At what point (if ever) is low blood pressure considered dangerous?

Answer 1

Hypotension ICD-10 I95.
ICD-9 458

In physiology and medicine, hypotension refers to an abnormally low blood pressure. This is best understood as a physiologic state, rather than a disease. It is often associated with shock, though not necessarily indicative of it. Hypotension is not to be confused with hypertension.

Normal physiology

Blood pressure is continuously regulated by the autonomic nervous system, using an elaborate network of receptors, nerves, and hormones to balance the effects of the sympathetic nervous system, which tends to raise blood pressure, and the parasympathetic nervous system, which lowers it. The vast and rapid compensation abilities of the autonomic nervous system allow normal individuals to maintain an acceptable blood pressure over a wide range of activities and in many disease states.


Mechanisms and Causes

Reduced blood volume, called hypovolemia, is the most common mechanism producing hypotension. This can result from hemorrhage, or blood loss; insufficient fluid intake, as in starvation; or excessive fluid losses from diarrhea or vomiting. Hypovolemia is often induced by excessive use of diuretics. (Other medications can produce hypotension by different mechanisms.)

Decreased cardiac output despite normal blood volume, due to severe congestive heart failure, large myocardial infarction, or bradycardia, often produces hypotension and can rapidly progress to cardiogenic shock. Arrhythmias often result in hypotension by this mechanism. Beta blockers can cause hypotension both by slowing the heart rate and by decreasing the pumping ability of the heart muscle.

Excessive vasodilation, or insufficient constriction of the resistance blood vessels (mostly arterioles), causes hypotension. This can be due to decreased sympathetic nervous system output or to increased parasympathetic activity occurring as a consequence of injury to the brain or spinal cord or of dysautonomia, an intrinsic abnormality in autonomic system functioning. Excessive vasodilation can also result from sepsis, acidosis, or medications, such as nitrate preparations, calcium channel blockers, or ACE inhibitors. Many anesthetic agents and techniques, including spinal anesthesia and most inhalational agents, produce significant vasodilation.

Syndromes

Orthostatic hypotension, also called "postural hypotension", is a common form of low blood pressure. It occurs after a change in body position, typically when a person stands up from either a seated or lying position. It is usually transient and represents a delay in the normal compensatory ability of the autonomic nervous system. It is commonly seen in hypovolemia and as a result of various medications. In addition to the classes of blood pressure-lowering medications listed above, many psychiatric medications, in particular antidepressants, can have this side effect. Simple blood pressure and heart rate measurements while lying, seated, and standing can confirm the presence of orthostatic hypotension.

Neurocardiogenic Syncope is a form of dysautonomia characterized by an inappropriate drop in blood pressure while in the upright position. Tilt-table testing is used to evaluate this. Neurocardiogenic syncope is related to vasovagal syncope in that both occur as a result of increased activity of the vagus nerve, the mainstay of the parasympathetic nervous system..

Another—albeit rare—form, is Postprandial hypotension, which occurs 30-75 minutes after eating. Because digestion sends a great deal of blood to the intestines, the body must increase heart rate and vasoconstriction to compensate for local blood volume changes. It is believed that this form of hypotension is caused by a disordered or aging autonomic nervous system not compensating appropriately while digestion takes place.

Indicators

For most individuals, a healthy blood pressure lies between 90/50 mmHg to 135/90 mmHg. A small drop in blood pressure, even as little as 20 mmHg, can result in transient hypotension.

Symptoms

The cardinal symptom of hypotension is lightheadedness or dizziness. If the blood pressure is sufficiently low, syncope and often seizures will occur.

Low blood pressure is often accompanied by: (Most of these are related to causes rather than effects of hypotension.)

* Chest pain
* Shortness of breath
* Irregular heartbeat
* Fever higher than 101 °F (38.3 °C)
* Headache
* Stiff neck
* Severe upper back pain
* Cough with phlegm
* Prolonged diarrhea or vomiting
* Inability to eat or drink
* Burning with urination
* Foul-smelling urine
* Adverse effect of medications
* Acute, life-threatening allergic reaction
* Dizziness, or light-headedness
* Seizures
* Loss of consciousness
* Profound fatigue

Answer 2

A skipped heart beat sometimes can be described as a "fluttering" feeling in your chest however, most people never actually feel it. Skipped beats are potentially dangerous if you have too many as it could mean that the heart isnt pumping blood effectively. This is very rare, though. There are a few causes of skipped beats. The most common is called premature ventricular contractions or PVC's. It just means that the bottom 2 chambers of the heart contracted before they were supposed to do so and therefore could not do it when it was time to do so. Another cause is premature atrial contractions or PAC's. PAC's still produce a heartbeat but because it happened before it was supposed to, some people notice that their pulse is irregular making them think that their heart skipped a beat. There are numerous other causes including drugs, caffiene, and nicotine but there are too many to go into here. Usually the cause of the skipped beat is much more important to know than the skipped beat itself. I would suggest going to the doctor and monitoring your pulse on a regular basis, both at rest and when active to give the doc something to go on. Good Luck.

Answer 3

hi
for the blood pressure i will help you
as a pharmacy student i will tell that 150/950 considered as a high blood pressure , but you can also take into your account that 140/90 is a high one
so it depends to the person and to the body of that person
hope that i helped
take care
bye

Answer 4

What is considered the "normal" range is 120/80 to 139/89. Now, the reality is that is depends on the individual. Everybody has a different baseline.

Answer 5

It is dangerous when the pressure is inadequate to properly circulate blood throughout the entire body.

Answer 6

only if you get too dizzy when standing up, or feel weak. Having low-ish blood pressure is quite healthy. If you are dizzy, though, be sure to keep well-hydrated to keep the blood volume up.

Answer 7

I have lazy blood, it just can't be bothered to go all the way round...

It isn't dangerous as long as I insert a foot pump into my foot and pump it the rest of the way,

I hope this helps

Regards

Ichi