摘要:

ObjectiveRepeated induction of ventricular fibrillation with ensuing alterations in electroencephalogram and jugular venous oxygen saturation is common practice during insertion of transvenous implantable cardioverters/defibrillators. We investigated whether these functional changes are also associated with cerebral injury.DesignProspective study.SettingUniversity hospital.PatientsWe studied 45 patients undergoing implantable cardioverter/defibrillator insertion. Eleven patients with cardiac pacemaker implantation, which was performed in the same manner yet without the necessity to induce ventricular fibrillation, served as controls.Measurements and Main ResultsSerum neuron-specific enolase and S100 were determined before, immediately postoperatively, and 2 hrs postoperatively. In a randomly composed subgroup, neuron-specific enolase was also determined 6 and 24 hrs after surgery. Implantable cardioverter/defibrillator patients only showed an increase of both markers postoperatively. Median neuron-specific enolase values climbed from a preoperative 9.9 to 12.3 and 14.4 &mgr;g/L at 2 and 24 hrs after surgery, respectively. This increase was associated with the number of shocks and the cumulative time in circulatory arrest. The highest median S100 level (0.075 &mgr;g/L) was reached 2 hrs after the procedure. Neuron-specific enolase and S100 were extremely elevated (13.7 and 0.970 &mgr;g/L, respectively) in one patient after an extended episode of ventricular fibrillation. Plasma hemoglobin levels were in the normal range in implantable cardioverter/defibrillator patients throughout the observation period.ConclusionsApparently, even brief successive periods of global cerebral ischemia cause neuronal damage without obvious severe neurologic deficits. However, they may be related to subtle postoperative neurologic or cognitive dysfunctions that a number of implantable cardioverter/defibrillator patients exhibit after implantation.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo determine whether selective digestive decontamination (SDD) had some negative impact on the bacterial resistance observed in strains isolated from samples from patients receiving nonabsorbable antibiotics and cefazolin.DesignCase-control study.SettingIntensive care unit of a university tertiary-care hospital.PatientsOver a 6-yr period, 360 multiple trauma patients (case patients) submitted to SDD were compared with 360 patients not receiving SDD (controls).InterventionsSDD consisted of polymyxin E, gentamicin, and amphotericin B and was applied on the buccal mucosa and provided in the nares and the stomach. For the first 3 days, systemic cefazolin (1 g three times a day) was provided. Resistance analysis was performed in case patients and controls on samples collected at predetermined intervals.Measurements and Main ResultsSDD was used in a small subset of patients admitted to the intensive care unit (360 of 5987 over the 6-yr study period). A relative overgrowth of gram-positive cocci was observed. Methicillin resistance ofStaphylococcus epidermidiswas increased (SDD 76%, controls 63%,p< .05) but not that ofStaphylococcus aureus(SDD 20%, controls 18%). Resistance of Enterobacteriaceae,Pseudomonas aeruginosa, andAcinetobacterto &bgr;-lactamines and aminoglycosides was the same in SDD patients and controls.ConclusionsWhen used in a small subset of patients who have been shown to derive benefit from it (patients who have experienced multiple trauma), SDD has a moderate impact on microbial ecology. However, surveillance cultures are indispensable because the absence of resistance to SDD antibiotics determines the long-term safety of the SDD prophylaxis.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveSepsis remains a serious clinical problem, and multiple attempts at blocking inflammation have failed to decrease mortality rate. Interleukin-18 has been demonstrated to be an important component of the innate immune response to bacterial infections.DesignPrevious work demonstrated that elevated plasma concentrations of interleukin-6 obtained in the first 6 hrs of sepsis predict a worse outcome. Mice were subjected to cecal ligation and puncture and, on the basis of the plasma concentration of interleukin-6, were randomized to receive either interleukin-18 binding protein or vehicle approximately 8 hrs after the onset of sepsis.SettingUniversity research laboratory.SubjectsAdult, female BALB/c mice.InterventionsWe sought to determine the role of interleukin-18 in sepsis by blocking its biological activity with the interleukin-18 binding protein in the murine model of sepsis induced by cecal ligation and puncture.Measurements and Main ResultsIn this study, elevated plasma concentrations of interleukin-6 were associated with a worse outcome. Treatment with interleukin-18 binding protein decreased inflammation as determined by lower concentrations of plasma interleukin-6 obtained 48 hrs after the onset of sepsis. In mice with increased risk of dying, interleukin-18 binding protein slightly decreased mortality rate. However, in those mice with a predicted low mortality rate, interleukin-18 binding protein significantly increased mortality rate.ConclusionsIn this study, mice at low risk of death due to sepsis had decreased survival when treated with interleukin-18 binding protein. These results have potential implications for the use of interleukin-18 binding protein for treatment of chronic inflammatory conditions since it may place the host at increased risk of infectious complications.