Frequency Of Respiratory Movements Research Articles

Comparative analysis of the effect of Reamberin and Methadoxyl on the course of acute severe ethanol poisoning

Introduction. One of the ways to improve the quality of intensive therapy in severe forms of acute alcohol poisoning is the inclusion in the complex of measures of means capable of reducing the manifestations of oxidative stress. The aim of the work was a comparative evaluation of the effectiveness of drugs Reamberin and Methadoxyl in acute severe ethanol poisoning on rats. Materials and methods. Acute severe alcohol poisoning was modeled in Wistar rats by 40 % ethanol solution at a dose 8,6 g/kg. The studied drugs were administered infusively in the volume of 20 ml/kg for 60 min at an average rate of 0.33 ml/min/kg. The comparative efficacy of infusion therapy was evaluated according to the severity of coma and its duration. Results. Ethanol caused coma of different severity in animals. At the end of infusion therapy, the death of some animals was observed. The life expectancy of dead animals receiving Reamberin was 4 times higher than that of animals of the control group and animals receiving Metadoxyl. The most significant decrease in the severity of coma and its duration was observed in rats receiving Reamberin. Minimal differences in the frequency of respiratory movements from the background at the end of infusion occurred in the same animals. Discussion Established in acute ethanol poisoning the presence of supportive therapy with Reamberin of neurological status and external respiratory function during infusion is a justification for the inclusion of the drug in the complex of intensive care in this critical condition. Conclusions. It was experimentally shown that Reamberin, unlike Methadoxyl, significantly reduced the severity of alcohol coma at the end of infusion administration. Reamberin increased the life expectancy of dead animals compared to the control and rats receiving Methadoxyl, and also caused minimal differences in respiratory rate relative to the background at the end of infusion, which had the character of a trend. Reamberin demonstrated greater efficacy with respect to the course of acute severe ethanol poisoning than Methadoxyl.

Acute heart failure and cardiogenic arterial thromboembolism in cats: clinical and echocardiographic features

Acute heart failure and arterial thromboembolism are common complications of hypertrophic cardiomyopathy in cats. These conditions have many common links in pathogenesis, so analyzing the differences between them improves the understanding of the impact of vessel occlusion on the body. In the study, 40 clinical cases were analyzed and two groups were formed: the first – cats with arterial thromboembolism and the second – cats with acute heart failure. The data from anamnesis, clinical examination and echocardiographic examination were collected. Age, sex, breed, weight, temperature, frequency of respiratory movements, signs of dyspnea, presence of pulmonary edema, presence of free fluid in the chest and pericardial cavities were analyzed. The following echocardiographic parameters were analyzed: left ventricular wall thickness, left ventricular end-systolic and end-diastolic dimensions, diameters of the aorta and left atrium, heart rate and left ventricular contraction fraction. It was established that the majority of animals from both groups were males. Acute heart failure was registered mainly in young cats (M = 3.7), in contrast to animals with arterial thromboembolism (M = 6.7), (P < 0.01). There was no significant difference in the values of rectal temperature, weight, heart rate, aortic diameter, and left ventricular contraction fraction. Most animals from both groups had signs of dyspnoea. The difference in the frequency of respiratory movements was significant (P < 0.01). In cats with acute heart failure, pulmonary edema was diagnosed in 85%, free fluid in the thoracic and/or pericardial cavities in 55 %. In animals with thromboembolism, edema was found in 45 %, and effusion in the chest and/or pericardial cavities in 30 % of animals. The established differences indicate that arterial thromboembolism develops in animals that have had heart pathology for a longer period of time, whereas acute heart failure occurs more suddenly in cats.

