The Experts below are selected from a list of 165 Experts worldwide ranked by ideXlab platform
D. Enk - One of the best experts on this subject based on the ideXlab platform.
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ventrain an ejector ventilator for emergency use
BJA: British Journal of Anaesthesia, 2012Co-Authors: A Hamaekers, P. A. J. Borg, D. EnkAbstract:Background A small, flow-regulated, manually operated ventilator designed for ventilation through a narrow-bore Transtracheal Catheter (TTC) has become available (Ventrain, Dolphys Medical BV, Eindhoven, The Netherlands). It is driven by a predetermined flow of oxygen from a high-pressure source and facilitates expiration by suction. The aim of this bench study was to test the efficacy of this new ventilator. Methods The driving pressure, generated insufflation, and suction pressures and also the suction capacity of the Ventrain were measured at different oxygen flows. The minute volume achieved in an artificial lung through a TTC with an inner diameter (ID) of 2 mm was determined at different settings. Results Oxygen flows of 6–15 litre min−1 resulted in driving pressures of 0.5–2.3 bar. Insufflation pressures, measured proximal to the TTC, ranged from 23 to 138 cm H2O. The maximal subatmospheric pressure build-up was −217 cm H2O. The suction capacity increased to a maximum of 12.4 litre min−1 at an oxygen flow of 15 litre min−1. At this flow, the achievable minute volume through the TTC ranged from 5.9 to 7.1 litres depending on the compliance of the artificial lung. Conclusions The results of this bench study suggest that the Ventrain is capable of achieving a normal minute volume for an average adult through a 2 mm ID TTC. Further in vivo studies are needed to determine the value of the Ventrain as a portable emergency ventilator in a ‘cannot intubate, cannot ventilate’ situation.
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Ventilation through a small-bore Catheter: optimizing expiratory ventilation assistance
British journal of anaesthesia, 2010Co-Authors: A. E. W. Hamaekers, T. Götz, P. A. J. Borg, D. EnkAbstract:Abstract Background Emergency ventilation through a small-bore Transtracheal Catheter can be lifesaving in a ‘cannot intubate, cannot ventilate' situation. Ejectors, capable of creating suction by the Bernoulli principle, have been proposed to facilitate expiration through small-bore Catheters. In this bench study, we compared a novel, purpose-built ventilation ejector (DE 5) with a previously proposed, modified industrial ejector (SBP 07). Methods The generated insufflation pressures, suction pressures in static and dynamic situations, and also suction capacities and entrainment ratios of the SBP 07 and the DE 5 were determined. The DE 5 was also tested in a lung simulator with a simulated complete upper airway obstruction. Inspiratory and expiratory times through a Transtracheal Catheter were measured at various flow rates and achievable minute volumes were calculated. Results In a static situation, the SBP 07 showed a more negative pressure build-up compared with the DE 5. However, in a dynamic situation, the DE 5 generated a more negative pressure, resulting in a higher suction capacity. Employment of the DE 5 at a flow rate of 18 litre min−1 allowed a minute volume through the Transtracheal Catheter of up to 8.27 litre min−1 at a compliance of 100 ml cm H2O−1. The efficiency of the DE 5 depended on the flow rate of the driving gas and the compliance of the lung simulator. Conclusion In laboratory tests, the DE 5 is an optimized ventilation ejector suitable for applying expiratory ventilation assistance. Further research may confirm the clinical applicability as a portable emergency ventilator for use with small-bore Catheters.
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Achieving an adequate minute volume through a 2 mm Transtracheal Catheter in simulated upper airway obstruction using a modified industrial ejector
British journal of anaesthesia, 2010Co-Authors: A. E. W. Hamaekers, T. Götz, P. A. J. Borg, D. EnkAbstract:Background Needle cricothyrotomy and subsequent Transtracheal jet ventilation (TTJV) is one of the last options to restore oxygenation while managing an airway emergency. However, in cases of complete upper airway obstruction, conventional TTJV is ineffective and dangerous. We transformed a small, industrial ejector into a simple, manual ventilator providing expiratory ventilation assistance (EVA). Methods An ejector pump was modified to allow both insufflation of oxygen and jet-assisted expiration through an attached 75 mm long Transtracheal Catheter (TTC) with an inner diameter (ID) of 2 mm by alternately occluding and releasing the gas outlet of the ejector pump. In a lung simulator, the modified ejector pump was tested at different compliances and resistances. Inspiration and expiration times were measured and achievable minute volumes (MVs) were calculated to determine the effect of EVA. Results The modified ejector pump shortened the expiration time and an MV up to 6.6 litre min−1 could be achieved through a 2 mm ID TTC in a simulated obstructed airway. Conclusions The principle of ejector-based EVA seems promising and deserves further evaluation.
