Blunt Abdominal Trauma with a Normal FAST
A 32-year-old motorcyclist is brought in after a high-speed collision. He is alert but anxious. Primary survey: airway patent, RR 26, SpO2 95% on 15 L, HR 128, BP 92/60, GCS 15, temperature 36.0 C. He has a tender left upper quadrant and a seat-belt sign. FAST shows no free fluid in the pericardial, perihepatic, perisplenic, or pelvic views. Chest X-ray shows no pneumothorax. Pelvis X-ray is normal. He has received 1 L crystalloid and remains tachycardic. He is on no anticoagulants. The trauma team is debating whether to go to CT or to the operating theatre.
1. How do you interpret the negative FAST and what are your next steps?
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A negative FAST does not exclude significant injury. It is operator-dependent, can miss retroperitoneal, hollow viscus, and diaphragm injuries, and can be falsely negative early or with contained haematoma. This patient is tachycardic and hypotensive after 1 L crystalloid, with a seat-belt sign and LUQ tenderness, so he is at high risk for solid organ or hollow viscus injury. The priority is to determine whether he is a transient or non-responder to resuscitation. If he responds and remains stable, CT with intravenous contrast is appropriate and should include delayed phases for renal and urinary tract assessment. If he remains haemodynamically abnormal, he should go to theatre for laparotomy rather than to the CT scanner. Activate the massive transfusion protocol early if needed, give tranexamic acid within 3 hours, keep him warm, and reassess after each bolus. Involve the consultant surgeon and anaesthetist.
2. CT shows a grade IV splenic laceration with active contrast extravasation and a small amount of free fluid. He remains tachycardic at 120 with BP 100/65 after 2 units of blood. What are the options and how do you choose?
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Options are operative splenectomy, operative splenic salvage, or angioembolisation. Choosing depends on physiology, injury grade, and available resources. Active extravasation with ongoing transfusion requirement suggests ongoing bleeding. In a haemodynamically borderline patient, angioembolisation can be effective if the patient is stable enough to transfer and the service is immediately available. If he deteriorates, laparotomy is required. Splenic salvage by packing or repair is possible in selected cases but carries rebleeding risk. Consider the patient's age and the lifelong risk of overwhelming post-splenectomy infection, which favours salvage when safe, but not at the cost of uncontrolled haemorrhage. Decide with the consultant and interventional radiology, and document the reasoning. If splenectomy is performed, vaccinate against encapsulated organisms and give prophylaxis as per protocol.
3. Two days later he develops abdominal pain, fever, and rising white cell count. What is your differential and how do you investigate?
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Consider missed hollow viscus injury, pancreatic injury, splenic infarction or abscess, infected haematoma, and abdominal compartment syndrome. Examine for peritonism, distension, and wound problems. Check lactate, lipase, blood gas, and coagulation. CT with contrast is the main investigation, looking for free gas, collections, pancreatic fluid, and bowel wall changes. If there is peritonitis or free gas, proceed to laparotomy. If there is a collection, consider percutaneous drainage. Reassess the original imaging for subtle signs. Involve seniors and document the evolving plan.