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It is the goal of evolutionary medicine to find treatments for diseases that are informed by the evolutionary history of a disease. It has been suggested that gestational hypertension is linked to insulin resistance during pregnancy. Both the increase in blood sugar that can lead to gestational diabetes and the increase in blood pressure that can lead to gestational hypertension are mechanisms that mean to optimize the amount of nutrients that can be passed from maternal tissue to fetal tissue. It has been suggested that techniques used to combat insulin insensitivity might also prove beneficial to those suffering from gestational hypertension. Measures to avoid insulin resistance include avoiding obesity before pregnancy, minimizing weight gain during pregnancy, eating foods with low glycemic indexes, and exercising.
There is no specific treatment, but is monitored closely to rapidly identify pre-eclampsia and its life-threatening complications (HELLP syndrome and eclampsia).
Drug treatment options are limited, as many antihypertensives may negatively affect the fetus. Methyldopa, hydralazine, and labetalol are most commonly used for severe pregnancy hypertension.
The fetus is at increased risk for a variety of life-threatening conditions, including pulmonary hypoplasia (immature lungs). If the dangerous complications appear after the fetus has reached a point of viability, even though still immature, then an early delivery may be warranted to save the lives of both mother and baby. An appropriate plan for labor and delivery includes selection of a hospital with provisions for advanced life support of newborn babies.
Taking aspirin is associated with a 1% to 5% reduction in pre-eclampsia and a 1% to 5% reduction in premature births in women at high risk. The World Health Organization recommends low-dose aspirin for the prevention of pre-eclampsia in women at high risk and recommends it be started before 20 weeks of pregnancy. The United States Preventive Services Task Force recommends a low-dose regimen for women at high risk beginning in the 12th week. Benefits are less if started after 16 weeks.
Certain medications, including NSAIDs (Motrin/Ibuprofen) and steroids can cause hypertension. Other medications include extrogens (such as those found in oral contraceptives with high estrogenic activity), certain antidepressants (such as venlafaxine), buspirone, carbamazepine, bromocriptine, clozapine, and cyclosporine.
High blood pressure that is associated with the sudden withdrawal of various antihypertensive medications is called rebound hypertension. The increases in blood pressure may result in blood pressures greater than when the medication was initiated. Depending on the severity of the increase in blood pressure, rebound hypertension may result in a hypertensive emergency. Rebound hypertension is avoided by gradually reducing the dose (also known as "dose tapering"), thereby giving the body enough time to adjust to reduction in dose. Medications commonly associated with rebound hypertension include centrally-acting antihypertensive agents, such as clonidine and methyl-dopa.
Other herbal or "natural products" which have been associated with hypertension include ma huang, St John's wort, and licorice.
In low-risk pregnancies, the association between cigarette smoking and a reduced risk of pre-eclampsia has been consistent and reproducible across epidemiologic studies. High-risk pregnancies (those with pregestational diabetes, chronic hypertension, history of pre-eclampsia in a previous pregnancy, or multifetal gestation) showed no significant protective effect. The reason for this discrepancy is not definitively known; research supports speculation that the underlying pathology increases the risk of preeclampsia to such a degree that any measurable reduction of risk due to smoking is masked. However, the damaging effects of smoking on overall health and pregnancy outcomes outweighs the benefits in decreasing the incidence of preeclampsia. It is recommended that smoking be stopped prior to, during and after pregnancy.
Studies suggest that marijuana use in the months prior to or during the early stages of pregnancy may interfere with normal placental development and consequently increase the risk of preeclampsia.
Regular physical exercise reduces blood pressure. The UK National Health Service advises 150 minutes (2 hours and 30 minutes) of moderate-intensity aerobic activity per week to help prevent hypertension.
Hypertension is one of the most common complex disorders. The etiology of hypertension differs widely amongst individuals within a large population. And by definition, essential hypertension has no identifiable cause. However, several risk factors have been identified.
Few women of childbearing age have high blood pressure, up to 11% develop hypertension of pregnancy. While generally benign, it may herald three complications of pregnancy: pre-eclampsia, HELLP syndrome and eclampsia. Follow-up and control with medication is therefore often necessary.
The four goals of the treatment of eclampsia are to stop and prevent further convulsions, to control the elevated blood pressure, to deliver the baby as promptly as possible, and to monitor closely for the onset of multi-organ failure.
