Thesis (M.D.)--University of Wisconsin, 1955. / Typewritten. Title from title screen (viewed July 3, 2008). Includes bibliographical references (p. [69]-73). Online version of the print original.

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No description available.

Thesis--Goteborgs Universitet.

Thesis--Goteborgs Universitet.

The present study was designed to investigate the hypothesis that individuals with the Hyperventilation Syndrome (HVS) are predominantly thoracic breathers. An analogue population was used to examine the breathing patterns of likely (N = 16) as opposed to unlikely (N = 16) hyperventilators. The relative thoracic as opposed to abdominal contribution to total respiratory volume was assessed during periods of quiet breathing and mild stress. Differences in thoracic contribution to total respiratory volume were not found between the likely and unlikely hyperventilators, nor between the quiet and mild stress conditions. A significant effect for sex existed, with females demonstrating a greater thoracic contribution to total respiratory volume than males. A significant group by sex interaction occurred, with likely male hyperventilators displaying a significantly lower thoracic contribution to total respiratory volume than both likely and unlikely females. Results are discussed in terms of application to the HVS, and future avenues of research are suggested.

No description available.

Thesis (M.S. Ed.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 68-72). Also available via the Internet.

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. / The aim of this research was the evaluation of the ventilatory and cardiovascular effects the voluntary hyperventilation (HV) and psychophysiological peculiarities in healthy subjects and patients with panic disorder. We performed two studies: we recorded the airflow, thoracic and abdominal movements, percent of the CO2 in expired air (FETCO2), electrocardiogram (ECG) in a group of healthy subjects during the two voluntary hyperventilation tests: at rest frequency (THV) and at 20 breaths per minute (THV20). The second study was performed on the healthy subjects (control group) and panic disorder patients (TP): airflow and ECG were recorded and the levels of anxiety (Spielbergher), depression (Beck), stress (Holmes), functional symptoms (Vegetative Profile) and symptoms generated by voluntary hyperventilation were evaluated. The classical respiratory variables were calculated cycle by cycle. The shape of ventylatory cycles were studied by calculation of asters (vectorial representation of the first four harmonics obtained by Fourier transformation of each respiratory cycle) and triads (trivariate complex tidal volume - Vt, inspiratory - Ti and expiratory - Te times). The asters and triads were compared in different conditions using statistical multivariate test (similarity test). The components of heart periods spectre, mean cardiac periods and their variation coefficients were determined from the RR intervals of ECG. The results of the similarity test show the change of respiratory cycle shape during voluntary hyperventilation compared with rest, but the shape of the cycle during HV is conserved during one year interval and between periods of HV of two tests THV and THV20. Voluntary hyperventilation changes significantly ventilatory characteristics (variables and shape of cycle). However, these characteristics are conserved during voluntary hyperventilation after one year interval and the rest ventilatory personality is not conserved during HV, but the different personality appears during HV. Ventilator variables and their variation coefficients are modified during all periods of the two hyperventilation tests. The ventilatory variables of the control group compared with TP group differ only during first three minutes of recovery. Heart rate variability is significantly modified during all periods of hyperventilation test. Heart rate variability is significantly diminished in TP patients compared with healthy subjects and the analysis of spectral components of cardiac period allows affirming a weaker cardio-vagal activity and higher sympathetic activity compared with the healthy subjects. The TP patients compared with control group have higher levels of anxiety and depression. The ventilation during three minutes of recovery after voluntary hyperventilation at rest frequency is higher in subjects with high anxiety level compared with subjects with normal and mean level of anxiety. The number of functional symptoms and symptoms caused by voluntary hyperventilation is also higher in subjects with high anxiety.

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.