X
|
STUDENT DIGITAL NEWSLETTER ALAGAPPA INSTITUTIONS |
|
Mouaz H. Al-Mallah, MD, MSc, FACC, FAHA, FESC
Law and Regulation for a Broadband World 111 Regulating Bottlenecks in the Broadband Supply Chain Supplying broadband services involves a combination of network elements arrhythmia recognition course generic aldactone 100 mg, processing hypertension va disability aldactone 25mg with amex, and business services that can be thought of as the broadband supply chain ulterior motive synonym buy generic aldactone 100mg. More fully described in chapter 5 blood pressure chart hospital generic aldactone 25mg, this supply chain can be divided into four main components: (a) international connectivity blood pressure keeps rising generic aldactone 25 mg online, (b) domestic backbone heart attack quiz buy 100mg aldactone overnight delivery, (c) metropolitan connectivity, and (d) local connectivity. Bottlenecks in any of the links of the chain will stifle competition and the development of broadband. Hence, effective regulatory frameworks must identify and address such instances of market failure in a timely and effective manner. International Connectivity As electronic communications traffic-particularly Internet traffic-enters and leaves a country, it is typically routed through one or more international facilities, including submarine cables, cable landing stations, and international gateways. As the adoption of broadband services and applications increases, demand for international bandwidth also rises. Between 2002 and 2009, international bandwidth usage increased by 60 percent a year, with the strongest demand growth taking place on links to Africa, Latin America, and Middle Eastern countries, which experienced annual growth rates of over 74 percent during this period. The most efficient way to lower costs and keep pace with demand is through liberalization and promotion of competition among facilities that provide international connectivity, in particular, international gateways, submarine cables, and landing stations. As such, it is important to ensure that there is more than one international carrier and international gateway and, where possible, that there are redundant international cables and other facilities linking a country to competitive global communication networks. For example, Nigeria supported facilities-based competition in the international connectivity market through the introduction of a unified access service license in 2006, which allowed licensees to "construct, maintain, operate, and use an international gateway" and networks consisting of any type of technology, including wireless or wireline systems (Singh and Raja 2010, 58). Facilities-based competition in the international connectivity markets may not be feasible in all developing countries, especially those that generate small amounts of traffic. For countries without a well-functioning international connectivity market, targeted ex ante regulation may be required to address market failure (Hernandez, Leza, and Ballot-Lena 2010). This determination was based on an expected increase in facilitiesbased competition by 2012, stemming from the landing of four additional submarine cables, one of which is to be operated on an open-access basis. During this time, competing providers added only limited extra capacity of their own, mostly via satellite links and limited terrestrial links. At the time of the market analysis, four new submarine cables were scheduled to commence service in Nigeria: two in 2010 (Globacom-1 and Main One) and two more within the next two years (the West Africa Cable System in 2011 and the Africa Coast to Europe in 2012). Law and Regulation for a Broadband World 113 example, after conducting a review of wholesale inputs for broadband Internet access, the regulator found that cable landing stations constituted essential facilities and required landing station operators to provide access to their facilities on nondiscriminatory terms and to publish a reference access offer. A major impediment to reducing these costs, particularly in many developing countries, relates to vertical integration in which the backbone network providers are vertically integrated with the local access network operators. As such, other service providers may not have access to the backbone or may face high costs for interconnecting, a problem addressed in growing debates on open network access. From a regulatory perspective, the first step toward facilitating competition in vertically integrated networks is to ensure a liberalized market. The second step toward increasing competition may entail targeted, ex ante regulations requiring the backbone network provider to offer network capacity on a wholesale, open-access, and nondiscriminatory basis to downstream providers. Alternatively, some countries are setting up national backbone operators that only provide wholesale broadband services on an open-access basis in order to prevent any vertical integration. This scheme is being 114 Broadband Strategies Handbook implemented or proposed in countries such as Australia, Brazil, Colombia, Singapore, and South Africa. However, public financing of national backbones should not crowd out private investment or distort competition. Moreover, where a public subsidy is provided to a backbone broadband network, open-access obligations should be imposed. Cross-sector coordination is also relevant to the efficient deployment of national connectivity. Fiber optic networks are usually built along existing infrastructure networks such as roads, railways, pipelines, or electricity transmission lines. Most of the cost of constructing fiber optic cable networks along these alternative infrastructure networks lies in the civil works. These costs represent a major fixed and sunk investment, increasing the risks faced by network operators. By lowering the cost of access to these infrastructure networks and reducing the risk associated with it, governments can significantly increase incentives for private investment in backbone networks. One way to reduce costs is to make rights-of-way readily available to network developers by simplifying the legal process and limiting the fees that can be charged by local authorities. Additionally, governments can provide direct access to existing infrastructure that they own or control. For example, a railway company could partner with one or more operators to build a fiber optic cable network along the railway lines. Competitive and well-functioning wholesale markets for backhaul capacity (for example, leased lines) are a critical component of broadband diffusion and adoption. Developing countries are beginning to focus on core backbone and backhaul networks as a means to increase broadband deployment. For example, South Africa established a state-owned fiber-based infrastructure provider, Broadband Infraco, to provide national backhaul connections on a wholesale basis. Law and Regulation for a Broadband World 115 Particularly for rural and remote areas, wireless technologies may be the most practical solution for high-capacity backhaul for mobile broadband. Local Connectivity Local access networks, also called the "last mile," refer to the links between the local switch and the consumer. This last link in the broadband supply chain has garnered much attention in recent years, as countries seek to expand service into unserved or underserved areas and to promote competition between operators at the retail level. Unlike other parts of the supply chain, local access regulation can be divided into two distinct areas of policy based on technology: wireline and wireless. Although the goals of policy makers are the same in each case-expand network availability and promote competition-the approaches must be tailored to the unique opportunities and constraints entailed in each technology. For many years, it was assumed that the local loop services were a "natural monopoly" because they tend to be the most difficult and costly part of the network for alternative operators to replicate. However, as cable networks and commercial wireless services began competing