Also, the heart rate should be measured for both positions. A significant increase in heart rate from supine to standing may indicate a compensatory effort by the heart to maintain cardiac output. A related syndrome, postural orthostatic tachycardia syndrome (POTS), is diagnosed when at least a 30 bpm increase in heart rate occurs with little or no change in blood pressure. A tilt table test may also be performed. Definition
Orthostatic hypotension (or postural hypotension) is a drop in blood pressure upon standing. One definition (AAFP) calls for a systolic blood pressure decrease of at least 20 mm Hg or a diastolic blood pressure decrease of at least 10 mm Hg within 3 minutes of standing. A common first symptom is lightheadedness upon standing, possibly followed by more severe symptoms: narrowing or loss of vision, dizziness, weakness, and even syncope (fainting). Subcategories
Orthostatic hypotension can be subcategorized into three groups – initial, classic, and delayed.Initial orthostatic hypotension is frequently characterized by a systolic blood pressure decrease of ≥40 mmHg or diastolic blood pressure decrease of ≥20 mmHg within 15 seconds of standing. Blood pressure then spontaneously and rapidly returns to normal, so the period of hypotension and symptoms is short (<30 s).
Additionally, the edema and loss of venous outflow impedes the arterial inflow. Ischemia with progression to gangrene are potential consequences. Phlegmasia alba dolens is distinguished, clinically, from phlegmasia cerulea dolens in that there is no ischemia and congestion. In severe cases of venous obstruction the arterial pulse may gradually disappear and venous gangrene may ensue. Diagnosis
The condition can be identified clinically & as early as possible to prevent further deterioration & complications like embolism, ischaemic necrosis, and gangrene. The diagnosis is confirmed with Doppler ultrasound of the veins of the affected leg, and occasionally other imaging modalities. Treatment
The mainstay of the treatment of deep vein thrombosis is with anticoagulation, but in very large DVTs various other modalities may be used to reduce the risk of complications. This may be surgical thrombectomy or catheter-directed thrombolysis. Etymology
Phlegmasia alba dolens literally means "painful white edema". It received the name "milk leg" because it was once thought to be caused by the metastasis of milk. References


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