Electrodes dexamethasone

Commercially available electrotransport systems are bulky and limited to acute appHcations (96). One example, the Drionic system used for the treatment of hyperhidrosis (excessive perspiration), is presoaked in water for 30 min before each 20- to 30-min treatment. Another system, the Phoresor, approved for the deHvery of Hdocaine [137-58-6] for local anesthesia, and of dexamethasone [50-02-2] for treatment of local inflammation such as bursitis or tendinitis, is powered by a 9 V replaceable battery and features a disposable, fiHable dmg electrode. 

Paracetamol, furosemide, dipyrone, cefazolin and dexamethasone/urine DPV Working electrode HMDE and graphite Reference electrode Ag/Ag/Cl Supporting electrolyte Britton-Robinson buffer (pH 2.4) Extraction SPE/column SPE NH2/elution MeOH Extraction LLE/ethyl acetate LOD 0.20-2.57 pM LOQ 0.53-6.28 pM [86]... 

Iontophoresis in the ear to relieve pain was reported by Albrecht in 1911 [47]. He used cocaine in high concentrations (20%-40%), copper electrodes, and uncontrolled high current (1.5-2 mA) on perforated tympanic membranes. Despite excellent anesthesia, many of his patients were vertiginous during and after treatment, with some patients suffering permanent loss of hearing. However, relatively recent studies have demonstrated that the use of lidocaine [48], A-acetylcysteine [49], or dexamethasone and fosfomycin [50] in iontophoresis to the ear has no adverse effects in either animal or clinical trials. Echols et al. [51] confirmed that lidocaine could be iontophoresed in the middle ear for at least 30 minutes at 1 mA without any adverse effects. 

Dexamethasone CE Counter Electrode e Anion WE Working Electrode... 

Another major breakthrough in lead design is the steroid-eluting electrode (Figure 11.12). About 1 mg of a corticosteroid (dexamethasone sodium phosphate) is contained in a silicone core that is surrounded by the electrode material. The leaking of the steroid into the myocardium occurs slowly over several years and reduces the inflammation that results from the lead placement. It also retards the growth of the fibrous sack that forms around the electrode, which separates it from viable myocardium. As a result, the dramatic rise in acute thresholds that is seen with nonsteroid leads during the 8-16 weeks postimplant is nearly ehminated. 

Wadhwa, R., Lagenaur, C.F., Cui, X.T., 2006. ElectrochemicaUy controlled release of dexamethasone from conducting polymer polypyrrole coated electrode. J. Controlled Release 110,531-541. 

P-wave amplitudes than their non-drug-eluting counterpart [10, 11]. Another type of drug-eluting lead is designed with a porous ceramic or silicone collar soaked with dexamethasone sodium phosphate positioned immediately proximal to tip electrode. This system is used in steroid-eluting, active fixation screw-in leads and shows similar performance as the MCRD. Steroid elution is available on atrial and ventricular leads and as well as coronary venous and epicardial leads. 

Fig. 1.16 Steroid-eluting electrode. Le/l Cross sectional diagram demonstrating the silicone rubber plug impregnated with dexamethasone sodium phosphate lying immediately behind the porous electrode and connected to it by a channel. Right Tined lead with a platinized platinum porous, steroid-eluting electrode. (Permission for use Medtronic.)...

Although dexamethasone sodium phosphate has been the most widely used glucocorficosteroid in steroid-eluting pacing electrodes, more recently dexamethasone acetate, originally proposed in 1991 (39), has also been... 

Beclomethasone has also been suggested as a glucocorticosteroid for pacemaker electrode use. Being much more potent than the dexamethasone salts, smaller doses could be used. To date, beclomethasone has been applied directly to the screw electrode of very thin leads, where traditional steroideluting devices are not practical. 

Radovsky AS, Van Vleet JF. Effects of dexamethasone elution on tissue reaction around stimulating electrodes of endocardial pacing lead in dogs. Am Heart J 1989 117 1288-1298. 

Lepiince, L., Dogimont, A., Magnin, D., Demoustier-Champagne, S. (2010). Dexamethasone electrically controlled release from polyp5nrole-coated nanostructured electrodes. Journal of Materials Science Materials in Medicine, 21(3), 925-930. 

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