with traditional telecommunications operators, policy makers began reexamining the possibility of facilities-based competition or otherwise promoting service-based competition in the local loop. The degree and extent of regulatory intervention in access networks, particularly on the wireline side, depend on the legacy endowment of infrastructure of each country. However, in developing countries without significant wireline (broadband) infrastructure at the local level, such obligations may have limited impact. The main disadvantage is that it can be a disincentive to fresh infrastructure investment by the incumbent operator (for instance, in deployment of a fiber optic network), especially in developing countries where the local loop is not yet fully built out. Several countries, including the Netherlands, Sweden, and Slovenia, have proposed or implemented fiber unbundling policies. One reason is that the base of installed wireline telephone lines is generally much lower in developing than in developed nations. Commercial wireless networks have been an important local access technology for more than a decade and have become the predominant means of providing local access to voice and now broadband services in many developing countries. Wireless networks can help to overcome the last-mile wireline bottleneck by giving consumers multiple options for broadband access. For governments seeking to promote greater broadband connectivity, wireless offers some notable advantages, such as a Law and Regulation for a Broadband World 117 lower cost structure in rural areas and faster rollout, since it is easier to deploy a series of cell towers than to connect each household with a physical wire. With the introduction of 3G and 4G technologies, wireless networks are expected to compete directly with, and be substitutes for, wireline broadband within the next decade. To support the expected increase in demand for advanced services requiring faster download speeds and the greater use of such services, regulators are implementing policies that promote the most efficient and effective use of spectrum resources, including freeing up spectrum bands that are either unused or underutilized. Another major tool for promoting wireless broadband development is for governments to allow flexible use of spectrum so as not to constrain technology or service developments. Technology neutrality refers to the concept that operators should be allowed to use whatever technology or equipment standard they wish in order to meet market demands. Thus, rather than having regulators mandate that a specific technology must be used in a certain band, operators are allowed to choose whatever technology they wish, subject to technical limitations-to prevent interference, for example. With the transition to digital technology and better processing capabilities, advanced systems are now capable of transmitting all kinds of services. Wireless operators can now provide voice, high-speed data services, and video over their networks. Government regulators should modify service and licensing terms to allow operators to realize the benefits of this flexibility. The move to market mechanisms can be seen in two important trends: assigning spectrum to operators using some sort of competitive mechanism (for example, auctions) and charging market-based prices for acquiring or using spectrum. Having a competitive, transparent means of assignment can also give service providers greater access to spectrum. In conjunction with a regime that allows 118 Broadband Strategies Handbook flexible use of spectrum, such competitive assignment can enable new models of service provision. Once spectrum has been assigned, spectrum trading (secondary market license transfers) allows later entrants to a market to access spectrum by paying a market price for it. This improves competition by allowing companies who want (new or additional) spectrum to acquire it from those who may have excess spectrum in specific areas. Governments can promote wireless broadband availability by establishing coverage obligations at the time of initial licensing. License requirements tied to coverage obligations, however, must be carefully considered. Requirements that are too easy to meet run the risk of not significantly expanding broadband coverage. Conversely, overly strict requirements are unlikely to be met and could result in either no interest in a license or lower payments. Infrastructure Sharing As governments seek ways to expand broadband networks and promote competition in broadband services, they inevitably encounter difficulties. In some areas, low population densities may make it unlikely that the market will support multiple competing wireline or wireless infrastructures. In addition, for some buildings in urban areas, there may not be sufficient physical space to run multiple sets of fiber or copper cables to each potential user or to place wireless towers and other equipment. In such cases, policy makers and regulators have begun to encourage-or even require-parties to share the physical infrastructure used to deliver broadband services. Infrastructure sharing can take many forms, with the most common being collocation (the sharing of Law and Regulation for a Broadband World 119 physical space in buildings), tower and radio access network sharing, access to dark fiber for backhaul, and backbone networks and physical infrastructure sharing (ducts and conduits). Infrastructure sharing is rapidly becoming an important means of promoting universal access to networks and offering affordable broadband services by reducing capital expenditures and ongoing operating expenses associated with the rollout and operation of networks. In recent years, a noticeable trend has been toward voluntary sharing of active and passive network facilities around the world, especially in the mobile sector. A push to upgrade and expand networks for mobile broadband is resulting in service providers searching for ways to cut costs and raise capital. For example, service providers may create joint ventures that manage the combined infrastructure assets either for shared use by its owners or on an openaccess basis. This allows for network optimization and for avoidance or decommissioning of redundant sites, leading to significant cost reductions for the parties involved. The joint venture in the United Kingdom between Hutchison 3G and T-Mobile, now joined by Orange after its merger with T-Mobile in the United Kingdom, and the pan-European agreement between O2 and Vodafone to share infrastructure in Germany, Spain, Ireland, and the United Kingdom highlight this trend toward increased voluntary sharing in the sector. Since then, Bharti Group, Vodafone Group, and Aditya Birla Telecom (Idea Cellular) have created Indus Tower, a joint venture that controls over 100,000 towers and provides passive infrastructure service to its shareholders and other third parties. Also in India, the drive to raise capital for 3G auctions and deployment during 2010 led to significant divestiture of mobile towers to independent companies that operate them on an open-access basis. American Tower, another independent tower company, has also been acquiring towers in countries such as Chile, Brazil, Ghana, India, Mexico, Peru, and South Africa, with the aim of providing open access to such infrastructure. Many other regulatory authorities, including those of Bangladesh, Nigeria, and Pakistan, have adopted policies to promote infrastructure sharing, especially in the mobile sector. When promoting voluntary sharing, regulatory authorities and policy makers must balance the potential benefits and costs of such measures, in order to achieve the desired objective of promoting more competitive markets and increased rollout of services. On the wireline side, several governments are promoting a variety of shared infrastructure approaches. In the most interventionist cases, such as Australia, New Zealand, and Singapore, policy makers have directed the establishment of a single, open-access network that will provide infrastructure services on a wholesale basis to