Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: UMLS:C0476273 (respiratory distress)
19,632 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The prophylactic effects of selectin inhibitors on lipopolysaccharide-induced acute lung injury were studied in rabbits by using sialyl Lewis X-oligosaccharide and PB1.3, an anti-human P-selectin monoclonal antibody. Lipopolysaccharide-induced acute lung injury resembles that of the acute respiratory distress syndrome, in which there is a decrease in arterial blood oxygen tension (PaO2) and an increase in the difference between alveolar and arterial oxygen tension (A-aDO2). Prophylactic treatment with the selectin inhibitors, sialyl Lewis X-oligosaccharide (55 mg kg(-1) i.v. bolus injection immediately before lipopolysaccharide administration + 36 mg kg(-1) h(-1) i.v. infusion for 4 h) and PB1.3 (5 mg kg(-1) i.v. bolus injection immediately before lipopolysaccharide administration), prevented the lipopolysaccharide-induced impairments in pulmonary gas exchange. In contrast, these agents had no significant effects on lipopolysaccharide-induced systemic hypotension, the decrease in the number of circulating white blood cells and platelets, the decline in blood pH, or the increase in arterial CO2 tension (PaCO2). These results indicate that selectin inhibitors including sialyl Lewis X-oligosaccharide and the anti-P-selectin antibody, PB1.3, attenuate lipopolysaccharide-induced acute lung injury in rabbits. This is the first demonstration that P-selectin is directly involved in the development of lipopolysaccharide-induced impairments in pulmonary gas exchange.
...
PMID:Protective effects of sialyl Lewis X and anti-P-selectin antibody against lipopolysaccharide-induced acute lung injury in rabbits. 1032 79

The aim of this study was to compare three ventilatory techniques for reducing PaCO2 in patients with severe acute respiratory distress syndrome treated with permissive hypercapnia: (1) expiratory washout alone at a flow of 15 L/min, (2) optimized mechanical ventilation defined as an increase in the respiratory frequency to the maximal rate possible without development of intrinsic positive end- expiratory pressure (PEEP) combined with a reduction of the instrumental dead space, and (3) the combination of both methods. Tidal volume was set according to the pressure-volume curve in order to obtain an inspiratory plateau airway pressure equal to the upper inflection point minus 2 cm H2O after setting the PEEP at 2 cm H2O above the lower inflection point and was kept constant throughout the study. The three modalities were compared at the same inspiratory plateau airway pressure through an adjustment of the extrinsic PEEP. During conventional mechanical ventilation using a respiratory frequency of 18 breaths/min, respiratory acidosis (PaCO2 = 84 +/- 24 mm Hg and pH = 7.21 +/- 0.12) was observed. Expiratory washout and optimized mechanical ventilation (respiratory frequency of 30 +/- 4 breaths/min) had similar effects on CO2 elimination (DeltaPaCO2 = -28 +/- 11% versus -27 +/- 12%). A further decrease in PaCO2 was observed when both methods were combined (DeltaPaCO2 = -46 +/- 7%). Extrinsic PEEP had to be reduced by 5.3 +/- 2.1 cm H2O during expiratory washout and by 7.3 +/- 1.3 cm H2O during the combination of the two modes, whereas it remained unchanged during optimized mechanical ventilation alone. In conclusion, increasing respiratory rate and reducing instrumental dead space during conventional mechanical ventilation is as efficient as expiratory washout to reduce PaCO2 in patients with severe ARDS and permissive hypercapnia. When used in combination, both techniques have additive effects and result in PaCO2 levels close to normal values.
...
PMID:Expiratory washout versus optimization of mechanical ventilation during permissive hypercapnia in patients with severe acute respiratory distress syndrome. 1039 Mar 83