Hypertension results from a complex interaction of genes and environmental factors. Numerous common genetic variants with small effects on blood pressure have been identified as well as some rare genetic variants with large effects on blood pressure. Also, genome-wide association studies (GWAS) have identified 35 genetic loci related to blood pressure; 12 of these genetic loci influencing blood pressure were newly found. Sentinel SNP for each new genetic loci identified has shown an association with DNA methylation at multiple nearby Cpg sites. These sentinel SNP are located within genes related to vascular smooth muscle and renal function. DNA methylation might affect in some way linking common genetic variation to multiple phenotypes even though mechanisms underlying these associations are not understood. Single variant test performed in this study for the 35 sentinel SNP (known and new) showed that genetic variants singly or in aggregate contribute to risk of clinical phenotypes related to high blood pressure.
Blood pressure rises with aging and the risk of becoming hypertensive in later life is considerable. Several environmental factors influence blood pressure. High salt intake raises the blood pressure in salt sensitive individuals; lack of exercise, obesity, and depression can play a role in individual cases. The possible role of other factors such as caffeine consumption, and vitamin D deficiency are less clear. Insulin resistance, which is common in obesity and is a component of syndrome X (or the metabolic syndrome), is also thought to contribute to hypertension. One review suggests that sugar may play an important role in hypertension and salt is just an innocent bystander.
Events in early life, such as low birth weight, maternal smoking, and lack of breastfeeding may be risk factors for adult essential hypertension, although the mechanisms linking these exposures to adult hypertension remain unclear. An increased rate of high blood urea has been found in untreated people with hypertensive in comparison with people with normal blood pressure, although it is uncertain whether the former plays a causal role or is subsidiary to poor kidney function. Average blood pressure may be higher in the winter than in the summer.
Detection and management of pre-eclampsia is critical to reduce the risk of eclampsia. The USPSTF recommends regular checking of blood pressure through pregnancy in order to detect preeclampsia. Appropriate management of women with pre-eclampsia generally involves the use of magnesium sulphate to prevent convulsions.
Secondary hypertension results from an identifiable cause. Kidney disease is the most common secondary cause of hypertension. Hypertension can also be caused by endocrine conditions, such as Cushing's syndrome, hyperthyroidism, hypothyroidism, acromegaly, Conn's syndrome or hyperaldosteronism, renal artery stenosis (from atherosclerosis or fibromuscular dysplasia), hyperparathyroidism, and pheochromocytoma. Other causes of secondary hypertension include obesity, sleep apnea, pregnancy, coarctation of the aorta, excessive eating of liquorice, excessive drinking of alcohol, and certain prescription medicines, herbal remedies, and illegal drugs such as cocaine and methamphetamine. Arsenic exposure through drinking water has been shown to correlate with elevated blood pressure.
The initial aim of treatment in hypertensive crises is to rapidly lower the diastolic pressure to about 100 to 105 mmHg; this goal should be achieved within two to six hours, with the maximum initial fall in BP not exceeding 25 percent of the presenting value. This level of BP control will allow gradual healing of the necrotizing vascular lesions. More aggressive hypotensive therapy is both unnecessary and may reduce the blood pressure below the autoregulatory range, possibly leading to ischemic events (such as stroke or coronary disease).
Once the BP is controlled, the person should be switched to medication by mouth, with the diastolic pressure being gradually reduced to 85 to 90 mmHg over two to three months. The initial reduction to a diastolic pressure of approximately 100 mmHg is often associated with a modest worsening of renal function; this change, however, is typically transient as the vascular disease tends to resolve and renal perfusion improves over one to three months. Antihypertensive therapy should not be withheld in this setting unless there has been an excessive reduction in BP. A change in medication, however, is indicated if the decline in renal function is temporally related to therapy with an angiotensin (ACE) converting enzyme inhibitor or angiotensin II receptor blocker, which can interfere with renal autoregulation and produce acute renal failure in patients with bilateral renal artery stenosis. (See "Renal effects of ACE inhibitors in hypertension".)
Several parenteral antihypertensive agents are most often used in the initial treatment of malignant hypertension.