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo determine the steady-state plasma and epithelial lining fluid concentrations of cefepime administered in continuous infusion in critically ill patients with severe bacterial pneumonia.DesignProspective, open-label study.SettingAn intensive care unit and research ward in a university hospital.PatientsTwenty adult patients with severe nosocomial bacterial pneumonia on mechanical ventilation were enrolled.InterventionsAll subjects received a 30-min intravenous infusion of cefepime 2 g followed by a continuous infusion of 4 g over 24 hrs. The concentrations of cefepime in plasma and epithelial lining fluid were determined at steady state after 48 hrs of therapy with high performance liquid chromatography.Measurements and Main ResultsThe mean ± sd steady-state plasma and epithelial lining fluid concentrations of cefepime 4 g in continuous infusion were 13.5 ± 3.3 &mgr;g/mL and 14.1 ± 2.8 &mgr;g/mL, respectively, with a mean percentage penetration of cefepime into epithelial lining fluid of about 100%.ConclusionsThe administration of 4 g of cefepime in continuous infusion in critically ill patients with severe nosocomial pneumonia appears to optimize the pharmacodynamic profile of this &bgr;-lactam by constantly providing concentrations in excess of minimal inhibitory concentration of most of susceptible organisms over the course of therapy in both serum and epithelial lining fluid.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo develop, deploy, and evaluate an intervention designed to identify and mitigate conflict in decision making in the intensive care unit.DesignNonrandomized, controlled trial.SettingSeven intensive care units at four Boston teaching hospitals.PatientsA total of 1,752 critically ill patients, including 873 study cases analyzed here.InterventionSocial workers interviewed families of patients deemed at high risk for decisional conflict and provided feedback to the clinical team, who then implemented measures to address the problems identified.Measurements and Main ResultsPatient or surrogate satisfaction with intensive care unit care and the probability of choosing a specific plan for treatment in the intensive care unit was studied. Inclusion criteria identified 873 patients at risk for decisional conflict. Thirty-nine percent of the patients in the intervention phase of the study (172 patients) received the intervention. In multivariate analyses, receiving the intervention significantly increased the likelihood of deciding to forgo resuscitation (odds ratio [OR] = 1.81,p= .017), the likelihood of choosing a treatment plan for comfort-care only (OR = 1.94,p= .018), and the likelihood of choosing an aggressive-care treatment plan (OR = 2.30,p= .002). Receiving the intervention did not significantly affect overall satisfaction with the care provided (OR = 0.68,p= .14), satisfaction with the amount of information provided (OR = 0.86,p= .44), or satisfaction with the degree of involvement in decision making (OR = 0.84,p= .54).ConclusionsAlthough there was no impact on patient or surrogate satisfaction with care provided in the intensive care unit, the intervention did facilitate deliberative decision making in cases deemed at high risk for conflict. The lessons learned from the experience with this intervention should be helpful in ongoing efforts to improve care and to achieve outcomes desired by critically ill patients, their families, and critical care clinicians.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectivesTo assess the reproducibility of the static pressure-volume curve of the respiratory system by using a “mini-syringe” technique; to assess the temporal change in upper (UIP) and lower inflection points (LIP) measured from pressure-volume curves of the respiratory system; to assess the inter- and intraobserver variability in detection of the UIP and LIP in patients with acute lung injury (ALI)/acute respiratory distress syndrome (ARDS); and to compare the syringe and multiple occlusion techniques for determining LIP and UIP.DesignProspective observational study.SettingAcademic medical-surgical critical care unit.PatientsConsecutive patients with ALI or ARDS.InterventionsStatic inspiratory pressure-volume curves of the respiratory system were determined twice on day 1 of diagnosis of ALI/ARDS and then once daily for up to 6 days by using the syringe technique. Pressure-volume curves were determined from zero positive end-expiratory pressure. At each time point, three separate measurements of the pressure-volume curve were made to determine reproducibility. A 100-mL graduated syringe was used to inflate patients’ lungs with 50- to 100-mL increments