The aim of the study was to analyse the effects of positive end-expiratory pressure (PEEP) on volumetric capnography and respiratory system mechanics in mechanically ventilated patients. Eight normal subjects (control group), nine patients with moderate acute lung injury (ALI group) and eight patients with acute respiratory distress syndrome (ARDS group) were studied. Respiratory system mechanics, alveolar ejection volume as a fraction of tidal volume (VAE/VT), phase III slopes of expired CO2 beyond VAE and Bohr's dead space (VD/VT(Bohr)) at different levels of PEEP were measured. No differences in respiratory system resistances were found between the ALI and ARDS groups. VD/VT(Bohr) and expired CO2 slope beyond VAE were higher in ALI patients (0.52+/-0.01 and 13.9+/-0.7 mmHg x L(-1), respectively) compared with control patients (0.46+/-0.01 and 7.7+/-0.4 mmHg x L(-1), p<0.01, respectively) and in ARDS patients (0.61+/-0.02 and 24.9+/-1.6 mmHg x L(-1), p<0.01, respectively) compared with ALI patients. VAE/VT differed similarly (0.6+/-0.01 in control group, 0.43+/-0.01 in ALI group and 0.31+/-0.01 in ARDS group, p<0.01). PEEP had no effect on VAE/VT, expired CO2 slope beyond VAE and VD/VT(Bohr) in any group. A significant correlation (p<0.01) was found between VAE/VT and expired CO2 slope beyond VAE and lung injury score at zero PEEP. Indices of volumetric capnography are affected by the severity of the lung injury, but are unmodified by the application of positive end-expiratory pressure.
...
PMID:Volumetric capnography in patients with acute lung injury: effects of positive end-expiratory pressure. 1067 51

We compared different hybrid mode ITPV (h-ITPV) flow rates, and h-ITPV with intratracheal pulmonary ventilation (ITPV) with respect to CO2 clearance and oxygenation. Surfactant deficiency was induced in six adult rabbits with saline lavage. The study consisted of three phases. Phase 0: Stabilization on conventional mechanical ventilation (CMV). Phase I: Bias flow initiated at same pressure and respiratory rate as Phase 0. Flow rates of 25%, 50%, 75% h-ITPV, and ITPV were initiated. Animals were transitioned from CMV to 25% h-ITPV proceeding sequentially to ITPV or vice versa. Phase II: Animals were returned to CMV. Statistical analysis included the two-way analysis of variance (ANOVA) and repeated measures ANOVA with Tuckey's test. No difference in PaCO2 was observed among all h-ITPV flow rates or between h-ITPV and ITPV. After bias flow was introduced (transition from Phase 0 to Phase I), PaCO2 decreased by 37%. PaCO2 increased by 119% during Phase II. Oxygenation improved in all animals, particularly in those transitioned to 25% h-ITPV and proceeding to ITPV. No difference in CO2 clearance between ITPV and h-ITPV was observed. Even at low bias flows, excellent CO2 clearance was achieved. Oxygenation was superior when animals were transitioned from CMV to h-ITPV. Hybrid-ITPV offers some advantages over ITPV and may represent a powerful tool in the management of acute respiratory distress syndrome (ARDS).
...
PMID:Comparison of intratracheal pulmonary ventilation with hybrid intratracheal pulmonary ventilation in a rabbit model of acute respiratory distress syndrome by saline lavage. 1050 32

We evaluated the elimination of CO2 in three Japanese adults with carbonic anhydrase II (CA II) deficiency, as compared with that in 10 healthy volunteers. The patients had no signs of respiratory distress. Heart rate, body temperature, ventilation volume, respiratory rate and (a-ET) PCO2 were found to be higher and PaCO2 tended to be higher in the patients than those in the volunteers, while forced vital capacity (FVC), forced expiratory volume in 1s (FEV1), tidal volume, end-tidal PCO2 (PETCO2), pH and HCO3- in arterial blood were lower in the patients. All three patients had non-anion-gap metabolic acidosis, due to renal losses of bicarbonate, but with virtually no compensatory reduction in PaCO2. However, the high VE and PaO2 suggested that respiratory compensation for this metabolic acidosis was occurring, the elimination of CO2 was possibly facilitated by the presence of other carbonic anhydrase isoenzymes in the pulmonary capillaries. Thus, CA II deficiency causes mild to moderate impairments in CO2 elimination.
...
PMID:Elimination of CO2 in patients with carbonic anhydrase II deficiency, with studies of respiratory function at rest. 1054 85

