Anatomical sites

TCA is a chemical cauterant the application of which to the skin causes protein denaturation, so called keratocoagulation, resulting in a readily observed white frost. The degree of tissue penetration and ensuing injury by a TCA solution is dependent on several factors, including strength of TCA used, skin preparation and anatomic site. 

Evasion of tolerance to self antigens. Hidden or sequestered antigens do exist, for instance spermatozoa and eye-lens tissue. These are confined to anatomical sites which do not have access to lymphoid tissue, and exposure of the above to lymphoid cells as a result of surgery or accident results in the production of the corresponding antibodies. 

Many areas of the human body are colonized with bacteria— this is known as normal flora. Infections often arise from one s own normal flora (also called an endogenous infection). Endogenous infection may occur when there are alterations in the normal flora (e.g., recent antimicrobial use may allow for overgrowth of other normal flora) or disruption of host defenses (e.g., a break or entry in the skin). Knowing what organisms reside where can help to guide empirical antimicrobial therapy (Fig. 66-1). In addition, it is beneficial to know what anatomic sites are normally sterile. These include the cerebrospinal fluid, blood, and urine. 

Findings on physical examination, along with the clinical presentation, can help to provide the anatomic location of the infection. Once the anatomic site is identified, the most probable pathogens associated with disease can be determined based on likely endogenous or exogenous flora. 

Haemophilus ducreyi, a gram-negative bacterium, has been isolated as the causative organism of chancroid, a genital ulcerative disease usually accompanied by inguinal lymphadenitis and bubo formation. Chancroid may possibly spread to other anatomic sites, a clinical feature first discovered by Ducrey in 1889.37... 

An alternative classification, the Cierny-Mader staging system, is based on anatomic site and physiologic status of the patient.1 This classification scheme was developed for chronic osteomyelitis involving long bones and has limited application for small bones and digits. The detailed stratification has the greatest utility in clinical trials since it would permit comparison of treatment regimens in patients with diverse comorbidities and infection sites. 

SSIs are defined and reported according to Centers for Disease Control and Prevention (CDC) criteria.5 SSIs are classified as either incisional or organ/space. Incisional SSIs are further divided into superficial incisional SSI (skin or subcutaneous tissue) and deep incisional SSI (deeper soft tissues of the incision). Organ/space SSIs involve any anatomic site other than the incised areas. For example, a patient who develops meningitis after removal of a brain tumor could be classified as having an organ/space SSI. An infection is considered an SSI if any of the above criteria is met and the infection occurs within 30 days of the operation. If a prosthetic is implanted, the timeline extends out to 1 year. 

Dieu MC, Vanbervliet B, Vicari A, et al. Selective recruitment of immature and mature dendritic cells by distinct chemokines expressed in different anatomic sites. J Exp Med 1998 188(2) 373-386. 

Thus, if the hepatic clearance for a drug is largely relative to the hepatic blood flow, the extent of availability for this drug will be low when it is given by a route that yields first-pass effects. The decrease in availability is a function of only the anatomical site... 

Erkkila J, Armstrong R, Riihimaki V, et al. 1992. In vivo measurements of lead in bone at four anatomical sites long term occupational and consequent endogenous exposure. Br J Ind Med 49 631-644. 

For each anatomic site listed, select the catecholamine neurotransmitter found in the highest amounts. 

The figure below shows proposed sites of action of drugs. For each of the diuretic agents below, choose the anatomic site in the schematic diagram of the renal nephron where the principal action of the agent occurs. 

FIGURE 53-1 Illustrative drawing of the temporal lobe system in the human brain. (A) Anatomical sites, marked by black dots, within the temporal lobe where electrical stimulation evoked experiential responses in Penfield s patients. (B) The location of the hippocampus and amygdala inside the temporal lobe. 

Ulcerative colitis and Crohn s disease differ in two general respects anatomic sites and depth of involvement within the bowel wall. There is, however, overlap between the two conditions, with a small fraction of patients showing features of both diseases (Table 26-2). 

Infected individuals may be symptomatic or asymptomatic, have complicated or uncomplicated infections, and have infections involving several anatomic sites. 

Approximately 30 y after exposure, there were no significant increases in mortality from overall cancer or cancers at specific anatomical sites, in diseases of the respiratory system, or in overall mortality noted in this cohort. However, the exposure period covered by the study was short, the exposed groups were small, and the exposure levels were not well documented. Consequently, evidence presented in this study is inadequate to assess the carcinogenicity of phosgene. 