a variety of downstream service providers. Rather than establish an entirely separate network, France has taken a more regulatory approach by setting up sharing requirements and obligations for firms building out fiber networks to more rural areas and to apartment buildings. This concept might also be extended to other, often government-owned, entities, such as power companies that maintain towers for electricity distribution. Two main advantages for a vertically integrated firm is the ability to achieve higher economies of scale and lower costs of production by reducing the costs of coordinating upstream and downstream activities. In a competitive market, these efficiencies can benefit consumers through lower retail prices. In such cases, a dominant, vertically integrated operator may strategically discriminate against competitors and stifle competition. Remedies to Anticompetitive Conduct by a Vertically Integrated Operator To address competitive concerns associated with vertical integration, some regulators have required dominant operators to separate vertically to some degree through accounting separation, functional separation, or, in extreme cases, structural separation. Generally, accounting separation requires the vertically integrated operator to maintain separate records for its upstream and downstream costs and revenues in order to allow the regulator to set wholesale prices for the regulated upstream services. These records are typically subject to independent audit and may also be made publicly available. Although the operator must make its costs transparent, under this remedy it is able to continue benefiting from the efficiencies of vertical integration. These guidelines established two levels of accounting separation: detailed segment reporting (applicable to dominant service providers and entities they control) and simplified segment reporting (certain other entities). Currently, incumbent SingTel is the only operator designated as dominant in any market, and it is subject to detailed accounting separation obligations. Functional Separation Obligations under functional separation range from simply requiring the operator to establish separate divisions for upstream and downstream activities to requiring the operator to separate the wholesale and retail divisions physically. This may involve the separation of employees (for example, physical separation of offices and prohibitions on the same employee 122 Broadband Strategies Handbook working for both divisions) and the separation of information (for example, limitations on the type and amount of information that may be shared between divisions). Since there is no actual change in ownership or ultimate control under functional separation,22 the operator can continue to enjoy many of the benefits of vertical integration (European Regulators Group 2007). More intrusive than accounting separation, regulators may implement functional separation in "exceptional" cases where there has been persistent failure to achieve effective nondiscrimination in relevant markets and where there is little or no prospect of effective competition within a reasonable period after less intrusive remedies have been attempted (European Union 2009b, para. Prior to requiring functional separation, the national regulatory authority must first find that all less intrusive, market-based remedies have failed to achieve effective competition.
Diseases
The idea is that if cell wall formation is blocked heart attack in 30s aldactone 25 mg, the organisms will lyse and perish blood pressure chart youth discount aldactone 25mg without prescription, but if metabolism or protein synthesis is blocked - arrhythmia discount aldactone 100mg fast delivery, the organisms merely slow down arrhythmia 25 years old buy 100 mg aldactone with visa. A low dose of a "bactericidal" antibiotic may only inhibit bacterial growth hypertension 8 weeks pregnant cheap aldactone 25mg on-line, while a high dose of a "bacteriostatic" antibiotic will be bactericidal heart attack 30 year old woman discount 25mg aldactone visa. Additionally, organisms which are not proliferating may not be significantly affected by anti-cell wall antibiotics, in which case antiribosomal antibiotics would be more effective. However, if one drowns the cockroach in bug spray (a cockroach-cidal level), the cockroach will perish. Refer to the table below: Page - 175 Tube 1 2 3 4 5 6 Antibiotic Concentration 10. All solid debris (dead or alive organisms) will be centrifuged to the bottom of the tube. After another two days of incubation (on day 4), tubes 1 and 2 are clear, while tubes 3 and 4 are turbid. This means that tubes 3 and 4 contained viable organisms which were inhibited by the antibiotic, but now that the antibiotic is gone, they are able to grow. Tubes A-F are drawn just before the patient receives an antibiotic dose (trough level). For these turbid tubes, we know that active bacterial growth has taken place so these dilutions are neither inhibitory nor bactericidal. The next step is to centrifuge tubes 1, 2, 3, 4, 5 for the peak tubes, and tubes A, B, C, D for the trough tubes. For the peak and trough tubes, after another two days of incubation (on day 4), tubes 1, 2, 3, A, B are clear, while tubes 4, 5, C, D are turbid. Thus tubes 4, 5, C and D contain inhibitory concentrations of antibiotic, while tubes 1, 2, 3, A and B contain bactericidal concentrations of antibiotic. We do know that compared to blood levels, most antibiotics have lower levels in bone and in joint fluid, but higher levels in urine. There is no pus, but overnight, there is a large area of redness noted with slight swelling. There is a 6 by 12 cm oval region of erythroderma with a sharply demarcated border over his mid lateral calf. While the mechanism of action of the different antibiotics are important, this is not as important in most instances. Antibiotic therapy is initiated in three basic ways: 1) empiric therapy, 2) specific therapy, 3) prophylaxis. Empiric therapy is the selection of treatment based on clinical and laboratory information with the exception of culture and sensitivity information. Prophylaxis is the use of antibiotics to prevent an infection which is anticipated. Empiric therapy is based on a three step process: 1) identifying a clinical entity, 2) knowing which organisms cause this entity, 3) selecting an antibiotic which covers these organisms. Some physicians use a two step process which is to identify the clinical entity, then select an antibiotic which is commonly used for this entity. I would prefer that students and physicians in training learn the three step process because it is a deeper level of understanding. This is often true, but it is an oversimplification which has too many exceptions for this rule to be useful. Staph aureus is usually sensitive to penicillinase resistant penicillins and cephalosporins, but resistance to these is becoming more frequent (25% or more). However, it is a certainty that antibiotic resistance patterns will change and new antibiotics will be developed. Such a handbook will provide useful information in learning the three step process. A list of clinical infections and the common organisms which cause these infections. Once a clinical entity is identified, then an antibiotic from this listing can be selected. After utilizing the three step method frequently, you will become very good at this, and most antibiotic decisions in the future will not require the assistance of a handbook, the three step process described below: Step 1. Sometimes laboratory and imaging information may also be necessary to add more certainty to a diagnosis. Staph aureus is usually sensitive to cephalosporins and penicillinase resistant penicillins such as oxacillin and cloxacillin. Staph aureus is about 95% sensitive to clindamycin and this also covers group A strep. For a life threatening infection such as bacterial meningitis, there must be the certainty of 100% coverage. Thus, initial broad spectrum or multiple antibiotics may need to be used empirically. As opposed to a less serious infection such as otitis media or