Tag Archives: vascular

Using CT To Diagnose Extremity Vascular Injury

The traditional gold standard for diagnosis of vascular injury to the extremities has been a good physical exam plus conventional catheter angiography. However, using angiography always adds a layer of complexity and risk to patient care. The interventional team may not be immediately available after hours, there is typically a road trip within the hospital to deliver the patient for the study, and overall it is quite expensive.

With the advancements we have seen in CT angio techniques and scanner technology, some centers have been using computed tomography to evaluate for vascular injury. A few small retrospective studies have been done, but this month a larger prospective study was published.

Over a 20 month period, 635 patients with extremity trauma and a suspicion for vascular injury were entered into the study. A structured physical exam was performed, and any patient with “hard signs” of vascular injury were taken to the OR. 527 patients had no signs of vascular injury and were observed and released. The remaining 73 (most had soft signs of vascular injury) underwent CT angiography of the extremity.

The sensitivity and specificity of this test were 82% and 92%, respectively. Positive and negative results were nearly perfectly predictive. However, approximately 10% were inconclusive, usually due to bullet artifact or reformatting errors. These patients either underwent confirmatory conventional angiography or operation.

Bottom line: Angiography using multi-detector CT scanners is an excellent tool for evaluating potential extremity vascular trauma from penetrating trauma. The technology is available around the clock without a wait, and usually does not involve lengthy trips through the hospital. A good physical exam is imperative so patients with hard signs of injury can go straight to the OR. Equivocal studies must be evaluated further by conventional angio or an operation.

Reference: Prospective multidetector computed tomography for extremity vascular trauma. J Trauma 70:808-815, 2011.

Splenic Vascular Blush

Contrast blush is always a concern when seen on CT of the abdomen for trauma. It can represent one of two things, and both are bad:

  • Active extravasation of contrast
  • Splenic pseudoaneurysm

These two clinical issues can be distinguished by looking at the location of the contrast and its persistence. A pseudoaneurysm is located within the parenchyma, and the contrast will wash away, so it will not be visible on delayed images. Contrast that extends beyond the parenchyma or persists in delayed views represents active bleeding. In either case, the failure rate of nonoperative management exceeds 80% in adults without additional measures being taken.

Clinically, these patients usually act as if they are losing volume and require additional crystalloid and/or blood transfusion. The natural history in adults is for bleeding to continue or for the pseudoaneurysm to rupture, resulting in a quick trip to the operating room.

If vital signs can be maintained with fluids and blood, a trip to interventional radiology may solve the problem. Selective or nonselective embolization can be carried out and patients with only a few bleeding points can be spared operation. However, if multiple bleeding areas are seen, it is probably better to head to the OR for splenorrhaphy or splenectomy.

The image below shows likely areas of extravasation. They are a bit large to be pseudoaneurysms.

Spleen Blush-CT

Children are different than adults. Extravasation from spleen injuries in prepubescent children frequently stops on its own. Angiography should only be used if the child is failing nonoperative management.