PT/INR
PT: 11-13.5 sec | INR: 0.8-1.1
Prothrombin Time measures extrinsic pathway clotting. INR standardizes PT for warfarin monitoring. Target INR 2-3 for most conditions, 2.5-3.5 for mechanical heart valves.
View DetailsMedical Disclaimer
- For Educational Purposes Only: This content is intended for educational reference and should not be used for clinical decision-making.
- Not a Substitute for Professional Judgment: Always consult your local protocols, institutional guidelines, and supervising physicians.
- Accuracy Not Guaranteed: While all content has been prepared to the best of my knowledge and ability, errors or omissions may exist.
- Verify Before Acting: Users are responsible for verifying information through authoritative sources before any clinical application.
AI Assistance Notice
The clinical content and references are curated and reviewed by myself; however, AI was used to assist in organizing, paraphrasing, and formatting the information presented.
Panel Overview
The Coagulation Panel (also called Coag Panel or Hemostasis Panel) evaluates the blood's ability to form clots and identifies disorders of bleeding or thrombosis. These tests assess different components of the coagulation cascade, providing critical information for diagnosing bleeding disorders, monitoring anticoagulation therapy, and evaluating thrombotic risk.
Understanding coagulation testing is essential in emergency medicine, perioperative care, and management of patients on anticoagulant medications such as warfarin, heparin, and direct oral anticoagulants (DOACs). Abnormal coagulation studies can indicate serious conditions including disseminated intravascular coagulation (DIC), liver disease, hemophilia, and thrombophilia.
Clinical Applications
- Anticoagulation Monitoring: Warfarin therapy (PT/INR), heparin therapy (aPTT), monitoring therapeutic anticoagulation
- Bleeding Disorder Evaluation: Diagnosing hemophilia, von Willebrand disease, clotting factor deficiencies, and platelet dysfunction
- Preoperative Screening: Assessing bleeding risk before surgery or invasive procedures
- Thrombosis Assessment: Evaluating hypercoagulable states, deep vein thrombosis (DVT), pulmonary embolism (PE) with D-dimer
- DIC Diagnosis: Identifying disseminated intravascular coagulation with prolonged PT/aPTT, low fibrinogen, elevated D-dimer
- Liver Disease Evaluation: Liver synthesizes clotting factors; prolonged PT/INR indicates hepatic dysfunction
Panel Components
aPTT
Normal: 25-35 seconds
Activated Partial Thromboplastin Time measures intrinsic and common pathway. Monitors heparin therapy (target 1.5-2.5× control). Prolonged in hemophilia A/B and lupus anticoagulant.
View DetailsFibrinogen
Normal: 200-400 mg/dL
Essential clotting protein converted to fibrin clot. Low in DIC, liver disease, massive hemorrhage. Elevated as acute phase reactant in inflammation, pregnancy, malignancy.
View DetailsD-dimer
Normal: <500 ng/mL (FEU)
Fibrin degradation product indicating active clot breakdown. Highly sensitive for VTE (DVT/PE) - negative D-dimer effectively rules out thrombosis. Elevated in many conditions (low specificity).
View Details