impetigo, in which case 80% coverage certainty may be sufficient. A more experienced physician examines the cellulitis and indicates that this cellulitis is caused by group A strep which more commonly causes large areas of erythroderma surrounding a single skin sore. Staph aureus cellulitis is usually associated with suppuration and a smaller area of redness and induration surrounding a central abscess. When the results of the culture returned identifying the organism and its sensitivity to penicillin, the patient could then be changed to specific therapy with penicillin. Specific therapy utilizes culture and sensitivity information which is usually available 1 to 3 days later. The general principle is to select the antibiotic which is the most effective with the least side effects. Patients with vesicoureteral reflux are at greater risk for urinary tract infections. As a preliminary discussion, antibiotics can be classified into 7 groups: penicillins, cephalosporins, aminoglycosides, sulfonamides, quinolones, macrolides and other. Penicillins can be further classified into three groups: penicillin, broad spectrum penicillins and anti-staph aureus penicillins. With the exception of amoxicillin and ampicillin, the other broad spectrum penicillins cover pseudomonas as well. Broad spectrum penicillins can be combined with penicillinase inhibitors such as clavulanate and sulbactam. It should be noted that amoxicillin is metabolized to ampicillin in the bloodstream. These drugs are targeted against staph aureus which is why this group should more accurately called the antistaph aureus penicillins. Thus, this group should be more appropriately called the anti-staph aureus penicillins, because the only penicillinase producing organism which they cover to a moderate degree is staph aureus. Cephalosporins Cephalosporins are structurally similar to penicillins with a similar mechanism of action. Cephalosporins are difficult to learn because there are many of them and new ones are frequently introduced. In general, all cephalosporins cover all penicillin sensitive organisms with the exception of Listeria and Pasteurella. Coverage for group B streptococci is better with penicillin than with cephalosporins. If a cephalosporin has no clinically useful advantages which separate it from other cephalosporins, then we should purge it from our memory. We will still be exposed to them, because other physicians will prescribe them, and there are additional subtle factors which may slightly favor other cephalosporins. In fact, while Staph aureus may be 25% resistant to the anti-staph aureus penicillins and cephalosporins, Staph aureus resistance to aminoglycosides is 10% or less. Sulfonamides are usually used for gram negative infections such as urinary tract infections; however, they cover many gram positives, such as Staph aureus well. Law suits involving sulfonamides suggest that malpractice occurs when the clinicians fails to warn the patient of adverse reactions such as hemolytic reactions and Stevens-Johnson syndrome. However, in patients with allergies to other antibiotics, sulfonamides may be useful. These drugs have not been used commonly in pediatrics since they are most commonly used in highly resistant adult infections. Erythromycin estolate gets higher tissue levels and is commonly recommended for pertussis. Newer and more expensive erythromycins such as azithromycin and clarithromycin have broader coverage, less side effects and more convenient dosing. Tetracycline use is discouraged in children because it causes staining of teeth, hypoplasia of dental enamel, and abnormal bone growth in children. Vancomycin can also be given orally for pseudomembranous colitis caused by Clostridium difficile. Clindamycin is a useful for the outpatient treatment of cellulitis and other infections commonly caused by group A strep and Staph aureus. Clindamycin is also used for coverage of anaerobes including Bacteroides fragilis. Cephalosporins and vancomycin have largely replaced these older drugs to treat meningitis. Metronidazole (Flagyl) is a anti-parasitic anti-amebic drug, but it also has nearly complete coverage of anaerobes. Thus, when 100% anaerobe coverage is required, the options include metronidazole, clindamycin or chloramphenicol. The broad spectrum penicillins in combination with clavulanate or sulbactam may also cover anaerobes sufficiently. Can the generation of the cephalosporin (in itself) be the sole selection criteria for a particular clinical situation? What empiric antibiotic(s) could be used to cover the organisms in the above question? Similarly, searches for fifth and sixth generation cephalosporin yields some articles. If I was a slick marketer of drugs, I would simply call my new cephalosporin "Tenth Generation" and almost everyone would buy it. The generation is not nearly as important as the specific property of the cephalosporin which makes it clinically useful over another cephalosporin. Bacterial meningitis: Pneumococcus, meningococcus, Haemophilus influenzae type B (HiB). Although trimethoprim/sulfamethoxazole (Bactrim or Septra) is commonly recommended because of its broad coverage for this indication, this drug causes Stevens-Johnson syndrome more commonly than others. If the parents accept this increased risk, then this Page - 181 should be documented on the chart. Most parents are not willing to accept this increased risk since other antibiotics are available. Thus, an acceptable answer here would also be a first generation cephalosporin such as cephalexin. Additionally, since most patients have drug plans, the difference may be negligible. If both medications are efficacious, perhaps it is best to discuss these differences with the patient and give them some input in the decision. He also has a low-grade fever of about 101 degrees axillary for the past two days. His past medical history is significant for ear infections in the past, with his last otitis media being 5 months ago treated with amoxicillin. It is estimated that otitis media comprises 23% of all office visits in the first year of life, and 40% at four to five years when these children start Kindergarten. Therefore, factors hindering the movement of these ossicles, such as pus or fluid in the middle ear, will adversely affect hearing. Otitis media is common in infants and young children with the peak age being between 6 to 18 months of age. Older children may complain of a "plugged" feeling or "popping" in their ears, which is usually bilateral. If severe otalgia is present, then analgesia becomes a major therapeutic consideration. Other less common organisms are Streptococcus pyogenes, Staphylococcus aureus, gram negative enteric bacteria, and anaerobes (5). For this reason, it is recommended that the dose of amoxicillin be increased from 40-50 mg/kg/day to 80-90 mg/kg/day in two to three divided doses. Risk factors include young age (less than 2 years), recent antibiotic use (within the last month), and day care attendance (4). Also recently, azithromycin has been approved for a 30 mg/kg one time dose, or 10 mg/kg dose for three days. Other drugs that are recommended are cefprozil, ceftibuten, loracarbef, and clindamycin (6). At times, tympanocentesis or myringotomy is necessary for resistant cases, at which time a culture can also be obtained. Although a middle ear effusion may be present, an inflamed eardrum or persistent systemic symptoms at this follow-up visit may warrant changing the antibiotic therapy or performing a myringotomy/tympanocentesis. It is estimated that 30-70% of children will have a middle ear effusion 10-14 days later, and that without treatment, 6-26% will have a persistent middle ear effusion after 3 months, with the mean of resolution being about 23 days. Not only do we treat otitis media for symptomatic relief, but also to prevent its complications. Only in a few children does medical therapy fail, and more aggressive measures are needed, such as myringotomy and tympanostomy tubes. As the humidity in the outer ear increases, the stratum corneum in the cartilaginous portion of the ear absorbs water, which results in edema.
