Analysis of indications for early discharge from the intensive care unit. Clinical efficacy assessment project: American College of Physicians

Intermediate Care Unit After Cardiac Surgery: Impact on Length of Stay and Outcomes

INTRODUCTION AND OBJECTIVES

Current postoperative management of adult cardiac surgery often comprises transfer from the intensive care unit (ICU) to a conventional ward. Intermediate care units (IMCU) permit hospital resource optimization. We analyzed the impact of an IMCU on length of stay (both ICU and in-hospital) and outcomes (in-hospital mortality and 30-day readmissions) after adult cardiac surgery (IMCU-CS).

METHODS

From November 2012 to April 2015, 1324 consecutive patients were admitted to a university hospital for cardiac surgery. In May 2014, an IMCU-CS was established for postoperative care. For the purposes of this study, patients were classified into 2 groups, depending on the admission period: pre-IMCU-CS (November 2012-April 2014, n=674) and post-IMCU-CS (May 2014-April 2015, n=650).

RESULTS

There were no statistically significant differences in age, sex, risk factors, comorbidities, EuroSCORE 2, left ventricular ejection fraction, or the types of surgery (valvular in 53%, coronary in 26%, valvular plus coronary in 11.5%, and aorta in 1.8%). The ICU length of stay decreased from 4.9±11 to 2.9±6 days (mean±standard deviation; P<.001); 2 [1-4] to 1 [0-3] (median [Q1-Q3]); in-hospital length of stay decreased from 13.5±15 to 12.7±11 days (mean±standard deviation; P=.01); 9 [7-13] to 9 [7-11] (median [Q1-Q3]), in pre-IMCU-CS to post-IMCU-CS, respectively. There were no statistically significant differences in in-hospital mortality (4.9% vs 3.5%; P=.28) or 30-day readmission rate (4.3% vs 4.2%; P=.89).

CONCLUSIONS

After the establishment of an IMCU-CS for postoperative cardiac surgery, there was a reduction in ICU and in-hospital mean lengths of stay with no increase in in-hospital mortality or 30-day readmissions.

Hospital mortality of adults admitted to Intensive Care Units in hospitals with and without Intermediate Care Units: a multicentre European cohort study

Introduction

The aim of the study was to assess whether adults admitted to hospitals with both Intensive Care Units (ICU) and Intermediate Care Units (IMCU) have lower in-hospital mortality than those admitted to ICUs without an IMCU.

Methods

An observational multinational cohort study performed on patients admitted to participating ICUs during a four-week period. IMCU was defined as any physically and administratively independent unit open 24 hours a day, seven days a week providing a level of care lower than an ICU but higher than a ward. Characteristics of hospitals, ICUs and patients admitted to study ICUs were recorded. The main outcome was all-cause in-hospital mortality until hospital discharge (censored at 90 days).

Results

One hundred and sixty-seven ICUs from 17 European countries enrolled 5,834 patients. Overall, 1,113 (19.1%) patients died in the ICU and 1,397 died in hospital, with a total of 1,397 (23.9%) deaths. The illness severity was higher for patients in ICUs with an IMCU (median Simplified Acute Physiology Score (SAPS) II: 37) than for patients in ICUs without an IMCU (median SAPS II: 29, P <0.001). After adjustment for patient characteristics at admission such as illness severity, and ICU and hospital characteristics, the odds ratio of mortality was 0.63 (95% CI 0.45 to 0.88, P = 0.007) in favour of the presence of IMCU. The protective effect of the IMCU was absent in patients who were admitted for basic observation, for example, after surgery (odds ratio 1.15, 95% CI 0.65 to 2.03, P = 0.630) but was strong in patients admitted to an ICU for other reasons (odds ratio 0.54, 95% CI 0.37 to 0.80, P = 0.002).

Conclusions

The presence of an IMCU in the hospital is associated with significantly reduced adjusted hospital mortality for adults admitted to the ICU. This effect is relevant for the patients requiring full intensive treatment.

Trial registration

Clinicaltrials.gov NCT01422070. Registered 19 August 2011.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0551-8) contains supplementary material, which is available to authorized users.

