Liver monitoring

Liver monitoring necessary Rarely used any more, given hepa-totoxic concerns... 

The liver performs a stunning variety of metabolic activities. In addition to its key roles in carbohydrate, lipid, and amino acid metabolism, the liver monitors and... 

Acid- and alkaline phosphatases act on a variety of mono- and multiple phosphate carrying low molecular mass molecules. In addition, they hydrolyze many, but not all, phosphoproteins. They are in use for decades to easily screen for diseases, however, somewhat unspe-cifially. For instance, acid phosphatase is used as biomarker for prostate cancer, and alkaline phosphatase to monitor bone (de-) mineralization and liver tumors. 

The elimination of drag s from the body is called excretion. After the liver renders drag s inactive, the kidney excretes the inactive compounds from the body. Also, some dragp are excreted unchanged by the kidney without liver involvement. Fhtients with kidney disease may require a dosage reduction and careful monitoring of... 

It is important to monitor closely serum blood levels of chloramphenicol, particularly in patients with impaired liver or kidney function or when administering chloramphenicol with other drugs metabolized by the liver. Blood concentration levels exceeding 25 mcg/mL increase the risk of the patient developing bone marrow depression. 

ISONIAZID. Severe and sometimes fatal hepatitis may occur with isoniazid therapy. The nurse must carefully monitor all patients at least monthly for any evidence of liver dysfunction. It is important to instruct patients to report any of tlie following symptoms anorexia, nausea, vomiting, fatigue, weakness, yellowing of Hie skin or eyes, darkening of Hie urine, or numbness in the hands and feet. 

Older adults are particularly susceptible to a potentially fatal hepatitis when taking isoniazd, especially if they consume alcohol on a regular basis. Two other antitubercular drugs rifampin and pyrazinamide, can cause liver dysfunction in the older adult. Careful observation and monitoring for signs of liver impairment are necessary (eg, increased serum aspartate transaminase, increased serum alanine transferase, increased serum bilirubin, and jaundice). 

PYRAZINAMIDE Patients should have baseline liver functions tests to use as a comparison when monitoring liver function during pyrazinamide therapy. The nurse should monitor the patient closely for symptoms of a decline in hepatic functioning (ie, yellowing of the skin, malaise, liver tenderness, anorexia, or nausea). The primary health care provider may order periodic liver function tests. Hepatotoxicity appears to be dose related and may appear at any time during therapy. 

ITRACONAZOLE Although rare, die patient may develop hepatitis during itraconazole administration. The nurse closely monitors die patient for signs of hepatitis, including anorexia, abdominal pain, unusual tiredness, jaundice, and dark urine. The primary healtii care provider may order periodic liver function tests. 

MTX is potentially toxic. Therefore, the nurse observes closely for development of adverse reactions, such as thrombocytopenia (see Nursing Alert in Gold Compounds section) and leukopenia (see discussion of adverse reactions associated with hydroxychloroquine). Hematology, liver, and renal function studies are monitored every 1 to 3 months with MTX therapy. The primary care provider is notified of abnormal hematology, liver function, or kidney function finding. The nurse immediately brings all adverse reactions or suspected adverse reactions to the attention of the primary health care provider. 

A serious and potentially fatal adverse reaction to tolcapone ishepatic injury. Regular blood testing to monitor liver function is usually prescribed. The phys dan may order testing of serum transaminase levels at frequent intervals(eg, every 2 weeks for the first year and every 8 weeks thereafter). Treatment is discontinued if the ALT (SOFT) exceeds the upper normal limit or sgns or symptoms of liver failure develop. 

When administering tacrine, the nurse must monitor the patient for liver damage. This is best accomplished by monitoring alanine aminotransferase (AIT) levels. ALT is an enzyme found predominately in the liver. Disease or injury to the liver causes a release of tiiis enzyme into the bloodstream, resulting in elevated ALT levels, hi patients taking tacrine, ALT levels should be obtained weekly from at least week 4 to week 16 after die initiation of tiierapy. After week 16, transaminase levels are monitored every 3 months. 

When administering the HMG-CoA reductase inhibitors and the fibric acid derivatives, the nurse monitors the patient s fiver function by obtaining serum transaminase levels before the drug regimen is started, at 6 and 12 weeks, then periodically thereafter because of the possibility of liver dysfunction with the drugs. If aspartate aminotransferase (AST) levels increase to three times normal, the primary care provider in notified immediately because the HMG-CoA reductase inhibitor therapy may be discontinued. 

ASSESSMENT OF THE HOSPITALIZED PATIENT The hospitalized patient receiving a female hormone requires careful monitoring. The nurse takes the vital signs daily or more often, depending on the patient s physical condition and the reason for drug use. The nurse observes the patient for adverse drug reactions, especially those related to the liver (the development of jaundice) or the cardiovascular system (thromboembolism). The nurse weighs the patient weekly or as ordered by the primary health care provider. The nurse... 

