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Opportunities to examine patients with spastic angina pectoris are at present, due to the inaccessibility of ergonovine, very limited. The authors demonstrate on a small group of patients the application of echocardiographic hyperventilation test for assessment of the diagnosis of spastic angina pectoris.
To elucidate the relationship between cerebral blood flow (CBF) after hyperventilation (HV) and the rebuild-up phenomenon on the encephaloelectrogram (EEG) in children with moyamoya disease, comparative study of CBF immediately after HV and CBF after administration of acetazolamide (Diamox) was examined. CBF was measured by means of single photon emission CT (SPECT) using the 133Xe inhalation method. The subjects were 11 children (21 hemispheres) with moyamoya disease who were divided into two groups as follows, 1) Bypass group; who underwent STA-MCA anastomosis with other synangiosis. 2) Non-Bypass group; who underwent only some synangiosis such as EDAS, EMAS, EMS. The summary of the results is shown below. Regional CBF (rCBF) after HV of the frontal lobes in the Non-Bypass group had an evident tendency to show low perfusion compared with CBF in other regions. The correlation between low perfusion area after HV, and areas where the increase of rCBF is less after administration of acetazolamide became clear. The strongest relation was observed between low perfusion after HV and re-build-up phenomenon on EEG. On the other hand, rCBF after HV of the frontal lobes in the Bypass group had, compared with other regions, no tendency to show low perfusion. From this study and our previous reports, it is assumed that there is some hemodynamic insufficiency in the frontal lobes of the Non-Bypass group. The reason why the reduction of rCBF was less after HV especially in the frontal lobes of the Bypass group is still unknown.(ABSTRACT TRUNCATED AT 250 WORDS)
BACKGROUND: This article evaluates the prevalence of hyperventilation syndrome (HVS) in patients who continue to complain of ongoing nasal congestion, despite an apparently adequate surgical result and appropriate medical management. METHODS: Prospective case series of 14 patients from June 2002 to October 2003 was performed. Patients, who presented complaining of nasal congestion after previous nasal surgery and who appeared to have an adequate nasal airway with no evidence of nasal valve collapse, were evaluated for HVS. When appropriate, nasal steroids and oral antihistamines also had been tested without success. Three patients had end-tidal P(CO2) levels measured and five patients underwent breathing reeducation. RESULTS: All patients had an elevated respiratory rate (>18 breaths/minute) with an upper thoracic breathing pattern. Twelve of the 14 patients complaining of nasal obstruction had an elevated Nijmegen score indicative of HVS. An average number of 2.5 procedures had been performed on each patient. End-tidal P(CO2) levels were < or = 35 mmHg in the three patients who had expired P(CO2) levels measured. Breathing retraining was successful in correcting the nasal congestion in two of five patients. CONCLUSION: HVS should be included in the differential diagnosis of patients presenting with nasal congestion, particularly after failed nasal surgery. One possible explanation is increased nasal resistance secondary to low arterial P(CO2) levels. Another possible explanation is reduced alae nasae muscle activity secondary to the reduced activity of serotonin-containing raphe neurons. Additional surgery may not necessarily be the answer in HVS patients complaining of nasal congestion.
Analysis of the psychophysiological characteristics was made in patients suffering from vegetative paroxysms of the psychogenic nature. The patients were distributed into 2 groups: group I included patients (n = 35) with a well-defined hyperventilation syndrome (HVS) in the structure of vegetative disorders, group II was made up of patients (n = 23) with the same vegetative disorders without the HVS. 20 healthy subjects served as control. The clinical and psychological assays and analysis of the vegetative characteristics including respiration revealed common mechanisms in both the groups. Besides, the patients with and without HVS manifested appreciable differences in the functioning of the cerebral systems that control the respiratory pattern.
The aim of the study was to evaluate the effects of hyperventilation test (HVT), active orthostatic position test (AOPT), and their combination on the vegetative homeostasis in male students with risk factors of atherosclerosis (RFA) and endothelial dysfunction (ED). The mentioned tests and their combination were performed in 142 male students with RFA and ED, and 54 male students without them during brachial arterial rheovasography and cardiointervalography. Hyperactivation of the central regulatory circuit and a spastic hemodynamic condition at rest were found in subjects with FRA and ED. The sympathetic functional reserve was overstrained according to AOPT, distinctly decreased according to HVT, and exhausted when both tests were performed. The combination of HVT and AOPT is an informative stress test for pre-clinical evaluation of disturbances in adaptation mechanisms and vegetative homeostasis tensity in young men with RFA and ED. A "high value" of adaptation and the vegetative homeostasis overstrain in male students with FRA and ED indicate a premorbid condition in them.
