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Psychophysiological Effects of Respiratory Challenges before and after Breathing Training in Panic Disorder and Patients suffering from Episodic Anxiety AttacksWollburg, Eileen 04 December 2007 (has links)
Panic Disorder (PD) has been associated with abnormalities in the respiratory system for a long time, and treatment programs aimed at reversing these abnormalities have been developed. Panicogenic effects of biological challenges have been shown to be altered after successful treatment. Furthermore, there is evidence that anxious non-PD patients show similar responses to these challenges and hence may benefit from some kind of breathing training (BT). To test these assumptions, we recruited 45 PD patients, 39 Episodic Anxiety (EA) patients who suffered from subclinical panic attacks, and 20 non-anxious controls (NAC). Patients were randomized to one of two versions of a 4-week therapy with BT, either lower or raise end-tidal pCO2, or a waiting list (WL). Before and after treatment, participants underwent in randomized order a Voluntary Hypoventilation (VHO) test and a Voluntary Hyperventilation (VHT) test in which they were asked to either lower or raise their pCO2 while psychophysiological measures were recorded. Each test consisted of 3 segments: 1 min baseline, 3 min paced breathing, and 8 min recovery. Before treatment, PD and EA patients were more anxious, distressed, tense, and worried than NAC, and felt more dizziness, chest pain, and nausea during the laboratory assessment. However, increases in psychological symptoms or physiological sensations from baseline to the paced breathing segments were not different between groups. The two tests produced similar changes except that anxiety and dizziness increased more during the VHT than VHO. We replicated baseline breathing abnormalities previously reported for PD patients, namely greater respiration rate, tidal volume instability, and number of sighs. However, analyses did not find that patients recovered slower to either challenge. After treatment, both therapies improved on the main outcome measure. Furthermore, BT affected baseline pCO2, resulting in lower levels in the hypocapnic groups and higher levels in the hypercapnic groups without affecting any other measures. We conclude that baseline respiratory abnormalities are specific to PD. However, data suggest that the manipulations might have been too weak to elicit other previously reported group differences. Breathing training was equally effective for the lower and raise BT. Hence, factors unrelated to modifying one’s pCO2 must have accounted for the symptomatic improvement. Breathing training should not be restricted to PD but be applied to all patients suffering from anxiety attacks.
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Optimizing and evaluation of a methacholine provocation test : with application in occupational researchSundblad, Britt-Marie January 2002 (has links)
<p>We have developed a methacholine provocation method, which detects bronchial responsiveness in more than 80% of healthy subjects. The method enables us to detect differences in bronchial responsiveness within the normal range. </p><p>With this method FEV1 and Gaw had similar sensitivity in detecting small differences in bronchial responsiveness. Differences, between protocols when using doubling or fourfold concentration steps emphasize the importance to strictly adhere to a predefined protocol. </p><p>Deep inhalation associated with the FEV1 manoeuvre decreases bronchial tone induced by methacholine for up to 6 minutes, which emphasizes the importance of exact timing between successive FEV1 measurements in bronchial provocation tests. There is a substantial overlap in bronchial responsiveness between healthy and asthmatic subjects and a deep inhalation at the end of the methacholine test challenge could not discriminate between asthmatic and non-asthmatic subjects.</p><p>Inhalation of dust in a swine confinement building causes an intense airway inflammatory reaction with an extensive migration of inflammatory cells, predominantly neutrophils, into the upper and lower airways. Bronchial responsiveness to methacholine increased by about 3 doubling concentration steps and was normalized one week after exposure. However, exposure to dust in a swine confinement building did not yield increased bronchial responsiveness to eucapnic hyperventilation with dry air which is often observed in asthmatic subjects. Exhaled NO was approximately doubled five hours after exposure and in the present study we found no relationship between exhaled NO levels and bronchial responsiveness in healthy subjects. </p><p>Protection with half-mask inhibited the dust induced increase of exhaled NO whereas the increase in bronchial responsiveness was influenced only to a minor extent.</p><p>These findings, do not support the hypothesis that the increased bronchial responsiveness following organic dust exposure is directly caused by the inflammation. Instead, a possible direct effect on the smooth muscle and swelling of the airway mucosa and increased secretions due to the general inflammatory reaction probably leads to airway narrowing enhancing the post-exposure bronchial response to methacholine. </p>
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Optimizing and evaluation of a methacholine provocation test : with application in occupational researchSundblad, Britt-Marie January 2002 (has links)
We have developed a methacholine provocation method, which detects bronchial responsiveness in more than 80% of healthy subjects. The method enables us to detect differences in bronchial responsiveness within the normal range. With this method FEV1 and Gaw had similar sensitivity in detecting small differences in bronchial responsiveness. Differences, between protocols when using doubling or fourfold concentration steps emphasize the importance to strictly adhere to a predefined protocol. Deep inhalation associated with the FEV1 manoeuvre decreases bronchial tone induced by methacholine for up to 6 minutes, which emphasizes the importance of exact timing between successive FEV1 measurements in bronchial provocation tests. There is a substantial overlap in bronchial responsiveness between healthy and asthmatic subjects and a deep inhalation at the end of the methacholine test challenge could not discriminate between asthmatic and non-asthmatic subjects. Inhalation of dust in a swine confinement building causes an intense airway inflammatory reaction with an extensive migration of inflammatory cells, predominantly neutrophils, into the upper and lower airways. Bronchial responsiveness to methacholine increased by about 3 doubling concentration steps and was normalized one week after exposure. However, exposure to dust in a swine confinement building did not yield increased bronchial responsiveness to eucapnic hyperventilation with dry air which is often observed in asthmatic subjects. Exhaled NO was approximately doubled five hours after exposure and in the present study we found no relationship between exhaled NO levels and bronchial responsiveness in healthy subjects. Protection with half-mask inhibited the dust induced increase of exhaled NO whereas the increase in bronchial responsiveness was influenced only to a minor extent. These findings, do not support the hypothesis that the increased bronchial responsiveness following organic dust exposure is directly caused by the inflammation. Instead, a possible direct effect on the smooth muscle and swelling of the airway mucosa and increased secretions due to the general inflammatory reaction probably leads to airway narrowing enhancing the post-exposure bronchial response to methacholine.
