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The medication midodrine can benefit people with orthostatic hypotension, The main side-effect is piloerection ("goose bumps"). Fludrocortisone is also used, although based on more limited evidence.
A number of other measures have slight evidence to support their use indomethacin, fluoxetine, dopamine antagonists, metoclopramide, domperidone, monoamine oxidase inhibitors with tyramine (can produce severe hypertension), oxilofrine, potassium chloride, and yohimbine.
Apart from treating underlying reversible causes (e.g., stopping or reducing certain medications), there are a number of measures that can improve the symptoms of orthostatic hypotension and prevent episodes of syncope. Even small increases in the blood pressure may be sufficient to maintain blood flow to the brain on standing.
In people who do not have a diagnosis of high blood pressure, drinking 2–3 liters of fluid a day and taking 10 grams of salt can improve symptoms, by maximizing the amount of fluid in the bloodstream. Another strategy is keeping the head of the bed slightly elevated. This reduces the return of fluid from the limbs to the kidneys at night, thereby reducing nighttime urine production and maintaining fluid in the circulation. Various measures can be used to improve the return of blood to the heart: the wearing of compression stockings and exercises ("physical counterpressure manoeuvres" or PCMs) that can be undertaken just before standing up (e.g., leg crossing and squatting).
Medium-term (and less well-demonstrated) treatments of hypotension include:
- Blood sugar control (80–150 by one study)
- Early nutrition (by mouth or by tube to prevent ileus)
- Steroid support
The treatment for hypotension depends on its cause. Chronic hypotension rarely exists as more than a symptom. Asymptomatic hypotension in healthy people usually does not require treatment. Adding electrolytes to a diet can relieve symptoms of mild hypotension. A morning dose of caffeine can also be effective. In mild cases, where the patient is still responsive, laying the person in dorsal decubitus (lying on the back) position and lifting the legs increases venous return, thus making more blood available to critical organs in the chest and head. The Trendelenburg position, though used historically, is no longer recommended.
Hypotensive shock treatment always follows the first four following steps. Outcomes, in terms of mortality, are directly linked to the speed that hypotension is corrected. Still-debated methods are in parentheses, as are benchmarks for evaluating progress in correcting hypotension. A study on septic shock provided the delineation of these general principles. However, since it focuses on hypotension due to infection, it is not applicable to all forms of severe hypotension.
1. Volume resuscitation (usually with crystalloid)
2. Blood pressure support with a vasopressor (all seem equivalent with respect to risk of death, with norepinephrine possibly better than dopamine). Trying to achieve a mean arterial pressure (MAP) of greater than 70 mmHg does not appear to result in better outcomes than trying to achieve a MAP of greater than 65 mm Hg in adults.
3. Ensure adequate tissue perfusion (maintain SvO2 >70 with use of blood or dobutamine)
4. Address the underlying problem (i.e., antibiotic for infection, stent or CABG (coronary artery bypass graft surgery) for infarction, steroids for adrenal insufficiency, etc...)
The best way to determine if a person will benefit from fluids is by doing a passive leg raise followed by measuring the output from the heart.
POTS treatment involves using multiple methods in combination to counteract cardiovascular dysfunction, address symptoms, and simultaneously address any associated disorders. For most patients, water intake should be increased, especially after waking, in order to expand blood volume (reducing hypovolemia). 8–10 cups of water daily are recommended. Increasing salt intake, by adding salt to food, taking salt tablets, or drinking sports drinks and other electrolyte solutions is an effective way to raise blood pressure by helping the body retain water. Different physicians recommend different amounts of sodium to their patients. Salt intake is not appropriate for people with high blood pressure. Combining these techniques with gradual physical training enhances their effect. In some cases, when increasing oral fluids and salt intake is not enough, intravenous saline or the drug desmopressin is used to help increase fluid retention.
Large meals worsen symptoms for some people. These people may benefit from eating small meals frequently throughout the day instead. Alcohol and food high in carbohydrates can also exacerbate symptoms of orthostatic hypotension. Excessive consumption of caffeine beverages should be avoided, because they can promote urine production (leading to fluid loss) and consequently hypovolemia. Exposure to extreme heat may also aggravate symptoms.