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a bench study of ventilation via two self assembled jet devices and the oxygen flow modulator in simulated upper airway obstruction
Anaesthesia, 2009Co-Authors: A Hamaekers, P. A. J. Borg, D. EnkAbstract:Summary In managing an obstructed upper airway, an emergency Transtracheal ventilation device needs to function as a bidirectional airway, allowing both insufflation of oxygen and egress of gas. The aim of the present study was to determine the capability of two self-assembled, three-way stopcock based jet devices and the Oxygen Flow Modulator to function as a bidirectional airway in conjunction with a small lumen Catheter. For each device the effective pressures at the Catheter’s tip during the expiratory phase and the achievable minute volumes were determined in a laboratory set-up. Using the three-way stopcock based jet devices, changing the connection position of the Transtracheal Catheter from the in-line port to the side port of the three-way stopcock resulted in a decrease of expiratory pressure at the Catheter’s tip from a dangerous mean (SD) of 71.1 (0.08) cmH2O to −14.71 (0.05) cmH2O. Yet this negative expiratory pressure did not facilitate the egress of gas. All devices tested impeded the expiratory outflow and hence decreased the achievable minute volume. This decrease in minute volume was smallest with the Oxygen Flow Modulator.
Hans J. Gerig - One of the best experts on this subject based on the ideXlab platform.
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A severe complication after laser-induced damage to a Transtracheal Catheter during endoscopic laryngeal microsurgery.
Anesthesia and analgesia, 2004Co-Authors: Bettina Leemann, Rudolf Grossenbacher, Thomas Heidegger, Thomas W. Schnider, Hans J. GerigAbstract:Subcutaneous emphysema and pneumothorax is a rare and severe complication of percutaneous Transtracheal jet ventilation, usually caused by obstruction of the upper airway or displacement of the tracheal Catheter. Nevertheless, it is our preferred technique for endoscopic laryngeal laser surgery. We
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Fiberoptically-guided insertion of Transtracheal Catheters.
Anesthesia and analgesia, 2001Co-Authors: Hans J. Gerig, Thomas Heidegger, Brigitte Ulrich, Rudolf Grossenbacher, Georg KreienbuehlAbstract:IMPLICATIONS Regular use of the Transtracheal Catheter (TTC) both offers an opportunity for training for the difficult airway and facilitates elective endoscopic surgery. Fiberoptic guidance and exploratory puncture improve the insertion of the TTC.
P. A. J. Borg - One of the best experts on this subject based on the ideXlab platform.
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ventrain an ejector ventilator for emergency use
BJA: British Journal of Anaesthesia, 2012Co-Authors: A Hamaekers, P. A. J. Borg, D. EnkAbstract:Background A small, flow-regulated, manually operated ventilator designed for ventilation through a narrow-bore Transtracheal Catheter (TTC) has become available (Ventrain, Dolphys Medical BV, Eindhoven, The Netherlands). It is driven by a predetermined flow of oxygen from a high-pressure source and facilitates expiration by suction. The aim of this bench study was to test the efficacy of this new ventilator. Methods The driving pressure, generated insufflation, and suction pressures and also the suction capacity of the Ventrain were measured at different oxygen flows. The minute volume achieved in an artificial lung through a TTC with an inner diameter (ID) of 2 mm was determined at different settings. Results Oxygen flows of 6–15 litre min−1 resulted in driving pressures of 0.5–2.3 bar. Insufflation pressures, measured proximal to the TTC, ranged from 23 to 138 cm H2O. The maximal subatmospheric pressure build-up was −217 cm H2O. The suction capacity increased to a maximum of 12.4 litre min−1 at an oxygen flow of 15 litre min−1. At this flow, the achievable minute volume through the TTC ranged from 5.9 to 7.1 litres depending on the compliance of the artificial lung. Conclusions The results of this bench study suggest that the Ventrain is capable of achieving a normal minute volume for an average adult through a 2 mm ID TTC. Further in vivo studies are needed to determine the value of the Ventrain as a portable emergency ventilator in a ‘cannot intubate, cannot ventilate’ situation.
