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1.
J Intellect Disabil Res ; 60(11): 1066-1072, 2016 11.
Article in English | MEDLINE | ID: mdl-26939804

ABSTRACT

BACKGROUND: Guidelines for the safe administration of drugs through enteral feeding tube (EFT) are an important tool to minimise the risk of errors. This study aimed to investigate knowledge of these guidelines among staff of residential care facilities (RCF) for people with ID. METHOD: Knowledge was assessed using a 13-item self-administered questionnaire. Questions reflected key aspects of guidelines on medication administration via EFT. All staff members that administer medication through EFT in Belgian RCFs were invited to participate (n = 553). RESULTS: Nine out of 10 RCFs participated, and 356 questionnaires were collected. Almost all participants were women (96%), and most (82%) had a non-nursing educational background. Mean self-perceived knowledge of medication administration via EFT was 6.7 (on a 0-10 scale). On average, 5.7 (SD 1.9) out of 13 questions were answered correctly. A nursing degree and previous education on medication administration via EFT were associated with significantly higher scores. Guideline recommendations regarding rinsing of used medicine cups (90% correct answers) and preparation of hard gelatin capsules (89%) were known best. Those regarding the use of protective equipment when crushing toxic substances (4% correct answers), crushing of sustained release and enteric-coated dosage forms (6%), elevation of the patient's backrest (14%) and flushing of the EFT (15%) were known the least. CONCLUSION: This study identified a substantial lack of knowledge of guidelines for drug administration through EFT among staff of RCFs for people with ID. Our findings call for tailored educational programmes in order to increase knowledge on this subject.


Subject(s)
Drug Therapy/standards , Enteral Nutrition/standards , Health Knowledge, Attitudes, Practice , Health Personnel/standards , Intellectual Disability/drug therapy , Intellectual Disability/nursing , Nursing Staff/standards , Practice Guidelines as Topic/standards , Residential Facilities/standards , Adult , Female , Humans , Male , Middle Aged
2.
Int J Pharm ; 492(1-2): 1-9, 2015 Aug 15.
Article in English | MEDLINE | ID: mdl-26160667

ABSTRACT

The primary purpose of this study was to process partially hydrolyzed PVOH grades (degree of hydroxylation (DH): 33-88%) via HME and to evaluate them as carrier for oral immediate release dosage forms in order to improve the release rate of poorly water soluble drugs (i.e., HCT and CEL) via the formulation of solid dispersions. PVOH grades (DH >70%) were able to solubilize HCT and CEL up to 15%, but required higher extrusion temperature, due to the crystalline nature of PVOH. The highest drug release rate was observed from hot-melt extruded PVOH samples with a high DH. While drug release from extrudates consisting of PVOH with a low DH was affected by ionic strength, there was no influence of pH and ionic strength on HCT release from PVOH samples with a higher DH. However, PVOH (DH >70%) required higher extrusion temperatures, which could hamper its application for thermosensitive drugs. Therefore, the secondary purpose was to investigate the effect of sorbitol, a water-soluble plasticizer, on the thermal properties of hot-melt extruded PVOH (DH >70%). The melting of PVOH/sorbitol mixture was required to establish molecular interactions between PVOH and sorbitol. These molecular interactions were reflected in the HME behavior: whereas an extrusion temperature of 180 °C was necessary to process physical mixtures of PVOH (DH >70%) and sorbitol, only 140 °C was necessary during re-extrusion (after quench cooling and cryomilling) of the PVOH/sorbitol mixture. In addition, the in vitro and in vivo dug release of plasticized PVOH was examined; whereas the CEL/PVO/sorbitol system was able to maintain supersaturation during in vitro dissolution (0.1N HCl) compared to Celebrex(®), the in vivo pharmacokinetic parameters (AUC0-24h, Cmax and Tmax) were highly comparable.


