All posts by TheTraumaPro

CT Scanning After Gunshot To The Abdomen

Yesterday’s question related to ordering a CT scan in patients with a gunshot to the abdomen. Should it ever be needed? In general, if you encounter this question on an exam, the answer should be no. However, medicine in general and trauma in particular are not so black and white. There are always exceptions to the rules. 

Generally speaking, gunshots to the abdomen have a 90+ percent chance of causing an injury that requires repair. Pretty good odds that the patient needs a laparotomy. However, there are a few cases where further diagnosis may be okay.

In general, additional imaging is warranted if it will change the decision-making process in some way. In most gunshots to the abdomen, decision-making is very straightforward, and the patient must go to the OR without delay.

In some cases, there is a question as to whether or not the patient even needs an operation. The most common situation occurs when the wound could be tangential and completely extraperitoneal. These patients must be hemodynamically stable and without diffuse abdominal pain or tenderness to be considered for CT. Symptoms over the wound tract are acceptable. CT can show very clearly that the bullet stayed away from critical internal structures. These patients may even be discharged if they have no other injuries.

The other case is applicable in select patients with an obvious need for OR and who are hemodynamically stable. If a roadmap provided by CT would potentially cause the surgeon to limit, focus or expand the exploration, the scan may be justifiable. Most commonly, this occurs in patients with multiple gunshots, in whom the exact trajectories can’t be fully appreciated by looking at the holes and the known bullets seen on plain abdominal images.

Bottom line: CT scan in patients with gunshots to the abdomen should be a rare occurrence. There must be specific indications, and the patient must be hemodynamically stable. If the result may change the procedure in some way, it may be justifiable. Just be ready to explain your rationale to your trauma medical director! They will ask!

Pop Quiz: CT Scanning After Gunshot To The Abdomen

Gunshots to the abdomen have a very high likelihood of causing damage that needs to be repaired. For this reason, the vast majority are immediately transported to the OR for laparotomy (celiotomy). 

But there are a few situations in which advanced diagnostics can be justified prior to operation. Do you know what they are? Tweet or comment your answers. I’ll explain the details tomorrow.

The May Trauma MedEd Newsletter Is Available!

The April newsletter is now available! Click the image below or the link at the bottom to download. This month’s topic is TBI. 

In this issue you’ll find articles on:

  • Is the GCS scale getting too old?
  • Non-surgeons placing ICP monitors
  • Management of CSF leaks
  • Pneumocephalus and air transport
  • Fever and head injury

Subscribers had the newsletter emailed to them over the weekend. If you want to subscribe (and download back issues), click here.

Download the newsletter here!

Are Inlet / Outlet Views Obsolete In Pelvic Trauma?

Orthopedic surgeons have long found inlet and outlet views (I/O) of the pelvis to be helpful in their management of pelvic fractures. However, for the last decade we’ve seen an inexorable creep in diagnostic imaging from plain xrays to computed techniques. Have the conventional inlet and outlet views lost their luster?

San Francisco General Hospital and UCSF recently published a registry-based study looking at conventional pelvic I/O images and virtual I/O images reconstructed from CT scans. Two years of registry data were reviewed, and included patients had both conventional I/O images and CT imaging. Images were evaluated by two orthopedic traumatologists for their quality.

Sadly, only 20 patients were available for this study, which makes it an interesting pilot at best. The most interesting results were as follows:

  • Quality of imaging was judged to be equal except when pelvic rotation was present. CT fared better in these cases.
  • Both inlet and outlet views were judged to be better when reconstructed by CT
  • Overall, imaging of all portions of the pelvis was about equal in both types of study
  • The need for repeat studies was identified in nearly half of conventional images, but in only 8% of CT images

Bottom line: CT scanning is slowly becoming the preferred modality for just about any type of trauma imaging. In the 1980’s, head CTs became widespread, followed rapidly by abdominal imaging. Chest CT for definitive diagnosis became commonplace around 2000, and spine imaging by CT has now become the gold standard. Although there are a few throwbacks where conventional imaging has been thought to be better, they are vanishing rapidly. Computing technology can now reconstruct inlet and outlet views of the pelvis, correcting for rotation and angulation in any study of the abdomen/pelvis. And if the reconstructed image is not quite right, the tech can change a few parameters and generate it again and again until the image is perfect. 

Orthopedic surgeons should now expect a nicely formatted set of inlet/outlet CT reconstructions in all trauma patients with pelvic fractures.

Related post:

Reference: Are conventional inlet and outlet radiographs obsolete in the evaluation of pelvis fractures? J Trauma 74(6):1510-1515, 2013.

Placement of ICP Monitors By Non-Neurosurgeons

Traumatic brain injury (TBI) is a common injury world-wide, but neurosurgeons are scarce. Traditionally, neurosurgeons are the ones to place invasive monitors to watch intracranial pressure (ICP). But what about injured people who are taken to a hospital where there is no available neurosurgeon?

A group at Wichita, Kansas looked at their 10 year experience with ICP monitor placement, where it can be done by neurosurgeons, trauma surgeons or general surgical residents (under trauma surgeon supervision). A total of 63 were placed by neurosurgeons, 30 by trauma surgeons, and 464 by residents under supervision. The usual demographics, including hospital stay, were the same across groups. There were essentially no significant differences based on who placed the monitor. Curiously, the article does not state whether the monitors were extradural or intraventricular, or both. The discussion section alludes to the fact that they were “parencyhmal.”

There were only three iatrogenic bleeds, and all occurred with resident placed monitors. None were clinically significant. Malfunction rate was about 5% across all groups. Monitors had to be replaced at some point in about 11% of all three groups. One CNS infection occurred in a patient with a resident-placed monitor.

Bottom line: With proper training and supervision, ICP monitors can be placed by just about anyone. This is particularly important in more rural locations where there are few if any neurosurgeons. But as always, this process needs to be monitored carefully by the hospital’s Trauma Performance Improvement / Patient Safety program (PIPS).

Related posts:

Reference: Placement of intracranial pressure monitors by non-neurosurgeons: excellent outcomes can be achieved. J Trauma 73(3):558-563, 2012.