Prolonged physical inactivity can worsen the symptoms of POTS. Techniques that increase a person's capacity for exercise, such as endurance training or graded exercise therapy, can relieve symptoms for some patients. Aerobic exercise performed for 20 minutes a day, three times a week, is sometimes recommended for patients who can tolerate it. Exercise may have the immediate effect of worsening tachycardia, especially after a meal or on a hot day. In these cases, it may be easier to exercise in a semi-reclined position, such as riding a recumbent bicycle, rowing or swimming.
When changing to an upright posture, finishing a meal or concluding exercise, a sustained hand grip can briefly raise the blood pressure, possibly reducing symptoms. Compression garments can also be of benefit by constricting blood pressures with external body pressure.
If nonpharmacological methods are ineffective, medication may be necessary. As of 2013, no medication has been approved by the U.S. Food and Drug Administration to treat POTS, but a variety are used off-label. Their efficacy has not yet been examined in long-term randomized controlled trials.
Fludrocortisone may be used to enhance sodium retention and blood volume which may be beneficial not only by augmenting sympathetically-mediated vasoconstriction but also because a large subset of POTS patients appear to have low absolute blood volume.
While POTS patients typically have normal or even elevated arterial blood pressure, the neuropathic form of POTS is presumed to constitute a selective sympathetic venous denervation. In these patients the selective Alpha-1 Adrenergic receptor agonist Midodrine may increase venous return, enhance stroke volume and improve symptoms. Midodrine should only be taken during the daylight hours as it may promote supine hypertension.
Ivabradine can successfully restrain heart rate in POTS without affecting blood pressure and approximately 60% of POTS patients treated in an open-label trial of ivabradine experienced symptom improvement.
Pyridostigmine has been reported to restrain heart rate and improve chronic symptoms in about half of patients.
The selective alpha 1 agonist phenylephrine has been used successfully to enhance venous return and stroke volume in some people with POTS. However, this medication may be hampered by poor oral bioavailability.
Most patients experience an improvement of their symptoms, but for some, OI can be gravely disabling and can be progressive in nature, particularly if it is caused by an underlying condition which is deteriorating. The ways in which symptoms present themselves vary greatly from patient to patient; as a result, individualized treatment plans are necessary.
OI is treated both pharmacologically and non-pharmacologically. Treatment does not cure OI; rather, it controls symptoms.
Physicians who specialize in treating OI agree that the single most important treatment is drinking more than two liters (eight cups) of fluids each day. A steady, large supply of water or other fluids reduces most, and for some patients all, of the major symptoms of this condition. Typically, patients fare best when they drink a glass of water no less frequently than every two hours during the day, instead of drinking a large quantity of water at a single point in the day.
For most severe cases and some milder cases, a combination of medications are used. Individual responses to different medications vary widely, and a drug which dramatically improves one patient's symptoms may make another patient's symptoms much worse. Medications focus on three main issues:
Medications that increase blood volume:
- Fludrocortisone (Florinef)
- Erythropoietin
- Hormonal contraception
Medications that inhibit acetylcholinesterase:
- Pyridostigmine
Medications that improve vasoconstriction:
- Stimulants: (e.g., Ritalin or Dexedrine)
- Midodrine (ProAmatine)
- Ephedrine and pseudoephedrine (Sudafed)
- Theophylline (low-dose)
- Selective serotonin reuptake inhibitors (SSRI's - Prozac, Zoloft, and Paxil)
Behavioral changes that patients with OI can make are:
- Avoiding triggers such as prolonged sitting, quiet standing, warm environments, or vasodilating medications
- Using postural maneuvers and pressure garments
- Treating co-existing medical conditions
- Increasing fluid and salt intake
- Physical therapy and exercise unless contraindicated by an underlying condition such as chronic fatigue syndrome where traditional exercise can worsen the condition
Vasopressors may be used if blood pressure does not improve with fluids. There is no evidence of substantial superiority of one vasopressor over another; however, using dopamine leads to an increased risk of arrythmia when compared with norepinephrine. Vasopressors have not been found to improve outcomes when used for hemorrhagic shock from trauma but may be of use in neurogenic shock. Activated protein C (Xigris) while once aggressively promoted for the management of septic shock has been found not to improve survival and is associated with a number of complications. Xigris was withdrawn from the market in 2011, and clinical trials were discontinued. The use of sodium bicarbonate is controversial as it has not been shown to improve outcomes. If used at all it should only be considered if the pH is less than 7.0.
