The Experts below are selected from a list of 129 Experts worldwide ranked by ideXlab platform
Jolyon P Mitchell - One of the best experts on this subject based on the ideXlab platform.
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internal volumes of pharmaceutical compendial induction port next generation impactor with and without its pre separator and several configurations of the andersen cascade impactor with and without pre separator
Journal of Aerosol Medicine and Pulmonary Drug Delivery, 2020Co-Authors: Daryl L. Roberts, Frank Chambers, Mark Copley, Jolyon P MitchellAbstract:Background: Determination of aerosol aerodynamic particle size distributions (APSD) from dry-powder inhalers (DPIs), following quality control procedures in the pharmacopeial compendia, requires that the Flow through the measurement apparatus, comprising induction port, optional pre-separator, and cascade impactor, starts from zero on actuation of the inhaler, using a solenoid valve to apply vacuum to the apparatus exit. The Target Flow Rate, governed by the inhaler resistance, is reached some time afterward. Understanding the behavior of the DPI design-specific Flow Rate-rise time curve can provide information about the kinetics of the initial powder dispersion in the inhaler and subsequent transport through the APSD measurement equipment. AccuRate and precise measures of the internal volume of each component of this apparatus are required to enable reliable relationships to be established between this parameter and those defining the Flow Rate-rise time curve. Methods: An improved method is described that involves progressive withdrawal of an accuRately known volume of air from the interior passageways of the apparatus-on-test that are closed to the outside atmosphere. This approach is applicable for determining internal volumes of components having complex internal geometries. Filling some components with water, along with volumetric or gravimetric measurement, has proven valuable for the induction port and for checking other measurements. Results: Values of internal volume are provided for the USP (United States Pharmacopeia)/PhEur (European Pharmacopoeia) induction port, the Next-Generation Impactor (NGI™) with and without its pre-separator, and various Andersen 8-stage cascade impactor configurations with and without their pre-separators. Conclusion: These data are more accuRate and precise, and therefore update those reported by Copley et al.
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determination of passive dry powder inhaler aerodynamic particle size distribution by multi stage cascade impactor international pharmaceutical aerosol consortium on regulation science ipac rs recommendations to support both product quality control a
Aaps Pharmscitech, 2019Co-Authors: Jolyon P Mitchell, Stephen W Stein, William H Doub, Adrian P Goodey, David J Christopher, Rajni B Patel, Terrence P Tougas, Svetlana LyapustinaAbstract:The multi-stage cascade impactor (CI) is the mainstay method for the determination of the aerodynamic particle size distribution (APSD) of aerosols emitted from orally inhaled products (OIPs). CIs are designed to opeRate at a constant Flow Rate throughout the measurement process. However, it is necessary to mimic an inhalation maneuver to disperse the powder into an aerosol when testing passive dry powder inhalers (DPIs), which constitute a significant portion of available products in this inhaler class. Methods in the pharmacopeial compendia intended for product quality assurance initiate sampling by applying a vacuum to the measurement apparatus using a timer-opeRated solenoid valve located downstream of the CI, resulting in a period when the Flow Rate through the impactor rapidly increases from zero towards the Target Flow Rate. This article provides recommendations for achieving consistent APSD measurements, including selection of the CI, pre-separator, and Flow control equipment, as well as reviewing considerations that relate to the shape of the Flow Rate-sampling time profile. Evidence from comparisons of different DPIs delivering the same active pharmaceutical ingredients (APIs) is indicative that the compendial method for APSD measurement is insensitive as a predictor of pharmacokinetic outcomes. Although inappropriate for product quality testing, guidance is therefore provided towards adopting a more clinically realistic methodology, including the use of an anatomically appropriate inlet and mimicking patient inhalation at the DPI while operating the CI at constant Flow Rate. Many of these recommendations are applicable to the testing of other OIP classes.
Nandor Marczin - One of the best experts on this subject based on the ideXlab platform.