PHYSIOLOGICAL STUDIES ON THE CARDIOPULMONARY INDEX CHANGES IN ADAPTATION TO PROGRESSIVE PHYSICAL LOADS

Objective. The main purpose of the research was to develop a coefficient of cardiorespiratory system status, which will take into account both frequency and power characteristics of external respiration and hemodynamics activity. Compare an informativeness of this coefficient with a universally accepted Hildebrandt one.
 Materials and Methods. 154 apparently healthy young people of both sexes were examined. On a bicycle ergometer with a pedaling rhythm of 40 per minute, five standard stages of short-term physical exercise load ranging from negligible to moderate were provided. Spirography, tonometry and pulsometry were carried out before loading, at its peak and after it. The parameters specified were recorded for each subject simultaneously. Systolic volume was calculated using Starr formula with subsequent defining cardiac minute output.
 Statistical analysis was performed using Statistica ® 7.0 package (StatSoft Inc., USA). Assessment of results’ significance was calculated using Student's t-test and sign test.
 Results. In the case of low short-term physical exercises pulmonary ventilation is increased due to greater reactivity of external breathing amplitude and to a lesser extent due to change in the frequency of respiratory movements. This type of reactions of the respiratory component in cardiorespiratory interaction is more efficient. In the given conditions, body’s adaptation is ensured by breathing component dominance, while responses of systemic arterial pressure and pulse turn out to be less pronounced, less stabile. Taking into account greater adaptive importance in power characteristics changes of respiratory and cardiovascular activity, a coefficient of cardiorespiratory system status is proposed – MBV/RMV (ratio of minute blood flow volume to respiratory minute volume). The given factor is demonstrated to have significantly greater informative value and sensitivity to generally recognized Hildebrandt coefficient.

Анализ вариабельности сердечного ритма студентов с разной частотой дыхательных движений

The article deals with the analysis of the initial vegetative status of students with different levels of physical activity and frequency of respiratory movements. The functional reserves of the body are subject to increased requirements not only for training activities, but also for the training load. In this regard, the purpose of this work is to analyze the heart rate variability in students, taking into account the level of physical activity and the frequency of respiratory movements. Registration and analysis of HRV was carried out using a modern complex electrophysiological laboratory “CONAN-4.5”. Mathematical processing of the ECG makes it possible to obtain a number of temporal, spectral and geometric indicators, thanks to which an objective assessment of the state of the autonomic nervous system, including its sympathetic and parasympathetic divisions, is carried out. This method allows you to explore and evaluate the mechanisms of regulation of the cardiovascular system, as well as the tension of regulatory systems. Statistical processing of the material was carried out using Statistica 10.0. Cardiac activity of students was assessed. The gradation of the numerical values of the tension index of the body's regulatory systems was proposed by Shiryaev O. Yu. and Ivleva E. I., who took into account that with severe stress and diseases, the tension index can increase to higher values. As a result, it was proposed to distinguish five types of IN: vagotonic, normotonic, sympathicotonic, suprasymaticotonic, and transboundary. The latter is characterized by an increase in the prevalence of the sympathetic nervous system in the range of more than 600 c.u. During the mathematical processing of the electrocardiogram, numerical values of the stress index were obtained. It was revealed that among the entire studied array of students (when differentiating the IWT calculated according to IN) «normotics» are characterized by an optimal ratio between the parasympathetic and sympathetic divisions of the ANS. When analyzing the electrocardiogram, the values of heart rate were obtained and a relationship was established with the stress index and the type of change or absence of rhythm disturbance in students with different vegetative status. The work established the relationship between the initial vegetative status and the frequency of respiratory movements in students with different vegetative status. Students were offered a test to determine the coefficient of physical activity. The coefficient of physical activity is the ratio of the average daily energy expenditure of a person to the energy expenditure at rest, to the so-called basal metabolic rate. We established the relationship between the stress index and the coefficient of physical activity in students with different vegetative status.

Assessment of the heart rate variability of students taking into account the level of motor activity

The article deals with the analysis of the initial vegetative status of students with different levels of physical activity and frequency of respiratory movements. The purpose of the work is to analyze the heart rate variability in students, taking into account the level of motor activity and respiratory rate. Materials and methods. Registration and analysis of HRV was carried out using a modern complex electrophysiological laboratory «CONAN–4.5». Cardiac activity of students was assessed. Results. It was revealed that among the entire studied array of students (when differentiating the IWT calculated according to IN) «normotics» are characterized by an optimal ratio between the parasympathetic and sympathetic divisions of the ANS. At the same time, the value of the coefficient of physical activity in the studied group was determined at the level of values 1.73±0.1. Output. For normal adaptation to physical activity in students, it is necessary to form a level of physical activity that quantitatively corresponds to the CFA of physical activity of at least 1.75.