Introducing an integrated intermediate care unit improves ICU utilization: a prospective intervention study

Background

Improvement of appropriate bed use and access to intensive care (ICU) beds is essential in optimizing utilization of ICU capacity. The introduction of an intermediate care unit (IMC) integrated in the ICU care may improve this utilization.

Method

In a before-after prospective intervention study in a university hospital mixed ICU, the impact of introducing a six-bed mixed IMC unit supervised and staffed by ICU physicians was investigated. Changes in ICU utilization (length of stay, frequency of mechanical ventilation use), nursing workload assessed byTISS-28 score, as well as inappropriate bed use, accessibility of the ICU (number of referrals), and clinical outcome indicators (readmission and mortality rates) were measured.

Results

During 17 months, data of 1027 ICU patients were collected. ICU utilization improved significantly with an increased appropriate use of ICU beds. However, the number of referrals, readmissions to the ICU and mortality rates did not decrease after the IMC was opened.

Conclusion

The IMC contributed to a more appropriate use of ICU facilities and did result in a significant increase in mean nursing workload at the ICU.

Changes in hospital costs after introducing an intermediate care unit: a comparative observational study

INTRODUCTION

The high cost of critical care resources has resulted in strategies to reduce the costs of ruling out low-risk patients by developing intermediate care units (IMCs). The aim of this study was to compare changes in total hospital costs for intensive care patients before and after the introduction of an IMC at the University Hospital Maastricht.

METHODS

The design was a comparative longitudinal study. The setting was a university hospital with a mixed intensive care unit (ICU), an IMC, and general wards. Changes in total hospital costs were measured for patients who were admitted to the ICU before and after the introduction of the IMC. The comparison of interest was the opening of a six-bed mixed IMC.

RESULTS

The mean total hospital cost per patient increased significantly. Before the introduction of the IMC, the total hospital cost per patient was n12,961 (+/- n14,530) and afterwards it rose to n16,513 (+/- n17,718). Multiple regression analysis was used to determine to what extent patient characteristics explained these higher hospital costs using mortality, type of stay, diagnostic categories, length of ICU and ward stay, and the Therapeutic Intervention Scoring System (TISS) as predictors. More surgical patients, greater requirements of therapeutic interventions on the ICU admission day, and longer ICU stay in patients did explain the increase in hospital costs, rather than the introduction of the IMC.

CONCLUSION

After the introduction of the IMC, the higher mean total hospital costs for patients with a high TISS score and longer ICU stay explained the cost increase.

Evaluating and planning ICUs: methods and approaches to differentiate between need and demand

OBJECTIVE

In all western countries the demand for ICU-services is increasing and complaints about a lack of ICU-beds arise--independent of the actual density of ICU-services. The demand for more ICU-beds triggered a debate on whether it is possible to define an "objective" need. It was the aim of the assessment to analyze conventional as well as innovative approaches to plan and to evaluate ICU-services.

METHOD

Systematic review, multistep searches in Medline, EmBase, Cochrane, HTA-Database, websearches, informal searches through planning and HTA-networks.

INTRODUCTION

The differences between the density of intensive care in Europe and other parts of the western world is enormous. At a first superficial glance, Austria and Germany--in absolute figures--have many more ICU-beds than any other European country. In relative figures, taken into consideration that Austria and Germany have also many more acute care beds, the number of ICU-beds is among European average. It is therefore, impossible to analyze the need for ICU-beds without taking into account the national context of delivered acute hospital services. Although ICU-services take about 15-20% of the hospital budgets, there are still more questions than answers.

RESULTS

Recent planning-documents: a review of trends in recent planning shows that all planners calculate on the basis of existing style of practice within their countries; the figures change only marginally. But while planners in countries with a relatively low ICU-bed density (Great Britan, Australia, Canada) certify a certain need for an increase, planners in countries with high density (USA, Germany, Austria) state a "satisfied need" and an over-provision of ICU-services. Innovative planners apply an "appropriateness of ICU-use" approach with analysing the actual utilisation by interpreting scores (especially TISS) and by identifying "low-risk" groups and propose a more flexible organisation of ICUs and a higher proportion of (intermediate care unit) IMCU-beds. Clinical and ICU-management tools, such as admission and discharge guidelines, strategies to reduce treatment-variations, certain organisational changes (leadership, horizontal hierarchy) and costing methods gain importance for better, more efficient and co-ordinated use of ICU-resources.

