All posts by The Trauma Pro

When To Stop The Massive Transfusion Protocol

Initiating the massive transfusion protocol (MTP) is generally easy. Some centers use the Assessment of Blood Consumption score (ABC). This consists of four easy parameters:

  • Heart rate > 120
  • Systolic blood pressure < 90
  • FAST positive
  • Penetrating mechanism

The presence of two or more indicators reliably predicts a 50% chance of needing lots of blood.

The shock index (SI) is also used. It’s more quantitative, just divide the heart rate by the systolic blood pressure. The normal value is < 0.7. As it approaches 0.9, the risk for massive transfusion doubles. This technique requires a little calculation, but is easily doable.

Or you can just let your trauma surgeons decide when to order it. Unfortunately, this sometimes gets forgotten in the mayhem.

However it got started, your MTP is now humming right along. How do you know when to stop? This is much trickier, and unfortunately can’t be as easily quantified. Here are the general principles:

  • All surgical bleeding must be controlled. Hopefully your patient didn’t get too cold or acidotic during the case, resulting in lots of difficult to control nonsurgical bleeding (oozing).
  • Hemodynamics are stabilizing. This doesn’t necessarily mean they are quite normal yet, just trying to approach it.
  • Vasopressors are off, or at least being weaned.
  • Volume status is normalizing. You may need an echo to help with this assessment.

If you have TEG, it probably wasn’t very useful. Until now. This is the ideal time to run a sample so you can top off any specific products your patient might need.

If you don’t have TEG, get a full coag panel including CBC, INR, PTT, lytes with ionized calcium.

Once the patient is in your ICU, continue monitoring and tweaking their overall hemodynamic and coagulation status until they are approaching normal. Then watch out for additional insults or any new and/or unsuspected bleeding. If this does occur, the threshold for return to the OR should be low. Unfortunately it is common for arteries in spasm to resume bleeding after warming and vasodilation.

When you are finally satisfied that there is no more need for the MTP, let your blood bank know so they can start restocking products and getting ready for the next go around!

When To Call Your Urology Consultant

Trauma professionals don’t always know everything. Sometimes we have to engage a specialist in the care of our patient. And unfortunately, we don’t always know which conditions demand immediate attention and which can wait.

This can lead to overuse of our consultant colleagues and calls  at inappropriate times. So what if we diagnose an injury in their area of expertise at 2 am? Does it need attention or an operation before morning? If not, why call at that ungodly hour? Give them a break!

Let’s use our consultants wisely! I’ve listed most of the common urologic diagnoses that trauma professionals will encounter. There is also an indication of what you need to do, and exactly when to call your consultant.

Here’s a reference sheet formatted at a 3×5 index card that you can keep in your pocket. I’ve included a printable pdf file, as well as the original Microsoft Publisher file in case you want to make a few modifications to suit your own hospital.

Enjoy!

When to call Urology reference card (pdf)

When to call Urology MS Publisher file (pub)

Surveillance For Splenic Pseudoaneurysm After Injury

When it comes to repeat CT scanning after splenic injury, there are believers and there are non-believers. In my experience, the majority of centers in the US are non-believers. However, there is a new paper in press that attempts to convince us that more should become believers.

I think the biggest lesson to be learned from this paper is that WE SHOULD READ THE ENTIRE PAPER before drawing conclusions. I have said this in the past and I will say it again. In this case, not only did I read the entire paper, but I had to dig deep into the references it cited as well.

Nonoperative management of splenic injuries has a very high success rate if done properly. Some papers claim this can be up to 93%, which parallels my experience. This success rate involves excluding unstable patients (they need to be in the operating room) and planned use of angioembolization in select patients. Over the years we have found that we need to do less and less in the management of solid organ injury patients:

  • No bedrest
  • No starvation (NPO status)
  • No serial blood draws
  • No repeat CT scan
  • Few limitations on activity after discharge

For an example of a practice guideline that demonstrates that less is more, use the download link at the end of this post.

But back to the question about repeat CT scanning before discharge. Why do we need to do this? The usual reason is that “we want to find delayed pseudoaneurysms.” And why is that important? “It might bleed!”