STUDY OF BIOLOGICAL EFFICIENCY AND ECOLOGICAL TOXICITY OF BAIT FOR DESTRUCTION OF RATS AND MICE «BIOSAN» ON LABORATORY RODENTS

The results of research show that the bait for the destruction of rats and mice «Biosan» rats eat willingly, completely. At simultaneous setting, in portable feeders, standard granulated feed and feed substrates of the manufacturer, rodents prefer the latter.
 On the 2nd day in experimental rats there was a slight inhibition of behavioral reactions, frequent approaches to drinking. There was a slight increase in the frequency of respiratory movements – by 10 units on average. No clinical changes were detected in experimental mice.
 On day 3 of the study, the average respiratory rate increased to 155 units per minute. In animals, there was a tendency to increase heart rate - tachycardia by 8,95 %. In two cages with rats - refusal of food, in others - reduction of food intake by 35 %. In one specimen, the rat has a visible leak from the nostril, the hair is bulging, there are traces of subcutaneous bleeding around the anus, there is no reaction to touch. No clinical changes were detected in the experimental mice, the food was eaten.
 Blood tests showed anemia, leukopenia, thrombocytopenic purpura, characteristic of inflammatory processes in the respiratory tract and gastrointestinal tract.
 Interstitial pneumonia, rupture of the lateral venules of the left thigh, and cardiopathy were found in rats euthanized. On the fifth day, all experimental rats died.
 Experimental mice showed signs of anemia (mucosal cyanosis) and behavioral disturbances, loss of appetite, or refusal to feed.
 Experimental mice died for 7-8 days. The carcasses of animals are bluish, swollen, with signs of cardiopathy and pathology of the gastrointestinal tract.
 The results of histological examinations and morphometric parameters in organs and tissues indicate that the initial changes occur in the immune organs (lymph nodes and spleen), and then the pathological process involves the lungs, heart, kidneys, liver and other organs.
 Bait for the destruction of rats and mice «Biosan» is made from concentrate «Bromadialone, 1,0%, solution», which, according to the parameters of acute oral and dermal toxicity, belongs to the 2nd class of highly dangerous compounds in relation to DSanPiN 8.8.1.2.002 -98 and SOU 85.2-37-736: 2011; does not pose an inhalation hazard (the active substance is not a volatile substance), but has an extremely pronounced cumulative property.
 In the future it is planned to carry out complex deratization with the use of the drug «Bait for the destruction of rats and mice «Biosan».

ROLE OF RESPIRATORY RATE IN THE TOLERABILITY OF PERSONAL RESPIRATORY PROTECTION EQUIPMENT

The factor limiting the tolerance of personal respiratory protection equipment should be considered the frequency of respiratory movements, which reflexively changes when additional respiratory resistance occurs. Unfortunately, there is almost no information in the available literature about changes in the tolerability of personal respiratory protection equipment at different rates of respiratory movements. The purpose of this work was to study the tolerability of personal respiratory protection equipment when changing the frequency of respiratory movements.The study was conducted on practically healthy persons of both sexes (78 people), aged from 20 to 36 years. To simulate the conditions for the use of personal respiratory protection equipment, inspiratory resistive respiratory loads of 20% of the maximum intraoral pressure during the Mueller test were used. The tolerance of personal respiratory protection equipment was assessed using the Borg visual analogue of dyspnea scale, which reflected the level of subjective discomfort that occurs when additional respiratory resistance is turned on. During the action of additional respiratory resistance, the persons were asked to hold the frequency of respiratory movements, which was set using a special setting.An increase in the rate of respiratory movements against the background of additional respiratory resistance leads to a significant deterioration in the objective and subjective indicators of the functional state of the persons; replacing the inhaled air with an oxygen-rich respiratory mixture with carbon dioxide absorption did not lead to a significant improvement in the functional state. A moderate decrease (up to 70% of the initial frequency of respiratory movements) in the rate of respiration leads to an improvement in the indicators of adaptive activity in conditions of additional respiratory resistance. A significant decrease (up to 35% of the initial frequency of respiratory movements) in the rate of respiration under conditions of additional respiratory resistance leads to a deterioration of objective and subjective indicators of the functional state of the subjects.An increase in peak respiratory flow rates caused by an increase in the rate of respiration, in accordance with the well – known Rohrer equation, significantly increases inelastic resistance and, as a result, respiratory needs. These needs can be met at some time due to a significant increase in the work of the respiratory muscles, but due to fatigue of the latter, psychoemotional tension increases quite quickly and the use of personal respiratory protection equipment is abandoned.