- Nitroprusside – an arteriolar and venous dilator, given as an intravenous infusion. Nitroprusside acts within seconds and has a duration of action of only two to five minutes. Thus, hypotension can be easily reversed by temporarily discontinuing the infusion, providing an advantage over the drugs listed below. However, the potential for cyanide toxicity limits the prolonged use of nitroprusside, particularly in patients with renal insufficiency.
- Nicardipine – an arteriolar dilator, given as an intravenous infusion.
- Clevidipine – a short-acting dihydropyridine calcium channel blocker. It reduces blood pressure without affecting cardiac filling pressures or causing reflex tachycardia.
- Labetalol – an alpha- and beta-adrenergic blocker, given as an intravenous bolus or infusion. Bolus followed by infusion.
- Fenoldopam – a peripheral dopamine-1 receptor agonist, given as an intravenous infusion.
- Oral agents — A slower onset of action and an inability to control the degree of BP reduction has limited the use of oral antihypertensive agents in the therapy of hypertensive crises. They may, however, be useful when there is no rapid access to the parenteral medications described above. Both sublingual nifedipine and sublingual captopril can substantially lower the BP within 10 to 30 minutes in many patients. A more rapid response is seen when liquid nifedipine is swallowed.
The major risk with oral agents is ischemic symptoms (e.g., angina pectoris, myocardial infarction, or stroke) due to an excessive and uncontrolled hypotensive response. Thus, their use should generally be avoided in the treatment of hypertensive crises if more controllable drugs are available.
Patients with hypertensive encephalopathy who are promptly treated usually recover without deficit. However, if treatment is not administered, the condition can lead to death.
The first step in management of uterine atony is uterine massage. The next step is pharmacological therapies, the first of which is oxytocin, used because it initiates rhythmic contractions of the uterus, compressing the spiral arteries which should reduce bleeding. The next step in the pharmacological management is the use of methylergometrine, which is an ergot derivative, much like that use in the abortive treatment of migraines. Its side effect of hypertension means its use should not be used in those with hypertension or pre-eclampsia. In those with hypertension, the use of prostaglandin F is indicated (but beware of its use in patients with asthma).
Another option Carbetocin and Carboprost where Oxytocin and ergometrin is inappropriate.
With treatment, maternal mortality is about 1 percent, although complications such as placental abruption, acute renal failure, subcapsular liver hematoma, permanent liver damage, and retinal detachment occur in about 25% of women. Perinatal mortality (stillbirths plus death in infancy) is between 73 and 119 per 1000 babies of woman with HELLP, while up to 40% are small for gestational age. In general, however, factors such as gestational age are more important than the severity of HELLP in determining the outcome in the baby.
Ideally a woman who is known to have hyperthyroidism should seek pre-pregnancy advice, although as yet there is no evidence for its benefit. Appropriate education should allay fears that are commonly present in these women. She should be referred for specialist care for frequent checking of her thyroid status, thyroid antibody evaluation and close monitoring of her medication needs. Medical therapy with anti-thyroid medications is the treatment of choice for hyperthyroidism in pregnancy.Methimazole and propylthiouracil (PTU) are effective in preventing pregnancy complications by hyperthyroidism. Surgery is considered for patients who suffer severe adverse reactions to anti-thyroid drugs and this is best performed in the second trimester of pregnancy. Radioactive iodine is absolutely contraindicated in pregnancy and the puerperium. If a woman is already receiving carbimazole, a change to propylthiouracil (PTU) is recommended but this should be changed back to carbimazole after the first trimester. This is because carbimazole can rarely be associated with skin and also mid line defects in the fetus but PTU long term also can cause liver side effects in the adult. Carbimazole and PTU are both secreted in breast milk but evidence suggests that antithyroid drugs are safe during lactation. There are no adverse effects on IQ or psychomotor development in children whose mothers have received antithyroid drugs in pregnancy.
Current guidelines suggest that a pregnant patient should be on PTU during the first trimester of pregnancy due to lower tetragenic effect and then be switched to methimazole during the second and third trimester due to lower liver dysfunction side effects.
Benign hypertension or benign essential hypertension are historical terms that are considered misleading as hypertension is never benign, and consequently they have fallen out of use (see history of hypertension). The terminology persisted in the International Classification of Disease (ICD9) but is not included in the current ICD10.
