摘要:

ObjectiveNo means exist for predicting the acute respiratory distress syndrome (ARDS), which complicates sepsis, trauma, and a variety of clinical disorders. Because activation of phospholipid-signaling pathways involving the acyl chains oleate and linoleate may initiate and amplify the inflammatory response, and thereby lead to the development of ARDS, we examined whether serum concentrations of these bioactive lipids increase and are predictive of ARDS in at-risk patients.DesignPart I: A prospective, single-blind trial. Part II: A prospective, randomized, double-blind trial.SettingGeneral intensive therapy units in five university teaching hospitals.SubjectsPart I: Thirty-nine healthy control patients were studied to determine normal distribution of serum acyl values, followed by 30 patients admitted with onset of sepsis, trauma, or development of ARDS (within 24 hrs of admission) over a 1-yr period. Part II: Eight patients admitted with sepsis syndrome over a 2-month period.InterventionsPart II: Patients were randomized to receive the substituted methylxanthine, lisofylline (CT1501R), or an identically presented placebo.Measurements and Main ResultsWe measured the serum free fatty acid concentrations in the 39 healthy control subjects, and then we prospectively examined the serum free fatty acid concentrations in 30 age-matched patients in samples obtained within 24 hrs from the onset of sepsis, trauma, or development of ARDS. We then prospectively studied eight septic, at-risk patients who were matched for age, Acute Physiology and Chronic Health Evaluation II scores, Multiple Organ Failure Index, and Glasgow Coma Score, in a double-blind, placebo-controlled, pilot study. These patients included four patients who received no treatment and four patients who received lisofylline, a compound that decreases serum unsaturated free fatty acids and diminishes acute lung injury in animals caused by sepsis and/or trauma. The calculated ratios of serum free fatty acids (i.e., the ratio of C18 unsaturated fatty acids linoleate and oleate to fully saturated palmitate, C16:0) increased and predicted the development of ARDS in at-risk patients. Serum samples from the 30 patients, obtained within 24 hrs from the onset of sepsis, trauma, or development of ARDS, had significantly increased mean acyl chain ratios (1.42 plus minus 0.35 [SD]) compared with healthy control subjects (0.86 plus minus 0.25; p less than .01). Sera from 13 patients with sepsis or trauma who did not develop ARDS (group A [at-risk, non-pre-ARDS]) also had increased acyl ratios (1.23 plus minus 0.27) compared with sera from healthy control subjects (0.86 plus minus 0.25; p less than .01). Sera from seven patients who subsequently developed ARDS (group B [at-risk, pre-ARDS]) had higher acyl ratios (1.70 plus minus 0.21) than group A at-risk patients who did not develop ARDS (1.23 plus minus 0.27; p less than .01) or healthy control subjects (0.86 plus minus 0.25; p less than .001). Sera from ten group C patients with ARDS at the time of admission to the study had the highest acyl ratios (1.80 plus minus 0.75), which exceeded values for healthy control subjects (p less than .001) and group A at-risk patients without ARDS (p equals .01), but were not significantly different than group B at-risk, pre-ARDS patients (p equals .17). Prospective study of eight septic, at-risk patients demonstrated significantly (p less than .05) increased serum acyl ratios in the four untreated patients (findings consistent with the first study) but a significantly (p equals .02) reduced ratio in the four at-risk patients treated with lisofylline.ConclusionsIncreases in unsaturated serum acyl chain ratios differentiate between healthy and seriously ill patients, and identify those patients likely to develop ARDS. Thus, the serum acyl ratio may not only prospectively identify and facilitate the assessment of new treatments in patients at highest risk for developing ARDS, but may also lead to new insights about the pathogenesis of ARDS.(Crit Care Med 1996; 24:1129-1136)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo examine the relationship of circulating proinflammatory and anti-inflammatory cytokine concentrations to nitric oxide and organ failure in pediatric sepsis.DesignProspective study.SettingPediatric intensive care unit (ICU), Children's Hospital of Pittsburgh, University of Pittsburgh.PatientsNineteen patients with a diagnosis of sepsis admitted to the pediatric ICU. Twelve uninfected critically ill patients served as controls.InterventionsNone.Measurements and Main ResultsPlasma interleukin (IL)-10, IL-6, and nitrite/nitrate concentrations were measured and compared with an index of organ failure daily for 3 days after presentation with the sepsis syndrome.Children with increased plasma IL-6 concentrations (n equals 6) had increased plasma nitrite/nitrate concentrations (p less than .01 on each day), increased organ failure scores (p less than .05 on days 2 and 3), and the highest plasma IL-10 concentrations (p less than .05 on days 1 and 3, p equals .054 on day 2) when compared with children with sepsis and undetectable IL-6 