Cardiopulmonary Index of Organism Adaptation to Low Physical Exercises of Increasing Power

Objective. The main purpose of the research was to develop a coefficient of cardiorespiratory system status, which will take into account both frequency and power characteristics of external respiration and hemodynamics activity. Compare an informativeness of this coefficient with a universally accepted Hildebrandt one. Materials and Methods. 154 apparently healthy young people of both sexes were examined. On a bicycle ergometer with a pedaling rhythm of 40 per minute, five standard stages of short-term physical exercise load ranging from negligible to moderate were provided. Spirography, tonometry and pulsometry were carried out before loading, at its peak and after it. The parameters specified were recorded for each subject simultaneously. Systolic volume was calculated using Starr formula with subsequent defining cardiac minute output. Statistical analysis was performed using Statistica ® 7.0 package (StatSoft Inc., USA). Assessment of results’ significance was calculated using Student’s t-test and sign test. Results. In the case of low short-term physical exercises pulmonary ventilation is increased due to greater reactivity of external breathing amplitude and to a lesser extent due to change in the frequency of respiratory movements. This type of reactions of the respiratory component in cardiorespiratory interaction is more efficient. In the given conditions, body’s adaptation is ensured by breathing component dominance, while responses of systemic arterial pressure and pulse turn out to be less pronounced, less stabile. Taking into account greater adaptive importance in power characteristics changes of respiratory and cardiovascular activity, a coefficient of cardiorespiratory system status is proposed - MBV/RMV (ratio of minute blood flow volume to respiratory minute volume). The given factor is demonstrated to have significantly greater informative value and sensitivity to generally recognized Hildebrandt coefficient.

The ordinal scale of X-ray assessment of venous congestion in chronic heart failure

Aim. To develop an ordinal scale for x-ray assessment of venous congestion in chronic heart failure based on the results of the standard assessment of chest radiographs.
 Methods. The ordinal assessment on the scale consists of a numerical expression of four radiological symptoms: cardiomegaly, pleural effusion, and changes in the pulmonary pattern due to vascular and interstitial components. The presence of each of these symptoms corresponds to a score of 1 point. In the result, ordinal X-ray assessment varies from 0 to 4 points. Simultaneously objective clinical, instrumental and laboratory measures of the severity of congestive heart failure were recorded in patients.
 Results. Cardiomegaly, the presence of pleural effusion and changes in the pulmonary pattern due to vascular and interstitial components was numerically estimated according to the standard assessment of chest X-rays for the scale of radiological assessment of venous congestion. Correlation between numerical estimates of the ordinal scale and objective clinical, instrumental and laboratory measures of venous stasis in the sample of 225 patients showed the validity of the assessment. The statistically significant direct relationships between value of the ordinal scale for X-ray assessment of venous congestion with functional class and stage of chronic heart failure, the level of NT-terminal fragment of brain natriuretic peptide, the frequency of respiratory movements, the scale of clinical state, the index of the left atrium, the systolic pressure in the pulmonary artery, as well as an inverse dependence with the 6-minute walk test values were proved. Sufficient internal consistency of the ordinal scale was demonstrated (Cronbach's alpha 0.73). We also found that the scale demonstrated predictive informativeness, which was manifested by a significant increase in the mortality of patients with chronic heart failure in cases where the scale values increase to 2.
 Conclusion. The proposed ordinal scale for x-ray assessment of venous congestion has sufficient reliability (internal consistency) for practical application, as well as criteria and prognostic validity; the scale can be considered as a simple, accessible and informative addition to the standard examination of polymorbid patients with chronic heart failure, which may be useful for advanced assessment of the patient's condition and risk of death within the next year.

