摘要:

Objective:To study cerebral glucose and lactate metabolism in head-injured patients using microdialysis.Design:Prospective, nonrandomized, clinical study.Setting:Neurosurgical intensive care unit in a university-affiliated county hospital.Patients:One hundred twenty-six head-injured patients.Interventions:Cerebral cortical neurochemical monitoring using microdialysis coupled with systemic hemodynamic and oxygenation monitoring, measurement of cerebral perfusion pressure and intracranial pressure, and measurement of global cerebral oxygenation using jugular venous oxygen saturation in all 126 patients. In selected cases, cerebral blood flow was also measured using cortical thermodilution probes in 33 patients, and regional cerebral oxygenation was measured using PO2probes in 65 patients.Measurements and Main Results:Elevated extracellular lactate, reduced glucose, and an elevated lactate/glucose ratio were observed with cerebral hypoxia and ischemia. Elevated lactate and an increased lactate/glucose ratio strongly correlated with death. Other more subtle alterations of lactate and glucose were seen early after injury that may reflect compensatory alterations in cerebral metabolism.Conclusions:Clinical neurochemical monitoring of glucose and lactate levels in the extracellular space of the cerebral cortex is technically feasible and provides insight into the bioenergetic status of the brain. Increased lactate and decreased glucose, indicating accelerated glycolysis, commonly occurred with cerebral ischemia or hypoxia, and increased anaerobic glycolysis in this setting is associated with a poor outcome.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Objectives:a) To describe the postoperative course and outcome of cardiac surgery in children with recent respiratory syncytial virus (RSV) infection; and b) to evaluate whether timing of surgery has any impact on the outcome.Design:Retrospective case series.Setting:Intensive care unit and medical and surgical wards of a teaching pediatric hospital.Patients:Twenty-five children (aged 25 days to 3.5 yrs; median, 4 months) with congenital heart disease who had cardiac surgery within 6 months after RSV infection.Interventions:None.Measurements and Main Results:We reviewed the clinical course and outcome of all patients. The cardiac diagnoses included ventricular septal defect (n = 11), tetralogy of Fallot (n = 3), atrioventricular canal (n = 3), and others (n = 8). Thirteen patients had surgery during the same admission as RSV infection (group I), and 12 patients had surgery electively after being discharged to home after RSV infection (group II). Two patients in group I died; both of these patients had undergone total repair of tetralogy of Fallot within 2 wks after admission for RSV infection. Postoperative complications in group I patients included pulmonary hypertension (n = 5), adult respiratory distress syndrome (n = 1), tracheal stenosis (n = 1), left ventricular dysfunction (n = 1), pericardial effusion (n = 1), secondary bacterial or fungal infection (n = 7), and deep venous thrombosis (n = 1). Of all group I patients, the ones who were operated on early appeared to be at higher risk for complications, especially for postoperative pulmonary hypertension. No patient in group II died, and only two patients had minor complications (one had reactive airway disease, and the other had a transient superior vena cava syndrome after a bidirectional Glenn operation).Conclusions:Cardiac surgery performed during the symptomatic period of RSV infection is associated with a high risk of postoperative complications, especially postoperative pulmonary hypertension. These complications appeared to be more frequent and of greater severity in patients who had earlier surgery compared with those who had later surgery. More studies are needed regarding the proper timing of cardiac surgery in patients with congenital heart disease and RSV infection.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Objective:To implement and retrospectively evaluate a therapeutic algorithm for the treatment of refractory status epilepticus with midazolam coma.Methods:Eight consecutive patients with refractory status epilepticus were mechanically ventilated. Their arterial and central venous blood pressures were continuously monitored by indwelling vascular catheters. These patients were also continuously monitored by a 16-channel video electroencephalogram (EEG). A midazolam bolus of 0.15 mg/kg was administered, and a continuous infusion of 1-2 μg/kg/min was started. If seizures continued, the infusion was increased every 15 mins by 1-2 μg/kg/min. If seizures stopped and/or burst suppression was achieved, the patients continued to receive that dose for 48 hrs and were then weaned by decrements of 1-2 μg/kg/min every 15 mins.Results:The patients' ages ranged from 17 days to 16 yrs, and they had various underlying diseases. In five of the eight patients, cessation of seizures occurred before achieving burst suppression on EEG, in two patients, cessation occurred during burst suppression, and in one patient, no response before or during burst suppression was encountered. The maximal midazolam doses required to achieve cessation of seizures and/or burst suppression, whichever came first, ranged from 4-24 μg/kg/min, with a mean of 14 ± 6 μg/kg/min. The patients maintained stable cardiovascular function while receiving the maximal dose of midazolam and did not require inotropic support.Conclusion:Midazolam infusion, as per our described algorithm, is effective in terminating refractory status epilepticus. This treatment is not associated with cardiovascular instability, even at doses resulting in burst suppression. In the majority of cases, cessation of seizures occur before burst suppression is achieved on EEG.