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Repercussão da manobra de hiperventilação breve sobre a hemodinâmica cerebral, sistêmica e alterações gasométricas em pacientes sob assistência ventilatória mecânica / Repercussion of Brief Hyperventilation Manuever on the Cerebral and Systemic Hemodynamic and Gasometric Parameters in Mechanically Ventilated PatientsCerqueira, Telma Cristina Fontes 04 March 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Measurements of respiratory mechanics, very important to conduct the patient with mechanical ventilation, are obtained with the relaxation of respiratory muscle in sedated or paralyzed patients or through a brief period of hyperventilation
(HV), which is possible to decrease the drive ventilation of patient. However, it´s known that the hyperventilation decreases the carbon dioxide arterial pressure (PaCO2) and can induce changes in the cerebral blood flow. Then, this study proposes to verify the effects of this brief period of HV on the gasometric parameters, cerebral and systemic hemodynamic in 15 mechanically ventilated patients, with
ventilation drive and different pathologies, except cerebral pathology, admitted in Intensive Care Unit of Vita Hospital in Curitiba-PR; being 12 males (80%) and three females (20%), mean age of 61,29 (± 18,97), eight clinical and seven surgical
diagnosis. The protocol consisted of a brief HV with increase by 50% from previous minute volume of patient for two minutes. The variables were recorded before, on the
first minute of HV (HV1), on the second minute (HV2) and five minutes after the end of maneuver. The parameters recorded were mean blood flow velocity and pulsatility index through transcranial doppler of the middle cerebral arteries, blood gas
parameters (pH, PaCO2, EtCO2, HCO3, BE, PaO2, SatO2 e SpO2), besides heart rate and mean arterial pressure. The data were averaged statistically by ANOVA, Newman-Keuls and Wilcoxon tests. The normality condition of data were averaged by Kolmogorov-Smirnov. Values of p<0,05, indicate statistically significant. The results show a decrease of mean blood flow velocity of the right (p=0,18888) and left
(p=0,0071) middle cerebral arteries, mainly on the first minute of HV, estimating a decrease of cerebral blood flow (4,12% e 6,51%, of the right and left middle cerebral arteries, bespectively). Five minutes after HV, there was a return to baseline values. In relation to gasometric parameters, there were a significant variation of EtCO2 and PaCO2 during the HV, with smaller changes of PaCO2 in relation to EtCO2. The
pulsatility index, another gasometric parameters, heart rate and mean arterial pressure remained stable during HV. Concluding, based on results of this study, that the maneuver of HV may be security applied and does not promote cerebral and systemic repercussion in studied patients. / Cálculos da mecânica respiratória, tão importantes para a condução do paciente sob ventilação mecânica (VM), são obtidos com o relaxamento da musculatura respiratória através de sedação, curarização ou breve período de
hiperventilação (HV), em que é possível diminuir o drive ventilatório do paciente. Porém, sabe-se que a HV reduz a pressão arterial de dióxido de carbono (PaCO2) e pode levar a alterações do fluxo sanguíneo cerebral (FSC). Com isso, este trabalho se propôs a verificar os efeitos deste breve período de HV na hemodinâmica cerebral, sistêmica e variáveis gasométricas em 15 pacientes sob VM apresentando
drive ventilatório, com patologias diversas, exceto patologias cerebrais, internados na Unidade de Terapia Intensiva do Hospital Vita na cidade de Curitiba-PR; sendo 12 pacientes do sexo masculino (80%) e três do sexo feminino (20%), com média de idade de 61,29 (±18,97), sendo oito diagnósticos cirúrgicos e sete clínicos. O protocolo consistia de uma HV breve com aumento de 50% do volume minuto prévio do paciente por dois minutos. A coleta dos dados foi feita antes, no primeiro minuto de HV (HV1), no segundo minuto (HV2) e cinco minutos após o final da manobra. Foram colhidos dados de Velocidade Média (Vm) do FSC e Índice de Pulsatilidade
(IP) ao Doppler Transcraniano (DTC) das artérias cerebrais médias (ACMs), dados gasométricos (pH, PaCO2, EtCO2, HCO3, BE, PaO2, SatO2 e SpO2), bem como freqüência cardíaca (FC) e pressão arterial média (PAM). Os dados foram avaliados estatisticamente pelos testes ANOVA, Newman-Keuls e teste não-paramétrico de Wilcoxon. A condição de normalidade dos dados foi avaliada pelo teste de
Kolmogorov-Smirnov. Valores de p<0,05 indicaram significância estatística. Como resultados, observou-se que houve uma diminuição da velocidade média (Vm) do
FSC das ACMs direita (p=0,18888) e esquerda (p=0,0071), mais evidente no primeiro minuto de HV, estimando uma diminuição do FSC (4,12% e 6,51%, nas ACMs direita e esquerda, respectivamente). Após 5 minutos do final da manobra, encontrou-se retorno da Vm e do FSC aos valores iniciais. Quanto às variáveis gasométricas observou-se que o EtCO2 e PaCO2 alteram com a manobra de HV breve, porém com menores mudanças da PaCO2 em relação à EtCO2. O IP, as demais variáveis gasométricas, a FC e a PAM permaneceram estáveis durante a HV. Conclui-se, portanto, a partir dos dados obtidos neste estudo, que a manobra de
HV pode ser realizada de forma segura, sem repercussão hemodinâmica cerebral e sistêmica dos pacientes estudados.