The only effective treatment is prompt delivery of the baby. Several medications have been investigated for the treatment of HELLP syndrome, but evidence is conflicting as to whether magnesium sulfate decreases the risk of seizures and progress to eclampsia. The disseminated intravascular coagulation is treated with fresh frozen plasma to replenish the coagulation proteins, and the anemia may require blood transfusion. In mild cases, corticosteroids and antihypertensives (labetalol, hydralazine, nifedipine) may be sufficient. Intravenous fluids are generally required. Hepatic hemorrhage can be treated with embolization, as well, if life-threatening bleeding ensues.
The University of Mississippi standard protocol for HELLP includes corticosteroids. However, a 2009 review found "no conclusive evidence" supporting corticosteroid therapy, and a 2010 systematic review by the Cochrane Collaboration also found "no clear evidence of any effect of corticosteroids on substantive clinical outcomes" either for the mothers or for the newborns,
Oxytocin is typically used right after the delivery of the baby to prevent PPH. Misoprostol may be used in areas where oxytocin is not available. Early clamping of the umbilical cord does not decrease risks and may cause anemia in the baby, thus is usually not recommended.
Active management of the third stage is a method of shortening the stage between when the baby is born and when the placenta is delivered. This stage is when the mother is at risk of having a PPH. Active management involves giving a drug which helps the uterus contract before delivering the placenta by a gentle but sustained pull on the umbilical cord whilst exerting upward pressure on the lower abdomen to support the uterus.
Another method of active management which is not recommended now is fundal pressure. A review into this method found no research and advises controlled cord traction because fundal pressure can cause the mother unnecessary pain. Allowing the cord to drain appears to shorten the third stage and reduce blood loss but evidence around this subject is not strong enough to draw solid conclusions.
Nipple stimulation and breastfeeding triggers the release of natural oxytocin in the body, therefore it is thought that encouraging the baby to suckle soon after birth may reduce the risk of PPH for the mother. A review looking into this did not find enough good research to say whether or not nipple stimulation did reduce PPH. More research is needed to answer this question.
Non-modulating essential hypertension is a form of salt-sensitive hypertension, where sodium intake does not modulate either adrenal or renal vascular responses to angiotensin II. Individuals with this subset have been termed non-modulators. They make up 25-30% of the hypertensive population.
Early detection and treatment are associated with higher rates of recovery and decreased morbidity and mortality.
Treatment for PPCM is similar to treatment for congestive heart failure. Conventional heart failure treatment includes the use of diuretics, beta blockers (B-B), and angiotensin-converting enzyme inhibitors (ACE-I) after delivery. Diuretics, preferably furosemide, help the body to get rid of excess water weight and also lower blood pressure. ACE-I and B-B improve blood circulation and contribute to the reversal of the immune system dysfunction associated with PPCM. If ACE-I is not well tolerated by the patient, it can be replaced by angiotensin receptor blockers (ARB). Hydralazine with nitrates may replace ACE-I in breastfeeding mothers or before delivery; however, evidence suggests that this course of treatment may not be as effective as ACE-I but beneficial when necessary.
If EF is less than 35%, anticoagulation is indicated, as there is a greater risk of developing left ventricular thrombi (blood clots). Sometimes implantation of a left ventricular assist device (LVAD) or even heart transplant also becomes necessary.
It is important that the patient receives regular follow-up care including frequent echocardiograms to monitor improvement or the lack thereof, particularly after changes of medical treatment regimes.
Patients who do not respond to initial treatment, defined as left ventricular EF remaining below 20% at two months or below 40% at three months with conventional treatment may merit further investigation, including cardiac magnetic resonance imaging (MRI), cardiac catheterization, and endomyocardial biopsy for special staining and for viral polymerase chain reaction (PCR) analysis. Antiviral therapy, immunoabsorption, intravenous gamma globulin, or other immunomodulation therapy may then be considered accordingly, but following a controlled research-type protocol.
Since no one knows for sure exactly when to discontinue treatment, even when recovery occurs quickly, it is still recommended that both ACE-I and B-B be continued for at least one year after diagnosis.
Some disorders and conditions can mean that pregnancy is considered high-risk (about 6-8% of pregnancies in the USA) and in extreme cases may be contraindicated. High-risk pregnancies are the main focus of doctors specialising in maternal-fetal medicine.
