Search Results
Results 751 - 800 of 1429
< 11 12 13 14 15 16 17 18 19 20 21 >
Ludwigs U - - 1995
STUDY OBJECTIVE: To compare volume-controlled inverse ratio ventilation (VCIRV) with volume-controlled ventilation with conventional inspiratory to expiratory (I:E) ratio (VCV PEEP) at equal levels of end-expiratory pressure. DESIGN: Animal study using an oleic acid lung injury model with random application of VCV PEEP and VCIRV. SETTING: Experimental investigation at the ...
Stenson B J - - 1995
Inadvertent positive end-expiratory pressure (PEEP) is a potential cause of lung overdistension and impaired gas exchange in ventilated infants. It can be extremely difficult to diagnose clinically and if unrecognized can be life-threatening. Measurement of lung function can lead to the recognition of inadvertent PEEP, allowing appropriate ventilator adjustment with ...
Pan P H - - 1995
The effects of positive end-expiratory pressure (PEEP) and lung compliance (CL) on delivered tidal volume (VTdel) and ventilator output were evaluated in the following anaesthesia machine/ventilator systems: Narkomed III with a Model AV-E ventilator (III/AV-E system) and an Ohmeda Modulus II with either a 7810 anaesthesia ventilator (II/7810 system) or ...
Pelosi P - - 1995
In 16 mechanically ventilated patients with acute lung injury (ALI) (eight patients with moderate ALI [moderate group], eight patients with severe ALI [adult respiratory distress syndrome, ARDS group]) and in eight normal anesthetized-paralyzed subjects (control group), we partitioned the total respiratory system mechanics into the lung (L) and chest wall ...
Brienza N - - 1995
Total venous return decreases with positive end-expiratory pressure (PEEP). It is likely that the liver plays an important role in this response, either through the development of an increase in venous resistance or through an increase in the venous backpressure at the outflow end of the liver. In addition, hepatic ...
Love R - - 1995
Positive end-expiratory pressure (PEEP) is a commonly used adjunct to mechanical ventilation and is known to have deleterious effects on cardiac output (CO). Its effects on regional blood flow are not well known. We evaluated the effect of PEEP on the mesenteric microcirculation and CO. Sprague-Dawley rats were treated with ...
Brunet F - - 1995
This study was aimed at providing data for optimization of mechanical ventilation in patients with acute respiratory distress syndrome (ARDS). The effects of ventilation with positive end-expiratory pressure (PEEP) titrated to blood gases were studied by thoracic computed tomographic (CT) scans and lung mechanics measurements in eight patients. CT density ...
Kelly S M - - 1995
The mechanism by which Xenopus laevis oocytes and eggs survive in hypotonic media was investigated by measuring cell volume (Vc) and intracellular pressure (P(ic)) during osmotic swelling. After 2 hr in 10 mOsm buffer, eggs remained intact, while 60.2 +/- 7.0% of oocytes had burst. Water uptake was proportional to ...
Suzuki Y - - 1995
We studied the mechanisms by which pulmonary solute clearance is affected by lung inflation. We examined the pulmonary clearance of inhaled technetium-99m diethylenetriaminepentaacetic acid (99mTc-DTPA) together with changes in lung volumes in healthy men after applying graded levels of continuous external negative pressure (CNP) and positive end-expiratory pressure (PEEP). The ...
Jacob L P - - 1995
Increased intrathoracic pressure with positive pressure breathing (PPB) induces renal hypoperfusion and excretion function impairment the mechanism of which may be partially related to reflex sympathetic nerve activation. The consequences of renal denervation on PPB-induced renal impairment are unknown. This study was conducted to evaluate the effects of increasing intrathoracic ...
Puybasset L - - 1995
The aim of this prospective study was to determine factors influencing effects of inhaled nitric oxide (NO) on the pulmonary circulation and on gas exchange in critically ill patients with acute lung injury. Twenty-one hypoxemic patients with acute respiratory failure (PaO2 = 127 +/- 69 mm Hg during intermittent positive ...
Patel H - - 1995
OBJECTIVE: Since variations in breathing pattern may affect the level of intrinsic positive end-expiratory pressure (PEEP), breath-to-breath variation of intrinsic PEEP was assessed. DESIGN: Descriptive and prospective study. SETTING: Medical intensive care unit of a university teaching hospital. PATIENTS: Thirty-four patients requiring mechanical ventilation for a period of time due ...