CONCLUSION

In countries with a high density of ICU-services--such as Austria and Germany--not an expanding of the capacities, but a better use of the existing resources is recommended. For a fair comparison, participation in national databases, in registers as well as benchmarking and quality-assurance programs should be enforced.

Critically ill patients readmitted to intensive care units--lessons to learn?

OBJECTIVE

To evaluate risk factors in critically ill patients who were readmitted to an intensive care unit (ICU) during their hospital stay.

DESIGN

Prospective multicenter cohort study.

PATIENTS AND SETTING

A total of 15180 patients discharged from 30 medical, surgical and mixed ICUs in Austria over a 2-year period.

MEASUREMENTS AND RESULTS

The data analyzed included data on patients' clinical characteristics, Simplified Acute Physiology Score II (SAPS II), Logistic Organ Dysfunction system (LOD), Simplified Therapeutic Intervention Scoring System (TISS-28), length of ICU stay, ICU mortality and hospital mortality. Of the 15180 patients who survived the first ICU stay, 780 patients (5.1%) were readmitted. These patients had more than a fourfold risk of dying during their hospital stay (21.7 vs 5.2%, p<0.001). For mechanically ventilated patients, the time between extubation and discharge during the first ICU stay was significantly shorter for readmitted than for non-readmitted patients (median 1 vs 2 days, p<0.001). On the day of their first ICU discharge, readmitted patients were in greater need of organ support, with more patients still requiring ventilatory, cardiovascular and renal support than non-readmitted patients.

CONCLUSIONS

The results of this study provide evidence that there exists a group of patients at higher risk of readmission to the ICU. At the time of their first ICU discharge, these patients presented with residual organ dysfunctions, which were associated with an increased risk of being readmitted. Optimizing organ functions in these patients before discharge from the ICU could result in reduced readmission rates.

A multicenter description of intermediate-care patients: comparison with ICU low-risk monitor patients

STUDY OBJECTIVES

To describe the characteristics and outcomes of patients admitted to intermediate-care areas (ICAs) and to compare them with those of ICU patients who receive monitoring only on day 1 and are at a low risk (i.e., < 10%) for receiving subsequent active life-supporting therapy (i.e., low-risk monitor patients).

DESIGN

Nonrandomized, retrospective, cohort study.

SETTING

Thirteen US teaching hospitals and 19 nonteaching hospitals.

PATIENTS

A consecutive sample of 8,971 patients at 37 ICAs and 5,116 low-risk (i.e., < 10%) monitor patients at 59 ICUs in 32 US hospitals.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

We recorded demographic and clinical characteristics, resource use, and outcomes for the ICA and ICU low-risk monitor patients. Patient data and outcomes for this study were collected concurrently or retrospectively. ICA and ICU low-risk monitor patients were similar in regard to gender, race, and frequency of comorbitities, but ICA patients were significantly (p < 0.001) older, had fewer physiologic abnormalities (mean acute physiology score, 16.7 vs 19.8, respectively), and were more frequently admitted due to nonoperative diagnoses. The mean length of stay for ICA patients was significantly longer (3.9 days) than for ICU low-risk monitor patients (2.6 days; p < 0.001). The hospital mortality rate was significantly higher for ICA patients (3.1%) compared to ICU low-risk monitor patients (2.3%; p = 0.002).

CONCLUSIONS

The clinical features of ICA patients are similar, but not identical to, those of less severely ill ICU monitor patients. Comparisons of hospital death rates and lengths of stay for these patients should be adjusted for characteristics that previously have been shown to influence these outcomes.

Qualitative review of intensive care unit quality indicators

PURPOSE

The purpose of this study was to (1) conduct a systematic review of the literature to identify interventions that improve patient outcomes in the intensive care unit (ICU); (2) evaluate potential measures of quality based on the impact, feasibility, variability, and the strength of evidence to support each measure and to categorize these measures as outcome, process, access, or complication measures; and (3) select a list of candidate quality measures that can be broadly applied to improve ICU care.

