diagnosis of retained foreign body was made.  The child had a bronchoscopy and an apple fragment was pulled out of his right mainstem bronchus. 

Other imaging tricks in aspiration include decubitus films and expiratory films. 

1.  Expiratory films:  have the patient expire and take a plain upright radiograph.  This may accentuate the asymmetry if the ball-valve effect is causing air trapping.

2.  Decubitus films:  When laying on one’s side the dependent lung should be asymmetrically smaller than the opposing lung.  If one of the lungs stays symmetric while in the dependent position, this can be a sign of air trapping.  It is recommended to obtain films in both decubitus positions (left and right).

Also consider CT imaging as a final imaging modality.  However, the definitive study is bronchoscopy if your suspicion is high. 

Author:  Russell Jones, MD

Image Contributor:  Kendra Grether-Jones, MD

In this image the left heart border is obscured and there is an infiltrate taking up airspace in the left lower lung.  That’s it, nothin’ fancy about it.

The symptoms of pneumonia described by Hippocrates (c. 460 BC – 370 BC) (1):

Peripneumonia, and pleuritic affections, are to be thus observed: If the fever be acute, and if there be pains on either side, or in both, and if expiration be if cough be present, and the sputa expectorated be of a blond or livid color, or likewise thin, frothy, and florid, or having any other character different from the common… When pneumonia is at its height, the case is beyond remedy if he is not purged, and it is bad if he has dyspnoea, and urine that is thin and acrid, and if sweats come out about the neck and head, for such sweats are bad, as proceeding from the suffocation, rales, and the violence of the disease which is obtaining the upper hand.

Begs the question:  what does “purged” mean?

Author:  Russell Jones, MD

References

1.  Pneumonia History. http://www.news-medical.net/health/Pneumonia-History.aspx

This CT shows swelling and edema in the epiglottis.  CT imaging of this diagnosis can occur in the STABLE epiglottitis patient.  It will likely be a patient with unclear pathology and identified on CT rather than a easily clinically identified epiglottitis.  Why?  Because clinical epiglottitis that is very clearly identified is an airway emergency and they don’t end up in the CT scanner.  The classic appearance will be a patient in the “tripod” position, drooling, stridor, hoarse voice, and looking ill.  Lateral soft-tissue plain films can also make the diagnosis.  Usual suspects causing epiglottitis include:  H. Influenza, S. Aureus, Streptococcus sp., and Moraxella Catarrhalis (1).

Epiglottitis affects both children and adults and should be on your differential in an adult with these symptoms.  Since childhood vaccinations have become widespread in developed countries the incidence of childhood epiglottitis has decreased.  The incidence has remained stable in adults.  This patient is interesting because of the un-immunized status.

Some thoughts pertaining mainly to children:

CT imaging of the neck in children is a controversial subject.  Remember that the thyroid gland is anatomically present in the radiation area and the future risk of thyroid malignancy isn’t quite known.  You must weight the risk of radiation against the benefit of the imaging test in this situation.  CT is very good at detecting and characterizing childhood illnesses such as peritonsillar abscess, retropharyngeal abscess, and epiglottitis.  If you highly suspect one of these pathologies CT is usually warranted as these diagnoses can cause significant morbidity and will many times need intervention.  Keep in mind, however, that soft tissue neck plain radiographs may give you enough information to direct management and has much less radiation burden.

Some radiology signs are applicable to epiglottitis:

1.  Thumbprint sign:  on lateral CT or Plain film the epiglottitis will resemble a thumb in shape and size rather than the expected thin appearance.  This is present on the CT above.

2.  Halloween sign:  describes the usual appearance of the epiglottis on CT axial cut.  See image on Wikipedia®.  Halloween Sign.

Author:  Russell Jones, MD

Image Contributor:  James Chenoweth, MD

References

1.  Epiglottitis. http://www.wikipedia.org.

This is a great example of a right middle lobe (RML) pneumonia.  Some features that help distinguish the lobe include:

The right diaphragm is visible.  The lobe overlying the diaphragm is the lower lobe and a RML will sometimes not “silhouette” the right diaphragm.  ”Silhouette” is when a radiographically dense material such as fluid comes into contact with another radiodense thoracic structure such as the diaphragm.  Silhouetting can be seen with the right heart border.  Thus, this fluid on the xray is touching the right heart border but not the diaphragm.  The lobe that corresponds with this is the RML.

A lateral radiograph can also help you identify which lobe is involved (not provided here).

Author:  Russell Jones, MD

What findings on Chest Xray are consistent with viral pneumonia?

Viral respiratory infections commonly cause an “interstitial” pattern on Chest XR.   Interstitial patterns can also be found in atypical bacterial pneumonia from organisms such as Bordatella pertussis, Chlamydia pneumonia, and Mycoplasma.  Findings include peribronchial cuffing, perihilar infiltrates or “haze”.  Peribronchial cuffing can be seen on the XR above:

Other findings in interstitial patterns can include fluid in fissures, bands of atelectasis.

