Percutaneous

Percutaneous Hver biopsy after each 1.5 g of total accumulated methotrexate dosage to detect hepatic fibrosis or cirrhosis not rehably predicted by semm aminotransferase tests are recommended (1,50). Concurrent use of NSAIDs may increase toxicity of methotrexate, although toxicity may be avoided if the dmgs are separated by 12 h. 

Toxicity. No mortahty in laboratory animals was induced in percutaneous doses up to 3.8 g/kg body weight (19,20). Subcutaneous adininistration of sulfolane gives LD q values for rats, mice, and rabbits of 1.606, 1.360, and 1.900—3.500 g/kg body weight, respectively (21). LD q values... 

Skin. The skin may become contaminated accidentally or, in some cases, materials may be deHberately appHed. Skin is a principal route of exposure in the industrial environment. Local effects that are produced include acute or chronic inflammation, allergic reactions, and neoplasia. The skin may also act as a significant route for the absorption of systemicaHy toxic materials. Eactors influencing the amount of material absorbed include the site of contamination, integrity of the skin, temperature, formulation of the material, and physicochemical characteristics, including charge, molecular weight, and hydrophilic and lipophilic characteristics. Determinants of percutaneous absorption and toxicity have been reviewed (32—35,42,43,46—49). 

The toxicity of a few boric acid esters has been summarized (30). In general the toxicities are directiy related to the toxicity of the alcohol or phenol produced on hydrolysis. Methyl borate has an oral rat LD q of 6.14 mL/kg in a range finding test (31) and the percutaneous LD q for the rabbit of 1.98 mL/kg. In eadier work (32), the oral LD q for the rat was 2.82 mL/kg the intraperitoneal LD q was 3.2 mL/kg. It has been shown that the mouse is more susceptible to these compounds than the rat. Methyl borate was found to be moderately irritating in an ocular toxicity test using rabbits (31,32) but only mildly irritating to skin (31). 

VX (6,7) is estimated to be about three times as potent a respiratory agent as sarin (GB) but about a hundred times as potent as a percutaneous... 

The mechanisms that control dmg deUvery from pumps may be classified as vapor-pressure, electromechanical, or elastomeric. The vapor-pressure controlled implantable system depends on the principle that at a given temperature, a Hquid ia equiUbrium with its vapor phase produces a constant pressure that is iadependent of the enclosing volume. The two-chamber system contains iafusate ia a flexible beUows-type reservoir and the Hquid power source ia a separate chamber (142). The vapor pressure compresses the dmg reservoir causiag dmg release at a constant rate. Dmg maybe added to the reservoir percutaneously via a septum, compressing the fluid vapor iato the Hquid state. 

PERCUTANEOUS ABSORPTION Absoi ption via the skin, e.g. due to local contamination or a splash of chemical. 

Riihimaki, V. (1979), Percutaneous absorption of iB-xylene from a mixture of m-xyleiie and isobutyl alcohol in man. Scand. ]. Work Environ. Health 5, 14,3-150,... 

A percutaneous catheter procedure that inflates a balloon in areas of narrowing (stenosis) in arteries. 

GPIIb/IIIa antagonists have to be administered parenterally. They are currently used prophylactically during intracoronary interventions such as percutaneous transluminal revascularization with balloon angioplasty or intracoronary stenting, as well as to treat acute coronary syndromes like unstable angina and acute myocardial infarction. The main complications... 

Percutaneous coronary intervention (PCI) is one of a host of techniques performed by using a catheter inserted via a major limb artery that aims to relieve nanowing of coronary arteries. For example, percutaneous transluminal coronary angioplasty (PTCA) is the classic PCI that uses a catheter-directed balloon to dilate a stenotic coronary artery, and more recent PCIs include stent implantation, rotational atherectomy, and laser angioplasty. 

Access to the epidural route is made through the use of a percutaneous epidural catheter. The placement of the catheter requires strict aseptic technique by a skilled physician. The epidural catheter is placed into the space... 

Alcohol and alcohol ether sulfates have also been studied to determine their toxicity by percutaneous absorption in rats and guinea pigs [354-356]. Alcohol ether sulfates penetrate in the order of 1 ng/cm2/day and alcohol sulfates are less penetrant by a factor of 10. The surfactant absorbed was metabolized. Since it is known that human skin is less permeable than animal skin, only very small amounts of alcohol or alcohol ether sulfates can be absorbed even in the case of complete body exposure. 

Taking into account the low oral toxicity and the low intestinal and percutaneous absorption of alcohol sulfates and alcohol ether sulfates, the possibility of systemic toxic effects in humans is extremely unlikely [344]. 

Bergstrom, M. Hultman. E. (1990). Contraction characteristics of the human quardriceps muscle during percutaneous electrical stimulation. Pflugers Arch. 417, 136-141. 

Galal EE, Latif MA, Kandil A, et al. 1975. The percutaneous cardiac toxicokinesis of anticholinesterase insecticides. J Drug Res 7 29-43. 

Sartorelli P, Aprea C, Bussani R, et al. 1997. In vitro percutaneous penetration of methyl-parathion from a commercial formulation through the human skin. Occup Environ Med 54 524-525. 

This approach has been used primarily in Japan to treat patients with malignant, inoperable hepatic cancer. Mitomycin C contained in albumin microspheres was administered to patients (122) by percutaneous intraarterial catheterization. Tumor reduction was seen in over 68% of the cases. By contrast, the control group, receiving infusion therapy, had a poorer response. Survival times were also greater for patients receiving the microspheres. 

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