Дисертації з теми "High Frequency Percussive Ventilation"
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Riscica, Fabio. "Online characterization of high - frequency percussive ventilator." Doctoral thesis, Università degli studi di Trieste, 2011. http://hdl.handle.net/10077/4654.
Повний текст джерелаThe thesis describes the study on the characterization of the percussive ventilator; the activities have been carried out in cooperation with the “D.A.I. di Medicina Perioperatoria, Terapia Intensiva ed Emergenza - UCO di Anestesia, Rianimazione e Terapia Antalgica dell'Azienda Mista Universitaria - Ospedaliera di Trieste”. The first chapter describes the physiology of the respiratory system and the classical models presented in literature, the second chapter illustrates the main modes of mechanical ventilation, particularly in the percussive ventilation. The third chapter describes the classical laboratory equipment for the measurement of breathing. The fourth chapter examines the state of the art of methods and instruments for the analysis of respiratory parameters. The fifth chapter discusses the instruments for measuring respiratory parameters, developed in the biomedical laboratory of the DEEI of University of Trieste. The sixth chapter contains a detailed study on the characterization of the percussive ventilator: the model, the method for estimating parameters, the system tests and the results. Particularly, the ability to monitor respiratory parameters by using the instrument developed avoids the volutrauma (alveolar-capillary permeability increase owing to excessive distension of the lung) during controlled ventilation. The instrument also allows to accurately estimate the lung elastance, determining factor of the volume distribution in the used model. At the conclusion of the work, the seventh chapter summarizes the results from the study of the volumes distribution in the two-compartment model of the lung conditioned to percussive ventilation.
XXIII Ciclo
1965
Ajčević, Miloš. "Personalized setup of high frequency percussive ventilator by estimation of respiratory system viscoelastic parameters." Doctoral thesis, Università degli studi di Trieste, 2015. http://hdl.handle.net/10077/10976.
Повний текст джерелаHigh Frequency Percussive Ventilation (HFPV) is a non-conventional ventilatory modality which has proven highly effective in patients with severe gas exchange impairment. However, at the present time, HFPV ventilator provides only airway pressure measurement. The airway pressure measurements and gas exchange analysis are currently the only parameters that guide the physician during the HFPV ventilator setup and treatment monitoring. The evaluation of respiratory system resistance and compliance parameters in patients undergoing mechanical ventilation is used for lung dysfunctions detection, ventilation setup and treatment effect evaluation. Furthermore, the pressure measured by ventilator represents the sum of the endotracheal tube pressure drop and the tracheal pressure. From the clinical point of view, it is very important to take into account the real amount of pressure dissipated by endotracheal tube to avoid lung injury. HFPV is pressure controlled logic ventilation, thus hypoventilation and hyperventilation cases are possible because of tidal volume variations in function of pulmonary and endotracheal tube impedance. This thesis offers a new approach for HFPV ventilator setup in accordance with protective ventilatory strategy and optimization of alveolar recruitment using estimation of the respiratory mechanics parameters and endotracheal pressure drop. Respiratory system resistance and compliance parameters were estimated, firstly in vitro and successively in patients undergoing HFPV, applying least squares regression on Dorkin high frequency model starting from measured respiratory signals. The Blasius model was identified as the most adequate to estimate pressure drop across the endotracheal tube during HFPV. Beside measurement device was developed in order to measure respiratory parameters in patients undergoing HFPV. The possibility to tailor HFPV ventilator setup, using respiratory signals measurement and estimation of respiratory system resistance, compliance and endotracheal tube pressure drop, provided by this thesis, opens a new prospective to this particular ventilatory strategy, improving its beneficial effects and minimizing ventilator-induced lung damage.
XXVII Ciclo
1981
Lucangelo, Umberto. "Titration of High Frequency Percussive Ventilation by means of real-time monitoring of the viscoelastic respiratory system properties and endotracheal tubes pressure drop." Doctoral thesis, Università degli studi di Trieste, 2014. http://hdl.handle.net/10077/9992.