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Repercussão da manobra de hiperventilação breve sobre a hemodinâmica cerebral, sistêmica e alterações gasométricas em pacientes sob assistência ventilatória mecânica / Repercussion of Brief Hyperventilation Manuever on the Cerebral and Systemic Hemodynamic and Gasometric Parameters in Mechanically Ventilated PatientsCerqueira, Telma Cristina Fontes 04 March 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Measurements of respiratory mechanics, very important to conduct the patient with mechanical ventilation, are obtained with the relaxation of respiratory muscle in sedated or paralyzed patients or through a brief period of hyperventilation
(HV), which is possible to decrease the drive ventilation of patient. However, it´s known that the hyperventilation decreases the carbon dioxide arterial pressure (PaCO2) and can induce changes in the cerebral blood flow. Then, this study proposes to verify the effects of this brief period of HV on the gasometric parameters, cerebral and systemic hemodynamic in 15 mechanically ventilated patients, with
ventilation drive and different pathologies, except cerebral pathology, admitted in Intensive Care Unit of Vita Hospital in Curitiba-PR; being 12 males (80%) and three females (20%), mean age of 61,29 (± 18,97), eight clinical and seven surgical
diagnosis. The protocol consisted of a brief HV with increase by 50% from previous minute volume of patient for two minutes. The variables were recorded before, on the
first minute of HV (HV1), on the second minute (HV2) and five minutes after the end of maneuver. The parameters recorded were mean blood flow velocity and pulsatility index through transcranial doppler of the middle cerebral arteries, blood gas
parameters (pH, PaCO2, EtCO2, HCO3, BE, PaO2, SatO2 e SpO2), besides heart rate and mean arterial pressure. The data were averaged statistically by ANOVA, Newman-Keuls and Wilcoxon tests. The normality condition of data were averaged by Kolmogorov-Smirnov. Values of p<0,05, indicate statistically significant. The results show a decrease of mean blood flow velocity of the right (p=0,18888) and left
(p=0,0071) middle cerebral arteries, mainly on the first minute of HV, estimating a decrease of cerebral blood flow (4,12% e 6,51%, of the right and left middle cerebral arteries, bespectively). Five minutes after HV, there was a return to baseline values. In relation to gasometric parameters, there were a significant variation of EtCO2 and PaCO2 during the HV, with smaller changes of PaCO2 in relation to EtCO2. The
pulsatility index, another gasometric parameters, heart rate and mean arterial pressure remained stable during HV. Concluding, based on results of this study, that the maneuver of HV may be security applied and does not promote cerebral and systemic repercussion in studied patients. / Cálculos da mecânica respiratória, tão importantes para a condução do paciente sob ventilação mecânica (VM), são obtidos com o relaxamento da musculatura respiratória através de sedação, curarização ou breve período de
hiperventilação (HV), em que é possível diminuir o drive ventilatório do paciente. Porém, sabe-se que a HV reduz a pressão arterial de dióxido de carbono (PaCO2) e pode levar a alterações do fluxo sanguíneo cerebral (FSC). Com isso, este trabalho se propôs a verificar os efeitos deste breve período de HV na hemodinâmica cerebral, sistêmica e variáveis gasométricas em 15 pacientes sob VM apresentando
drive ventilatório, com patologias diversas, exceto patologias cerebrais, internados na Unidade de Terapia Intensiva do Hospital Vita na cidade de Curitiba-PR; sendo 12 pacientes do sexo masculino (80%) e três do sexo feminino (20%), com média de idade de 61,29 (±18,97), sendo oito diagnósticos cirúrgicos e sete clínicos. O protocolo consistia de uma HV breve com aumento de 50% do volume minuto prévio do paciente por dois minutos. A coleta dos dados foi feita antes, no primeiro minuto de HV (HV1), no segundo minuto (HV2) e cinco minutos após o final da manobra. Foram colhidos dados de Velocidade Média (Vm) do FSC e Índice de Pulsatilidade
