ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

ObjectiveTo determine whether low “stretch” mechanical ventilation protects animals from clinical sepsis after direct acute lung injury withPseudomonas aeruginosaas compared with high “stretch” ventilation.DesignProspective study.SettingExperimental animal laboratory.SubjectsTwenty-seven anesthetized and paralyzed rabbits.InterventionsP. aeruginosa(109colony forming units) was instilled into the right lungs of rabbits that were then ventilated at a tidal volume of either 15 mL/kg (n = 11) or 6 mL/kg (n = 7) for 8 hrs. Control animals were ventilated at a tidal volume of either 15 mL/kg (n = 4) or 6 mL/kg (n = 5) for 8 hrs, but an instillate without bacteria was used. A positive end-expiratory pressure of 3–5 cm H2O was used for all experiments. Radiolabeled albumin was used as a marker of alveolar epithelial permeability.Measurements and Main ResultsHemodynamics, arterial blood gas determination, alveolar permeability, wet-to-dry ratios on lungs, and time course of bacteremia were determined. When final values were compared with the values at the beginning of the experiment, there were significant decreases in mean arterial pressure (from 104 ± 15 to 57 ± 20 mm Hg), pH (from 7.46 ± 0.04 to 7.24 ± 15), Pao2(from 528 ± 35 to 129 ± 104 torr [70.4 ± 4.7 to 17.2 ± 13.9 kPa]), and temperature (from 38.2 ± 1 to 36.2 ± 1.2°C) in the high tidal volume group, whereas no significant differences were found in the low tidal volume group. Decreased alveolar permeability was shown in the low tidal volume group, as was decreased extravascular lung water in the uninstilled lung in the low tidal volume group (12.7 ± 2.5 vs. 4.3 ± 0.45 g H2O/g dry lung). No noteworthy difference was noted in the time course of bacteremia, although there was a trend toward earlier bacteremia in the high tidal volume group.ConclusionsIn our animal model ofP. aeruginosa-induced acute lung injury, low tidal volume ventilation was correlated with improved oxygenation, hemodynamic status, and acid-base status as well as decreased alveolar permeability and contralateral extravascular lung water.

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

ObjectiveAdenosine decreases the cerebral metabolic rate for oxygen and increases cerebral blood flow, and it may play an important role in cerebrometabolic and cerebrovascular responses to hypoperfusion after traumatic brain injury. Jugular venous oxygen saturation is monitored after traumatic brain injury to assess brain oxygen extraction, and desaturations may reflect secondary brain insults. We hypothesized that brain interstitial adenosine and related purine metabolites would be increased during jugular venous oxygen saturation desaturations (<50%) and determined associations between the purines, lactate, and glucose to assess the role of adenosine during secondary insults in humans.DesignStudy of critically ill adults with severe traumatic brain injury.SettingAdult neurointensive care unit.PatientsWe prospectively defined periods of normal saturation and desaturation in six patients after severe traumatic brain injury.InterventionsDuring these periods, cerebral microdialysis samples of brain interstitial fluid were collected, and adenosine and purine metabolites were measured by high-pressure liquid chromatography.Measurements and Main ResultsAdenosine increased 3.1-fold and xanthine increased 2.5-fold during desaturation periods (bothp< .05 vs. normal saturation period, signed rank). Adenosine, xanthine, hypoxanthine, and cyclic-adenosine monophosphate correlated with lactate over both study periods (r2= .32, .14, .31, .07, and .26, respectively, allp< .05, Pearson product moment correlation).ConclusionThe marked increases in interstitial brain adenosine that occur during jugular venous oxygen desaturations suggest that adenosine may play an important role during periods of secondary insults after traumatic brain injury. The correlation of these metabolites with lactate further suggests that adenosine is increased during periods of enhanced glycolytic metabolism.