Повний текст джерелаThe use of High Frequency Percussive Ventilation (HFPV) is still debated although this type of non-conventional ventilation has proven effective and safe in patients with acute respiratory failure. In the clinical practice, HFPV is not an intuitive ventilatory modality and the absence of real-time delivered volume monitoring produces disaffection among the physicians. Avoiding the "volutrauma" is the cornerstone of the "protective ventilation strategy", which assumes a constant monitoring of inspiratory volume delivered to the patient. Currently the system capable of delivering HFPV is the VDR-4® (Volumetric Diffusive Respirator), which provides only analog airway pressure waveform and digital output of peak and the mean airway pressure. The latter is involved in the determination of oxygenation and hemodynamics, irrespective of the mode of ventilation. At the present time, the mean airway pressure, together with gas exchange analysis, are the only parameters that indirectly guide the physician in assessing the clinical effectiveness of HFPV. Till now, flow, volume and pressure curves generated by HFPV have never been studied in relation to the specific patients respiratory mechanics. The real-time examination of these parameters could allow the physicians to analyze and understand elements of respiratory system mechanics as compliance (Crs), resistance (Rrs), inertance (Irs) and of patient-ventilator interaction. The mechanical effects are complex and result from interactions between ventilator settings and patient’s respiratory system impedance. The aim of this doctoral thesis was to acquire and study volume and respiratory parameters during HFPV in order to explain this complex patients-machine interaction and transfer the results in clinical practice.
XXVI Ciclo
1959
Varekojis, Sarah Meredith. "A Comparison of the Therapeutic Effectiveness and Acceptance of Conventional Postural Drainage and Percussion, Intrapulmonary Percussive Ventilation and High Frequency Chest Wall Compression in Hospitalized Patients with Cystic Fibrosis." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1420644684.
Повний текст джерелаAjibose, Olusegun K. "Nonlinear dynamics and contact fracture mechanics of high frequency percussive drilling." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=61011.
Повний текст джерелаGeorge, R. J. D. "High frequency ventilation in conscious, breathing subjects." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599355.
Повний текст джерелаMortimer, A. J. "High frequency jet ventilation : Mechanics and gas exchange." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373490.
Повний текст джерелаChartrand, Daniel 1955. "Ventilation by high-frequency body-surface oscillation in rabbits." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75917.
Повний текст джерелаWarlick, Kathleen Marie 1956. "Synchronized high frequency jet ventilation during extracorporeal shock wave lithotripsy." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276694.
Повний текст джерелаAlzahrani, Waleed A. "Comparison of Albuterol Delivery between High Frequency Oscillatory Ventilation and Conventional Mechanical Ventilation in a Simulated Adult Lung Model using Different Compliance Levels." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/rt_theses/10.
Повний текст джерелаSehati, Sepehr. "Automated monitoring of carbon dioxide concentration and control of airway pressure during high frequency jet ventilation." Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292603.
Повний текст джерелаEngland, John. "The Effect of Compliance Changes on Delivered Volumes in an Adult Patient Ventilated with High Frequency Oscillatory Ventilation: A Bench Model." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/rt_theses/2.
Повний текст джерелаAljamhan, Essam Ali. "How Does Alteration of Airway Resistance Affect Delivered Tidal Volume in Adult Patients Receiving High-Frequency Oscillatory Ventilation?" Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/rt_theses/1.
Повний текст джерелаBurkhardt, Wolfram, Florian Kurth, Manuela Pitterle, Nicola Blassnig, Andreas Wemhöner, and Mario Rüdiger. "Continuous Noninvasive Monitoring of Lung Recruitment during High-Frequency Oscillatory Ventilation by Electrical Impedance Measurement: An Animal Study." Karger, 2013. https://tud.qucosa.de/id/qucosa%3A71625.
Повний текст джерелаSmith, Norman Alan. "The steady-state and post-ignition transient luminous behaviour of the tubular fluorescent lamp operating throughout the dimmed mode range using high frequency dimming." Thesis, University of Sheffield, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387764.
Повний текст джерелаFors, Diddi. "Gas Embolism in Laparoscopic Liver Surgery." Doctoral thesis, Uppsala universitet, Anestesiologi och intensivvård, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-171797.
