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Results 351 - 400 of 589
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Thomas A N - - 1992
A method of bag valve mask ventilation (BVM) in which the resuscitator compresses the self-inflating bag between the open palm and body was compared with both standard single resuscitator and two-resuscitator BVM ventilation. Eighteen subjects ventilated a modified recording manikin using each method in random order. The tidal volume (VT) ...
Bengtson J P - - 1992
The uptake of enflurane and of isoflurane were studied in forty patients during anaesthesia with nitrous oxide using either spontaneous or controlled ventilation. A Douglas bag method was used in combination with low fresh gas flows to a circle system and constant end-tidal anaesthetic concentration. The mean enflurane uptake rates ...
Harrison G A - - 1992
A case study is reported of a subject who has used inspiratory speech (IS) for 6 years as a means of overcoming the communication problems of long-standing adductor spastic dysphonia (ASD). The subject was studied to confirm his use of IS, determine the mechanisms of its production, investigate its effects ...
Schaffartzik W - - 1992
Ventilation-perfusion (VA/Q) inequality has been shown to increase with exercise. Potential mechanisms for this increase include nonuniform pulmonary vasoconstriction, ventilatory time constant inequality, reduced large airway gas mixing, and development of interstitial pulmonary edema. We hypothesized that persistence of VA/Q mismatch after ventilation and cardiac output subside during recovery would ...
Browning D - - 1992
A 20-year-old woman in status asthmaticus who failed to respond to conventional therapy and ventilation of the lungs with 0.5-2.0% halothane, was cooled to 30 degrees C for almost 5 days as the arterial carbon dioxide tension rose above 15 kPa. Halothane was not of immediate value, contrary to other ...
Cross S J - - 1992
1. In six healthy subjects the amplitude and phase of respiratory sinus arrhythmia were determined at five different respiratory cycle lengths ranging from 3 to 9.5 s. 2. At each respiratory cycle length the carotid baroreceptor-heart rate reflex response was determined by cyclical neck suction at -40 mmHg at five ...
Vaz Fragoso C A - - 1992
Progressive neuromuscular symptoms years after recovery from acute paralytic poliomyelitis have been termed the PPS. We describe a 52-year-old man who contracted poliomyelitis at age 9 years who fully recovered and 33 years later developed progressive dyspnea. Neurologic evaluation revealed bilateral paralysis of the vocal cords, generalized weakness, and accentuated ...
Kelsey C J - - 1992
These experiments examined the changes in ventilation during a 40-s ramp increase in exercise load, produced by increasing either the speed of the treadmill or the grade, to equivalent end-points of oxygen uptake. Six subjects underwent five trials each for grade and speed, while ventilation was monitored breath-by-breath. For each ...
Tulla H - - 1992
We studied the effects of elective hip surgery, performed under either spinal (SA, n = 10) or general anesthesia (GA, n = 10), on breathing pattern and gas exchange. Measurements were made with respiratory inductive plethysmograph and indirect calorimetry in two positions before and after surgery. The method of anesthesia ...
Webb P I - - 1992
Mean oxygen consumption and simultaneous ventilation frequency of nine non-reproductive brown long-eared bats (body mass 8.53-13.33 g) were measured on 159 occasions. Ambient (chamber) temperature at which the measurements were made ranged from 10.8 to 41.1 degrees C. Apneic ventilation occurred in 22 of the 59 measurements made when mean ...
Boutellier U - - 1992
The present study was undertaken to investigate the respiratory system as an exercise limiting factor. Breathing and cycle endurance (i.e. the time until exhaustion at a given performance level) as well as physical working capacity 170 (i.e. the exercise intensity corresponding to a heart rate of 170 beats.min-1 on a ...
Derion T - - 1992
Water immersion can cause airways closure during tidal breathing, and his may result in areas of low ventilation-perfusion (VA/Q) ratios (VA/Q less than or equal to 0.1) and/or shunt and, ultimately, hypoxemia. We studied this in 12 normal males: 6 young (Y; aged 20-29 yr) with closing volume (CV) less ...
Hurewitz A N - - 1991
We have previously shown that airway insufflation (AI) reduces dead space (VD) and minute ventilation (VL) in patients with respiratory failure, and when used chronically leads to lowered and more stable arterial PCO2. The present study was designed to measure the effect of increasing AI flow rate on VD and ...