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early outcomes of bilateral sequential single lung transplantation after ex vivo lung evaluation and reconditioning
Journal of Heart and Lung Transplantation, 2011Co-Authors: B Zych, Aron Frederik Popov, George Stavri, Alison Bashford, Toufan Bahrami, Mohamed Amrani, Fabio De Robertis, M Carby, Nandor MarczinAbstract:Background Ex vivo lung perfusion (EVLP) is a novel approach for extended evaluation and/or reconditioning of donor lungs not meeting standard International Society for Heart and Lung Transplantation criteria for transplantation. Methods We retrospectively evaluated 13 consecutive EVLP runs between January 2009 and December 2010. Lungs rejected for routine transplantation were implanted to the EVLP circuit and reperfused using acellular supplemented Steen Solution (Vitrolife, Goteborg, Sweden) up to a Target Flow Rate of 40% of the donor's calculated Flow at a cardiac index of 3.0 liters/min/m 2 ; Target left atrial pressure 2 O. Hemodynamic and respiratory data monitoring with hourly clinical assessment were performed. Donor data, conversion Rate to transplantation, and recipient outcome were analyzed. Results Donor data ( n = 13) were: age, 44.23 ± 8.33 years; female/male, 8:5; cause of death: intracranial hemorrhage, 11 (85%), stroke, 1 (7.5%), hypoxic brain injury, 1 (7.5%); smoking history, 9 (69%), 17.44 ± 8.92 pack-years; mechanical ventilation, 102.6 ± 91.92 hours; chest x-ray imaging: abnormal, 12 (92.5%); normal, 1 (7.5%). EVLP: mean 141 ± 28.83 minutes. Arterial partial pressure of oxygen/fraction of inspired oxygen 100% before termination of the circuit vs pre-retrieval value: 57.32 ± 9.1 vs 42.36 ± 14.13 kPa ( p Conclusions EVLP may facilitate assessment and/or reconditioning of borderline lungs, with a conversion Rate of 46 % and good short-term survival.
Daryl L. Roberts - One of the best experts on this subject based on the ideXlab platform.
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internal volumes of pharmaceutical compendial induction port next generation impactor with and without its pre separator and several configurations of the andersen cascade impactor with and without pre separator
Journal of Aerosol Medicine and Pulmonary Drug Delivery, 2020Co-Authors: Daryl L. Roberts, Frank Chambers, Mark Copley, Jolyon P MitchellAbstract:Background: Determination of aerosol aerodynamic particle size distributions (APSD) from dry-powder inhalers (DPIs), following quality control procedures in the pharmacopeial compendia, requires that the Flow through the measurement apparatus, comprising induction port, optional pre-separator, and cascade impactor, starts from zero on actuation of the inhaler, using a solenoid valve to apply vacuum to the apparatus exit. The Target Flow Rate, governed by the inhaler resistance, is reached some time afterward. Understanding the behavior of the DPI design-specific Flow Rate-rise time curve can provide information about the kinetics of the initial powder dispersion in the inhaler and subsequent transport through the APSD measurement equipment. AccuRate and precise measures of the internal volume of each component of this apparatus are required to enable reliable relationships to be established between this parameter and those defining the Flow Rate-rise time curve. Methods: An improved method is described that involves progressive withdrawal of an accuRately known volume of air from the interior passageways of the apparatus-on-test that are closed to the outside atmosphere. This approach is applicable for determining internal volumes of components having complex internal geometries. Filling some components with water, along with volumetric or gravimetric measurement, has proven valuable for the induction port and for checking other measurements. Results: Values of internal volume are provided for the USP (United States Pharmacopeia)/PhEur (European Pharmacopoeia) induction port, the Next-Generation Impactor (NGI™) with and without its pre-separator, and various Andersen 8-stage cascade impactor configurations with and without their pre-separators. Conclusion: These data are more accuRate and precise, and therefore update those reported by Copley et al.