Aggressive intravenous fluids are recommended in most types of shock (e.g. 1–2 liter normal saline bolus over 10 minutes or 20 ml/kg in a child) which is usually instituted as the person is being further evaluated. Which intravenous fluid is superior, colloids or crystalloids, remains undetermined. Thus as crystalloids are less expensive they are recommended. If the person remains in shock after initial resuscitation packed red blood cells should be administered to keep the hemoglobin greater than 100 g/l.
For those with haemorrhagic shock the current evidence supports limiting the use of fluids for penetrating thorax and abdominal injuries allowing mild hypotension to persist (known as permissive hypotension). Targets include a mean arterial pressure of 60 mmHg, a systolic blood pressure of 70–90 mmHg, or until their adequate mentation and peripheral pulses.
The main goals of treatment in distributive shock are to reverse the underlying cause and achieve hemodynamic stabilization. Immediate treatment involves fluid resuscitation and the use of vasoactive drugs, both vasopressors and inotropes. Hydrocortisone is used for patients whose hypotension does not respond to fluid resuscitation and vasopressors. Opening and keeping open the microcirculation is a consideration in the treatment of distributive shock, as a result limiting the use of vasopressors has been suggested. Control of inflammation, vascular function and coagulation to correct pathological differences in blood flow and microvascular shunting has been pointed to as a potentially important adjunct goal in the treatment of distributive shock.
Patients with septic shock are treated with antimicrobial drugs to treat the causative infection. Some sources of infection require surgical intervention including necrotizing fasciitis, cholangitis, abscess, intestinal ischemia, or infected medical devices.
Anaphylactic shock is treated with epinephrine.
Septic shock is associated with significant mortality and is the leading non cardiac cause of death in intensive care units (ICUs).
Not required for physiologic sinus tachycardia. Underlying causes are treated if present.
Acute myocardial infarction. Sinus tachycardia can present in more than a third of the patients with AMI but this usually decreases over time. Patients with sustained sinus tachycardia reflects a larger infarct that are more anterior with prominent left ventricular dysfunction, associated with high mortality and morbidity. Tachycardia in the presence of AMI can reduce coronary blood flow and increase myocardial oxygen demand, aggravating the situation. Beta blockers can be used to slow the rate, but most patients are usually already treated with beta blockers as a routine regimen for AMI.
Practically, many studies showed that there is no need for any treatment.
IST and POTS. Beta blockers are useful if the cause is sympathetic overactivity. If the cause is due to decreased vagal activity, it is usually hard to treat and one may consider radiofrequency catheter ablation.
While CSWS usually appears within the first week after brain injury and spontaneously resolves in 2–4 weeks, it can sometimes last for months or years. In contrast to the use of fluid restriction to treat SIADH, CSWS is treated by replacing the urinary losses of water and sodium with hydration and sodium replacement. The mineralocorticoid medication fludrocortisone can also improve the low sodium level.
The tilt table test is an evaluative clinical test to help identify postural hypotension, a common cause of presyncope or syncope. A tilt angle of 60 and 70 degrees is optimal and maintains a high degree of specificity. A positive sign with the tilt table test must be taken in context of patient history, with consideration of pertinent clinical findings before coming to a conclusion.
IST has been treated both pharmacologically and invasively, with varying degrees of success. IST, in and of itself, is not indicative of higher rates of mortality, and non-treatment is an option chosen by many if they have minimal symptoms.