Повний текст джерелаPires, Rafaelle Batistella. "Comparação entre posição prona e posição supina, associadas à ventilação oscilatória de alta frequência e ventilação mecânica convencional protetora, em modelo experimental de lesão pulmonar aguda." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/152939.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A Síndrome do Desconforto Respiratório Agudo (SDRA) cursa com alta morbi-mortalidade apesar dos avanços no entendimento de sua fisiopatologia e tratamento. A terapia ventilatória baseia-se na proteção pulmonar, sendo a ventilação oscilatória de alta frequência (VOAF) uma opção de método protetor. A posição prona (PP) é terapia adjuvante que possibilita homogeneização da distribuição do volume corrente (VC) e promove recrutamento alveolar. O objetivo do estudo foi investigar o efeito da posição prona associada à VOAF e ventilação mecânica convencional (VMC) protetora sobre a oxigenação, inflamação, dano oxidativo e histologia pulmonares, comparando-a à posição supina em ambos os modos ventilatórios. Foram instrumentados 75 coelhos com traqueostomia e acessos vasculares. A lesão pulmonar aguda (LPA) foi induzida por lavagem traqueal de salina aquecida (30mL/Kg, 38°C). Os animais foram então aleatorizados em cinco grupos (n=15): 1) GC (Controle): animais sadios em VMC protetora basal; 2) GVMS: animais com LPA em VMC protetora e posição supina; 3) GVMP: animais com LPA em VMC protetora e posição prona; 4) GVAFS: animais com LPA em VOAF e posição supina; 5) GVAFP: animais com LPA em VOAF e posição prona. Após, foram submetidos a quatro horas de VMC protetora (modo pressão regulada-volume controlado, PEEP 10 cmH2O, VC 6mL/kg, Ti 0,5s, FR 40 rpm e FiO2 1) ou VOAF (MAP 15 mmHg, FR 10Hz, amplitude 22 e FiO2 1). O nível de significância foi de 5%. Após a indução, os grupos apresentaram comportamentos semelhantes, com diminuição da relação PaO2/FiO2 e da complacência pulmonar, e aumento do índice de oxigenação (IO) e da pressão média de via aérea (p > 0,05). Ao final do experimento, houve aumento da PaO2/FiO2 nos grupos VOAF comparado aos grupos em VMC (p < 0,05). Houve queda do IO para os grupos em VOAF comparados ao GVMS (p < 0,05), porém o GVMP não diferiu deles (p > 0,05). Não houve diferença estatística quanto à contagem de células polimorfonucleares no lavado broncoalveolar (BAL) nos grupos com LPA. Não houve diferença estatística entre os grupos com lesão para a medida de TNF-alfa no plasma e para sua expressão gênica em tecido pulmonar. Entretanto, a medida de TNF-alfa no lavado broncoalveolar (BAL) e no tecido pulmonar no grupo GVMP foi menor, assemelhando-se ao controle (p > 0,05). Não houve diferença no dano oxidativo avaliado no tecido pulmonar entre os grupos (p > 0,05) e, também, na comparação entre regiões ventral e dorsal dos pulmões. O escore de lesão histológica foi menor nos grupos em VOAF, efeito potencializado no grupo em prona quando comparado aos grupos em VMC (GC = GVAFP < GVMS = GVMP), sem diferença na regionalização pulmonar. Concluimos que, em modelo de LPA por lavagem alveolar com salina aquecida em coelhos: a VOAF melhora a oxigenação quando comparados à VMC; na VMC, a PP atenua a lesão inflamatória avaliada pela medida de TNF-alfa no BAL e tecido pulmonar; os modos ventilatórios e as posições não modificam o grau de estresse oxidativo quando avaliados pelo método de malondialdeído; a VOAF melhora o escore histopatológico de lesão pulmonar, independemente da posição, mas a associação de VOAF e PP atenua a lesão histopatológica quando comparada com a VMC protetora, seja em posição prona ou supina.