concentrations. Children with sepsis and detectable IL-6 concentrations, and children with undetectable IL-6 concentrations, both had increased nitrite/nitrate concentrations (p less than .005 on days 1 through 3) and increased IL-10 concentrations (p less than .05 on days 1 and 2) compared with controls. Children with increased IL-6 concentrations had higher organ failure on each day (p less than .01), and children with undetectable IL-6 concentrations had higher organ failure on days 1 and 2 only (p less than .005) when compared with controls. Organ failure improved over time in the children with undetectable IL-6 concentrations (p less than .005).ConclusionsIncreased plasma nitrite/nitrates and increased organ failure scores occurred in the children with sepsis who had an exaggerated proinflammatory state, despite a pronounced anti-inflammatory response. When the anti-inflammatory response predominated, and the proinflammatory state was dampened, organ failure status improved.(Crit Care Med 1996; 24:1137-1143)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo assess gastrointestinal permeability and functional absorptive capacity in patients with sepsis.DesignCase control study to analyze gastrointestinal permeability and functional absorptive capacity of septic patients by differential saccharide absorption (from an oral test solution) and excretion.SettingThe Intensive Therapy Unit of St. Thomas' Hospital, London, UK.PatientsTwenty patients with a mean Acute Physiology and Chronic Health Evaluation (APACHE) II score of 18.4 who were admitted to the intensive care unit with a diagnosis of sepsis. All patients were on enteral feeding. Patients with abdominal pathology were excluded.InterventionsAn oral test solution containing 5 g of lactulose, 1 g of L-rhamnose, 0.5 g of D-xylose, and 0.2 g of 3-O-methyl-D-glucose dissolved in water to a final volume of 100 mL was administered to patients and controls. Urine was collected for 5 hrs starting immediately after administration of the test solution and the saccharide content of the urine was estimated and expressed as a percentage recovery of the oral test solution.Measurements and Main ResultsSeptic patients had increased lactulose/L-rhamnose urine excretion ratios (0.23 plus minus 0.19) compared with control subjects (0.03 plus minus 0.01, p less than .001), consistent with increased gastrointestinal permeability in sepsis. Septic patients had decreased L-rhamnose/3-O-methyl-D-glucose urine excretion ratios (0.14 plus minus 0.07) compared with normal controls (0.28 plus minus 0.08, p less than .001), consistent with decreased gastrointestinal functional absorptive capacity in sepsis.ConclusionsPatients with acute sepsis exhibit increased gastrointestinal permeability and decreased gastrointestinal functional absorptive capacity in comparison with healthy control subjects. These abnormalities may contribute to the pathophysiology of sepsis.(Crit Care Med 1996; 24:1144-1149)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectivesTo characterize the effects of pressor doses of norepinephrine and low-dose dopamine (3 micro gram/kg/min) on renal hemodynamics in man, as well as to determine the clinical relevance of combining dopamine with norepinephrine.DesignProspective, single-blind, randomized study.SettingCLinical research unit of a tertiary care hospital.SubjectsSix healthy male volunteers ranging in age between 20 and 28 yrs.InterventionsThe subjects were assigned randomly to four treatments (1 wk apart) in which renal hemodynamics and electrolyte excretion were assessed. Treatments consisted of 180-min infusions of the following: a) 0.9% sodium chloride (control); b) pressor doses of norepinephrine; c) dopamine at 3 micro gram/kg/min; and d) pressor doses of norepinephrine and dopamine at 3 micro gram/kg/min. Pressor doses of norepinephrine were defined as doses required to increase mean arterial pressure (MAP) by 20 mm Hg.Measurements and Main ResultsGlomerular filtration rate and renal blood flow were derived from inulin and para-aminohippurate clearances, respectively. Urine output and urine solute excretion were also determined.The mean norepinephrine dose required to increase MAP by 22 plus minus 2 mm Hg was 118 plus minus 30 ng/kg/min (range 76 to 164). After the addition of dopamine, similar doses of norepinephrine resulted in an MAP increase of 15 plus minus 4 mm Hg. Glomerular filtration rate and urine output were comparable under all conditions. The infusion of norepinephrine decreased renal blood flow from 1241 plus minus 208 to 922 plus minus 143 mL/min/1.73 m2(p equals .03). The addition of dopamine returned renal blood flow to baseline values. The clearance of urine sodium increased significantly with the infusion of dopamine alone (p equals .03). All subjects completed the four treatment periods. Adverse events, manifested mostly as palpitations and flushing, were rare and self-limiting.ConclusionsThe addition of dopamine (3 micro gram/kg/min) to pressor doses of norepinephrine normalized renal blood flow in healthy volunteers. These hemodynamic changes were not reflected in urine output and glomerular filtration rate; hence, these monitoring parameters may be unreliable indicators of renal function in the setting of vasopressor therapy. In addition, systemic effects were observed with dopamine (3 micro gram/kg/min), as indicated by a decrease in MAP.