Some types of medication tried by cardiologists and other physicians include: beta blockers, selective sinus node I channel inhibitors (ivabradine), calcium channel blockers and antiarrhythmic agents. Some SSRI drugs are also occasionally tried and also treatments more commonly used to treat postural orthostatic tachycardia syndrome such as fludrocortisone. This approach is very much "trial-and-error". Patients with IST are often intolerant to beta blockers. A new selective sinus node inhibitor ivabradine is also being used to treat IST.
Invasive treatments include forms of catheter ablation such as sinus node modification (selective ablation of the sinus node), complete sinus node ablation (with associated implantation of a permanent artificial pacemaker) and AV node ablation in very resistant cases (creation of iatrogenic complete heart block, necessitating implantation of a permanent artificial pacemaker).
However invasive treatments can also make the symptoms worse, not cure it. Treatment should be chosen with care as the patient could become in need of a pacemaker or have more extensive symptoms.
In those that are unstable with a narrow complex tachycardia, intravenous adenosine may be attempted. In all others immediate cardioversion is recommended.
The treatment of dysautonomia can be difficult; since it is made up of many different symptoms, a combination of drug therapies is often required to manage individual symptomatic complaints. Therefore, if an autoimmune neuropathy is the case, then treatment with immunomodulatory therapies is done, or if diabetes mellitus is the cause, control of blood glucose is important. Treatment can include proton-pump inhibitors and H2 receptor antagonists used for digestive symptoms such as acid reflux.
For the treatment of genitourinary autonomic neuropathy medications may include sildenafil (a guanine monophosphate type-5 phosphodiesterase inhibitor). For the treatment of hyperhidrosis, anticholinergic agents such as trihexyphenidyl or scopolamine can be used, also intracutaneous injection of botulinum toxin type A can be used for management in some cases.
Balloon angioplasty, a procedure referred to as transvascular autonomic modulation, is specifically not approved for the treatment of autonomic dysfunction.
Since the conversion of dihydroxyphenylserine (Droxidopa; trade name: Northera; also known as L-DOPS, L-threo-dihydroxyphenylserine, L-threo-DOPS and SM-5688), to norepinephrine bypasses the dopamine beta-hydroxylation step of catecholamine synthesis, L-Threo-DOPS is the ideal therapeutic agent. In humans with DβH deficiency, L-Threo-DOPS, a synthetic precursor of noradrenaline, administration has proven effective in dramatic increase of blood pressure and subsequent relief of postural symptoms.
L-DOPS continues to be studied pharmacologically and pharmacokinetically and shows an ability to increase the levels of central nervous system norepinephrine by a significant amount. This is despite the fact that L-DOPS has a relative difficulty crossing the blood-brain barrier when compared to other medications such as L-DOPA. When used concurrently, there is evidence to show that there is increased efficacy as they are both intimately involved and connected to the pathway in becoming norepinephrine.
There is hope and evidence that L-DOPS can be used much more widely to help other conditions or symptoms such as pain, chronic stroke symptoms, and progressive supranuclear palsy, amongst others. Clinically, L-DOPS has been already shown to be helpful in treating a variety of other conditions related to hypotension including the following:
- Diabetes induced orthostatic hypotension
- Dialysis-induced hypotension
- Orthostatic intolerance
- Familial amyloidotic polyneuropathy
- Spinal Cord Injury related hypotension
Empirical evidence of mild effectiveness has been reported using mineralocorticoids or adrenergic receptor agonists as therapies.
Other medications that can bring relief to symptoms include:
- phenylpropanolamine- due to pressor response to vascular α-adrenoceptors
- indomethacin
Vitamin C (ascorbic acid) is also a required cofactor for the Dopamine beta hydroxylase enzyme. Recent research has shown that vitamin C rapidly catalyzes the conversion of dopamine to norepinephrine through stimulation of the dopamine beta hydroxylase enzyme.
Untreated individuals with DβH deficiency should avoid hot environments, strenuous exercise, standing still, and dehydration.
Presyncope is a state of lightheadedness, muscular weakness, blurred vision, and feeling faint (as opposed to a syncope, which is actually fainting). Presyncope is most often cardiovascular in cause. In many people, lightheadedness is a symptom of orthostatic hypotension. Orthostatic hypotension occurs when blood pressure drops significantly when the patient stands from a supine (horizontal) or seatted position. If loss of consciousness occurs in this situation, it is termed syncope.
