Objective To determine the cardiopulmonary and blood gas status of elephants during chemical capture (immobilisation) with a thiafentanil-azaperone drug combination kept in lateral recumbency. Study design Prospective descriptive study. Animal population Ten free-ranging adult African elephant bulls (estimated weight range 3000 to 6000 kg). Methods Elephants were immobilised using a thiafentanil (15-18 mg) and azaperone (75-90 mg) by darting from a helicopter. Once recumbent, the tidal volume, minute volume, end-tidal carbon dioxide, arterial blood pressure and pulse rate were recorded immediately after instrumentation and at five-minute intervals until T20. Arterial and venous blood gases were analysed at the time of initial instrumentation and at 20 minutes. On completion of the data collection, the thiafentanil was antagonised using naltrexone (10 mg mg-1 thiafentanil). A stopwatch was used to record time to recumbency (dart placement to recumbency) and time to recovery (administering antagonist to standing). Data was checked for normality and was found to be parametric. Data were compared using a one-way analysis of variance and reported as mean (± SD). Results All elephants were successfully immobilised and all physiological variables remained constant with minimal non-significant variation over time. Average time to recumbency was 12.5 minutes. The estimated expiratory tidal volume was 21 (± 6) L breath-1 or 4.8 ± 0.8 mL kg-1, and the measured minute volume was 103 (± 31) L minute-1. The heart and respiratory rates were 49 (±6) beats and 5 (± 1) breaths minute-1, respectively. The mean arterial blood pressure was 153 (± 31) mmHg. The elephants were acidaemic (pH 7.18 ±0.06; bicarbonate ion 20 ±4 mmol L-1; lactate 11 ± 4 mmol L-1), mildly hypoxemic (PaO2 68 ± 15 mmHg) and mildly hypercapnic (PaCO2 52 ± 7 mmHg). Average time to recovery was 2.2 minutes. Conclusion and clinical relevance African elephant bulls can be successfully immobilised using thiafentanil-azaperone. Recumbency was rapid, the cardiopulmonary variables were stable and within acceptable ranges, and recovery was rapid and complete. Mild hypoxaemia and hypercapnia were evident, but does not necessarily require oxygen supplementation. / Dissertation (MSc)--University of Pretoria, 2020. / Companion Animal Clinical Studies / MSc / Unrestricted

Administration of nasal cannula therapy tasks providers with periodically monitoring their patients and adjusting settings according to patient needs. Conventionally, providers monitor a patient's oxygen demand using pulse oximetry and a qualitative assessment of the patient's work of breathing. The motivation for this research is to augment the traditional qualitative assessment of work of breathing with a quantitative measurement of a patient's tidal volume, the volume of air inhaled with each breath. This thesis presents a novel approach to measure tidal volume using a nasal cannula with built-in pressure sensors. Pressure waveforms obtained from continuous measurement of the pressure at the tip of the cannula are used to estimate nasal flowrates, and these nasal flowrates are time-integrated to estimate tidal volumes. Computational fluid dynamics (CFD) models were used to simulate fluid flow in a simplified nasal passage undergoing nasal cannula therapy. These simulations used a range of flow conditions characteristic of both low-flow and high-flow nasal cannula treatments. The simulations produced a transformation from cannula tip pressure to instantaneous nasal flowrate, and this transformation was evaluated using a matching empirical experiment. This empirical experiment used a matching physical geometry with a similar range of flow conditions, and the transformation obtained from CFD was able to estimate the actual tidal volumes with 85% accuracy. This study showed that continuous pressure measurement at the tip of a nasal cannula produces enough information to estimate nasal flowrates and tidal volumes. No similar studies were found during the literature review, so an accuracy of 85% is promising for this stage. If this technique could be made more accurate and deployed in an unobtrusive way, the resulting nasal cannula device could be used to continuously, comfortably monitor patients' tidal volumes. / Master of Science / Oxygen therapy is the most common prescription in hospitals across the United States, and the most common form of oxygen therapy is nasal cannula therapy. Administration of nasal cannula therapy requires providers to periodically assess their patients' oxygen saturations and work of breathing. Oxygen saturation can be quantitatively monitored using pulse oximetry but work of breathing must be qualitatively monitored using visual exams or walking tests. The motivation of this research is to augment this qualitative assessment with a quantitative metric. In our research, we chose the volume of inhaled air (the "tidal volume") as a proxy metric for a patient's work of breathing. This thesis presents our attempt to use a nasal cannula augmented with pressure sensors to estimate the tidal volume of a mannequin undergoing nasal cannula therapy. Our concept is that more intense inhalations/exhalations produce larger pressure swings at the tip of the nasal cannula. For this proof-of-concept study, a simplified nasal passage geometry was used. Pressure waveforms obtained from continuous measurement of the pressure at the tip of the cannula are used to estimate nasal flowrates, and these nasal flowrates are time-integrated to estimate tidal volumes. Computational fluid dynamics (CFD) simulations were used to predict how the cannula tip pressure changes as a function of nasal flowrates and cannula flowrates, then this relationship was tested using a matching empirical experiment. This matching empirical experiment showed that our technique of estimating tidal volumes was 85% accurate. This study showed that continuous pressure measurement at the tip of a nasal cannula produces enough information to estimate nasal flowrates and tidal volumes. No similar studies were found during the literature review, so an accuracy of 85% is promising for this stage. If this technique could be made more accurate and deployed in an unobtrusive way, the resulting nasal cannula device could be used to continuously, comfortably monitor patients' tidal volumes.

