Indiana University - Purdue University, Fort Wayne. Z. Tragak, MD: "Buy Nebivolol online no RX - Quality Nebivolol online OTC".
Rubeola (measles) Oral vitamin A therapy decreases mortality and improves recovery from pneumonia in children [58 purchase cheapest nebivolol heart attack death,59] purchase genuine nebivolol on line arrhythmia tutorial. Shiraishi K purchase nebivolol cheap online prehypertension young, Mitamura K safe nebivolol 2.5mg heart attack clothing, Sakai-Tagawa Y, et al: High frequency of resistant viruses harboring different mutations in amantadine-treated children with influenza. Puhakka T, Lehti H, Vainionpaa R, et al: Zanamivir: a significant reduction in viral load during treatment in military conscripts with influenza. Kaiser L, Wat C, Mills T, et al: Impact of oseltamivir treatment on influenza-related lower respiratory tract complications and hospitalizations. Jefferson T, Jones M, Doshi P, et al: Neuraminidase inhibitors for preventing and treating influenza in healthy adults: systematic review and meta-analysis. Kiso M, Mitamura K, Sakai-Tagawa Y, et al: Resistant influenza A viruses in children treated with oseltamivir: descriptive study. South East Asia Infectious Disease Clinical Research Network: Effect of double dose oseltamivir on clinical and virological outcomes in children and adults admitted to hospital with severe influenza: double blind randomised controlled trial. Ribaud P, Scieux C, Freymuth F, et al: Successful treatment of adenovirus disease with intravenous cidofovir in an unrelated stem-cell transplant recipient. Tatsukawa M, Sawayama Y, Nabeshima S, et al: A case of severe adult measles pneumonia—efficacy of combination of steroid pulse therapy, high-dose vitamin A and gamma globulins. Chotpitayasunondh T, Ungchusak K, Hanshaoworakul W, et al: Human disease from influenza A (H5N1), Thailand, 2004. The virion is enveloped with cellular membrane and is formed of the virus-encoded structural proteins, of which spike (S) protein is the main attachment factor responsible for entry of the virion into the host cell . The first confirmed case was in November 2002, after which it spread around the world to 26 countries, causing 8,096 confirmed cases and 774 deaths (a case fatality rate of 9. There is also evidence that dromedary camels (Camelus dromedaries) act as an intermediate between bats and humans [17,18]. Camels are an extremely important species in the Middle East, where they are a source of meat, fabric, and milk, and camel racing is an important part of the cultural and economic development in the region. There is also evidence of edema and the alveolar septa were thickened with lymphocytes (but not plasma cells), neutrophils, and macrophages . Gender, specifically being male, is excluded from the table, as this factor has been specifically identified with access to dromedary camels [36,39]. It is also important to establish a clear infection control plan for use in the hospital setting, including rapid diagnostic and safety protocols . Korea Centers for Disease Control and Prevention: Middle East Respiratory Syndrome Coronavirus Outbreak in the Republic of Korea, 2015. Hauser G, Awad T, Brok J, et al: Peginterferon plus ribavirin versus interferon plus ribavirin for chronic hepatitis C. The size and worldwide nature of this outbreak demonstrates that health care facilities require protocols for the care of patients who might be or are definitively harboring Biosafety Level 4 agents such as Ebola. The following chapter will review special considerations for the diagnosis and care of patients with Ebola virus infection. Given its similar taxonomy and clinical features, the principles discussed here almost certainly apply in like manner to patients suffering from Marburg virus disease, which since its original episode in Germany has not been observed outside of sub-Saharan Africa, but is equally likely to present off the African continent given the ease and increase of international travel. The transmission of Ebola primarily takes place by direct contact with body fluids, where virions enter into the host via mucous membranes or skin breaks . Incubation of the virus typically lasts between 2 and 21 days; most cases present in the second week following exposure . The relatively long incubation times coupled with highly efficient transcontinental travel underscores the importance of heightened