ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectivesAssessment of left ventricular preload and left ventricular compliance changes in septic shock using pulmonary artery occlusion pressure (PAOP) presumes that this pressure accurately reflects left heart filling pressure. We tested the hypothesis that Starling resistor forces render PAOP inaccurate as an index of left heart filling pressure, resulting in misleading assessments of left ventricular compliance changes.DesignProspective, randomized, controlled study.SettingLarge-animal research laboratory at a university.SubjectsFourteen anesthetized domestic pigs weighing 20 to 25 kg.InterventionsPulmonary artery flotation catheters and systemic arterial catheters were placed via right cervical vessels. The left atrium was directly catheterized for left atrial pressure measurements. Left ventricular end-diastolic diameter was measured using sonomicrometry. Other measured or calculated variables were mean arterial pressure, mean pulmonary arterial pressure, PAOP, pulmonary capillary pressure, and pulmonary arterial and venous resistances. Pigs received endotoxin (0.5 mg/kg iv over 30 mins), or an equivalent volume of saline. At t = 60 mins, pigs were resuscitated with lactated Ringer's solution (40 mL/kg over 30 mins). Measurements were taken before and after endotoxin administration, and immediately and 30 mins after lactated Ringer's solution administration. Data were analyzed by two-way analysis of variance (p <or=to .05).Measurements and Main ResultsPAOP, mean pulmonary arterial pressure, and pulmonary capillary pressure increased after endotoxin infusion, while left atrial pressure and left ventricular end-dlastolic diameter decreased. Left atrial pressure and left ventricular end-diastolic diameter returned to baseline immediately after lactated Ringer's solution administration, while PAOP remained increased. Pulmonary arterial resistance and pulmonary venous resistance increased after endotoxin administration, with pulmonary venous resistance showing the greater percent increase. Pulmonary venous resistance decreased transiently immediately after lactated Ringer's solution administration. These changes were not observed in the control group. Accordingly, comparisons of PAOP vs. left ventricular end-diastolic diameter, and left atrial pressure vs. left ventricular end-diastolic diameter yielded divergent results.ConclusionsThe dissociation between PAOP and left atrial pressure, while left ventricular end-diastolic diameter (preload volume) decreased, and changes in pulmonary venous resistance, are strong evidence for Starling resistor forces (venocompression) rather than active venoconstriction. These data indicate that PAOP overestimates left atrial pressure during endotoxin shock, making it an inaccurate index of left ventricular preload. This overestimation can cause misleading assessments of left ventricular compliance.(Crit Care Med 1996; 24:1618-1625)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo describe the technology and nursing services that would be required to care for intensive care unit (ICU) low-risk monitor admissions in an intermediate unit.DesignProspective, multicenter, inception cohort analysis.Setting200 beds, including 26 hospitals that were randomly selected and 14 that volunteered for the study.PatientsA sample of 8,040 ICU patients admitted to the ICU for monitoring, who received no active life-support treatment on ICU day 1.InterventionsNone.Measurements and Main ResultsDemographic, physiologic, and treatment information were obtained during ICU days 1 to 7. A previously validated multivariate equation was used to identify 6,180 monitor admissions at low (<10%) risk for receiving active treatment during their entire ICU stay. We used daily Therapeutic Intervention Scoring System (TISS) data to identify the equipment, type and amount of nursing care, and the types of active treatment that would have been used had these ICU patients been admitted to an intermediate care unit. Mean day-1 ICU TISS scores were as follows: 16.4 for all patients; 18.3 for surgical patients; and 13.5 for medical admissions. Concentrated nursing care accounted for 89% and technologic monitoring for 11% of day-1 TISS points. Surgical admissions had a 2.8-day mean ICU length of stay and received an average of 16.5 TISS points per patient per day. Medical admissions had a 2.7-day mean ICU length of stay and received an average of 12.3 TISS points per patient per day. Subsequent active life-support therapy was received by 4.4% of these ICU low-risk monitor admissions.ConclusionsThe services received by ICU low-risk monitor admissions provide insight regarding the equipment and nursing care that might be required, and the kinds of emergencies that might occur, if these patients were cared for in medical and surgical intermediate care units. Our data suggest that if ICU low-risk monitor patients were admitted to an intermediate care unit, they would mainly require concentrated nursing care (nurse/patient ratio of 1:3 to 1:4) and limited technologic monitoring.