The classic triad was found in only 21% of cases and two symptoms were found in 70% of cases in one series of patients with intussusception (1) hypertension pamphlet best 25mg aldactone. Patients with an intussusception may also present with lethargy/altered level of consciousness and pallor blood pressure medication blue pill purchase 100 mg aldactone with amex. The etiology of this lethargic presentation is not known pulse pressure over 80 buy aldactone 100 mg lowest price, but it tends to occur in younger infants narrow pulse pressure uk aldactone 100 mg sale. Some hypothesize that this is due to release of endogenous opioids or endotoxins released from ischemic bowel blood pressure 200 over 100 purchase aldactone 25 mg. The physical examination of a patient with an intussusception may be unremarkable blood pressure levels good generic aldactone 25 mg line. Also, examining the abdomen of an active or Page - 385 crying child can often be difficult. A sausage-like mass in the right upper quadrant and emptiness (the absence of bowel) in the right lower quadrant is clinically indicative of an intussusception. A target sign is viewing the intussusception on cross-section which appears as two concentric circles (created by bowel fat density differences) usually in the right upper quadrant. The crescent sign is formed by the leading edge of the intussusception outlined by gas in the colon forming a crescent (intussusceptum protruding into a gas filled pocket). The absent liver margin sign can be seen if the soft tissue mass of the intussusception is resting at the hepatic flexure of the colon or there is absence of gas in the right upper quadrant making the lower edge of the liver indistinct. Additionally, if the ultrasound does identify an intussusception, a contrast enema must still be performed to reduce the intussusception. A barium enema has been the gold standard in the past for confirming the diagnosis and nonsurgical reduction of an intussusception. Water-soluble contrast has been used and more recently air enema reduction has been introduced. Air leaking into the peritoneal cavity because of intestinal perforation may also be difficult to see. Those in favor of using the air contrast enema technique argue that with perforation, the sudden loss of pressure would signal to the radiologist to stop the procedure. If a tension pneumoperitoneum results, this should be decompressed immediately with an 18-gauge needle. An air contrast enema is advocated as the preferred method by many pediatric radiologists (2), but since there is no clear consensus among radiologists of the best contrast enema option, this decision is best left to the radiologist performing the contrast enema procedure. Several factors are associated with a contrast enema being unsuccessful in reducing the intussusception. These include ileo-ileocolic intussusception, longer duration of symptoms (>12 hours), dehydration, small bowel obstruction, and age greater than 2 years or less than 3 months. The rate of intestinal perforation with nonsurgical reduction of an intussusception is 1% to 3%. A contrast enema is contraindicated in patients who have a bowel perforation, shock, or peritonitis. However, most feel that the patient should be observed in the hospital for 24 hours. Contraindications for non-surgical reduction of an intussusception include all of the following except: a. All three of the "classical triad" of symptoms is found in what percentage of patients with intussusception? A surgeon is consulted and at laparotomy, his entire small bowel is found to be necrotic due to a midgut volvulus. He develops shock requiring aggressive fluid resuscitation, pressors and inotropes. He eventually survives, but he will require parenteral nutrition for the rest of his life, since he does not have enough small bowel to survive with enteral nutrition. In malrotation, the intestines function normally, so the patient is entirely asymptomatic until a complication of the malrotation occurs. Malrotation should really be renamed to "guts on a stalk syndrome" because this is the clinical feature that causes the major complication of malrotation in which the peritoneal attachments suspend the intestines like a stalk rather than a broad fan. This broad attachment (like a rectangular flag) makes it difficult or impossible for the intestinal loops to twist and cause an obstruction. However, in malrotation, the intestines are suspended from a narrow attachment to the back of the abdominal wall, which makes the intestines highly susceptible to twisting about this stalk (guts hanging on a stalk). Once the stalk twists, there is a fair likelihood that it will untwist on its own, relieving the volvulus. How can a malrotation be diagnosed if the patient does not have a midgut volvulus at the time? An ultrasound may be able to identify a misplacement of the superior and inferior mesenteric axes coming off the descending aorta which is indicative of a malrotation, but again, this sign is not 100% diagnostic. This does not necessarily occur with a midgut volvulus which is much more serious. If the patient is able to survive this, parenteral nutrition is required for the remainder of his/her life since there is not enough bowel remaining for enteral nutrition. Sigmoid volvulus involves the large bowel and can often be decompressed by barium enema or other non-surgical procedures. This is opposed to a midgut volvulus, which occurs mostly in children with a malrotation. Approximately half the cases of malrotation will present during the neonatal period with an acute bowel obstruction. What is the most reliable imaging procedure to identify or rule out a malrotation in the absence of a midgut volvulus? Name two different types of intestinal volvulus and describe how they are different. Is it likely that one could have a malrotation and never have a volvulus throughout life? Textbook of Pediatric Emergency Medicine, third edition, 1993, Baltimore, Williams and Wilkins, pp. Textbook of Surgery, the Biological Basis of Modern Surgical Practice, 14th edition. The term "malformation" originates from the embryological formation of the malrotation which is of little or no value for clinicians. About half the patients with a malrotation will present in the neonatal period, with the other half presenting at any other age. Prenatal ultrasonography was done at 32 weeks gestation revealing what appeared to be free intestine floating in the amniotic fluid, coming from the anterior abdominal wall. The mother elected for a cesarean section delivery after fetal lung maturation was assured (at 36 week gestation in this case scenario). The baby looks normal at birth except for matted intestinal loops coming through an anterior abdominal wall defect just to the right of the umbilical cord. Placement of a nasogastric tube to decompress the stomach and warming for maintenance of a normal temperature are done next. No attempt is made to force the exteriorized intestines back into the abdominal cavity. They are usually associated with gut