摘要:

Inhibition by prostaglandin E1(PGE1) of superoxide anion (O2) production by isolated intact human neutrophils (PMNs) was investigated utilizing initial-velocity enzyme kinetics. Lag time, linearity, rate, and extent of reaction were simultaneously examined. Dose-response data indicate progressive PGE1-induced suppression of O&OV0276; synthesis by activated PMNs with a Kivalue of 0.50 and 0.98 μmol/L for initial velocity and extent of reaction, respectively. There were no significant dose-related trends for either lag time or linearity for reactions with PGE1concentrations less than 10-6mol/L; however, at concentrations of 10-8mol/L and greater, the length of reaction was progressively shortened. PGE1inhibition of PMN-induced O&OV0276; production does not involve PMN activation/desensitization since PGE1itself cannot stimulate O&OV0276; generation. Moreover, PGE1does not function as a free-radical scavenger. These data indicate the clinical feasibility of utilizing PGE1to titrate PMN-induced synthesis of active oxygen metabolites, in order to attenuate PMN-associated host au-toinjury.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

The likelihood of survival to 28 days of life was determined retrospectively for 106 infants weighing less than 801 g at birth. Multiple logistic regression analysis revealed that birth weight and inspired oxygen fraction made an independent contribution to the prediction of survival at 8 h of age (predictive accuracy 76%). At 16 and 24 h of age, body temperature, pH, and the presence of spontaneous breaths were the independent variables predicting survival (predictive accuracy 79%). Of 37 infants with calculated chances of survival of less than 50% at 16 h, 29 died (predictive accuracy 78%). Seven of the remaining eight infants who survived “against the odds” either died later of chronic lung disease or had severe handicapping complications by 3 months of age. These predictions are first approximations and are not intended for use in making decisions about patient management.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

This retrospective review of 83 infants undergoing CPR in the neonatal ICU of a teaching hospital found that 12 (14%) patients were discharged from the hospital and seven (8%) were alive at least 1 yr after discharge. Of these seven, five appeared neurologically intact. From another perspective, 41% (12/29) of the patients who survived at least 24 h after CPR were discharged alive.Factors significantly (p< .05) associated with poor outcome included sepsis, oliguria 24 h before and/or after arrest, prematurity, and intraventricular hemorrhage. Variables significantly (p< .05) related to good outcome were the need for intubation during resuscitation and the diagnosis of major congenital anomalies. Intraventricular hemorrhage was the single most powerful variable in the regression analysis. Outcome statistics from this study were strikingly similar to currently available adult data.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

The high cost of treatment in an ICU is clearly recognized; the ultimate benefit of that care in prolonging meaningful life is not as well quantified. We evaluated 337 mixed medical-surgical ICU patients for severity of illness and intensity of therapy and assessed their survival and quality of life 16 to 20 months after discharge. Mortality was 36.9% for emergency surgical and medical patients and 13.9% for elective surgical patients. A total of 140 patients responded to follow-up; 62.2% of patients not retired or homemakers were working full-time. Quality of life was good using both subjective and objective standards. There were few significant differences between elective surgical and other patients. Survival and life quality were related inversely to severity of illness and cost of treatment. Acute health on ICU admission predicted survival well; chronic health and age were better predictors of life quality

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

This study describes the long-term functional outcomes of a medical and coronary care ICU population. Baseline and 1-yr follow-up data were collected prospectively from all 2213 patients admitted during a 2-yr period. Patients were stratified into three groups based on their preadmission functional status: active (n = 917), sedentary (n = 1017), or severely limited (n = 279).Those with severe functional limitation before admission were twice as likely to undergo major interventions (p < .005). This group also had a significantly (p < .001) higher mortality and incurred significantly (p < .01) higher hospital charges than the other two groups, even though hospital lengths of stay were similar. Finally, cumulative mortality was significantly (p < .001) greater for the severely limited patients: 33% expired in the ICU, 42% died while still in the hospital, and 63% died after discharge.Most survivors regained their preadmission functional status, with 60% of the previously employed returning to work. However, even for hospital survivors, mortality was high and was related to prior functional status: active 7%, sedentary 20%, severely impaired 37%.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