surveillance and the need for health care facilities everywhere to have response plans in place. Therefore, patients from Ebola-endemic countries presenting with circulatory collapse in the setting of a febrile illness may require rapid isolation and testing for Ebola and Marburg. This, in turn, may lead to gut translocation of gram-negative organisms, potentially leading to bacterial sepsis as a major cause of mortality . Other common early symptoms include fatigue, arthralgias and myalgias, anorexia, headache, and abdominal pain. A diffuse, erythematous nonpruritic maculopapular rash was only rarely reported in the West African Outbreak, although it appeared to have been more prevalent among the whites who became infected and thus may have been underdiagnosed in Africans with darker skin . If the patient is no longer symptomatic after 72 hours, repeat testing is not required; however, patients with ongoing symptoms must be retested. Potassium regulation can be difficult, as one study indicated that equal numbers of patients developed hypo- or hyperkalemia . Hiccups may also be seen and should prompt suspicion in the setting of other appropriate epidemiologic clues . Coupled with insensible losses from fevers, the significant fluid depletion often leads to circulatory collapse and likely accounts at least in part for the high mortality of the disease. The prevalence of bleeding of any kind before the West African Outbreak was reported to be in the range of approximately 50%; during the West African Outbreak, at least one study reported a prevalence of less than 20% . Studies in previous outbreaks indicated that, although less common, hemorrhage was typically associated with a worse prognosis . Similarly, mental status changes such as encephalopathy probably reflects end-organ damage and carries a high mortality. While many patients experience rapid improvement, they remain viremic for as long as 21 days or more . Therefore, provisions need to be made for convalescing patients who must remain in isolation during this time, and psychosocial needs may outweigh physiologic considerations, as survivors commonly cope with fear, grief, and anxiety about the social stigma that may await them following discharge . Following discharge, patients experience a range of complications that can be debilitating and last for months or even years. The persistence of Ebola virus in immunologically privileged “sanctuary” sites, such as semen  and ocular fluid , indicates that special precautions must be taken when evaluating survivors in routine follow-up care, with Biosafety Level 4 protocols being used in the event that providers might be exposed to fluids from these viral reservoirs. In critical care settings, the need for safety protocols is even greater due to the larger number of opportunities for occupational exposure. Donning and doffing should always take place in a single decontamination area that is clearly demarcated. Only staff involved in entering or leaving the high-risk area, or those who are supervising such workers, should be allowed in such areas. Owing to the multistep nature of the donning and doffing procedures, the protocol should be simulated multiple times by the staff. Special care should be given to evaluation of the face if goggles are being worn on top of a hood instead of a single headpiece, as the corners of the mask may not overlap. If the worker “gets lost” in the multistep process, the supervisor/observer should always spray the worker down with a bleach solution before proceeding to the next step. The latter, while more expensive, have the advantages of not requiring fit testing and may provide better protection in the event of splashes. Because commonly tested body fluids used in clinical specimens should be regarded as highly infectious and require at least as much care with respect to decontamination as health care workers, testing should be minimized to the greatest extent possible. Point-of-care testing, when possible, should be utilized, particularly as clinical Ebola management involves monitoring and adjusting standard laboratory parameters, especially sodium and potassium, for which point-of-care products are generally found with ease. At present, multiple candidate vaccines have been studied, although no definitive results with respect to vaccine efficacy have been established at the time of this writing .
