Pathogenesis (development of disease)
The cause of primary (essential) hypotension is not known. It is a regulatory disorder of the circulatory system on a constitutional basis – mostly affecting leptosome (narrow-bodied) patients and women. Secondary hypotension is caused by diseases, medications and also immobility. Orthostatic hypotension also falls under this term. This occurs as a result of a shift of blood to the venous system of the legs and intestinal tract (digestive organs) that takes place when the patient stands up. This results in a temporary decrease in the supply of oxygen to the brain.
Etiology (causes) of primary hypotension
Biographic CausesParticularly commonly affected by hypotension (low blood pressure) are:
- Age
- Older people
- Adolescents in growth spurt
- Tall, slender people – so-called leptosome physique.
- Pregnant
Behavioral causes
- Consumption of stimulants
- Alcohol – (woman: > 20 g/day; man: > 30 g/day).
- Drug use
- Opiates or opioids (alfentanil, apomorphine, buprenorphine, codeine, dihydrocodeine, fentanyl, hydromorphone, loperamide, morphine, methadone, nalbuphine, naloxone, naltrexone, oxycodone, pentazocine, pethidine, piritramide, remifentanil, sufentanil, tapentadol, tilidine, tramadol)
- Physical activity
- Lack of physical activity
Causes related to disease
- Eating disorders associated with underweight
Etiology (causes) of secondary hypotension
Endocrine hypotension
- Adrenogenital syndrome (AGS) – autosomal recessive inherited metabolic disorder characterized by disorders of hormone synthesis in the adrenal cortex. These disorders lead to a deficiency of aldosterone and cortisol.
- Bartter syndrome – very rare genetic metabolic disorder with autosomal dominant or autosomal recessive or X-linked recessive inheritance; defect of tubular transport proteins; hyperaldosteronism (disease states associated with increased secretion of aldosterone), hypokalemia (potassium deficiency) and low blood pressure.
- Addison’s disease – adrenal insufficiency.
Cardiovascular hypotension
- Accretio pericardi and concretio pericardi – adhesions of the pericardium to the pleura as a result of pericarditis.
- Aortic arch syndrome, carotid sinus syndromeCardiac arrhythmias – e.g. paroxysmal tachycardia – seizure-like cardiac arrhythmia with increased heart rate above 100/min.
- Aortic stenosis – narrowing of the aorta or aortic valve.
- Heart failure (cardiac insufficiency)
- Mitral stenosis – narrowing of the mitral valve stenosis.
- Myocardial infarction (heart attack)
- Postprandial hypotension (systolic blood pressure drop of at least 20 mmHg for a period of at least 30 minutes within two hours of food intake; elderly survivors after intensive care unit stay)
Neurogenic hypotension
- After sympathectomy – removal of the sympathetic border cord.
- After administration of antihypertensive drugs, e.g., diuretics, beta-blockers, ACE inhibitors, etc.
- Shy-Drager syndrome – progressive degenerative disease of the central nervous system, which is associated with hypotension when the body is upright.
Hypovolemic hypotension due to blood or plasma loss.
- In burns, accidents, inflammation.
- Vomiting, diarrhea, extreme sweating, not drinking enough.
- In shock – decrease in the amount of circulating blood.
Medication
- Α2-agonists (apraclonidine, brimonidine, clonidine).
- ACE inhibitors (benazepril, captopril, cilazapril, enalapril, fosinopril, lisinopril, moexipril, perindopril, ramipril, spirapril, trandolapril).
- Analgesics
- Non-acid analgesics (metamizole, acetaminophen/paracetamol).
- Anaesthetics (propofol)
- Angiotension II receptor antagonists (AT-II-RB; ARB; angiotensin II receptor subtype 1 antagonists; angiotensin receptor blockers; AT1 receptor antagonists, AT1 receptor blockers, AT1 antagonists, AT1 blockers; angiotensin receptor blockers, sartans) – candesartan, eprosartan, irbesartan, losartan, olmesartan, telmisartan, valsartan).
- Antiarrhythmics
- Adenosine
- Drug class II: metoprolol
- Antidepressants
- Noradrenergic and specific serotonergic antidepressants (NaSSA) – mirtazapine.
- Selective norepinephrine reuptake inhibitors (NARI) – reboxetine, viloxazine.
- Selective serotonin–norepinephrine reuptake inhibitors (SSNRI) – duloxetine, venlafaxine.
- Selective serotonin reuptake inhibitors (SSRI) – trazodone
- Tetracyclic antidepressants (maprotiline, mianserine).
- Tricyclic antidepressants (TCA) amitriptyline, clomipramine, desipramine, doxepin, imipramine, nortriptyline, opipramol, trimipramine.
- Antihistamines (azelastine, cetirizine, clemastine, desloratardine, dimenhydrinate, dimetindene, diphenhydramine, loratardine, meclozine, terfenadine).
- Antiprotozoal agents (pentamidine).
- Antipsychotics (neuroleptics).
- Conventional (Classical) antipsychotics (neuroleptics) – haloperidol, melperone.
- Atypical antipsychotics (neuroleptics) – olanzapine, quetiapine, risperidone.
- Beta-blockers
- SS1 (acebutolol, atenolol, betaxolol, bisoprolol, celiprolol, esmolol, metoprolol, nebivolol).
- Α + ß (carvediol)
- Nadolol, oxprenolol, pindolol, propranolol
- Calcimimetic (etelcalcetide).
- Calcium antagonists (amlodipine, diltiazem, felodipine, fendiline, gallopamil, lacidipine, lercanidipine, nitrendipine, nifedipine, nimodipine, nicardipine, isradipine, nisoldipine, nilvadipine, manidipine, verapamil).
- Hormones
- Leovodopa (L-dopa)
- Dopamine agonists (α-dihydroergocriptine, bromocriptine, cabergoline, lisuride, pergolide, pramipexole, ropinirole, rotigotine)
- Mineralocorticoid antagonist (spironolactone).
- Oxytocin
- Oxytocin receptor antagonists (atosiban).
- Prostaglandin analogues (alprostadil/prostaglandin E).
- Prostanoids (epoprostenol, iloprost, treprostinil).
- Hypnotics (propofol)
- Local anesthetics (lidocaine, procaine, mepivacaine).
- Magnesium
- MAO inhibitor (tranylcypromine)
- Methylxanthines (theophylline)
- Monoclonal antibodies (trastuzumab)
- Muscle relaxants (baclofen, tizanidine).
- Nitrates (glycerol nitrate, glycerol trinitrate, isosorbide dinitrate, nitroprusside sodium).
- Phosphodiesterase III inhibitors (enoximone, milrinone).
- Rheologics (pentoxifylline).
- Sedatives
- Benzodiazepines (diazepam, flunitrazepam, midazolam, lorazepam, temazepam, tetrazepam* ) [* prescription ban since August 2013 due to serious skin reactions such as Stevens-Johnson syndrome or erythema multiforme].
- Selective α1-adrenoceptor antagonists (alfuzosin, doxazosin, tamsulosin, terazosin).
- Serotonin receptor agonists
- Thrombolytics (rt-PA).
- Vasodilators (diazoxide, dihydralazine).
- Antivirals (foscarnet, ganciclovir).
Orthostatic hypotension occurs as a result of a shift of blood to the legs and viscera that occurs when standing up. This causes a lack of blood flow to the brain, which leads to an undersupply of oxygen and, as a result, the symptoms previously described.This form of hypotension often occurs in very slim, younger women and after prolonged immobilization. Similarly, infections or hormonal dysfunction can lead to orthostatic hypotension.