Acute Respiratory Distress Syndrome (ARDS) presents with high morbidity and mortality despite advances in the understanding of its pathophysiology and treatment. Ventilatory therapy is based on the intention of injuring less, with high frequency oscillatory ventilation (HFOV) being a protective method option. Prone position (PP) is an adjuvant therapy that enables homogenization of volume tidal (VT) distribution and promotes alveolar recruitment. The aim of this study was to investigate the effects of prone position associated with HFOV and protective conventional mechanical ventilation (CMV) on oxygenation and lung inflammation, oxidative damage and histology, comparing it with the supine position in both ventilatory modes. Seventy five rabbits were submitted to tracheostomy and vascular accesses. ALI was induced by tracheal infusion of heated saline (30mL/kg, 38° C). The subjects were then ramdomized in five groups (n=15): 1) CG (Control): healthy animals in basal protective CMV; 2) MVSG: animals with ALI in protective CMV and supine position; 3) MVPG animals with ALI in protective CMV and prone position; 4) HFSG: animals with ALI in HFOV and supine position; 5) HFPG: animals with ALI in HFOV and prone position. After that, they were submitted to four hours of protective VMC (PRV mode, PEEP 10 cmH2O, VC 6ml/kg, Ti 0,5s, FR=40 rpm and FiO2 1) or HFOV (MAP 15 mmHg, FR 10 Hz, amplitude 22 and FiO2 1). The level of significance was 5%. After induction, the groups presented similar behaviors, with a decrease in the PaO2/FiO2 ratio and lung compliance, and an increase in oxygenation index (OI) and mean airway pressure (p > 0.05). At the end of experimental time, PaO2/FiO2 increased in the HFOV groups compared to the CMV groups (p < 0.05). There was a decrease in OI for HFOV groups compared to MVSG (p < 0.05), but MVPG did not differ from them (p > 0.05). There was no statistically significant difference in polymorphonuclear cell counts in bronchoalveolar lavage (BAL) in the groups with ALI. There was no difference between ALI groups regarding the TNF-alfa dosage in plasma and its gene expression in lung tissue. However, TNF-alpha measurement in BAL and in lung tissue was smaller, resembling control (p > 0.05). There was no difference in the oxidative damage assessed in the lung tissue between the groups (p > 0.05), nor between the lung regions. The histological damage score was lower in the HFOV groups, potentiated effect in the prone group when compared to the CMV groups (CG = HFPG < MVSG = MVPG), no difference in pulmonary regionalization. We conclude that, in the model of ALI induced by alveolar lavage with heated saline in rabbits: HFOV improves oxygenation if compared to CMV; PP in CMV attenuates lung inflammation, evaluated by TNF-alfa dosage in BAL and in lung tissue; ventilatory modes and positions don’t modify the oxidative stress whan evaluated by malondialdehyde method; HFOV improves histopathological lung lesion score, regardless of position, but HFOV and prone position association attenuates histopathological injury compared to protective CMV, either in the prone or supine positions.
FAPESP: 2010/06242-8
Thacker, Shreya. "The Independent Effect of Three Inline Suction Adapters and Lung Compliance change on Amplitude and delivered Tidal Volume during High Frequency Oscillatory Ventilation in an adult patient with ARDS: Bench Model." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/rt_theses/6.
Повний текст джерелаCordioli, Ricardo Luiz. "Efeitos fisiológicos da ventilação de alta frequência usando ventilador convencional em um modelo experimental de insuficiência respiratória grave." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/5/5150/tde-10102012-111936/.