Plasma creatine kinase levels should be determined in patients with muscle complaints nebivolol 5 mg free shipping blood pressure chart to keep track. These drugs are contraindicated during pregnancy buy 2.5mg nebivolol fast delivery jon gomm hypertension zip, lactation buy cheap nebivolol 5 mg on-line arteria ulnar, and active liver disease generic nebivolol 2.5 mg online pulse pressure femoral artery. Niacin can be used in combination with statins, and fixed-dose combinations of long-acting niacin with lovastatin and simvastatin are available. Mechanism of action At gram doses, niacin strongly inhibits lipolysis in adipose tissue, thereby reducing production of free fatty acids (ure 22. The liver normally uses circulating free fatty acids as a major precursor for triglyceride synthesis. Therapeutic uses Because niacin lowers plasma levels of both cholesterol and triglycerides, it is useful in the treatment of familial 838 hyperlipidemias. It is also used to treat other severe hypercholesterolemias, often in combination with other agents. Adverse effects the most common adverse effects of niacin are an intense cutaneous flush accompanied by an uncomfortable feeling of warmth and pruritus. Administration of aspirin prior to taking niacin decreases the flush, which is prostaglandin-mediated. Slow titration of the dosage or use of the sustained-release formulation of niacin reduces bothersome initial adverse effects. Niacin inhibits tubular secretion of uric acid and, thus, predisposes patients to hyperuricemia and gout. The drug should be avoided in active hepatic disease or in patients with an active peptic ulcer. They then bind to peroxisome proliferator response elements, which ultimately leads to decreased triglyceride concentrations through increased expression of lipoprotein lipase (ure 22. Pharmacokinetics Gemfibrozil and fenofibrate are completely absorbed after oral administration and distribute widely, bound to albumin. Fenofibrate is a prodrug, which is converted to the active moiety fenofibric acid. Both drugs undergo extensive biotransformation and are excreted in the urine as glucuronide conjugates. Because these drugs increase biliary cholesterol excretion, there is a predisposition to form gallstones. Myositis (inflammation of a voluntary muscle) can occur, and muscle weakness or tenderness should be evaluated. Myopathy and rhabdomyolysis have been reported in patients taking gemfibrozil and statins together. The use of gemfibrozil is contraindicated with simvastatin, and, in general, the use of gemfibrozil with any statin should be avoided. Fibrates should not be used in patients with severe hepatic or renal dysfunction, in patients with preexisting gallbladder disease or biliary cirrhosis. The resin/bile acid complex is excreted in the feces, thus lowering the bile acid concentration. This causes hepatocytes to increase conversion of cholesterol to bile acids, which are essential components of the bile. Colesevelam is also indicated for type 2 diabetes due to its glucose-lowering effects. Pharmacokinetics Bile acid sequestrants are insoluble in water and have large molecular weights. After oral administration, they are neither absorbed nor metabolically altered by the intestine. These agents may impair the absorption of the fat-soluble vitamins (A, D, E, and K), and they interfere with the absorption of many drugs (for example, digoxin, warfarin, and thyroid hormone). Therefore, other drugs should be taken at least 1 to 2 hours before, or 4 to 6 hours after, the bile acid sequestrants. These agents may raise triglyceride levels and are contraindicated in patients with significant hypertriglyceridemia (greater than 400 mg/dL). This causes a reduction of hepatic cholesterol stores and an increase in clearance of cholesterol from the blood. Ezetimibe is primarily metabolized in the small intestine and liver via glucuronide conjugation, with subsequent biliary and renal excretion. Patients with moderate to severe hepatic insufficiency should not be treated with ezetimibe. Monoclonal antibodies are not eliminated by the kidneys and have been used in dialysis patients or those with severe renal impairment. The most common adverse drug reactions are injection site reactions, immunologic or allergic reactions, nasopharyngitis, and upper respiratory tract infections. Bleeding risk can be increased in those who are concomitantly taking anticoagulants or antiplatelet agents. Combination drug therapy It is sometimes necessary to use two antihyperlipidemic drugs to achieve treatment goals. Liver and muscle toxicity occur more frequently with lipid-lowering drug combinations. Gastrointestinal disturbances frequently occur as an adverse effect of antihyperlipidemic drug therapy. Cholestyramine lowers the amount of bile acids returning to the liver via the enterohepatic circulation. Cholestyramine is an anion-exchange resin that binds negatively charged bile acids and bile salts in the small intestine. The resin/bile acid complex is excreted in the feces, thus preventing the bile acids from returning to the liver by the enterohepatic circulation. What advice would you give this patient to avoid a drug interaction between her cholestyramine and levothyroxine? Cholestyramine and the bile acid sequestrants can bind several medications, causing decreased absorption of medications such as levothyroxine. Administration of levothyroxine 1 hour before or 4 to 6 hours after cholestyramine can help to avoid this interaction. Choices C and D are incorrect, as all bile acid sequestrants cause this interaction. He reports uncomfortable flushing and itchiness that he thinks is related to the niacin. Flushing associated with niacin is prostaglandin mediated; therefore, use of aspirin (a prostaglandin inhibitor) can help to minimize this adverse effect. It must be administered 30 minutes before the dose of the niacin; therefore, choice B is incorrect. Increasing the dose of niacin is likely to increase these complaints; therefore, choice C is incorrect.