A fita nasal é amplamente utilizada em equinos durante o exercício, porém seus resultados são controversos e pouco conhecidos em animais que disputam provas de resistência. Os objetivos desse trabalho foram verificar se o uso da fita nasal influencia parâmetros durante o exercício predominantemente aeróbico, como frequência respiratória, volume tidal, volume minuto, tempos de inspiração e expiração, população de células por meio de lavado broncoalveolar, frequência cardíaca e lactato sanguíneo. Foram utilizados seis equinos da raça Árabe que realizaram dois testes de longa duração em esteira, sendo um teste com fita e outro sem a fita nasal. Durante os testes eram realizadas coletas de sangue, espirometria com obtenção de curvas de fluxo e volume respiratório, e registro da frequência cardíaca por meio de frequencímetro. Duas horas após o término do exercício foi realizado lavado broncoalveolar para realização de citologia da secreção pulmonar. Não houveram diferenças entre os parâmetros ventilatórios analisados entre os animais quando correram com ou sem a fita nasal. Entretanto, a frequência cardíaca foi em média menor durante o exercício nos animais que se exercitaram com a fita nasal (p<0,05), podendo indicar uma melhor oferta de oxigênio durante o exercício de longa duração com o uso da fita nasal, apesar de não encontrarmos alterações nos parâmetros de fluxo e volume respiratório. Na avaliação citológica do conteúdo do lavado broncoalveolar, foi verificada maior porcentagem de neutrófilos após o exercício nos animais que se exercitaram com a fita nasal (p<0,05), indicando que o turbilhonamento na passagem do ar através da cavidade nasal pode ter diminuído permitindo que partículas maiores se depositassem em porções mais distais do sistema respiratório, induzindo uma resposta neutrofílica mais intensa. O uso da fita nasal parece influenciar alguns parâmetros durante e após o exercício em animais que realizam provas de longa duração. Outros estudos devem ser realizados para verificar se essa influência pode melhorar o desempenho desses animais em exercícios predominantemente aeróbicos / The nasal strip is widely used in horses during exercise, but the results are controversial and little known in animals that compete for endurance events. The aim of this study was to determine whether the use of nasal strips influence parameters during predominantly aerobic exercise, such as respiratory frequency, tidal volume, minute ventilation, inspiratory and expiratory times, population of cells by bronchoalveolar lavage, heart rate and blood lactate. Six Arabian horses were submitted to two low intensity tests on a treadmill, one of them with nasal strip and one without nasal strip. During the tests were carried out blood samples, airflow and volume curves with spirometry mask, and heart rate was recorded through heart rate monitor. Two hours after the exercise was performed bronchoalveolar lavage to perform cytology of pulmonary secretions. There were no differences among ventilatory parameters analyzed when the horses performed the exercise with or without the nasal strip. However, heart rate was lower on average during the exercise when the horses were exercised with nasal strip (p <0.05), which may indicate a better supply of oxygen during the low intensity exercise with the use of nasal strip, despite we did not find changes in the airflow and respiratory volume parameters. In cytological evaluation of the content of bronchoalveolar lavage, increased percentage of neutrophils was