Subject(s)
Drug Carriers/chemistry , Polyvinyl Alcohol/chemistry , Administration, Oral , Animals , Biological Availability , Celecoxib/blood , Celecoxib/chemistry , Celecoxib/pharmacokinetics , Dogs , Drug Carriers/pharmacokinetics , Drug Compounding , Drug Liberation , Hot Temperature , Hydrochlorothiazide/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Osmolar Concentration , Polyvinyl Alcohol/pharmacokinetics
3.
J Intellect Disabil Res ; 59(3): 215-25, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24762229

ABSTRACT

BACKGROUND: The administration of oral medication to patients with an enteral feeding tube (EFT) is challenging. Compliance to guidelines concerning medication administration via EFT has been investigated extensively in the hospital setting. However, studies in residential care facilities (RCFs) for individuals with intellectual disability (ID) are very limited. Therefore, the present study aimed to collect direct observational data on drug administration practices to residents with EFT in multiple RCFs. METHOD: This cross-sectional, observational study was conducted in six Belgian RCFs for individuals with ID. Observations of medication preparation and administration through EFT were carried out in two randomly selected units per participating RCF, on 2 days per unit during all daytime drug rounds, using a direct observation method. Afterwards, the recorded observations were compared with international guidelines on drug preparation and administration through EFT. RESULTS: In total, 862 drug preparations and 268 administrations in 48 residents with EFT were witnessed. Mixing together multiple drugs, not diluting liquid formulations with at least an equal amount of water, not shaking suspensions/emulsions before use, and not selecting the most appropriate dosage form were the most common deviations from medication preparation guideline recommendations. For medication administration, not flushing the EFT with at least 15 mL water was the most common deviation. We also observed high variability in working methods regarding medication preparation and administration via EFT, even between staff members of the same unit. CONCLUSION: This study found that current guidelines concerning medication preparation and administration through EFT are often not followed in Belgian RCFs for individuals with ID. Further research aimed at understanding why current guidelines are not followed seems warranted.


Subject(s)
Enteral Nutrition/standards , Intellectual Disability/nursing , Nursing Homes/standards , Practice Guidelines as Topic/standards , Adolescent , Adult , Child , Child, Preschool , Drug Administration Routes , Female , Humans , Intellectual Disability/drug therapy , Male , Middle Aged , Young Adult
4.
Eur J Pharm Biopharm ; 85(3 Pt B): 930-5, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23872178

ABSTRACT

In this study, febantel was dissolved under increased temperature in a nonionic surfactant Lutrol L44® and subsequently mixed into an aqueous maltodextrin solution. After 8h under static conditions, coacervation or phase separation took place. (1)H NMR spectra and HPLC analysis showed that the upper phase contained mainly all febantel, while no febantel was detected in the lower phase. Fluorescent microscopy showed that maltodextrin is distributed in the lower phase. Coacervation proved to be a promising formulation technology for certain poorly water-soluble drugs, such as febantel. The coacervate phase showed an increase in in vitro dissolution kinetics, compared to Rintal® granules. These results were confirmed in an in vivo study performed on dogs. Febantel and fenbendazole showed a significant increase in plasma concentration compared to Rintal® granules. Further studies have to be performed to transform coacervates into a solid dosage form and to prove broad applicability to other poorly soluble drugs.


Subject(s)
Chemistry, Pharmaceutical/methods , Guanidines/chemistry , Guanidines/chemical synthesis , Animals , Area Under Curve , Benzimidazoles/chemical synthesis , Biopharmaceutics/methods , Dogs , Drug Design , Fenbendazole/chemical synthesis , Guanidines/blood , Kinetics , Magnetic Resonance Spectroscopy , Microscopy, Fluorescence , Molecular Structure , Pilot Projects , Polyethylene Glycols/chemistry , Solubility , Surface-Active Agents , Temperature , Water/chemistry
5.
Food Chem Toxicol ; 57: 54-6, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23524315