FAT EMULSIONS. When a fat emulsion is administered, the nurse must monitor the patient s ability to eliminate the infused fat from the circulation. The lipidemia must clear between daily infusions. The nurse monitors for lipidemia through assessing the result of the following laboratory exams hemogram, blood coagulation, liver function tests, plasma lipid profile, and platelet count. The nurse reports an increase in any of these laboratory examinations as abnormal. 

Worldwide, 15 million HBsAg carriers are also infected with hepatitis D/delta virus (HDV) (Gaeta et al. 2000). This situation represents a major therapentic challenge, as most of these patients have advanced liver disease, inclnding cirrhosis in 60-70% of cases, and hepatocellular carcinoma (Fattovich et al. 2000 Saracco et al. 1987). No specific HDV inhibitors have been developed, and IFN-a-based treatment is more difficnlt in HBV-HDV infection than in HBV monoinfection. HDV RNA levels in sernm can be nsed to monitor treatment efficacy. The endpoint of therapy is HDV RNA clearance and ALT normalization, and this is sometimes achieved after the end of treatment. A snstained response can lead to HBsAg clearance from serum. 

One study conducted in Britain between 1983 and 1989 was of barn owls found dead in the field 10% of the sample of 145 birds contained anticoagulant rodenticide residues in their livers, and difenacoum and brodifacoum were prominent among them (Newton et al. 1990). In another study, barn owls were fed rats that had been dosed with flocoumafen. It was found that a substantial proportion of the rodenticide ingested by owls was eliminated in pellets (Eadsforth et al. 1991). The authors suggest that exposure of owls to rodenticides in the field may be monitored by analysis of pellets dropped at roosts or regular perching places. 

Figure 2.17 Application of the reverse DEPT pulse sequence to monitor C-labeled glucose by mouse liver-cell extract. (A) Normal FT spectrum. (B) Reverse DEPT spectrum showing the a- and )3-anomeric proton resonances. (C) Two different CH2 proton resonances, a and b, appear after 1.5 h of metabolism. (D) Edited H spectrum confirming that the CH2 resonances arise from metabolic products. (Reprinted from J. Magn. Resonance 56, Brooks et al., 521, copyright 1984, Academic Press.)...

Applying the reverse DEPT pulse sequence to monitor C-labeled glucose by mouse liver-cell extract is shown in Fig. 2.17. The a- and /3-anomeric proton resonances are shown in the starting material these are transformed to CH.2 proton resonances in the metabolite. 

Another common liver disease, alcoholic liver damage produced by moderate to heavy alcoholic intake, is also reflected by an elevation of the serum GOT and GPT activities. The serim glutamyl transferase activity is reported to be a sensitive index of alcoholic intake and can serve to monitor persons on alcoholic withdrawal programs (60). The LD-5 isoenzyme arises mainly from liver tissue, but has a short half-life (61), which is about 1/5 and 1/2 of the half life of the transaminases, GPT and GOT respectively. Some authors consider that a normal LD-5 isoenzyme activity in a jaundiced patient is sufficient evidence to exclude primary liver disease and that obstruction is probably responsible for the jaundice (62). In hemolytic jaundice the LDH-1 and 2 isoenzymes are elevated. 

This approach can be used only for fat-soluble compounds that follow the same lymphatic route to be transported to the liver as carotenoids. The bioavailability of the compound of interest is determined by monitoring the appearance of the compound and its newly formed intestinal metabolites in the postprandial chylomicron fraction of plasma [also called the density < 1.006 kg/L fraction or triglyceride-rich lipoprotein (TRL) fraction because it is generally a mixture of chylomicrons (CMs) and very low density lipoproteins (VLDLs)] as a function of the time after ingestion. 

Burger J, Lord CG, Yurkow EJ, McGrath L, Gaines KF, Brisbin Jr IL, Gochfeld M. 2000b. Metals and metallothionein in the liver of raccoons utility for environmental assessment and monitoring. J Toxicol Environ Health A 60 243-261. 

This selected ion monitoring (SIM) approach typically has greater applicability in cases where sensitivity is more of a concern. Kiehl and Kennington developed a swine liver confirmatory method for tilmicosin that confirmed structure based upon monitoring a parent ion and two additional structural fragment ions. A discussion of the validation requirements for confirmatory methods is provided in Section 6. 

Monitor for adequate perfusion of vital organs through assessment of mental status, creatinine clearance, liver function tests, and a stable HR between 50 and 100 beats per minute. Additionally, adequate skin and muscle blood perfusion and normal pH is desirable. 

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