Management of Pre-operative Patient with INR 2.0 and PT 20.8 Seconds Not Taking Warfarin
This patient requires immediate investigation for an underlying coagulopathy or liver disease, as an INR of 2.0 without warfarin indicates a pathologic condition that must be identified and corrected before proceeding with elective surgery.
Immediate Diagnostic Workup
Obtain comprehensive coagulation studies including PT/INR, aPTT, fibrinogen, platelet count, and liver function tests (AST, ALT, bilirubin, albumin) to differentiate between liver disease, vitamin K deficiency, or other coagulopathies 1
Assess for vitamin K deficiency by evaluating for malnutrition, malabsorption syndromes, prolonged antibiotic use, or recent diarrheal illness that could deplete vitamin K stores 2
Review all medications including over-the-counter drugs, herbal supplements, and antibiotics that might interfere with vitamin K metabolism or synthesis of clotting factors 2
Evaluate for occult liver disease including cirrhosis, acute hepatitis, or hepatic synthetic dysfunction, as the liver produces vitamin K-dependent clotting factors (II, VII, IX, X) 3
Pre-operative Correction Strategy
For Vitamin K Deficiency (Normal Liver Function)
Administer vitamin K 5-10 mg orally and recheck INR in 24 hours; this should normalize the INR to ≤1.5 if the underlying cause is vitamin K deficiency 1, 4
Oral vitamin K achieves predictable effectiveness with 95% of patients showing INR reduction within 24 hours, making it the preferred route for non-emergency correction 5
For Liver Disease or Urgent Surgery
If surgery cannot be delayed and INR remains >1.5, administer 4-factor prothrombin complex concentrate (PCC) 25 U/kg IV plus vitamin K 5-10 mg by slow IV infusion to achieve rapid correction to INR <1.5 1, 5
Fresh frozen plasma (FFP) is an alternative if PCC is unavailable, though it requires larger volumes and takes hours versus 5-15 minutes for PCC to achieve correction 5, 6
Critical Decision Points
Proceed with Surgery If:
INR normalizes to ≤1.5 after vitamin K administration and the underlying cause is identified as reversible vitamin K deficiency 4
Liver function tests are normal and there is no evidence of ongoing coagulopathy or bleeding risk 1
Delay Surgery If:
INR remains elevated despite vitamin K administration, suggesting severe liver disease or other irreversible coagulopathy 3
Active bleeding or high bleeding risk is present with uncontrolled coagulopathy 6
The underlying cause remains unidentified, as proceeding without understanding the etiology places the patient at unacceptable risk 7
Common Pitfalls to Avoid
Do not assume the INR is a laboratory error—an INR of 2.0 without anticoagulant therapy always represents a pathologic condition requiring investigation 3
Avoid proceeding with surgery without correction, as even an INR of 2.0 significantly increases surgical bleeding risk compared to normal hemostasis (INR <1.5) 1, 4
Do not use high-dose vitamin K (>10 mg) as this can create a prothrombotic state and is unnecessary for this level of INR elevation 5, 6
Recognize that hospitalized patients with elevated INR from underlying disease may not respond quickly to vitamin K alone and may require plasma infusion or PCC for rapid correction 3
Special Considerations for Underlying Conditions
If Liver Disease is Identified:
Patients with cirrhosis or acute liver failure have impaired synthesis of clotting factors and may require FFP or PCC for correction, as vitamin K alone will be ineffective 3
Mortality is high (74%) in patients with INR >9 from non-anticoagulant causes, emphasizing the importance of identifying and treating the underlying condition 3
If Malabsorption is Present:
Diarrhea and decreased oral intake can result in vitamin K malabsorption and INR elevation, requiring both correction of the INR and treatment of the underlying gastrointestinal condition 2
Consider parenteral vitamin K if malabsorption is severe, though oral administration is generally effective once absorption is restored 5