Barbato A - - 1995
Very little is known as yet about the effect of salmeterol in pediatric asthma, so a trial was performed on children with mild asthma to compare salmeterol with salbutamol in terms of how quickly they took effect. The double-blind study involved 11 children (mean age 13.4 years) randomly assigned to ...
Buckman R F RF Jr Department of Surgery, Temple University Health Science Center, Philadelphia, PA 19140, - - 1995
Open-chest cardiac massage (OC-CM) provides higher blood pressure and flow than closed-chest compression and may improve the probability of successful resuscitation from cardiac arrest. Its clinical use has been limited by its requirement for a major thoracotomy. The present pilot study tested the technical feasibility of performing effective direct cardiac ...
Gattinoni L - - 1995
The distribution of tidal volume (VT) and recruitment was investigated by chest computed tomography (CT) in eight sedated-paralyzed patients with the adult respiratory distress syndrome (ARDS). A CT section was obtained in the supine position at 0, 5, 10, 15, and 20 cm H2O positive end-expiratory pressure (PEEP) and at ...
Fessler HE - - 1995
Continuous positive airway pressure, like positive end-expiratory pressure (PEEP), increases lung volume and pleural pressure and usually decreases venous return. The decrease in venous return has been ascribed to a simple increase in right atrial pressure. However, recent studies have demonstrated PEEP also changes the resistive and elastic properties of ...
Conzemius M G - - 1995
Intra-abdominal pressure (IAP) was indirectly measured, using a transurethral catheterization technique, in 20 client-owned dogs before and after elective ovariohysterectomy. Mean preoperative IAP was 4.50 +/- 0.44 cm H2O. Elective abdominal surgery caused significant elevations in mean postoperative IAP (mean 7.50 +/- 0.45 cm H2O, range 0 to 15 cm ...
Christensen E F - - 1995
Valves for positive expiratory pressure (PEP) can be characterized as threshold resistors, ideally providing pressure independent of the expiratory flow, or as flow-dependent resistors. The aim of the study was to evaluate the flow-dependence properties of PEP devices of the flow resistor type compared to threshold resistor devices. Pressures were ...
Farge D - - 1995
The interactions between hemodynamic and hormonal modifications during antidiuresis and antinatriuresis induced by positive end-expiratory pressure (PEEP) were studied in six patients under 15 cm H2O PEEP before PEEP and after the addition of lower body positive pressure (LBPP) to PEEP (PEEP+LBPP). We measured or calculated the following: cardiac index, ...
Persson M G - - 1995
BACKGROUND: Nitric oxide (NO) formed from L-arginine is exhaled by mammals and regulates pulmonary vascular tone. Little is known about how its formation is stimulated. METHODS: The concentration of NO in exhaled air was monitored by chemiluminescence in pentobarbital-anesthetized rabbits receiving mechanical ventilation by tracheostomy with graded positive end-expiratory pressure ...
Trigo-Rocha F - - 1995
Cavernous smooth muscle relaxation is effected through a complex biochemical pathway; therefore, a defect in any step of this pathway may result in erectile dysfunction. Administration of pharmacologic agents which cause relaxation of the cavernous smooth muscle through a different mechanism may serve as an effective therapeutic alternative for impotent ...
Easa D - - 1995
Little attention has been focused on the progressive pulmonary deterioration which occurs in mechanically ventilated infants with normal or mildly abnormal lungs. We hypothesized that lung function would deteriorate over a 24-hr period in anesthetized neonatal piglets with normal lungs mechanically ventilated at 2 cm H2O PEEP (2PEEP group). We ...
Chang S O - - 1995
We used the IL088 Otodynamic Analyzer system to study click-evoked otoacoustic emissions (CEOAEs) in 30 healthy guinea pigs. The animals were anesthetized and patterns of the CEOAEs were evaluated before manipution, after the tympanic bulla was opened, and after formation of a microfistula on the basal turn of the cochlea. ...
Mang H - - 1995
Numerous approaches to the provision of mechanical ventilation during acute lung injury are currently available. Of these, pressure control inverse ratio ventilation has been considered superior to volume control ventilation with PEEP with respect to improving gas exchange and minimizing cardiovascular compromise. However, no study systematically compares volume-controlled (VC) and ...
Curiel C - - 1995
The influence of cardiac output (CO) and PEEP on pulmonary shunt (Qs/Qt) has been the subjects of considerable investigation but findings are controversial. The role of CO and PEEP on 19 isolated rabbit lung preparations perfused with hypoxic mixture (6% CO2, 10% O2, and 84% N2), which resulted in a ...
