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PubMedDate not supplied

[Parasites of the respiratory system: research and significance (author's transl)].

A review is made of the methods of diagnosing both autochthonous and exotic protozoal and helminthic diseases of the respiratory system. Referring to protozooses, recent findings on respiratory pathology due to amoebae of the genus Acanthamoeba are commented, and modern methods are discussed of checking for Pneumocystis carinii in the patient, not just on autopsy material. Referring to helminthiases, in addition to pulmonary echinococcosis which is of prevalent interest in Italy, attention is also given to the pathology of migrant larvae of nematodes. Finally, the role of some microscopic mites in the pathogenesis of respiratory allergic disease from house dust is discussed.

Amoeba↗
PubMed1982

Reduction in resting end-expiratory position of the respiratory system with induction of anesthesia and neuromuscular paralysis.

Resting end-expiratory position (REEP) of the respiratory system was monitored continuously using spirometric recording in eleven patients during transition from consciousness to thiopental hypnosis and following subsequent administration of succinylcholine. REEP decreased following thiopental and was little affected by subsequent relaxant in most patients. A fall in REEP was observed within 30 s after thiopental, and a lower, stable level of REEP was attained within approximately 15-45 s. Mean volume of gas expelled from the lungs was 189 (SE 32) ml BTPS. It is concluded that the previously extensively documented decrease in functional residual capacity associated with anesthesia occurs immediately on induction and requires a short, but finite, time for apparent stabilization.

Adolescent↗
PubMed1995

Reliability of clinical assessments of respiratory system compliance (Crs) made by junior doctors.

OBJECTIVE: To assess the reliability of estimates of static respiratory system compliance (Crs) made by junior hospital doctors caring for ventilated newborn infants. DESIGN: A prospective comparison of junior doctors' estimates of Crs to the Crs measured immediately afterwards. SETTING: A regional neonatal intensive care nursery in Edinburgh, Scotland. PATIENTS: 46 ventilated newborn infants. MEASUREMENTS AND RESULTS: Crs was estimated by three grades of junior doctor (Senior House Officer, Registrar and Research Fellow) using two different methods, (i) based on visual assessment of tidal volume in relation to inflation pressure (optical Crs) and (ii) directly using a visual analogue scale (analogue Crs). The Crs was then measured immediately afterwards using the single breath passive expiratory flow technique. The differences between the estimates and the measurements were calculated for each grade of observer and plotted against the corresponding measurements. The relationship between estimates and measurements was also expressed in terms of the coefficients of determination r2 calculated by least squares regression. With both methods of estimation observers tended to overestimate the Crs of infants with lower measured Crs and underestimate that of infants with higher measured Crs with many estimates differing from the measurements by more than 50%. Values of r2 ranged from 0.086 to 0.481 indicating a weak relationship between the estimates and the measurements. CONCLUSIONS: Junior doctors' estimates of Crs were unreliable and did not represent a useful method of assessing respiratory function. The clinical use of compliance measurements merits wider evaluation.

Humans↗
PubMedDate not supplied

[Dynamic morphological changes observed in the respiratory system immediately after craniocerebral trauma].

Microscope and morphometry examinations of specific structural changes observed in the respiratory system in death immediately after severe craniocerebral trauma denoted profound lesions with a certain sequence of progression. The extent of histomorphological changes in the lungs is shown to be influenced by a life span of victims after inflicted trauma, i.e. by the prescription of trauma.

Adult↗
PubMed2006

Development of the respiratory system in marsupials.

Marsupials at birth are small and relatively undeveloped. At birth, the lung in some species is at the canalicular stage of development and though lung diffusion and metabolic rate are strongly correlated, the allometric exponent suggests that smaller newborns have relatively smaller diffusing capacity with respect to their demand for oxygen. Without improvement in functional or structural parameters newborn marsupials are reliant to varying degrees on skin gas exchange to compensate for the immaturity of the lung. Indeed, in some species there is complete reliance on the skin for gas exchange at birth. Nevertheless, with an early dependence on ventilation, the CNS would appear already to contain neurons with properties and connections that permit rhythmic motor output at birth and pulmonary reflexes mature soon after. Despite appropriate neural control and the presence of surfactant, the highly compliant nature of the newborn chest wall results in substantial chest wall distortion during inspiratory effort which reduce the efficacy of the lung for ventilation. This review explores the morpho-functional development of the respiratory system, including oxygen transport and cardiac shunts, and the establishment of convective requirement in marsupials, a group that places emphasis on extended postnatal development.

