Archive | April, 2013

PBJ in left mainstem bronchus…

April 28, 2013

0 Comments

A recent patient who presented after choking on a peanut butter and jelly sandwich…

PBJ in L mainstem CTPBJ in L mainstem CXR

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

Advertisements
Continue reading...

Brain Tumor…

April 25, 2013

0 Comments

Here is an MRI head on a patient with a headache and newly diagnosed brain mass:

MRI brain tumor

This is a T2 weighted MRI.  T2 weighting is particularly good at showing edema.  Simple fluid enhances and appears bright on the image.  Above you can see the tumor arising near the peripheral parietal area with a good amount of surrounding bright fluid consistent with edema.  Note that the edema shows up similar to the patient’s normal CSF in the ventricles. 

If you add contrast to the study (gadolinium) and T1 weight the image this is what you’ll see:

Brain Tumor 2

In T1 weighted imaging simple fluid is darker but in this case the tumor outlines very well with gadolinium.  This imaging is particularly good at picking up smaller tumors without large amounts of surrounding edema.  In this case several other smaller lesions were easily identified with T1 gadolinium imaging including one seen in the midbrain:

Midbrain 1

These turned out to be a metastatic lesions likely from the lung.  Metastases are the most common clinically important brain malignancies found outside of the pediatric population (the exact incidence of non-clinically apparent. 

Author:  Russell Jones, MD

Continue reading...

Free Air…

April 21, 2013

0 Comments

An elderly patient presented with abdominal pain for a week.  The patient had peritoneal signs on exam and thus xray imaging was pursued (see discussion below):

Free air

Image 1

Free air 2

Image 2

Free Air 1

Image 3

This is an acute abdominal series showing free intraperitoneal air in the right upper quadrant.  Notice that it cannot be determined if the patient has free air on the supine view (Image 1).  This is because the air is layering to the anterior portion of the peritoneal cavity.  In order to reveal air in the peritoneum, one must layer it to one of the sides (Image 2 – patient is laying on their left side and the air flows to the right upper quadrant) or upright (Image 3 – patient is upright and the air layers under the diaphragm, in this case the right side). 

I like the acute abdominal series to look for free air in the setting of a highly concerning exam.  You can also just do an upright chest xray.  They are quick and if free air is found it will likely be a study that will change the patient’s course; surgery will in most cases take the patient to the operating room with just an xray for exploratory laparotomy.  In our case, however, surgery was tied up for a bit and this allowed an extra 1/2 hour ED stay, I pursued non-contrast CT to further identify what was going on:

Free Air CT 1

Image 4

Free Air CT 2

Image 5

This CT shows findings highly concerning for a perforated duodenal ulcer.  In Image 4 you can see the air just above the liver edge anteriorly along with free intraperitoneal fluid layering on the side of the liver and spleen.  She also has an aortic aneurysm.  Image 5 shows an area of free air and stranding near the distal duodenum.  Laparotomy revealed a perforated duodenal ulcer, the aortic aneurysm was incidental. 

Author:  Russell Jones, MD

Continue reading...

WWWTP #7 (What’s Wrong With This Picture?)

April 18, 2013

0 Comments

What’s wrong with this chest xray…

R mainstem intubation

This one is not too subtle but a very important chest xray that everyone should see in order to avoid missing the problem!

Answer to follow.

Author:  Russell Jones, MD

Continue reading...

WWWTP #7 (What’s Wrong With This Picture) Answer

April 15, 2013

0 Comments

R mainstem intubation

Answer:  Right mainstem intubation.

The endotracheal tube needs to be withdrawn about 5 cm to be in good position between the carina and thoracic inlet.

Author:  Russell Jones, MD

Continue reading...

Knee dislocation imaging…

April 12, 2013

2 Comments

A couple days ago I asked what other imaging modality is recommended with knee dislocations.  The answer is CT angiogram of the lower extremity.  As you recall we had an image of a patient with a knee dislocation, here is his CT angiogram of the left lower extremity:

CT angiogram LLE

This image shows no evidence of injury to the popliteal artery with contrast reaching the distal vasculature.  Please note that the bolus timing was optimized only for the left side thus the right side is not completely imaged.  Remember this imaging modality in knee dislocations to rule out vascular injury.

I came across an article written in 2007 published in Emergency Medicine Clinics of North America which has a good review section on knee dislocation (1).  The article also discusses other important emergency medicine orthopedic injuries.  According to the article, popliteal artery injury occurs in approximately 40% of high-energy knee dislocations.  Peroneal nerve injury occurs in 14-35% of cases.  Some classic mechanisms of dislocation include when a car bumper strikes the femur above a planted leg and when the knee strikes the dashboard in a high-energy frontal MVC.  Patients with findings consistent with arterial injury need emergent vascular surgery, ideally within 6 hours.  Compartment syndrome can occur and a delay in repair can result in need for amputation.  Furthermore, delayed spasm or compartment syndrome can occur and it is recommended that all patients be observed for 24 hours with serial clinical exams.

Author:  Russell Jones, MD

References

1.  Newton EJ, Love J.  Emergency Department Management of Selected Orthopedic Injuries.  Emerg Med Clin N Am 25; 2007: 763-793.

Continue reading...

Patient fell, now with knee pain…

April 9, 2013

2 Comments

Knee dislocation

This patient has a knee dislocation with an avulsion fragment seen in the joint space.  The tibia/fibula are both rotated facing medial with the patella displaced to the medial side as well.  Lateral projections were unable to be obtained due to the patient being very uncomfortable however clinically the tibia seemed to be posterior to the distal femur. 

Knee post-reduction 2Knee post-reduction 1

MRI later showed complete tears of the anterior and posterior cruciate ligaments as well as the medial collateral and fibular collateral ligaments.  It also showed the tibial plateu fracture and a compression fracture of the distal femur.

What other imaging would you recommend for this patient in the emergent setting?

Author:  Russell Jones, MD

Continue reading...

Necrotizing Fasciitis…

April 6, 2013

1 Comment

Nec Fasc 3

Nec Fasc 2Nec Fasc 1

This patient came in septic with hypotension, tachycardia, obtunded mental status.  A decubitus ulcer was noted stage III with surrounding crepitus and erythema.  There is an impressive amount of gas extending up the fascial planes in the upper left leg, gluteal area, extending through the sciatic foramen into the pelvic cavity.  This is consistent with necrotizing fasciitis and this extent of involvement has a very poor prognosis.  The source was likely a sacral decubitus ulcer. 

Author:  Russell Jones, MD.

Continue reading...

The Chest Xray you never want to see…

April 3, 2013

3 Comments

…but probably most of us have!  One of the senior residents gave me this Chest Xray on a person that came in with cardiac arrest:

T PTX 1

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:

T Ptx 2

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

Continue reading...