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Date: December 16th, 2022

Reference: Hohle et al. Massive Blood Transfusion Following Older Adult Trauma: the Effect of Blood Ratios on Mortality. AEM December 2022

Guest Skeptic: Dr. Kirsty Challen is a Consultant in Emergency Medicine at Lancashire Teaching Hospitals. She is also the wonderful educator that creates the Paper in a Pic infographics summarizing each SGEM episode.

Case: A 71-year-old man is brought to your emergency department (ED) by emergency medical serviced (EMS) having fallen two steps at home. EMS have already splinted an obvious mid-shaft femoral fracture, but he continues to be tachycardic and hypotensive. After a bedside ultrasound shows fluid in the right hemithorax, you insert an intercostal drain which immediately fills with one litre of blood. Noting with some relief that at least he isn’t anticoagulated, you activate the hospital massive transfusion protocol. The transfusion tech calls to remind you that your protocol is currently under review, and asks if would you like the 1:1 or the 1:3 version of fresh-frozen plasma (FFP) to packed red blood cells (pRBC)?

Background: Major trauma in older patients is increasing in frequency (1), with the median age of major trauma patients in the UK from 2012-2017 being 63.6 years (2). Falling is the most common cause of traumatic injury resulting in older adults presenting to the ED [4]. Approximately 20% of falls result in injuries, and falls are the leading cause of traumatic mortality in this age group [5,6,7].

Over the last few years there has been increasing concern that the practice of transfusing only PRBC might worsen traumatic coagulopathy. Although a number of trials have attempted to find optimal ratios for transfusion components and the Eastern Association for the Surgery of Trauma practice guidelines suggest a “high” ratio, little of the literature has addressed how this might be applied in an older population.

We looked at the PROPPR trial on SGEM#109 when it came out in 2015 and concluded then that a 1:1:1 transfusion strategy was a reasonable approach to massive transfusion and that it seemed to achieve more hemostasis and less death from exsanguination at 24 hours.

We’ve also looked at trauma in older patients in SGEM#324 (we don’t yet want to use spirometry to aid discharge decisions in patients with rib fractures), SGEM#212 (increasing age, more rib fractures, more underlying disease and poor oxygenation are risk factors for poor outcome in older patients with chest trauma) and in SGEM#89 in 2014 when we first concluded that identifying older patients at risk of falls is really tricky.

CLINICAL QUESTION: DOES FFP:PRBC RATIO IN MASSIVE TRANSFUSION FOR TRAUMA AFFECT SURVIVAL IN OLDER ADULTS?

Reference: Hohle et al. Massive Blood Transfusion Following Older Adult Trauma: the Effect of Blood Ratios on Mortality. AEM December 2022

  • Population: Patients aged 65 or older receiving massive blood transfusion from American College of Surgeons Trauma Quality Improvement Programme National Trauma Data Bank 2013-2017. Massive transfusion was defined as >=10 units of pRBCs in 24 hours or >=5 units within 4 hours of ED admission.
    • Excluded: Patients who were dead on arrival at ED, patients who received no plasma, and those who received more plasma than red cells.
  • Intervention: 1:1 ratio of FFP to pRBC
  • Comparison: 1:2 or lower ratio of FFP to pRBC
  • Outcomes:
    • Primary Outcome(s): 24-hour and 30-day mortality
    • Secondary Outcomes: Hospital and ICU length of stay, ventilator days, complications and need for emergency surgery for haemorrhage control.
  • Type of Study: Observational cohort study

Dr. Rae Hohle

This is an SGEM HOP and we are pleased to have the lead author on the show. Dr. Rae Hohle is a PGY1 in Emergency Medicine at Regions Hospital in St. Paul, MN. She has a background in computer science and with the support of her program has been able to continue to work on research projects in residency.

Authors’ Conclusions: “Compared to all other ratios, the 1:1 FFP:pRBC ratio had the lowest 24-hour and 30-day mortality following older adult trauma consistent with findings in the younger adult population.”

Quality Checklist for Observational Cohort Studies:

  1. Did the study address a clearly focused issue? Yes
  2. Did the authors use an appropriate method to answer their question? Yes
  3. Was the cohort recruited in an acceptable way? Unsure
  4. Was the exposure accurately measured to minimize bias? Yes
  5. Was the outcome accurately measured to minimize bias? Yes
  6. Have the authors identified all-important confounding factors? Unsure
  7. Was the follow up of subjects complete enough? Yes
  8. How precise are the results? Confidence intervals are relatively broad, from 1.25-2.06 for the largest comparator group.
  9. Do you believe the results? Yes
  10. Can the results be applied to the local population? Yes
  11. Do the results of this study fit with other available evidence? Yes
  12. Funding/Conflicts of Interest? None

Results: In this cohort of over 3,000 patients the odds of mortality increased in line with the transfusion ratio. The mean age was 73 years, 65% were male and 66% had at least one comorbidity. The most common comorbidities were hypertension (39%), diabetes mellitus (16%) and bleeding disorder (11%).