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Objective:To evaluate the reliability and precision of measurement in a new thoracic electrical bioimpedance (TEB) monitor.Design:Prospective clinical trial using healthy volunteers.Setting:Military tertiary care teaching hospital.Subjects:Seventy-five healthy adult volunteers taking no medications.Interventions:Induction of severe preload reduction using a standardized lower-body negative pressure protocol. Measurement of hemodynamic variables using a TEB monitor before, during, and immediately after application of negative pressure.Measurements and Results:Seventy-five subjects were enrolled and completed the study. Pulse, blood pressure, stroke index, cardiac index, systolic time ratios (STR), and index of contractility were obtained on all subjects undergoing monitoring with the lower body negative pressure (LBNP) device. Hemodynamic measurements were recorded at 15-sec intervals during incremental application of 0, −10, −20, −40, and −60 mm Hg pressure for 10 mins at each pressure. Maximal tolerated LBNP produced reductions in cardiac, stroke, and contractility indices of 50%, 65%, and 45%, respectively. Pulse and STRs increased 44% and 113%, respectively. The precision of measurement (mean ± 2 SD) for TEB-derived cardiac and stroke index was 16% and 10%, respectively. Repeatability of measurement was assessed by measuring hemodynamic changes after the abrupt cessation of maximal LBNP. There were significant increases in stroke index (p< .001) and decreases in STRs (p< .001) and pulse (p< .001) 3 mins after LBNP. There was no significant difference between initial and post-LBNP cardiac index (p> .05). Regression equations were applied to scattergram plots of stroke index vs. STRs and index of contractility vs. body mass. The use of these plots allowed elimination of values that appeared to be spurious (stroke index vs. STRs) and also raised the question whether the Sramek-Bernstein equation (stroke volume = left ventricular ejection time × volume of electrically participating tissue × dZ/dt/Zo) fully explained all the factors affecting the TEB waveform.Conclusions:This new monitor appears to overcome many of the signal processing problems encountered with previous devices. The results clearly demonstrate that accurate and reliable measurement of bioimpedance waveforms is possible and suggest that the monitor is capable of generating precise hemodynamic data across a wide spectrum of hemodynamic alterations. However, the evidence also indicates that new algorithms may be needed to more fully explain the multiple factors affecting this waveform.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Objective:To investigate the association of collaboration between intensive care unit (ICU) physicians and nurses and patient outcome.Design:Prospective, descriptive, correlational study using self-report instruments.Settings:A community teaching hospital medical ICU, a university teaching hospital surgical ICU, and a community non-teaching hospital mixed ICU, all in upstate New York.Subjects:Ninety-seven attending physicians, 63 resident physicians, and 162 staff nurses.Procedure:When patients were ready for transfer from the ICU to an area of less intensive care, questionnaires were used to assess care providers' reports of collaboration in making the transfer decision. After controlling for severity of illness, the association between interprofessional collaboration and patient outcome was assessed. Unit-level organizational collaboration and patient outcomes were ranked.Measures:Healthcare providers' reported levels of collaboration, patient severity of illness and individual risk, patient outcomes of death or readmission to the ICU, unit-level collaboration, and unit patient risk of negative outcome.Main Results:Medical ICU nurses' reports of collaboration were associated positively with patient outcomes. No other associations between individual reports of collaboration and patient outcome were found. There was a perfect rank order correlation between unit-level organizational collaboration and patient outcomes across the three units.Conclusions:The study offered some support for the importance of physician-nurse collaboration in ICU care delivery, a variable susceptible to intervention and further study.