Animals↗
PubMed2000

Nervous regulation of breathing in opiate dependent patient. Part I. Respiratory system efficiency and breathing regulation in the first stage of controlled abstinence.

Neurotoxic properties of opioid drugs which are the central nervous system depressant may have also depressive action on the brain stem complex responsible for the breathing control. Disorders of breathing regulation are reflected in respiratory efficiency. The aim of this study was to evaluate the regulation of breathing by measuring of respiratory pattern parameters, occlusion pressure and also to estimate the respiratory efficiency in opiate abusers. There were 76 persons under examination: group I--36 opiates abusers (29 men and 7 women; mean age 22.6 years) treated in the Detoxification Unit of the Department of Clinical Toxicology; group II (control group)--40 healthy persons (25 men and 15 women; mean age 28 years) not dependent of opiates and never treated at the Department. During hospitalisation the functional state of respiratory system was monitored. Ventilation efficiency was determined on the basic of the results from a "flow-volume" curve, spirometry and the measurements of the respiratory tract resistance in a computerised system Lungtest-MES company (Poland). Respiratory regulation was evaluated by means of synchronic measurements of the respiratory pattern (according to the assumption of Milic-Emili) and occlusion pressure P 0.1 (according to Whitlaw assumptions). In the examination performed directly after admission to the Unit the normal respiratory efficiency was noted in 24 persons. 12 persons (33.3%) suffered from the bronchi obturation. In the examination performed after hospitalisation and 9 days of total abstinence the normal ventilatory efficiency was found in 23 persons. In 13 of the patients (38.5%) respiratory obturation was still observed. After treatment in group of opiate abusers compared to control group values of respiratory resistance, occlusion pressure, minute ventilation and VT/T(in) index describing the activity of the central breathing regulation were increased, while the time of expiration and time of total breathing cycle were shorter.

Adult↗
PubMed2005

Effect of water-soluble metal working fluid aerosols on respiratory system after 13 weeks of repeated inhalation exposure in F344 rats.

Three groups of male F344 rats were exposed to a water-soluble metal working fluid (MWF) aerosol at concentrations of 20, 60 or 180 mg/m3 for 6 h/day, five days a week, for 13 weeks in inhalation chambers. The aerosol particles were normally distributed and the mass median aerodynamic diameter was 1.56 microm. Despite the absence of clinical findings or significant changes in body weight during the 13-week exposure period, the numbers of white blood cells and lung weights were significantly higher at the end of the 13-week exposure period. Exposure to 20 mg/m3 of the MWF aerosol was found to have an effect on the respiratory system, including an accumulation of foamy macrophages in the bronchoalveolar lavage (BAL) fluid and thickening of the alveolar walls in the histopathology. The level of histamine and number of polymorphonuclear (PMN) cells were also higher in the BAL fluid from the rats exposed to 60 mg/m3 of the MWF aerosol, while the respiratory inflammation was most pronounced in the rats exposed to 180 mg/m3 of the MWF aerosol, including the accumulation of PMNs and foamy macrophages in the BAL cells, lung weight increase and thickening of the alveolar walls. Immunoglobulin IgG2a level was also lower in the sera from the rats exposed to 180 mg/m3 of the MWF aerosol. Therefore, even though no clinical symptoms were observed in the rats exposed to the high MWF concentration, respiratory inflammation was still induced by a relatively low concentration of the MWF, while the immune system was affected by the high MWF concentration.

Administration, Inhalation↗
PubMed1990

[Effect of the work environment of the coke-processing industry on the respiratory system of coke factory workers].

The influence of the working environment in a coke factory on the respiratory system of workers was examined in 253 workers employed for at least 5 years at coke production in baking ovens, or at coke sorting and processing. They were exposed to high air concentrations of benzo(a)pyrene (BaP) and tar substances as well as other numerous toxic substances e.g. benzene++ derivatives, the level of which however, did not exceed the MAC values. Medical examination comprising the MRC questionnaire and spirometry , using Godart Expirograph, was carried out Among the exposed workers the non-specific chronic respiratory diseases with obstructive symptoms and chronic bronchitis were revealed more often than in the control group such factors as tobacco smoking and the duration of work also had their influence on the frequency of respiratory diseases. The possibility of the impact of high air concentrations of BaP and carbon monoxide cannot be excluded either.

Adult↗
PubMed1985

[Clinician-oriented and cytology-oriented autopsy, Part I. Respiratory system].