Lessard M R - - 1995
Intrinsic positive end-expiratory pressure (PEEPi) has usually been interpreted as suggesting dynamic hyperinflation, but expiratory muscle activity may also increase end-expiratory alveolar pressure without any additional increase in end-expiratory lung volume. The aim of this study was to assess the influence of expiratory muscle activity, which increases abdominal pressure during ...
Armstrong B W BW - - 1995
OBJECTIVES: To investigate physiologic and outcome data in patients switched from volume-cycled conventional ratio ventilation to pressure-controlled inverse ratio ventilation that did not produce air trapping and intrinsic positive end-expiratory pressure (PEEP). SETTING: Medical intensive care unit. DESIGN: Retrospective analysis of crossover data and outcome. PATIENTS: Fourteen patients with the ...
Woolley D S - - 1995
Laparoscopy is used increasingly in managing critically ill patients. Carbon dioxide (CO2) pneumoperitoneum is used during these procedures. The increased intra-abdominal pressure of CO2 pneumoperitoneum, however, can affect cardiopulmonary performance adversely. Recently, gasless abdominal wall distention has been introduced as an alternative to CO2 pneumoperitoneum. The purpose of this study ...
Mundie T G - - 1995
Recent clinical studies have suggested that improvement in pulmonary gas exchange with the use of continuous negative extrathoracic pressure (CNEP) in conjunction with intermittent mandatory ventilation (IMV) may be due to increased pulmonary blood flow. Accordingly, we investigated the effects of CNEP vs positive end-expiratory pressure (PEEP) in ventilated neonatal ...
Aufricht C - - 1995
The shape of the volume-pressure (V/P) curve indicates alveolar collapse if it is convex to the pressure axis and indicates overdistension if it is concave. Positive end-expiratory pressure (PEEP) should either improve or decrease compliance and oxygenation in neonates ventilated for respiratory distress syndrome (RDS), depending on predominance of either ...
Klow N E - - 1995
Patient safety should be in focus when using contrast media (CM) in diagnostic and interventional cardiac procedures. Side-effects that occur during cardioangiography due to hemodynamic effects of CM include direct effects on the heart, effects on the systemic and pulmonary circulation, and effects on the blood volume. Although not a ...
Meyer P G - - 1994
We studied 60 children undergoing neurosurgical procedures in the sitting position. Routine monitoring included ECG, pulse oximetry, invasive arterial pressure, in particular mean arterial pressure (MAP), and right atrial pressure (RAP). Children were allocated to two groups. In group B lower body positive pressure and positive end-expiratory pressure (PEEP) were ...
Maltais F - - 1994
The incidence and severity of bronchial asthma has increased considerably in recent years. As a result, the number of patients requiring mechanical ventilation and more intensive medical therapy for treatment of refractory asthma has also increased. Despite this, available information concerning the quantitative changes in respiratory mechanics and the response ...
Maltais F - - 1994
Intrinsic positive end-expiratory pressure (PEEPi) is routinely determined under static conditions by occluding the airway at end-expiration (PEEPi,stat), the resulting plateau pressure representing the average PEEPi present within a nonhomogeneous lung. In contrast, PEEPi can also be evaluated dynamically (PEEPi,dyn) by recording the change in pressure required to initiate lung ...
Kaczmarczyk G - - 1994
Controlled mechanical ventilation with positive end-expiratory pressure (PEEP) is generally associated with decreases in urine volume and renal sodium excretion. The resulting positive sodium and water balance is an undesirable side effect of controlled mechanical ventilation with PEEP. The increase in intrathoracic pressure initiates a cascade of hemodynamic, neural, and ...
Kesecioglu J - - 1994
The purpose of this study was to evaluate whether any benefit of low frequency positive pressure ventilation with extracorporeal carbon dioxide removal (LFPPV-ECCO2R) existed over either volume controlled ventilation (VCV) with measured best-PEEP or pressure regulated volume controlled ventilation (PRVCV) with an inspiration/expiration (I/E) ratio of 4:1, with respect to ...
Baigorri F - - 1994
OBJECTIVE: To study the effect of positive end-expiratory pressure (PEEP) on right ventricular hemodynamics and ejection fraction in patients with chronic obstructive pulmonary disease and positive alveolar pressure throughout expiration by dynamic hyperinflation (auto-PEEP). DESIGN: Open, prospective, controlled trial. SETTING: General intensive care unit of a community hospital. PATIENTS: Ten ...