Efficacy of Application of Dietary Supplements in Acute Intoxication

The effectiveness of BAA balsam "Revival plus" as a means of pharmacological correction of neurotoxic and hepatotoxic lesions as consequences of acute ethanol poisoning was evaluated. It has been established that in the conditions of acute severe intoxication ethanol BAA balsam "Revival plus" has pharmacological efficacy in terms of survival keeping temperature and frequency of respiratory movements in poisoned rats with a therapeutic and prophylactic scheme of their use. Value of the work consists in the experimental substantiation of the possibility of using BAA balsam "Revival plus" as a promising means of treatment of acute extremely severe ethanol poisoning. The aim of this paper is to demonstrate the efficacy of application of dietary supplements in acute intoxication, to depict the effectiveness of balsam during the intoxication, and from scientific purpose to prove the significance of this supplement. The obtained data testify to the effectiveness of the use of bio additives in ethanol poisoning and possible mechanisms for the implementation of the hepatic protective effect of the BAA balsam "Revival Plus" under various life-threatening conditions. The purpose of this research is evaluation of the experimental effectiveness of BAA balsam "Revival Plus" for ethanol poisoning. To achieve this goal the following tasks are set: To reveal the features of the histological structure of the liver of control and experimental rats of the second group with ethanol poisoning; To study the morphological changes in the liver of rats of the third group with ethanol poisoning against the background of the use of BAA balsam "Revival plus"; To study the peculiarities of the action of the BAA balsam "Revival plus" on the biochemical parameters of the blood of rats. Questions about the interaction of dietary supplements and alcoholic beverages are regularly being raised by both researchers and ordinary consumers. In most cases talk about the dangers of dietary supplements for a person who often drinks alcoholic beverages is not necessary.

Калькулятор «Доступный прогноз» – способ качественной оценки выживаемости пациентов c сердечной недостаточностью с низкой фракцией выброса левого желудочка

A method for predicting one-year survival of patients with heart failure and reduced ejection fraction (HFrEF) is required to choose a management tactics and determine indications for high-tech care at the outpatient stage. To develop a method for proper prediction of survival of patients with HFrEF in outpatient clinics. This was a prospective study of 212 patients with functional class II-IV CHF of non-valvular origin and LV EF (Simpson) ≤35 % aged 18-70, including 176 (83 %) men and 36 (17 %) women who had given an informed consent to participate in the study. hospitalization to a specialized department for treatment of heart failure; best titration of tolerated doses and stabilization of the patient's condition; evaluation of status; laboratory and instrumental tests; outpatient follow-up by an HF specialist (visits, telephone contacts, therapy adjustment, and admission to a specialized HF department in case of decompensation); 200‑item database population; recording the composite endpoint (cardiovascular death, or implantation of a mechanical circulatory assist (MCA) device, or heart transplantation (HT) within 12 months). For 12 months, 135 (64 %) patients survived; a MCA device was implanted to 5 (2 %) patients; HT was performed for 21 (10 %) patients; and a fatal outcome was observed in 51 (24 %) patients. Therefore, 77 patients had the composite endpoint. A method for predicting survival was developed using a multiple logistic regression analysis. The developed proper method for survival prediction included the following parameters: age of HFrEF onset; frequency of respiratory movements; systolic blood pressure measured at 3-5 min of orthostasis; lymphocyte count, and red cell distribution width. An identified patient with a predicted survival less than one year should be as soon as possible forwarded to a selection panel for considering HT or MCA implantation as a «bridge» to HT. A predicted survival longer than one year is an indication for further outpatient management and considering cardioverter defibrillator implantation. The method for proper outpatient evaluation of survival prognosis for patients with HFrEF allows to predict the one-year survival using routine indexes, such as results of objective examination, case history, and blood count, without additional expenses.

Irregular amplitude and frequency of respiratory movements in hemispheric stroke

Objectives: The aims of the study were to investigate respiratory movement patterns among patients with right versus left hemispheric stroke with emphasis on regularity of respiratory frequency and amplitude of movements during both quiet and voluntary deep breathing and to compare the results with reference values.Materials and methods: Eighteen patients with severe stroke were measured with the Respiratory Movement Measuring Instrument. Respiratory frequencies, movements, regularity of amplitude and frequency were compared with individuals with no neurological disease.Results: The demographics and physical performance were comparable for 8 left and 10 right hemispheric stroke. Deep respiratory movements were significantly decreased (p < 0.001) and frequency significantly increased (p < 0.03 for quiet and p = 0.002 for deep breathing), for the group (n = 18) compared with reference values. Fifty-six percent of our stroke patients had irregular amplitude of deep respiratory movements (p = 0.003), and 33% had irregular frequency (p = 0.058), but none of the individuals with no neurological diseases (p = 0.003). Seventy percent of RHS patients had irregular amplitude of deep respiratory movements, compared with 38% of LHS patients (p = 0.34).Conclusion: Results show significantly decreased amplitude of deep breathing in hemispheric stroke and indicate a possible effect on regularity of range and frequency of respiratory movements.