The autopsy is performed with multiple purposes. It is felt that the first purpose of the autopsy is a service for clinicians. Dissection technic should be determined to present the best clinical pathological correlation of the lesions. Touch preparation (imprint) from the organs is most useful to establish initial pathological diagnoses during autopsy examination. This provides not only oncologic data (identification of tumors), but also the presence of infectious complications such as opportunistic organisms. Multiple photographs illustrate both the gross pathological lesions and infections, demonstrated by the imprints of the respiratory system.

Autopsy↗
PubMed1992

Four-year follow-up of effects of toluene diisocyanate exposure on the respiratory system in polyurethane foam manufacturing workers. I. Study design and results of the first cross-sectional observation.

A 4-year cohort study was designed to assess the exposure-effect relationship of working in polyurethane foam (PF) manufacturing factories with exposure to toluene diisocyanate (TDI) and its effects on the respiratory system. This paper describes the results of the first cross-sectional observations. The study population included 90 male workers who had been working in PF factories for 0.5-25 years (mean 13.3 years) (PF workers) and 44 reference workers in the same factories. The mean exposure concentration of TDI calculated from 129 personal samples was 3.2 ppb. Peak exposure excursions above 20 ppb occurred in 16 of 129 samples. Pulmonary function and its change during the working day as assessed by examining the forced expiratory flow-volume curve, respiratory impedance, and airway resistance and specific airway conductance were not different in the PF workers from those in the reference workers. Chest X-radiographs did not show any noteworthy radiological changes. Prevalences of "phlegm in winter," "nasal stuffiness or discharge in winter," and "irritation of eye and throat mucous membranes" were significantly higher in the PF workers. The findings indicate that TDI exposure at levels around 3 ppb may not adversely affect the pulmonary function over many years of exposure of those who are not hypersensitive to TDI. The causal chemicals inducing some respiratory and irritative symptoms could not be specifically identified since the PF workers were exposed not only to TDI but also to other irritative agents in the PF manufacturing processes.

Adolescent↗
PubMed1976

A new method to determine frequency characteristics of the respiratory system.

A technique is described allowing one to determine simultaneously the resistance and reactance of the total respiratory system for various frequencies. During spontaneous breathing, regularly recurring impulses are produced at the mouth by means of a loud speaker. A Fourier analysis of the mouth pressure and flow signals yields mean resistance and reactance values, over 16 s, for all harmonics of 2 Hz up to 30 Hz. The values are in good agreement with those obtained in the absence of breathing and those determined by means of the forced oscillation technique and by body plethysmography. The reproducibility of the measurements is satisfactory (coefficient of variation: 11.6%).

Electronics↗
PubMed2005

[Spirometric evaluation of the respiratory system in adolescent swimmers].

MATERIAL AND METHODS: The influence of swim training on the function of the respiratory system was studied in girls and boys aged 10-18 years in whom a total of 1625 spirometries were done. Measurements included vital capacity, airflow in airways during expiration and inspiration, and maximum voluntary ventilation. Interpretation of the results was based on comparative analysis of age- and height-matched groups of girl/boy swimmers and sedentary controls. RESULTS: The effect of swim training on spirometric parameters with regard to anthropometric characteristics was investigated with the neural networks method. FVCEX and FEV1 correlated with height, arm span, and dimensions of the thorax. While airflow in airways during expiration was not affected by swimming, parameters defining inspiratory airflows were significantly higher in swimmers who trained regularly for 7-8 years. This finding appears to be due to the effect of training on inspiratory muscles. MVV followed FVCEX values in girl/boy swimmers and controls. CONCLUSION: The results demonstrate that vital capacity and airflow conditions in airways during expiration are not influenced by swim training.

Adolescent↗
PubMed1990

[Effects of negative extra-thoracic pressure ventilation on respiratory system and hemodynamics in normal dogs].