(IP) ao Doppler Transcraniano (DTC) das artérias cerebrais médias (ACMs), dados gasométricos (pH, PaCO2, EtCO2, HCO3, BE, PaO2, SatO2 e SpO2), bem como freqüência cardíaca (FC) e pressão arterial média (PAM). Os dados foram avaliados estatisticamente pelos testes ANOVA, Newman-Keuls e teste não-paramétrico de Wilcoxon. A condição de normalidade dos dados foi avaliada pelo teste de
Kolmogorov-Smirnov. Valores de p<0,05 indicaram significância estatística. Como resultados, observou-se que houve uma diminuição da velocidade média (Vm) do
FSC das ACMs direita (p=0,18888) e esquerda (p=0,0071), mais evidente no primeiro minuto de HV, estimando uma diminuição do FSC (4,12% e 6,51%, nas ACMs direita e esquerda, respectivamente). Após 5 minutos do final da manobra, encontrou-se retorno da Vm e do FSC aos valores iniciais. Quanto às variáveis gasométricas observou-se que o EtCO2 e PaCO2 alteram com a manobra de HV breve, porém com menores mudanças da PaCO2 em relação à EtCO2. O IP, as demais variáveis gasométricas, a FC e a PAM permaneceram estáveis durante a HV. Conclui-se, portanto, a partir dos dados obtidos neste estudo, que a manobra de
HV pode ser realizada de forma segura, sem repercussão hemodinâmica cerebral e sistêmica dos pacientes estudados.
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Differenzierung von „pulmonal-vaskulärer Hyperventilation bei PAH/CTEPH“ und „Nicht pulmonal-vaskulärer Hyperventilation“ mittels Blutgasanalyse und Spiroergometrie / Discrimination of "pulmonary-vascular hyperventilation by PAH/CTEPH" and "Not pulmonary-vascular hyperventilation" using blood gas analyses and cardiopulmonary exercise testingKnobling, Franziska January 2022 (has links) (PDF)
Unklare Dyspnoe ist einer der Hauptvorstellungsgründe in den zentralen Notaufnahmen und pneumologischen Facharztpraxen [4]. Viele dieser Patienten hyperventilieren. Die Hyperventilation ist jedoch ein sehr unspezifisches Merkmal und kommt sowohl bei Pa- tienten mit Lungenerkrankungen, aber auch bei denen ohne Vorerkrankungen an der Lunge, sogar bei Patienten mit psychischen Störungen vor.
Die PH ist weit verbreitet [1], wird spät erkannt [130, 160], geht ebenfalls mit einer Hy- perventilation einher und die Inzidenz der CTEPH scheint höher als bisher angenommen [1]. Goldstandard für die Diagnosestellung der PH ist der Rechtsherzkatheter [12]. Aller- dings wurde bereits vor 20 Jahren propagiert, dass mittels einer Spiroergometrie bei PH wegweisende Daten erhoben werden können und dies die Anzahl der notwendigen Rechtsherzkatheter reduzieren und im Gegenzug die Durchführung von Spiroergomet- rien steigern könnte [242, 243], um möglichst früh Patienten mit pulmonal-vaskulärer Hyperventilation von denen mit „Nicht pulmonal-vaskulärer Hyperventilation“ zu unter- scheiden.
In dieser Arbeit wurden die Daten von Pateinten mit Hyperventilation analysiert (64 PAH, 46 CTEPH, 64 „Nicht pulmonal-vaskuläre Hyperventilation“) und bezüglich BGA und Spi- roergometrie ausgewertet.
Anhand der BGA in Ruhe konnten keine signifikanten Unterschiede zwischen den Grup- pen festgestellt werden. Während sich auch der kapillär gemessene pCO2Spiegel unter submaximaler Belastung bei vaskulär-assoziierter Bedarfshyperventilation und „Nicht pulmonal-vaskulärer Hyperventilation“ nicht signifikant unterschieden, zeigten die spiro- ergometrischen Parameter alle einen signifikanten Unterschied. Die höchste Sensitivität (83,6 %) und den besten negativ prädiktiven Wert (70,5 %) bei Betrachtung des Gesamt- kollektivs erreichte der Parameter VE/VCO2-slope, die beste Spezifität (82,8 %) und den höchsten positiven Vorhersagewert (88,5 %) war bei Aa-DO2 zu sehen.
Auch der, während der Maximalbelastung in der Spiroergometrie gemessene pO2-Spie- gel unterschied sich in den Gruppen signifikant voneinander.
Durch die Kombination mehrerer Parameter (VE/VCO2-slope, PETCO2 AT, Aa-DO2, P(a- ET)CO2 sowie pO2-Spiegel bei Maximalbelastung) kann eine Sensitivität von 82,7 % und
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5 Zusammenfassung
ein positiver Vorhersagewert von 89,2 % zur Erkennung der Patienten mit „Hyperventi- lation bei PAH/CTEPH“ erreicht werden. Die Spezifität liegt bei 82,3 % und der negativ prädiktive Wert bei 72,9 %.