(Crit Care Med 1996; 24:1150-1156)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectivesTo compare microbial contamination of two different blood conservation devices; to determine if there was an association between contamination of the blood conservation devices and clinical infections; to determine if there was a significant user preference for either of the two devices.DesignProspective, randomized trial.SettingMedical, neurosurgical, and spinal cord intensive care units of an urban, university hospital.PatientsForty patients who required clinically indicated intra-arterial catheters placed at new sites.InterventionsThe two most widely available blood conservation devices at the time of the study (Venous Arterial blood Management Protection system Trademark [VAMP], Baxter Edwards Critical-Care, Irvine, CA; and Safe Draw Trademark, Ohmeda, Madison, WI) were chosen for comparison. After the normal 48 to 72 hrs of device use, the blood conservation systems were removed and semiquantitative and quantitative cultures were taken from comparable sites of the two devices. Positive cultures from the patients were recorded and correlated with cultures obtained from the devices. In order to assess preference for either device, a survey tool was administered to the nursing staff who participated in the study.Measurements and Main ResultsQuantitative cultures from all sites cultured in both groups demonstrated mean colony counts of less than 103colony-forming units (cfu)/mL. There were no statistically significant differences in the colony counts at any of the sites compared between the two groups. There were no statistically significant relationships between positive cultures and patient age, gender, duration of device utilization, frequency of device entry, or the intensive care unit in which the study was conducted. In no circumstance did positive cultures from any of the blood conservation devices correlate with positive culture results from any sites of clinical infection. The clinical survey demonstrated a statistically significant preference for the VAMP system, which persisted despite increased experience with the Safe Draw system.ConclusionsThe levels of microbial contamination noted in these devices were not consistent with clinical infection (defined as 103cfu/mL on quantitative cultures). There was no significant difference in degree or pattern of contamination between the two devices. When utilized and changed according to the Centers for Disease Control guidelines, blood conservation devices are not harbors of infection in the critical care setting. Blood conservation devices can be used as part of a comprehensive blood conservation program in the critical care setting without undue concern for exacerbating infectious processes.(Crit Care Med 1996; 24:1157-1162)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo compare point-of-care results obtained from an on-site hemocytometer with values provided by an institutional laboratory instrument.DesignA prospective laboratory evaluation.SettingThe central laboratory and cardiac surgical intensive care unit of a university-affiliated tertiary care center.PatientsNormal range comparison was performed using blood specimens routinely obtained from 48 hospitalized patients for complete blood count analysis. The second evaluation was performed on blood specimens routinely obtained (in the intensive care unit) after cardiac surgery involving extracorporeal circulation in a series of 187 consecutive patients.Measurements and Main ResultsHemoglobin concentration, platelet count, mean corpuscular volume, mean platelet volume, and red and white blood cell counts were measured with both on-site (MD 16, Coulter Electronics, Hialeah, FL) and laboratory (STKS, Coulter Electronics) instruments. Hematocrit and red cell distribution width were calculated using measured variables. Blood specimens were obtained from two distinct patients series. To evaluate measurement values within the normal range, a series of 48 routinely obtained blood specimens for complete blood count analysis in our institutional laboratory were utilized for concurrent analysis with the on-site hemocytometer. To evaluate measurement values out of the normal range, a second comparison involved measurements performed on blood specimens obtained in the cardiac surgical intensive care unit for complete blood count analysis. Linear regression demonstrated good correlations between on-site and laboratory hemoglobin concentration (r2equals .97), hematocrit (r2equals .95), platelet count (r2equals .97), mean corpuscular volume (r2equals .91), red cell distribution width (r2equals .80), and red (r2equals .95) and white (r2equals .96) blood cell count results. A marginal correlation was observed between mean platelet volume values (r2equals .47). Bias analysis (mean plus minus 2 SD) demonstrated similar measurements between on-site and laboratory hemoglobin concentration, hematocrit, platelet count, red blood cell count, white blood cell count, mean platelet volume, mean corpuscular volume, and red cell distribution width.ConclusionsOn-site hemoglobin concentration, hematocrit, white blood cell count, red blood cell count, red cell distribution width, and platelet count values compare well with those results obtained from the laboratory. The MD 16 hemocytometer (Coulter Electronics) provides on-site hematologic results that can provide an accurate and rapid quantitative assessment of platelets, and red and white blood cells. Rapid access to information obtained from this type of system may be clinically useful, especially in critically ill patients.