What are the key investigations to determine the cause of upper GI bleeding in a primary care setting?

In a primary care setting, the key investigations to determine the cause of upper gastrointestinal bleeding include:

• Clinical assessment and risk stratification: Use formal risk assessment tools such as the Blatchford score at first assessment to evaluate the severity and need for urgent referral or intervention ¹.
• Full blood count (FBC): To assess for anaemia and platelet count, which can indicate bleeding severity and guide further management ¹,².
• Coagulation profile: Including prothrombin time and international normalised ratio (INR), especially if the patient is on anticoagulants, to assess bleeding risk and guide reversal if necessary ¹.
• Referral for upper gastrointestinal endoscopy: This is the definitive investigation to identify the source of bleeding and should be arranged urgently or non-urgently depending on clinical stability and risk factors. In primary care, patients with haematemesis or other high-risk features should be referred for direct access endoscopy ¹,².
• Additional tests: In some cases, consider testing for Helicobacter pylori infection if peptic ulcer disease is suspected, although this is usually done after specialist referral ¹.

Primary care's role is mainly initial assessment, risk stratification, and urgent referral for endoscopy rather than performing invasive investigations directly ¹,².