METHODS

We identified and independently reviewed all studies in Medline (1965-2000) and The Cochrane Library (Issue 3, 2001) that met the following criteria: design: observational studies, experimental trials, or systematic reviews; population: critically ill adults; and intervention: process or structure measure that was associated with improved patient outcomes: morbidity, mortality, complications, errors, costs, length of stay (LOS), and patient reported outcomes. Studies were grouped into categories by the type of outcome that was improved by the intervention. Potential quality measures were evaluated for: impact on morbidity, mortality, and costs; feasibility of the measure; and variability in the measure. We evaluated the strength of evidence for each intervention used to improve outcomes and using the Delphi method, assigned an over-all recommendation for each quality measure.

RESULTS

A total of 3,014 citations were identified. Sixty-six studies that met selection criteria reported on a variety of interventions that were associated with improved patient outcomes. We identified 6 outcome measures: ICU mortality rate, ICU LOS greater than 7 days, average ICU LOS, average days on mechanical ventilation, suboptimal management of pain, and patient/family satisfaction; 6 process measures: effective assessment of pain, appropriate use of blood transfusions, prevention of ventilator-associated pneumonia, appropriate sedation, appropriate peptic ulcer disease prophylaxis, and appropriate deep venous thrombosis prophylaxis; 4 access measures: rate of delayed admissions, rate of delayed discharges, cancelled surgical cases, and emergency department by-pass hours; and 3 complication measures: rate of unplanned ICU readmission, rate of catheter-related blood stream infections, and rate of resistant infections.

CONCLUSIONS

Further work is needed to create operational definitions and to pilot test the selected measures. The value of these measures will be determined by our ability to evaluate our current performance and implement interventions designed to improve the quality of ICU care.

Who bounces back? Physiologic and other predictors of intensive care unit readmission

OBJECTIVE

To determine the influence of changes in acute physiology scores (APS) and other patient characteristics on predicting intensive care unit (ICU) readmission.

DESIGN

Secondary analysis of a prospective cohort study.

SETTING

Single large university medical intensive care unit.

PATIENTS

A total of 4,684 consecutive admissions from January 1, 1994, to April 1, 1998, to the medical ICU.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The independent influence of patient characteristics, including daily APS, admission diagnosis, treatment status, and admission location, on ICU readmission was evaluated using logistic regression. After accounting for first ICU admission deaths, 3,310 patients were "at-risk" for ICU readmission and 317 were readmitted (9.6%). Hospital mortality was five times higher (43% vs. 8%; p < .0001), and length of stay was two times longer (16 +/- 16 vs. 32 +/- 28 days; p < .001) in readmitted patients. Mean discharge APS was significantly higher in the readmitted group compared with the not readmitted group (43 +/- 19 vs. 34 +/- 18; p > .01). Significant independent predictors of ICU readmission included discharge APS >40 (odds ratio [OR] 2.1; 95% confidence interval [CI] 1.6-2.7; p < .0001), admission to the ICU from a general medicine ward (Floor) (OR 1.9; 95% CI 1.4-2.6; p < .0001), and transfer to the ICU from other hospital (Transfer) (OR 1.7; 95% CI 1.3-2.3; p < .01). The overall model calibration and discrimination were (H-L chi2 = 3.8, df = 8; p = .85) and (receiver operating characteristic 0.67), respectively.

CONCLUSIONS

Patients readmitted to medical ICUs have significantly higher hospital lengths of stay and mortality. ICU readmissions may be more common among patients who respond poorly to treatment as measured by increased severity of illness at first ICU discharge and failure of prior therapy at another hospital or on a general medicine unit. Tertiary care ICUs may have higher than expected readmission rates and mortalities, even when accounting for severity of illness, if they care for significant numbers of transferred patients.

Intensive care unit length of stay: recent changes and future challenges

OBJECTIVE

To compare case-mix adjusted intensive care unit (ICU) length of stay for critically ill patients with a variety of medical and surgical diagnoses during a 5-yr interval.

DESIGN

Nonrandomized cohort study.

SETTING

A total of 42 ICUs at 40 US hospitals during 1988-1990 and 285 ICUs at 161 US hospitals during 1993-1996.

PATIENTS

A total of 17,105 consecutive ICU admissions during 1988-1990 and 38,888 consecutive ICU admissions during 1993-1996.