Spanish Chestnut (Horse Chestnut). Nebivolol.
- Pain, tiredness, tension, swelling in the legs, itching, and water retention (edema).
- Hemorrhoids, diarrhea, fever, cough, enlarged prostate, eczema, menstrual pain, soft tissue swelling from bone fracture and sprains, arthritis, rheumatism, and other conditions.
- Dosing considerations for Horse Chestnut.
- Are there any interactions with medications?
- Varicose veins and other circulatory problems (chronic venous insufficiency).
- What is Horse Chestnut?
- How does Horse Chestnut work?
- What other names is Horse Chestnut known by?
- Are there safety concerns?
This success impressed the two men nebivolol 2.5mg for sale hypertension kidney failure, especially Hoagland order nebivolol with a mastercard arrhythmia nausea, planting the idea that it would be possible to support research with private money purchase nebivolol us blood pressure ranges uk. In 1933 cheap 5mg nebivolol otc blood pressure 80 over 40, he earned a bachelor’s degree in animal psychology from the Tsing Hua University in Peking and stayed at the university as a teacher. Afer 1 year, he was pleased to receive an invitation from Arthur Walton to study the physi- ology of sheep sperm at The University of Cambridge, and he promptly accepted. He wrote three letters to American scientists, and only Pin- cus answered, ofering a fellowship at Clark University. Chang mistakenly assumed that a fellowship in the United States was the same as at the Uni- versity of Cambridge where a Fellow was assured of a lifetime income. Years later, Chang would direct the testing of new progestins to efectively inhibit ovulation in animals. Soon Hoagland had put together a group of outstanding scientists, but because of his ongoing antagonism with President Atwood, the group was denied faculty status. A Clinical Guide for Contraception Frustrated by the politics of academia, Hoagland and Pincus (who both enjoyed stepping outside of convention) had a vision of a private research center devoted to their philosophy of applied science. Indeed, the establish- ment of the Worcester Foundation for Experimental Biology, in 1944, can be attributed directly to Hoagland and Pincus, their friendship for each other, and their confdence, enthusiasm, ambition, and drive. It was their spirit that turned many members of Worcester society into fnancial supporters of biologic science. Tey created and sustained a vibrant, productive scientifc institution in which it was a pleasure to work. Although named the Worcester Foundation for Experimental Biology, the Foundation was located in the summer of 1945 across Lake Quinsiga- mond in a house on an estate in Shrewsbury. From 1945 to the death of Pincus in 1967, the staf grew from 12 to 350 (scientists and support people), 36 of whom were independently funded and 45 were postdoctoral fellows. Katharine Dexter McCormick (1875–1967) was a trained biologist, an early sufragist, and rich, inheriting millions from her mother and a McCormick fortune from her husband. She was the second woman to graduate from the Massachusetts Institute of Technology, socially conscious, and a generous contributor to family planning eforts. Her intervention with money, energy, incisive thinking, and persistent dedication was instrumental in the develop- ment of oral contraception. In 1904, she married Stanley McCormick, the son of Cyrus McCormick, the founder of International Harvester. Katharine’s husband sufered from schizophrenia, and she established the Neuroendo- crine Research Foundation at Harvard to study schizophrenia. This brought her together with Hoagland, who told her of the work being done by Chang and Pincus who were seeking orally active progestins to inhibit ovulation. Pincus attributed his interest in contraception to his growing apprecia- tion for the world’s population problem, and to a 1951 visit in New York with Margaret Sanger, at that time president of the Planned Parenthood Federation of America. Sanger promised a small amount of money and expressed hope that a method of contraception could be derived from the laboratory work being done by Pincus and Chang. He envisioned a progestational agent in pill form as a contraceptive, acting like progesterone in pregnancy. On June 7, 1953, when 78-year-old Katharine met with 50-old Pincus at the Worcester Foundation and wrote him a check for $20,000; she promised him Oral Contraception another $20,000. Pincus