Is prothrombin time 13.3 normal

Prothrombin time of 13.3 seconds is within the normal range. The normal value of prothrombin time (PT) is usually 11-14 seconds, and the specific reference range may vary slightly depending on the testing method, reagent brand, and laboratory standards. The factors that affect PT values mainly include the use of anticoagulant drugs, vitamin K deficiency, liver disease, genetic coagulation factor deficiency, and blood dilution status.

1. Anticoagulant effects:

Vitamin K antagonists such as warfarin can significantly prolong PT values. These drugs exert anticoagulant effects by inhibiting the synthesis of coagulation factors II, VII, IX, and X. During medication, it is necessary to regularly monitor the international normalized ratio of INR values rather than simply looking at PT seconds. If antibiotics or antipyretic analgesics are taken simultaneously, it may enhance the effectiveness of warfarin.

2. Vitamin K metabolism:

Vitamin K is an essential substance for synthesizing clotting factors. Long term diarrhea, biliary obstruction, or insufficient intake can lead to vitamin K deficiency. Green leafy vegetables, animal liver, and other foods are rich in vitamin K, and disrupted gut microbiota may also affect their absorption. Newborns are prone to vitamin K deficiency bleeding due to a sterile intestinal environment.

3. Abnormal liver function:

Chronic hepatitis, cirrhosis and other liver diseases can lead to reduced synthesis of coagulation factors. The liver is the main organ that produces clotting factors. When liver function is impaired, in addition to PT prolongation, APTT prolongation and platelet reduction are often accompanied. These patients may experience symptoms such as gum bleeding and subcutaneous bruising.

4. Genetic diseases:

Hemophilia B factor IX deficiency or rare genetic factor VII deficiency can lead to prolonged PT alone. This type of disease often has a family history, and symptoms such as joint cavity bleeding and abnormal postoperative bleeding may occur in childhood. Genetic testing and coagulation factor activity testing can provide a clear diagnosis.

5. physiological fluctuations:

Mild shortening of PT may occur during menstruation and mid to late pregnancy. The state of blood dilution, such as excessive infusion, may cause pseudoprolongation of PT. Factors such as poor blood collection during testing and improper proportion of anticoagulants can also affect the accuracy of the results. Maintaining a balanced diet can help maintain normal coagulation function. It is recommended to consume 300-500 grams of fresh vegetables per day, with dark green leafy vegetables accounting for more than half of the total. Moderate exercise can promote blood circulation, but hemophilia patients should avoid intense confrontational exercise. During regular physical examinations, it is recommended to combine the four coagulation parameters PT, APTT, TT, FIB with platelet count testing. Those taking anticoagulant drugs should adjust their dosage according to medical advice. If abnormal bleeding tendency or continuous enlargement of skin bruising is found, medical attention should be sought in a timely manner.