ABSTRACT

Mycotoxins are toxic metabolites produced by fungi that readily colonize crops. After ingestion, these mycotoxins can compromise intestinal health, and once entering the blood stream, even affect the liver and its metabolizing enzymes. It was therefore the aim of the present study to investigate the effect of T-2 toxin, an emerging and potent Fusarium mycotoxin, on the enzymatic activity of cytochrome P4503A (CYP3A) metabolizing enzymes in the liver of pigs. In addition, a yeast-derived feed additive that claims to bind T-2 toxin was included in the study to evaluate its efficacy. Our results demonstrated that a 14-days intake of T-2 toxin contaminated feed at a dose of 903 µg/kg feed, whether or not combined with the mycotoxin binder, results in a substantial inhibition of the CYP3A activity in the liver of pigs. This result may be of importance for animal health, the pharmacokinetics and the withdrawal time of drugs that are substrate of CYP3A enzymes, and consequently can be a threat for public health with respect to tissue residues of these drugs.


Subject(s)
Cytochrome P-450 CYP3A Inhibitors , Liver/drug effects , T-2 Toxin/toxicity , Animal Feed , Animals , Food Contamination , Fusarium/chemistry , Liver/metabolism , Male , Swine
6.
Food Chem Toxicol ; 55: 150-5, 2013 May.
Article in English | MEDLINE | ID: mdl-23313610

ABSTRACT

The effects of the mycotoxin T-2 on hepatic and intestinal drug-metabolizing enzymes (cytochrome P450) and drug transporter systems (MDR1 and MRP2) in poultry were investigated during this study. Broiler chickens received either uncontaminated feed, feed contaminated with 68µg/kg or 752µg/kg T-2 toxin. After 3weeks, the animals were euthanized and MDR1, MRP2, CYP1A4, CYP1A5 and CYP3A37 mRNA expression were analyzed using qRT-PCR. Along the entire length of the small intestine no significant differences were observed. In the liver, genes coding for CYP1A4, CYP1A5 and CYP3A37 were significantly down-regulated in the group exposed to 752µg/kg T-2. For CYP1A4, even a contamination level of 68µg/kg T-2 caused a significant decrease in mRNA expression. Expression of MDR1 was not significantly decreased in the liver. In contrast, hepatic MRP2 expression was significantly down-regulated after exposure to 752µg/kg T-2. Hepatic and intestinal microsomes were prepared to test the enzymatic activity of CYP3A. In the ileum and liver CYP3A activity was significantly increased in the group receiving 752µg/kg T-2 compared to the control group. The results of this study show that drug metabolizing enzymes and drug transporter mechanisms can be influenced due to prolonged exposure to relevant doses of T-2.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP Binding Cassette Transporter, Subfamily B/metabolism , Cytochrome P-450 Enzyme System/metabolism , Diet , Intestines/drug effects , Liver/drug effects , T-2 Toxin/toxicity , Animals , Base Sequence , Biotransformation , Body Weight/drug effects , Chickens , DNA Primers , Intestinal Mucosa/metabolism , Intestines/enzymology , Liver/enzymology , Liver/metabolism , Polymerase Chain Reaction , ATP-Binding Cassette Sub-Family B Member 4
7.
J Vet Pharmacol Ther ; 36(6): 588-93, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23330986

ABSTRACT

Cytochrome P450 is involved in drug metabolism. Subfamily CYP3A shows a degree of similarity across different animal species. However, little information is available about its expression and activity in broiler chickens. A RT-PCR method was developed for the quantification of CYP3A37 expression in the liver and small intestine of broilers. A higher expression in the jejunum was observed compared with that in the ileum. In the liver, a significantly lower expression compared with that in the jejunum was noticed. Thus, the role of the small bowel in drug metabolism cannot be neglected in broilers. CYP3A activity was studied in vitro using midazolam as a substrate. Two protocols for the preparation of intestinal microsomes were compared. Mincing of the tissues before ultracentrifugation seemed to be more appropriate than a protocol based on ethylenediaminetetra-acetic acid separation. CYP3A activity revealed to be the highest in the duodenum with a decreasing trend towards the ileum. Activity in liver was comparable to duodenal activity.