Really? Let’s look into that through the lens of this new paper by the group at the University of Cincinnati. They performed a retrospective study of their experience with patients who had sustained blunt splenic injury during a recent three-year period. They were interested in how many underwent splenectomy or splenorrhaphy, who had repeat CT imaging, who went to interventional radiology (IR) and when, and which ones were found to have pseudoaneurysms and what was done about it.

Here are the factoids:

  • There were 539 patients who met inclusion criteria, with an average ISS of 24
  • Of these, 46 died during their hospital stay (none from their splenic injury)
  • Focusing on the 248 patients with higher grade injuries (III-V), 125 (50%) underwent emergent or delayed splenectomy. Early vs late operation was not broken out, but this is a startlingly high number!
  • Of the higher grade injured patients who kept their spleens, 97% underwent repeat CT around day 5
  • Delayed pseudoaneurysms were detected in the following patients:
    • Grade III: 10 of 88 patients (11%). Then 8 of those 10 went to IR, and 5  of 10 had splenectomy!
    • Grade IV: 7 of 24 (29%).  Then 8 of the 7 (error in the paper?) went to IR and 3 of 7 had splenectomy!
    • Grade V: 2 of 5 (40%). Both of these patients went to IR and somehow kept their spleens.

The authors conclude that routine followup CT imaging identifies splenic pseudoaneurysms allowing for interventions to minimize delayed complications.

Bottom line: Whoa! There’s a lot going on here. My first observation is that this center does a lot of splenectomies! Of the 539 patients (all comers) who were included in the study, 129 (24%)  lost their spleens. If grade I-II injuries are excluded that percent rises to 50%!

Only eight splenectomies were performed after the repeat CT. This would imply that there were either a lot of unstable patients with splenic injury, the institutional indications for this procedure arbitrarily include grade, or there is a lot of variability in the decision to perform it.

I think there are really two questions to answer here. 

  1. Does delayed splenic pseudoaneurysm occur? The answer is yes. There are a few studies (performed by believers) that demonstrate new pseudoaneurysms after repeat CT. I’m convinced.
  2. Do we care? The real question is, do these pseudoaneurysms cause harm? The fear is that they might explode at some point after patient discharge and cause a major problem.

Papers written by the believers cite a number of old studies and give numbers between 2% and 27% for incidence of delayed hemorrhage. Well, I tracked down all of these papers, including the ones they cited. And it doesn’t add up.

  • One paper from a believer institution found no delayed bleeds.
  • Several papers were for pediatric patients, whose spleens don’t behave like adult ones. They found one case after discharge in one out of 276 patients across three studies.
  • Of 76 adolescents, none encountered delayed bleeds

Many of the papers cited regarding bleeding complications are very old. CT scanners had less resolution, and in many papers, IR was not even a consideration. 

So here’s my take. Yes, delayed pseudoaneurysms occur. In children we don’t care. They almost never cause a problem. But in adults, they can and do cause issues and should be embolized shortly after the initial scan. 

Once embolized, the ones seen on that initial scan are effectively neutralized and do not need a repeat scan. The small ones that might pop up later may very well be part of the healing process. And they may not even occur if angioembolization is done early. It seems unlikely that anything further is needed.

But remember, clinical judgement trumps all. If your patient starts complaining of new abdominal symptoms while in the hospital or after discharge, get a prompt CT scan to rule out any developing complications.

Sample solid organ injury protocol: click here

Reference: Delayed splenic pseudoaneurysm identification with surveillance imaging. J Trauma Acute Care Surg. 2022 Mar 22. doi: 10.1097/TA.0000000000003615. Epub ahead of print. PMID: 35319540.

 

The Role Of Postop CT Scan In Penetrating Trauma

CT scans are commonly used to aid the workup of patients with blunt trauma. They are occasionally useful in penetrating trauma, specifically when penetration into a body cavity is uncertain and the patient has no hard signs that would send him or her immediately to the operating room.