abnormalities, including abnormal rotation and fixation. Embryologically different, a gastroschisis involves the base of the umbilical stalk, with the defect in the abdominal wall always occurring lateral to the base of the umbilicus, through which a portion of the intestine has escaped (usually the right side). This defect may represent an isolated congenital defect in the abdominal wall, or be the result of closure of the celomic cavity while a portion of the intestinal tract remained trapped outside the abdomen, at the base of the umbilical cord. An omphalocele is usually covered by a translucent membrane overlying the bowel and solid viscera. This has allowed the escape of the intestine into the amniotic cavity at different times in fetal development. Some appear edematous and matted that have been exposed to the amniotic fluid for many weeks, while other intestines are glistening and normal looking, as they "escaped" just before birth. Placement of a nasogastric tube to decompress the stomach and maintenance of a normal temperature are essential. Although the definite treatment is surgical, delay in closure has no adverse outcome. Although smaller omphaloceles usually undergo primary closure, giant omphalocele in the neonate is a challenging surgical emergency that requires individualized approaches to operative repair. In general, omphaloceles greater than 6 cm in diameter require silo reduction with silastic interwoven with Marlex. Interesting methods have recently been described utilizing continuous controlled pressure to achieve smooth, rapid, and safe silo reduction of an anterior abdominal wall defect. One example includes a metal tube with larger wheels at each end that is suspended by runners and counterweights, to slowly roll the silo and squeeze the contents into the abdominal cavity. The cesarean section rate was almost identical (19% versus 18%) in both subgroups, the majority of which were performed to protect the abdominal wall defect. Congenital malrotation of the colon usually occurs in patients born with an omphalocele. Although not a serious defect, the anomaly can lead to midgut volvulus and intestinal obstruction in a baby who has previously recovered from treatment of an omphalocele, and therefore must be corrected at the time of initial surgery. Even after successful reduction of the bowel and closure of the defect, normal motor function of the gut may be delayed for weeks to months in cases of gastroschisis. A recent follow-up study was done involving patients post-operatively, from 1-28 years prior. There were fewer neonatal deaths in the last decade, attributed to better operative and perioperative treatment, as well as abortions following improved ultrasound diagnosis (as early as 12 weeks gestation). There was no mention of remaining problems regarding 16 of the 28 omphalocele patients and 10 of the 16 gastroschisis patients. All the remaining problems could be corrected and the longterm results in both conditions were good. An omphalocele arises within the umbilical ring as a central defect, while a gastroschisis involves the base of the umbilical stalk, with the defect in the abdominal wall always occurring lateral to the umbilicus. Although the survival rate of patients with abdominal wall defects has gradually improved, the outcome is largely dependent on coexisting anomalies. Improved ultrasound diagnosis has resulted in some women seeking termination of pregnancy as early as 12 weeks gestation. The influence of delay in closure of the abdominal wall on outcome in gastroschisis. As there were no significant antenatal problems, no prenatal ultrasonography was done. At 5 minutes of age, the baby remains very cyanotic, tachypneic and dyspneic, despite 100% oxygen via mask. The resuscitation team starts bag-mask positive pressure ventilation with 100% oxygen, but the baby becomes bradycardic, therefore he is intubated and ventilated. The heart sounds seemed loudest in the right chest, and the abdomen appears scaphoid. Although in the case above the diagnosis was not made until after delivery, with increasing use of fetal sonography, the diagnosis is commonly made prenatally, often as early as 15 weeks gestation. Unfortunately, more than 40% have associated anomalies of their brain, heart or other regions resulting in a poorer prognosis. Classically, if undiagnosed prenatally, these infants present as a "neonatal emergency" in the delivery room. Rarely, a diaphragmatic hernia presents in an older child, as an incidental finding on physical exam or chest x-ray, or may be "acquired" as a result of traumatic rupture of the diaphragm secondary to a severe blow to the abdomen. Secondly, pass a nasogastric catheter and apply intermittent suction to decompress the stomach (occupying the thorax and acting similar to a tension pneumothorax). The liver partially blocks the pleuroperitoneal canal and limits the amount of bowel that can herniate into the chest. As with any form of ventilation, positive pressure can result in a pneumothorax on the contralateral side, which must be carefully observed for. Pulmonary hypoplasia and immaturity of the lungs remain the leading cause of death, from pulmonary hypertension (right-to-left shunting) with resultant hypoxemia. Conventional ventilatory techniques, with high pressures and hyperventilation used to reverse ductal shunting and cause alkalinization, are now being replaced with ventilatory techniques utilizing the concepts of permissive hypercapnia and high frequency oscillation ventilation. The complications of ventilation including air leaks, barotrauma and consequent bronchopulmonary dysplasia are at least in part circumvented because of these newer techniques. Regardless of the treatment, the goal is to reverse the persistent pulmonary hypertension causing right to left shunting through the ductus arteriosus and foramen ovale. However, no such beneficial effect has as yet been consistently reported in infants with congenital diaphragmatic hernia. As the abdominal contents have been in the thorax for most of fetal development, the abdomen often does not have enough room for the "missing" contents. Forcing the contents into the abdomen will compress the vena cava and compromise respirations by pushing up on the diaphragm. The surgeon may be forced to omit total anatomic closure of the abdominal wall, and utilize skin flaps with only the skin being closed. The pouch created accommodates the intra-abdominal organs, and diaphragmatic action and venous return are unimpeded. Although one may expect a poorer outcome with earlier intrauterine diagnosis, ultrasound, diagnosis before 25 weeks of gestation was not found to be a uniformly bad prognostic indicator (median mortality, 60%). Endotracheal intubation with gentle ventilation, followed by nasogastric suctioning is immediately indicated. His mother states that the vomiting has gotten progressively worse and now seems to "shoot out of his mouth. The vomiting occurs immediately after feeding and varies in intensity, depending upon the degree of stenosis present.
