{"id":18315,"date":"2026-09-24T00:23:46","date_gmt":"2026-09-23T22:23:46","guid":{"rendered":"https:\/\/www.badania-medyczne.pl\/preoperative-tests-checklist-validity-and-postponement\/"},"modified":"2026-09-24T00:23:46","modified_gmt":"2026-09-23T22:23:46","slug":"preoperative-tests-checklist-validity-and-postponement","status":"publish","type":"post","link":"https:\/\/www.badania-medyczne.pl\/en\/preoperative-tests-checklist-validity-and-postponement\/","title":{"rendered":"Preoperative Tests: Complete Checklist, Result Validity and Reasons for Postponement"},"content":{"rendered":"

Surgical procedures performed under anaesthesia, from tonsil removal to hip replacement, are preceded by laboratory tests. Their purpose is not simply to tick a box, but to assess whether your body can safely tolerate anaesthesia and blood loss, whether there is an undetected infection or blood clotting disorder, and to establish a baseline for postoperative monitoring. The list depends on the type of procedure, your age and any existing medical conditions, but the core investigations are similar. Below, we explain what a standard preoperative test panel includes, why each test matters, how long the results remain valid and how to avoid losing your surgery date because your results have expired. The final list of required tests is always determined by your surgeon or anaesthetist.<\/p>\n

Standard preoperative test panel<\/h2>\n

Full blood count<\/h3>\n

Haemoglobin and haematocrit levels help determine whether a patient has sufficient reserves to tolerate blood loss during surgery. Preoperative anaemia increases the risk of blood transfusions and complications, so it is important to detect and treat it in advance (intravenous iron can take several weeks to produce an effect). The white blood cell count helps identify an ongoing infection, while the platelet count forms part of the assessment of blood clotting.<\/p>\n

Blood group and Rh factor<\/h3>\n

Required before any procedure involving a risk of blood transfusion. Blood grouping must be performed twice using samples collected independently (or confirmed by an official document, such as a blood group identification card). A confirmed blood group result remains valid indefinitely, but the hospital may require its own confirmation.<\/p>\n

Blood clotting: APTT, PT (INR) and fibrinogen<\/h3>\n

These tests help detect inherited and acquired blood clotting disorders and monitor patients taking anticoagulant medicines. INR is particularly important for people taking warfarin or acenocoumarol. Newer anticoagulants (rivaroxaban, apixaban and dabigatran) are not reliably assessed by routine coagulation tests and must be stopped according to a schedule established by your doctor, usually 24\u201372 hours before surgery.<\/p>\n

Electrolytes: sodium and potassium<\/h3>\n

Abnormal Potassium (K) – laboratory test results increase the risk of heart rhythm disturbances during anaesthesia, and correcting potassium levels before surgery is relatively straightforward. Sodium (Na) – laboratory test and potassium measurements are particularly important for people taking diuretics or blood pressure medication and those with kidney disease.<\/p>\n

Creatinine, eGFR and urea<\/h3>\n

Assessment of kidney function, including Creatinine – laboratory test and eGFR, helps determine appropriate doses of anaesthetic medicines, antibiotics, contrast agents and painkillers. Kidney impairment increases the risk of complications and requires adjustments to fluid management.<\/p>\n

Glucose<\/h3>\n

Undiagnosed diabetes or poorly controlled blood glucose can delay wound healing and increase the risk of infection. Glucose – laboratory test is therefore important before surgery. People with diabetes should also have Glycated haemoglobin (HbA1c) measured. Many centres postpone elective procedures when HbA1c exceeds 8\u20138.5%.<\/p>\n

Liver function tests: ALT, AST and bilirubin<\/h3>\n

The liver metabolises anaesthetic medicines and produces blood clotting factors. Elevated Alanine aminotransferase (ALT) – laboratory test, Aspartate aminotransferase (AST) – laboratory test or Total bilirubin – laboratory test results require investigation before surgery, rather than afterwards.<\/p>\n

Viral screening: hepatitis B surface antigen, anti-HCV and HIV<\/h3>\n

These tests are standard in most hospitals and help protect both healthcare staff and patients (procedures may be modified if a result is positive). Anti-HBs testing (antibodies produced following hepatitis B vaccination) helps determine whether a patient is immune to hepatitis B. Many surgeons recommend vaccination before a planned procedure, which requires several weeks.<\/p>\n

Urinalysis<\/h3>\n

Urinalysis helps detect asymptomatic urinary tract infections, which may be a contraindication to implant procedures (joint replacements and hernia meshes), as well as proteinuria and glycosuria.<\/p>\n

Additional tests depending on the procedure and patient<\/h2>\n