The effects of negative extra-thoracic pressure ventilation (NETPV) on respiratory system and hemodynamics were examined in ten normal dogs. Changes of the parameters obtained during intermittent NETPV (INETPV), and NETPV with negative end-expiratory pressure (CNETPV) were compared with those during IPPV and CPPV. Animals' chests and upper abdomens were confined in an acryl box. In INETPV and CNETPV, the dogs were ventilated with the negative extra-thoracic pressure ventilator (Kimura, OKT-100). Positive and negative pressure ventilation was carefully matched for tidal volume and the increase in FRC obtained with PEEP and the end-expiratory negative extra-thoracic pressure (EENETP). EENETP of -11.6 cmH2O produced the same FRC change as PEEP of 10.6 cmH2O did. Gas exchanges did not differ in any modes. INETPV did not change any hemodynamic parameters without PAP. In CNETPV, heart rate increased, and CVP, cardiac index (CI) and stroke volume (SV) decreased significantly (P less than 0.05), but tmCVP and tmPCWP did not change. The decreases of CI and SV (100----89.1, 88.8%) in CNETPV were significantly smaller when compared with CPPV (100----78.8, 74.5%). In CPPV, meanBP, CVP, tmCVP, tmPCWP, CI, SV changed significantly. The mechanisms of the decrease of CI and SV by CNETPV seemed to be different from those by CPPV.

Animals↗
PubMed2002

Respiratory system mechanics during laparoscopic cholecystectomy.

The influence of laparoscopic cholecystectomy (LC) on the mechanical properties of the respiratory system (RS) was examined using multiple regression analysis (MRA). Measurements of airway pressure (PaO) and flow (V') were obtained from 32 patients at four distinct stages of the LC procedure: 1) Immediately before the application of pneumoperitoneum (PP) at supine position, 2) 5 min after the induction of PP at Trendelenburg position, 3) 5 min after the patients position at reverse Trendelenburg, and 4) 5 min after the end ofthe surgical procedure with the patient again in supine position. Evaluated parameters were the RS elastance (Ers), resistance (Rrs), impedance (Zrs), the angle theta indicating the balance between the elastic and resistive components of the impedance, as well as the end-expiratory elastic recoil pressure (EEP). Ers and Zrs increased considerably during PP and remained elevated immediately after abolishing PP Rrs, on the contrary, returned to pre-operative levels right after the operation. Change of body position from Trendelenburg (T) to reverseTrendelenburg (rT) mainly induced a significant change in theta, thus indicating an increased dominance of the elastic component of Zrs on changing fromT to rT. There was no evidence of increased End-Expiratory Pressure during PP

Adolescent↗
PubMed1994

Mechanical behaviour of the canine respiratory system at very low lung volumes.

We studied the changes in dynamic elastance and resistance of the respiratory system in 6 supine, anaesthetized, paralysed, tracheostomised and open chested dogs. Tracheal pressure (Ptr), tracheal flow (V) and 3 alveolar pressures (Palv by alveolar capsule) were measured continuously for 20 min at 5 levels of positive end expiratory pressure (PEEP) between 0.1 and 0.5 kPa. The lungs were inflated to total lung capacity (TLC) at the start of each recording period. Lung elastance (EL) and resistance (RL) were estimated by fitting the equation Ptr = RLV + ELV + K to the measured data for each breath by multiple linear regression (V = volume, K = constant). Airway resistance (Raw) was obtained from the difference between Ptr and Palv. EL increased progressively in the 20 min following lung inflations. The increase in EL over this time was about 45% of its baseline value at a PEEP of 0.1 kPa compared to an increase of only about 10% at a PEEP of 0.5 kPa. In contrast, RL changed very little over the recording period at all levels of PEEP. At low levels of PEEP Palv often bore no resemblance to Ptr indicating that significant airway obstruction or closure had occurred. These results suggest that the increase in EL at low PEEP was primarily due to the accretion of airspace closure, and that nonlinear tissue mechanical properties were responsible for the lack of change in RL.

Airway Resistance↗
PubMed1996

[Respiratory system reactions to organic aerosol exposure].

The effects of organic aerosols (coffee, teas, spices, confectionery, soy, animal feed) on the respiratory system of workers occupationally exposed to these aerosols are presented. Described are possible mechanisms responsible for the development of respiratory impairment. Our studies indicate the possibility of development of respiratory impairment in exposed workers. The prevalence of chronic respiratory symptoms and diseases varied from 2.7 to 56.3% and of acute symptoms from 9.9 to 78.9% of exposed workers. Statistically significant acute reductions of ventilatory capacity (FVC, FEV1, FEF50, FEF25) were recorded during the work shift. Described are some immunological changes which can develop in exposure to organic aerosols. Experimental studies with water organic dust extracts on isolated guinea pig trachea suggest that bronchoconstrictive changes in humans may be reproduced in non-sensitized guinea pigs. The need for taking preventive medical examinations in order to prevent development of respiratory and/or immunological impairment is stressed.

Adult↗