KEY RESULT: A 1:1 RATIO OF PACKED RED BLOOD CELLS AND FFP IS ASSOCIATED WITH SIGNFICANTLY LOWER 24-HOUR AND 30-DAY MORTALITY THAN ANY OTHER TRANSFUSION RATIO

Results from multivariable regression model for covariates independently associated with 24-h and 30-day mortality for the older adult population.

Listen to the SGEM podcast to hear Rae respond to our five nerdy questions.

  1. Information Source – You got your information from the ACS TQIP national trauma database. This might not be familiar to all our listeners – can you tell us a bit more about it? Does it include all trauma centres of all levels and how reliable can its data be?
  2. Survivor Bias – It’s possible that some patients who died early didn’t get a 1:1 ratio because they didn’t have time to get the FFP before they died. Were you able to explore that at all and do you think it might have an impact on your results?
  3. Clustering – 1:1 transfusion might be a marker for other unmeasured quality factors. You have analysed by level of trauma centre but as we can see transfusion ratios varied across all levels. Did you consider analysing whether transfusion ratios were clustered by centre?
  4. Missing Variables – Obviously you can only analyse variables that are collected in the database. We’ve mentioned that we would like to have seen a measure of frailty – was there anything else you would have liked to see?
  5. Other Therapeutic Interventions – It’s interesting to see in Table 3 that as transfusion ratios increased the rate of surgery for hemorrhage control fell. Obviously, this is only hypothesising but did you get a feel for how those were related?

Comment on Authors’ Conclusion Compared to SGEM Conclusion: We agree with the authors’ conclusions.

SGEM BOTTOM LINE: 1:1 TRANSFUSION OF PACKED RED BLOOD CELLS WITH FRESH FROZEN PLASMA IS ASSOCIATED WITH LOWER ODDS OF MORTALITY THAN OTHER TRANSFUSION RATIOS.

Case Resolution: You ask the transfusion tech to send pRBCs and FFP in a 1:1 ratio.

Dr. Kirsty Challen

Clinical Application: I will be taking this information back to my home institution to review and discuss ourMassive Transfusion Protocol ratio of 1:1 for pRBC and FFS in older adults.

What Do I Tell the Patient? You seem to be bleeding from your chest as well as your broken leg. We need to transfuse some blood to replace the blood you’ve lost. We will transfuse two important parts of blood in equal quantities.

Keener Kontest: Last weeks’ winner was Dave Michaelson, a PA and repeat winner. He knew the name for the scaphoid is the navicular and it came from the Latin term for boat. It is now reserved for the tarsal bone. Scaphoid is the Greek term for boat.

Listen to the SGEM podcast for this weeks’ question. If you know, then send an email to thesgem@gmail.com with “keener” in the subject line. The first correct answer will receive a cool skeptical prize.

SGEMHOP: Now it is your turn SGEMers. What do you think of this episode on massive transfusion protocol for older adults? Tweet your comments using #SGEMHOP.  What questions do you have for Rae and her team Ask them on the SGEM blog? The best social media feedback will be published in AEM.

REMEMBER TO BE SKEPTICAL OF ANYTHING YOU LEARN, EVEN IF YOU HEARD IT ON THE SKEPTICS’ GUIDE TO EMERGENCY MEDICINE.

 References:

  1. Jiang, L., Zheng, Z. & Zhang, M. The incidence of geriatric trauma is increasing and comparison of different scoring tools for the prediction of in-hospital mortality in geriatric trauma patients. World J Emerg Surg 15, 59 (2020). https://doi.org/10.1186/s13017-020-00340-1
  2. Dixon JR, Lecky F, Bouamra O, Dixon P, Wilson F, Edwards A, Eardley W. Age and the distribution of major injury across a national trauma system. Age Ageing. 2020 Feb 27;49(2):218-226. doi: 10.1093/ageing/afz151. PMID: 31763677; PMCID: PMC7047820.
  3. Albert A, McCaig LF, Ashman JJ. Emergency department visits by persons aged 65 and over: United States, 2009–2010. NCHS Data Brief 2013;130:1–8.
  4. Masud T, Morris RO. Epidemiology of falls. Age Ageing 2001;30:3–7.
  5. Yildiz M, Bozdemir MN, Kilicaslan I, et al. Elderly trauma: the two years experience of a university-affiliated emergency department. Eur Rev Med Pharmacol Sci 2012;16(Suppl 1):62–7.
  6. Centers for Disease Control and Prevention. Fatalities and injuries from falls among older adults–United States, 1993–2003 and 2001–2005. MMWR Morb Mortal Wkly Rep 2006;55:1221–4.