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By J. Tyler. Chicago-Kent College of Law.

In the extrinsic pathway purchase 20 mg levitra professional with visa erectile dysfunction treatment garlic, factor X is ac- Factor V Proaccelerin Labile factor tivated by a complex consisting of activated factor VII discount 20 mg levitra professional fast delivery causes of erectile dysfunction in young adults, Factor VII Proconvertin Serum prothrombin 2 conversion accelerator Ca , and factor III (tissue factor). Activation of this com- (SPCA) plex by tissue factor bypasses the requirement for coagula- Factor VIII Antihemophilic factor Platelet cofactor 1 tion factors VIII, IX, XI, and XII used in the intrinsic path- Factor IX Christmas factor Platelet thromboplastin way. In the intrinsic pathway, clotting is initiated by the component activation of factor XII by contact to exposed surfaces, such Factor X Stuart factor as collagen in the subendothelial matrix. The activation of Factor XI Plasma thromboplastin factor XII requires several cofactors, including kallikrein antecedent and high-molecular-weight kininogen. In this pathway, Factor XII Hageman factor Contact factor factor X is activated by a complex consisting of factor VIII, Factor XIII Fibrin stabilizing factor 2 factor IXa, platelet factor 3, and Ca. While the blood clot resolves, multiple factors partici- There are many points of interaction between the two pate in wound healing. Optimal wound healing requires the pathways, and no one pathway will account for hemosta- recruitment or generation of new tissue cells as well as new sis. For example, thrombin generated during activation of blood vessels to nourish the repairing tissue. Thus, secreted the extrinsic pathway is an essential cofactor for factor VIII proteins and lipids that attract cells (chemoattractants), in- of the intrinsic pathway. Factor VIIa of the extrinsic path- duce cells to proliferate (mitogens), and induce primitive way directly activates factor IX of the intrinsic system. The many additional points of interaction are tissue and repair the injured area. The healing area is vas- beyond the scope of this discussion, but the concept of in- cularized by a process known as angiogenesis, the forma- dependently acting intrinsic versus extrinsic coagulation tion of new blood vessels from preexisting ones. However, the activity of activated during clotting, play an important role in the an- the intrinsic system and the extrinsic system are monitored giogenic response because they secrete factors that induce individually in clinical coagulation tests for diagnostic pur- proliferation, migration, and differentiation of two of the poses. The test used to monitor activity of the intrinsic sys- major components of blood vessels, endothelial cells, and tem is the partial thromboplastin time (PTT). While plasma can eventually clot in the absence of conjunction with protein growth factors, this lipid induces surface contact, localization and assembly of coagulation the proliferation of new tissue cells to replace damaged factors on cell surfaces amplifies reaction rates by several ones and drives the formation of new blood vessels until the orders of magnitude. It does so by inducing the mi- Clot retraction is a phenomenon that usually occurs gration, proliferation, and differentiation of fibroblasts, within minutes or hours after clot formation. The clot draws smooth muscle cells, and endothelial cells at the site of tis- together, extruding a very large fraction of the serum. Sphingosine 1-phosphate exerts its effects opti- retraction requires platelets. Clot retraction decreases the mally when acting in conjunction with protein growth fac- breakdown of the clot and enhances wound healing. Recent research has been undertaken to de- mechanisms exist to regulate and eventually reverse the fi- fine, in detail, the biochemical events that drive the angio- nal consequence of coagulation in order to allow healing to genic response because directed regulation of angiogenesis proceed. Platelet function is strongly inhibited, for exam- has profound clinical implications. For example, exoge- ple, by the endothelial cell metabolite prostacyclin (PGI2), nously applied angiogenic factors may prove useful in ac- which is generated from arachidonic acid during cellular celerating repair of tissue damaged by thrombi in the pul- activation. Activated endothelial cells also release tissue monary, cerebral, or cardiac circulation. In addition, plasminogen activator (TPA), which converts plasmino- angiogenic factors may assist in the repair of lesions that gen to plasmin, a protein that hydrolyzes fibrin, resulting normally repair slowly—or not at all—such as skin ulcers in in dissolution of the fibrin clot in a process called fibrinol- patients who are bedridden or diabetic. Thrombin bound to thrombomodulin on the surface Inhibition of angiogenesis may have profound clinical of endothelial cells converts protein C to an active pro- implications also, since unwanted tissues, such as growing tease. Activated protein C and its cofactor, protein S, re- tumors, require the development of blood vessels to sur- strain further coagulation by proteolysis of factors Va and vive. Furthermore, activated protein C augments fibrinol- response, either by acting on the factors involved or the ysis by blocking an inhibitor of TPA. Finally, antithrombin cells that respond to them, may prove particularly useful in III is a potent inhibitor of proteases involved in the coagu- the treatment of patients with cancer. The activity of an- maceuticals are currently being evaluated for their use as tithrombin III is accelerated by small amounts of heparin, a regulators of angiogenesis, including thrombospondin, an- mucopolysaccharide present in the cells of many tissues. Further research will determine if these agents are ef- in which intravascular clot formation leads to severe prob- fective in patients and will identify new, specific regulators lems, including embolism and stroke. CHAPTER 11 Blood Components, Immunity, and Hemostasis 209 REVIEW QUESTIONS DIRECTIONS: Each of the numbered (E) Adult thymus (D) Release of tissue thromboplastin items or incomplete statements in this 5. What is the process that amplifies the (E) Conversion of fibrinogen to section is followed by answers or by number of T cells or B cells fibrin completion of the statement.