Zusammenfassend lässt sich sagen, dass die Spiroergometrie mit kombinierter BGA eine geeignete Methode ist, Patienten mit vaskulär-assoziierter Hyperventilation zu er- kennen bzw. nicht-invasiv die Prätest-Wahrscheinlichkeit für weitere Untersuchungen zu erhöhen. / Unclear dyspnea is one of the most common reasons for presenting in an emergency room or at a pulmonologist’s office. Many patients with unclear dyspnea hyperventilate. However, hyperventilation is a very unspecific characteristic of pulmonary disease that can also be found in patients without pre-existing pulmonary illness and even in patients with mental illness.
Pulmonary hypertension (PH) is widespread, diagnosed late and presents also with hyperventilation. The incidence of chronic thromboembolic pulmonary hypertension (CTEPH) appears to be higher than previously reported. Right heart catheterization is used as the gold standard for diagnosing PH. However, for already 20 years it has been suggested that cardiopulmonary exercise testing (CPET) can deliver informative results to differentiate patients with pulmonary-vascular hyperventilation from patients with “not pulmonary-vascular hyperventilation” early, so that the number of right heart catheterizations can be reduced.
Here, we analyzed the data of blood gas analyses and cardiopulmonary exercise testing of patients who hyperventilate (64 with pulmonary arterial hypertension (PAH), 46 with CTEPH, and 64 with “not pulmonary-vascular hyperventilation”).
All parameters from the CPET resulted in significant differences between the groups. The best sensitivity (83.6 %) and the best negative predictive value (70.5 %) were achieved in the VE/VCO2-slope. Aa-DO2 was the parameter with the highest specificity (82.8 %) and positive predictive value (88.5 %).
Also, there was a significant difference between the groups in the pO2-level at maximum load during CPET.
A combination of certain parameters (VE/VCO2, PETCO2 AT, Aa-DO2, P(a-ET)CO2 and pO2-level at maximum load) could achieve a sensitivity of 82,7 % and a positive predictive value of 89.2 % to detect patients with “hyperventilation by PAH/CTEPH”. Here, the specificity was 82.3 % and the negative predictive value was 72.9 %.
In summary, the combination of CPET and blood gas analyses is an appropriate method to detect patients with pulmonary-vascular hyperventilation or at least to non-invasively increase the pretest probability for follow-up examinations.
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Hyperventilation and ECG components used in exercise for diagnosis of ischemic heart disease in healthy femalesRose, Timothy M. 12 September 2009 (has links)
Hyperventilation has been reported to cause false-positive ischemic shifts in the ST-segment of the electrocardiogram during exercise. These responses have been observed to occur at a higher incidence in females than males. Therefore, the purpose of this study was to determine the effects of the performance of pretest hyperventilation on ECG components that are suggestive of myocardial ischemia in females. A standard 12-lead Mason-Likar recording set was used including leads I, II, II, aVR, aVL, aVF, V₂, and V₅. Fifteen females comprised the subject pool for this study, which was screened on the basis of J-point depression in a preliminary exercise procedure. The fifteen subjects each performed two exercise sessions, one with no hyperventilation and the other with a preliminary hyperventilation. Statistically significant differences were found between the baseline and post-hyperventilation ECG (P<.05). Analysis of the results revealed no significant differences in J-junction depression, ST slope, and the ST integral between the two testing conditions. Hyperventilation did affect the ST responses of the ECG in these young adult females at baseline and its continued use in conjunction with graded exercise testing may help uncover ST-segment changes associated with false-positive exercise responses. Hyperventilation may be performed in young adult females in conjunction with GXTs without the liklihood of augmenting ST-segment shifts during the exercise. / Master of Science
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Avaliação do broncoespasmo induzidos por exercício em riníticos não asmáticosRODRIGUES FILHO, Edil de Albuquerque 29 February 2016 (has links)
