All posts by TheTraumaPro

Warm Water Immersion Policy for Hypothermia

A few days ago, I wrote about using a therapy tank for immersion to rapidly rewarm patients (click here to read it). Since this type of management usually means moving out of the ED to a separate patient care are, it is important to have a policy that spells out responsibilities for all personnel involved. 

Click here or click the image above to download a copy of the Regions Hospital Trauma Program policy.

Trauma 20 Years Ago: CT Imaging of the Aorta

CT scan is now the standard screening test for injury to the thoracic aorta. But 20 years ago, we were still gnashing our teeth about how to detect this injury.

An interesting paper was published in the Journal of Trauma 20 years ago this month on this topic. Over a 2 year period, the Medical College of Wisconsin at Milwaukee looked at all patients who underwent imaging for aortic injury. At the time the gold standard was aortogram. They looked at patients who underwent this study and CT, which was not very common at the time.

They had 50 patients who underwent aortography alone and 17 who underwent both tests. Of the 17, 5 had the injury, but only three were seen on CT. There were also two false positives. Sensitivity was 83%, specificity was 23%, with 53% accuracy. The authors concluded that any patients with strong clinical suspicion of aortic injury should proceed directly to aortogram.

Why the difference today? Scan technology and resolution has increased immensely. Also, the timing of IV contrast administration has been refined so that even subtle intimal injuries can be detected. CT scan is now so good that we have progressed from the CV surgeon requiring an aortogram before they would even consider going to the OR, to the vascular surgeon / interventional radiologist proceeding directly to the interventional suite for endograft insertion.

Solid Organ Injury: How Soon Can We Begin Chemical DVT Prophylaxis?

Nonoperative management of solid organ injury is the norm, and has reduced the operative rate significantly. At the same time, the recognition that development of deep venous thrombosis (DVT) in trauma patients is commonplace creates uncertainty? Is it safe to give chemical prophylaxis with low molecular weight heparin (LMWH)? How soon after injury?

The trauma group at USC+LAC recently published the findings of a retrospective review of 312 patients undergoing nonoperative management for their liver, spleen or kidney injuries. They looked at chemical prophylaxis administration and its relationship to failure of nonop management of solid organ injury.

As expected, as the grade of the solid organ injury increased, so did the failure rate of nonoperative management. Administration of low molecular weight heparin, such as enoxaparin, did not increase failure rate in this study. All but one failure occurred in patients who had not yet received the injections. Likewise, two DVT and two pulmonary embolisms occurred, but only in patients who had not yet received prophylaxis. 

Bottom line: This small study offers some assurance that early prophylaxis is okay, and a few prospective studies do exist. UCSF / San Francisco General is comfortable beginning chemical prophylaxis 36 hours postop, regardless of solid organ injury. Look for more guidance on this issue in the coming year or so. Until then, consider starting LMWH prophylaxis early to avoid complications from DVT or PE.

Reference: Thromboembolic prophylaxis with low-molecular-weight heparin in patients with blunt solid abdominal organ injuries undergoing nonoperative management: current practice and outcomes. J Trauma 70(1): 141-147, 2011.

Is Too Much Crystalloid a Bad Thing?

All trauma centers have massive transfusion protocols, and they typically spell out the approximate ratios of blood to plasma to platelets. But they do not address the use (or overuse) of crystalloid during these large volume resuscitations.

A multicenter, prospective study was carried out looking at the outcomes after resuscitation from hemorrhagic shock using massive transfusion (at least 10u PRBC in 24 hrs). The patients were severely injured (average ISS 34), and overall mortality and incidence of multi-organ failure was 21% and 65%, respectively. The median amount of crystalloid given was 17 liters, and median red cell transfusion was 14 units in 24 hours.

The authors found that if the crystalloid to PRBC ratio exceeded 1.5:1, morbidity increased significantly. The incidence of multiple organ failure doubled, ARDS tripled, and abdominal compartment quintupled! The authors suggested further research, and did not provide specific strategies for decreasing early crystalloid.

Bottom line: As expected, giving so much crystalloid that we turn people into the Sta-Puft Marshmallow Man is not good. While waiting for additional research, it is probably prudent to try to rapidly achieve definitive control of bleeding and apply gentle use of pressors to decrease the total crystalloid given during resuscitation.

Reference: The crystalloid / packed red blood cell ratio following massive transfusion: when less is more. Presented at the 24th Annual Scientific Assembly of the Eastern Association for the Surgery of Trauma, January 2011.