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A European Pharmaceutical Aerosol Group (EPAG)-led cross-industry assessment of inlet Flow Rate profiles of compendial DPI test systems: Part 1 – experimental data
2018Co-Authors: J.p. Mitchell, R Greguletz, C.g. Blatchford, Daryl L. Roberts, Hendrik VersteegAbstract:We report outcomes from an EPAG-led cross-industry study, characterizing Flow Rate/elapsed-time profiles of equipment used for testing dry powder inhalers (DPIs). A thermal mass Flow sensor was used by nine organizations in a round-robin approach to record inlet Flow Rate-time profiles of individual participant compendial test systems (TS) including either sample collection tubes (SCT) or a cascade impactor (either the Andersen 8-stage non-viable impactor, ACI, or the Next Generation Impactor, NGI) equipped with USP/PhEur induction port and pre-separator. An inlet orifice geneRated a 4-kPa pressure drop at each of the Target Flow Rates (30, 60 and 90 L/min), simulating a pressure drop typical for high-, medium- and low-resistance DPIs respectively. Rise times to 90% of these Target Flow Rates (t90) were longest with largest internal dead volume and followed the order NGI>ACI >SCT>TS. When the surrogate DPI (4-kPa orifice) was absent, t90 values generally lengthened with increasing Target Flow Rate. In contrast, the opposite behaviour was observed when the surrogate DPI was present. A Flow acceleration parameter was also calculated, expressed as the slope between the 20% and 80% Flow Rates of each final steady Flow value (slopet20/t80). Greater Flow acceleration occurred at higher final Flow Rates, irrespective of apparatus, but the presence of the surrogate DPI was associated with slower Flow acceleration. These Flow Rate-rise time profiles will be useful for those involved in evaluating equipment for characterizing both existing and new DPIs
Yuichi Shinkoda - One of the best experts on this subject based on the ideXlab platform.
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Velocity‐based Target Flow Rate for high‐Flow nasal cannula oxygen therapy
Pediatrics international : official journal of the Japan Pediatric Society, 2020Co-Authors: Ryo Kusubae, Masako Hirabayashi, Naho Nakazaki, Yuichi ShinkodaAbstract:Background To retrospectively assess whether the average inspiratory Flow velocity-based initial Flow Rate in high-Flow nasal cannula (HFNC) therapy could be well toleRated and safely used for infants and children hospitalized with modeRate to severe respiratory failure. Methods Thirty-three patients without underlying diseases (22 males; 67%), hospitalized to receive HFNC therapy for infection-related respiratory failure, were analyzed. The median age was 2 months (interquartile range, 1 month to 1 year). Patients with dyspnea and carbon dioxide partial pressure (pCO2 ) >50 mmHg or venous blood pH Results One patient could not toleRate the cannula. Of the remaining 32 patients, 81% (n=26) had an actual initial Flow Rate within 1 L of the Target Flow Rate; these patients were evaluated for changes in fraction of inspired oxygen (FiO2 ), pH, and pCO2 values after 24 hours. Three patients required higher FiO2 , one showed a persistent pH 50 mmHg. No patient required non-invasive positive-pressure ventilation, and one required intubation. Pneumothorax was not reported in any patient. Conclusions The average inspiratory Flow velocity-based initial Flow Rate was well-toleRated without sedation, and there were no severe complications. Starting at this Flow Rate would improve the use of HFNC therapy in the pediatric ward, possibly reducing the need for more invasive modes of ventilation.