up to an airway pressure of 45 cm H2O or a total volume of 2 L; each volume step was maintained for 2–3 secs until a plateau airway pressure was recorded. On day 1, the static pressure-volume curve also was determined by using the multiple occlusion technique. In a random and blinded sequence, the pressure-volume curves were examined visually by three critical care physicians on three different occasions, to determine the intra- and interobserver variability in visual detection of the LIP and UIP. Observers were given objective instructions to visually identify LIP and UIP.Measurements and Main ResultsEleven patients were enrolled, with a total of 134 pressure-volume curves generated. LIP and UIP could be detected in 90–94% and 61–68% of curves, respectively. When the three successive pressure-volume curves were compared, both the LIP and UIP were within 3 cm H2O in >65% of curves. The index of reliability (intraclass correlation coefficient) in LIP and UIP was 0.92 and 0.89 for interobserver variability and 0.90 and 0.88 for intraobserver variability. Daily variability was as high as 7 cm H2O for LIP and 5 cm H2O for UIP. When pressure-volume curves obtained by using the multiple occlusion and syringe techniques were compared, LIP was within 2 cm H2O, and UIP was within 4 cm H2O with the two techniques.ConclusionsThe static pressure-volume curve of the respiratory system is reasonably reproducible, thus avoiding the need for multiple measurements at a single time. We found excellent interobserver and intraobserver correlation in manual identification of the LIP and UIP. Both LIP and UIP show appreciable daily variability in patients with ALI/ARDS. The multiple occlusion and syringe techniques generate similar values for LIP and UIP.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo evaluate the efficacy of bacterial filters (BF) to decrease pneumonia associated with mechanical ventilation (MV).DesignProspective, randomized study.SettingA 24-bed medicosurgical intensive care unit in a 650-bed tertiary hospital.PatientsA total of 230 patients who needed MV for >24 hrs.InterventionsA total of 114 patients were ventilated with BF and 116 without BF.MeasurementsThroat swab and tracheal aspirate were taken at the moment of admission and twice a week until discharge. We considered the following infectious events: pneumonia, respiratory infection, which comprises pneumonia or tracheobronchitis, and respiratory colonization–infection complex, which comprises respiratory infection or colonization. All infectious events were classified as endogenous or exogenous based on throat flora.Main ResultsBoth groups of patients (ventilated with and without filters) were similar in age, sex, Acute Physiology and Chronic Health Evaluation II score, diagnostic group, days of MV, and mortality. There was no difference in the percentage of patients who developed pneumonia (24.56% with BF and 21.55% without BF), respiratory infection (33.33% vs. 28.44%), or colonization-infection (42.10% vs. 43.96%). The number of infectious events per 1000 days of MV were also similar in both groups: pneumonia (17.41 with BF and 16.26 without BF), respiratory infection (24.62 vs. 21.48), and colonization-infection (36.63 vs. 36). There were also no differences in incidence of infectious events by MV duration. Likewise, we did not find any differences in the number of exogenous events per 1000 days of MV: pneumonia, 2.40 with BF vs. 1.74 without BF; colonization-infection, 4.20 vs. 4.05.ConclusionsBacterial filters in ventilation circuits neither reduce the prevalence of respiratory infections associated with MV nor decrease exogenous infectious events; thus, their usage is not necessary.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveTo determine whether base excess, base excess caused by unmeasured anions, and anion gap can predict lactate in adult critically ill patients, and also to determine whether acid-base variables can predict mortality in these patients.DesignRetrospective study.SettingAdult intensive care unit of tertiary hospital.PatientsThree hundred adult critically ill patients admitted to the intensive care unit.InterventionsRetrieval of admission biochemical data from computerized records, quantitative biophysical analysis of data with the Stewart-Figge methodology, and statistical analysis.Measurements and Main ResultsWe measured plasma Na+, K+, Mg2+, Cl−, HCO3−, phosphate, ionized Ca2+, albumin, lactate, and arterial pH and Paco2. All three variables (base excess, base excess caused by unmeasured anions, anion gap) were significantly correlated with lactate (r2= .21,p< .0001; r2= .30,p< .0001; and r2= .31.p< .0001, respectively). Logistic regression analysis showed that the area under the receiver operating characteristic (AUROC) curves had moderate to high accuracy for the prediction of a lactate concentration >5 mmol/L: AUROC curves, 0.86 (95% confidence interval [CI], 0.78–0.94), 0.86 (95% CI, 0.78–0.93), and 0.85 (95% CI, 0.77–0.92), respectively.Logistic regression analysis showed that hospital mortality rate correlated significantly with Acute Physiology