MEASUREMENTS AND MAIN RESULTS

We used patient demographic and clinical characteristics to compare observed and predicted ICU length of stay and hospital mortality. Outcomes for patients studied during 1993-1996 were predicted using multivariable models that were developed and cross-validated using the 1988-1990 database. The mean observed hospital length of stay decreased by 3 days (from 14.8 days during 1988-1990 to 11.8 days during 1993-1996), but the mean observed ICU length of stay remained similar (4.70 vs. 4.53 days). After adjusting for patient and institutional differences, the mean predicted 1993-1996 ICU stay was 4.64 days. Thus, the mean-adjusted ICU stay decreased by 0.11 days during this 5-yr interval (T-statistic, 4.35; p < .001). The adjusted mean ICU length of stay was not changed for patients with 49 (75%) of the 65 ICU admission diagnoses. In contrast, the mean observed hospital length of stay was significantly shorter for 47 (72%) of the 65 admission diagnoses, and no ICU admission diagnosis was associated with a longer hospital stay. Aggregate risk-adjusted hospital mortality during 1993-1996 (12.35%) was not significantly different during 1988-1990 (12.27%, p = .54).

CONCLUSIONS

For patients admitted to ICUs, the pressures associated with a decrease in hospital length of stay do not seem to have influenced the duration of ICU stay. Because of the high cost of intensive care, reduction in ICU stay may become a target for future cost-cutting efforts.

Patients readmitted to ICUs* : a systematic review of risk factors and outcomes

STUDY OBJECTIVE

To evaluate the causes, risk factors, and mortality rates associated with unexpected readmission to medical and surgical ICUs.

DATA SOURCES

MEDLINE citation review of primary articles focusing on ICU readmission or ICU outcomes from January 1966 to June 1999, and contact with authors of primary studies.

STUDY SELECTION

Eight primary studies of ICU readmission and eight multi-institutional ICU outcome studies that reported ICU readmission rates were included.

DATA EXTRACTION

We abstracted data on the methodology and design of the primary studies, overall rates, causes, predictors, outcomes, and measures of quality of care associated with ICU readmission.

DATA SYNTHESIS

The average ICU readmission rate of 7% (range, 4 to 14%) has remained relatively unchanged in both North America and Europe. Respiratory and cardiac conditions were the most common (30 to 70%) precipitating cause of ICU readmission. Patients readmitted to ICUs had average hospital stays at least twice as long as nonreadmitted patients. Hospital death rates were 2- to 10-times higher for readmitted patients than for those who survived an ICU admission and were never readmitted. Predictors of ICU readmission have been neither well studied nor reproducible. Unstable vital signs, especially respiratory and heart rate abnormalities, and the presence of poor pulmonary function at time of ICU discharge appear to be the most consistent predictors of ICU readmission. There were no consistent data supporting the use of readmission rates as a measure of quality of care.

CONCLUSIONS

ICU readmission is associated with dramatically higher hospital mortality. Unstable vital signs at the time of ICU discharge are the most consistent predictor of ICU readmission. Further studies focusing on processes of ICU and hospital care are needed to determine if ICU readmission rates are a measure of quality of care.

Patients readmitted to the intensive care unit during the same hospitalization: clinical features and outcomes

OBJECTIVE

To determine the clinical features and outcomes of patients readmitted to the intensive care unit (ICU) during the same hospital stay and the causes for these readmissions.

DESIGN

Multicenter, cohort study.

SETTING

Three ICUs from two teaching hospitals and four ICUs from four community hospitals.

PATIENTS

All ICU admissions were collected prospectively for a registry database in the seven ICUs. We retrospectively analyzed ICU admissions between January 1, 1995 and February 29, 1996.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

During the study period, 236 (4.6%) of the patients discharged alive from the ICU were readmitted to the unit. Patients with gastrointestinal (GI) and neurologic diagnoses had the highest readmission rate. Of the readmissions, 45% had recurrence of the initial disease, 39% experienced new complications, and 14% required further planned operation. Among patients readmitted for the same illness, cardiovascular and respiratory problems were the most frequent diagnoses. Of patients readmitted with a new diagnosis, 30% initially had GI diseases, while respiratory diseases accounted for 58% of the new complications. Readmissions within 24 hrs occurred in 27% of all readmissions. Patients requiring readmission had a higher hospital mortality rate (31.4%) compared with those not requiring readmission (4.3%, p < .001), even after adjustment for disease severity score (odds ratio = 5.93, p < .001).