Is there any role in operative penetrating trauma, after the patient has already been to the OR? The dogma has always been that the eyeballs of the surgeon in the OR are better than any other imaging modality. Really? The surgical group at San Francisco General addressed this question by retrospectively reviewing 6 years of their operative penetrating injury registry data. They were interested in finding how many occult injuries (seen with CT but not by the surgeon) were found on a postop CT. A total of 225 patients who underwent operative management of penetrating abdomen or chest injury were included. Here are the factoids:

  • Only 110 patients had a postop CT scan; 73 had scans within the first 24 hours, the other 37 were scanned later
  • Rationale for early scan was to investigate retroperitoneal injury in half of patients, but frequently no indication was given (41%)
  • Rationale for late scan was for workup of ileus in one third, or for evaluation of new or unexpected clinical problems
  • Occult injuries were found in about half of early CT patients (52%), and 22% of late CT patients
  • The most common occult injuries were fractures, GU issues, regraded solid organ injury, and unrecognized vascular injuries
  • Ten patients had management changes, including:
    • Interventional radiology for four injuries with extravasation
    • Operation for orthopedic or GU injury in seven patients
    • One patient underwent surgery for an unstable spine fracture

Bottom line: There appears to be a significant benefit to sending some penetrating injury patients to CT in the early postop period. Specifically, those with injury to the retroperitoneum, deep into the liver, near the spine, or with multiple and complicated injuries would benefit. Simple stabs and gunshots that stay away from these areas/structures probably do not need followup imaging. 

Reference: Routine computed tomography after recent operative exploration for penetrating trauma: What injuries do we miss? J Trauma 83(4):575-578, 2017.

How Early Can We Start Chemoprophylaxis In TBI Patients?

We’ve learned a couple of things in the last two posts by reviewing recent systematic review / meta-analysis studies. First, low molecular weight heparin provides better prophylaxis against venous thromboembolism (VTE) than unfractionated heparin. And giving prophylaxis within the first 72 hours of admission significantly decreases the incidence of VTE with no increase in existing intracranial bleeds or mortality.

So the only remaining question is, how low can you go? That is, how soon can you safely start chemoprophylaxis? The trauma group at George Washington University in DC put together a study to examine this question.

They, and one other Level I trauma center, performed a retrospective cohort study of adult, blunt TBI patients over a three year period. Patients with penetrating brain injury, and those with any other body region with significant injury (AIS >1) were excluded so this group truly represented isolated brain injury. Other exclusion criteria were progression of blood on CT within 6 hours, and crani or death within 24 hours. Early VTE prophylaxis was defined as occurring within 24 hours, and late was > 24 hours.

All patients had hourly neuro evaluations and a repeat head CT at six hours after admission. All had compression devices applied to their legs, and received either low molecular weight (LMWH) or unfractionated heparin (UH) at a fixed dose regarding of body habitus. Anti-Factor Xa levels were not measured.

Here are the factoids:

  • Between the two centers, 264 met inclusion criteria
  • About 40% received early prophylaxis and the remaining ones received their drug after 24 hours
  • ISS was higher (18 vs 15) and GCS was lower (13 vs 14) in the late therapy group
  • About 88% of patients in the early prophylaxis group received LMWH vs only 63% in the late group
  • Average time to prophylaxis start in the early group was 17 hours vs 47 hours in the late group
  • There were no differences in bleed progression between early and late groups (5.6% vs 7%)
  • The craniotomy / craniectomy rates were the same in early and late groups (1.9% vs 2.5%)
  • VTE rate was the same in early vs late groups (0% vs 2.5%)

Bottom line: The authors concluded that there was no additional risk in giving early VTE prophylaxis in TBI patients with a stable CT seven hours after arrival. This was true for patients with subdural, epidural, subarachnoid, and intraparenchymal bleeds.

But there are some limitations to consider. This was a retrospective study, and was a “how we do it” study” as well in terms of the choice of LMWH vs UH. This means there was not protocol for the form of heparin used; that was determined by surgeon preference. 

There was also a difference in ISS and GCS between groups. However, the difference may not have been clinically significant, and it could have made the late group look worse if it were. Statistically, it did not.

And finally, the numbers are small and there was no power analysis. So there is the question of whether a significant difference could have even been detected.

What does it all mean? Well, it suggests that early (within 24 hours) chemoprophylaxis does not cause harm compared to later administration. But the study is not definitive enough to change practice yet. It should definitely prompt discussions and practice guideline development for starting prophylaxis after 24 hours of CT scan stability now. And hopefully these authors (or others) are planning a better prospective study to help us start even sooner!

Reference: Early chemoprophylaxis against venous thromboembolism in patients with traumatic brain injury. Am Surgeon 88(2):187-193, 2021.