The influence of different modes of ventilation on standing balance of athletes.

Background:The respiratory movements are one of the factors influencing standing balance. Although well-trained athletes have better postural performance compared to untrained men, it's not quite clear, if the formers' upright posture would be more stable during different ventilation modes, maximal voluntary hyperventilation and inspiratory breath-holding. There are no studies on this subject in the available literature.Objectives:The aim of this study was to investigate an influence of maximal inspiratory breath-holding and maximal voluntary hyperventilation on the standing balance of athletes.Patients and Methods:We assessed the amplitude and the velocity of postural sway in the athletes (n = 38) and untrained subjects (n = 28) by the force platform. The frequency characteristics of the center of pressure (CP) oscillations' were also analyzed. The amplitude and the frequency of respiratory movements were estimated by the strain gauge.Results:It was found that during quiet breath velocity and frequency of CP oscillations were lower in the athletes. Breath holding led to an increase of velocity and frequency of CP displacement in both groups, increase of these indices was more pronounced in the athletes. Maximal voluntary hyperventilation caused a significant increase of all stabilographic indices in both groups. Increase of frequency and amplitude of respiratory movements were mainly observed during hyperventilation in athletes and it caused an increase of the velocity of CP displacement. Changes of sway amplitude were the same in both groups.Conclusions:Breath holding led to activation of the postural control, which was more pronounced in the athletes. Hyperventilation caused an impairment of the postural stability. The athletes' postural system compensated the impact of hyperventilation more efficiently versus controls, but it was achieved at the expense of greater effort.

Loss of Heart Rate Variability in Parkinson's Disease Shown by the Poincare Plots during Rhytmic Breathing (P05.196)

Objective: To study the variability of the heart rate with Poincare plot in patients with Parkinson9s disease (PD). Background The loss of heart rate variability (HRV) has been demonstrated in a large proportion of patients with PD. During rhythmic breathing (RB) the cycles of bradycardia and tachycardia are readily observed and the time series of RR intervals (RRI) are stationary. Poincare plots obtained during this condition are relatively easy to make and have a clearcut interpretation. Design/Methods: We studied seven patients with PD and compared their HRV to twenty healthy controls. We studied standard deviation 1 (SD1, transverse SD), SD2 (longitudinal SD), SD2/SD1 ratio and the total area of the ellipse (Cn). We also made the FFT of time series of the RRI and constructed frequency plots at low and high frequencies (LF, HF). We also obtained the peak frequency of HF and LF. The frequency of respiratory movements was 0.1 Hz Results: All the studied variables were abnormally low in the patients with PD (SD1 12.24±5.21, SD2 33.8±17.02, Cn 1473.01±1100.23, SD2/SD1 2.79±0.97) compared to the healthy controls (SD1 43.86±21.15, SD2 130.79±52.24, Cn 21190.31±18479.28, SD2/SD1 3.13±0.50) and the data reported in the literature. The analysis in the frequency domain showed a shift to the right of the peak of LF and HF domains. Conclusions: The decrease in SD1, SD2, SD2/SD1 ratio and Cn revealed severe cardiosympathetic and cardiovagal damage. The shift to the right of LF and HF peaks in the frequency plots reveal a delay of response of the cardiosympathetic and cardiovagal reflexes. Poincare plots could be useful in clinical practice for the cardiovascular autonomic evaluation of these patients. Disclosure: Dr. Estanol has nothing to disclose. Dr. Delgado has nothing to disclose. Dr. Bertado has nothing to disclose. Dr. Callejas has nothing to disclose. Dr. Medina has nothing to disclose. Dr. Infante has nothing to disclose. Dr. Lerma has nothing to disclose.

