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A method for fault detection and isolation is developed using the concatenated variances of the continuous wavelet transform (CWT) of plant outputs. These concatenated variances are projected onto the principal component space corresponding to the covariance matrix of the concatenated variances. Fisher and quadratic discriminant analyses are then performed in this space to classify the concatenated sample CWT variances of outputs in a given time window. The sample variance is a variance estimator obtained by taking the displacement average of the squared wavelet transforms of the current outputs. This method provides an alternative to the multimodel approach used for fault detection and identification, especially when system inputs are unmeasured stochastic processes, as is assumed in the case of the mechanical system example. The performance of the method is assessed using matrices having the percentage of correct condition identification in the diagonal and the percentages misclassified conditions in the off-diagonal elements. Considerable performance improvements may be obtained due to concatenation—when two or more outputs are available—and to discriminant analysis, as compared with other wavelet variance methods. [ABSTRACT FROM AUTHOR]

Objective: To identify objective trends of the course of illness that might be used as benchmarks in the auditing of the organization/performance of Intensive Care Units (ICU).Design: Retrospective analysis.Patients and Setting: A group of 12,615 patients and 55,464 patient-days prospectively collected in 89 ICUs of 12 European countries.Methods: The complexity of daily care in the ICU was classified as high (HT) or low (LT), according to six activities registered in NEMS,a daily therapeutic index for ICUs.Results: Six trends of clinical course were identified: LT during the whole ICU stay (5,424 patients, mortality 1.8%); HT (3,480 patients, mortality 30.4%); HT followed by LT (2,781 patients, mortality 2.8%); LT followed by HT (197 patients, mortality 39.1%); finally, LT/HT/LT in 298 patients (mortality 10.5%); and HT/LT/HT (mortality 20.1%) in 438 patients. A group of 930 patients had the complexity of treatment increased (mortality 21.1%) and 3,711 patients received both treatments. Low-care before high-care periods had a mean duration of 2.2 +/- 3.5 days, low-care after high-care 2.7 +/- 3.1 days, and between two high-care periods 2.1 +/- 2.2 days. A group of 1,538 'surgical scheduled' patients only received LT, whereas 2,231 received HT (whether or not exclusively). Overall ICU mortality rate was low (3%) and the length of stay short, regardless of diagnosis and complexity of care received.Conclusions: The use of therapeutic indexes help to classify the daily complexity of ICU care. The classification can be used as an indicator of clinical performance and resource utilization. [ABSTRACT FROM AUTHOR]

Objectives: Mortality after ICU discharge accounts for approx. 20-30% of deaths. We examined whether post-ICU discharge mortality is associated with the presence and severity of organ dysfunction/failure just before ICU discharge.Patients and Methods: The study used the database of the EURICUS-II study, with a total of 4,621 patients, including 2,958 discharged alive to the general wards (post-ICU mortality 8.6%). Over a 4-month period we collected clinical and demographic characteristics, including the Simplified Acute Physiology Score (SAPS II), Nine Equivalents of Nursing Manpower Use Score, and Sequential Organ Failure Assessment (SOFA) score.Results: Those who died in the hospital after ICU discharge had a higher SAPS II score, were more frequently nonoperative, admitted from the ward, and had stayed longer in the ICU. Their degree of organ dysfunction/failure was higher (admission, maximum, and delta SOFA scores). They required more nursing workload resources while in the ICU. Both the amount of organ dysfunction/failure (especially cardiovascular, neurological, renal, and respiratory) and the amount of nursing workload that they required on the day before discharge were higher. The presence of residual CNS and renal dysfunction/failure were especially prognostic factors at ICU discharge. Multivariate analysis showed only predischarge organ dysfunction/failure to be important; thus the increased use of nursing workload resources before discharge probably reflects only the underlying organ dysfunction/failure.Conclusions: It is better to delay the discharge of a patient with organ dysfunction/failure from the ICU, unless adequate monitoring and therapeutic resources are available in the ward. [ABSTRACT FROM AUTHOR]