Повний текст джерелаIntroduction: Acute respiratory distress syndrome (ARDS) has a high incidence and mortality between critical ill patients. The mechanical ventilation is the most important support for these patients with ARDS. However, until now there is an important debate about how is the best ventilatory strategy to use, because the mechanical ventilation if not well set can cause lung injury and increase mortality. The use of high tidal volume is one of the most important mechanics of ventilation induced lung injury and there is evidence in the literature that using low tidal volume is a protective ventilation with better survival. Objective: To explore if high frequency positive pressure ventilation (HFPPV) delivered by a conventional ventilator (Servo-300) is able to allow further tidal volume reductions and to stabilize PaCO2 in a severe acute respiratory distress syndrome (ARDS) model initially ventilated with a protective ventilation. Methods: A prospective and experimental laboratory study where eight Agroceres pigs were instrumented and followed by induction of acute lung injury with sequential pulmonary lavages and injurious ventilation. Afterwards, the animals were ventilated with a tidal volume of 6 mL/kg, followed by a randomized sequence of respiratory rates (30, 60, 60 with pauses of 10 and 30% of the inspiratory time, 90, 120, 150, 60 with alveolar recruitment maneuver and PEEP titration and 5 Hertz of HFOV), until PaCO2 stabilization between 57 63 mmHg for 30 minutes. The Servo-300 ventilator was used for HFPPV and the ventilator SensorMedics 3100B was used for HFOV. Data are shown as median (P25th,P75th). Measurements and Main Results: Animals weight was 34 [29,36] kg. After lung injury, the P/F ratio, pulmonary shunt and static compliance of animals were 92 [63,118] mmHg, 26 [17,31] % and 11 [8,14] mL/cmH2O respectively. The total PEEP used was 14 [10,17] cmH2O throughout the experiment. From the respiratory rates of 35 (while ventilating with 6 mL/kg) to 150 breaths/ minute, the PaCO2 was 81 [78,92] mmHg and 60 [58,63] mmHg (P=0.001), the tidal volume progressively felt from 6.1 [5.9,6.2] to 3.8 [3.7,4.2] mL/kg (P<0.001), the plateau pressure was 29 [26,30] and 27[25,29] cmH2O (P=0.306) respectively. There were no detrimental effects in the hemodynamics and blood oxygenation, while the animals were using a FiO2 = 1. Conclusions: During protective mechanical ventilation, HFPPV delivered by a conventional ventilator in a severe ARDS swine model allows further tidal volume reductions. This strategy also allowed the maintenance of PaCO2 in clinically acceptable levels
Bauer, Katrin. "Characterization of mass transport in the upper human airways." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2012. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-83405.
Повний текст джерелаKünstliche Beatmung ist meist eine lebensrettende Maßnahme. Aufgrund der räumlich anisotropen und inhomogenen Eigenschaften der Lunge kann die Beatmung jedoch auch zu einer Schädigung der Lunge führen. Daraus ergibt sich die Forderung einer „Protektiven Beatmung“. Ein erster Schritt dahingehend ist ein verbessertes Verständnis der Atmung und Beatmung am Beispiel der gesunden sowie kranken, teilweise kollabierten Lunge. Dies ist das Ziel der Arbeit. Hierfür wurde ein realistisches Modell der oberen Atemwege (Tracheobronchialbaum) angefertigt. An diesem Modell können sowohl experimentelle als auch numerische Untersuchungen durchgeführt werden. Experimentell wurde die Strömung mittels Particle Image Velocimetry (PIV) untersucht, wobei neue Details bezüglich der auftretenden Strömungsmuster für unterschiedliche Frequenzen gefunden wurden. Numerische Strömungsberechnungen stimmen gut mit den experimentellen Ergebnissen überein. Dreidimensionale Strömungsstrukturen sowie die Entwicklung von Sekundärwirbeln in der Lunge konnten erklärt werden. Eine Studie am kranken, teilweise kollabierten Lungenmodell zeigte, dass mit steigender Frequenz kollabierte Bereiche wiedereröffnet werden können. Höhere Frequenzen führen weiterhin zu einer Homogenisierung der Massenstromverteilung in der Lunge
Volpe, Márcia Souza. "Estudo de três estratégias de ventilação artificial protetora: alta freqüência, baixa freqüência e baixa freqüência associada à insuflação de gás traqueal, em modelo experimental de SARA." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-11082010-102833/.