observed after exercise in animals with nasal strip (p <0.05), indicating that turbulence in the airflow through the nasal cavity may have diminished allowing larger particles to be deposited in distal portions of the respiratory system, inducing a more intense neutrophilic response. The use of nasal strips appears to influence some parameters during and after exercise in horses that perform low intensity and endurance tests. Further studies should be conducted to verify that this influence can improve the performance of these horses in predominantly aerobic exercises

Concerns exist regarding the ability of HFOV to provide the needed lung protective ventilation for adult patients with ARDS. HFOV is increasingly being used as a lung protecting ventilation mode even if some of its protective attributes may be lost as the airway resistance (Raw) increases or decreases. In fact, in cases of shifting air resistance, HFOV may have caused lung injury. PURPOSE: The purpose of this study was to investigate the effect of airway resistance on tidal volume (Vt) delivered by HFOV to adult patients. Also, the study intended to determine direction for volume change when resistance increases or decreases. METHODS: An in vitro model was used to simulate an adult passive patient with ARDS using a breathing simulator (Active Servo Lung 5000, Ingmar Medical, Pittsburgh, PA, USA). Adjustable resistance and compliance for each lung was used. The resistance levels of 15, 30, 45 (cm H2O/L/sec) were used for upper and lower Raw and CL was fixed at 40 mL/cm H2O. The ventilator (Sensormedics 3100B) was set to MAP = 35 cm H2O, to insp-time of 33%, to bias flow =30 L/min, to delta-P of 80, and to 50% oxygen. Vt was recorded (n=3) for each Raw, and the data was collected on the host computer. Approximately 200-250 breaths of data for each Raw were captured via the ASL software and then converted to Excel for analysis. An average of 80 breathes (following the steady Vt level) was used in each analysis. DATA ANALYSIS: The data analysis was performed with one way ANOVA and with a post hoc Bonferroni test in order to determine the statistical significance of the delivered Vt with each Raw. A probability of (p < 0.05) was accepted as statistically significant. RESULTS: The descriptive statistics of the average delivered Vt with regard to each Raw (15, 30, 45 cm H2O/L/sec) were the number of experiments (n=3), mean Vt (93.52, 89.09, 85.99 mL), and standard deviations (SD) (1.38, 1.11, 1.10) respectively. There was an inverse relationship between tidal volume and airway resistance during HFOV. With all other variables kept constant, higher resistance caused less volume, whereas lower resistance caused more volume. The one-way ANOVA test showed that there were significant differences between the delivered tidal volumes. When the post hoc Bonferroni test was used, the data showed significant differences between airway resistances of 15 cm H2O/L/sec and 30 cm H2O/L/sec and between 15 cm H2O/L/sec and 45 cm H2O/L/sec. In contrast, no significant differences were found between airway resistances of 30 cm H2O/L/sec and 45 cm H2O/L/sec. CONCLUSION: Vt is not constant during HFOV. Airway resistance is one of the determinants of delivered tidal volume in adults with ARDS during HFOV. Airway resistance should be an important factor in ventilator management and in clinical experiments of patients on HFOV. Without a proper Vt measurement device HFOV should not be used as lung protective ventilation for adult patients with ARDS.

