This week in Morning Report, we discussed two cases of patients from very different age categories, who presented with symptoms suggestive of a bleeding diathesis — easy bruising and unexpected non-traumatic bleeding. We used these cases to discuss an practical approach to the patient with easy bruising and bleeding.
If bleeding disorders set your heart racing and make your brain feel scrambled, you’re not alone — most people (except those destined for hematology from the womb!) would find this intimidating:
The good news? You definitely don’t need to understand any of this in order to investigate bruising and bleeding. Let’s break it down step by step.
1. Understand some basics about hemostasis
I like to think of hemostasis as a recipe, with the final product being a stable clot or controlled bleeding. I ask myself the same few questions for every bruised/bleeding patient:
- What are the key steps in hemostasis? In each step, what can go wrong? This helps you narrow the ‘localization’ of the problem.
- Is the problem inherited or acquired? The age of onset and timecourse can help you figure this out.
Let’s understand some basic elements of hemostasis, which are nicely demonstrated in the figure below (note – this is a dramatic oversimplification, but is a sufficient starting point for understanding!):
- Primary Hemostasis: This is your ‘first on the scene’ response. The goal of primary hemostasis is to form a platelet plug to try and stop bleeding. When an endothelial wall is injured, endothelin is released and causes immediate vasoconstriction. Platelets rush to the scene of the exposed endothelium, where, with the help of Von Willebrand Factor (VWF), they can bind to the endothelium. Fibrinogen helps bridge platelets together to form a plug. Therefore, the key ingredients in primary hemostasis are: platelets, VWF, fibrinogen, and an endothelial wall.
- Secondary Hemostasis: This is the more sophisticated ground crew. The goal of secondary hemostasis is to create a stable fibrin clot to stop bleeding. This is where the coagulation cascade (remember your intrinsic and extrinsic pathways!) are activated with the ultimate goal of creating a fibrin plug. The key ingredients in secondary hemostasis are: clotting factors and fibrinogen.
- A few clotting cascade mnemonics may be helpful to you:
- Extrinsic Pathway = PT (Play Tennis OUTSIDE/EXTRINSIC), Intrinsic Pathway = PTT (Play Table Tennis INSIDE/INTRINSIC)
- Intrinsic Pathway is Factors 8-9-11-12, Extrinsic Pathway is 7, and Common Pathway is 2-5-10 (denominations of Canadian currency)
- Factor 4 is actually CALCIUM! This is why massive hemorrhage protocols and trauma protocols are so fixated on mitigating hypocalcemia — it worsens coagulopathy!
- A few clotting cascade mnemonics may be helpful to you:
2. Remember a few pearls and resources for your bleeding history
I cannot emphasize enough how much history-taking matters when dealing with a bleeding and bruising! The age of onset, family history, and pattern of bleeding are key things to elucidate.
Most importantly, a standardized validated bleeding questionnaire is extremely important to administer in the office setting. These have a sensitivity/specificity of 85-100% depending on the test, and take only 10-15 minutes for the patient or clinician to do in the office setting. A negative validated bleeding questionnaire eliminates the need for further testing. This link contains information on several validated bleeding questionnaires including the most commonly used MCMDM-1, Self-BAT, and ISTH-BAT.
- Age of Onset: Many congenital bleeding disorders will be discovered in childhood with symptoms of easy bruising or sinister bleeding. However, other inherited bleeding disorders may only manifest much later — e.g., patients first noticing bleeding problems once they start menstruating. In a much older patient with sudden unexplained bleeding or bruising, have a high index of suspicion for inflammatory, autoimmune, or medication-related causes of bleeding.
- Family History: Many bleeding disorders (Von Willebrand’s Disease, Hemophilia A and B, to name a few) have a genetic predisposition with different inheritance patterns. A thorough family history here is invaluable.
- Pattern of Bleeding: This is hugely important to elucidate as the pattern of bleeding varies significantly for primary vs. secondary hemostatic problems! This is shown nicely in the table below.
3. Generate a differential diagnosis based on your ‘hemostatic ingredients’
We went over a differential diagnosis based on which part of the hemostatic pathway was affected. I have summarized this for you in the table below (not a comprehensive list of diagnoses, but just one way to slice this pizza!):
This article from the AAFP has a fantastic table containing clinical clues that may help you elucidate the etiology of new onset bleeding/bruising:
4. A few high-yield resources
The following lists a few great resources to further brush up on your bleeding/bruising/coagulation knowledge:
- Transfusion Ontario’s Bloody Easy: Coagulation Simplified: I have a copy of this saved on my phone and refer to it all the time! Covers all things coagulation, bleeding disorders, evaluating abnormal coagulation tests, emergency management of bleeding, etc.
- AAFP’s Clinical Evaluation of Bleeding and Bruising in Primary Care
- A list of validated bleeding questionnaires
- EM Cases Podcast on the ‘7 Ts of Massive Hemorrhage Protocols’ – even if you’re not an ER, ICU, or Trauma doc, understanding the essentials of Massive Hemorrhage protocols (formerly Massive Transfusion Protocols) is always a good idea, and this episode is just a great listen.
I hope you found this Morning Report useful – as always, any questions/comments are welcome to firstname.lastname@example.org.