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Previous issue date: 2016-02-29 / CAPEs / As queixas respiratórias após exercício físico são comuns em riniticos, asmáticos e em indivíduos sem estas doenças. Uma das causa é o broncoespasmo induzido pelo exercício (BIE), definido como o estreitamento dos brônquios após exercício físico vigoroso. Estes sintomas podem limitar as atividades destes adolescentes e acarretar em consequências negativas nas atividades diárias e na qualidade de vida. O objetivo principal desse estudo foi avaliar a prevalência do BIE em riníticos não asmáticos e comparar as respostas no volume expiratório forçado no 1º segundo (VEF1) aos testes de Hiperventilação Eucápnica Voluntária (HEV) e Corrida em esteira (CE). Métodos: Foi realizado um estudo descritivo, analítico, inferencial, transversal, para avaliação de prevalência, com amostras por conveniência de indivíduos dos 10 aos 20 anos de idade, realizado no Serviço de Pneumologia do Hospital das Clínicas - UFPE. Foram mensuradas variáveis antropométricas (peso e estatura), e aplicados questionários para avaliação da gravidade da rinite, asma no passado e de queixas respiratórias aos exercícios. O VEF1 foi determinado em duplicata através da espirometria, antes e aos 3, 5, 7, 10, 15 e 30 minutos após cada teste diagnóstico. Para o teste da CE, os indivíduos realizaram o exercício por um período de oito a nove minutos, sendo que nos seis minutos finais deveria manter a frequência cardíaca alvo (estimada em 80% a 90% da FC máxima : 220- idade). Para a realização da HEV, os indivíduos realizaram uma manobra de hiperventilação durante seis minutos, respirando ar seco adicionado de 5% de CO2, com uma ventilação minuto alvo de 21 vezes o seu VEF1 basal. O BIE foi diagnosticado quando houve uma redução > 10% do valor basal detectado em dois momentos consecutivos após a provocação. Resultados: Foram estudados 35 indivíduos testados com média da idade de 16,3 + 3,6 anos. O BIE foi diagnosticado em 13 sujeitos (37%) por um dos dois métodos ou ambos. Em 9 indivíduos após a CE e em 10 após a HEV e em 6 por ambos, mostrando uma concordância moderada entre os métodos (Kappa = 0,489). O VEF1 basal expresso como percentual do predito foi maior naqueles indivíduos com testes negativos que nos positivos (101% e 85%, p<0,02 para a CE e 101% versus 85%, p< 0,001 para a HEV) e não foram verificadas diferenças na frequência cardíaca máxima alcançada entre os sujeitos com teste positivo e negativo na corrida em esteira e nem na ventilação atingida quando os pacientes foram submetidos à HEV. Conclusão: A prevalência do BIE em pacientes com rinite em nossa região é comparável àquelas descritas na literatura mais recente. Houve uma concordância moderada entre os testes empregados para o diagnóstico do BIE, o que indica cautela quando se pretende comparar os dois métodos ou mesmo considerar seus resultados de forma intercambiável. / Respiratory complaints after exercise are common in rhinitis, asthma, and in individuals without these diseases. One cause is exercise-induced bronchospasm (EIB), defined as the narrowing of the bronchi after strenuous exercise. These symptoms can limit the activities of these adolescents and result in negative consequences in daily activities and quality of life. The main objective was to evaluate the prevalence of EIB and compare the answers in FEV1 to eucapnic voluntary hyperventilation testing (EVH) and Treadmill running (TR) in rhinitis but non-asthmatic patients. Methods: We conducted a descriptive, analytical, inferential, cross-sectional study, to assess EIB prevalence with a convenience samples of 10 to 20 year- old patients, held at the Pulmonology Department of Hospital das Clínicas – UFPE – Recife/Brazil. Anthropometric variables were measured (height and weight), and questionnaires to evaluate the severity of rhinitis, past asthma history and respiratory complaints on exercise. Forced expiratory volume in 1 second (FEV1) was determined in duplicate before and at 3, 5, 7, 10, 15 and 30 minutes after each diagnostic test. For TR test, subjects performed the exercise for a period of eight to nine minutes, in the final six minutes should maintain the target heart rate (estimated at 80% to 90% of maximum heart rate: 220- age). To perform the EVH, individuals sustained a hyperventilation maneuver breathing dry air enriched with 5% CO2 for six minutes with minute ventilation target at 21 times their baseline FEV1. EIB was diagnosed when there was a reduction > 10% from baseline FEV1 value detected at two consecutive times after challenges. Results: Of the 35 included subjects the mean age was 16.3 + 3,6 years. EIB was diagnosed in 13 patients (37%) by one of the two methods or both. In nine individuals after TR and 10 after EVH and in 6 by both methods, showing a moderate agreement between the methods (Kappa = 0.489). Baseline FEV1 expressed as a percentage of predicted was higher in those with negative tests com testes negativos (101% and 85%, p<0,02 for TR and 101% versus 85%, p< 0,001 for EVH) but no differences were observed in maximum heart rate achieved among patients with positive and negative treadmill tests nor the ventilation achieved when patients underwent EVH. Conclusion: The prevalence of EIB in patients with rhinitis in our region is comparable to those described in the most recent literature. There was a moderate agreement between the tests, which suggests that we have to be cautious when trying to compare them or when considering its results interchangeably.