Objective: To develop a simple and comparable clinical method able to distinguish between higher and lower complexities of care in the ICU.Design: Retrospective analysis.Setting: Database of European ICUs Study I (Euricus-I: including 12,615 patients and 55,464 patient/days), prospectively collected in 89 ICUs of 12 European countries.Methods and Results: A panel of experts developed the classification of the complexity of care. Six (in addition to monitoring, two levels of respiratory support--R and r--two levels of circulatory support--C and c--and dialysis) out of the nine items of Nine Equivalents of Nursing Manpower use Score (NEMS), a therapeutic index, were utilised. Two levels of care (LOCs) were defined according to a more (HT) and a less complex (LT) combination of common activities of care. The two LOCs were significantly related to mortality: higher in HT and they rose with increasing cumulative number of HT days. HT accounted for 31,976 NEMS days (57.7%) while 23,488 (42.3 %) were LT. Major respiratory and cardiovascular support accounted for about 80 % of the HT days. Respiratory assistance and monitoring were responsible for an equivalent percentage of LT days. The distribution of the clinical classification of LOCs coincided with that of the managerial scores of LOCs in the literature.Conclusions: The managerial instrument described uses simple and reliable clinical data. It is able to distinguish between patients with different severity and outcome, and shows that every additional consecutive day spent in ICU as HT increases the probability of death. Moreover, (1) it suggests the possibility of describing the clinical course of illness by relating the complexity/level of medical care to the available technology and staff; (2) using relevant markers of clinical activity, it might be useful to include in quality control programmes. [ABSTRACT FROM AUTHOR]

In a control group of 59 multiple trauma patients requiring prolonged intensive care, a conventional restrictive antibiotic policy was followed. Forty-eight patients (81%) developed 94 infections. Fifty-one patients received systemic antibiotic therapy with one or more drugs. The total quantity of systemic antibiotics used was very high (18.3±22.1 antibiotic days per patient). This policy resulted in a very high incidence of superinfections (24%) with multiply-resistant Gram-negative bacteria, mostly emerging from the digestive tract (secondary endogenous infections). Five patients died from infection.A novel technique of infection prevention, based on the maintenance of the colonization resistance and on selective decontamination of the digestive tract in combination with systematic antibiotic prophylaxis with cefotaxime, proved to be very effective. Out of 63 multiple trauma patients, intubated and ventilated for 5 days or more in the ICU, 10(16%) developed 11 infections. Most infections occurring under this regimen were primary endogenous infections which were treated by continuation of cefotaxime. Only two patients (3%) developed a superinfection with cefotaximeresistant Gram-negative bacteria. No patient died. This approach to infection prevention in the ICU, shows that prophylactic administration of antibiotics significantly reduced the infection rate of critically ill patients without the development of superinfection. [ABSTRACT FROM PUBLISHER]

Objective: To compare the performance of the New Simplified Acute Physiology Score (SAPS II) and the New Admission Mortality Probability Model (MPM II0) within relevant subgroups using formal statistical assessment (uniformity of fit).Design: Analysis of the database of a multi-centre, multi-national and prospective cohort study, involving 89 ICUs from 12 European Countries.Setting: Database of EURICUS-I.Patients: Data of 16,060 patients consecutively admitted to the ICUs were collected during a period of 4 months. Following the original SAPS II and MPM II0 criteria, the following patients were excluded from the analysis: younger than 18 years of age; readmissions; acute myocardial infarction; burn cases; patients in the post-operative period after coronary artery bypass surgery and patients with a length of stay in the ICU shorter than 8 h, resulting in a total of 10,027 cases.Interventions: Data necessary for the calculation of SAPS II and MPM II0, basic demographic statistics and vital status on hospital discharge were recorded. Formal evaluation of the performance of the models, comprising discrimination (area under ROC curve), calibration (Hosmer-Lemeshow goodness-of-fit H and C tests) and observed/expected mortality ratios within relevant subgroups.Main Results: Better predictive accuracy was achieved in elective surgery patients admitted from the operative room/post-anaesthesia room with gastrointestinal, neurological or trauma diagnoses, and younger patients with non-operative neurological, septic or trauma diagnoses. All these characteristics appear to be linked to a lower severity of illness, with both models overestimating mortality in the more severely ill patients.Conclusions: Concerning the performance of the models, very large differences were apparent in relevant subgroups, varying from excellent to almost random predictive accuracy. These differences can explain some of the difficulties of the models to accurately predict mortality when applied to different populations with distinct patient baseline characteristics. This study stresses the importance of evaluating multiple diverse populations (to generate the design set) and of methods to improve the validation set before extrapolations can be made from the validation setting to new independent populations. It also underlines the necessity of a better definition of the patient baseline characteristics in the samples under analysis and the formal statistical evaluation of the application of the models to specific subgroups. [ABSTRACT FROM AUTHOR]