received a second check for $20,000, and Katharine agreed to fund laboratory improvements, which ended up as the completion of a new building in 1955. Katharine’s contract with the Worcester Foundation stipulated that Pincus would provide written reports every 2 weeks. In addition, Pincus and John Rock, the Boston gynecologist performing the initial oral contraceptive studies in his patients, made many visits to Katharine’s home ofce on Beacon Street across the street from the Harvard Club. Katharine had Sara De Laney, her secretary, take careful notes in shorthand, and at the next visit De Laney read the tran- scribed notes to her boss so that she would be prepared. She found Pincus “imaginative and inspirational; Rock was informative and very realistic about medical work. She had earned their respect, and detailed reports on laboratory results, clinical planning, and budgets were immediately forthcoming. Time and time again, Katharine proved that she handled delays poorly, but she approached each meeting with an eagerness that slowly but surely was rewarded with success afer 7 years and an expenditure of about $2 million of Katharine’s money. When testing the hundreds of compounds that yielded the progesta- tional agents in birth control pills, Chang observed that some of them prevented implantation of fertilized eggs in rabbits. From 1962 to 1966, Chang and Pincus were pursuing a drug that could prevent pregnancy with one administration, a day or two afer sexual intercourse. It is not certain whether Chang and Pincus coined the phrase the “morn- ing afer” pill, but it is accurate to state that the concept came from Chang. When Pincus and Chang began their studies, the focus was on inhibition of ovulation, frst by progesterone, and then by synthetic progestins. Chang worked away in his laboratory, and it was Pincus who was highly visible, raising the money and providing direction. Chang started by repeating the experiments reported by Make- peace in 1927, documenting that progesterone could inhibit ovulation. By December 1953, three synthetic progestins were selected as the most potent and efective in inhibiting ovulation: norethindrone from Syntex, and Searle’s norethynodrel and norethandrolone. It was Pincus who made the decision to involve a physician because he knew human experiments would be necessary. John Rock, chief of gynecology and obstetrics at Harvard, met Pincus at a scientifc conference A Clinical Guide for Contraception and discovered their mutual interest in reproductive physiology. Using oocytes from oophorectomies, they reported in vitro fertilization in 1944, the frst demonstration of fer- tilization of human oocytes in vitro. Rock was interested in the work with progestational agents, not for contraception, however, but because he hoped the female sex steroids could be used to overcome infertility. Not one became pregnant during treatment, pleasing Pincus who all along was aiming for contraception, and four became pregnant afer treatment, pleasing Rock who initially was motivated by his pursuit of the “rebound” phenomenon for the treatment of infertility. Sanger and McCormick needed some convincing that Rock’s Catholicism would not be a handicap, but they were eventually won over because of his stature. Rock was a physician who literally transformed his personal values in response to his recognition of the problems secondary to uncontrolled reproduction. With the help of Luigi Mastroianni, the frst administration of synthetic progestins to women was to Rock’s patients in 1954. Of the frst 50 patients to receive 10 to 40 mg of synthetic progestin (a dose extrapolated from the animal data) for 20 days each month, all failed to ovulate during treatment (causing Pincus to begin referring to the medication as “the pill”), and 7 of the 50 became pregnant afer discontinuing the medication, again pleasing Rock, who all along was motivated to treat his infertile patients. In 1956, with Celso-Ramon Garcia and Edris Rice-Wray, working in Puerto Rico, the frst human trial was performed. In the amounts being used, this added up to 50 to 500 mg of mestranol, a sufcient amount of estrogen to inhibit ovulation by itself. When eforts to provide a more pure progestin lowered the estrogen content and yielded breakthrough bleeding, it was decided to retain the estrogen for cycle control, thus establishing the principle of the combined estrogen-progestin oral contraceptive.
