Acquired Bleeding Disorders

1. THE 2-MINUTE PHYSIOLOGY (Rapid Pathophysiology)

Acquired bleeding disorders and massive hemorrhage lead to a profound breakdown in normal hemostatic mechanisms, driving a rapid progression toward hypovolemic shock and cellular hypoxia. In severe trauma or massive hemorrhage, the loss of blood volume severely compromises oxygenation, ventilation, and end-organ perfusion. This state is often exacerbated by iatrogenic or intrinsic coagulopathies, such as the use of NSAIDs or anticoagulants, which irreversibly alter platelet function and the coagulation cascade. Furthermore, massive resuscitation efforts can dilute circulating clotting factors and fibrinogen, while citrate in stored blood products binds serum calcium, triggering dangerous hypocalcemia that further impairs the coagulation cascade and cardiac contractility.

2. THE BEDSIDE ACTION PLAN (Rapid ER Management)

• The xABCDE Approach: You must prioritize x (Control of eXsanguinating Hemorrhage) before moving to Airway. Apply direct pressure and immediately evaluate the indications for extremity tourniquet application.
• Massive Hemorrhage Protocol (MHP): Activate MHP early. Transfuse blood products in a balanced ratio: 6 units PRBCs : 6 units FFP : 1 Plateletpheresis Pack.
• Calcium Repletion: Administer 1g of Calcium with the first unit of blood, followed by an additional 1g for every 4 units of PRBCs administered.
• Tranexamic Acid (TXA):
• Trauma: Administer 2g slow IV push early (ideally within 60 to 90 minutes of injury).
• Postpartum Hemorrhage (PPH): Administer 1g, then repeat.
• GI Bleeding: Avoid TXA, as it is associated with harm in this specific population.
• Resuscitation Targets: Monitor serial labs to maintain the following goals: Hb > 7 g/dL, INR < 1.8, Platelets > 50 (or > 100 in intracranial hemorrhage), Fibrinogen > 1.5–2 g/L, and ionized calcium > 1-1.2 mmol/L.

3. THE DIAGNOSTIC GRID (Differential Diagnosis & Workup)

• Critical "Can't-Miss" Differential Diagnoses:
• Hemorrhagic shock secondary to trauma (e.g., solid organ injury, pelvic fracture).
• Ruptured abdominal aortic aneurysm (AAA) or aortic dissection.
• Ruptured ectopic pregnancy.
• Severe gastrointestinal bleeding (e.g., variceal rupture in cirrhosis, peptic ulcer disease).
• Disseminated Intravascular Coagulation (DIC).
• Prioritized Diagnostic Workup:
• Immediate Labs: Type and cross-match (request 4–6 units of type-specific blood immediately if urgent), complete blood count (FBC), comprehensive metabolic panel (U&E), glucose, and full coagulation studies (PT/INR, PTT).
• Perfusion Markers: Obtain a serial lactate and arterial blood gas (ABG) to assess metabolic acidosis and perfusion.
• (Note: Outside of your sources, additional critical labs for acquired bleeding include Thromboelastography (TEG) or Rotational Thromboelastometry (ROTEM) to dynamically guide factor replacement).

4. THE VISUAL BOARD (ECG / POCUS / Imaging)

• Point-of-Care Ultrasound (POCUS) / eFAST:
• Immediately perform an eFAST or Rapid Ultrasound for Shock and Hypotension (RUSH) exam.
• Look specifically for free fluid (hemoperitoneum) in Morrison's pouch, the splenorenal recess, and the pelvis.
• Assess for hemopericardium, hemothorax, and dynamically evaluate the inferior vena cava (IVC) diameter and collapse to estimate volume status and central venous pressure.
• ECG: Perform an ECG on any patient over 50 years old to evaluate for demand ischemia or concomitant acute coronary syndrome triggered by profound hypovolemia.
• Advanced Imaging: If the patient is stable enough, obtain emergent CT-angiography to evaluate for retroperitoneal hemorrhage or ruptured AAA.

5. THE SCORING MATRIX (Risk Stratification & Guidelines)

• GI Bleed Risk Factors: The risk of further bleeding and mortality increases significantly with advanced age, existing comorbidities, hemodynamic instability, and the use of NSAIDs or aspirin.
• Disposition Criteria: You may only consider discharging a bleeding patient if they are young, otherwise healthy, have passed only a very small amount of blood, have completely normal vital signs, and do not take NSAIDs or anticoagulants. Always arrange strict follow-up for these patients.

6. THE DANGER ZONE (Pitfalls & Critical Actions)

• Deadly Pitfall (TXA): Administering Tranexamic Acid (TXA) to a patient with acute gastrointestinal bleeding. The sources explicitly note that TXA in GI bleeding can cause patient harm and should be avoided.
• Deadly Pitfall (Calcium): Failing to administer calcium during massive transfusion. Citrate toxicity from PRBCs will rapidly induce hypocalcemia, worsening coagulopathy and causing cardiovascular collapse.
• Critical Action: Executing the "xABCDE" paradigm. Examiners will fail candidates who intubate (Airway) before placing a tourniquet on a compressible, exsanguinating arterial extremity bleed (x).

7. MCQ MASTERCLASS (Written Exam Tips)

• Buzzword: "1:1:1 ratio" or "6:6:1" – This refers to the optimal massive hemorrhage protocol ratio of 6 units of PRBCs, 6 units of FFP, and 1 Plateletpheresis pack.
• Distractor: A question may offer TXA as a treatment option for a crashing patient with a massive upper GI bleed. You must recognize this as a distractor and avoid it.
• Key Cutoffs: Memorize the trauma lab resuscitation thresholds: Keep Fibrinogen > 1.5–2, INR < 1.8, and Platelets > 50 (or >100 if the patient has an intracranial hemorrhage).

8. THE BOARDROOM SCRIPT (OSCE & Oral Board Tips)

• Initial Action: "I will begin with the xABCDE approach. My immediate priority is to identify any life-threatening compressible external hemorrhage and apply a tourniquet or direct pressure before assessing the airway."
• Resuscitation: "Given the hemodynamic instability, I am activating the Massive Hemorrhage Protocol. I want uncrossmatched O-negative blood brought to the room. We will transfuse PRBCs, FFP, and platelets in a 6:6:1 ratio. Nurse, please administer 1 gram of IV Calcium now, and prepare 2 grams of IV Tranexamic Acid over 10 minutes."
• Diagnostic Action: "I am bringing the ultrasound machine to the bedside to perform an immediate eFAST exam, specifically looking for hemoperitoneum, hemothorax, or hemopericardium to find the source of this patient's shock."
• Consultation: "This patient has free fluid in the abdomen on ultrasound and remains in hemorrhagic shock. I need an emergent general surgery consult to the bedside for operative intervention, as we continue damage control resuscitation."