Congenital cystic adenomatoid malformation (CCAM) is a congenital malformation of the lung that can present on imaging studies as abnormal air, air/fluid-filled cysts, or fluid-filled/solid-appearing cysts. The use of ultrasound in prenatal management has increased the number of cases diagnosed in utero. Early diagnosis is vital in the medical management of CCAM. Outcome varies from hydrops and fetal demise to complete resolution before birth. Many CCAMs diagnosed in utero may decrease in size even if substantial mediastinal shift and lung compression are noted at the time of diagnosis. Once the disorder has been diagnosed, use of serial ultrasound is helpful in providing medical management of the fetus. Two cases of CCAM in the newborn are presented that reflect characteristic clinical features but with distinctly different outcomes, one patient successfully responding to resection and ventilatory support, the other succumbing in the first day of life. The embryology, histology, prenatal and postnatal clinical presentation, and treatment of this malformation are discussed on the basis of a review of the literature. Recent developments in fetal diagnosis and treatment, including fetal surgery, are also presented. We conclude that CCAM should be considered in the differential diagnosis in the presence of respiratory distress and mediastinal shift. It is especially important for respiratory therapists, nurses, and other members of neonatal transport teams to consider CCAM in the differential diagnosis for any patient who presents with respiratory distress and a chest radiograph showing mediastinal shift. The treatment of choice for this lesion is surgical resection by either segmentectomy or lobectomy. Even in cases of relatively asymptomatic patients with CCAM, surgical resection should be considered because of the reported association of carcinoma and unresected CCAM. (IO2)) of 1.0 at a rate of 60-100 breaths per minute, there was slight improvement in oxygen saturation, to 50-70%. The postintubation radiograph showed bilateral haziness, with a mediastinal shift to the right. An umbilical venous catheter was placed and a venous blood gas study revealed a pH of 6.82, partial pressure of carbon dioxide of 100 mm Hg, and partial pressure of oxygen of 36 mm Hg. A needle aspiration of the left chest wall was performed to relieve the mediastinal shift; it produced approximately 40 mL of clear fluid. A repeat chest radiograph showed a possible pneumothorax on the left and continued mediastinal shift. A left-side chest tube was inserted and clear fluid continued to drain, but an additional chest radiograph was unchanged. Needle aspiration was then performed on the left side, and a large amount of air was removed. The S(pO2) increased to 88%, and the heart rate and blood pressure remained stable. The patient was then prepared for transport and placed on a Biomed MPV 10 (Bio-Med Devices, Guilford, Connecticut), intermittent mandatory ventilation rate 120, peak pressure 25 cm H(2)O, positive end-expiratory pressure 5 cm H(2)O (25/5), and F(IO2) 1.0. A venous blood gas study just before transport showed a pH of 7.1 and a P(CO2) of 45 mm Hg. The S(pO2) at that time was between 60% and 70%. To facilitate ventilation during transport, the patient was also given pancuronium (Pavulon) and morphine. On arrival at the neonatal intensive care unit, the patient was placed on a Sensormedics High-Frequency Oscillator (Sensormedics Corporation, Yorba Linda, California) with an initial amplitude of 70, airway pressure 25 cm H(2)O, inspiratory time 33%, Hertz 13, and F(IO2) 1.0. Three additional chest tubes were placed in the left hemithorax, which initially evacuated air, followed by serosanguineous fluid. The S(pO2) briefly increased to above 90%. A repeat chest radiograph again showed persistence of the left-sided collection of air and mediastinal shift. (ABSTRACT TRUNCATED)
...
PMID:Congenital cystic adenomatoid malformation in the newborn: two case studies and review of the literature. 1105 98

This study was performed to elucidate the mechanism of improved oxygenation after surfactant replacement therapy in respiratory distress syndrome (RDS) of the newborn infants. In 26 newborns with RDS, end tidal-CO2 tension (PetCO2), arterial blood gas analysis and pulmonary function tests were measured at baseline, 30 min, 2 hr and 6 hr after surfactant administration. The changes in dead space/tidal volume ratio (VD/VT ratio=(PaCO2-PetCO2)/PaCO2), oxygenation index and arterial-alveolar partial pressure difference for oxygen ((A-a)DO2) were elucidated and correlated with pulmonary mechanics. Oxygenation index and (A-a)DO2 improved, and VD/VT ratio decreased progressively after surfactant administration, becoming significantly different from the baseline at 30 min and thereafter with administration of surfactant. Pulmonary mechanics did not change significantly during the observation period. VD/VT ratio showed close correlation with OI and (A-a)DO2, but not with pulmonary mechanics. These results suggest that decreased physiologic dead space resulting from the recruitment of atelectatic alveoli rather than improvement in pulmonary mechanics is primarily responsible for the improved oxygenation after surfactant therapy in the RDS of newborn.
...
PMID:Changes in dead space/tidal volume ratio and pulmonary mechanics after surfactant replacement therapy in respiratory distress syndrome of the newborn infants. 1128 1