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velocity based Target Flow Rate for high Flow nasal cannula oxygen therapy
Pediatrics International, 2020Co-Authors: Ryo Kusubae, Masako Hirabayashi, Naho Nakazaki, Yuichi ShinkodaAbstract:Background To retrospectively assess whether the average inspiratory Flow velocity-based initial Flow Rate in high-Flow nasal cannula (HFNC) therapy could be well toleRated and safely used for infants and children hospitalized with modeRate to severe respiratory failure. Methods Thirty-three patients without underlying diseases (22 males; 67%), hospitalized to receive HFNC therapy for infection-related respiratory failure, were analyzed. The median age was 2 months (interquartile range, 1 month to 1 year). Patients with dyspnea and carbon dioxide partial pressure (pCO2 ) >50 mmHg or venous blood pH Results One patient could not toleRate the cannula. Of the remaining 32 patients, 81% (n=26) had an actual initial Flow Rate within 1 L of the Target Flow Rate; these patients were evaluated for changes in fraction of inspired oxygen (FiO2 ), pH, and pCO2 values after 24 hours. Three patients required higher FiO2 , one showed a persistent pH 50 mmHg. No patient required non-invasive positive-pressure ventilation, and one required intubation. Pneumothorax was not reported in any patient. Conclusions The average inspiratory Flow velocity-based initial Flow Rate was well-toleRated without sedation, and there were no severe complications. Starting at this Flow Rate would improve the use of HFNC therapy in the pediatric ward, possibly reducing the need for more invasive modes of ventilation.
Ryo Kusubae - One of the best experts on this subject based on the ideXlab platform.
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Velocity‐based Target Flow Rate for high‐Flow nasal cannula oxygen therapy
Pediatrics international : official journal of the Japan Pediatric Society, 2020Co-Authors: Ryo Kusubae, Masako Hirabayashi, Naho Nakazaki, Yuichi ShinkodaAbstract:Background To retrospectively assess whether the average inspiratory Flow velocity-based initial Flow Rate in high-Flow nasal cannula (HFNC) therapy could be well toleRated and safely used for infants and children hospitalized with modeRate to severe respiratory failure. Methods Thirty-three patients without underlying diseases (22 males; 67%), hospitalized to receive HFNC therapy for infection-related respiratory failure, were analyzed. The median age was 2 months (interquartile range, 1 month to 1 year). Patients with dyspnea and carbon dioxide partial pressure (pCO2 ) >50 mmHg or venous blood pH Results One patient could not toleRate the cannula. Of the remaining 32 patients, 81% (n=26) had an actual initial Flow Rate within 1 L of the Target Flow Rate; these patients were evaluated for changes in fraction of inspired oxygen (FiO2 ), pH, and pCO2 values after 24 hours. Three patients required higher FiO2 , one showed a persistent pH 50 mmHg. No patient required non-invasive positive-pressure ventilation, and one required intubation. Pneumothorax was not reported in any patient. Conclusions The average inspiratory Flow velocity-based initial Flow Rate was well-toleRated without sedation, and there were no severe complications. Starting at this Flow Rate would improve the use of HFNC therapy in the pediatric ward, possibly reducing the need for more invasive modes of ventilation.
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velocity based Target Flow Rate for high Flow nasal cannula oxygen therapy
Pediatrics International, 2020Co-Authors: Ryo Kusubae, Masako Hirabayashi, Naho Nakazaki, Yuichi ShinkodaAbstract:Background To retrospectively assess whether the average inspiratory Flow velocity-based initial Flow Rate in high-Flow nasal cannula (HFNC) therapy could be well toleRated and safely used for infants and children hospitalized with modeRate to severe respiratory failure. Methods Thirty-three patients without underlying diseases (22 males; 67%), hospitalized to receive HFNC therapy for infection-related respiratory failure, were analyzed. The median age was 2 months (interquartile range, 1 month to 1 year). Patients with dyspnea and carbon dioxide partial pressure (pCO2 ) >50 mmHg or venous blood pH Results One patient could not toleRate the cannula. Of the remaining 32 patients, 81% (n=26) had an actual initial Flow Rate within 1 L of the Target Flow Rate; these patients were evaluated for changes in fraction of inspired oxygen (FiO2 ), pH, and pCO2 values after 24 hours. Three patients required higher FiO2 , one showed a persistent pH 50 mmHg. No patient required non-invasive positive-pressure ventilation, and one required intubation. Pneumothorax was not reported in any patient. Conclusions The average inspiratory Flow velocity-based initial Flow Rate was well-toleRated without sedation, and there were no severe complications. Starting at this Flow Rate would improve the use of HFNC therapy in the pediatric ward, possibly reducing the need for more invasive modes of ventilation.