A fita nasal é amplamente utilizada em equinos durante o exercício, porém seus resultados são controversos e pouco conhecidos em animais que disputam provas de resistência. Os objetivos desse trabalho foram verificar se o uso da fita nasal influencia parâmetros durante o exercício predominantemente aeróbico, como frequência respiratória, volume tidal, volume minuto, tempos de inspiração e expiração, população de células por meio de lavado broncoalveolar, frequência cardíaca e lactato sanguíneo. Foram utilizados seis equinos da raça Árabe que realizaram dois testes de longa duração em esteira, sendo um teste com fita e outro sem a fita nasal. Durante os testes eram realizadas coletas de sangue, espirometria com obtenção de curvas de fluxo e volume respiratório, e registro da frequência cardíaca por meio de frequencímetro. Duas horas após o término do exercício foi realizado lavado broncoalveolar para realização de citologia da secreção pulmonar. Não houveram diferenças entre os parâmetros ventilatórios analisados entre os animais quando correram com ou sem a fita nasal. Entretanto, a frequência cardíaca foi em média menor durante o exercício nos animais que se exercitaram com a fita nasal (p&lt;0,05), podendo indicar uma melhor oferta de oxigênio durante o exercício de longa duração com o uso da fita nasal, apesar de não encontrarmos alterações nos parâmetros de fluxo e volume respiratório. Na avaliação citológica do conteúdo do lavado broncoalveolar, foi verificada maior porcentagem de neutrófilos após o exercício nos animais que se exercitaram com a fita nasal (p&lt;0,05), indicando que o turbilhonamento na passagem do ar através da cavidade nasal pode ter diminuído permitindo que partículas maiores se depositassem em porções mais distais do sistema respiratório, induzindo uma resposta neutrofílica mais intensa. O uso da fita nasal parece influenciar alguns parâmetros durante e após o exercício em animais que realizam provas de longa duração. Outros estudos devem ser realizados para verificar se essa influência pode melhorar o desempenho desses animais em exercícios predominantemente aeróbicos / The nasal strip is widely used in horses during exercise, but the results are controversial and little known in animals that compete for endurance events. The aim of this study was to determine whether the use of nasal strips influence parameters during predominantly aerobic exercise, such as respiratory frequency, tidal volume, minute ventilation, inspiratory and expiratory times, population of cells by bronchoalveolar lavage, heart rate and blood lactate. Six Arabian horses were submitted to two low intensity tests on a treadmill, one of them with nasal strip and one without nasal strip. During the tests were carried out blood samples, airflow and volume curves with spirometry mask, and heart rate was recorded through heart rate monitor. Two hours after the exercise was performed bronchoalveolar lavage to perform cytology of pulmonary secretions. There were no differences among ventilatory parameters analyzed when the horses performed the exercise with or without the nasal strip. However, heart rate was lower on average during the exercise when the horses were exercised with nasal strip (p &lt;0.05), which may indicate a better supply of oxygen during the low intensity exercise with the use of nasal strip, despite we did not find changes in the airflow and respiratory volume parameters. In cytological evaluation of the content of bronchoalveolar lavage, increased percentage of neutrophils was observed after exercise in animals with nasal strip (p &lt;0.05), indicating that turbulence in the airflow through the nasal cavity may have diminished allowing larger particles to be deposited in distal portions of the respiratory system, inducing a more intense neutrophilic response. The use of nasal strips appears to influence some parameters during and after exercise in horses that perform low intensity and endurance tests. Further studies should be conducted to verify that this influence can improve the performance of these horses in predominantly aerobic exercises

INTRODUÇÃO: Picos de pressão inspiratória excessivos e elevados volumes correntes (VT) durante a ventilação manual podem iniciar a resposta inflamatória no pulmão do prematuro. A manobra de insuflação pulmonar sustentada (IPS) tem sido estudada como um procedimento para melhorar a aeração pulmonar imediatamente após o nascimento. OBJETIVO: Avaliar a influência do ventilador manual em T (peça T) e do balão autoinflável (BAI) nas variáveis de mecânica respiratória durante a ventilação manual e a manobra de IPS, além da influência do treinamento como instrutor do Programa de Reanimação Neonatal da Sociedade Brasileira de Pediatria (PRN-SBP), na qualidade da ventilação. MÉTODOS: Em um estudo experimental, prospectivo e randomizado, 114 indivíduos, entre instrutores e não instrutores do PRN-SBP, ventilaram um manequim neonatal intubado, equivalente a um recém-nascido de 2500 gramas, por períodos de três minutos, utilizando um BAI e a peça T. A escolha do primeiro equipamento foi feita por randomização e os operadores