Objectives: a) to validate the structure of the Sickness Impact Profile scale (SIP) when applied to intensive care patients after discharge from the hospital; b) to explore the influence of age upon the various components of quality of life.Design: Prospective study.Setting: Patients admitted to 36 Dutch ICUs.Methods: 6,247 patients out of 13,000 consecutive admissions to the ICUs answered a SIP questionnaire 6 months after discharge from the hospital. The 3,655 returned questionnaire were analyzed after aggregating the respondents into 6 age groups: from group 1: 17-29 up to group 4: > 70 years of age.Intervention: Self-administration of SIP one year after discharge, measuring 5 independent categories (IC) and two dimensions: physical (PD) and psychosocial (PSD).Results: The total SIP-score oscillated between 5.8 +/- 8.2 (group I) and 10.5 +/- 9.5 (group 4). Group 3 had also a high score (9.4 +/- 11.2). Overall, the quality of life of patients was dominated by dysfunction on the categories composing the physical dimension, with exception of patients with ages between 30 and 50 years, in which dysfunction on the categories composing the psychosocial dimension was dominant. The structure of the SIP in the study was similar to that described to the original instrument.Conclusions: The study validated the use of the SIP QOL-instrument on patients after intensive care. Age influenced consistently the various components of quality of life. [ABSTRACT FROM AUTHOR]

Nursing costs more than any other element of intensive care. Nurses are allocated exclusively to the ICU, and their use can therefore be accurately monitored. The amount of nursing work in the ICU is intimately associated with the severity of illness of the patients. Consequently, the density of nursing staff in the ICU can be used as a measure of cost, and the Therapeutic Intervention Scoring System (TISS) is a reliable tool for measuring their workload. TISS is therefore often used to compare the costs of alternative courses of care; it covers direct costs of care, but it should not be used as a proxy for total costs in the ICU. The users of TISS should consider the limitations of the scoring system in some aspects of its development, as well as the general nature of the definitions of the items included. The careful enunciation of the more generally defined items has therefore to be considered when it is used in a research project that compares small samples.

Objective: To evaluate the performance of the New Simplified Acute Physiology Score (SAPS II) and the admission Mortality Probability Model (MPM0) in a large independent database, using formal statistical assessment., Design: Analysis of the database of a multicenter, multinational, prospective cohort study, EURICUS-I., Setting: Eighty nine intensive care units (ICUs) from 13 European areas., Patients: Data of 16,060 patients consecutively admitted to the participating ICUs were collected during a period of 4 months. Following the original SAPS II and MPM0 criteria, the analysis excluded: patients <18 ys of age; readmissions; patients admitted with acute myocardial infarction; burns; and patients in the postoperative period after coronary artery bypass surgery. All patients with a length of stay <8 hrs were excluded from the study to keep comparability between both systems. A total of 10,027 patients were analyzed., Interventions: Collection of the first 24 hrs' admission data necessary for the calculation of SAPS II and MPM0 and basic demographic statistics. Vital status at discharge from the hospital was registered., Measurements and Main Results: Despite having a good discriminative capability, as measured by the area under the receiver operating characteristic (ROC) curves (SAPS II: ROC = 0.822 +/- 0.005 SEM; MPM0: ROC = 0.785 +/- 0.006 SEM), both models presented poor calibration, with significant differences between observed and predicted mortality (Hosmer-Lemeshow goodness-of-fit tests H and C, p < .0001). Both SAPS II (predicted risk >40%) and MPM0 (predicted risk >30%) overestimated the risk of death. The evaluation of the uniformity of fit of SAPS II and MPM0 demonstrated large variations across the various subgroups of patients., Conclusions: The original SAPS II and MPM0 models did not accurately predict mortality on an independent large international multicenter ICU patient database. Results of studies utilizing general outcome prediction models without previous validation in the target population should be interpreted with prudence.

Objective: To assess and to follow along the time-span of ICU stay the process of resources allocation and utilization., Design: Prospective study., Patients: A cohort of 778 patients consecutively admitted to 7 multipurpose general ICU in the Milano area were enrolled in a survey of the daily performed interventions/procedures., Measurements and Main Results: The majority of diagnostic procedure/interventions were performed during the first two days. The number and quality of interventions were transferred into points obtaining a score system in non-monetary units. The resource allocation process shows a regular trend in the sub-intensive patients who were only monitorized. On the contrary the 258 patients who were intensively treated and survived show a phase of high resource-consumption (about 30 daily points: roughly twice the score of monitorized patients) then followed by a post-intensive phase with a resource consumption resulting in a daily score absolutely equal to the sub-intensive patients. The intensive patients who die show a significantly higher score than survived patients. Both daily and cumulative scores do not show differences among different type of patients., Conclusion: The evaluation of the process of resources allocation, even if in non-monetary units enables the knowledge of the trend of ICU costs and allows the elaboration of the appropriate budget mechanism.