The work ecliptic arrhythmia research summit cheap 25mg aldactone free shipping, and showed the causes of her was almost entirely fi11ished pulse pressure 65 discount aldactone 25mg, when he libration blood pressure medication valturna purchase aldactone 100 mg fast delivery. The laws of this motion prehypertension lower blood pressure 25 mg aldactone for sale, which died (1784) prehypertension 21 years old order aldactone 100mg online, leaving many writings relat he determined with much accuracy blood pressure chart during the day order aldactone 25 mg on line, are i11g to his great topographical under one of his finest discoveries. In Roussillon, and, when measured 100 years 1789, he presented to the national assem later, showed a difference of only 21 bly the Carte Topographique de France, toises. His nephew, Cassini de bnt lost the copperplates of the Carle de Thury, has published his biography, writ Prance, which had cost half a million ten by Cassini himself, under the title francs. It is probable that the ancient merchants kept their true situation secret from interested views, which, in those times, could easily be done. In the famous civil war that broke out between Pompey and Cresar, he espoused the cause of the former, and, as commander of his naval forces, ren dered him important services. When Ciesar, after the victory at Pharsalia, was in pursuit of Pompey, Im advanced with a few vessels, while crossing the Helles pont, against a fleet of 70 sail command ed by Cassius, and called upon him to surrender. But, when it became evident that Ciesar was aiming at sole sovereignty, Cassius, who was a zealous republican, resolved to destroy the usurper, and exe eutetl his plan, with the aid of seyeral fellow-conspirators, ll. They were met by Octavius and Antony, who professed themselves the avengersofCre sar, at Philippi. The wing which Cas sius commanded being defeated, he ima gined that all was lost, and killed himself, B. In the form of the bill and their mode of living, they more closely resemble the gallinaceous birds. For Theodoric he also wrote his compilation ofletters, Variarum Epw tolarum Li,bri Xll. He likewise composed Historia Gotlwrum (a History of the Goths), of which we have an epitome by Jornandes, and several theological works of little impo1tance. She dared to compare her beauty to that of the Nereides, who, en raged thereat, besought Neptune for ven geance. Thus it appears that in ancient times, as well as in modern, nations have had to suffer for the faults of their mas ters. In 15i2, a new and brilliant star appeared in it, which, however, after a slwrt time, gradu ally diminished, and at last disappeared entirely. It was thought, at that time, by many persons, that this was the star which appeared to the wise men in the East. The Cassiquiari flows from the Orinoco, and joins the Rio Ne gro, which last is a large tributary of the Amazon. The reality of this communi cation, which had been previously assert ed by the Jesuit missionaries, was con firmed by the celebrated traveller Humboldt. There are some naked, rigid quills on the wings, which are used as,veapons of defence. From the form of its head, and bright eyes, the cas sowary is of a fierce and threatening aspect. This, however, is not a true in dication of its character, which is rather timorous and shy. The head and neck together measure 18 mches, and the largest toe, including the claw, is 5 inches long. All the feathers of the cassowary are of the same kind, being entirely designed for covering, and exter nally are all of one color. They general ly grow double, having two long shafts growing out of a short one attached to the skin. The double feathers are all of un equal length, some on the rump being 12 or 14 inches Jong, while others are only 3. The stern or shaft is flat, shining, black, and knotted below, having a beard arising from each knot. The beards at the ends of the large feathers are perfectly black, and towards the root of a tawny gray. The feathers on the head and neck are so short and scattered, that the skin appears naked, except towards the hind part of the head, where they are somewhat longer. It also kicks violently when, in a state of captivi ty, it is provoked to anger, and can inflict a very severe blow. The eggs of the ga leated cassowary are of a grayish-ash color, verging to green, and are neither as round nor as large as those of the ostrich. The shell is not very thick, and is marked by numerous little deep-green tubercles. The head is destitute ofthe helmet, and feath ered throughout, except around the ear. It has neither caruncles to tl1e neck nor prickles on the wings, the nails of the toes are nearly equal. The legs are stout, similar to those of the galeated species, but jagged or dentated along the whole of their back part. At first, he painted only in dis- other officers, for enmity to the prince temper and fresco, and was in high repu- of peace. The splendor of 9000 regular troops, and about 30,000 this new mode of coloring was very militia, he defeated general Dupont (See much admired, and, by a pretended Baylen. This he effected now the companion in anus of the duke without any suspicion, and continued to of,vellington, and displayed great mill practise his ill-acquired art with great tary talent in the battle of Vittoria, which success. The real author of this atro- was, in part, won by his bravery and the cious act was never discovered until An- valor of his troops. The regency depriv drea made a full confession of his guilt, ed him of his command, and appointed shortly before his death, which happened him counsellor of state. The best of his remaining works minister of war, "I have the satisfaction are at Florence, in the church of St. But the llivis ion into castes was nowhere so perfectly formed, and so entirely interwoven in the whole fabric of civil society, as in Egypt and India. The class of priests, who formed, in some respects, a highly-privileged order of nobility, and maintained possession of the offices of state, was the highest. Next followed the soldiers, who were divided into two classes, and whose occupation was hered itary. Of the remaining castes, tlie hus bandmen, the watermen (who navigated the Nile), the interpreters (who arose sub sequently to the rest, and sprung from the Greeks who were invited into the coun try), and the two castes of herdsmen, formed a gradation of ranks, the order of which is not known, any further than that the herdsmen were the lowest. Among tl1ese the swineherd was consid ered impure, and despised, and was ex cluded from the temples. After the battle of Aboukir, Castelcicala persuaded his cqurt to declare war against France. Two years after, he was Sicilian ambassador in London, and still later at the French comt. In 1816, he signed the important treaty admitting all British pro ductions and manufactures into Sicily on paying 10 per cent. After the rev olution (1820), he was appointed ambas sador to:Madrid, but remained in Paris. He died in 1794, being at that time an honor ary member of the royal society, and of the academy at Paris. His letters (Padua, 17ti9) are valuable contributions to political and lit erary history. Notwithstanding his advanced age, the vigor and activity of his mind were still unimpaired. His vivacity, his naivete, seasoned Ly a delicate irony, and his knowledge of the world, made his conversation very attractive. At the same time, he was remarkable for the firmness of his character and the regularity of his habits. His Novelle galanti were republished at Paris, 1804, under the title Novelle di Giamb. Almost all are of a licentious character, but writ ten in a lively, original and graceful style. In 1513, Castiglione appeared as ambas sador at the court of Leo X,:where he became intimate with the most distin guished literati and artists. The climate is temperate, the soil naturally fertile, but the cultirntion back ward, and the country thinly inhabited. Antonio Amar, in September of that year, in consequence of the revolutionary movement at Quito, and on other occasions previous to the deposition of Amar, he distinguished him self by his zeal in the cause of America. Ile was also a member of the constitu,ent college, as it was called, which assembled at Bogota in 1811, and organized the state of Cundinamarca. In the congress at Neyba, in October, 1812, he was one of the two delegates from Tunja, of which province, in the following year, we find him the acting govemor. After the change in the form of government in 1814, when the author ity of the executive was increased, the three persons elected to exercise the exec utive power being absent, Castillo was one of the deputies appointed to the tempora ry discharge of their duties. He was a member of the conven tion of Ocana for the province of Cartha gena, and was elected president of that body. He was one of the twenty deputies who withdrew from the assembly, and testified their confidence in Bolivar in a printed exposition oftheir motives. It is situated on a promontory, ou the east side of Penobscot bay, a little below the entrance of Penobscot river into the bay. It has an excellent and very spacious harbor, capable of receiving ships of the largest size, and accessible at all seasons of the year. The kind of sand most employed is loam, which possesses a sufficient por tion of argillaceous matter to render it moderately cohesive when damp. The mould is formed by burying in the sand a wooden pattern, having exactly the shape of the article to be cast. But, wheu the shape is such that the pattern could not be extracted without breaking the mould, two flasks are necessary, having half the mould formed in each. The first flask is filled with sand, by ramming it close, and is smoothed off at the top. After one or more holes are made in the top, to pennit the metal to be poured in, and the steam and air to es cape, the flasks are separated, and the pat. These are taken off from the statue, and, when afterwards replaced or put together without the statue, they constitute a perfect mould. The advantage of the elastic mould is, that it separates more easily from irregular surfaces, or those with uneven projections and under cut tings, from which a common mould could not be removed without vio" Plaster casts are varnished by a mixture o(soap and white wax in boiling water. When intended to resemble bronze, a soap is used, made oflinseed oil and soda, colored the sulph. In some other irregular articles, as andirons, one part is cast first, and afterwards inserted in the flask which is to form the other part. The metal for small articles is usu ally clipped up with iron ladles, coated with clay, and poured into the moulds. In large articles, such as cannon, the mould is formed in a pit dug in the earth near the furnace, and the melted metal is. Cannon-balls are sometimes cast in moulds made of iron, and, to prevent the melted metal from adhering, the inside of the mould is covered with powder of black lead. These rollers are afterwards turned smooth in a powerful lathe, which has a slow mo tion, tliat the cutting tool may not become heated by the friction. Copies are most frequently taken, botl1 from new models, and from old statues, by casting them in plaster. Plaster is prepared for use by pulverizing common gypsum, and exposing it to the heat of a fire until its moisture is wholly expelled. The liardness afterwards in creases by keeping, till it approaches the character of stone. A quantity of liquid plaster sufficient for the mould is then poured on, immediately after being mixed, and suffered to harden. Statues intended to occupy situations in which they may be exposed to violence are commonly made of bronze. This material resists both mechanical injuries and decay from the influence of the at mosphere. The moulds in which bronze statues are cast are made on the pattern, out of plaster and brick-dust, the latter material being added to resist the heat of the melted metal. The mould, with its core, is then thoroughly dried, and the core secured in its central position by short bars of bronze, which pass into it through the external part of the mould. The whole is then bound with iron hoops, and, when placed in a proper situation for casting, the melted bronze is poured in through an aperture left for the purpose: of course, the bronze fills the same cavity which was previously occupied by the clay, and forms a metallic covering to the core. The two broth ers were inseparable companions, equally brave and spirited, and attached to each other with the fumiest affection. Castor -was particularly skilled in the art of break ing horses, and Pollux in boxing and wrestling. After their return, they re leased their sister Helen from the con finement in which Theseus had for some time held her. They wooed the daughters of Leucippus, Phre be and Ilaria, and were each obliged to contend for their mistresses with their ri imls, Idas and Lynceus, the sons of Apha rcus. Jupiter listened to his request, and Pol lux and his brother alternately descended to Orcus, and returned to life. It is doubtful whether the ancients understood tliem as being togetl1Cr or separate in their alternate passage between the upper and tl1e lower worlds. Those of the third class, to dis tinguish them from the two others are frequently termed entire eunuchs. The castration of adults produces some change in tl1e dis position, but little in the bodily. Accord ing to the accounts of ancient historians, the Greeks, particularly the Lydians, cas trated women. The latter are said to have used these beings as guards of their wives arid daughters. Nothing but an immediate and fatal injnry to the parts authorizes an operation of such vital consequence to the lmman race. Among the evils which religious enthusiasm has at all times pro duced, castration is conspicuous.
Order aldactone 100 mg with mastercard. LearningTools: Blood Pressure Basics - Audio-Visual Coordination Skills.