não tinham acesso aos dados de mecânica respiratória durante a gravação. Ao final da ventilação manual, foi solicitado que cada indivíduo realizasse uma manobra de IPS durante 10 segundos, a uma pressão de 20 cmH2O. Para cada parâmetro de mecânica respiratória obtido durante a ventilação manual e a IPS, foi realizada uma comparação direta entre os equipamentos, considerando a formação e o treinamento dos participantes. Os dados foram obtidos por um sistema informatizado que permitiu a análise posterior. RESULTADOS: Em relação à ventilação manual, foi encontrada uma diferença nos valores do VT e do TI entre os equipamentos. Com o uso do BAI o VT foi de 28,5 (12,6) mL, mediana (amplitude interquartil) no grupo instrutores e 31,6 (14,0) mL no grupo não instrutores, enquanto que com a peça T foi de 20,1 (8,4) mL e 22,3 (8,8) mL, respectivamente. O TI encontrado com o uso do BAI foi de 0,5 (0,2) segundos, mediana (amplitude interquartil), tanto para instrutores como para não instrutores, enquanto que com a peça T foi de 1,0 (0,6) segundos e 1,1 (0,9) segundos, respectivamente. Em ambos os parâmetros não foram observadas diferenças entre os grupos de profissionais. A capacidade do operador de manter uma pressão alvo de 20 cmH2O durante os 10 segundos de IPS foi avaliada através da área sob a curva de pressão (ASC), que foi 1,7 vezes maior com o uso da peça T em relação ao BAI (p < 0,05). A pressão inspiratória máxima aplicada para a realização da IPS foi maior com o uso do BAI, enquanto que a pressão média das vias aéreas, avaliada entre o início e o final dos 10 segundos de procedimento, foi maior com o uso da peça T. Novamente não foram observadas diferenças entre os grupos de profissionais. CONCLUSÃO: A peça T resultou em menores valores de VT e maiores valores de TI independente do treinamento como instrutor do PRNSBP. A peça T permitiu uma maior eficácia na realização da manobra de IPS, representada pela manutenção da pressão alvo pelo período desejado e por uma maior pressão média nas vias aéreas em relação ao BAI / INTRODUCTION: During manual resuscitation of neonates, excessive peak inspiratory pressure (PI) and high tidal volume (VT) may trigger an inflammatory response in the lungs. The sustained lung inflation (SLI) maneuver has been studied as a procedure to improve pulmonary aeration immediately after birth. OBJECTIVE: To assess the influence of a T-piece manual resuscitator versus a self-inflating bag (SIB) on respiratory mechanics during manual ventilation and the SLI maneuver and the influence of training as a Brazilian Society of Pediatrics Neonatal Resuscitation Program instructor on the quality of ventilation. METHODS: In this experimental, prospective, randomized trial, 114 operators, including Brazilian Society of Pediatrics Neonatal Resuscitation Program instructors and non-instructors, ventilated an intubated neonatal resuscitation trainer (equivalent to a 2500g neonate) for 3-minute periods using an SIB or a Tpiece device. The choice of first device was random, and operators had no access to respiratory mechanics data during recording. At the end of the manual ventilation period, each operator was asked to perform an SLI maneuver for 10 seconds at 20 cmH2O. For each respiratory mechanics parameter obtained during manual ventilation and SLI, a direct comparison between devices was performed, taking operator training into account. Data were obtained through a computerized system for later analysis. RESULTS: During manual ventilation, differences in VT and TI were found between the two devices. The SIB was associated with a median (interquartile range) VT of 28.5 (12.6) mL in the instructor group and 31.6 (14.0) mL in the noninstructor group, whereas the T-piece was associated with a VT of 20.1 (8.4) mL in the instructor group and 22.3 (8.8) mL in the non-instructor group. Regarding TI, the SIB was associated with a median (interquartile range) value of 0.5 (0.2) seconds in instructors and non-instructors alike, whereas the T-piece was associated with a value of 1.0 (0.6) seconds in the instructor group and 1.1 (0.9) seconds in the non-instructor group. No differences between the operator groups were found in either parameter. Operator ability to maintain a 20-cmH2O pressure during the 10-second SLI maneuver was assessed by the area under the pressure curve (AUC), which was 1.7 times greater with the T-piece device than with the SIB (p < 0.05). Peak PI during the SLI maneuver was higher with the SIB, whereas mean airway pressure, assessed between start and end of the 10-second maneuver, was higher with the T-piece. Again, there were no differences between the operator groups. CONCLUSION: The T-piece was associated with lower VT and higher TI values regardless of training as a Brazilian Society of Pediatrics Neonatal Resuscitation Program instructor. The T-piece provided greater efficacy in performing the SLI maneuver, as represented by maintenance of target pressure throughout the desired period and by a higher mean airway pressure as compared with SIB use

