Urine risk measurement

INEFFECTIVE TISSUE PERFUSION RENAL The patient taking an aminoglycoside is at risk for nephrotoxicity. The nurse measures and records the intake and output and notifies the primary health care provider if the output is less than 750 ml/day. It is important to keep a record of the fluid intake and output as well as a daily weight to assess hydration and renal function. The nurse encourages fluid intake to 2000 ml/day (if the patient s condition permits). Any changes in the intake and output ratio or in the appearance of the urine may indicate nephrotoxicity. The nurse reports these types of changes to the primary health care provider promptly. The primary health care provider may order daily laboratory tests (ie, serum creatinine and blood urea nitrogen [BUN]) to monitor renal function. The nurse reports any elevation in the creatinine or BUN level to tiie primary health care provider because an elevation may indicate renal dysfunction. 

C.P. Weisskopf and J.N. Seiber, New approaches to the analysis of organophosphate metabolites in the urine of field workers, in ACS Symposium Series Biological Monitoring for Pesticide Exposure Measurement, Estimation, and Risk Reduction, eds. R.G.M. Wang, C.A. Franklin, R.C. Honeycutt, and J.C. Reinert, American Chemical Society, Washington, DC, pp. 206-214 (1989). 

Upon stabilization, placement of a pulmonary artery (PA) catheter may be indicated based on the need for more extensive cardiovascular monitoring than is available from non-invasive measurements such as vital signs, cardiac rhythm, and urine output.9,10 Key measured parameters that can be obtained from a PA catheter are the pulmonary artery occlusion pressure, which is a measure of preload, and CO. From these values and simultaneous measurement of HR and blood pressure (BP), one can calculate the left ventricular SV and SVR.10 Placement of a PA catheter should be reserved for patients at high risk of death due to the severity of shock or preexisting medical conditions such as heart failure.11 Use of PA catheters in broad populations of critically ill patients is somewhat controversial because clinical trials have not shown consistent benefits with their use.12-14 However, critically ill patients with a high severity of illness may have improved outcomes from PA catheter placement. It is not clear why this was... 

The National Institutes of Health (NIH) has characterized "[t]he general aim of metabolomics. .. to identify, measure and interpret the complex, time-related concentration, activity and flux of endogenous metabolites in cells, tissues and other biosamples such as blood, urine and saliva."3 Taken together, the three "omics" disciplines represent a systemic and powerful approach to mapping cellular networks, allowing for faster and more predictive biology in terms of risk assessment, potential therapeutic benefit, as well as diagnosis. 

There is little credible scientific information available on the susceptibility and toxicological effects of 1,4-dichlorobenzene in children. The risk for exposure is apparently high. A study by Hill et al. (1995) measured blood levels of 1,4-dichlorobenzene and urine levels of its metabolites in 1,000 adults, finding that exposure to 1,4-dichlorobenzene was widespread, with 98% of the adults having measurable concentrations of 1,4-dichlorobenzene metabolites in their urine. There is no evidence to indicate that children are likely to be exposed to lower amounts of 1,4-dichlorobenzene from everyday living, suggesting that children are perhaps equally at risk for exposure and potential toxic side-effects. 

In vivo, measuring bile acids in plasma and urine should be revived as potential biomarkers in the modern metabolomic era. Then the first-order scientific question will become whether early and time-controlled fasting-level measurement of bile acid concentration in plasma and urine can become a sensitive and specific biomarker for drug-induced cholestasis and ultimately liver injury at later time-points [117] Clinical trials should be conducted to evaluate whether such bile acid measurements can be used as part of a predictive panel to identify patients who are at increased risk of drug-induced cholestasis. 

The ability to generate new biomonitoring data often exceeds the ability to evaluate whether and how a chemical measured in an individual or population may cause a health risk or to evaluate its sources and pathways for exposure. As CDC states in its National Reports on Human Exposure to Environmental Chemicals, the presence of a chemical in a blood or urine specimen does not mean that the chemical causes a health risk or disease. The challenge for public-health officials is to understand the health implications of the biomonitoring data, to provide the public with appropriate information, and to craft appropriate public-health policy responses. 

The widespread use of biomonitoring, as evidenced by reports citing chemical concentrations in human blood samples (CBRC 2005 IC Wales 2005 WWF 2002, 2003) or in initiatives for developing biomonitoring programs in such states as California and Minnesota (OMB Watch 2005 Risk Policy Report 2005), stems from improvement in analytic methods and laboratory techniques. It is possible to measure smaller concentrations of chemicals in the body and to do so with smaller quantities of biologic samples (such as blood and urine). 

In the most straightforward risk-based approach, epidemiologic studies have developed exposure-response relationships based on biomarker measurements in hair, blood, urine, or other matrices (e.g., mercury, lead) (see Figure 5-2a). The relationships can be applied directly to new biomonitoring data to determine where on the exposure-response curve any person is. That may facilitate an understanding of risk, but it does not analyze sources of exposure, so other techniques (such as environmental sampling and behavioral surveys) may be needed to assess where the exposure came from. 

The various microbial systems used to test blood and urine are useful measures of mutagenic exposure. Positive results cannot be interpreted in terms of health risk, but negative results can be reassuring. These tests are especially useful in monitoring occupational exposure, because such exposure is discovered promptly. Analysis of body fluids should be used in all situations in which positive results are interpreted as indexes of exposure. 

Current biomarkers for Alzheimer s disease include 8-amyloid, measured in cerebrospinal fluid Tau protein, measured in cerebrospinal fluid and neural thread protein/AD7C-NTP, measured in cerebrospinal fluid and in urine. In Alzheimer s patients, cerebrospinal fluid usually contains a reduced level of 42-aminoacid /8-amyloid and an increase in Tau protein. Such biomarkers are however unreliable they are not accurate for a diagnosis of Alzheimer s, because the same pattern findings are also found in other conditions. At present the costs involved in mass or individual screening would be high the procedures are also invasive, uncomfortable and not without additional risk. 

A study in Washington State found that children living with agricultural workers and in proximity to tree fruit orchards may have more opportunity for exposure than children living in homes without such risk factors (Simcox et al., 1995). These findings were supported by an additional study which measured pesticide metabolites in children s urine (Loewenherz et al., 1997 Lu et al., 2000). 

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