Subject(s)
Aryl Hydrocarbon Hydroxylases/metabolism , Chickens , Gene Expression Regulation, Enzymologic/physiology , Intestines/enzymology , Liver/enzymology , Animals , Aryl Hydrocarbon Hydroxylases/genetics , Cytochrome P450 Family 3 , Female , Intestinal Mucosa/metabolism , Liver/metabolism , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism
8.
Drug Metab Dispos ; 39(11): 2066-75, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21832003

ABSTRACT

The aim of this study was to evaluate three different metabolite prediction software packages (Meteor, MetaSite, and StarDrop) with respect to their ability to predict loci of metabolism and suggest relative proportions of metabolites. A chemically diverse test set of 22 compounds, for which in vivo human mass balance studies and metabolic schemes were available, was used as basis for the evaluation. Each software package was provided with structures of the parent compounds, and predicted metabolites were compared with experimentally determined human metabolites. The evaluation consisted of two parts. First, different settings within each software package were investigated and the software was evaluated using those settings determined to give the best prediction. Second, the three different packages were combined using the optimized settings to see whether a synergistic effect concerning the overall metabolism prediction could be established. The performance of the software was scored for both sensitivity and precision, taking into account the capabilities/limitations of the particular software. Varying results were obtained for the individual packages. Meteor showed a general tendency toward overprediction, and this led to a relatively low precision (∼35%) but high sensitivity (∼70%). MetaSite and StarDrop both exhibited a sensitivity and precision of ∼50%. By combining predictions obtained with the different packages, we found that increased precision can be obtained. We conclude that the state-of-the-art individual metabolite prediction software has many advantageous features but needs refinement to obtain acceptable prediction profiles. Synergistic use of different software packages could prove useful.


Subject(s)
Pharmaceutical Preparations/metabolism , Pharmacokinetics , Software , Computer Simulation , Drug Synergism , Humans , Inactivation, Metabolic , Sensitivity and Specificity , Structure-Activity Relationship
9.
Article in English | MEDLINE | ID: mdl-18977186

ABSTRACT

The work presented here deals with the development of a quantitative tool for the determination of the quaternary ammonium anticholinergic glycopyrrolate in human plasma samples. Mepenzolate was used as an internal standard. The plasma samples were subjected to a suitable sample clean-up consisting of a simple and relatively fast, two step liquid-liquid ion-pair extraction procedure. The chromatography, using the same volatile ion-pair reagent heptafluorobutyric acid (HFBA), takes only 10 min. Relative standard deviation of retention times was never above 2.26% (n=36). The method was fully validated based on the US FDA Bioanalytical Method Validation Guidance for Industry. As such, a quantitative ESI-LC-MS(/MS) (TOF mass spectrometry) method was optimized for the absolute quantification of glycopyrrolate in human plasma in a concentration range from 0.101 to 101 ng/mL using a quadratic calibration function (R(2)=0.9995), y=-2.21 x 10(-4) (+/-3.93 x 10(-5))xx(2)+5.85 x 10(-2) (+/-5.27 x 10(-3))xx+4.08 x 10(-3) (+/-4.82 x 10(-4)). For the three QC concentrations (QC(1) 0.252, QC(2) 2.52, and QC(3) 25.2ng/mL) and the LLOQ (0.101 ng/mL), total precision was under 20% (18.0% (n=6) at the LLOQ) and maximum accuracy was 112% (88.9% for the LLOQ, n=6). Absolute matrix effect (maximum 133%+/-9.59, n=3), absolute recovery (better than 41.8%+/-2.22, n=3), relative (inter-subject) matrix effect (maximum 10.9%+/-1.45, n=4) and process efficiency (better than 45.2%+/-5.74, n=3) too were assessed at the 3 QC concentrations.