Families such pregnancies using cerebral nebivolol 2.5 mg online arteria obturatriz, peripheral and intracar‑ of women who give birth to babies after a multiple preg‑ diac arterial and venous Doppler velocimetry is required order nebivolol line heart attack risk assessment. For example generic nebivolol 5 mg on-line blood pressure medication and hair loss, cessation of fetal growth with pre‐terminal arterial and venous Doppler studies may warrant deliv‑ ery at 26 weeks in a singleton fetus discount nebivolol 2.5 mg with amex heart attack demi lovato sam tsui chrissy costanza of atc. In addition, abdominal palpation and in concert with parents and multidisciplinary teams symphysis–fundal height measurement are unreliable as (including neonatologists). There is some evidence that the presence or There is no proven agreement on the ideal frequency absence of umbilical artery Doppler flow during diastole of ultrasound examination. Positive end‐diastolic veloci‑ icy to scan dichorionic twins at up to 4‐weekly intervals ties indicate the best prognostic group when there is from 24 weeks’ gestation with or without Doppler meas‑ significant discordancy between monochorionic twins urements as indicated. In some cases (of early onset) it may be ture (1436 pregnancies) has indicated the potential necessary to consider selective cord occlusion rather efficacy of cervical length in predicting risk of spontane‑ than delivery of the whole pregnancy (depending on the ous preterm delivery in twins. However, these again are gestation, the mean maternal cervical length is similar to difficult decisions evoking clinical complexity and paren‑ that of singleton pregnancies (38 mm). Management in a tertiary centre is therefore a cervical length of 25mm or less will have a positive vital and individual discussions relating to procedure‐ summary likelihood ratio of 5. This correlates with a change from pretest probability of preterm birth Preterm labour of 18. Recent data indicate that, overall, the use of home uterine activity monitoring or fetal 52. This is the major cause of conclusively to be useful in prediction and therefore can‑ neonatal death in multiple pregnancies: mortality rates not be advocated. The median gestational ages at delivery in twins and Preterm labour in a multiple pregnancy (as in polyhy‑ triplets is 37 and 34 weeks, respectively. However, the dramnios) is attributed to over‐distension (‘stretch’) of proportion of these pregnancies delivering before 30 the uterus. Accordingly, there is no specific preventive weeks (twins 7%, triplets 15%) is much more concerning measure (aside from fetal reduction in higher‐order mul‑ because of the associated long‐term morbidity. Certainly (as in polyhydramnios) there is of four randomized controlled trials indicate that bed rest increased uterine distension (i. There is also focus on the potential maternal–fetal In contrast, a single randomized controlled trial in triplets endocrine interaction, which may predispose to this demonstrated a non‐significant trend to less premature increased risk. Management of preterm labour in multiple lack of efficacy in singleton pregnancies and is presuma‑ pregnancies differs little from that of singletons, except bly due to tachyphylaxis. As in singleton pregnancies, this that the consequences of prematurity affect a greater therapy is no longer used. The following discussion concentrates and most recently vaginal progesterone therapy, has not on those aspects which appertain especially to multiple been shown to be helpful and indeed may actually be pregnancies. Indeed, an individual patient‐level meta‐ analysis of randomized trials of cervical cerclage in women with a ‘short’ cervix (on ultrasound at 20–23 Prediction weeks) indicated an increased risk of preterm delivery the prediction of preterm labour in twins and multiple prior to 35 weeks . Most contemporary focus has fallen on the role of One of the most promising methods of prediction of maternal administration of progesterone in potentially 274 Fetal Medicine reducing the risk of preterm delivery. The Study Of to antepartum haemorrhage and 7% associated with one Progesterone for the Prevention of Preterm Birth In or more fetal deaths. However, only one the composite outcome risk of delivery or intrauterine uncontrolled study with separate data from multiple death before 34 weeks in women with twin pregnancy. Such findings are in concordance ‘resistance’ of multiple pregnancies to pulmonary sur‑ with other studies demonstrating no efficacy [34,35], factant maturation compared with singleton pregnancies in which progesterone was administered as intra‑ has been postulated and has raised the possibility that a muscular 17‐hydroxyprogesterone caproate (250mg). It has therefore been proposed that corticosteroids Recently, there has been interest as to whether physical be administered prophylactically. Such a proposal is con‑ interventions, such as the fitting of an Arabin cervical troversial. It is certainly theoretically possible that this pessary, reduces the risk of preterm birth in twin preg‑ could do more harm than good, as such therapy would nancies with a short cervix (<25mm). A recent study, potentially