Повний текст джерелаIntroduction: One of the major goals in ARDS is to find the best protective mechanical ventilation strategy, which minimizes lung stress and optimizes gas exchange. Theoretically, these two goals can be accomplished by simultaneously avoiding alveolar overdistension and cyclic collapse of unstable alveolar units. Pushing further the rationale of this strategy, two new strategies have been proposed: high frequency oscillatory mechanical ventilation (HFOV) and intra-tracheal gas insufflation (TGI) associated with permissive hypercapnia and conventional frequencies. Objective: To determine which of the three protective modalities of mechanical ventilation, HFOV, low-frequency-protective ventilation (LFV), or LFV associated with tracheal gas insufflation (TGI), was the most protective strategy in an ARDS rabbit model during six hours of mechanical ventilation. Material and methods: The animals (n = 45) were submitted to repeated saline lavage until PaO2 < 100 mmHg. Immediately after lung injury, a P/V curve was obtained to calculate inspiratory/expiratory work and energy dissipated during lung inflation. Thereafter, the animals were randomized into one of three groups: LFV, HFOV or TGI. The optimal PEEP or PMEAN was obtained during a PEEP/PaO2 (or PMEAN/PaO2) curve which was preceded by a recruiting maneuver. The animals of the LFV and TGI groups were initially ventilated in PCV with diving pressure = 8 cmH2O and frequency = 60 b/m. The only initial difference between these two arms was that the TGI group had a continuous tracheal flow = 1 L/min. The animals in the HFOV were initially ventilated with an oscillatory pressure amplitude = 45 cmH2O and frequency = 10 Hz. All animals were ventilated with FiO2 = 1.0. Driving pressure was then adjusted in LFV and TGI groups to maintain a PaCO2 = 90-110 mmHg, while in HFO the pressure amplitude was adjusted to maintain a PaCO2 = 45-55 mmHg. At the end of the experiment, after 6 hours of ventilation, another P/V curve was obtained. BAL and bloods samples were drawn before and after the period of ventilation to determine IL-8 levels. The left lung was processed for histological analysis and for wet weight/dry weight (ww/dw) ratio. Results: We observed no differences in PaO2 among the groups. PaCO2 was significantly lower at HFO (59 ± 3 mmHg) when compared with LFV (99 ± 4 mmHg) and TGI (80 ± 3 mmHg) groups. Tidal volume was significantly lower in TGI and HFO groups when compared with LFV group. Soon after injury, all groups required similar energy for lung inflation (inspiratory work), but the VP group was the only one not presenting any improvement in this parameter after 6 hours (P<0.001). Concerning the expiratory work, the VP strategy was the only one presenting an increase in the expiratory work along the 6 hours (P<0.001). The TGI and HFOV groups showed the highest polymorphonuclear cell concentration in lung tissue (P=0.008) and trends towards a higher surface/volume index (P=0.14), higher IL8 gradient (difference between IL8 in BAL and plasma) and lower ww/dw ratio at the end of 6 hours of ventilation (P=0.17). Discussion: The lower energy for lung inflation after six hours of ventilation reflected the reduction of opening pressures and better surfactant function during ventilation under TGI and HFOV strategies. The increase in expiratory work during the VP strategy further suggests that the surfactant quality deteriorated under this strategy. In the TGI and HFOV groups, the higher concentration of polymorphonuclear cells and the trend towards a higher IL8 gradient between the lung and blood may suggest a better integrity of the alveolar-capillary membrane, leading to less release of compartmentalized mediators within the alveolar space. Besides the higher tidal volumes used during VP, this strategy required inspiratory pressures progressively higher along the hours, due to frequent and necessary adjustments of tidal volumes or pressures according to the gas-exchange requirements. Conclusion: An aggressive reduction of tidal volume and driving pressures was beneficial during protective strategies, even when an optimization of lung recruitment was already in place. The TGI strategy showed to be an attractive alternative to HFOV, presenting some advantages in terms of implementation and predictability of response.
Hsing, Shu-Chen, and 邢淑珍. "The Outcomes Analysis of Using High Frequency Oscillatory Ventilation in One Medical Centerof Southern Taiwan." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/7rswd9.