To further characterize the adrenocortical response to acute illness, we measured basal and adrenocorticotropic hormone (ACTH)-stimulated 11-deoxycortisol, androstenedione, and dehydroepiandrosterone sulfate (DHEAS). Acutely ill patients had higher ACTH-stimulated 11-deoxycortisol and androstenedione, and decreased basal and ACTH-stimulated androstenedione/ Cortisol and DHEAS/cortisol ratios. Our data suggest that a shift away from androgen synthesis toward the glucocorticoid pathway occurs in acute illness.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Positive end-expiratory pressure (PEEP) is a standard treatment for patients with refractory hypoxemia due to an acute restrictive pathology. The therapeutic range of PEEP can be quite narrow. PEEP therapy has been optimized using invasive variables such as oxygen transport and pulmonary shunt, and noninvasive variables such as compliance; however, the measurements are complex. We constructed a computerized PEEP-optimization system consisting of a Siemens 900C ventilator, Siemens prototype sulfur hexafluoride analyzer, Siemens 940 lung mechanics analyzer, and a DEC 11/ 23 microcomputer. The user may choose from three different noninvasive PEEP titration algorithms: maximizing static total respiratory system compliance (CTR), maximizing functional residual capacity(FRC)-based compliance (CFRC), and normalizing FRC. The device was tested in six dogs with pulmonary injury induced by oleic acid. The system was constrained to 3-cm H2O PEEP steps at 20-min intervals. The algorithm normalizing FRC reached optimal PEEP levels in 40 min, with a mean difference from the desired FRC of 15 ± 48 (SEM) ml. This corresponds to a mean percent error of 1.0% ± 2.63%. The CFRCand CTRalgorithms reached optimal PEEP levels in 60 and 40 min, respectively, and maintained a maximal compliance for 85% of the time. This system provides fully automated noninvasive PEEP titration and is flexible enough to incorporate easily any other PEEP titration algorithms. It should improve patient care by guaranteeing that PEEP therapy is truly optimized throughout the patient's recovery.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

A randomized crossover protocol was used to compare conventional mechanical ventilation (CMV) and high-frequency ventilation (HFV) in mongrel dogs experiencing right ventricular dysfunction after right ventriculotomy. When inspired oxygen, pH, Pco2, core temperature, and preload were held constant, cardiac output increased significantly (p < .05) from 1.16 ± 0.24 to 1.38 ± 0.25 L/min and pulmonary vascular resistance decreased significantly (p < .05) from 734 ± 257 to 554 ± 169 dyne sec/cm5 during HFV relative to CMV. We also noted a significant (p < .05) increase in mean arterial pressure from 116 ± 27 to 124 ± 23 mm Hg and a significant (p < .05) increase in left ventricular stroke work from 10.2 ± 3.5 to 12.3 ± 2.6 gm during HFV. During the inspiratory phase of CMV there were increases in CVP, pulmonary artery pressure, and systemic arterial pressure, and decreases in pulmonary artery flow which did not occur during HFV. HFV may be preferable to CMV in the presence of right ventricular dysfunction.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

The effects of endotoxin on pulmonary hemodynamics were studied in seven intact dogs. The distribution of pulmonary vascular resistance was estimated by the effective pulmonary capillary pressure, which was derived from the pressure transient recorded while the pulmonary artery catheter was rapidly wedged. After the injection of endotoxin, cardiac output and aortic pressure consistently fell. Pulmonary artery occlusion (wedge) pressure also decreased, but not significantly. Although pulmonary artery pressure did not necessarily rise, total pulmonary vascular resistance increased in every dog. The absolute increase in pulmonary artery resistance was greater (142 mm Hg/L min/kg) than in venous resistance (111 mm Hg/L min/kg); however, the relative increase in venous resistance was higher (410% for venous resistance vs. 220% for pulmonary artery resistance). As a result of venoconstriction, there was a consistent increase in effective pulmonary capillary pressure (from 2.5 to 6.3 mm Hg). Our data indicate that the pulmonary vascular response to endotoxin injection is characterized by constriction of both pulmonary arteries and pulmonary veins. The capillary wedge pressure did not reflect the pulmonary microvascular pressure, since it varied in the opposite direction to the effective capillary pressure.

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

Measuring gas exchange in critically ill patients can provide valuable information on their nutritional status and energy expenditure. Several semiautomated machines are available for measuring oxygen consumption (Vo2) and carbon dioxide production (Vco2). This study evaluated, under controlled laboratory conditions, a Gould 9000 IV prototype designed for use with mechanically ventilated patients. Various Vo2and Vco2values were simulated at different combinations of frequency, tidal volume, minute ventilation, and inspired oxygen fraction (Fio2)Variations in frequency, tidal volume, and minute ventilation had no significant effect on the measured V02 and Vco2, but Fio2had a dramatic effect on the accuracy of Vo2. Errors in measured Vo2were 2.6%, 3.5%, 5.9%, and 16.9% at Fio2values of 0.22, 0.40, 0.60, and 0.80, respectively. Addition of a dead space to the spirometer dump port (to prevent room-air contamination) corrected a larger error initially found. The accuracy of Vco2was ± 2.6%

ISSN:0090-3493    

出版商:OVID    

年代:1986

数据来源: OVID