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Ventilation through a small-bore Catheter: optimizing expiratory ventilation assistance
British journal of anaesthesia, 2010Co-Authors: A. E. W. Hamaekers, T. Götz, P. A. J. Borg, D. EnkAbstract:Abstract Background Emergency ventilation through a small-bore Transtracheal Catheter can be lifesaving in a ‘cannot intubate, cannot ventilate' situation. Ejectors, capable of creating suction by the Bernoulli principle, have been proposed to facilitate expiration through small-bore Catheters. In this bench study, we compared a novel, purpose-built ventilation ejector (DE 5) with a previously proposed, modified industrial ejector (SBP 07). Methods The generated insufflation pressures, suction pressures in static and dynamic situations, and also suction capacities and entrainment ratios of the SBP 07 and the DE 5 were determined. The DE 5 was also tested in a lung simulator with a simulated complete upper airway obstruction. Inspiratory and expiratory times through a Transtracheal Catheter were measured at various flow rates and achievable minute volumes were calculated. Results In a static situation, the SBP 07 showed a more negative pressure build-up compared with the DE 5. However, in a dynamic situation, the DE 5 generated a more negative pressure, resulting in a higher suction capacity. Employment of the DE 5 at a flow rate of 18 litre min−1 allowed a minute volume through the Transtracheal Catheter of up to 8.27 litre min−1 at a compliance of 100 ml cm H2O−1. The efficiency of the DE 5 depended on the flow rate of the driving gas and the compliance of the lung simulator. Conclusion In laboratory tests, the DE 5 is an optimized ventilation ejector suitable for applying expiratory ventilation assistance. Further research may confirm the clinical applicability as a portable emergency ventilator for use with small-bore Catheters.
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Achieving an adequate minute volume through a 2 mm Transtracheal Catheter in simulated upper airway obstruction using a modified industrial ejector
British journal of anaesthesia, 2010Co-Authors: A. E. W. Hamaekers, T. Götz, P. A. J. Borg, D. EnkAbstract:Background Needle cricothyrotomy and subsequent Transtracheal jet ventilation (TTJV) is one of the last options to restore oxygenation while managing an airway emergency. However, in cases of complete upper airway obstruction, conventional TTJV is ineffective and dangerous. We transformed a small, industrial ejector into a simple, manual ventilator providing expiratory ventilation assistance (EVA). Methods An ejector pump was modified to allow both insufflation of oxygen and jet-assisted expiration through an attached 75 mm long Transtracheal Catheter (TTC) with an inner diameter (ID) of 2 mm by alternately occluding and releasing the gas outlet of the ejector pump. In a lung simulator, the modified ejector pump was tested at different compliances and resistances. Inspiration and expiration times were measured and achievable minute volumes (MVs) were calculated to determine the effect of EVA. Results The modified ejector pump shortened the expiration time and an MV up to 6.6 litre min−1 could be achieved through a 2 mm ID TTC in a simulated obstructed airway. Conclusions The principle of ejector-based EVA seems promising and deserves further evaluation.
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a bench study of ventilation via two self assembled jet devices and the oxygen flow modulator in simulated upper airway obstruction
Anaesthesia, 2009Co-Authors: A Hamaekers, P. A. J. Borg, D. EnkAbstract:Summary In managing an obstructed upper airway, an emergency Transtracheal ventilation device needs to function as a bidirectional airway, allowing both insufflation of oxygen and egress of gas. The aim of the present study was to determine the capability of two self-assembled, three-way stopcock based jet devices and the Oxygen Flow Modulator to function as a bidirectional airway in conjunction with a small lumen Catheter. For each device the effective pressures at the Catheter’s tip during the expiratory phase and the achievable minute volumes were determined in a laboratory set-up. Using the three-way stopcock based jet devices, changing the connection position of the Transtracheal Catheter from the in-line port to the side port of the three-way stopcock resulted in a decrease of expiratory pressure at the Catheter’s tip from a dangerous mean (SD) of 71.1 (0.08) cmH2O to −14.71 (0.05) cmH2O. Yet this negative expiratory pressure did not facilitate the egress of gas. All devices tested impeded the expiratory outflow and hence decreased the achievable minute volume. This decrease in minute volume was smallest with the Oxygen Flow Modulator.