Hess D - - 1991
Noninvasive monitoring is commonly used during ventilatory support. This monitoring includes pulse oximetry, capnography, transcutaneous monitoring, monitoring of respiratory mechanics, and indirect calorimetry. There are advantages and disadvantages to each of these forms of monitoring and the technical ability to use each of them must be balanced against clinical usefulness.
Fleming H - - 1991
Several different stimuli, including hydrogen ions, may exert their effect on central ventilatory control through cholinergic mechanisms. Salicylates are known to be central respiratory stimulants. Therefore this study explored whether the ventilatory effect of sodium salicylate (SAL) is through cholinergic mechanisms. Ventriculocisternal perfusion was used in spontaneously breathing anesthetized (pentobarbital ...
Papazoglou N - - 1991
A comparison of the respiratory responses of jogging in place, an alternative exercise test we recently proposed, was made with those of the Bruce exercise test. We obtained on-line measurements of heart rate, ventilation, oxygen uptake, and carbon dioxide production from 9 healthy subjects of mean age 25 years. There ...
Kiiski R - - 1991
OBJECTIVE: To validate the assessment of changes in alveolar ventilation and deadspace by indirect calorimetry. DESIGN: An open comparison of two methods using a criterion standard. METHODS: Simultaneous measurement of minute ventilation with a metabolic monitor and a pneumotachometer during controlled and synchronized intermittent mandatory ventilation in intensive care patients ...
Dunn W F - - 1991
We investigated the mechanisms responsible for oxygen-induced hypercarbia in ventilator-dependent patients with advanced chronic obstructive pulmonary disease (COPD). To quantitate the effects of oxygen (O2) on respiratory drive, we determined the CO2 recruitment threshold (PCO2 RT) in 10 mechanically ventilated patients under normoxic (PaO2 = 67 +/- 7 mm Hg) ...
Whitfield J B - - 1991
The effect of humidity on the histologic lesions induced by high-frequency jet ventilation was investigated in 12 healthy cats. After 16 hours of ventilation, the appearance of the tracheal epithelium ranged from normal to necrotic. The damage was considerably more severe in the trachea of cats of the group ventilated ...
Blackie S P - - 1991
Assessment of the breathing pattern at maximal exercise in patients is limited because the range of ventilatory responses (minute ventilation; tidal volume; respiratory rate) at maximal exercise in normal humans is unknown. We studied 231 normal subjects (120 women; 111 men) equally distributed according to age from 20 to 80 ...
Ravenscraft S A - - 1991
OBJECTIVE: To determine the causes of excess minute ventilation in patients initiated on mechanical ventilation. DESIGN: Prospective study of recently intubated, mechanically ventilated patients. SETTING: The medical ICU in a county hospital. PATIENTS: Fifty-two mechanically ventilated medical ICU patients were studied within 36 hrs of intubation. Patients were all supported ...
Greenslade G L - - 1991
Cardiopulmonary resuscitation en route to hospital is performed by a single-handed operator in many British ambulances. In this study, three emergency ventilation devices, and mouth-to-mouth breathing, were compared for effectiveness in unintubated patients. Seventeen paramedics used each method on a Laerdal manikin in a randomised order, under identical conditions. Three ...
Jaeger M J - - 1991
Dogs were ventilated with a high-frequency oscillation device varying the frequency (5-15 Hz), the tidal volume (25-100 ml), and the resident gas (He, N2, SF6). Tidal volume was measured with a body plethysmograph. Blood gases were measured after a quasi-steady state was established. The kinematic viscosity of the breathing gas ...
Wilson R C - - 1991
1. The intensity of breathlessness in normal subjects during exercise was measured on seven occasions over a 40-week study period to assess the long-term repeatability of Borg scale estimates of breathlessness. 2. In all subjects there was a significant correlation (P = 0.0001) between breathlessness and minute ventilation. Minute ventilation ...
Art T - - 1991
In order to facilitate lung auscultation, a transitory hyperpnea may be obtained by lobeline administration, use of a rebreathing bag or exercise. The effect of these three methods on the pulmonary function were studied and compared in 5 healthy ponies. Respiratory airflow and tidal volume were measured with a pneumotachograph ...
