Severe hypotension / Shock

Severe hypotension is when the blood pressure is below 50/30 mmHg, well below what is considered normal.

There are many causes of low blood pressure: large blood loss, dehydration, a serious infection, a severe allergic reaction, a heart attack, an irregular heartbeat or heart failure, and even a sudden change in body position. Some drugs or substances can also cause low blood pressure (alcohol, anxiolytics, antidepressants, diuretics, hypotension).

Symptoms include blurred vision, dizziness, lightheadedness, weakness, nausea or vomiting, drowsiness, chest pain, headache, palpitations and/or fainting.

Diagnosis is made by measuring vital signs (blood pressure, heart rate, temperature, respiratory rate and/or blood glucose control). It should be supplemented by a detailed medical history and, in many cases, by blood analysis, blood cultures, electrocardiogram, abdominal and/or chest x-ray and urinalysis.

It is important to treat the cause of the hypotension. If it is due to fluid loss, this should be replaced by intravenous fluid therapy or blood transfusion; if there is active bleeding, urgent surgery may be required. If there is an infection, treatment will be based on antibiotics. If it is due to a severe allergy (anaphylaxis), contact with the allergenic substance will be avoided and antihistamines and/or corticosteroids will be given. In more severe cases, medication to raise blood pressure will be needed. If the hypotension has been caused by a rapid change of position, it may be relieved by lying down and raising the legs to facilitate the return of blood.

In cases of more severe hypotension, ask for help or go to the nearest emergency room because low blood pressure can deprive vital organs such as the heart or brain of oxygen, which can have serious consequences. If the person stops breathing or has no pulse, cardiopulmonary resuscitation (CPR) should be started.