162 Long-Term Cardio-Respiratory Regulation in Children with Rett Syndrome

Background: The cardiac and respiratory function requires an intricate coordination of afferent/efferent signals at several levels to secure homeostasis. Rett syndrome is characterised by a functional disintegration of physiological functions. Autonomic function in Rett syndrome has been studied mainly during short time spans (minutes-1 hour). In order to capture the full complexity of the autonomic function – a long-term study of the cardio-respiratory regulation was performed. Methods: Patients with Rett syndrome in the Stockholm area were studied during one week in their home environment (n=15). Heart rate and breathing were recorded via standard three-lead ECG electrodes. The depth and frequency of respiratory movements were measured via changes in impedance. Oxygenation was measured by pulse oxymetry. Care takers were asked to fill out a form during the monitoring enabling us to analyze the correlation between behaviour and cardio-respiratory reactions. Results: All subjects revealed respiratory dysfunction and a majority had bradycardia and/or tachycardia. In accordance with our previous findings, disturbances in cardio-respiratory function were present both when awake and asleep. Interestingly, there were pronounced variations in cardio-respiratory regulation from day to day and even from hour to hour in an individual patient. Furthermore, we also observed variations in cardio-respiratory events between individuals and situations. Conclusions: Cardio-respiratory function in children with Rett syndrome is characterised by dramatic instability during wakefulness and sleep and differ among individuals. Cardio-respiratory regulation varies from hour to hour and between different situations in the individual Rett girl. Therefore, a long-term monitoring is decisive for adequate diagnostics and treatment.

Disturbances in Cardiorespiratory Function During Day and Night in Rett Syndrome

Rett syndrome causes severe autonomic dysregulation, probably due to brainstem dysfunction. Because the brainstem plays a decisive role in cardiorespiratory regulation during sleep, we investigated cardiorespiratory function in 12 girls with Rett syndrome, day and night, for 1 week in their home environment. Heart rate and breathing were recorded via standard three-lead electrocardiogram. Depth and frequency of respiratory movements were measured via changes in impedance. All children were scored clinically, and the association with cardiorespiratory function was examined. The total recording time for all patients was 1114 hours (535 during wakefulness; 579 during sleep), and 77 +/- 22 hours (median +/- standard error of the mean) per individual. All subjects manifested apnea, shallow breathing, or hypoventilation, when awake and during sleep. A majority had bradycardia or tachycardia. The frequencies of respiratory and heart alarms were similar during wakefulness and sleep. Bradycardia events predominated during sleep. The only significant correlation between clinical score and cardiorespiratory regulation was found for muscular-skeletal function and breathing abnormalities during wakefulness. We conclude that Rett syndrome is characterized by disturbed breathing and heart rate during sleep. The severity of cardiorespiratory dysfunction exhibited marked intra- and interindividual differences.

Motor and behavioural effects induced by putative neurotransmitter injection into the optic lobe of the cuttlefish, Sepia officinalis.

This paper presents a technique using local injections of different drugs directly into the optic lobe of Sepia. The cholinomimetic drugs induce a general decrease of the motricity, muscle tone, frequency of respiratory movements and decoloration of the animal. Dopamine and noradrenaline produce the same complex motor effects obtained by chronic electrical stimulation. Serotonin induces complex effects, particularly on the coloration. Some serotoninergic synapses could be implicated in the triggering of colour patterns.

Effect of repeated muscular work on pulse rate and blood pressure

Changes in lung ventilation, frequency of respiratory movements, pulse rate, blood pressure and oxygen saturation of arterial blood have been studied during dynamic and static work.

TEMPERATURE CHARACTERISTICS FOR FREQUENCY OF RESPIRATORY MOVEMENTS IN YOUNG MAMMALS

The internal temperature of 2 day old mice deviates by +0.01 degrees to +3.0 degrees C. from the environmental temperature over a range of 24 degrees . The undeveloped temperature control allows rhythmic activities in this mammalian material to be readily subjected to the analysis afforded by temperature characteristics, and thus makes possible some insight into the physicochemical events controlling vital processes in entire uninjured mammals. The thermal increments and critical temperatures obtained point to a similarity in the controlling system of reactions for both homothermic and poikilothermic organisms. For frequency of respiratory movements the increments 12,340 (19.6 degrees to 35.2 degrees C.); 28,340 or 36,500 (15.5 degrees to 19.6 degrees C.) are most frequently found (thirteen cases). Rarely micro = 8,450, 33,000, or 18,340 (two cases). The last increment is either associated with micro = 36,000 below 20 degrees , or extends unbroken throughout the whole range (one case).

The Relation of the Rate of Blood Flow Through the Medulla Oblongata to the Amplitude and Frequency of Respiratory Movements

The Relation of the Rate of Blood Flow Through the Medulla Oblongata to the Amplitude and Frequency of Respiratory Movements