(Crit Care Med 1996; 24:1626-1632)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectivesTo compare the outcomes for patients with one or more organ system failures treated in 1988 to 1990 with those outcomes from 1979 to 1982; to document risk factors for developing organ system failure; and investigate the relationship of these factors to hospital survival.DesignProspective, multicenter, inception cohort analysis.SettingSixty intensive care units (ICUs) at 53 U.S. hospitals.PatientsA total of 17,440 ICU admissions treated in 1988 to 1990 and 5,677 ICU admissions treated in 1979 to 1982.InterventionsNone.Measurements and Main ResultsAt the time of organ system failure, patients were classified by demographic, physiologic, and diagnostic information. The type and number of organ system failures and physiologic responses were recorded for <or=to7 days of ICU treatment, and all patients were followed for status at hospital discharge. Hospital survival and the prognostic value of assessing the number of organ system failures were compared with risk assessment, based on use of a prognostic scoring system that estimated the patient's probability of hospital mortality.The incidence of organ system failure (48%) among patients treated in 1988 to 1990 was similar (44%) to the occurrence rate in patients in 1979 to 1982; and an identical proportion (14%) developed multiple organ system failure.There was a significant (p <.0003) improvement in hospital mortality for patients with three or more organ system failures on day 4 or later of organ system failure. However, overall hospital mortality rates from multiple organ system failure were not different over this 8-yr period. The most important predictor of hospital mortality was the severity of physiologic disturbance on the initial day of failure. Discrimination of patients by risk of hospital mortality was better using the prognostic scoring system on day 1 of organ system failure (receiver operating characteristic curve = 0.88) than using a model based on the number of organ system failures (receiver operating characteristic curve = 0.68).ConclusionsOrgan system failure remains a major contributor to death in patients in ICUs. The incidence and overall outcome have not significantly changed over the past 8 yrs, but there has been significant improvement in survival for patients with persistent severe organ system failure. A continuous measure of individual patient severity of illness is a more sensitive and accurate method for describing patients and estimating outcome than counting the number of organ system failures.(Crit Care Med 1996; 24:1633-1641)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo assess the ability of the Acute Physiology and Chronic Health Evaluation (APACHE II) system and Trauma-Injury Severity Scoring (TRISS) system in predicting group mortality in intensive care unit (ICU) trauma patients.DesignProspective study.SettingA Canadian adult trauma tertiary referral hospital.PatientsConsecutive trauma patients admitted to the medical-surgical ICU or the neurosurgical ICU.InterventionNone.Measurements and Main ResultsFor each patient, demographic data, mechanism of injury, and surgical status were collected. Revised Trauma Scores and Injury Severity Scores were calculated from emergency room and operative data. The APACHE II score was calculated based on the data from the first 24 hrs of ICU admission. The probability of death was calculated for each patient based on the APACHE II and TRISS equations. The ability to predict group mortality for APACHE II and TRISS was assessed by receiver operating characteristic curve analysis, two by two decision matrices, and calibration curve analysis.Four hundred seventy trauma patients were admitted to the ICU.Sixty-three (13%) patients died and 407 (87%) survived. There were significant differences between survivors and nonsurvivors in age, Glasgow Coma Scale, Revised Trauma Score, Injury Severity Score, and APACHE II score. By receiver operating characteristic curve analysis, the areas under the curves (+/- SEM) of APACHE II and TRISS were 0.92 +/- 0.02 and 0.89 +/- 0.02, respectively. Using two by two decision matrices with a decision criterion of 0.5, the sensitivities, specificities, and percentages correctly classified were 50.8%, 97.3%, and 91.1%, respectively, for APACHE II, and 50.8%, 97.1%, and 90.9%, respectively, for TRISS. From the calibration curves, the r2value was .93 (p = .0001) for APACHE II and .67 (p = .004) for TRISS.ConclusionsBoth APACHE II and TRISS scores were shown to accurately predict group mortality in ICU trauma patients. APACHE II and TRISS may be utilized for quality assurance in ICU trauma patients. However, neither APACHE II nor TRISS provides sufficient confidence for prediction of outcome of individual patients.(Crit Care Med 1996; 24:1642-1648)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo determine xanthine oxidase activity, free radical concentrations, and lipid peroxidation in patients with sepsis syndrome compared with noninfected critically ill patients.DesignA prospective observational study.SettingA nine-bed intensive care unit in a university teaching hospital trust.PatientsFourteen consecutive patients who met the established criteria for sepsis syndrome with multiple organ dysfunction syndrome, and ten noninfected critically ill patients were studied.InterventionsNone.Measurements and Main ResultsXanthine oxidase activity was increased in septic patients compared with both healthy volunteers (p < .01) and noninfected patients (p < .05), and was highest in the six patients who survived (p < .05). Lipid peroxides were increased in both septic patients (p < .001) and nonseptic controls (p < .001). Xanthine oxidase activity did not relate to the Acute Physiology and Chronic Health Evaluation (APACHE) II score or to the presence of organ dysfunction. The mean ascorbyl radical concentration (arbitrary units) determined by electron paramagnetic resonance following spin trapping was increased in patients compared with healthy subjects (p < .05).ConclusionsPatients with sepsis have xanthine oxidase activation, high free-radical concentrations, and evidence of free radical damage. The finding that xanthine oxidase activity was lower in those patients who died, coupled with increased lactate concentrations implies more severe ischemia with incomplete reperfusion resulting in less xanthine oxidase "wash out" into the circulation. Increased ascorbyl radical concentrations may be due to an increased radical generation and oxidant scavenging, but appears to be unrelated to xanthine oxidase activity within the circulation.(Crit Care Med 1996; 24:1649-1653)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