Deviations of the alveolar ventilation rate from normality induce respiratory acid-base disturbances. Alveolar hyperventilation leads to hypocapnia and thus respiratory alkalosis whereas alveolar hypoventilation induces hypercapnia leading to respiratory acidosis. The changes in CO2 induce compensatory alterations of renal bicarbonate transport: Hypercapnia stimulates renal reabsorption of bicarbonate whereas hypocapnia enhances urinary bicarbonates. The plasma bicarbonate concentration rises in response to hypercapnia and falls following hypocapnia. Renal regulation of plasma bicarbonate results in a characteristic dependence on systemic PCO2 permitting the formation of diagnostic criteria for respiratory imbalance of acid-base homeostasis. In chronic respiratory acidosis plasma bicarbonate should rise by 0.35 mmol/l per mmHg increase in PCO2. In chronic respiratory alkalosis, on the other hand, plasma bicarbonate should fall by 0.4 mmol/l for every mmHg decrease in PCO2. If the measured bicarbonate values do not fall into this expected range, acute respiratory or mixed (respiratory and metabolic) acid-base disturbances should be suspected. The clinical significance and application of these diagnostic criteria are illustrated by examples.
The paper is concerned with elaboration of criteria for spiroergometric assessment of the level of load hyperventilation (LHV) in patients with heart diseases before and after surgical correction. Study of the dynamics of the correlation between CO2 production and ventilation underlies the method suggested. Four grades of LHV are distinguished: mild, moderate, pronounced and dramatic. It is shown that the pronounced and dramatic grades of LHV may provide indirect evidence for high pulmonary hypertension (stage II or III).
Using a modification of the computer period analysis of the EEG (Aladjov and Daskalova 1987) we studied the late after-effects (until the 30th min) in human EEG (monopolar leads at F1, C3, P3 and 01) following two kinds of influences: a) short interoceptive one: 3 min hyperventilation (HV) and b) a series of 5 trains of visual light flashes (VS), presented in 5-7 min intervals. The changes in the ongoing EEG in the 2nd min after each VS and in intervals of 5 min after HV were compared with the values before the stimulation. VS did not elicit long-lasting EEG after-effects, which characterized the single interoceptive influence (HV) and consisted mainly of beta-2 (24-36 Hz) EEG activity increase in all studied cortical regions (Nikolov and Kisselkova 1988). Moreover, the exteroceptive stimulation (VS) had no essential influence on the late EEG after-effects after HV, when both kinds of stimulation were applied in the same experiment.
The late EEG after-effects following application of a short-lasting ventilatory interoceptive influence (3 min hyperventilation-HV) were studied in humans with three degrees of adaptation: students (ST) with a lower degree of training, professional alpine climbers with a high level of training (AL1) and the same subjects (AL2) in a middle position of adaptation i.e. 6 months after an expedition. ST developed late EEG after-effects, consisting mainly in an increase of the beta-2 EEG activity; AL1 showed very slight changes, while in AL2 the EEG after-effects were intermediate. It is suggested, that a lower level of adaptation facilitates the triggering through HV of processes in the cortical EEG which accompany an improvement of the brain tone.
The principal methods of the treatment of the hyperventilation syndrome (HVS) are reviewed. The following methods of the action on the patient are distinguished: psychotherapy, pharmacotherapy, remedial gymnastics, correction of respiratory disorders according to the principle of the biological feed-back mechanism, recurrent respiration or carbon dioxide inhalations. Emphasis is laid on the importance of an individual approach to the institution of the treatment measures. The relationship between the HVS and respiratory diseases is discussed. The authors advance an opinion that every patient may note improvement after receiving a properly selected complex of the treatment measures.
The case study presents a patient with severe disturbance of self-esteem, suicidal family-background, narcissistic trauma and psychosomatic illness in form of a hyperventilation syndrome in the light of his heart transplantation. Helplessness and hopelessness of his psychological situation, his fear of separation, his paralyzing inability to come to any decision are seen against the background of a situation of absolute stress in which he had to struggle against his anxieties and fears and presumptions about the donor organ. There also is discussed whether a patient with such severe disturbances should really be accepted as a donor organ recipient, as well as whether in this case a supportive or analytic therapy would have been the appropriate choice. Annotations of the author about personal difficulties in therapy and at last its failing are added.