and Chronic Health Evaluation (APACHE) II score, anion gap corrected (anion gap corrected by albumin), age, lactate, anion gap, chloride, base excess caused by unmeasured anions, strong ion gap, sodium, bicarbonate, strong ion difference effective, and base excess. However, except for APACHE II score, AUROC curves for mortality prediction were relatively small: 0.78 (95% CI, 0.72–0.84) for APACHE II, 0.66 (95% CI, 0.59–0.73) for lactate, 0.64 (95% CI, 0.57–0.71) for base excess caused by unmeasured anions, and 0.63 (95% CI, 0.56–0.70) for strong ion gap.ConclusionsBase excess, base excess caused by unmeasured anions, and anion gap are good predictors of hyperlactatemia (>5 mmol/L). Acid-base variables and, specifically, “unmeasured anions” (anion gap, anion gap corrected, base excess caused by unmeasured anions, strong ion gap), irrespective of the methods used to calculate them, are not accurate predictors of hospital mortality rate in critically ill patients.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveIt has been postulated that in critically ill patients, splanchnic hypoperfusion may lead to cytokine release into the systemic circulation. The presence of cytokines could trigger an inflammatory response and cause multiple organ dysfunction syndrome. Although experimental studies support this hypothesis, humans studies remain controversial. The aim of the study was to determine the relationship between splanchnic hypoperfusion and cytokine release during septic shock.DesignHuman prospective study.SettingMedical intensive care unit at a university hospital.PatientsA total of 30 patients with mean arterial pressure of <60 mm Hg after volume loading with either oliguria or hyperlactatemia.MeasurementsGastric intramucosal measurements as an indicator of splanchnic hypoperfusion and blood samples were obtained at admission to the medical intensive care unit and repeated during 48 hrs. Cytokine (tumor necrosis factor-&agr; and interleukin-6) values were evaluated by enzyme-linked immunoassays at the following periods: at the time of admission and 2, 4, 8, 12, 24, 36, and 48 hrs later.Main ResultsHigh levels of interleukin-6 and tumor necrosis factor-&agr; were observed at admission in survivors and nonsurvivors, without significant difference. At 48 hrs, cytokine levels were significantly higher in patients who died compared with the survivors (tumor necrosis factor: 163 ± 16 for nonsurvivors vs. 34 ± 9 ng/mL for survivors; interleukin-6: 2814 ± 485 for nonsurvivors vs. 469 ± 107 ng/mL for survivors). At 48 hrs, the Pco2gap was significantly higher in the nonsurvivors compared with survivors (25.87 ± 2.73 vs. 11.35 ± 2.25 mm Hg), despite systemic hemodynamic variables in the normal range. A positive relationship was demonstrated between plasma levels of tumor necrosis factor-&agr; and interleukin-6 and the Pco2gap throughout the study. The Pco2gap was not correlated with hemodynamic variables.ConclusionsOur data suggest a relationship between gastric mucosal acidosis, as assessed by Pco2gap, and cytokine levels in critically ill patients with septic shock. Gut injury may be a contributor of the inflammatory response in patients with septic shock.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

ObjectiveThe aim of this study has been to investigate the factors predisposing to primary or secondary ventricular fibrillation (VF) and the prognosis in Spanish patients with acute myocardial infarction (AMI) during their admission to the intensive care unit or the coronary care unit.DesignA retrospective, observational study.SettingThe intensive care units and coronary care units of 119 Spanish hospitals.PatientsA retrospective cohort study including all the AMI patients listed in the ARIAM registry (Analysis of Delay in Acute Myocardial Infarction), a Spanish multicenter study. The study period was January 1995 to January 2001.Measurements and Main ResultsFactors associated with the onset of VF were studied by univariate analysis. Multivariate analysis was used to evaluate the independent factors for the onset of VF and for mortality. A total of 17,761 patients with AMI were included in the study; 964 (5.4%) developed VF (primary in 735 patients, secondary in 229). In multivariate analysis, the variables that continued to show an association with the development of VF were the Killip and Kimball class, peak creatine kinase, APACHE II score, age, and time from the onset of symptoms to the initiation of thrombolysis. The mortality in the patients with any VF was 31.8% (27.8% in patients with primary VF and 49.1% in patients with secondary VF). The development of VF is an independent predictive factor for mortality in patients with AMI, with a crude odds ratio of 5.12 (95% confidence interval, 4.41–5.95) and an adjusted odds ratio of 2.73 (95% confidence interval, 2.12–3.51).ConclusionsDespite the considerable improvement in the treatment of AMI in recent years, the onset of either primary or secondary VF is associated with a poor prognosis. It is usually accompanied by extensive necrosis.

ISSN:0090-3493    

出版商:OVID    

年代:2003

数据来源: OVID