Subject(s)
Chemical Fractionation/methods , Chromatography, High Pressure Liquid/methods , Glycopyrrolate/blood , Spectrometry, Mass, Electrospray Ionization/methods , Humans , Reproducibility of Results , Tandem Mass Spectrometry/methods
10.
Article in English | MEDLINE | ID: mdl-16513414

ABSTRACT

An exploratory analysis was performed in order to evaluate the feasibility of building of neural network (NN) systems automating the identification of amphetamines necessary in the investigation of drugs of abuse for epidemiological, clinical and forensic purposes. A first neural network system was built to distinguish between amphetamines and nonamphetamines. A second, more refined system, aimed to the recognition of amphetamines according to their toxicological activity (stimulant amphetamines, hallucinogenic amphetamines, nonamphetamines). Both systems proved that discrimination between amphetamines and nonamphetamines, as well as between stimulants, hallucinogens and nonamphetamines is possible (83.44% and 85.71% correct classification rate, respectively). The spectroscopic interpretation of the 40 most important input variables (GC-FTIR absorption intensities) shows that the modeling power of an input variable seems to be correlated with the stability and not with the intensity of the spectral interaction. Thus, discarding variables only because they correspond to spectral windows with weak absorptions does not seem be not advisable.


Subject(s)
Amphetamines/analysis , Central Nervous System Stimulants/analysis , Neural Networks, Computer , Chromatography, Gas/methods , Reproducibility of Results , Sensitivity and Specificity , Spectroscopy, Fourier Transform Infrared/methods
11.
J Anal Toxicol ; 28(8): 655-9, 2004.
Article in English | MEDLINE | ID: mdl-15538960

ABSTRACT

A quantitative analysis was developed for the determination of cocaine, benzoylecgonine, and cocaethylene in oral fluid using liquid chromatography-tandem mass spectrometry. After internal standardization and solid-phase extraction, chromatographic separation was achieved on a reversed-phase column by gradient elution. The reconstructed mass chromatograms of the collision-induced dissociation transitions of m/z 290 --> m/z 168 (benzoylecgonine), m/z 304 --> m/z 168+119 (2'-methylbenzoylecgonine), m/z 304 --> m/z 182 (cocaine), m/z 318 --> m/z 196 (cocaethylene), and m/z 318 --> m/z 182+119 (2'-methylcocaine) were used for quantitation. The developed method was adequately validated. Good linearity was obtained from 10 to 1000 microg/L. Extraction recoveries exceeded 85% for all compounds. Excellent total and within-run reproducibilities (CV% < 20%) and accuracy figures were obtained. The limit of detection (signal-to-noise ratio >/= 3) was 1 microg/L for all three compounds. As such, a method for drug abuse confirmation analysis in oral fluid, compatible with the present day saliva collecting devices, is obtained. The method was applied to real samples (n = 15) obtained from suspected drug users, of which seven proved positive. The concentrations found in the positive samples were between 10.2 and 200.6 microg/L for cocaine, < limit of quantification (LOQ) and 10.5 microg/L for cocaethylene, and < LOQ and 59.2 microg/L for benzoylecgonine.


Subject(s)
Chromatography, Liquid/methods , Cocaine/analogs & derivatives , Cocaine/analysis , Saliva/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Substance Abuse Detection/methods , Cocaine-Related Disorders/diagnosis , Cocaine-Related Disorders/metabolism , Humans , Reproducibility of Results
12.
Anaesthesia ; 59(6): 584-9, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15144299

ABSTRACT

Two new generation carbon dioxide absorbents, DrägerSorb Free and Amsorb Plus, were studied in vitro for formation of compound A or carbon monoxide, during minimal gas flow (500 ml x min(-1)) with sevoflurane or desflurane. Compound A was assessed by gas chromatography/mass spectrometry and carbon monoxide with continuous infrared spectrometry. Fresh and dehydrated absorbents were studied. Mean (SD) time till exhaustion (inspiratory carbon dioxide concentration >or= 1 kPa) with fresh absorbents was longer with DrägerSorb Free (1233 (55) min) than with Amsorb Plus (1025 (55) min; p < 0.01). For both absorbents, values of compound A were < 1 ppm and therefore below clinically significant levels, but were up to 0.25 ppm higher with DrägerSorb Free than with Amsorb Plus. Using dehydrated absorbents, values of compound A were about 50% lower than with fresh absorbents and were identical for DrägerSorb Free and Amsorb Plus. With dehydrated absorbents, no detectable carbon monoxide was found with desflurane.