To assess the effectiveness of terfenadine on bronchoconstriction in asthmatics, 12 asthmatic patients between the ages of 19 and 43 were challenged with ultrasonically nebulized distilled water (UNDW) and treated with terfenadine, 120 or 240 mg, or placebo in a three-way crossover double-blind study. A similar study of 12 asthmatics (nine from the UNDW trial) was performed using cold-air hyperventilation challenge (CAHC). In vitro analyses were also made of samples from ten mild asthmatics to determine the effect of terfenadine on basophil histamine release. Terfenadine, 240 mg, showed significant (P = .012) benefit over placebo in improving pulmonary function after UNDW challenge. Modest but significant (P less than .05) bronchodilator benefits were also demonstrated by terfenadine, 240 and 120 mg, after CAHC. Finally, the in vitro study showed significant inhibition by terfenadine of anti-IgE-induced histamine release from human basophils.
We examined ischemic and hyperventilation tests in 14 pairs of healthy twins. In 3 of them we found different results of positivity or negativity of these tests. Women had signs of higher irritability of the wave M than men as concerned latency, amplitude, duration; the strength of stimulus was significantly lower in females than in males.
We examined 554 patients with clinical suspicion of tetanic syndrome whose ischemic and hyperventilation tests were negative. We analysed the wave M before carrying out the tests with the following parameters: latency, amplitude, duration, shape and strength of stimulus. We could register higher irritability in women, in young persons, in course of years. We cannot register conspicuous changes during year seasons; the amplitude and the strength of stimulus were in middle correlation. We try to explain the significance of the polyphasic shape of the wave M where the desynchronization and repetitive activity are supposed to be the main causes. The relation between men and women was 1:2.2. Most patients were in the middle age group.
A review of literature comprises the main data on etiological factors, pathogenetic mechanisms, clinical peculiarities and methods of diagnosis of the hyperventilation syndrome. Physicians' insufficient knowledge of this disease is emphasized. Various clinical manifestations are based on the same pathogenetic mechanisms of acute or chronic respiratory disregulation resulting in hypocapnia, a rise of vascular tone, and electrolytic disorders. Of great practical importance is the use of a unified clinical classification, of which a variant is proposed by the authors. The main therapeutic modalities are: 1) psychotherapy, 2) pharmacotherapy, 3) exercise therapy.
Two male English springer spaniel dogs with a chronic hemolytic anemia and sporadic hemolytic crises, historically related to "stress" situations, were studied. Although canine erythrocytes are in general known to be more alkaline fragile, erythrocytes from both patients began to lyse earlier, at significantly lower pH values (near pH 7.4 at 37 degrees C), than erythrocytes from control dogs. Hyperventilation induced by 30 minutes of exercise, placement in a 39 degrees C water bath, or intravenous doxapram increased venous blood pH in dog 1 and control dogs, but transient hemoglobinemia, hemoglobinuria, and severe bilirubinuria occurred only in the studied patient. The erythrocyte phosphofructokinase (PFK) activity was severely decreased in both dogs (10% of controls). The erythrocyte 2,3-diphosphoglycerate content was markedly reduced and the cell chloride content was consequently increased. This change in cell chloride content is related to an increase in the erythrocyte pH, which may partially explain the pathogenesis of hemolysis in canine PFK deficiency. Thus, these studies demonstrate a presumably inherited erythrocyte PFK deficiency in English springer spaniels, which causes an increased in vitro and in vivo erythrocyte alkaline fragility. Dogs with PFK deficiency and inducible hemolytic crises may become a valuable genetic animal model in which to study the pathophysiology of hemolysis.
The application of two kinds of ventilatory interoceptive influences with opposite effects on the acid-base balance (hyperventilation and breath holding) results in appearance of late nonspecific after-effects in human EEG, which do not disappear until the 30th min after the stimulation. They consist in local and spatial synchronizing processes in the alpha and beta EEG spectrum, being most pronounced in the beta-2 range (23-36 Hz). These changes are considered as a sign of a development of readjustment in the functional state of the central nervous system in the direction of its improvement. The triggering of this readjustment is largely determined by the considerable changes in the internal medium, leading to intensified interoceptive signalization (mechanical, chemical and proprioceptive), as well as to the development of a brief cerebral hypoxy, followed by improved brain blood flow.
Subjective differences in EEG evaluation are demonstrated by means of a seven step scale for grading the unspecific hyperventilation effect in 3263 EEG of children. Intermediate steps of this scale allow to minimize such unavoidable differences.