All posts by TheTraumaPro

The Deep Sulcus Sign

Pneumothorax is frequently difficult to diagnose in the resuscitation room. Sometimes it is obvious, with a hypoxic patient and absent breath sounds. But not usually. Most of the time we rely on a chest xray to help make the diagnosis.

Unfortunately, the good old chest xray only shows a pneumothorax about 30-50% of the time. A big part of the problem is that our patients are usually supine to protect their spine. A small pneumothorax make float anteriorly in the supine position, and if it is not big enough to wrap around the lateral edge of the lung, it may remain invisible. So you need to look for gross and subtle signs on the image that will help make the diagnosis. The deep sulcus sign is one of the more subtle signs. 

Simply stated, the deep sulcus sign is a radiolucent (dark) lateral sulcus where the chest wall meets the diaphragm. The amount of lung in this area is less, so a small amount of air will tend to darken the area making it more prominent. Look at patient left in the left photo, and compare to their right side. It is much darker and appears to extend lower than usual. In more extreme cases, the amount of air just above the diaphragm may make it appear inverted (right photo).

Bottom line: If you see a deep sulcus sign on the chest xray image, strongly consider pneumothorax. If the patient begins to have hemodynamic problems, needle the chest and chase with a chest tube. If they remain stable, the patient will still require a chest tube. Chest xray always underestimates the true size of the pneumothorax. Place the usual size chest tube and manage per your usual protocol. And, as always, use your best sterile technique and definitively identify the proper side before placing the tube.

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Trauma Survival and Air vs Ground Transport

Wartime experience has shown that rapid transport from the battlefield scene of injury to definitive care dramatically improves survival. This has been translated into civilian trauma care by making helicopter transport to a trauma center more widely available. But this resource is still somewhat limited, and very expensive compared to ground EMS transport. Is this expense warranted, or in other words, does it improve survival?

Many have tried to answer this question. Several of these studies did show improved survival with air transport, but most had significant flaws that made their conclusions hard to interpret. The current issue of JAMA has published an article from MIEMSS and Johns Hopkins that tries to do it right.

The authors used the National Trauma Data Bank (1.8M records) and whittled it down to 223K by using pertinent exclusion criteria. About 25% were transported by air and 72% were taken to Level I centers (vs Level II). A sophisticated regression model was used to adjust for missing data and clustering by trauma centers.

They found that there is roughly a 1.5% survival advantage in taking patients to trauma centers by air. About 65 patients need to be transported to a Level I center, or 69 patients to a Level II center, to save a life. There are some issues with the statistics, primarily due to the nature of the NTDB data, but overall the paper is nicely done.

Bottom line: It looks like helicopter transport of seriously injured trauma patients conveys a very small survival advantage. However, this does not mean that everybody now needs to be flown in. This is not an ideal world, and not everybody is in an area that can provide such transport. Furthermore, in many areas ground EMS is still faster than air. And finally, air transport is much more expensive than the incremental survival increase may be worth. We will have to come to grips as a society to figure out what we can really afford.

Reference: Association between helicopter vs ground emergency medical services and survival for adults with major trauma. JAMA 307(15):1602-1610, April 18, 2012.

What The Heck? The Answer

The photo on Friday shows a woman who had been run over by her own car. The vehicle had rolled over her pelvis and stopped, requiring extrication. The most likely injury is an open book pelvic fracture with significant diastasis and/or bilateral unstable sacral fractures.

If you see this clinical presentation there are several things you need to do immediately:

  1. Call for blood. Losses will be large, so you may even want to consider activating your massive transfusion protocol.
  2. Call an orthopedic surgeon. External stabilization will be needed to help decrease blood loss.
  3. Consider early intubation for control of pain. You will be doing a lot, and a patient in agony will slow you down. Your patient is already hypovolemic, so plan your drug choices accordingly.
  4. Search for evidence of an open fracture. Do a good rectal and vaginal exam looking for blood.

The pelvic xray is poor quality, but shows the major problem, a 10cm pubic diastasis from the open book pelvis fracture. Wrapping the pelvis may be of some help, but consult your orthopedic surgeon first. This pelvis is probably not connected to the spine anymore, so wrapping may have variable results.