Objectives: To validate a simplified version of the Therapeutic Intervention Scoring System, the TISS-28, and to determine the association of TISS-28 with the time spent on scored and nonscored nursing activities., Design: Prospective, multicenter study., Setting: Twenty-two adult medical, surgical, and general Dutch intensive care units (ICUs)., Patients: A total of 903 patients consecutively admitted to the ICUs., Interventions: TISS-28 was constructed from a random sample of 10,000 records of TISS-76 items. The respective weights were calculated using multivariable regression analysis through the origin; TISS-76 scores were used as predicted values. Cross validation was performed in another random sample of 10,000 records and the scores of TISS-76 were compared with those scores obtained with TISS-28 (r = .96, r2 = .93). Nursing activities in the ICU were inventoried and divided into six categories: a) activities in TISS-28; b) patient care activities not in TISS-28; c) indirect patient care (activities related to but not in direct contact with the patient, such as contact with family, maintaining supplies); d) organizational activities (e.g., meetings, trainee supervision, research); e) personal activities (for the nurse him/herself, such as taking a break, going to the bathroom); f) other. During a 1-month period, TISS-76 and TISS-28 scores were determined daily from the patient's records by independent raters. During a 1-wk period, all of the nurses on duty scored their activities using a method called "work sampling.", Measurements and Main Results: The analysis of validation included 1,820 valid pairs of TISS-76 and TISS-28 records. The mean value of TISS-28 (28.8 +/- 11.1) was higher (p < .00) than that value of TISS-76 (24.2 +/- 10.2). TISS-28 explained 86% of the variation in TISS-76 (r = .93, r2 = .86). "Work sampling" generated 10,079 registrations of nursing activities, of which 5,530 could be matched with TISS-28 records. Samples were taken from medical (19.3%), surgical (19.1%), and general (61.6%) ICUs. Of these samples, 51.1% originated from university hospitals, 35.8% from hospitals with > 500 beds, 7.1% from hospitals with 300 to 500 beds, and 5.8% from hospitals with < 300 beds. Samples were scored in the morning (43.0%), evening (32.9%), and night shifts (24.1%). This sample of work activities was divided into four groups, according to their matched TISS scores (0 to 20, 20 to 35, 35 to 60, and > 60 points). In the successive groups of TISS scores, there was a significant increase in the proportion of time spent on the activities scored with TISS-28. In the lower TISS score group (0 to 20 points), there was a significantly larger proportion of time allocated to patient care activities not in TISS-28. There was no significant difference in the proportion of the time spent when associating indirect patient care and organizational activities with the level of TISS score. There was a significant decrease in the proportion of time spent on personal activities in the successive groups of TISS scores. The mean time spent per shift with personal activities varied between 1 hr and 40 mins (group 0 to 20 points TISS), and 1 hr and 16 mins (group > 60 points TISS). Significantly more time was used for patient care activities during the evening shift than during the day or the night shift. Conversely, nurses spent significantly less time on activities regarding their personal care during the evening shift. The time consumed for the activities of indirect patient care did not differ significantly among the three shifts. A typical nurse was capable of delivering work equal to 46.35 TISS-28 points per shift (one TISS-28 point equals 10.6 mins of each nurse's shift)., Conclusions: The simplified TISS-28 explains 86% of the variation in TISS-76 and can therefore replace the original version in the clinical practice in the ICU. Per shift, a typical nurse is capable of delivering nursing activities equal to 46 TISS-28 points.