Presyncope is frequently reported in people with autonomic dysfunctions such as the postural orthostatic tachycardia syndrome (POTS).
Pharmacological methods of treatment include fludrocortisone, midodrine, somatostatin, erythropoietin, and other vasopressor agents. However, often a patient with pure autonomic failure can mitigate his or her symptoms with far less costly means. Compressing the legs and lower body, through crossing the legs, squatting, or the use of compression stockings can help. Also, ingesting more water than usual can increase blood pressure and relieve some symptoms.
Proper treatment of autonomic dysreflexia involves administration of anti-hypertensives along with immediate determination and removal of the triggering stimuli. Often, sitting the patient up and dangling legs over the bedside can reduce blood pressures below dangerous levels and provide partial symptom relief. Tight clothing and stockings should be removed. Straight catheterization of the bladder every 4 to 6 hrs, or relief of a blocked urinary catheter tube may resolve the problem. The rectum should be cleared of stool impaction, using anaesthetic lubricating jelly. If the noxious precipitating trigger cannot be identified, drug treatment is needed to decrease elevating intracranial pressure until further studies can identify the cause.
Drug treatment includes the rapidly acting vasodilators, including sublingual nitrates or oral clonidine. Ganglionic blockers are also used to control sympathetic nervous system outflow. Topical nitropaste is a convenient and safe treatment—an inch or two can be applied to the chest wall, and wiped off when blood pressures begin to normalize. Autonomic dysreflexia is abolished temporarily by spinal or general anaesthesia. These treatments are used during obstetric delivery of a woman with autonomic dysreflexia.
The report of Da Costa shows that patients recovered from the more severe symptoms when removed from the strenuous activity or sustained lifestyle that caused them. A reclined position and forced bed rest was the most beneficial.
Other treatments evident from the previous studies were improving physique and posture, appropriate levels of exercise where possible, wearing loose clothing about the waist, and avoiding postural changes such as stooping, or lying on the left or right side, or the back in some cases, which relieved some of the palpitations and chest pains, and standing up slowly can prevent the faintness associated with postural or orthostatic hypotension in some cases.
Pharmacological intervention came in the form of digitalis, or "fox glove", which acts as a sodium-potassium ATPase inhibitor, increasing stroke volume and decreasing heart rate.
The clinician must protect the patient against hypotension, renal failure, acidosis, hyperkalemia and hypocalcemia. Admission to an intensive care unit, preferably one experienced in trauma medicine, may be appropriate; even well-seeming patients need observation. Treat open wounds as surgically appropriate, with debridement, antibiotics and tetanus toxoid; apply ice to injured areas.
Intravenous hydration of up to 1.5 L/hour should continue to prevent hypotension. A urinary output of at least 300 ml/hour should be maintained with IV fluids and mannitol, and hemodialysis considered if this amount of diuresis is not achieved. Use intravenous sodium bicarbonate to keep the urine pH at 6.5 or greater, to prevent myoglobin and uric acid deposition in kidneys.
To prevent hyperkalemia/hypocalcemia, consider the following adult doses:
- calcium gluconate 10% 10ml or calcium chloride 10% 5 ml IV over 2 minutes
- sodium bicarbonate 1 meq/kg IV slow push
- regular insulin 5–10 U
- 50% glucose 1–2 ampules IV bolus
- kayexalate 25–50 g with sorbitol 20% 100 ml by mouth or rectum.
Even so, cardiac arrhythmias may develop; electrocardiographic monitoring is advised, and specific treatment begun promptly.
Diet alone cannot treat pacemaker syndrome, but an appropriate diet to the patient, in addition to the other treatment regimens mentioned, can improve the patient's symptoms. Several cases mentioned below:
- For patients with heart failure, low-salt diet is indicated.
- For patients with autonomic insufficiency, a high-salt diet may be appropriate.
- For patients with dehydration, oral fluid rehydration is needed.