Tag Archives: neck

Management Of Penetrating Neck Trauma: The Future?

In my last post, I described the evolution of the classic approach to penetrating neck injury. Today, I’ll propose a new way of managing it based on a combination of physical exam and CT scan.

This proposal is based on the high degree of accuracy that CT angiography of the neck provides. It is very sensitive for identifying even small injuries to the aerodigestive tract and vascular system. This study is based on work done at LA County – USC Hospital several years ago.

The trauma group at LAC+USC organized a prospective, multicenter study using a multidetector CT angiography of the neck for initial screening of penetrating neck injury. This allows evaluation the neck as a single unit, not as three zones. It also solves the problem of trying to apply zones to injuries that cross several of them.

The new algorithm that was tested utilized an initial physical exam, first looking specifically for “hard signs” of injury.  The following were considered the hard signs:

  • Active hemorrhage
  • Expanding or pulsatile hematoma
  • Bruit or thrill over the injured area
  • Unresponsive shock
  • Hemoptysis or hematemesis
  • Air bubbling from the wound

These patients were immediately taken to the OR and explored through an appropriate incision.

Patients with no signs or symptoms were admitted and observed for at least 24 hours. All other patients were considered to have “soft signs.” They underwent multidetector CT angiography of the neck, with a scanner having at least 40 slices. Further evaluation of these patients was based on the exam and CT scan.

Here are the factoids:

  • 453 patients with penetrating neck injury were identified during the 31 month study period
  • 9% had hard signs and were taken to OR; 50% had soft signs are underwent CT; 41% had no signs and were observed
  • For soft sign patients, 86% of scans were negative and all were true negatives after observation
  • 12% of soft sign patients had a positive scan, and of those 81% were true positives
  • 4 patients (2%) with soft signs had too much artifact for an accurate CT and other tests were performed; 1 of the 4 had an injury
  • Sensitivity of CTA was 100% and specificity was 97.5% in the soft sign patients
  • The authors concluded that CTA is very reliable for identifying injuries in patient with soft signs, and that patients with no signs do not require scanning, only observation

Bottom line: This is an intriguing paper that takes advantage of both physical examination at CT angiography. The results are impressive, but the numbers are still relatively small. It lends support to the argument that CTA is not required in all stable patients. But I can’t recommend completely changing our practice yet based on this one study. Additional numbers are certainly needed, but I suspect that this will become the norm in the future. I would also recommend that we all carefully look at our diagnostic algorithms to see other areas where we might identify and eliminate unneeded imaging, labs, etc.

Reference: Evaluation of multidetector computed tomography for
penetrating neck injury: A prospective multicenter study. J Trauma 72(3):576-584, 2012.

Management Of Penetrating Neck Trauma: The Way We Were/Are

The management of penetrating injuries to the neck has changed very little over the years. Could it be time? Today, I’ll review some of the basics of classic diagnosis and treatment. In my next post, I’ll discuss an alternative way to approach it.

First, lets look at the time-honored zones of the neck. Here’s a nice diagram from EMDocs.net:

The zones are numbered in reverse, from bottom to top, and in Roman numerals.

The area below the cricoid cartilage is considered Zone I and contains many large vascular and aerodigestive structures that are relatively difficult to approach surgically. For this reason, diagnostic testing is recommended to assist in determining if an operation is actually needed and what the best surgical exposure would be. Obviously, this can only be considered in the stable patient. Unstable patients must go straight to the OR and the trauma surgeon will determine the surgical approach on the fly.

Similarly, the area above the angle of the mandible is Zone III, and is also difficult to expose. Injuries to this area may involve the distal carotid and vertebral arteries near the base of the skull, as well as the distal jugular vein. Surgical approach may require dislocation of or fracturing the mandible to get at this area. This is  challenging and not that desirable, and few surgeons are familiar with the technique. For this reason, imaging is very desirable and often demonstrates that no significant injury is present. And endovascular / angiographic techniques are now available that may obviate the need for surgery.

Zone II is everything in-between the mandibular angle and cricoid cartilage. This is the surgical Easy Button. Exposure is simple and the operation is fun. In the old days, an injury to this area went straight to the OR regardless of whether there were signs or symptoms of injury. Yes, there were quite a few negative explorations. But we’ve become more selective now with the advent of improved resolution of our CT scans.

Currently, we usually follow a two-step approach to penetrating neck trauma:

  1. Are there hard signs of injury present? These tell us that a structure that absolutely needs to be fixed has been injured. The patient should be taken directly to OR after control of the airway, if appropriate. Typical hard signs are:
    1. Airway compromise
    2. Active air bubbling from wound
    3. Expanding or pulsatile hematoma
    4. Active bleeding
    5. Hematemesis
  2. What zone is the injury in? And don’t just look at the obvious entry point. Gunshots (and long knives) may enter multiple zones. The zone then determines what happens next:
    1. Zone I – CT angio of neck and chest. If positive, proceed to OR for repairs, and perform EGD and/or bronchoscopy as needed
    2. Zone II – Old days: proceed to operating room for exploration, or angiogram, EGD, direct laryngoscopy, and bronchoscopy. Most chief residents chose the former. Current day: CTA of neck, followed by OR, EGD, bronchoscopy only if indicated.
    3. Zone III – CT angio of the neck. If positive, consider angiography/endovascular consultation vs operation.

Changes from old days to more current thinking have been made possible by improvements in speed and resolution of our CT scanners. But why can’t we take this another step forward and streamline this process even more? I’ll propose some changes in my next post!

Reference: Western Trauma Association Critical Decisions in Trauma:
Penetrating neck trauma. J Trauma 75(6):936-940, 2013.

AAST 2011: CT Evaluation of Penetrating Neck Trauma

In the old days, stab injuries to Zone 2 in the neck meant a trip to the operating room. Then it became acceptable to evaluate stable patients with this injury via endoscopy, angiography and a swallow study. Most chief residents didn’t have the patience for this and opted for OR anyway. CT now promises to simplify the evaluation process, rolling these studies into one fast and simple one.

USC+LAC and the University of Maryland directed a prospective multicenter study that looked at the sensitivity and specificity of using CT angiography of the neck to evaluate penetrating injuries.All patients underwent a structured physical examination of the neck. If hard signs of injury to the vascular tree or aerodigestive tract were present, they were immediately taken to OR (6%). Nearly all of these patients had an injury that required repair. If they had no signs, they were merely observed (51%). None had a missed injury.

The remaining 159 patients had a positive exam (minor oozing, small stable hematoma) underwent CT angio of the neck (54% stabs, 42% gunshots, 4% other). The majority were in Zone 2 (41%), but 24% were in Zone 3, 21% in Zone 1, and 14% crossed multiple zones. Overall sensitivity was 100% and specificity was 97%. CT angio was nondiagnostic in 3 patients due to missile fragment artifact.

Bottom line: CT angio of the neck is a fast and accurate exam that can be used in stable patients with an abnormal physical exam but no hard signs of injury. This fits my bias, and we have already been using the scanner this way for stabs. I would now recommend cautiously extending its use for select gunshots as well.

Hard signs of neck injury:

  • Unstable vital signs
  • Large, expanding, or pulsatile hematoma
  • Active bleeding
  • Air bubbling
  • Voice or airway disturbance
  • Hematemesis / hemoptysis
  • Thrill / bruit
  • Neurologic deficit

Reference: Evaluation of multidetector computed tomography for penetrating neck injury: a prospective multicenter study. AAST 2011 Annual Meeting, Oral Paper 61.