Acute Respiratory Failure (ARF) results in an inability to maintain gas exchange at a rate commensurate with the demands of the body and results in hypoxemia and/or hypercarbia, the mechanisms of which may be different. Hypoxemia commonly occurs due to Ventilation Perfusion (V/Q) mismatching, intrapulmonary shunt, diffusion defect or hypoventilation. Hypercarpnic respiratory failure may also be multifactorial but is usually due to inhibited central respiratory drive or inefficient respiratory muscle pump. Hypercapnia may occur in upper and lower airways obstruction, respiratory muscle fatigue and occasionally due to excess CO2 production (burns and excessive glucose administration). Issues in management centre around assessment of severity, determining the need for intervention, establishing diagnosis and etiology and institution of specific treatment. Diagnosis of respiratory failure may be made clinically and confirmed by blood gas analysis. Calculation of oxygenation indices will delineate extent of hypoxemia. When evaluating a child with respiratory failure, one should be aware that a child with prominent respiratory symptoms may have non-respiratory disease (i.e. metabolic acidosis, DKA) and conversely, advanced respiratory failure may be present in a child with no respiratory distress (central hypoventilation secondary to drugs, infection) careful assessment of history, complete physical examination and evaluation of lab parameters may clarify the diagnosis. Serial assessment of sensorium, respiratory symptoms, ABG and response to treatment will provide valuable clues to determine the need for intervention. Oxygen, like any drug, must be administered in a prescribed dose, only when indicated with the potential risks borne in mind. A variety of oxygen delivery devices are available; which ever device is used, the resulting FiO2 and devisable end points must be clearly determined. Hazards of oxygen therapy range from retinal damage in premature infants, damage to the alveolar capillary membrane with resultant hypoxemia) atelectasis and decreased mucociliary activity.
...
PMID:Acute respiratory failure and oxygen therapy. 1133 23

An MRI method is described for demonstrating improved oxygenation of human tumors and normal tissues during carbogen inhalation (95% O2, 5% CO2). T2*-weighted gradient-echo imaging was performed before, during, and after carbogen breathing in 47 tumor patients and 13 male volunteers. Analysis of artifacts and signal intensity was performed. Thirty-six successful tumor examinations were obtained. Twenty showed significant whole-tumor signal increases (mean 21.0%, range 6.5-82.4%), and one decreased (-26.5 +/- 8.0%). Patterns of signal change were heterogeneous in responding tumors. Five of 13 normal prostate glands (four volunteers and nine patients with nonprostatic tumors) showed significant enhancement (mean 11.4%, range 8.4-14.0%). An increase in brain signal was seen in 11 of 13 assessable patients (mean 8.0 +/- 3.7%, range 5.0-11.7%). T2*-weighted tumor MRI during carbogen breathing is possible in humans. High failure rates occurred due to respiratory distress. Significant enhancement was seen in 56%, suggesting improved tissue oxygenation and blood flow, which could identify these patients as more likely to benefit from carbogen radiosensitization.
...
PMID:BOLD MRI of human tumor oxygenation during carbogen breathing. 1147 74

Observations of the behavioral reactions of laying hens and broilers to different gas stunning atmospheres were made. Sixty Hy-Line W-36 hens and 60 market-weight commercial broilers were placed individually into a plexiglass gas stunning unit and exposed to one of six gas atmospheres: air, concentrations of 30, 45, or 60% CO2 in air, a mixture of 70% argon and 30% CO2, and 100% argon. Video records were made during each test, which lasted until the subject became unconscious or for 2 min in the air treatment. Behavior in the 100% argon atmosphere resembled that in air, until birds became impaired by anoxia. All treatments involving CO2, including 70% argon/30% CO2, caused deep breathing and head shaking. The concentration of CO2 in air in the range tested did not affect the tendency to perform different actions, except that birds in 60% CO2 were more likely to exhibit a convulsive flip at the point of collapse. Chickens in 70% argon/30% CO2 tended to demonstrate less sedation and performed more sudden efforts to regain balance during tests than did chickens in CO2 mixtures in air and were more likely to perform a convulsive flip. Deep breathing and head shaking have been suggested as being indicative of respiratory distress and aversive reaction to CO2. The data in this study are consistent with the possibility that head shaking is an alerting response functioning to promote arousal in the face of reduced sensibility during exposure to CO2-enriched atmospheres. Nonetheless, if the view is correct that deep breathing and head shaking indicate distress, the 70% argon/30% CO2 gas mixture was at least as distressing as even 60% CO2 in air. The relative prevalence of sudden efforts to regain balance in 70% argon/30% CO2 suggest that this gas mixture might cause even more distress than up to 60% CO2 in air.
...
PMID:Reactions of laying hens and broilers to different gases used for stunning poultry. 1155 25


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---