CONCLUSIONS

Patients with GI and neurologic diseases are at greatest risk of requiring ICU readmission. Respiratory diseases are the major reason for readmission due to new complications. Readmitted patients have a high risk of hospital death that may be underestimated by the usual physiologic indicators on either initial admission or readmission. Further studies are required to determine if patients at risk for readmission can be identified early to improve the outcome.

Simplified acute physiology score II for measuring severity of illness in intermediate care units

OBJECTIVES

To assess the efficacy of the Simplified Acute Physiology Score (SAPS II) in intermediate care units. A number of patients hospitalized in the intensive care unit (ICU) could be hospitalized in alternative structures, intermediate care units, which are equipped to handle their monitoring needs and able to provide adequate treatment at a lower cost. Characterization of the patients relies on the assessment of their severity of illness by severity scores. The efficiency of severity scores has been established in ICU patients, but not in the setting of intermediate care units.

DESIGN

Prospective study.

SETTING

Intermediate care unit of a multidisciplinary hospital.

PATIENTS

Four hundred thirty-three patients admitted to the intermediate care unit.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 561 consecutive patients admitted to the intermediate care unit during a 12-mo period, 433 patients could be included in the analysis. Patients were admitted from the emergency ward (60.9%). Of the study patients, 60.9% were admitted from the emergency ward for mostly (96%) medical reasons. Average length of stay was 3.1 +/- 2.3 (SD) days. Death rate in the intermediate care unit was 2.7% (n = 11). Average SAPS II was 22.3 +/- 12.0 (range 6 to 73). Hospital death rate was 8.1%, whereas the expected mortality rate derived from SAPS II was 8.7%. To assess the performance of the system, a formal goodness-of-fit test was performed to evaluate calibration. Calibration was accurate using the C coefficient of Hosmer-Lemeshow statistics (C = 2.4; p> 0.5). The discriminant power of SAPS II, measured by the area under the receiver operating characteristic curve was excellent (0.85 +/- 0.04).

CONCLUSIONS

The SAPS II assessment of severity of illness in patients admitted to an intermediate care unit is reliable. These results will need to be confirmed, using different patient samplings from intermediate care units.

Assessment of the prognosis of coronary patients: performance and customization of generic severity indexes

STUDY OBJECTIVE

To assess the prognostic performance of general severity systems (APACHE II [acute physiology and chronic health evaluation], simplified acute physiology score [SAPS II], and mortality probability models [MPM II]) in coronary patients and to derive new customized indexes for coronary patients using a reduced number of variables.

DESIGN

Inception cohort.

SETTING

Adult medical and surgical ICUs in 17 hospitals in Catalonia and the Balearic Islands.

PATIENTS

Four hundred fifty-six patients with acute myocardial infarction.

MEASUREMENTS AND RESULTS

The APACHE II, SAPS II, and MPM II variables and survival status at hospital discharge have been collected. Performance of the severity systems was assessed by evaluating calibration and discrimination. Logistic regression was used to customize the MPM II(24) and SAPS II indexes. Discrimination was high enough for all of the models. However, calibration of the MPM II(24) was not as satisfactory as for the other models. The MPM II(24) and SAPS II were both reduced to five variables (MPM II(24 cor:) age, PaO2, continuous vasoactive drugs, urinary output, and mechanical ventilation; SAPS II(cor:) age, PaO2/FI(O2) ratio, systolic BP, Glasgow coma score, and urinary output). Both models showed better calibration and discrimination than the original ones.

CONCLUSIONS

Prognostic indexes developed for multidisciplinary patients show good performance when applied to patients with acute myocardial infarction, but customization can reduce the number of variables necessary to compute them without a loss of, and a possible improvement in, prognostic accuracy.

Planning patient services for intermediate care units: insights based on care for intensive care unit low-risk monitor admissions

OBJECTIVE

To 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.

DESIGN

Prospective, multicenter, inception cohort analysis.

SETTING

Forty U.S. hospitals with > 200 beds, including 26 hospitals that were randomly selected and 14 that volunteered for the study.

PATIENTS

A sample of 8,040 ICU patients admitted to the ICU for monitoring, who received no active life-support treatment on ICU day 1.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographic, 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.

