Comparison of propofol deep sedation versus moderate sedation during endosonography.

BACKGROUND: The purposes of this study are: (1) to prospectively evaluate clinically relevant outcomes including sedation-related complications for endoscopic ultrasound (EUS) procedures performed with the use of propofol deep sedation administered by monitored anesthesia care (MAC), and (2) to compare these results with a historical case-control cohort of EUS procedures performed using moderate sedation provided by the gastrointestinal (GI) endoscopist. MATERIALS AND METHODS: Patients referred for EUS between January 1, 2001 and December 31, 2002 were enrolled. Complication rates for EUS using MAC sedation were observed and also compared with a historical case-control cohort of EUS patients who received meperidine/midazolam for moderate sedation, administered by the GI endoscopist. Logistic regression analysis was used to isolate possible predictors of complications. RESULTS: A total of 1,000 patients underwent EUS with propofol sedation during the period from January 1, 2001 through December 31, 2002 (mean age 64 years, 53% female). The distribution of EUS indications based on the primary area of interest was: 170 gastroduodenal, 92 anorectal, 508 pancreaticohepatobiliary, 183 esophageal, and 47 mediastinal. The primary endpoint of the study was development of sedation-related complications occurring during a performed procedure. A total of six patients experienced complications: duodenal perforation (one), hypotension (one), aspiration pneumonia (one), and apnea requiring endotracheal intubation (three). The complication rate with propofol was 0.60%, compared with 1% for the historical case-control (meperidine/midazolam moderate sedation) group. CONCLUSIONS: There does not appear to be a significant difference between complication rates for propofol deep sedation with MAC and meperidine/midazolam administered for moderate sedation.

A screening procedure for total N-nitroso contaminants in personal care products: results of collaborative studies undertaken by a CTPA Working Group.

Synopsis A modified procedure for the determination of total N-nitroso compounds in personal care products was evaluated in collaborative studies organized through the UK Cosmetic Toiletry and Perfumery Association (CTPA). The method offers a true 'totals'determination in that a solution of the whole sample is analysed. Samples are dissolved/suspended in water or aqueous THF, and nitrite/nitrite ester interferences are removed by prior treatment with sulphamic acid. The treated test solution is denitrosated in a single reaction with HBr/acetic acid, in refluxing n-propyl acetate, and 'total'N-nitroso compounds are determined in a chemiluminescence reaction of the released nitric oxide with ozone. The use of a propyl acetate denitrosation solvent and of higher concentrations of HBr have improved both the sensitivity (routine limit of determination at 10 mugkg(-1)) and water tolerance of the method. The method was shown to recover N-nitrosamines quantitatively, and to be sufficiently repeatable and reproducible to be used as a screening technique for N-nitroso compounds in personal care products.

Reduction of nitrosamines in cosmetic products.

Summary From initial rate studies of morpholine nitrosation in aqueous media by nitrite ion in the presence of formaldehyde at pH 5-7 and 25 degrees C, four potential pathways are revealed for the concurrent formation of nitrosamine contaminants in cosmetic and toiletry products. Three of the pathways involve conventional electrophilic nitrosation by XNO reagents of both neutral amine and N-hydroxymethylamine compounds obtained by prior reaction with formaldehyde. The fourth pathway involves a nucleophilic reaction by nitrite ion with the iminium ion derived from N-hydroxymethylamine. For morpholine, reaction via XNO reagents is substantial at pH 5 only, whereas the iminium ion pathway is pre-eminent at pH 7. The concurrent formation of nitrosamines by mechanistically different pathways implies that combinations of nitrosation inhibitors are necessary to minimize contamination of cosmetic and toiletry products. For these different pathways, novel inhibitory compounds are described which fulfil the usual acceptance criteria for cosmetic and toiletry materials. The efficacy of these compounds is assessed against N-nitrosomorpholine formation in the presence of formaldehyde. These include erythorbate, ascorbate, pentanedione and pyranone compounds for the XNO pathways (pH 6) and neutral organic and inorganic salts for the iminium ion pathways (pH 7). Preliminary results for both a bath gel and a cream-base formulation deliberately adulterated with morpholine, diethanolamine, nitrite and a preservative which releases low levels of formaldehyde on decomposition show better than 90% inhibition of nitrosamines by selected pairs of inhibitor compounds on storage at 40 degrees C over several months. This novel technology is the subject of a worldwide patent application.