Storme L - - 1994
We have previously described a passive inflation method during constant inspiratory flow for measuring total respiratory elastance and resistance during mechanical ventilation in newborns. The simple method for measuring respiratory mechanics had been assessed during decelerating inspiratory flow obtained with pressure controlled ventilation (PCV). We report an application of this ...
Martinez F J - - 1994
OBJECTIVES: To examine a hygroscopic condenser after clinical use and to describe the interaction of a hygroscopic condenser and a closed circuit suction system used simultaneously. DESIGN: Prospective evaluation of hygroscopic condensers used clinically, and laboratory investigation of a hygroscopic condenser used with a closed circuit suction system. SETTING: Tertiary ...
Chandra A - - 1994
The effectiveness of positive end-expiratory pressure (PEEP) relates directly to alveolar recruitment. We tested the hypothesis that active use of expiratory muscles during labored breathing impairs the ability of PEEP to increase end-expiratory lung volume. Eight healthy volunteers naive to the purposes of our study were exposed to targeted end-expiratory ...
Waddell T K - - 1994
Exposure of animals to transient hyperthermia causes the induction of highly conserved proteins, heat shock proteins (HSPs), which are thought to by cytoprotective against a variety of injuries, including ischemia. We tested the hypothesis that heating donor animals prior to harvest would improve pulmonary preservation. Anaesthetized New Zealand White rabbits ...
Roithmaier A - - 1994
OBJECTIVES: Evaluation of a modified, computer-controlled, shutter method to determine the complete intrapulmonary pressure course and to ascertain the expiratory time constant for the respiratory system during high-frequency positive pressure ventilation. DESIGN: Prospective clinical study. SETTING: Neonatal intensive care unit in a university hospital. PATIENTS: Sixteen premature newborns (mean gestational ...
Moens Y - - 1994
Effects of differential ventilation on gas exchange were studied in 7 isoflurane-anesthetized, laterally recumbent horses, and were compared with effects of conventional ventilation, using similar minute volume. A tracheal tube-in-tube intubation technique allowed each lung to be connected separately to an anesthetic circle system with a ventilator. Two distribution patterns ...
Ludwigs U - - 1994
STUDY OBJECTIVE: To compare volume-controlled ventilation (VCV PEEP) with pressure-controlled inverse ratio ventilation (PCIRV) at equal levels of end-expiratory pressure. DESIGN: Animal study using an oleic acid lung injury model with random application of VCV PEEP and PCIRV. SETTING: Experimental laboratory investigation at the Department of Clinical Physiology at Uppsala ...
Blanch L - - 1994
PURPOSE: To study the effect of two tidal volumes on gas exchange, lung mechanics, and hemodynamics in 12 patients with acute respiratory distress syndrome (ARDS) within the first 72 hours of mechanical ventilation. METHODS: Tidal volume (VT) was increased by 40% from the initial value at fixed positive end-expiratory pressure ...
Ermakov S V - - 1994
For a rigorous assessment of the precise amount of sample loaded, for quantitation purposes, different sample injection systems were evaluated with two commercially available units, Waters Quanta 4000 and Beckman P/ACE 2100. In the first system, sample introduction by hydrostatic means (i.e., placing the sample vial at some height, usually ...
Cros A M - - 1994
This experimental study was carried out to determine if an alveolar positive end-expiratory pressure (PEEP) could occur during high frequency jet ventilation (HFJV) in infants, and if tracheal pressure is a good estimation of alveolar pressure. We used physical models simulating a 1.5 kg premature (P), a 3 kg newborn ...
Mancini P - - 1994
Extracorporeal life support (ECLS) is a recognized treatment for neonatal respiratory distress unresponsive to other forms of therapy. Variations of this technique are being developed in an effort to extend its applicability and safety. Extracorporeal CO2 removal (ECCO2R) is one such modification that requires blood flows of 20% to 50% ...
Poelaert J I - - 1994
Positive-pressure ventilation has often been advocated to increase oxygen delivery. This ventilation mode itself, however, can impair right ventricular ejection and, thus, diminish cardiac output. In this study, alterations of right ventricular outflow impedance were evaluated after stepwise increases of positive end-expiratory pressure (PEEP). Different pulmonary artery flow characteristics were ...
Houpt T R - - 1994
Pressures were measured with miniature transducers positioned within the gastric lumen of six young pigs, 20-40 kg, eating and drinking operantly. The pigs were free to move about, lie down, sleep, eat, and drink without disturbance. 1) At the end of 4-5-h fasts (with no drinking), mean pressure within the ...
< 11 12 13 14 15 16 17 18 19 20 21 >