PH monitoring

Implement pH monitoring to determine useful life of scrubbing solution... 

More definitive diagnostic tests include endoscopy (via endoscope or Pillcam ESO capsule), 24-hour ambulatory pH monitoring, diagnostic proton pump inhibitor (PPI) administration, or esophageal manometry. 

Hour ambulatory pH monitoring may be the only way to objectively prove that symptoms are reflux-related in patients with atypical symptoms or non-erosive reflux disease. Ambulatory pH monitoring may also be useful in patients whose symptoms are not improving on adequate doses of acid-suppressing therapy. 

The empiric use of a standard-dose (or double-dose) PPI as a therapeutic trial may be used in diagnosing GERD. This approach is less expensive, more convenient, and more readily available than ambulatory pH monitoring. Problems with this diagnostic approach include lack of a standardized dosing regimen and duration of the diagnostic trial. 

Hour ambulatory pH monitoring A test that quantifies the amount of acid that refluxes into the esophagus over 24 hours under ambulatory (outpatient) conditions. 

Suidan J.S., Young B.K., Hetzel F.W., Seal H.R., pH Measurement with a fiber-optic tissue-pH monitor and a standard blood-pH meter, Clin. Chem. 1983 29 1566. 

Figure 2. Optode with phenol red bound to polyacrylamide microsphere for blood pH monitoring.

A different approach was also described22 a fibre optic blood gas and pH monitoring system, capable of performing "paracorporeal" measurements for... 

For pH sensors used in in-vivo applications, especially those in continuous pH monitor or implantable applications, hemocompatibility is a key area of importance [150], The interaction of plasma proteins with sensor surface will affect sensor functions. Thrombus formation on the device surface due to accelerated coagulation, promoted by protein adsorption, provided platelet adhesion and activation. In addition, variation in the blood flow rate due to vasoconstriction (constriction of a blood vessel) and sensor attachment to vessel walls, known as wall effect , can cause significant errors during blood pH monitoring [50, 126],... 

In addition to glass electrodes [159], the pH sensors incorporated in the catheter for esophageal pH monitoring were reported to be mostly antimony electrodes such as the Slimline from Medtronic Inc. [95, 158, 164], In a recent study, Pandolfino el al. [33] compared the accuracy of the Slimline antimony pH monitoring system to that of a conventional glass electrode catheter pH system during ambulatory conditions in 18 patients. They reported that the antimony electrodes had acceptable performance... 

A. Jabre, Y. Bao, and E.L. Spatz, Brain pH monitoring during ischemia. Surg. Neurol. 54, 55-58... 

Y. Vandenplas, H. Badriul, M. Verghote, B. Hauser, and L. Kaufman, Oesophageal pH monitoring and reflux oesophagitis in irritable infants. EurJ. Pediatr. 163, 300-304 (2004). 

P.J. Kahrilas and J. Pandolfino, Oesophageal pH monitoring — technologies, interpretation and correlation with clinical outcomes. Alimentary Pharmacol. Therapeutics 22, 2—9 (2005). 

S. Harrell, B. Evans, S. Goudy, W. Winstead, E. Lentsch, J. Koopman, and J.M. Wo, Design and implementation of an ambulatory pH monitoring protocol in patients with suspected laryngopharyngeal reflux. Laryngoscope 115, 89—92. (2005)... 

A. Arana, B. Bagucka, B. Hauser, B. Hegar, D. Urbain, L. Kaufman, and Y. Vandenplas, pH monitoring in the distal and proximal esophagus in symptomatic infants. J. Pediatric Gastroenterol. Nutrition 32, 259-264 (2000). 

S.K. Ahlawat, DJ. Novak, D.C. Williams, K.A. Maher, F. Barton, and S.B. Benjamin, Day-to-day variability in acid reflux patterns using the BRAVO pH monitoring system. J. Clin. Gastroenterol. 40, 20-24 (2006). 

S.B. des Varannes, F. Mion, P. Ducrotte, F. Zerbib, P. Denis, T. Ponchon, R. Thibault, and J.P. Galmiche, Simultaneous recordings of oesophageal acid exposure with conventional pH monitoring and a wireless system (Bravo). Gut 54, 1682-1686 (2005). 

J.M. Remes-Troche, J. Ibarra-Palomino, R.I. Carmona-Sanchez, and M.A. Valdovinos, Performance, tolerability, and symptoms related to prolonged pH monitoring using the Bravo system in Mexico. Am. J. Gastroenterol. 100, 2382-2386 (2005). 

J.A. Hochman and T. Favaloro-Sabatier, Tolerance and reliability of wireless pH monitoring in children. Nutrition 41, 411-415 (2005). 

Fimmel CJ, Etienne A, Cilluffo T, Ritter C, Gasser T, Rey JP, et al Long-term ambulatory gastric pH monitoring Validation of a new method and effect of H2-antagonists. Gastroenterology 1985 88 1842-1851. 

Barium radiography is less expensive than endoscopy but lacks the sensitivity and specificity needed to accurately determine the presence of mucosal injury or to distinguish Barrett s esophagus from esophagitis. Twenty-four-hour ambulatory pH monitoring is useful in patients who continue to have symptoms without evidence of esophageal damage, patients who are refractory to standard treatment, and patients who... 

W. S. Kisaalitas, P. J. Slininger, R. J. Bothast, J. F. McCarthy, and R. L. Magin, Application of fiber-optic fluorescence measurements to on-line pH monitoring of a pseudomonad fermentation... 

The types of reaction for which pH monitoring is useful are as follows. The mode of monitoring, (a) or (b) above, will be determined by the rate. 

Aspiration study, oesophageal pH monitoring and bilirubin detection via optic fibre. OD Reading of 0.2 taken as threshold. N=25 controls, 53 GORD patients. 

Multi-channel intra-luminal impedance, coupled to pH monitoring. N 168 patients. 

Applications of fiber-optic pH sensors in environmental analysis, biomedical research, medical monitoring, and industrial process control have been reviewed by Lin [67]. A multitude of luminescent systems for pH monitoring are commercially available, mostly under special trademarks. Pyrene [68-70], coumarin, bromothymol blue [71] and fluorescein [72-74] derivatives are typical examples that have been used in research in the past two decades. Carboxyfluorescein derivatives have been directly applied to skin tissue samples for the lifetime imaging of pH gradients in the extracellular matrix of the epidermis [75]. Two-photon excitation microscopy became an estab-... 

The relationship between gastric residence time (GRT) and the variability in aspirin absorption from enteric-coated tablets has also been evaluated with the Heidelberg capsule [59], The study design was a single dose crossover study with men and women, fasted and fed. In addition to pH monitoring, plasma concentrations of salicylic acid and salicyluric acid in plasma and urine were measured. GRT was significantly delayed in the fed state, and women had longer GRT compared with men. 

Cherlet M, Marc A (1998), Intracellular pH monitoring as a tool for the study of hybridoma cell behavior in batch and continuous bioreactor cultures, Biotechnol. Prog. 14 626-638. 

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