(Crit Care Med 1996; 24:1163-1167)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo cost adult intensive care by determining inputs to production, resource consumption per patient, and total cost per intensive care unit (ICU) stay.DesignProspective cost-accounting analysis of each patient stay in the ICU, over a 1-yr period.SettingAn 11-bed, medical/surgical adult ICU, in a 932-bed urban teaching hospital.PatientsAll patients' admissions to an adult ICU over a 1-yr period, excluding those patients admitted solely for repeat hemodialysis.InterventionsNone.Measurement and Main ResultsDemographic information was collected, including age, gender, Acute Physiology and Chronic Health Evaluation (APACHE) II score, primary reason for ICU admission, operative (elective and emergency) and nonoperative status, ICU length of stay, and ICU outcome.Direct patient care costs were accounted to individual patients whose care generated those costs, and indirect patient care costs were averaged over all patients in the ICU on a daily basis. Costs were collected for human (nursing, medical, professional, and support staff) and capital (laboratory, diagnostic imaging, supplies, drugs, and equipment) resources.Cost information was available on 690 patients (43% female, 57% male). Cost/day/patient was $1,508 plus minus 475 (1992 Canadian dollars) and the average cost per ICU stay was $7,520 plus minus 11,606. Median cost/stay for all patients was $2,600. Cost per ICU stay was less than $5,000 in 68% of patients, with an ICU survival rate of 85%. High cost was not a marker for poor survival. There was no relationship between age and cost categories. Across most diagnoses, cost/day/patient was remarkably constant, approximating $1,500/day/patient at existing labor rates.ConclusionsIn order to develop strategies aimed at cost containment, it is first necessary to undertake a thorough examination of cost drivers. This detailed cost-accounting study determined inputs to production, resources consumed by individual patients, and costs incurred during ICU stay.(Crit Care Med 1996; 24:1168-1172)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectivesWe tested the hypothesis that heatstroke is associated with endothelial cell activation/injury and examined the possibility that the markers of endothelial cell activation/injury may be associated with its severity and complications such as disseminated intravascular coagulation, lung injury, and renal dysfunction.DesignProspective analyses.SettingHeatstroke Center in Makkah, Saudi Arabia.PatientsTwenty-two adult patients with heatstroke.InterventionsThe plasma concentration of endothelin, circulating intercellular adhesion molecule-1 (ICAM-1), and von Willebrand factor-antigen values were measured, respectively, by radioimmunoassay, enzyme-linked immunosorbent assay, and rocket electroimmunoassay, in heatstroke patients on admission (precooling) and after complete cooling (postcooling), and in ten normal control patients.Measurements and Main ResultsPrecooling heatstroke patients (rectal temperature 40.9 plus minus 1.1 [SD] degrees C) had increased circulating concentrations of endothelin, c-ICAM-1, and von Willebrand factor-antigen in 100%, 80%, and 77% of patients to 126.4 plus minus 11.2 pmol/L, 523.1 plus minus 154.4 ng/mL, and 3.85 plus minus 2.3 U/mL, respectively (control values: 13.7 plus minus 4.2 pmol/L [p less than .001]; 247.4 plus minus 68.2 ng/mL [p less than .001]; and less than 1.5 U/mL, respectively). There was a significant (r2equals .68, p less than .01) correlation between circulating ICAM-1 and endothelin concentrations. Plasma endothelin concentration correlated negatively with temperature (r2equals .35, p less than .05). Mean endothelin concentration was similar in patients with or without renal dysfunction, and mean von Willebrand factor-antigen concentration was similar in patients with or without lung injury or disseminated intravascular coagulation. There were no significant correlations between circulating ICAM-1, endothelin, or von Willebrand factor-antigen concentration and the Simplified Acute Physiology core. After cooling, mean circulating ICAM-1 and endothelin concentrations decreased significantly to 400 plus minus 109 ng/mL and 93 plus minus 38.5 pmol/L, respectively, whereas the mean von Willebrand factor-antigen concentration increased to 5.55 plus minus 2.18 U/mL (p more than .05).ConclusionsOur findings of increased circulating concentrations of circulating ICAM-1, endothelin, and von Willebrand factor-antigen are consistent with the hypothesis that heatstroke is associated with endothelial cell activation/injury. Whether the endothelial cell activation/injury is implicated in the pathophysiology of this disorder merits further studies.