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Effets ventilatoire et cardiaque de l'hyperventilation volontaire. Etude chez les volontaires sains et les patients souffrant du trouble paniqueBesleaga, Tudor 19 October 2011 (has links) (PDF)
L'objectif du travail était l'étude des effets ventilatoires et cardiovasculaires de l'hyperventilation volontaire (HV) ainsi que psychophysiologiques chez les sujets sains et les patients souffrant de trouble panique. Nous avons mené deux études : la première sur des sujets sains sur lesquels le débit ventilatoire, les mouvements du thorax et de l'abdomen, le pourcentage de CO2 dans l'air expiré (FETCO2), l'électrocardiogramme (ECG) ont été enregistre au cours de deux tests d'hyperventilation : l'un à la fréquence de repos (THV) et l'autre à la fréquence de 20 cycles par minute (THV20). La deuxième étude a porté sur un groupe de sujets sains (groupe contrôle) et un groupe de patients souffrant du trouble panique (TP) sur lesquels le débit ventilatoire et l'ECG ont été enregistrés et les niveaux d'anxiété (Spielbergher), de dépression (Beck), du stress (Holmes), des symptômes de troubles fonctionnels (Profil Végétatif) et des symptômes produits par l'hyperventilation ont été évalués. Les variables ventilatoires classiques ont été calculées cycle par cycle. La forme des cycles ventilatoires a été étudiée en calculant les asters (représentation vectorielle des quatre premières harmoniques d'une décomposition en série de Fourier de chaque cycle respiratoire) ainsi que les triads (complexe trivarié: volume courant Vt, temps d'inspiration Ti et d'expiration Te). Les asters et triads ont été comparés dans les différentes conditions en utilisant un test statistique multi-varié (test de similarité). Les composantes du spectre de la période cardiaque, les périodes cardiaques moyennes et les coefficients de variation de la période cardiaque ont été calculés à partir des intervalles RR de l'ECG. Les résultats du test de similarité montrent que la forme du cycle ventilatoire de repos est modifiée au cours de l'hyperventilation volontaire, mais que la forme cycle à l'HV est conservée à un an d'intervalle et aussi pour les périodes d'HV des deux tests THV et TVH20. L'hyperventilation volontaire modifie significativement les caractéristiques de la ventilation (variables et forme du cycle). Cependant, au cours de l'hyperventilation volontaire ces caractéristiques sont conservées à un an d'intervalle et il semble que la personnalité ventilatoire de repos ne se conserve pas au cours de l'HV, mais l'on retrouve une personnalité " différente " au cours de l'HV. Les variables ventilatoires et leurs coefficients de variation sont modifiés pendant toutes les périodes des deux tests d'hyperventilation. Les variables ventilatoires du groupe contrôle ne sont significativement différentes du groupe TP qu'au cours des trois premières minutes de récupération. La variabilité cardiaque est significativement modifiée au cours des périodes des tests d'hyperventilation volontaire. La variabilité cardiaque est significativement plus faible chez les patients TP que chez les sujets sains et l'analyse des composantes spectrales de la période cardiaque permet de déduire que les patients semblent présenter au repos et pendant l'HV, une activité cardio-vagale plus faible et une activité sympathique plus élevée que les sujets sains. Les patients TP ont des niveaux plus élevés d'anxiété et de dépression que les sujets du groupe contrôle. Au cours des trois première minutes de récupération après l'hyperventilation volontaire à la fréquence de repos, la ventilation est plus élevée chez les sujets présentant une anxiété élevée que chez ceux présentant une anxiété normale à moyenne. Le nombre de symptômes fonctionnels et produits par l'hyperventilation volontaire est aussi plus élevé chez les sujets présentant une anxiété élevée.
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Respostas cardiorrespiratórias do teleósteo de respiração aérea, Clarias gariepinus, exposto à hipóxia gradualBelão, Thiago de Campos 25 June 2010 (has links)
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Previous issue date: 2010-06-25 / Financiadora de Estudos e Projetos / Air-breathing fish are classified as obligatory (when breathing obligatory atmospheric air independently of the water O2 tension) or facultative air-breather (using an air breathing organ ABO -, when theirs gills are not able to extract all O2 necessary to maintain the aerobic mechanisms under hypoxic conditions). The catfish, Clarias gariepinus, is airbreathing fish that shows modifications on the gill lamella, forming a ventilatory fan, and on the 2o e 4o gill arches, forming an arborescent organ. These structures form the ABO of this specie.The objectives of the present study were: 1. To determine if C. gariepinus is an obligatory or a facultative air breather. 2. To analyze the cardio-respiratory responses ( VO2 - metabolic rate; VG - gill ventilation; VT ventilatory volume; fR respiratory frequency; EO2 O2 extraction from the ventilatory current; fH- heart frequency) in response to progressive hypoxia. 