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

ObjectiveNosocomial infection is an important contributor to morbidity and mortality in pediatric solid organ transplantation. The relative effect of protective gown and glove isolation was compared with strict handwashing in pediatric intensive care unit (PICU) patients with solid organ transplantation.Design/SettingA prospective, randomized design was used; children in a 23-bed PICU with solid organ transplantation were enrolled into a gown and glove protective isolation protocol or a strict handwashing protocol.PatientsAll children admitted to the PICU immediately after solid organ transplantation, excluding renal transplantation, and at subsequent readmissions to the PICU were eligible for the study. Children with current infection or known exposure to varicella were excluded from the study initially or at readmission.InterventionsBy using a block randomization design based on organ transplanted, age, and initial admission vs. readmission, each patient was randomized to either strict handwashing or protective gown and glove isolation intervention groups.MeasurementsWe analyzed demographics, infection outcomes (defined according to Centers for Disease Control criteria), and monitoring of patient contacts in compliance with protocols.ResultsThe infection rate in the overall PICU population did not change significantly from the year before the study compared with during the study (2.1 per 100 vs. 1.95 per 100 patient days;p= .4) The infection rate in the gown and glove group (2.3 per 100 patient days) was reduced significantly compared with the prestudy infection rate in the transplant population (4.9 per 100 patient days;p= .0008). Strict handwashing also significantly reduced the infection rate in the transplant population (3.0 per 100 patient days;p= .008). Compliance with gowning and gloving was 82% and compliance with handwashing was 76% (compared with 22% before study [p< .0001] and 52% after the study [p< .0001]). Despite an increased mean length of stay in the PICU in the gown and glove group (p= .014), there was a trend toward reduction in the incidence of infection (Fisher’s exact test,p= .07; odds ratio, .76) in the gown and glove group.ConclusionsIncreased compliance with handwashing was associated with a reduction in nosocomial infections, and gown and glove isolation appeared to have an additional protective effect. Some nosocomial infections may be preventable in the pediatric solid organ transplantation population.

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

ObjectiveTo improve the accuracy of ventilatory measurements in ventilated newborns by means of a numerical correction when a deadspace free differential measuring method using two pneumotachographs (PNTs) is applied and to investigate the clinical usefulness of this correction procedure.DesignIn vitrostudy and prospective animal study.SettingResearch laboratory of the Clinic of Neonatology and the Animal Research Laboratory, Charité Hospital Berlin.SubjectsTen newborn piglets, weighing 610–1340 g (median, 930 g), age <12 hrs.InterventionsThe accuracy of both the deadspace free method and the endotracheal flow measurements (conventional method) was investigated using mechanical lung models. A correction procedure for the deadspace free method was developed considering signal delay time and tube compliance between both PNTs. This method was applied to the piglets measured during partial liquid ventilation (PLV). Measurements were done before and after lung lavage and during 30 and 120 mins of PLV (30 mL/kg body weight perfluorocarbon).Measurements and Main ResultsIn vitromeasurements showed volume differences between both methods of 8%, 12%, 16%, and 17%, respectively, depending on the distance between the PNTs of 10, 60, 120, and 180 cm. After applying the correction algorithm, the differences decreased to 3%, 0%, −2%, and −8%, respectively. The piglets were measured with 120-cm tube length between the PNTs. The correction algorithm reduced the measured tidal volume before lavage by 7%, after lavage by 14%, 30-min PLV by 12%, and 120-min PLV by 10%, corresponding to the changes in respiratory compliance of 1.2, 0.6, 1.0, and 1.1 mL/cm H2O.ConclusionsThe deadspace free method can be advantageously used for continuous measurements in newborns despite much higher technical expense. The correcting procedure improved the accuracy of the volume measurement remarkably, especially for lower respiratory compliance.