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Objectives:To examine interobserver reliability of the Acute Physiologic and Chronic Health Evaluation (APACHE) II score and identify major causes of variability in data collection.Design:Descriptive, comparative analysis.Setting:Nine intensive care units in two teaching and six community hospitalsSubjects:A random sample of 342 patient records selected from a network database.Intervention:None.Measurements and Main Results:Data were reabstracted and compared with the original records. Individual physiologic points derived from the APACHE II scoring system (instead of the actual physiologic values) were compared using the kappa statistic. Paired measurements of the continuous variables were compared using the interclass correlation coefficient and Bland-Altman plots. Excellent agreement was found in most demographic, admission, and discharge data. The system failure requiring intensive care unit admission was consistently identified by both data collectors in 88% of cases, but only 66% agreed on the exact admitting diagnosis. For APACHE II score components, the kappa statistic ranged from 0.315 for the Glasgow Coma Scale point to 0.976 for the age point. Significant disagreement regarding the probability of death derived from the APACHE II model was evident in some patient records. Overall agreement among groups of patients regarding the APACHE II score was good, however, with no significant difference in the mean score (20.2 vs. 20.1;p= .758). The predicted mortality from the reabstracted data was 30%, similar to the 27% predicted mortality from the original data (p= .380).Conclusion:Reliability of data collection varied widely in different components of the APACHE II probability-of-death model. Significant discrepancies in some components suggested a lack of explicit definitions and timing for consistent data collection between institutions or between data collectors. Nonetheless, variability resulting from data collection appears to be randomly distributed, so that comparisons of group means are valid.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Objective:To identify the goals and methods for medical education about end-of-life care in the intensive care unit (ICU).Data Sources and Study Selection:A status report on palliative care, a summary report of recent research on palliative care education, articles in the medical literature on end-of-life care and critical care, and expert opinion were considered.Data Extraction:A working group, including specialists in critical care, palliative care, medical ethics, consumer advocacy, and communications, was convened at the "Medical Education for Care Near the End of Life National Consensus Conference." A modified nominal group process was used to develop a consensus.Data Synthesis:In the ICU, life and death decisions are often made in a crisis mode or in the face of uncertainty, and may necessitate the withholding and withdrawal of life-supporting technologies. Because critical illness often diminishes the capacity of patients to make decisions, clinicians must often make decisions in conjunction with surrogates, rather than with patients. Discontinuity of care can threaten trusting relationships, and cultural diversity can have a particularly powerful impact on choices for care. In the face of these realities, it is possible and appropriate to give compassionate palliative care to dying patients and their families in the ICU.Conclusions:Teaching care of the dying in the ICU should emphasize the following: a) the goals of care should guide the use of technology; b) understanding of prognostication and treatment withholding and withdrawal is essential; c) effective communication and trusting relationships are crucial to good care; d) cultural differences should be acknowledged and respected; and e) the delivery of excellent palliative care is appropriate and necessary when patients die in the ICU.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

摘要:

Objective:To describe an unusual case of acute eosinophilic pneumonia (AEP) associated with hemodynamic instability.Design:Case report, clinical.Settings:Tertiary care intensive care unit (ICU).Patient:A single patient admitted to the ICU.Interventions:Intravenous corticosteroids.Measurements and Main Results:Resolution of distributive shock and respiratory failure.Conclusions:AEP with respiratory failure was first reported in 1989 as a distinct clinical entity. Patients with this variant of eosinophilic lung disease develop acute hypoxemic respiratory failure with a rapid response to treatment with corticosteroids. The characteristic feature of this syndrome is a predominance of eosinophils found in bronchoalveolar lavage fluid and lung biopsy. Despite the increasing number of reported cases, to our knowledge, distributive shock has not been reported as a feature of AEP. We report a unique case of AEP associated with shock and review the pertinent literature.

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID

ISSN:0090-3493    

出版商:OVID    

年代:1999

数据来源: OVID