Back in 1913, adrenaline was found to cause either constriction or relaxation of blood vessels, depending on the anatomical site. Scientists correctly concluded that there must be two classes of adrenergic receptors. These are termed alpha and beta adrenergic receptors. When adrenaline hits the alpha-type receptor, blood vessel constriction results at the beta-type receptor, blood vessel relaxation results. Thus, adrenaline and noradrenaline are nonspecific agonists (activators) at adrenergic receptors. 

Oifactory epitheiium the anatomical site for olfactory receptors. 

Spatial cooperation is a term coined to describe a situation when disease in one particular anatomic site is missed by one modality but is treated adequately by another. The essence of this is that radiation is a local therapy that will not impact on metastatic disease beyond the planned field borders. Systemic cytotoxic chemotherapy is traditionally used to address the potential distant spread of cancer. In the original description of this mechanism there is no assumption of an interaction between the drugs and radiation with the idea being that the best radiation and best chemotherapy be administered independently of toxicities. The classic example used in several textbooks to illustrate this is the treatment of childhood leukemia with systemic chemotherapy, while their central nervous system, a potential sanctuary site where disease is not treated adequately by chemotherapy, is treated by radiation (28). The reality of the interaction between radiation and chemotherapy is that the dose and timing of radiation are adjusted accordingly to minimize their impact on the neural tissues. 

A 2-year randomized, double-blind, placebo-controlled trial in 301 healthy postmenopausal women demonstrated that by increasing the Ca intake of women previously habituated to inadequate intakes (i.e., extremely low = <400 mg Ca/day or low = >400 to <650 mg Ca/ day), the bone loss that characteristically occurs during postmenopause can be attenuated or even halted (Dawson-Hughes et al., 1990). The protective effects of Ca were dependent on the anatomical site, years since menopause, and the source of supplemental Ca used. Early postmenopausal women (<5 years) generally experience a more accelerated rate of bone loss compared to women >6-year postmenopausal, in whom the rapid rate of bone loss finally slows. The subjects were randomized to... 

Pathophysiologically, thrombosis is the same sequence of events but now occurring in abnormal anatomical sites with intravascular obstruction that results in distal tissue ischaemia. These are often systemic disorders affecting the whole circulation and are described as hypercoagulable syndromes. Defects may lie at the level of the endothelium, inappropriate activation of the coagulation cascade or impaired activity of the fibrinolytic system. Segments of thrombus can become detached and travel peripherally in arterial tree, giving rise to acute insufficiency. Conversely, on the venous side, these are... 

Variation in penetration at different anatomic sites Drug penetration is inversely related to thickness of the stratum corneum. Thus, permeability (and often toxicity) is greater in areas of thinner skin, such as the face or scrotum. 

Although a carcinogen may act upon more than one target, the specificity of an association (an increased occurrence of cancer at one anatomical site or of one morphological type) adds plausibility to a causal relationship, particularly when excess cancer occurrence is limited to one morphological type within the same organ. 

The ascending NE pathway in the CNS begins with projections from the locus ceruleus, an anatomical site encompassing neurons (containing 85% to 90% of central NE stores) that project to the... 

Physiologically, in both normal and hypertensive individuals, blood pressure is maintained by moment-to-moment regulation of cardiac output and peripheral vascular resistance, exerted at three anatomic sites (Figure 11-1) arterioles, postcapillary venules (capacitance vessels), and heart. A fourth anatomic control site, the kidney, contributes to maintenance of blood pressure by regulating the volume of intravascular fluid. Baroreflexes, mediated by autonomic nerves, act in combination with humoral mechanisms, including the renin-angiotensin-aldosterone system, to coordinate function at these four control sites and to maintain normal blood pressure. Finally, local release of vasoactive substances from vascular endothelium may also be involved in the regulation of vascular resistance. For example, endothelin-1 (see Chapter 17) constricts and nitric oxide (see Chapter 19) dilates blood vessels. 

Examination of stained specimens by microscopy or simple examination of an uncentrifuged sample of urine for white blood cells and bacteria may provide important etiologic clues in a very short time. Cultures of selected anatomic sites (blood, sputum, urine, cerebrospinal fluid, and stool) and nonculture methods (antigen testing, polymerase chain reaction, and serology) may also confirm specific etiologic agents. 

Rabies Rabies immune globulin 20 IU/kg. The full dose should be infiltrated around the wound and any remaining volume should be given IM at an anatomic site distant from vaccine administration. Postexposure rabies prophylaxis in persons not previously immunized with rabies vaccine. Must be combined with rabies vaccine. 

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