Serious pre-existing disorders which can reduce a woman's physical ability to survive pregnancy include a range of congenital defects (that is, conditions with which the woman herself was born, for example, those of the heart or , some of which are listed above) and diseases acquired at any time during the woman's life.
Intravenous oxytocin is the drug of choice for postpartum hemorrhage. Ergotamine may also be used.
Oxytocin helps the uterus to contract quickly and the contractions to last for longer. It is the first line treatment for PPH when its cause is the uterus not contracting well. A combination of syntocinon and ergometrine is commonly used as part of active management of the third stage of labour. This is called syntometrine. Syntocinon alone lowers the risk of PPH. Based on limited research available it is unclear whether syntocinon or syntometrine is most effective in preventing PPH but adverse effects are worse with syntometrine making syntocinon a more attractive option. Ergometrine also has to be kept cool and in a dark place so that it is safe to use. It does reduce the risk of PPH by improving the tone of the uterus when compared with no treatment however it has to be used with caution due to its effect raising blood pressure and causing worse after pains.
More research would be useful in determining the best doses of ergometrine, and syntocinon.
The difficulty using oxytocin is that it needs to be kept below a certain temperature which requires resources such as fridges which are not always available particularly in low-resourced settings. When oxytocin is not available, misoprostol can be used. Misoprostol does not need to be kept at a certain temperature and research into its effectiveness in reducing blood loss appears promising when compared with a placebo in a setting where it is not appropriate to use oxytocin. Misoprostol can cause unpleasant side effects such as very high body temperatures and shivering. Lower doses of misoprostol appear to be safer and cause less side effects.
Giving oxytocin in a solution of saline into the umbilical vein is a method of administering the drugs directly to the placental bed and uterus. However quality of evidence around this technique is poor and it is not recommended for routine use in the management of the third stage. More research is needed to ascertain whether this is an effective way of administering uterotonic drugs. As a way of treating a retained placenta, this method is not harmful but has not been shown to be effective.
Carbetocin compared with oxytocin produced a reduction in women who needed uterine massage and further uterotonic drugs for women having caesarean sections. There was no difference in rates of PPH in women having caesarean sections or women having vaginal deliveries when given carbetocin. Carbetocin appears to cause less adverse effects. More research is needed to find the cost effectiveness of using carbetocin.
Tranexamic acid, a medication to promote blood clotting, may also be used to reduce bleeding and blood transfusions in low-risk women, however evidence as of 2015 was not strong. A 2017 trial found that it decreased the risk of death from bleeding from 1.9% to 1.5% in women with postpartum bleeding. The benefit was greater when the medication was given within three hours.
In some countries, such as Japan, methylergometrine and other herbal remedies are given following the delivery of the placenta to prevent severe bleeding more than a day after the birth. However, there is not enough evidence to suggest that these methods are effective.
The most recent studies indicate that with newer conventional heart failure treatment consisting of diuretics, ACE inhibitors and beta blockers, the survival rate is very high at 98% or better, and almost all PPCM patients improve with treatment. In the United States, over 50% of PPCM patients experience complete recovery of heart function (EF 55% or greater). Almost all recovered patients are eventually able to discontinue medications with no resulting relapse and have normal life expectancy.
It is a misconception that hope for recovery depends upon improvement or recovery within the first six to 12 months of diagnosis. Many women continue to improve or recover even years after diagnosis with continued medicinal treatment. Once fully recovered, if there is no subsequent pregnancy, the possibility of relapse or recurrence of heart failure is minimal.
Subsequent pregnancy should be avoided when left ventricular function has not recovered and the EF is lower than 55%. However, many women who have fully recovered from PPCM have gone on to have successful subsequent pregnancies. A significant study reports that the risk for recurrence of heart failure in recovered PPCM patients as a result of subsequent pregnancy is approximately 21% or better. The chance of relapse may be even smaller for those with normal contractile reserve as demonstrated by stress echocardiography. In any subsequent pregnancy, careful monitoring is necessary. Where relapse occurs, conventional treatment should be resumed, including hydralazine with nitrates plus beta-blockers during pregnancy, or ACE-inhibitors plus beta-blockers following pregnancy.