Objectives: This study evaluates the influence of Cardiopulmonary Resuscitation (CPR) on the components of quality of life (QOL) of patients after discharge from the hospital., Design: Extracted from a prospective national survey on Dutch intensive care units (ICUs)., Setting: Thirty-six ICUs of both university and nonuniversity hospitals, spread throughout the country., Methods: For a period of 6 months, 9,803 consecutive ICU admissions entered the study. Outcome in connection with in-hospital CPR was analyzed by comparing the CPR group (n = 477) with a standardized control group without CPR (n = 500)., Interventions: Activities of daily living were registered at the time of hospital admission. A record was kept of each patient for demographics, severity of illness, length of stay, daily use of manpower and ICU technology, and mortality. Six months after hospital discharge, the QOL of 69 patients in both the CPR and control groups was measured with the Sickness Impact Profile (SIP)., Results: CPR was performed in 4.8 percent of the patients, mainly from the general ward. These patients were older, had a higher severity of illness, and a higher daily consumption of nursing resources. The QOL did not correlate with severity of illness on admission, length of stay, or consumption of resources in the ICU. On the whole, the SIP scores of both CPR and control groups did not differ much: 11.7 vs 10.7, and circulatory arrest did not appear to impair the self-sufficiency in the study group significantly in comparison with the controls. An increased dysfunction was found in the CPR group of patients concerning their work and their psychosocial functioning., Conclusion: Patients who have recovered from a circulatory arrest after CPR resuscitation find their capacity for resuming work diminished after discharge from the hospital, while they seem to experience a postponed negative effect on their mental functioning, especially the functions connected with the awareness of their environment.

In The Netherlands, 8.3% of the gross national product is allocated to health care. Medical care provided in ICUs consumes approximately 8% of hospital budgets, or approximately 2.5% of the total healthcare budget. The high cost of intensive care medicine in The Netherlands has become a matter of concern during the last decade. A national intensive care study was conducted from 1989 through 1990 to evaluate the effectiveness and organization of ICUs in the country. This study has shown that there is an association between the operational characteristics of ICUs and the hospital in which these units operate. In approximately 50% of ICUs studied, a marked mismatch existed between the provision and the use of resources. Surgical activities in the hospital were the major observed cause for this mismatch, mainly because ICUs were often used instead of the recovery room, which operated only about 8 to 10 hrs/day during working days. In addition to an absence of clearly written policies for the use of the facilities, a lack of sound ICU business organization and management was also documented and may have contributed to the observed misuse of resources and the dissatisfaction and burnout of hospital personnel. In order to improve the use of resources and to establish a controllable program of cost containment in ICUs in The Netherlands, the recommendations made to Dutch authorities were aggregated under two headings: a) the adoption of a quantifiable method for defining levels of ICU care; and b) the enforcement of the professional organization and management of ICUs.

The incidence of respiratory tract infections was determined in 59 multiple trauma patients requiring prolonged intensive care (greater than 5 days) and receiving no antibiotic prophylaxis. Early pneumonia (less than 48 hr) with S. aureus, S. pneumoniae, and/or H. influenzae was found in 44% of patients. Secondary colonization of the oropharynx and respiratory tract with ICU-associated Gram-negative bacilli followed by pneumonia occurred in 12 patients (20%). The overall incidence of respiratory tract infections was 59%. In a prospective open trial three prophylactic antibiotic regimens were compared: 17 patients were treated with intestinal decontamination using nonabsorbable antibiotics (polymyxin E 400 mg, tobramycin 320 mg, amphotericin B 2,000 mg/day). No difference in infection rate was found. Twenty-five patients were treated with intestinal and oropharyngeal decontamination using an ointment containing 2% of the same antibiotics. Secondary colonization and infection of the respiratory tract with Gram-negative bacilli was significantly reduced (p less than 0.001). The incidence of early (Gram-positive) infections, however, was unchanged. Another group of 63 patients was treated with systemic antibiotic prophylaxis during the first days in combination with oropharyngeal and intestinal decontamination. The incidence of early pneumonia was significantly reduced (p less than 0.001). Five patients (8%) developed an infection. Superinfections were not observed.

Ketanserin (R 41468) blocks selectively the 5HT2 receptors. We studied the effects of 10 mg of Ketanserin i.v. in 11 patients after cardiopulmonary by-pass. A sudden decrease in arterial blood pressure and in filling pressures way observed. The heart rate stayed unchanged and the rate pressure product decreased significantly. Cardiac output increased. The observed effects were essentially those of vasodilation without increases in heart rate. This pilot study showed that the 5HT2 receptors blockade may be of clinical value in the quick reversal of hemodynamic instability after cardiopulmonary by-pass.

The described modification of the Cameco URS-701 ventilator increases the frequency possibilities from zero to 40, without interfering with the ventilator pattern of each cycle and satisfies the required conditions for a classical IMV-system. Moreover it can provide longer periods of controlled ventilation alternating with periods of spontaneous respiration. This adaptation, mainly consisting of the introduction of a timer in the electrical circuit of the machine, provides us with a safe IMV system on our Engstrom 150 type ventilator and leads to a broader concept of IMV.