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

ObjectivesTo determine the accuracy of the Paratrend 7 continuous intra-arterial blood gas monitor (CI-ABGM) in radial and femoral artery catheters placed in children compared with simultaneous measurements of pH, Paco2, and Pao2performed by intermittent blood gas analysis. To determine sensor longevity in pediatric patients at different arterial sites. To determine the utility of CI-ABGM for tracking unanticipated events related to blood gas deterioration.SettingA pediatric intensive care unit of a university hospital.DesignA prospective clinical investigation.PatientsFifty critically ill pediatric patients, ranging in age from 1 wk to 18 yrs of age, who required either radial or femoral artery catheters for intermittent arterial blood gas monitoring.InterventionsNone.Measurements and Main ResultsA Paratrend 7 intra-arterial sensor was placed through either an 18- or 20-gauge catheter previously inserted into the radial or femoral artery. At clinically predetermined intervals ranging from every 1 to 8 hrs, the CI-ABGM measurements of pH, Pco2, and Po2were compared with the values determined by standard intermittent blood gas analysis. The Paratrend 7 system values were individually adjusted to match ABG results when the Paratrend 7 pH differed by greater than ±0.05 units, Pco2was greater than ±5 torr (0.7 kPa), and Po2was greater than ±15% of the ABG value. Significant aberrations in gas exchange defined as unanticipated events were categorized as isolated metabolic acidosis (pH <7.20), hypercapnia (Pco2, >70 torr; 9.3 kPa), and hypoxemia (Po2, <50 torr; 6.7 kPa). All unanticipated events were earmarked from consecutive monitoring epochs ranging from 4 to 24 hrs duration from the time of Paratrend 7 sensor insertion to the time of sensor removal. Fifteen sensors were placed into the radial artery, 34 sensors were placed into the femoral artery, and one sensor was initially placed in the radial and moved to a femoral artery location. Mean radial artery insertion duration was 35 hrs. Mean femoral artery duration was 137.2 hrs. A total of 1445 pairs of ABG results were available for comparison. After removal of individual values, which did not meet inclusion criteria, 1411 pH data pairs, 1408 Pco2data pairs, and 1326 Po2data pairs were analyzed. The bias and precision for the pH data were 0.00 and 0.04 units, respectively; for the Pco2data were −0.4 and 4.8 torr (−0.05 and 0.64 kPa), respectively; and for the Po2data 1.0 and 25 torr (0.1 and 3.3 kPa), respectively. Detection of unanticipated events was evenly spread across the three categories and was most commonly related to iatrogenic causes or cardiac failure. Persistent waveform dampening necessitating sensor removal was more frequently encountered in radial placement compared to femoral placement.ConclusionsThe Paratrend 7 CI-ABGM is accurate within the extremes of physiologic gas exchange typically encountered in the pediatric intensive care setting. The device is capable of tracking extreme fluctuations in gas exchange with a response rate suitable for making real-time therapeutic decisions. The sensor can be recommended for insertion into a femoral artery cannula. There is a high incidence of blood pressure waveform dampening encountered in radial artery use.

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

ObjectiveTo review the history and current applications of artificial intelligence in the intensive care unit.Data SourcesThe MEDLINE database, bibliographies of selected articles, and current texts on the subject.Study SelectionThe studies that were selected for review used artificial intelligence tools for a variety of intensive care applications, including direct patient care and retrospective database analysis.Data ExtractionAll literature relevant to the topic was reviewed.Data SynthesisAlthough some of the earliest artificial intelligence (AI) applications were medically oriented, AI has not been widely accepted in medicine. Despite this, patient demographic, clinical, and billing data are increasingly available in an electronic format and therefore susceptible to analysis by intelligent software. Individual AI tools are specifically suited to different tasks, such as waveform analysis or device control.ConclusionsThe intensive care environment is particularly suited to the implementation of AI tools because of the wealth of available data and the inherent opportunities for increased efficiency in inpatient care. A variety of new AI tools have become available in recent years that can function as intelligent assistants to clinicians, constantly monitoring electronic data streams for important trends, or adjusting the settings of bedside devices. The integration of these tools into the intensive care unit can be expected to reduce costs and improve patient outcomes.

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:0090-3493    

出版商:OVID    

年代:2001

数据来源: OVID