(Crit Care Med 1996; 24:1173-1178)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine the plasma antioxidant potential of patients in the intensive care unit (ICU) with severe sepsis and secondary organ dysfunction and relate these findings to outcome.DesignA prospective, cohort study.SettingA nine-bed ICU in a university teaching hospital.PatientsFifteen consecutive patients, who were within 18 hrs of development of severe sepsis and secondary organ dysfunction.InterventionsPlasma samples were obtained within 18 hrs of the onset of secondary organ dysfunction and subsequently on days 2, 3, 4, 6, 8, 10, and 15 until patients either left the ICU or died. Plasma antioxidant potential was determined by an ultraviolet spectrophotometric technique.Measurements and Main ResultsThe mean initial plasma antioxidant potential was lower than our range for healthy volunteers (p less than .05). Survivors had an initial plasma antioxidant potential that was greater than nonsurvivors (p less than .01), and serial subset analysis demonstrated that survivors, despite having a low initial plasma antioxidant potential rapidly attained normal or supranormal values. While plasma antioxidant potential also increased in nonsurvivors over time, values in this subset never reached the normal range and remained below values in survivors at all time points studied (p less than .05).ConclusionsPlasma antioxidant potential is initially decreased in patients with sepsis who develop organ dysfunction, and it increases over time. While we have no clear evidence to prove that this reduction has a causal relationship, failure to achieve a normal plasma antioxidant potential is strongly associated with an unfavorable outcome.(Crit Care Med 1996; 24:1179-1183)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo evaluate the effect of two commonly used heat and moisture exchangers on respiratory function and gas exchange in patients with acute respiratory failure during pressure-support ventilation.DesignProspective, randomized trial.SettingIntensive care unit of a university hospital.PatientsFourteen patients with moderate acute respiratory failure, receiving pressure-support ventilation.InterventionsPatients were assigned randomly to two treatment groups, in which two different heat and moisture exchangers were used: Hygroster Registered Trademark (DAR S.p.A., Mirandola, Italy) with higher deadspace and lower resistance (group 1, n equals 7), and Hygrobac-S Registered Trademark (DAR S.p.A.) with lower deadspace and higher resistance (group 2, n equals 7). Patients were assessed at three pressure-support levels: a) baseline (10.3 plus minus 2.4 cm H2O for group 1, 9.3 plus minus 1.3 cm H2O for group 2); b) 5 cm H2O above baseline; and c) 5 cm H2O below baseline. Measurements obtained with the heat and moisture exchangers were compared with those values obtained using the standard heated hot water humidifier.Measurements and Main ResultsAt baseline pressure-support ventilation, the insertion of both heat and moisture exchangers induced in all patients a significant increase in the following parameters: minute ventilation (12.4 plus minus 3.2 to 15.0 plus minus 2.6 L/min for group 1, and 11.8 plus minus 3.6 to 14.2 plus minus 3.5 L/min for group 2); static intrinsic positive end-expiratory pressure (2.9 plus minus 2.0 to 5.1 plus minus 3.2 cm H2O for group 1, and 2.9 plus minus 1.7 to 5.5 plus minus 3.0 cm H2O for group 2); ventilatory drive, expressed as P0.1 (2.7 plus minus 2.0 to 5.2 plus minus 4.0 cm H2O for group 1, and 3.3 plus minus 2.0 to 5.3 plus minus 3.0 cm H2O for group 2); and work of breathing, expressed as either power (8.8 plus minus 9.4 to 14.5 plus minus 10.3 joule/min for group 1, and 10.5 plus minus 7.4 to 16.8 plus minus 11.0 joule/min for group 2) or work per liter of ventilation (0.6 plus minus 0.6 to 1.0 plus minus 0.7 joule/L for group 1, and 0.8 plus minus 0.4 to 1.1 plus minus 0.5 joule/L for group 2). These increases also occurred when pressure-support ventilation was both above and below the baseline level, although at high pressure support the increase in work of breathing with heat and moisture exchangers was less evident. Gas exchange was unaffected by heat and moisture exchangers, as minute ventilation increased to compensate for the higher deadspace produced in the circuit by the insertion of heat and moisture exchangers.ConclusionsThe tested heat and moisture exchangers should be used carefully in patients with acute respiratory failure during pressure-support ventilation, since these devices substantially increase minute ventilation, ventilatory drive, and work of breathing. However, an increase in pressure-support ventilation (5 to 10 cm H sub 2 O) may compensate for the increased work of breathing.(Crit Care Med 1996; 24:1184-1188)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID