Category Archives: Solid organ

Serial Hemoglobin / Hematocrit – Huh? Part 2

May 20, 2020 The Trauma Pro Leave a comment

In my last post, I waxed theoretical. I discussed the potential reasons for measuring serial hemoglobin or hematocrit levels, the limitations due to the rate of change of the values, and conjectured about how often they really should be drawn.

And now, how about something more practical? How about an some actual research? One of the more common situations for ordering serial hemoglobin draws occurs in managing solid organ injury. The vast majority of the practice guidelines I’ve seen call for repeating blood draws about every six hours. The trauma group at the University of Florida in Jacksonville decided to review their experience in patients with liver and spleen injuries. Their hypothesis was that hemodynamic changes would more likely change management than would lab value changes.

They performed a retrospective review of their experience with these patients over a one year period. Patients with higher grade solid organ injury (Grades III, IV, V), either isolated or in combination with other trauma, were included. Patients on anticoagulants or anti-platelet agents, as well as those who were hemodynamically unstable and were immediately operated on, were excluded.

Here are the factoids:

A total of 138 patients were included, and were separated into a group who required an urgent or unplanned intervention (35), and a group who did not (103)
The intervention group had a higher ISS (27 vs 22), and their solid organ injury was about 1.5 grades higher
Initial Hgb levels were the same for the two groups (13 for intervention group vs 12)
The number of blood draws was the same for the two groups (10 vs 9), as was the mean decrease in Hgb (3.7 vs 3.5 gm/dl)
Only the grade of spleen laceration predicted the need for an urgent procedure, not the decrease in Hgb

Bottom line: This is an elegant little study that examined the utility of serial hemoglobin draws on determining more aggressive interventions in solid organ injury patients. First, recognize that this is a single-institution, retrospective study. This just makes it a bit harder to get good results. But the authors took the time to do a power analysis, to ensure enough patients were enrolled so they could detect a 20% difference in their outcomes (intervention vs no intervention).

Basically, they found that everyone’s Hgb started out about the same and drifted downwards to the same degree. But the group that required intervention was defined by the severity of the solid organ injury, not by any change in Hgb.

I’ve been preaching this concept for more than 20 years. I remember hovering over a patient with a high-grade spleen injury in whom I had just sent off the requisite q6 hour Hgb as he became hemodynamically unstable. Once I finished the laparotomy, I had a chance to pull up that result: 11gm/dl!

Humans bleed whole blood. It takes a finite amount of time to pull fluid out of the interstitium to “refill the tank” and dilute out the Hgb value. For this reason, hemodynamics will always trump hemoglobin levels for making decisions regarding further intervention. So why get them?

Have a look at the Regions Hospital solid organ injury protocol using the link below. It has not included serial hemoglobin levels for 18 years, which was when it was written. Take care to look at the little NO box on the left side of the page.

I’d love to hear from any of you who have also abandoned this little remnant of the past. Unfortunately, I think you are in the minority!

Click here for the Regions Hospital Solid Organ Injury Protocol

Reference: Serial hemoglobin monitoring in adult patients with blunt solid organ injury: less is more. J Trauma Acute Care Open 5:3000446, 2020.

Update: Kidney Injury Scaling

February 27, 2019 The Trauma Pro Leave a comment

Over the past two days, I’ve reviewed the new AAST organ injury scaling updates for spleen and liver injuries. Today, I’ll cover the new kidney grading scale.

Liver and spleen grading is generally simple, focusing on laceration depth and subcapsular hematoma coverage to determine the exact value. However, the kidney is totally different. Although technically a solid organ, it’s got a bunch of hollow, urine-containing stuff inside. This is the main determinant of the original scaling system: collection system involvement.

Like liver and spleen, the kidney scale was updated to take advantage of CT information. But once again, bleeding identified via the CT angiogram is incorporated into the higher grades. Active bleeding contained within Gerota’s fascia is assigned a grade of III. Extravasation escaping this fascia is assigned a IV. The other grades remain unchanged.

Here are the updated guidelines. Click the image or link below it to open a bigger image in a new window.

Click to download larger image

Links:

Updated AAST spleen scaling system
Updated AAST liver scaling system
Updated AAST kidney scaling system

Solid organ

Update: Liver Injury Scaling

February 26, 2019 The Trauma Pro Leave a comment

In my last post, I reviewed the updated AAST organ injury scaling (OIS) for the spleen. Today, I’ll share details of the new version of liver grading.

First, the overall focus of the updated liver scale is similar to the spleen one: it incorporates a listing of criteria identified by CT scan that parallels the old anatomic criteria. The CT column contains all the old anatomic stuff, but now includes scaling for active bleeding.

The confusing part? Whereas contained active bleeding within the spleen was Grade IV and active bleeding escaping the spleen was Grade V in the updated scale, these drop down a grade in the liver. So bleeding contained with the liver parenchyma is Grade III and active extravasation escaping into the peritoneal cavity is only Grade IV. I presume this has to do with the abbreviated injury score (AIS) used to calculate ISS, and that the mortality hit from this degree of bleeding is less than that of the spleen.

The final difference between the updated scale and the original is the removal of Grade VI. This was previously described as hepatic avulsion, which is a nonsurvivable injury. The AIS for Grade VI liver used to be 6, which causes an immediate ISS calculation short circuit to 75. Which also means that survival is approximately 0%. This is not part of the OIS update, which may be due to the fact that it never occurs in anyone who makes it to a trauma center alive.

Here are the updated guidelines. Click the image or link below it to open a bigger image in a new window.

Click to download larger image

In the next post, I’ll review the new features of the kidney injury scale.

Solid organ

Update: Spleen Injury Scaling

February 25, 2019 The Trauma Pro Leave a comment

Over the years, the American Association for the Surgery of Trauma (AAST) has developed and maintained a library of organ injury scales. Organ injury scaling allows us to compare apples to apples in research studies, and in many cases enables us to tailor interventions and predict outcomes. Many of the scales have been in place for decades and have not been updated. The spleen, liver, and kidney scales were introduced 25 year ago, and received their first update last December. During the next three posts, I’ll review what’s new and different with them.

The biggest change to all three scales has been the incorporation of specific vascular injuries seen on modern-day CT scans. It is recommended that scanning for solid organ injury be conducted using dual phase (arterial and portal venous) scanning techniques. This increases study sensitivity and provides the best images for accurate diagnosis and scaling. Also note that specific criteria are now provided for CT, intraoperative, and pathologic diagnosis.

Let’s start with the spleen today. Here are the updated guidelines. Click the image or link to get a bigger image in a new window.

Click to download larger image

The main change to this scale is the addition of active bleeding contained within the spleen (pseudo-aneurysm or contained extravasation) to Grade IV, and uncontained extravasation to Grade V.

In my next post, I’ll discuss the new features of the liver injury scale.

Solid organ

APSA Activity Restrictions After Solid Organ Injury: Aren’t We Done With That Yet?

November 1, 2018 The Trauma Pro Leave a comment

Nearly 20 years ago, the American Pediatric Surgical Association (APSA) published a clinical guideline for management of solid organ injury in children. Part of the guideline included activity restrictions, specifically for a period of time after injury. This was generalized by many clinicians to include a period of in-hospital bed rest.

A paper has just been published that examines the usefulness of restricting activity in pediatric patients with solid organ injury. It was authored by a consortium of 10 Level I pediatric trauma centers, and included all patients through age 18 who did not have a concomitant significant renal injury and no pancreatic injury. All injuries were diagnosed by CT scan over a 33 month period.

Activity restrictions were given to all patients upon discharge, which limited sports, wheeled recreational activities, and anything else requiring two feet off the ground. A phone survey was conducted 60 days post-discharge to judge compliance. Unplanned return to ED, readmission, and complications were also assessed.

Here are the factoids:

A total of 1007 patients were studied, and 99 were excluded due to concomitant pancreatic or high grade renal injury. An additional 79 were excluded due to missing injury grade or operative management.
Of the remaining patients, only 366 were available for 60-day followup
279 claimed to adhere to activity restrictions; 13% returned to the ED and 6% were readmitted.
49 admitted that they did not pay attention to the restrictions, and only 4 (8%) returned to the ED. None were hospitalized.
Even in the high-grade injury patients, there was no difference between compliant or noncompliant groups
No patient in either group bled post-discharge

Bottom line: Due to the nature of this study (specifically the phone survey component), there will be degradation of the data. Some patients do not want to admit that they didn’t follow the doctor’s orders. In theory, this could increase the number of complications / returns to ED in the “compliant” group. But it did not.

The other issue I have with this study is that it was not stratified by age. The spleen of an 18 year old is very different than that of a 6 year old. Sixty years ago, we used to take spleens out in adults with a diagnosed injury. The reason we moved toward nonoperative management in adults was the very favorable experience we had in children. Unfortunately, nowhere in this paper is age broken out. Typically, the number of older children (who are really adults) with the injury far outnumber the younger ones, which also tends to increase the number of complications seen. But once again, we did not. Small numbers? Possibly.

So what are we to make of all this? Basically, it tells us that we’ve been trying to restrict activity in our patients with liver and spleen injury for no good reason. And this applies especially to the children. Look at your own clinical experience, and try to recount how many “failures” you’ve seen due to failure to follow activity restrictions. More typically, failures are due to undiagnosed or untreated pseudoaneurysms.

It’s time to rethink your solid organ management protocol, if you haven’t already. Do you really need a period of NPO status? Or bedrest? Or activity restriction? And have you ever tried to restrict activity in a 6-year old? Have a look at the guideline we’ve used at my hospital for nearly 20 years! We got rid of the NPO and bedrest restrictions a while ago. Now it’s time to start reducing the activity restrictions!

References:

Evidence-Based Guidelines for Resource Utilization in Children With
Isolated Spleen or Liver Injury. J Ped Surg 35(2):164-169, 2000.
Adherence to APSA activity restriction guidelines and 60-day clinical outcomes for pediatric blunt liver and splenic injuries (BLSI). J Ped Surg in Press, 2018.

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