INTRODUÇÃO: Picos de pressão inspiratória excessivos e elevados volumes correntes (VT) durante a ventilação manual podem iniciar a resposta inflamatória no pulmão do prematuro. A manobra de insuflação pulmonar sustentada (IPS) tem sido estudada como um procedimento para melhorar a aeração pulmonar imediatamente após o nascimento. OBJETIVO: Avaliar a influência do ventilador manual em T (peça T) e do balão autoinflável (BAI) nas variáveis de mecânica respiratória durante a ventilação manual e a manobra de IPS, além da influência do treinamento como instrutor do Programa de Reanimação Neonatal da Sociedade Brasileira de Pediatria (PRN-SBP), na qualidade da ventilação. MÉTODOS: Em um estudo experimental, prospectivo e randomizado, 114 indivíduos, entre instrutores e não instrutores do PRN-SBP, ventilaram um manequim neonatal intubado, equivalente a um recém-nascido de 2500 gramas, por períodos de três minutos, utilizando um BAI e a peça T. A escolha do primeiro equipamento foi feita por randomização e os operadores não tinham acesso aos dados de mecânica respiratória durante a gravação. Ao final da ventilação manual, foi solicitado que cada indivíduo realizasse uma manobra de IPS durante 10 segundos, a uma pressão de 20 cmH2O. Para cada parâmetro de mecânica respiratória obtido durante a ventilação manual e a IPS, foi realizada uma comparação direta entre os equipamentos, considerando a formação e o treinamento dos participantes. Os dados foram obtidos por um sistema informatizado que permitiu a análise posterior. RESULTADOS: Em relação à ventilação manual, foi encontrada uma diferença nos valores do VT e do TI entre os equipamentos. Com o uso do BAI o VT foi de 28,5 (12,6) mL, mediana (amplitude interquartil) no grupo instrutores e 31,6 (14,0) mL no grupo não instrutores, enquanto que com a peça T foi de 20,1 (8,4) mL e 22,3 (8,8) mL, respectivamente. O TI encontrado com o uso do BAI foi de 0,5 (0,2) segundos, mediana (amplitude interquartil), tanto para instrutores como para não instrutores, enquanto que com a peça T foi de 1,0 (0,6) segundos e 1,1 (0,9) segundos, respectivamente. Em ambos os parâmetros não foram observadas diferenças entre os grupos de profissionais. A capacidade do operador de manter uma pressão alvo de 20 cmH2O durante os 10 segundos de IPS foi avaliada através da área sob a curva de pressão (ASC), que foi 1,7 vezes maior com o uso da peça T em relação ao BAI (p < 0,05). A pressão inspiratória máxima aplicada para a realização da IPS foi maior com o uso do BAI, enquanto que a pressão média das vias aéreas, avaliada entre o início e o final dos 10 segundos de procedimento, foi maior com o uso da peça T. Novamente não foram observadas diferenças entre os grupos de profissionais. CONCLUSÃO: A peça T resultou em menores valores de VT e maiores valores de TI independente do treinamento como instrutor do PRNSBP. A peça T permitiu uma maior eficácia na realização da manobra de IPS, representada pela manutenção da pressão alvo pelo período desejado e por uma maior pressão média nas vias aéreas em relação ao BAI / INTRODUCTION: During manual resuscitation of neonates, excessive peak inspiratory pressure (PI) and high tidal volume (VT) may trigger an inflammatory response in the lungs. The sustained lung inflation (SLI) maneuver has been studied as a procedure to improve pulmonary aeration immediately after birth. OBJECTIVE: To assess the influence of a T-piece manual resuscitator versus a self-inflating bag (SIB) on respiratory mechanics during manual ventilation and the SLI maneuver and the influence of training as a Brazilian Society of Pediatrics Neonatal Resuscitation Program instructor on the quality of ventilation. METHODS: In this experimental, prospective, randomized trial, 114 operators, including Brazilian Society of Pediatrics Neonatal Resuscitation Program instructors and non-instructors, ventilated an intubated neonatal resuscitation trainer (equivalent to a 2500g neonate) for 3-minute periods using an SIB or a Tpiece device. The choice of first device was random, and operators had no access to respiratory mechanics data during recording. At the end of the manual ventilation period, each operator was asked to perform an SLI maneuver for 10 seconds at 20 cmH2O. For each respiratory mechanics parameter obtained during manual ventilation and SLI, a direct comparison between devices was performed, taking operator training into account. Data were obtained through a computerized system for later analysis. RESULTS: During manual ventilation, differences in VT and TI were found between the two devices. The SIB was associated with a median (interquartile range) VT of 28.5 (12.6) mL in the instructor group and 31.6 (14.0) mL in the noninstructor group, whereas the T-piece was associated with a VT of 20.1 (8.4) mL in the instructor group and 22.3 (8.8) mL in the non-instructor group. Regarding TI, the SIB was associated with a median (interquartile range) value of 0.5 (0.2) seconds in instructors and non-instructors alike, whereas the T-piece was associated with a value of 1.0 (0.6) seconds in the instructor group and 1.1 (0.9) seconds in the non-instructor group. No differences between the operator groups were found in either parameter. Operator