Повний текст джерела嘉南藥理大學
醫務管理系
102
Purpose: High frequency oscillatory ventilator (HFOV) reduces lung injury from conventional ventilation and improves oxygenation in patients with acute respiratory distress syndrome (ARDS). The purpose of this study is to investigate factors influencing the effectiveness of HFOV in adult patients. Method: We performed a retrospective study on adult patients, who was treated with HFOV during January 2006 to December 2010, hospitalized in ICU of a medical center in southern Taiwan. The information of gender, age, diagnosis, ICU admission type, APACH II, days of ICU stay, ventilator days were collected. Additionally, the survival of patients, parameters of respiratory system between conventional mechanical ventilation and HFOV were compared using SPSS 17.0 for windows (An IBM Company). In the first part, we used descriptive statistics to analyze background information of patients. Continueously, we used chi-square and the Nonparametric Wilcoxon rank sum test to compare the differences of factors between survivors and non-survivors. The respiratory gas exchange and the parameters of respiratory system before and after using HFOV were analyzed by the nonparametric Wilcoxon signed rank test. The risk factors for mortality were calculated by multiple logistic regression analysis. Result: The data of study were collected from 77 patients. The improvement (P<0.05) of FiO2, P/F ratio, pH, and PaCO2 in ARDS patients was observed significantly within 72 hours after treating with HFOV. The mean airway pressure (mPaw) was increased significantly, respectively. The significant differences was showed in patients ≧60 years (35% vs. 64.9%,P<0.05),HFOV hours (129.8±79.7 vs. 99.6±128.1, P<0.05), mean arterial pressure (91.7±20 vs. 80.1±19.3 mm Hg, P<0.05) between survivors and non-survivors. Furthermore, the pH level of non-survivors after treating with HFOV was significantly lower than survivors (7.34±0.09 vs. 7.28±0.12, P <0.05). however, There is no significant difference in mPaw, oxygen concentration (FiO2), PaCO2, and Oxygenation index between the two groups. Conclusion: HFOV improved gas exchange and increased the P/F ratio and pH level in adult patients. Furthermore, levels of FiO2 and PaCO2 were decreased in ARDS patients, respectively. The efficiency of HFOV peaked at 24 hours and remained constant through 72 hours. Patients with better pulmonary gas exchange before HFOV treated had better prognosis, indicating that early HFOV treated was associated with better outcomes.
Tingay, David Gerald. "The relationship between the volume state of the lung, gas exchange and lung mechanics during high-frequency oscillatory ventilation." 2008. http://repository.unimelb.edu.au/10187/2810.
Повний текст джерелаBauer, Katrin. "Characterization of mass transport in the upper human airways." Doctoral thesis, 2011. https://tubaf.qucosa.de/id/qucosa%3A22799.
Повний текст джерелаKünstliche Beatmung ist meist eine lebensrettende Maßnahme. Aufgrund der räumlich anisotropen und inhomogenen Eigenschaften der Lunge kann die Beatmung jedoch auch zu einer Schädigung der Lunge führen. Daraus ergibt sich die Forderung einer „Protektiven Beatmung“. Ein erster Schritt dahingehend ist ein verbessertes Verständnis der Atmung und Beatmung am Beispiel der gesunden sowie kranken, teilweise kollabierten Lunge. Dies ist das Ziel der Arbeit. Hierfür wurde ein realistisches Modell der oberen Atemwege (Tracheobronchialbaum) angefertigt. An diesem Modell können sowohl experimentelle als auch numerische Untersuchungen durchgeführt werden. Experimentell wurde die Strömung mittels Particle Image Velocimetry (PIV) untersucht, wobei neue Details bezüglich der auftretenden Strömungsmuster für unterschiedliche Frequenzen gefunden wurden. Numerische Strömungsberechnungen stimmen gut mit den experimentellen Ergebnissen überein. Dreidimensionale Strömungsstrukturen sowie die Entwicklung von Sekundärwirbeln in der Lunge konnten erklärt werden. Eine Studie am kranken, teilweise kollabierten Lungenmodell zeigte, dass mit steigender Frequenz kollabierte Bereiche wiedereröffnet werden können. Höhere Frequenzen führen weiterhin zu einer Homogenisierung der Massenstromverteilung in der Lunge.