Xiaolu Sun

A comparison of risks and outcomes for patients with organ system failure : 1982-1990

OBJECTIVES To 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. DESIGN Prospective, multicenter, inception cohort analysis. SETTING Sixty intensive care units (ICUs) at 53 U.S. hospitals. PATIENTS A total of 17,440 ICU admissions treated in 1988 to 1990 and 5,677 ICU admissions treated in 1979 to 1982. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS At 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 = 7 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 patients 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). CONCLUSIONS Organ 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.

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.

Evaluating laboratory usage in the intensive care unit: patient and institutional characteristics that influence frequency of blood sampling.

OBJECTIVES To develop a predictive equation to estimate the frequency of blood drawing for intensive care unit (ICU) laboratory tests and to evaluate variations in ICU blood sampling practices after adjusting for patient and institutional factors. DESIGN Prospective, inception, cohort study. SETTING Forty-two ICUs in 40 hospitals, including 20 teaching and 17 nonteaching ICUs. PATIENTS A consecutive sample of 17,440 ICU admissions, in which 14,043 blood samples were drawn for laboratory testing on ICU days 2 to 7. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Patient demographic, physiologic, and treatment data were obtained on ICU day 1; the type and number of blood samples for laboratory testing were recorded on ICU days 1 to 7. In the 42 ICUs, a mean of 16.2 blood samples were drawn for tests on ICU days 2 to 7, but varied between 23 samples in the teaching ICUs and 9.9 samples in nonteaching ICUs. Using only ICU day 1 patient data, we predicted the subsequent number of samples drawn on ICU day 2 (R2 = .26 across individual patients) and on ICU days 2 to 7 (R2 = .26 across individual patients). The most important determinants of the number of blood samples drawn on ICU days 2 to 7 were the ICU day 1 Acute Physiology Score and admission diagnosis. After controlling for patient variables, hospital teaching status, number of beds, and location in the East and South were significantly (p < .05) associated with increased blood sampling on ICU day 2 and on ICU days 2 to 7. More frequent use of an arterial cannula and mechanical ventilation were also associated with increased blood sampling on subsequent days. CONCLUSIONS The ability to adjust for patient and institutional variables and to predict the number of blood samples drawn for laboratory tests can allow ICUs to compare their practices with those of other units. When integrated into a continuous quality improvement process, this information can be used to identify and focus on opportunities for improving blood conservation and reducing excessive diagnostic testing.

Does selective decontamination of the digestive tract reduce mortality for severely ill patients

OBJECTIVE To investigate the relationship between baseline risk of death and reduced mortality after selective decontamination of the digestive tract in intensive care unit patients. DESIGN Analysis of data from a meta-analysis of 23 randomized, controlled trials. PATIENTS A total of 4,142 adult intensive care unit patients from the 23 trials. MEASUREMENTS AND MAIN RESULTS Mortality for patients receiving selective decontamination of the digestive tract treatment was analyzed as a function of baseline risk of death at study entry, using weighted least squares regression across all 23 trials. In testing whether the slope of the regression is different than 1.0, the observed t value is 3.32 (p < .004), suggesting that the efficacy of selective decontamination of the digestive tract in reducing mortality is significantly better in populations at high mortality risk at study entry. CONCLUSIONS Mortality reduction from selective decontamination of the digestive tract appears related to the mortality risk of patients at the time of study entry. Future trials should consider using baseline risk assessment as part of trial design and outcome analysis.

Risk assessment in recent clinical trials in sepsis/SIRS: lessons learned and future directions

This presentation reviews recent evidence that the design and analysis of clinical trials in sepsis could be improved by using individualized sepsis specific risk assessments. These individual patient risk profiles are derived from independent databases. They describe patients on a continuum of risk. They have correlated very closely to mortality outcomes in recent clinical trials. These individual risk assessments can improve the interpretation of trial data by controlling for potentially confounding patient risk factors, thereby permitting the signal or impact from novel therapy to be more precisely determined. When these individual risk assessments are combined with data on the degree of the hosts specific inflammatory response they may eventually lead to the development of specific patient profiles to describe where immunotherapy is appropriate and other situations where it may either not be indicated or pose a risk. This relationship needs further investigation, however, before it can be confirmed. Changes in the acute physiology score can also hold substantial promise as an alternative endpoint for clinical trials. Therapies which significantly and consistently reduce the APS during the initial days of sepsis in small, early exploratory Phase I and II trials may be excellent candidates for investigation in larger Phase III studies.