Subject(s)
Anesthesia, Closed-Circuit/methods , Carbon Dioxide/chemistry , Carbon Monoxide/chemistry , Ethers/chemistry , Hydrocarbons, Fluorinated/chemistry , Isoflurane/analogs & derivatives , Absorption , Anesthetics, Inhalation/chemistry , Calcium Chloride , Calcium Hydroxide , Desflurane , Humans , Isoflurane/chemistry , Methyl Ethers/chemistry , Sevoflurane , Temperature
14.
J Chromatogr A ; 962(1-2): 161-73, 2002 Jul 12.
Article in English | MEDLINE | ID: mdl-12198960

ABSTRACT

We present a chemometric procedure for the identification of the reference standard chromatographic peak in cases where the GC-FTIR analysis of commercial standards results in the appearance of more than one peak in the GC chromatogram. The procedure has been designed for phenethylamines, which represent the class with the largest number of individual molecules on the illicit drug market, and which are abused for their stimulant and/or hallucinogenic effects. The similarity between their vapor-phase FTIR spectra was modeled using principal component analysis (PCA), and class identity was assigned on the basis of soft independent modeling of class analogy (SIMCA). Additional peaks could be assigned to impurities in the standards, but most often they were artifacts formed during the GC-FTIR analysis of thermolabile or chemically unstable compounds. The latter case is illustrated by the identification of the reference standard chromatographic peak and FTIR spectrum of the potent psychotropic amphetamine derivative N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB), and by the elucidation of the chemical changes that occur in the molecule of MBDB due to thermal degradation.


Subject(s)
Chromatography, Gas/methods , Illicit Drugs/analysis , Spectroscopy, Fourier Transform Infrared/methods , Molecular Structure , Temperature
15.
Forensic Sci Int ; 124(1): 36-42, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11741758

ABSTRACT

A controlled study was undertaken to determine the stability of the designer drugs MDA, MDMA and MDEA in pooled serum, whole blood, water and urine samples over a period of 21 weeks. The concentrations of the individual designer drugs in the various matrices were monitored over time, in the dark at various temperatures (-20, 4 or 20 degrees C), for a low (+/- 6 ng/ml for water, serum and whole blood and +/- 150 ng/ml for urine) and a high concentration level (+/- 550 ng/ml for water, serum and whole blood and +/- 2500 ng/ml for urine). Compound concentrations were measured using a validated HPLC assay with fluorescence detection. Our study demonstrated no significant loss of the designer drugs in water and urine at any of the investigated temperatures for 21 weeks. The same results were observed in serum for up to 17 weeks, and up to 5 weeks in whole blood. After that time, the compounds could no longer be analyzed due to matrix degradation, especially in the low concentration samples that were stored at room temperature. This study demonstrates that the designer drugs, MDA, MDMA and MDEA are stable when stored at -20 degrees C for 21 weeks, even in haemolysed whole blood.


Subject(s)
3,4-Methylenedioxyamphetamine/analogs & derivatives , 3,4-Methylenedioxyamphetamine/blood , Designer Drugs , Drug Stability , Forensic Medicine , N-Methyl-3,4-methylenedioxyamphetamine/blood , 3,4-Methylenedioxyamphetamine/urine , Chromatography, High Pressure Liquid , Drug Storage , N-Methyl-3,4-methylenedioxyamphetamine/urine , Reproducibility of Results , Water
16.
Br J Anaesth ; 86(3): 345-8, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11573522