A Patessio - One of the best experts on this subject based on the ideXlab platform.
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Can long-term oxygen therapy improve exercise capacity and prognosis?
Respiration; international review of thoracic diseases, 1992Co-Authors: C F Donner, A Braghiroli, A PatessioAbstract:The lack of studies as to whether the correction of desaturations during exercise can play a role in improving survival still leaves many problems usually met in the common practice open. (1) Why prescribe long-term oxygen therapy (LTOT) on exercise? Up to now, supplemental oxygen during exercise seems more an approach to the 'dyspnea symptom' than a pivotal component of a comprehensive strategy for long-term management of severe chronic airway obstruction. (2) Who needs LTOT on exercise? It seems reasonable to correct desaturations if this leads to a substantial improvement in exercise tolerance. As to the method of clinical assessment, pulse oximetry can be used for measuring desaturation between rest and exercise, although absolute values are not reliable. (3) How to prescribe LTOT on exercise? In practice, the O2 flow able to prevent desaturation on exercise, restoring an SaO2 greater than 90%, is the usual prescription criterion after an appropriate testing able to demonstrate a significant increase in exercise tolerance and conducted comparing the results breathing air with those on O2, the patient being unaware of the inhaled mixture. (4) How to administrate LTOT on exercise? A portable source is usually employed to allow the greatest possible independency. A reservoir nasal cannula can halve the oxygen wastage and is less expensive than a pulse demand valve. In patients needing 24-hour oxygen therapy the Transtracheal Catheter is being used more and more at present.(ABSTRACT TRUNCATED AT 250 WORDS)
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Can long-term oxygen therapy improve exercise capacity and prognosis ?
Respiration, 1992Co-Authors: C F Donner, A Braghiroli, A PatessioAbstract:The lack of studies as to whether the correction of desaturations during exercise can play a role in improving survival still leaves many problems usually met in the common practice open. (1) Why prescribe long-term oxygen therapy (LTOT) on exercise? Up to now, supplemental oxygen during exercise seems more an approach to the ‘dyspnea symptom’ than a pivotal component of a comprehensive strategy for long-term management of severe chronic airway obstruction. (2) Who needs LTOT on exercise? It seems reasonable to correct desaturations if this leads to a substantial improvement in exercise tolerance. As to the method of clinical assessment, pulse oximetry can be used for measuring desaturation between rest and exercise, although absolute values are not reliable. (3) How to prescribe LTOT on exercise? In practice, the O2 flow able to prevent desaturation on exercise, restoring an SaO2 > 90%, is the usual prescription criterion after an appropriate testing able to demonstrate a significant increase in exercise tolerance and conducted comparing the results breathing air with those on O2, the patient being unaware of the inhaled mixture. (4) How to administrate LTOT on exercise? A portable source is usually employed to allow the greatest possible independency. A reservoir nasal cannula can halve the oxygen wastage and is less expensive than a pulse demand valve. In patients needing 24-hour oxygen therapy the Transtracheal Catheter is being used more and more at present. We need controlled studies on the long-term effects of oxygen on exercise, whereas retrospective studies on survival in patients with exercise desaturations can give short-term contributions to a better comprehension of this subject.
P Ravussin - One of the best experts on this subject based on the ideXlab platform.
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Transtracheal high frequency jet ventilation for endoscopic airway surgery a multicentre study
BJA: British Journal of Anaesthesia, 2001Co-Authors: J L Bourgain, Eric Desruennes, M Fischler, P RavussinAbstract:Serious complications during high frequency jet ventilation (HFJV) are rare and have been documented in animals and in case reports or short series of patients with a difficult airway. We report complications of Transtracheal HFFJV in a prospective multicentre study of 643 patients having laryngoscopy or laryngeal laser surgery. A Transtracheal Catheter could not be inserted in two patients (0.3%). Subcutaneous emphysema (8.4%) was more frequent after multiple tracheal punctures. There were seven pneumothoraces (1%), two after laser damage to the injector, one after difficult laryngoscopy, four with no clear cause. Arterial desaturation of oxygen was more frequent during laser surgery and in overweight patients. Transtracheal ventilation from a ventilator with an automatic cut-off device is a reliable method for experienced users. Control of airway pressure does not prevent a low frequency of pneumothorax.
