Returning from Spain with new epigastric pain, in shock

Which initial blood tests are important in this case? (Select all that apply)

The initial VBG shows a Haemoglobin (Hb) of 83 (on review of previous blood tests there was no history of anaemia) and a lactate of 1.7. The patient’s BP transiently improves after a bolus of fluid. A Point of Care Ultrasound (POCUS) is performed, which shows some free fluid in the subcostal views, though is partly limited by bowel gas and body habitus.

What are your top 3 differential diagnoses? (Select all that apply)

The observations remain stable with ongoing hypotension despite Intravenous (IV) fluids. Given the clinical concern, a cross-matched blood transfusion is started, and tranexamic acid is administered. Pain is well controlled with IV morphine and paracetamol.

What are the 2 most important next steps in managing this patient? (Select all that apply)