CONCLUSIONS

The 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.

Evaluation of trauma care: validation of the TRISS method in an Italian ICU

OBJECTIVE

To validate the TRISS method as an audit system on a group of patients with severe trauma admitted to an Italian general intensive care unit (ICU).

DESIGN

Prospective, cohort study of consecutive admissions to the ICU.

SETTING

A 6-bed general ICU in a 500-bed general hospital.

PATIENTS

190 patients with severe trauma admitted from January 1992 to December 1993 were considered eligible. Patients lacking the data necessary to calculate the TRISS probability of survival, or for whom the ultimate outcome was unknown, were excluded. 162 patients were included in the study.

INTERVENTIONS

None.

OUTCOME MEASURE

Vital status at discharge from the last hospital that admitted the patient for the trauma being considered.

RESULTS

The Hosmer-Lemeshow goodness-of-fit tests were: H = 16.9, df = 10, p = 0.076; C = 5.8, df = 10, p = 0.831; H 3.5, df = 3, p = 0.31. The area under the receiver operating characteristic curve was 0.963 (SE +/- 0.019). Classification measures at a decision criterion of 0.5 were: sensitivity 0.857, specificity 0.964, positive predictive value 0.782, negative predictive value 0.978, total correct classification 0.950, and the Youden index 0.821. The positive likelihood ratio (LHR) was 24.17, whereas the negative LHR was 0.14.

CONCLUSIONS

The results of the validation of the TRISS method showed adequate calibration and high discriminatory power in Italian ICU trauma patients also, allowing confidence in the use of this method as an audit tool in our ICU. Some caution is advisable in extending these results to patients with operable intracranial injuries, due to the relatively low number of such cases included in the study.

The use of risk predictions to identify candidates for intermediate care units. Implications for intensive care utilization and cost

OBJECTIVE

To develop a predictive equation that estimates the probability of life-supporting therapy among ICU monitor admissions and to explore its potential for reducing cost and improving ICU utilization.

DESIGN

Prospective inception cohort analysis.

PARTICIPANTS

Forty-two ICUs in 40 US hospitals with more than 200 beds and a consecutive sample of 17,440 ICU admissions.

INTERVENTIONS

A multivariate equation was developed to estimate the probability of life support for ICU monitoring admissions during an entire ICU stay.

MEASUREMENTS

Demographic, physiologic, and treatment information obtained during the first 24 h in the ICU and over the first 7 ICU days.

RESULTS

The most important determinants of subsequent risk for life-supporting (active) treatment were diagnosis, the acute physiology score of APACHE III, age, operative status, and the patient's location and hospital length of stay before ICU admission. Among 8,040 ICU monitoring admissions, 6,180 (76.8%) had a low (< 10%) risk for receiving active treatment during the ICU stay; 95.6% received no subsequent active treatment. Review of outcomes and the type and amount of therapy received suggest that most low-risk ICU monitor admissions could be safely cared for in an intermediate care setting.

CONCLUSION

Objective predictions can accurately identify groups of ICU admissions who are at a low risk for receiving life support. This capability can be used to assess ICU resource use and develop strategies for providing graded critical care services at a reduced cost.

High dependency units in the UK: variable size, variable character, few in number

An exploratory descriptive survey was conducted to determine the size and character of high dependency units (HDUs) in the UK. A telephone survey and subsequent postal questionnaire was sent to the 39 general HDUs in the UK determined by a recent survey from the Royal College of Anaesthetists; replies were received from 28. Most HDUs (82%, n = 23) were geographically distinct from the intensive care unit and varied in size from three to 13 beds, although only 64% (n = 18) reported that all beds were currently open. Nurse: patient ratios were at least 1:3. Fifty per cent of units had one or more designated consultants in charge, although only 11% (n = 3) had specifically designated consultant sessions. Junior medical cover was provided mainly by the on-call speciality term. Twenty units acted as a step-down facility for discharged intensive care unit patients and 21 offered a step-up facility for patients from general wards. Provision of facilities and levels of monitoring varied between these units. Few HDUs exist in the UK and they are variable in size and in the facilities and monitoring procedures which they provide. Future studies are urgently required to determine cost-effectiveness and outcome benefit of this intermediate care facility.