ObjectiveTo examine intraoperative and postoperative lymphocyte adenylyl cyclase activities in children undergoing repair of congenital cardiac defects with hypothermic cardiopulmonary bypass.DesignA prospective study.SettingTertiary university pediatric hospital.PatientsTwelve children were enrolled into the study to examine intraoperative lymphocyte adenylyl cyclase activities and 12 children were enrolled to examine postoperative lymphocyte adenylyl cyclase activities.InterventionsNone.Measurements and Main ResultsBasal (unstimulated), isoproterenol, and prostaglandin E-1 stimulated adenylyl cyclase activities, and plasma norepinephrine and epinephrine concentrations were measured.Intraoperative basal (unstimulated), beta-adrenergic receptor-stimulated (in response to isoproterenol), and prostaglandin E1(PGE1)-stimulated lymphocyte adenylyl cyclase activities all increased during cardiopulmonary bypass, then decreased immediately after cardiopulmonary bypass. In the postoperative group, a significant decrease in basal (unstimulated), beta-adrenergic receptor- and PGE1-stimulated adenylyl cyclase activities were observed on postoperative day 1 as compared with precardiopulmonary bypass values.ConclusionsIn the pediatric cardiac surgical patient, there was an intraoperative enhancement of lymphocyte adenylyl cyclase activities. This increase in adenylyl cyclase activities was followed by reduced lymphocyte adenylyl cyclase activities, including beta-adrenergic receptor desensitization, postoperatively, as we have previously documented in adults.(Crit Care Med 1996; 24:1654-1659)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Objectivesa) To reduce the rate of catheter-related infection, using improved skin preparation and catheters impregnated with silver sulfadiazine and chlorhexidine; b) to decrease the number of unnecessary guidewire exchanges of existing catheters by substituting suspected catheter-related sepsis for fever alone as an indication to change an indwelling catheter; and c) to decrease the hospital costs associated with guidewire exchanges and new catheter insertions.DesignSequential, prospective, descriptive studies using a continuous quality management approach.SettingA 20-bed trauma intensive care unit at a university teaching hospital.PatientsPatients (n = 147) admitted from July 1 to December 31, 1992 (phase 1); 34 patients admitted in June and September 1993 (phase 2); and 156 patients admitted between January 1 and June 30, 1994 (phase 3).InterventionsPhase 1: Proportions of catheter-related infections and catheter-related bacteremia were compared with our prior reported results. Indications for guidewire exchange were analyzed, and the rate of catheter-related infection for each indication was derived. Phase 2: The rate of catheter-related infection was determined for a trial group of triple-lumen catheters impregnated with silver sulfadiazine and chlorhexidine. Phase 3: Four components were altered. Impregnated triple-lumen catheters were used instead of unprotected catheters. Chlorhexidine skin cleanser was substituted for povidone-iodine solution during initial aseptic preparation during catheter insertion and subsequent guidewire exchange. Suspected catheter-related sepsis was substituted for fever as an indication for guidewire exchange. The "safe" period (the time before considering changing a catheter because catheter-related sepsis was suspected) was extended from 2 to 4 days.Measurements and Main Results10 days compared with lesser durations. Fever was the indication for 42% of all guidewire exchanges. In phase 2, the catheter-related infection rate was 2% (one positive of 48 catheters), significantly (p = .0231) lower than the phase 1 rate. In phase 3, the overall rate of catheter-related infection was 8.6%, significantly (p = .0067) lower than the 15% rate in phase 1. The proportion of protected triple-lumen catheter catheter-related infections decreased significantly (p = .0024) from 15% to 6%. The rate of catheter-related infection for introducers was the same in both phases (p = .33). The days of catheterization for all catheters increased from 4.5 +/- 2.6 to 5.4 +/- 3.6 (p < .0001). The days for triplelumen catheters increased from 4.7 +/- 2.7 to 7.0 +/- 3.9 (p < .0001). For introducers, there was no difference in the days of catheterization. The proportion of catheters changed for suspected catheter-related sepsis decreased significantly (p < .0001) to 23% from the 42% changed for fever in phase 1. The proportion of catheter-related infections for catheters changed for fever was 18% in phase 1. The proportion of catheter-related infections for catheters changed for suspected catheter-related sepsis was 13% in phase 3 (p = .43). The total number of catheters used per patient in phase 3 was 1.9 +/- 1.4, significantly lower than the 2.6 +/- 2.7 catheters used in phase 1 (p = .0018). The number of triple-lumen catheters decreased from 1.8 +/- 1.2 to 1.0 +/- 1.2 in phase 3 (p = .0001).ConclusionsCatheters impregnated with silver sulfadiazine and chlorhexidine had a smaller proportion of catheter-related infection compared with unprotected catheters. Fever alone as an indication for guidewire exchange resulted in an increased number of unnecessary procedures. Using protected catheters and suspected catheter-related sepsis, together with an increase in the safe period before guidewire exchange, decreased the rate of catheter-related infection and increased the duration of catheterization. Together, these factors significantly decreased the number of catheters used for guidewire exchange and new catheter insertions per patient. The cost savings to the hospital were approximate $4,750 per month.(Crit Care Med 1996; 24:1660-1665)

ISSN:0090-3493    

出版商:OVID    

年代:1996

数据来源: OVID