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First cheap 20mg levitra professional mastercard erectile dysfunction protocol amino acids, 70 to 80% of all malpractice claims today are found to be without merit (i 20 mg levitra professional mastercard impotence natural. So it cannot be reasonably argued that the existence of claims against a doctor is evidence of poor medical practice. Expressed differently, the majority of malpractice claims in the United States today are filed against good doctors. Further evidence that rising malpractice premiums are not caused by bad doctors can be found in a review of additional data. It is a reasonable rule of thumb in any given year that about 2% of physician- policyholders will account for approx 50% of the claims losses (16). This leads some to argue that eliminating these offenders would dra- matically reduce premium rates. For this to be true, the same 2% of doctors would have to account for half the losses in succeeding years, and this is not the case. Although the rule of thumb is reliable enough, the doctors involved are different each year. Were this not true, other physicians would not practice with them, and insurance companies would certainly not insure them. This ratio is driven by the reverse causation: 2% of the plaintiffs receive 50% of all indemnity, and the 2% of doctors involved are not predictable, or in most cases even culpable (see below). This is not unexpected in a system so subject to the effects of outlier verdicts. A review of the files of a national medical malpractice insurer indi- cates that less than 1% of its physician-policyholders have two paid claims over a 10-year period of time (16). The likelihood that a physi- cian who has one paid claim will have a second in the succeeding decade is only one in five (16). Therefore, even paid claims do not reliably identify a group of physicians practicing substandard medicine. Finally, the Harvard Medical Practice Study (25) looked at the actual litigation that arose from the more than 32,000 medical records they reviewed and concluded that there was no relationship whatever between the presence or absence of medical negligence and the out- come of malpractice litigation (26). The only variable correlated with the outcome of litigation was the degree of injury. Plaintiffs with the most serious injury were more likely to be successful in court, irre- spective of whether the injury was caused by negligence. Chapter 15 / The Case for Legal Reform 211 Because the majority of malpractice claims are found to be without merit and the extent of injury is more strongly correlated with litigation outcome than with medical negligence, insurance companies cannot predict with any certainty the likelihood that an individual physician will incur malpractice liability in the future. This means premium rates must be predicated primarily on group, rather than individual, experience. In this context, medical specialty and geography (location of the practice) are more important determinants of rates than a physician’s personal experience. Using the extremes as an example, it is easy to see the limits of experience rating in the context of medical malpractice insurance. A physician with no claims could argue that his or her premium should be close to zero. On the other hand, following a single million-dollar claim, the physician’s rate the following year could be many hundreds of thou- sands of dollars. Given the facts above, this would be illogical as well as unfair and would undermine the very notion of insurance. Therefore, in most cases the premium burden is evenly divided among physician groups with only modest experience-based discounts or surcharges actuarially creditable. The Settlement Issue Personal injury attorneys sometimes argue that outlier jury verdicts could be avoided if insurance companies settled claims more readily (27). First, physician defen- dants win approx 80% of malpractice trials (5), making it difficult to argue that those claims should have been settled. Second, the physician, not the insurance company, is the defendant and usually retains the right to make any decision on settlement.

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This page intentionally left blank Chapter 19 The Nurse’s Role in MS Research Objectives: Upon completion of this chapter safe levitra professional 20 mg erectile dysfunction instrumental, the learner will: Describe the roles and responsibilities of the nurse in MS research Identify key concepts in the research processResponsibilities of the research coordinator A buy levitra professional 20 mg otc erectile dysfunction ginseng. Investigator’s brochure—a detailed, confidential description of the structure and formulation of the drug, and a summary of the studies and adverse events. Source documents—documents that contain all the clinical information gathered during a visit. Case report forms—concise information reflective of the source documents entered into duplicate forms that are collected and returned to the sponsor for data entry. Open label—the investigators and patients are aware of what drug or treatment is being tested. Single-blinded study—the patient is blinded to the treatment but the investigator is aware of what is being tested. Double-blinded study—neither the investigator nor the patient knows who has been randomly assigned to what treatment (active therapy or placebo). Cross-over study—participants receive either placebo or tested therapy over a specific time, then investigational drug for the remainder of the study. Informed consent is obtained from the subjects or from a legal representative. The research plan makes adequate provision for monitoring the data to ensure the safety of subjects. The consent must be easily understood by a lay person and must contain the following: A. An explanation of the purpose of the research, the design or the study, and procedures that are experimental C. A description of any foreseeable risks or discomforts including, for women who are able to have children, risks to childbearing or to the fetus. A disclosure of appropriate alternative procedures or course of treatment, if any, that may be advantageous to the subject F. A statement describing the extent to which confidentiality of records will be maintained, including the fact that the FDA might inspect the records G. For research involving more than a minimal risk, an explanation as to whether compensation and medical treatments are available H. An explanation of who should be contacted for answers to pertinent questions about the research and the research subject’s rights I. A statement that participation is voluntary, refusal to partici- pate will not result in any penalty or loss of service to which the subject is otherwise entitled, and that the subject may withdraw at any time without penaltyAdverse events A. Adverse drug experience—any unfavorable and unintended sign, symptom, or disease temporally associated with the use of investigational product B. Serious adverse drug experience—any experience that results in death, a life-threatening adverse event, inpatient hospitalization 98 NURSING PRACTICE IN MULTIPLE SCLEROSIS: A CORE CURRICULUM or prolongation of hospitalization, a persistent or significant disability or incapacity related to the research C. Unexpected adverse drug experience—any adverse experience, the specificity or severity of which is not consistent with the current investigator’s brochureNursing assessment A. How realistic are the patient’s expectations of what the drug under study will and will not do for MS? Does the person understand that there might be a chance of receiving a placebo (in placebo-controlled studies)? Is the patient committed to the frequency of visits, testing requirements, and procedures outlined in the consent form and protocol? How successful has the patient been in the past in terms of keeping appointments and adhering to treatments? Does the patient lack adequate insurance for currently available treatments? Is the patient experiencing a decline in functional status despite aggressive therapeutic interventions? Keep in touch with other nurse coordinators for support and information.

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In low- interest rate environments cheap levitra professional 20 mg overnight delivery impotence from prostate removal, premiums must more closely match costs discount levitra professional 20mg with amex erectile dysfunction protocol ebook. In higher return settings, insurers may be able to sell insurance for less than cost and still remain solvent. CLAIMS MADE VS OCCURRENCE COVERAGE Before the insurance crises of the 1970s, malpractice insurance was sold on an occurrence basis. Any claim arising from an event occurring in the policy period would be covered, regardless of when the claim was reported or when in the future it needed to be paid. This type of policy makes it difficult for insurance companies to predict the ultimate cost of losses, because today’s premiums must cover future losses regardless of when they are reported. The mass litigation surrounding asbestos and toxic waste that is occurring presently, many decades after the insurance was priced and sold and sometimes even prior to the identification of the potential risk, illustrates the difficulty with sustain- ing the occurrence form of insurance. For this reason, since the late 1970s, the majority of medical malpractice insurance policies for physicians is sold on a claims made basis. This form requires that a covered event must occur and the claim must be made (reported) during the policy period. Claims made coverage can be extended back by adding nose coverage, in which the insurer agrees to cover claims made during the policy period based on events that occurred prior to the inception date of the policy. When a physician retires or chooses to move to a different insurance carrier, he or she may obtain tail cover- age. This provides insurance for a covered event occurring during the policy period, even if the claim is not reported until later. In the case of a physician moving from one carrier to another, the individual can choose between tail coverage with the expiring carrier and nose cover- age with the new carrier to accomplish the same purpose. INCURRED LOSS AND RESERVES Incurred loss represents the sum of losses actually paid plus a reserve for the costs of anticipated future losses. Loss reserves are both an Chapter 1 / Insuring the Practice of Medicine 7 estimate of the eventual cost of claims that are reported but still open and claims that have occurred and will be covered but have not yet been reported to the insurance company. The latter type of loss reserve is needed only for occurrence insurance and tail coverages. As the claim for which a reserve is established closes, the final reserve, by definition, will match the actual cost of the claim. In addi- tion, as more claims close and additional information on actual cost trends becomes known, the estimate of the ultimate cost of those claims that are still open may change. If the ultimate cost of losses exceeds the original reserve estimate, the company would be said to be underreserved. If reserves exceed the actual cost of losses, the com- pany would be said to be overreserved. In either case, the actual reserve figures must be adjusted as soon as available information warrants. PROFIT OR LOSS For most insurers, income is the sum of premium and investment income minus the cost of claims, underwriting, and other operating expenses. The combined ratio is defined as losses plus expenses divided by premium. It is a measure of the percentage of each premium dollar going to losses and expenses. A combined ratio of 100% means the company’s claims losses and expenses exactly equal the premium col- lected. Insurance companies writing at a combined ratio of 100% would then have profit equal to investment income. Since the start of the recent crises beginning in 2000, the combined ratio of the average malpractice insurer has been between 130 and 140%, meaning that for every pre- mium dollar collected, $1. Obviously, such numbers produce very large operating losses even when invest- ment income is included. SURPLUS An insurance company’s assets minus its liabilities equal its surplus.