need to be administered on a weekly basis performed under the collaborative umbrella of the Fetal and there is no evidence that repeat doses of steroids are Medicine Foundation found no significant improvement of increased value. Furthermore, and not withstanding in the risks of preterm birth in the intervention group the safety of steroids in follow‐up studies, there remain (compared to the conservative group). Complications of monochorionic Management twinning the use of β2‐sympathomimetic infusions in multiple pregnancy, along with steroids and fluid overload, are Monochorionic twinning, which complicates 20% of all known risk factors for the rare but potentially fatal com‑ twin pregnancies, may be said to be a congenital anomaly plication of pulmonary oedema. As in singleton of the placenta where the inter‐twin circulations commu‑ pregnancies, such active tocolysis has all but been aban‑ nicate through placental vascular anastomoses. Equally, tocolysis with maternally administered occur in almost all monochorionic twin pregnancies. Relatively small inter‐twin singleton pregnancies, the use of such therapy is usually ‘transfusions’ are thus likely to be a normal physiological only advocated to allow prophylaxis with corticoster‑ event in monochorionic twins. This is exemplified in a retrospective cohort study of flow between twins may well be pathological and is of 432 twin pregnancies (1982–1986), which noted that always a potential risk in such pregnancies (increasing 54% of twins were born after spontaneous preterm perinatal mortality considerably). Such a vicious circle of events leads to the there are reports of damage to pulmonary and hepatic ‘donor’ twin becoming hypoperfused, growth restricted systems, intestinal atresia, limb reduction and renal and with associated oliguria and the development of necrosis. Death of one of a mono‑ dynamic circulation that may cause both diastolic and chorionic twin substantially increases the risk of co‐twin systolic cardiac dysfunction, ending in the development demise in utero. Again, a recent systematic review has of hydrops fetalis and death (if no treatment ensues). A staging system has been described intrauterine fetal death influences the extent and type and is useful in annotating the condition in a consistent of fetal brain injury. Single intrauterine fetal death manner but does not always denote a logical order of dis‑ after the second trimester can lead to periventricular ease progression (Table 21. The principal clinical problem is severe Unlike dichorionic twins, discordant fetal compromise polyhydramnios, which may be associated with prema‑ with risks of intrauterine demise in one twin have to be ture rupture of membranes or preterm labour (or a balanced against the potentially adverse effects of iatro‑ combination of these) usually before 26 weeks’ gestation. Fetoscopic laser ablation/ prevent intrauterine death in the potentially compro‑ coagulation of the inter‐twin communicating vessels mised twin but also to prevent sequelae in the co‐twin. The pregnancy should be evaluated for onic twin pregnancies presenting with this complication secondary sequelae, initially by the use of ultrasound. It appears that the main miniscule arteriovenous anastomoses (<1mm) which neonatal morbidity consists of anaemia (requiring trans‑ allow slow transfusion of blood from the donor to the fusion) and polycythaemia (possibly requiring partial recipient, leading to highly discordant haemoglobin con‑ exchange transfusion). The criteria for diagnosis include a differ‑ delay is increased (20%) Therefore, brain imaging during ence in haemoglobin concentration between the twins of the third trimester and neurodevelopmental assessment more than 80g/L and reticulocyte count ratio greater at the age of 2 years are recommended. Twin reversed arterial perfusion sequence This rare condition (complicating 1 in 35 000 pregnan‑ cies) arises in monochorionic twins with two umbilical cords often linked by large arterio‐arterial anastomoses. Flow from one, the ‘pump’ twin, supplies the other, the ‘perfused’ twin, in a retrograde fashion. The perfused twin almost always has associated significant congeni‑ tal malformations, often including a rudimentary heart and aorta. Thus the acardiac twin is perfused by its co‐twin (the pump twin) via the inter‐ twin placental anastomoses. There is still controversy plicated by placental anomalies associated with increased whether to offer intervention electively, or only when perinatal mortality (i. With careful case gestation in twins and there are therefore many obste‑ selection improved outcome for the pump twin is tricians who elect for delivery then. Most significant com‑ no data to indicate whether or not this rise in mortality plications include co‐twin demise or hypoperfusion applies to twins whose growth and well‐being are (with cerebral morbidity) and/or preterm ruptured known to be normal on ultrasound. Mode of delivery is decided on standard principles based on presentation of the first twin (cephalic in 70%, breech in Monoamniotic twins 30%) and the documentation of optimal fetal growth Of monozygotic twins, 1% lie in the same sac and well‐being.