In which condition is leg pain produced upon increased activity and ischemia to tissues, but then the pain is reduced with rest?

PT stands for prothrombin time, which is a measure of how long it takes the blood to clot.

INR stands for international normalized ratio, which is a way of standardizing the PT results across different laboratories.

Warfarin is a blood thinner that works by inhibiting the production of vitamin K-dependent clotting factors in the liver.

Therefore, warfarin prolongs the PT and increases the INR.The PT/INR test is used to monitor the effectiveness of warfarin therapy and adjust the dose accordingly.

Choice A is wrong because PTT stands for partial thromboplastin time, which is another measure of blood clotting time, but it reflects the activity of different clotting factors than PT.PTT is used to monitor heparin therapy, not warfarin therapy.

Choice C is wrong because aPTT stands for activated partial thromboplastin time, which is a variation of PTT that uses an activator to speed up the clotting time.Like PTT, aPTT is used to monitor heparin therapy, not warfarin therapy.

Choice D is wrong because ACT stands for activated clotting time, which is a measure of the whole blood clotting time.ACT is used to monitor high-dose heparin therapy during certain procedures, such as cardiac bypass surgery or angioplasty.

The normal ranges for these tests may vary depending on the laboratory and the method used, but generally, they are:

• PT: 10 to 13 seconds

• INR: 0.8 to 1.2 (without warfarin) or 2.0 to 3.0 (with warfarin)

• PTT: 25 to 35 seconds

• aPTT: 30 to 40 seconds

• ACT: 70 to 120 seconds

This is because digoxin inhibits the Na-K-ATPase pump on the membrane of cardiac cells, which can cause extracellular potassium levels to rise.Hypokalemia (low potassium) caused by large dosages of diuretics may result in digoxin toxicity even at low serum digoxin levels.Digoxin toxicity can cause gastrointestinal, constitutional, and/or cardiovascular symptoms, as well as ECG changes such as signs of increased automaticity and atrioventricular node blockade.

Choice B is wrong because calcium 9.2 mg/dL is within the normal range of 8.5 to 10.5 mg/dL.Hypercalcemia (high calcium) can increase sensitivity to digoxin effects and lead to toxicity even with a lower concentration of serum digoxin, but this is not the case here.

Choice C is wrong because potassium 4.8 mEq/L is within the normal range of 3.5 to 5.0 mEq/L.

Hyperkalemia (high potassium) can also increase the risk of digoxin toxicity, but this is not the case here.

Choice D is wrong because calcium 10.3 mg/dL is within the normal range of 8.5 to 10.5 mg/dL.Hypercalcemia (high calcium) can increase sensitivity to digoxin effects and lead to toxicity even with a lower concentration of serum digoxin, but this is not the case here.