3. To verify if the critical O2 tension (PcO2) of this specie is correlated with the O2 uptake from the atmospheric air.To classify the air-breathing mode of C. Gariepinus, the fish (Wt ~ 350 g; n = 7) were maintained in normoxia during 24 hours without access to air. The fR maintained constant during all the experiment and there was no mortality, indicating that C. gariepinus is a facultative air-breather. To analyze the cardio-respiratory responses to progressive hypoxia, VO2 , EO2, fR, VT, VG , EO2 and fH were recorded under the following water O2 tensions(PwO2): 100, 70, 50 e 30 mmHg. Fish maintained a constant VO2 until the PcO2 (~ 55 mmHg), below which VO2 decreased significantly. This decreasing was followed with the significant reduction of EO2 in PinspO2 of 62,7 ± 1,30 mmHg reaching values of 19,6 ± 1,9 % in severe hypoxia. The VG and the VT increased progressively until PinspO2 of 28,0 ± 0,5 mmHg, reaching highest values of, respectively, 1545,7 ± 63,5 mLH2O.kg-1.min-1, 33,9 ± 0,8 mLH2O.Kg-1.resp-1 e 57,2 ± 1,4 resp.min-1. The fH reduced progressively from 43,4 ± 0,4 bpm, in normóxia, arriving significant values just above the PcO2 and reaching minimum values (19,2 ± 3,0 bpm) in severe hypoxia. Under progressive hypoxia (100, 70, 50, 30 e 20 mmHg) and with the access to the atmospheric air, C. gariepinus (Wt ~ 610 g; n = 9) presented a 5-fold increase in the air-breathing frequency (fRA). A bradycardia was observed just before the air breath and a tachycardia just after.Concluding, C. gariepinus is a continuous facultative air-breathing fish that regulate the 2 O V until the PcO2 of ~54 mmHg. Below this tension fish increase the VG mainly due to a larger increase of VT (lower metabolic cost of VG ). The hypoxic pre-air breath bradycardia is characteristic of aquatic breathers while the post-air breath tachycardia is typical of air respirators. The fRA increased proportionally with the progressive hypoxia, mainly just above the PcO2. These results show that C. gariepinus is adapted to survive at hypoxic habitats and that this species show a higher dependence of the atmospheric air than the others facultative air-breathing fishes. / Peixes de respiração aérea são classificados como respiradores aéreos obrigatórios (aqueles que respiram ar atmosférico independente das tensões de O2 da água) ou facultativos (aqueles que usam o órgão de respiração aérea ABO quando as brânquias não conseguem extrair a quantidade de O2 necessário para manter o metabolismo aeróbico em condições hipóxicas). O bagre-africano, Clarias gariepinus, é um peixe de respiração aérea que apresenta modificações na lamela branquial, formando um leque ventilatório, e, nos 2os e 4os arcos branquiais, os órgãos arborescentes. Estas últimas estruturas formam o ABO desta espécie.Os objetivos do presente estudo foram: 1. Determinar se C. gariepinus é um respirador aéreo facultativo ou obrigatório. 2. Analisar as respostas cardiorrespiratórias ( VO2 - taxa metabólica; EO2 - extração de O2 da corrente ventilatória; VG - ventilação branquial; VT - volume ventilatório; fR - frequência respiratória; fH- frequência cardíaca) em resposta a hipóxia gradual. 3. Verificar se a tensão crítica de O2 (PcO2) desta espécie está relacionada com a tomada de O2 do ar atmosférico.Para classificar a modalidade da respiração aérea de C. gariepinus, os peixes (Wt ~ 350 g; n = 7) foram mantidos em normóxia durante 24 h sem acesso ao ar atmosférico. A fR manteve-se constante durante todo o experimento e não houve mortalidade, indicando que C. gariepinus é um respirador aéreo facultativo. Para analisar as respostas cardiorrespiratórias em normóxia (controle) e hipóxia gradual, a VO2 , EO2, fR, VT, V G e fH foram registradas durante as seguintes tensões de O2 (PwO2): 100, 70, 50 e 30 mmHg. Os peixes mantiveram VO2 constante até a PcO2 (~ 55 mmHg), abaixo da qual a VO2 decresceu significativamente. Esta diminuição da VO2 foi acompanhada da diminuição significativa da EO2 em PinspO2 de 62,7 ± 1,30 mmHg atingindo valores de 19,6 ± 1,9 %, em hipóxia severa. A VG , VT e fR aumentaram progressivamente até a PinspO2 de 28,0 ± 0,5 mmHg, chegando a valores máximos de, respectivamente, 1545,7 ± 63,5 mLH2O.kg-1.min-1, 33,9 ± 0,8 mLH2O.Kg-1.resp-1 e 57,2 ± 1,4 resp.min-1. A fH diminui progressivamente de 43,4 ± 0,4 bpm, em normóxia, até alcançar valores significativos próximos a PcO2 e valores mínimos em hipóxia severa (19,2 ± 3,0 bpm). Em experimentos de hipóxia gradual (100, 70, 50, 30, 20 e 10 mmHg) com acesso ao ar atmosférico, C. gariepinus aumentou aproximadamente 5x a frequência de respiração aérea (fRA). Em cada tensão hipóxica ocorreu uma bradicardia pré-RA seguido de taquicardia significativa pós-RA (típico de respiração aérea); a fR manteve-se praticamente constante (~ 32 resp.min-1) até as duas últimas PwO2 (20 e 10 mmHg), nas quais a fR diminuiu para 23,0 ± 1,18 resp.min-1.Finalmente, C. gariepinus é um peixe de respiração aérea facultativa contínua que regula a VO2 até a PcO2 de ~ 55 mmHg. Abaixo desta tensão o animal aumenta a VG devido principalmente a um pronunciado aumento na VT (diminuição do custo metabólico da VG ). A bradicardia hipóxica pré-RA é uma característica de respiradores aquáticos, enquanto a taquicardia hipóxica pós-RA é típica de respiradores aéreos. A fRA aumentou proporcionalmente com a hipóxia gradual, principalmente próximo a PcO2. Tais resultados demonstram que C. gariepinus está adaptado a sobreviver em habitats hipóxicos e demonstra uma maior dependência do ar atmosférico do que outros respiradores bimodais facultativos.
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