All posts by The Trauma Pro

Trauma Chest Tube Tips

I’ve written a lot about chest tubes, but there’s actually a lot to know. And a fair amount of misinformation as well. Here’s some info you need to be familiar with:

  • Chest trauma generally means there is some blood in the chest. This has some bearing on which size chest tube you choose. Never assume that there is only pneumothorax based on the chest xray. Clot will plug up small tubes.
  • Chest tubes for trauma only come in two sizes: big (36Fr) and bigger (40Fr). Only these large sizes have a chance in evacuating most of the clot from the pleural space. The only time you should consider a smaller tube, or a pigtail type catheter, is if you know for a fact that there is no blood in the chest. The only way to tell this is with chest CT, which you should not be getting for diagnosis of ordinary chest trauma. Having said this, there is some more recent literature that suggests that size might not matter as much as we think.
  • When inserting the tube, you have no control of the location the tube goes once you release the instrument used to place it. Some people believe they can direct a tube anteriorly, posteriorly, or anywhere they want. They can’t, and it’s not important (see next tip).
  • Specific tube placement is not important, as long as it goes in the pleural space. Some believe that posterior placement is best for hemothorax, and anterior placement for pneumothorax. It doesn’t really matter because the laws of physics make sure that everything gets sucked out of the chest regardless of position except for things too big to fit in the tube (e.g. the lung).
  • Tunneling the tube tract over a rib is not necessary in most people. In general, we have enough fat on our chest to ensure that the tract will close up immediately when the tube is pulled. A nicely placed dressing is your insurance policy.
  • Adhere to an organized tube management protocol to reduce complications and the time the tube is in the chest.

And finally, amaze your friends! The French system used to size chest tubes is the diameter of the tube in millimeters times three (3.14159, pi to be exact). So a 40Fr chest tube has a diameter of 13.3mm.

Coming This Week: Chest Tube Week

I’m dedicating the coming fortnight (that’s two weeks to you non-Brits) to the lowly chest tube. It’s taken for granted, but there is a lot a variability on how we insert, manage, and pull out these devices. Here’s what’s coming, starting tomorrow:

  • Videos on how to insert a chest tube and pigtail catheter
  • A video on how to pull a chest tube properly
  • Chest tube tips and tricks
  • A practice guideline for chest tube management
  • Troubleshooting chest tubes
  • Collection systems gone bad
  • Lateral chest x-ray for pneumothorax: waste of time?
  • When to remove a chest tube
  • Autotransfusing blood from the collection system

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Diagnostic Tip: Nail Discoloration After Severe TBI

Occasionally, patients who have had a severe brain injury but recovered relatively quickly may present with complaints of odd nail discoloration. This may involve fingernails and/or toenails. What gives?

This is actually a byproduct of repeated exams to determine the Glasgow Coma Scale score. A common way to determine the motor component is to squeeze the fingertip or toetip. I’ve seen some neurosurgeons use a pen to apply a great deal of force to the nail.

The discoloration is a resolving subungual hematoma. You may see different colors under different nails, depending on the age of the hematoma. Amaze your colleagues with your knowledge on this one!

New Technology: Blood Type In 30 Seconds!

This one is really exciting! Blood banks typically keep a significant number of units of O- “universal donor” blood available. These units can be given immediately when a trauma patient in need arrives, since it contains no antigens to the common blood types. It takes anywhere from 5-15 minutes for the blood bank to determine the blood type from the patient’s blood. Then and only then can they begin delivering “type specific” blood that matches the patient’s blood type.

Researchers at the Third Military Medical University in China have developed a paper-based test to determine the ABO type as well as the Rh type (D). Indicators for A, B, and D antigens turn a blue color when they are present, allowing the clinician or blood bank to accurately determine the blood type in 30 seconds. 

Why is this important? O- is an uncommon blood type, with only about 6% of the US population carrying it. Yet blood banks have to keep an inordinate amount in stock “just in case.” Using a blood type test like this could significantly cut down on unnecessary use of this rare O- blood. Unfortunately, it will be 1-2 years before the test is commercially available. I’m sure our nation’s blood bankers can’t wait!

Here’s a brief video that demonstrates how it works.

YouTube player

Reference: A dye-assisted paper-based point-of-care assay for fast and reliable blood grouping. Science Translational Medicine 15 Mar 2017:
Vol. 9, Issue 381, eaaf9209.

How To: Retrograde Urethrogram

I’ve gotten a number of recent requests to repost this easy, DIY guide to the retrograde urethrogram. Enjoy!

One of the hallmarks of urethral injury is blood and the meatus in males. The standard answer to the question “how do you evaluate for it?” is “retrograde urethrogram.” Unfortunately, too few people know how to perform this test, and not all radiologists are familiar. Many times it falls to the urologist, who may not be immediately available.

The technique is simple. This is my variation on the standard technique. The following items are needed:

  • A urine specimen cup
  • A tube of KY jelly (not the little unit dose packs)
  • A bottle of renografin or ultravist contrast
  • A 50-60 cc Toomey syringe (slip-tip)
  • A fluoroscopy suite

Pour 25cc of contrast and 25cc of KY jelly in the specimen cup, cap it and shake well. Draw the contrast jelly up into the syringe. Under fluoro, insert the tip of the syringe into the penis and pull the penis toward yourself, pinching the meatus around the tip of the syringe. Slowly inject all the contrast, watching the contrast column on the fluoro screen. Once there is easy flow into the bladder, you can stop the study. If you see extravasation into the soft tissues, stop the study and call Urology.

The advantages to using this technique are:

  • The contrast/jelly mix creates a contrast gel that is less likely to leak from the meatus when injected
  • The jelly makes it easy to insert the catheter if no urethral injury is detected

Normal urethrogram:

Normal urethrogram

Abnormal urethrogram:

Abnormal urethrogram