What is the significance of a decrease in Blood Pressure (BP) from 140/80 mmHg in a lying position to 120/80 mmHg in a sitting position, indicating orthostatic hypotension?

From the Guidelines

This blood pressure change from 140/80 mmHg while lying down to 120/80 mmHg when sitting does not meet the criteria for orthostatic hypotension, which is defined as a reduction of systolic blood pressure of at least 20 mm Hg or 10 mm Hg in diastolic blood pressure within 3 minutes of quiet standing, as stated in the 2024 ESC guidelines for the management of elevated blood pressure and hypertension 1. The observed change in blood pressure is a normal physiological response to changing positions.

• The body normally compensates for the effects of gravity by constricting blood vessels and increasing heart rate to maintain adequate blood flow to the brain and vital organs.
• However, it is essential to monitor for symptoms like dizziness, lightheadedness, or fainting when changing positions, as these could indicate a problem.
• If symptoms occur, recommend rising slowly from lying to sitting and then to standing, staying hydrated, and avoiding sudden position changes.
• For persistent or severe orthostatic hypotension, medication adjustments might be necessary, particularly if the patient is on antihypertensives, diuretics, or medications that affect blood pressure, as suggested by the 2024 ESC guidelines 1. The diagnosis of orthostatic hypotension is made by measuring blood pressure after a 5-min period in the seated or lying position, and then 1 and/or 3 min after standing, with a threshold of ≥20/10 mmHg drop in systolic and diastolic blood pressure, respectively 1.
• The 2024 ESC guidelines recommend assessing patients for orthostatic hypotension at the initial visit and if concerning symptoms arise 1.
• The guidelines also suggest that measurement after lying may be more sensitive for detecting orthostatic hypotension and may better predict falls, but may be less feasible than measurement after sitting in clinical practice 1.

From the FDA Drug Label

Administration of midodrine results in a rise in standing, sitting, and supine systolic and diastolic blood pressure in patients with orthostatic hypotension of various etiologies Supine and sitting blood pressure rose 16/8 and 20/10 mmHg, respectively, on average

The blood pressure decrease from 140/80 lying to 120/80 sitting is not a significant drop, and midodrine 2 is used to treat symptomatic orthostatic hypotension.

• The primary goal of midodrine is to increase blood pressure in patients with orthostatic hypotension.
• In this case, the blood pressure did not drop significantly, so midodrine may not be necessary. However, without more information about the patient's condition and medical history, it is difficult to make a definitive decision.

From the Research

Blood Pressure Changes

• The given blood pressure change from 140/80 lying to 120/80 sitting does not meet the criteria for orthostatic hypotension, which is defined as a drop in blood pressure of at least 20mmHg for systolic blood pressure and at least 10mmHg for diastolic blood pressure within 3 minutes of standing up 3.
• However, it is essential to consider the potential causes of blood pressure changes, including medications, as they can contribute to orthostatic hypotension 4, 5, 6, 7.

Medication-Related Orthostatic Hypotension

• Medications, particularly those with antihypertensive and psychoactive effects, can induce hypotensive effects and influence the blood pressure response to orthostatism 4, 5, 6, 7.
• A medication review is recommended to minimize the risk of drug-related orthostatic blood pressure impairment 4, 5, 6, 7.
• Certain medications, such as diuretics, vasodilators, tricyclic antidepressants, and antipsychotics, are more likely to cause orthostatic hypotension 5, 6, 7.

Management of Orthostatic Hypotension

• Treatment of orthostatic hypotension should focus on removing drugs that can worsen the condition and optimizing medical treatment 4, 5, 7.
• Non-pharmacological interventions, such as education on triggering situations and physiological countermaneuvers, are also essential 3.
• Pharmacological treatment may be necessary, and options include volume expansion with fludrocortisone and/or vasopressor agents like midodrine 3, 7.