Meyer J - - 1991
The effects of high frequency jet ventilation (HFJV, f = 2 Hz and 8 Hz, I:E = 0.43, FiO2 = 0.4) were studied and compared with intermittent positive pressure ventilation (IPPV, f = 10-14 breaths/min, VT = 15 ml/kg, I:E = 0.5, FiO2 = 0.4) in 8 dogs before and ...
Rutledge G - - 1991
VentPlan assists physicians, nurses, and respiratory therapists in the management of artificial respiration for critically ill patients in the intensive-care unit (ICU). VentPlan interprets clinical observations, monitored data, and arterial-blood-gas analyses to make recommendations for setting the ventilator. The VentPlan interface allows users to examine the physiologic model, to inspect ...
Basti J J - - 1991
Status asthmaticus (SA) is a life-threatening exacerbation of asthma that is refractory to usual therapeutic interventions. The etiologic factors leading to SA and pathophysiologic alterations in airway caliber, respiratory muscle function, and respiratory gas exchange are reviewed. Important parameters in the assessment of patients presenting with SA are highlighted, including ...
Wilson R C - - 1991
1. This study was designed to examine whether normal subjects could differentiate between the 'intensity' of their breathlessness and the amount of 'distress' it evoked, by specific wording of the instructions. 2. A preliminary study showed no significant difference between 'distress' score during exercise measured on two separate occasions (P ...
Bucher T L - - 1990
Although both energy metabolism and ventilation parameters are highly size dependent in adult birds, the usual scaling relationships with mass do not hold in hatchlings or in growing chicks. In Adélie penguins, three distinct behavioral phases during growth and development are reflected in the ontogeny of metabolism and ventilation. Metabolic ...
Kanter R K - - 1990
In order to evaluate the impact of simulation complexity on resuscitation skill performance, 15 pediatric residents were observed in bag-valve-mask ventilation on an infant manikin. Performance was evaluated in a simple exercise in which ventilation was performed as a single isolated task. For each subject, this was compared to performance ...
Waisbren S J - - 1990
This study was undertaken to determine if the observed increase in ventilation during passive limb movement was a reflex hyperventilation or a response to an increased metabolic need for oxygen. Experiments on human volunteers were designed to test the hypothesis that the rapid increase of ventilation at the onset of ...
Cotes J E - - 1990
A rating procedure for respiratory disability has been developed; it entails measuring the symptom-limited maximal oxygen uptake or estimating the maximal uptake from the results of a submaximal exercise test and other relevant variables. The derivation assumes a linear scale of disability between the limits 0% and 100% which are ...
Witta K - - 1990
This article compares the weaning of challenging patients from mechanical ventilation to an exercise training program experienced by many athletes. Physically, the importance of the correction and maintenance of chronic health issues, nutrition, and hydration are explored. Psychologically, the degree of preparedness by both the patient and the health care ...
Nagase T - - 1990
The effects of high frequency oscillatory ventilation (HFOV) and conventional mechanical ventilation (CMV) on tracheal secretion were compared in 6 anesthetized dogs. Using a double-balloon endotracheal catheter, 5 ml of saline was instilled into an isolated tracheal segment during HFOV and CMV for 10 min respectively. Two eicosanoids, 15-hydroxyeicosatetraenoic acid ...
Toyooka H - - 1990
Effect of high frequency jet ventilation (HJFV) on tracheobronchial tone was examined in anesthetized dogs. Changes in intraluminal pressure of water-filled endotracheal cuff (Pcuff) were used as an indicator of tracheal smooth muscle tone. Animals were initially ventilated with conventional mechanical ventilation (CMV) to maintain normal Pa(CO)(2). HFJV (2.0 Hz.) ...
Venegas J G - - 1990
The effects of body position and respiratory frequency (f) on regional gas transport during eucapnic conventional ventilation (CV) and high-frequency ventilation (HFV) were assessed from the washout of nitrogen 13 (13NN) using positron-emission tomography. In one protocol, six dogs were ventilated with CV or HFV at f = 6 Hz ...