ABSTRACT

In an in vitro study, less compound A was formed when a KOH-free carbon dioxide absorbent was used. To confirm this observation we used a lung model in which carbon dioxide was fed in at 160 ml min(-1) and sampling gas was taken out for analysis at 200 ml min(-1); ventilation aimed for a PE'CO2 of 5.4 kPa. The soda lime canister temperatures in the inflow and outflow ports (Tin and Tout) were recorded. In six runs of 240 min each, a standard soda lime, Sodasorb (Grace, Epernon, France) was used and in eight runs KOH-free Sofnolime (Molecular Products, Thaxted, UK) was used. Liquid sevoflurane was injected using a syringe pump to obtain 2.1% E'. Compound A was measured by capillary gas chromatography combined with mass spectrometry. Median (range) compound Ainsp increased to a maximum of 22.7 (7.9) ppm for Sodasorb and 33.1 (20) for Sofnolime at 60 min and decreased thereafter; the difference between groups was significant (P<0.05) at each time of analysis up to 240 min. The canister temperatures were similar in both groups and increased to approximately 40 degrees C at 240 min. Contrary to expectation, compound A concentrations were greater with the KOH-free absorbent despite similar canister temperatures with both absorbents.


Subject(s)
Anesthesia, Closed-Circuit , Anesthetics, Inhalation/chemistry , Calcium Compounds/chemistry , Ethers/chemistry , Hydrocarbons, Fluorinated/chemistry , Methyl Ethers/chemistry , Oxides/chemistry , Sodium Hydroxide/chemistry , Absorption , Carbon Dioxide/chemistry , Humans , Hydroxides/chemistry , Lung , Models, Biological , Potassium Compounds/chemistry , Sevoflurane
18.
Anesthesiology ; 95(3): 750-5, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11575550

ABSTRACT

BACKGROUND: Insufficient data exist on the production of compound A during closed-system sevoflurane administration with newer carbon dioxide absorbents. METHODS: A modified PhysioFlex apparatus (Dräger, Lübeck, Germany) was connected to an artificial test lung (inflow at the top of the bellow approximately/= 160 ml/min CO2; outflow at the Y piece of the lung model approximately/= 200 ml/min, simulating oxygen consumption). Ventilation was set to obtain an end-tidal carbon dioxide partial pressure of approximately 40 mmHg. Various fresh carbon dioxide absorbents were used: Sodasorb (n = 6), Sofnolime (n = 6), and potassium hydroxide (KOH)-free Sodasorb (n = 7), Amsorb (n = 7), and lithium hydroxide (n = 7). After baseline analysis, liquid sevoflurane was injected into the circuit by syringe pump to obtain 2.1% end-tidal concentration for 240 min. At baseline and at regular intervals thereafter, end-tidal carbon dioxide partial pressure, end-tidal sevoflurane concentration, and canister inflow (T degrees(in)) and canister outflow (T degrees(out)) temperatures were measured. To measure compound Ainsp concentration in the inspired gas of the breathing circuit, 2-ml gas samples were taken and analyzed by capillary gas chromatography plus mass spectrometry. RESULTS: The median (minimum-maximum) highest compound Ainsp concentrations over the entire period were, in decreasing order: 38.3 (28.4-44.2)* (Sofnolime), 30.1 (23.9-43.7) (KOH-free Sodasorb), 23.3 (20.0-29.2) (Sodasorb), 1.6 (1.3-2.1)* (lithium hydroxide), and 1.3 (1.1-1.8)* (Amsorb) parts per million (*P < 0.01 vs. Sodasorb). After reaching their peak concentration, a decrease for Sofnolime, KOH-free Sodasorb, and Sodasorb until 240 min was found. The median (minimum-maximum) highest values for T degrees(out) were 39 (38-40), 40 (39-42), 41 (40-42), 46 (44-48)*, and 39 (38-41) degrees C (*P < 0.01 vs. Sodasorb), respectively. CONCLUSIONS: With KOH-free (but sodium hydroxide [NaOH]-containing) soda limes even higher compound A concentrations are recorded than with standard Sodasorb. Only by eliminating KOH as well as NaOH from the absorbent (Amsorb and lithium hydroxide) is no compound A produced.


