Anaesthetics, local detection

Stalberg, O., Sander, K., and Sanger-van de Griend, C. (2002). The determination of bromide in a local anaesthetic hydrochloride by capillary electrophoresis using direct UV detection.. Chromatogr. A 977, 265-275. 

VerUcchi et al. [36] found that antibiotics, analgesics/anti-inflammatories and steroid compounds are the therapeutic classes most abundantly administered in Italian hospitals, but consistent consumption of cardiovascular compounds, tranquilizers, anti-neoplastics and anaesthetics was also detected. According to other authors in other localities [32, 41], PhCs detected in the largest amounts in hospital effluents are antibiotics, anti-epUeptics, beta-blockers, Upid regulators and... 

Ester and amide local anaesthetics differ in the manner, site and rate of metabolism. There is little relation between the elimination of local anaesthetics and their duration of action. Amethocaine has a prolonged action due to its high affinity for nerve tissue despite being rapidly removed from plasma. Bupivacaine can be detected in the plasma many hours after its effects have worn off due to continuing absorption from the site of injection. The renal excretion of unchanged local anaesthetics is minimal. 

Chloroethane is produced by the hydrochlorination of ethylene. It is used in the manufacture of tetraethyllead, as an industrial ethylating agent, as a blowing agent in the production of polystyrene foam and as a local anaesthetic. Occupational exposure occurs during the production of tetraethyllead, and industrial emissions have led to detectable levels of chloroethane in ambient air (lARC, 1991). 

Fig. 8-85. Analysis of sulfite in a local anaesthetics. — Separator column IonPac AS9 eluent 0.00075 mol/L NaHC03 + 0.002 mol/L Na X flow rate 2 mL/min detection suppressed conductivity injection 50 pL sample (diluted 1 10).

Anions—direct detection Quantitative determination of alginic acid in pharmaceutical formulatioDS Determination of residual Br in excess of chloride for local anaesthetic analysis Arginine counterion determination for ragaglitazone... 

The leucocyte histamine release test (referred to in greater detail in Chaps. 1-7) is one of the in vitro correlates of immediate allergy which may find useful application in investigating reactions to local anaesthetics. It is of some value in detecting acute reactions, whether they are truly anaphylactic or due to direct (non-immune) histamine release (anaphylactoid). It is also more accurate (quantitative), more reliable and more predictive than skin tests, and above all it is free from risk. 

Capsaicin is the pungent principle derived from fruits of cayenne pepper—Capsicum annum, C. frutescens (Solanaceae). Capsaicin, a phenolic amide, is present in the fruit at a level of only 0.02%, yet its taste is detectable even in minute doses. The compound acts as a local anaesthetic and pain reliever through a complex mechanism (see Chapter 8). 

Alkamides can be readily detected by organoleptic means, by placing a very small quantity on the tongue. The initial sharp sensation and saliva production is followed by a local anaesthetic or numbing effect. Not surprisingly many are associated with management of toothache—Spilanthes and Zanthoxylum spp. are both known in their respective regions as toothache plant . 

Lombardo-Aghi M, Cruces-Bianco C, Garcfa-Campana AM (2009) Capillary zone electrophoresis with diode-array detection Iot the analysis of local anaesthetics and opium alkaloids in urine samples. J Chromatogr B Analyt Technol Biomed Life Sci 877(8-9) 833-836... 

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