Bronchioles are usually very difficult, if not impossible to identify in cross-section on a Chest XR.  They look like a small clear circle with a thin wall.  However, when they are inflammed and have surrounding edema peribronchial cuffing occurs.  Basically you see a dense fluid around an air-filled bronchiole.  This can be seen in asthma, viral illnesses, heart failure, pertussis, and other pathology (1).  Here is a link to a good web image of peribronchial cuffing close up and on crossection:

http://www.torontonotes.ca/interstitial-disease/peribronchial-cuffing

It is important to note that the Chest XR can support your diagnosis of viral respiratory infection but it is not 100%.  Keep in mind the atypical organisms and prescribe antibiotics if highly suspicious.  Prescribing antibiotics in respiratory infections is a controversial topic with many different thoughts and practice patterns.  I’m not going to poke that sleeping bear…

Author:  Russell Jones, MD

References

1.  Broder JS.  Diagnostic Imaging for the Emergency Physician.  Elsevier 2011.  Pg. 241.

Two calcified nodules can be seen in the lateral R mid lung field.  These are not the cause of the patient’s ED presentation and referred to as “incidental” findings on her Chest XR.

Incidental findings of nodules on Chest XR are a very common ED problem.  What do we do with these?  It turns out this is a very complicated question.  Here is a quick summary of solitary pulmonary nodules (SPN):

The Problem

The incidence of SPN detected by Chest XR in the United States is estimated at 150,000 times per year (1).  Malignancy is the highest concern in these patients, many of which are amenable to discharge.  Lung cancer is the number one cause of cancer-related deaths worldwide, estimated at 1.38 million per year (2).  It is often silent and only discovered when it is extensive and has a poor prognosis of survival.  Nodule-forming cancer is likely to be metastatic or non-small cell lung cancer (NSCLC).  If you’ve discovered a primary lung cancer (NSCLC) and it is stage I, the 5-year survival rate is very high if treated.  However not all of these nodules are malignant.  Herein lies the problem:  who do we work up for these nodules and what is the follow-up we should recommend from the ED?

I did some searching for help and found two evidence-based guidelines discussing SPN management:

American College of Radiology (ACR)

What do the radiologists recommend?  Here is a link to the ACR recommendations on further imaging in SPN:

ACR SPN Guidelines

American College of Chest Physicians (ACCP)

The ACCP also weighs in on SPN management with open access guidelines from 2007:

ACCP SPN Guidelines

Reading these guidelines can help formulate a plan for your patient based on risk profiles, nodule characteristics, and suspicion of malignancy.  I would encourage you to read these so that a plan can be made if you are discharging anyone with an incidental finding of SPN.  My advice:

1.  Show them the nodule and mention the word “cancer.”  I prefer the statement “we need to make sure this isn’t cancer.” In my experience this causes a brief state of shock followed by motivation to listen to your follow up plan.   Be prepared to explain to them why you aren’t admitting them to the hospital.

2.  Explicitly discuss and write down a follow up plan with the patient and/or patient representative.  Make sure this plan is documented in your record.  Missed follow-up of these nodules could cause a early malignancy with a good prognosis to progress to a large malignancy with a poor prognosis.  This is not only bad for the patient but is a significant source of litigation for ED providers.  I usually refer them to primary care and tell them to take my discharge instructions to the provider.  On the discharge papers I provide a description of the nodule and any radiologist’s impression and recommendations.

3.  If you need further information on differential, timing and choice of further studies, etc. call your in-house radiologist and have them give you some recommendations and/or follow the guidelines above.

Author:  Russell Jones, MD

References

1.  Kanne JP, Jensen LE, Mohammed TH, et. al. ACR Appropriateness Criteria® radiographically detected solitary pulmonary nodule. [online publication]. Reston (VA): American College of Radiology (ACR); 2012.

2. Ferlay J; Shin HR, Bray F et al. Estimates of worldwide burden of cancer 2008: GLOBOCAN 2008.  International Journal of Cancer 127 (12): 2893–2917.

3.  Weinberger SE.  Diagnostic evaluation and management of solitary pulmonary nodules.  www.uptodate.com.  Sept. 14, 2012.

4.  Gould MK, Fletcher J, Iannettoni MD et al.  Evaluation of Patients with Pulmonary Nodules:  When is it Lung Cancer?:  ACCP Evidence-Based Clinical Practice Guidelines (2nd Edition).  Chest.  Sept. 2007; 132(Supplement 3): 108S-130S.

Author:  Russell Jones, MD

This ETT is in great position on the AP chest radiograph.  Every ETT should have a radiopaque line extending to the tip in order to identify the tube length.  Ideally the tip of the ETT (arrow) should be midway between the thoracic inlet (top dotted line) and the carina (bottom dotted line).  Some pointers:

• The thoracic inlet on chest XR is roughly at the level of the clavicles.  Anatomically it is the superior portion of the manubrium anteriorly.  This is the level of the subglottis area and upper trachea.
• The carina is usually located around T5-T7 and is usually easily identified on chest XR.  If you have difficulty draw a line from the inferior main bronchi and they intersect at the carina.
• The ETT in a normal adult can advance and retract up to 2cm with neck flexion and extension.  Therefore it is recommended that the ETT is at least 2cm from the carina and 2cm from the thoracic inlet.
• Most commonly the ETT will be placed in the right mainstem bronchus if placed improperly in the airway.
• Signs that the ETT is in the esophagus include a dilated, air filled stomach and esophagus.  And…oh yeah…the patient may not be doing well.
• With digital imaging it is easy to play with the intensity if you cannot identify the tube or carina.  Also, inverting the image to a “negative” image can sometimes help.

Author:  Russell Jones, MD