What should you know about hypotension pathophysiology?

Blood pressure depends on the amount of blood the heart pumps, the heart's rhythm and strength, the volume of fluid in the bloodstream, and the tension of blood vessel walls. The nervous system normally adjusts these factors when you stand, exercise, become dehydrated, or lose fluid. Hypotension can occur when the heart pumps less effectively, blood vessels relax too much, or the circulating volume falls.

When pressure drops, the brain may briefly receive less blood, causing light-headedness, blurred vision, weakness, nausea, or fainting. Some people have low readings without symptoms, while others feel unwell after a modest change. The meaning of a reading depends on symptoms, timing, medicines, illness, and the person's usual blood pressure.

Record when symptoms happen, including whether they follow standing, meals, heat, exertion, vomiting, diarrhoea, or a change in medicine. Sit or lie down promptly when light-headed, and rise in stages. Keep fluids available unless a clinician has restricted them, and do not stop prescribed medicines without advice. A GP assessment can compare readings in different positions and review hydration, heart symptoms, and medicines.

Seek urgent help for fainting with chest pain, severe breathlessness, a new irregular heartbeat, confusion, a serious injury, heavy bleeding, or signs of shock such as cold clammy skin and extreme weakness. Arrange medical review for repeated dizziness, falls, fainting, or symptoms that are worsening. A sudden drop during an acute illness also needs prompt assessment.

Ask what may be lowering your pressure, whether your medicines or fluid intake need review, and which readings or symptoms should prompt urgent care.