ability to maintain a 20-cmH2O pressure during the 10-second SLI maneuver was assessed by the area under the pressure curve (AUC), which was 1.7 times greater with the T-piece device than with the SIB (p < 0.05). Peak PI during the SLI maneuver was higher with the SIB, whereas mean airway pressure, assessed between start and end of the 10-second maneuver, was higher with the T-piece. Again, there were no differences between the operator groups. CONCLUSION: The T-piece was associated with lower VT and higher TI values regardless of training as a Brazilian Society of Pediatrics Neonatal Resuscitation Program instructor. The T-piece provided greater efficacy in performing the SLI maneuver, as represented by maintenance of target pressure throughout the desired period and by a higher mean airway pressure as compared with SIB use

Introduction: The use of high frequency oscillatory ventilation is increasing in treatment ofacute respiratory distress syndrome over the past decade. The technique of HFOV of ventilatingthe lungs at volumes less than the anatomical dead space calms the clinical concerns surroundingventilating stiff ARDS lungs with high pressures and volumes. This largely reduces theprobability of barotraumas and/or atelectrauma. Purpose: The study was on an in vitro bench model that answered the following researchquestions: 1. The effect of three inline closed suction adapters on delivered tidal volume duringHFOV with varying lung compliance 2. The effect of varying compliance on the amplitudedelivered by HFOV; and 3. The effect of compliance on tidal volume delivered by HFOV. Method: An in vitro bench model using high fidelity breathing simulator (ASL 5000, IngMarMedical) simulating an adult patient with ARDS was set up with 3100B SensorMedic highfrequency ventilator. The simulation included varying the compliance for each lung at 50, 40, 30and 20cmH2O while maintaining fixed resistance of 15 cmH2O/L/sec. The ventilator was set tothe following parameters: power of 6, frequency (f) of 5, inspiratory time (Ti) of 33%, bias flow(BF) of 30 LPM and oxygen concentration of 50%. The breathing simulator was connected withthe high frequency ventilator using a standard HFOV circuit and a size 8.0mm of endotrachealtube. Fourteen French Kimberly Clark suction catheters (with T and Elbow adapters) and Air-Life suction catheters (Y adapter) were placed in-line with the circuit successively to carry outthe study. Each run lasted for 1 minute after achieving stable state conditions. Thisapproximated to 300 breaths. The data was collected from the stimulator and stored by the hostcomputer. Data Analysis: The data was analyzed using SPSS v.11 to determine the statistical significance.A probability value (P value) of ≤ 0.001 was considered to be statistically significant. Results: The data analysis showed that Air-Life Y-adapter suction catheters caused the least lostin tidal volume when placed in line with HFOV and hence proved to be the most efficient. Thestudy also showed a direct relationship between amplitude and lung compliance i.e. an increasein lung compliance caused an associated increase in amplitude (power setting remainingunaltered). Lastly, the study did not show a statistically significant change in tidal volume withchanges in lung compliance. Future studies may be required to further evaluate the clinicalsignificance of the same. Conclusion:1. Many factors affect delivery of tidal volume during high frequency ventilation and thus it isnot constant. Choice of in-line suction system to be placed in line is one of the determinants ofthe same.2. Lung compliance changes lead to associated changes in amplitude delivery by HFOV. Thisshould be adjusted as patient condition improves by altering the power settings to ensure optimalventilation and to avoid trauma to the lungs.

Title: Physiological response of competitors Fireball dinghy class in the model sailing race. Objectives: The main intention of the thesis is to detect the physical demands (difficulties) of sailing boat race categorized as Fireball double crew. The variables of physiological response to the load of competitors recorded are being measured using simulated race under laboratory conditions. At that point, this opportunity enabled us to carry out further comparisons and examine the physical demands of individual post at various directions of wind. Methods: The entire investigation of detecting physiological functions of competitors will be carried out noninvasively throughout the simulation of sailing using metabolic analyser tool and sport tester. From the feedback, we will obtained figures and originate the physiological response of human body to the load. Due to the investigation is being implemented on the double crew boat Fireball; both competitors (crew/helmsman) performing different tasks will be simulated and examined individually. Simulated race will last 24 minutes and competitors will have to face different wind courses, precisely cruising upwind, crosswind and tailwind. Results: From the measured results, we can state that most of the time during simulated race, the performance of racers...