Subject(s)
Anesthetics, Inhalation/metabolism , Carbon Dioxide/metabolism , Ethers/metabolism , Hydrocarbons, Fluorinated/metabolism , Methyl Ethers/metabolism , Absorption , Humans , Hydroxides , Potassium Compounds , Sevoflurane , Sodium Hydroxide , Temperature
19.
J Anal Toxicol ; 25(2): 147-51, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11300508

ABSTRACT

We present a case involving a fatality due to the combined ingestion of two different types of antidepressants. A 41-year-old Caucasian male, with a history of depression and suicide attempts, was found deceased at home. Multiple containers of medication, the MAO-inhibitor moclobemide (Aurorix), the SSRI citalopram (Cipramil), and the benzodiazepine lormetazepam (Noctamid) as active substance, as well as a bottle of whiskey were present at the scene. The autopsy findings were unremarkable, but systematic toxicological analysis (EMIT, radioimmunoassay, high-performance liquid chromatography-diode-array detection [HPLC-DAD], gas chromatography-nitrogen-phosphorus detection, and gas chromatography-mass spectrometry) revealed the following: ethanol (0.23 g/L blood, 0.67 g/L urine), lormetazepam (1.65 microg/mL urine), cotinine (0.63 microg/mL blood, 5.08 microg/mL urine), caffeine (1.20 microg/mL urine), moclobemide (and metabolites), and citalopram (and metabolite). There upon, we developed a new liquid chromatographic separation with optimized DAD, preceded by an automated solid-phase extraction, for the quantitation of the previously mentioned antidepressive drugs. The results obtained for blood and urine, respectively, were as follows: Ro 12-5637 (moclobemide N'-oxide) not detected and 424 microg/mL; Ro 12-8095 (3-keto-moclobemide) 2.26 microg/mL and 49.7 microg/mL; moclobemide 5.62 microg/mL and 204 microg/mL; desmethylcitalopram 0.42 microg/mL and 1.22 microg/mL; and citalopram 4.47 microg/mL and 19.7 microg/mL. The cause of death was attributed to the synergistic toxicity of moclobemide and citalopram, both antidepressants, which, by intentional or accidental combined ingestion, can produce a potentially lethal hyperserotoninergic state. Based on the history of the case and pharmacology of the drugs involved, the forensic pathologists ruled that the cause of death was multiple drug intoxication, resulting in a fatal "serotonin syndrome," and that the manner of death was suicide.


Subject(s)
Antidepressive Agents/poisoning , Citalopram/poisoning , Moclobemide/poisoning , Serotonin Syndrome/chemically induced , Suicide , Adult , Antidepressive Agents/metabolism , Chromatography, High Pressure Liquid , Citalopram/metabolism , Drug Combinations , Enzyme Multiplied Immunoassay Technique , Fatal Outcome , Gas Chromatography-Mass Spectrometry , Humans , Male , Moclobemide/metabolism , Radioimmunoassay , Serotonin Syndrome/pathology
20.
J Anal Toxicol ; 25(1): 45-56, 2001.
Article in English | MEDLINE | ID: mdl-11216000

ABSTRACT

An expert system applied as a screening test for amphetamine analogues found in recreational-drug exhibits (tablets or powders) is described. The knowledge base defining the reference Fourier transform infrared spectroscopic (FTIR) spectral patterns has been built according to criteria encompassing toxicological, pharmacological, and neurochemical aspects. The class identity of a compound is determined within seconds using soft independent modeling of class analogy (SIMCA). The predictive value of the system, as assessed at a testing accuracy of 95%, is expressed by a total correct classification rate of 93.93% and by a 96.30% rate of true-positive amphetamines. The specificity and the selectivity of the screening test, evaluated by testing 159 toxicologically relevant compounds, are discussed, emphasizing the chemical and physical factors affecting these parameters. Medicinal amphetamines giving cross-reactions with traditional screening techniques produce a negative result. The specificity of the system characterizes the expert system as a highly sensitive, selective, fast, and user-friendly screening test that screens for amphetamines with prediction accuracy adequate for investigations in analytical toxicology.


Subject(s)
Amphetamines/analysis , Hallucinogens/analysis , Chromatography, Gas , Spectroscopy, Fourier Transform Infrared
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