Tsukimoto K - - 1990
Several previous studies have shown worsening ventilation-perfusion (VA/Q) relationships in humans during heavy exercise at sea level. However, the mechanism of this deterioration remains unclear because of the correlation with ventilatory and circulatory variables. Our hypothesis was that the decrease in the series dead space-to-tidal volume ratio during exercise might ...
Thompson-Gorman S L - - 1990
The purpose of the present study was to compare the relative roles of PaCO2 and pulmonary mechanoreceptors in the generation of apnea during high frequency ventilation (HFV) and conventional mechanical ventilation (CMV) in the anesthetized cat. Our hypothesis was that PaCO2 primarily determines the appearance of apnea, while mechanoreceptor input ...
Chonan T - - 1990
To determine whether the intensity of dyspnea at a given level of respiratory motor output depends on the nature of the stimulus to ventilation, we compared the sensation of difficulty in breathing during progressive hypercapnia (HC) induced by rebreathing, during incremental exercise (E) on a cycle ergometer, and during isocapnic ...
Bark H - - 1990
An experimental study to elucidate the physiological changes that occur in respiration during near drowning in the Dead Sea was performed in an experimental model. Findings showed that clinical signs of respiratory failure were due to aspiration rather than ingestion of Dead Sea water and occurred within 10 min of ...
Bourgain J L - - 1990
To improve ventilation monitoring during direct laryngoscopy, we have developed a high frequency jet ventilator which allows the aspiration of tracheal gas for carbon dioxide analysis (PtCO2) through the injector after stopping the ventilator. In 41 patients undergoing direct laryngoscopy, PaCO2 and PtCO2 were measured simultaneously during high frequency jet ...
Shikora S A - - 1990
During the course of a critical illness, many patients become ventilator dependent. The standard assessment criteria are not always accurate in predicting potential for extubation. This investigation was designed to analyze whether the work of breathing (WOB) was a more reliable predictor of ventilator dependence. Twenty consecutive ventilator-dependent patients were ...
Modi N - - 1990
The relationship between sodium handling and alveolar-arterial oxygen gradient (AaDO2) was studied in 26 preterm babies requiring ventilation from birth. The difference between sodium intake and urinary sodium excretion was determined in sequential, four hourly periods throughout the course of the respiratory illness. Sodium retention changed from positive (mean 1.42 ...
Gerdes J S - - 1990
Surfactant protein-A (SP-A) was measured in bronchoalveolar lavage (BAL) samples from ventilated neonates in order to study the concentration of SP-A with regard to: 1) high-frequency oscillatory ventilation (HFOV) vs. conventional mechanical ventilation (CMV); 2) the postnatal course and ontogeny of SP-A; and 3) the correlation with measurements of pulmonary ...
Torres A - - 1989
Using the multiple inert gas elimination technique, we studied ventilation-perfusion (VA/Q) relationships in eight patients with chronic obstructive pulmonary disease (COPD) during mechanical ventilation (MV) and again during weaning (spontaneous ventilation [SV] through an endotracheal tube) from MV needed for acute respiratory failure. The patients, seven men and one woman ...
Lee L N - - 1989
Patients with asthma frequently show a bimodal distribution of ventilation-perfusion (VA/Q) ratios. One mode is centered on a VA/Q ratio of near normal value, whereas the other has a very low VA/Q ratio. There is usually almost no perfusion of unventilated units. We have suggested that this bimodal pattern is ...
Anholm J D - - 1989
Although impaired respiratory muscle performance that persists up to 5 min after exercise is stopped has been demonstrated during exhaustive exercise in normal young men, it is not known whether impaired respiratory muscle function follows endurance exercise to exhaustion in highly trained athletes. To study the effects of exercise on ...
Brown D D - - 1989
T'ai Chi Chuan (TCC) is a widely practiced Chinese martial art said to physically develop balance and coordination as well as enhance emotional and mental health. TCC consists of a series of postures combined into a sequential movement providing a smooth, continuous, low-intensity activity. The purpose of this study was ...
Goldstein S A - - 1989
Eight malnourished patients with emphysema (EMPH) and eight malnourished patients without evidence of lung disease (MLAN) received an infusion of 5% dextrose plus electrolytes (D5W) for 48 h and were then randomly assigned to a hypercaloric diet with either 53% of the calories as carbohydrate (CB) or with 55% as ...
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