Introdução: A tomografia de impedância elétrica (TIE) é uma técnica de imagem não invasiva que mensura o potencial elétrico na superfície torácica através de eletrodos colocados ao redor do tórax. Essas medidas são transformadas em uma imagem bidimensional da distribuição da impedância elétrica no tórax. Esse instrumento detecta modificações da densidade pulmonar e distribuição do volume corrente. Entretanto, é necessário melhor avaliação da sua eficiência em estimar o volume corrente (VT) a cada ciclo ventilatório. O objetivo do estudo é avaliar a correlação do volume estimado pela TIE com o VT aplicado durante o suporte ventilatório mecânico. Métodos: Inicialmente, foram estudados cinco suínos da raça Landrace. Os animais foram sedados, intubados e monitorados com a TIE. Foram aplicados volumes incrementais (100, 250, 500, 750 e 1000 mL) com a seringa de precisão em ZEEP e com PEEP de 5, 10 e 20 cmH2O, antes e depois da promoção de lesão pulmonar com lavagem com solução salina. Posteriormente, outros cinco animais foram monitorados com a tomografia computadorizada de tórax por raios X (TC) e a TIE. Foram aplicados volumes incrementais (250, 500 e 1000 mL) com a seringa de precisão em ZEEP e com PEEP de 10 e 20 cmH2O, também antes e depois da promoção de lesão pulmonar. A amplitude da variação de impedância mensurada pela TIE foi convertida em volume e foi calculado o volume de ar na TC. Análises de correlação e concordância foram realizadas com o programa \"R\" (© R Foundation for Statistical Computing). Resultados: Em ZEEP, o coeficiente de correlação entre os volumes estimado pela TIE e calculado pela TC foram, respectivamente, 0,90 e 0,96 na comparação com a seringa de precisão. O coeficiente de determinação entre a TIE e a seringa de precisão foi progressivamente reduzindo (0,90; 0,89 e 0,81 com PEEP de 5; 10 e 20, respectivamente) com o aumento do volume pulmonar promovido pela elevação da PEEP. A TC mostrou um deslocamento progressivo do conteúdo aéreo no sentido caudal com o aumento do volume pulmonar. Conclusões: Há uma boa correlação entre o volume estimado pela TIE e o VT aplicado durante o suporte ventilatório mecânico quando utilizados volumes e pressões usuais na prática clínica / Rationale: Electrical impedance tomography (EIT) is a noninvasive imaging tool that reconstructs a cross-sectional image of the lung\'s regional conductivity using electrodes placed circumferentially around the thorax. It is able to detect changes of lung air content and tidal volume (VT) distribution. However, better evaluation of its capacity to quantify VT variations is necessary. The aim of our study was to assess the correlation between volume estimated by EIT and tidal volume applied at different positive end-expiratory pressures (PEEP). Methods: Initially, in an experimental study five mechanically ventilated pigs monitored by EIT were studied. VT increments (100, 250, 500, 750 and 1000 mL) were applied with a calibrated syringe at zero end-expiratory pressure (ZEEP) and PEEP levels of 5, 10 and 20 cmH2O before and after lung-injury (induced by saline lavage). Another five pigs was monitored by EIT and x-ray computed tomography (CT). VT increments (250, 500 and 1000 mL) were applied with a calibrated syringe at zero end-expiratory pressure (ZEEP) and PEEP levels of 10 and 20 cmH2O before and after lung-injury. Lung air volume was calculated at CT scan and the amplitude of impedance change measured by EIT was converted to volume (mL). Correlation and agreement analysis was performed at \"R\" program (© R Foundation for Statistical Computing). Results: At ZEEP, volume estimated by EIT and volume calculated at CT obtained r2 = 0.90 and 0.96 respectively, when compared to calibrated syringe. The coefficient of correlation between EIT and calibrated syringe impaired (0.90; 0.89 and 0.81 with PEEP of 5; 10 and 20, respectively) with increase of the lung volume due to increased PEEP. CT showed a progressive displacement of the air content to the caudal thoracic levels with the increase of the lung volume. Conclusion: EIT is able to estimate tidal volume during mechanical ventilatory support when used volumes and pressures usually applied at bedside