Feeding of wheat bran and sugar beet pulp as sole supplements in high-forage diets emphasizes the potential of dairy cattle for human food supply.

Besides the widely discussed negative environmental effects of dairy production, such as greenhouse gas emissions, the feeding of large amounts of potentially human-edible feedstuffs to dairy cows is another important sustainability concern. The aim of this study was therefore to investigate the effects of a complete substitution of common cereal grains and pulses with a mixture of wheat bran and sugar beet pulp in a high-forage diet on cow performance, production efficiency, feed intake, and ruminating behavior, as well as on net food production potential. Thirteen multiparous and 7 primiparous mid-lactation Holstein dairy cows were randomly assigned to 1 of 2 treatments in a change-over design with 7-wk periods. Cows were fed a high-forage diet (grass silage and hay accounted for 75% of the dry matter intake), supplemented with either a cereal grain-based concentrate mixture (CON), or a mixture of wheat bran and dried sugar beet pulp (WBBP). Human-edible inputs were calculated for 2 different scenarios based on minimum and maximum potential recovery rates of human-edible energy and protein from the respective feedstuffs. Dietary starch and neutral detergent fiber contents were 3.0 and 44.1% for WBBP, compared with 10.8 and 38.2% in CON, respectively. Dietary treatment did not affect milk production, milk composition, feed intake, or total chewing activity. However, chewing index expressed in minutes per kilogram of neutral detergent fiber ingested was 12% lower in WBBP compared with CON. In comparison to CON, the human-edible feed conversion efficiencies for energy and protein, defined as human-edible output per human-edible input, were 6.8 and 5.3 times higher, respectively, in WBBP under the maximum scenario. For the maximum scenario, the daily net food production (human-edible output minus human-edible input) increased from 5.4 MJ and 250 g of crude protein per cow in CON to 61.5 MJ and 630 g of crude protein in the WBBP diet. In conclusion, our data suggest that in forage-based dairy production systems, wheat bran and sugar beet pulp could replace common cereal grains in mid-lactation dairy cows without impairing performance, while strongly increasing human-edible feed conversion efficiency and net food production index.

Feeding of by-products completely replaced cereals and pulses in dairy cows and enhanced edible feed conversion ratio.

When fed human-edible feeds, such as grains and pulses, dairy cows are very inefficient in transforming them into animal products. Therefore, strategies to reduce human-edible inputs in dairy cow feeding are needed to improve food efficiency. The aim of this feeding trial was to analyze the effect of the full substitution of a common concentrate mixture with a by-product concentrate mixture on milk production, feed intake, blood values, and the edible feed conversion ratio (eFCR), defined as human-edible output per human edible input. The experiment was conducted as a change-over design, with each experimental period lasting for 7wk. Thirteen multiparous and 5 primiparous Holstein cows were randomly assigned to 1 of 2 treatments. Treatments consisted of a grass silage-based forage diet supplemented with either conventional ingredients or solely by-products from the food processing industry (BP). The BP mixture had higher contents of fiber and ether extract, whereas starch content was reduced compared with the conventional mixture. Milk yield and milk solids were not affected by treatment. The eFCR in the BP group were about 4 and 2.7 times higher for energy and protein, respectively. Blood values did not indicate negative effects on cows' metabolic health status. Results of this feeding trial suggest that by-products could replace common concentrate supplements in dairy cow feeding, resulting in an increased eFCR for energy and protein which emphasizes the unique role of dairy cows as net food producers.

Substitution of common concentrates with by-products modulated ruminal fermentation, nutrient degradation, and microbial community composition in vitro.

A rumen simulation technique was used to evaluate the effects of the complete substitution of a common concentrate mixture (CON) with a mixture consisting solely of by-products from the food industry (BP) at 2 different forage-to-concentrate ratios on ruminal fermentation profile, nutrient degradation, and abundance of rumen microbiota. The experiment was a 2×2 factorial arrangement with 2 concentrate types (CON and BP) and 2 concentrate levels (25 and 50% of diet dry matter). The experiment consisted of 2 experimental runs with 12 fermentation vessels each (n=6 per treatment). Each run lasted for 10d, with data collection on the last 5d. The BP diets had lower starch, but higher neutral detergent fiber (NDF) and fat contents compared with CON. Degradation of crude protein was decreased, but NDF and nonfiber carbohydrate degradation were higher for the BP diets. At the 50% concentrate level, organic matter degradation tended to be lower for BP and CH4 formation per unit of NDF degraded was also lower for BP. The BP mixture led to a higher concentration of propionate and a lower acetate-to-propionate ratio, whereas concentrations of butyrate and caproate decreased. Concentrate type did not affect microbial community composition, except that the abundance of bacteria of the genus Prevotella was higher for BP. Increasing the concentrate level resulted in higher degradation of organic matter and crude protein. At the higher concentrate level, total short-chain fatty acid formation increased and concentrations of isobutyrate and valerate decreased. In addition, at the 50% concentrate level, numbers of protozoa increased, whereas numbers of methanogens, anaerobic fungi, and fibrolytic bacteria decreased. No interaction was noted between the 2 dietary factors on most variables, except that at the higher concentrate level the effects of BP on CH4 and CO2 formation per unit of NDF degraded, crude protein degradation, and the abundance of Prevotella were more prominent. In conclusion, the results of this study suggest that BP in the diet can adequately substitute CON with regard to ruminal fermentation profile and microbiota, showing even favorable fermentation patterns when fed at 50% inclusion rate.

Dietary supplementation with nonconventional feeds from the Middle East: assessing the effects on physicochemical and organoleptic properties of Awassi sheep milk and yogurt.

Increased feed costs affect the livelihoods of dairy sheep farmers in the Middle East. Farmers endure high risks with large fluctuations in the price of grain used as animal feed, which is further affected by drought and declining range productivity. Using agricultural by-products and treated straw or vetch grazing for supplementing sheep diets would provide resource-poor dairy farmers with increased options to reduce feed costs, but the effects of such feeds on the quality of yogurt (the main product) need to be better understood. Two experiments were conducted to evaluate these effects. The first trial evaluated alternative diets using locally available feedstuffs, including agricultural by-products, compared with traditional diets used by dairy sheep farmers, and was conducted on-station at the International Center for Agricultural Research in Dry Areas (ICARDA, Tel Hadya, Aleppo, Syria). Milking Awassi ewes (n=56) were used to test 6 alternative diets against a traditional control diet containing barley, wheat bran, and barley straw. The 6 alternative diets contained 4 or more of the following ingredients: barley, sugar beet pulp, molasses, cotton seed cake, wheat bran, urea-treated wheat straw, and barley straw. Ewes on one of the alternative diets grazed vetch pasture, whereas ewes on the control diet and the 5 alternative diets grazed native range pasture. The milk fat content was higher in diets containing urea-treated straw. Yogurt firmness and adhesiveness were significantly lower in energy-rich diets (e.g., the control diet) and in the diets rich in soluble sugar (molasses). The effects of diet on yogurt color and on citric and succinic acid contents were significant. A yogurt produced from the milk of the group grazing on vetch was the most yellowish in color, which is appealing to Syrian consumers. The content of citric acid tended to be higher in yogurts produced from diets containing molasses. The second trial was conducted on 3 farms in northern Syria to assess an alternative diet (1 of the 6 tested in the first trial) on 15 milking ewes compared with the farmer's traditional diet (control). The alternative diet increased yogurt firmness and adhesiveness by 7 to 9% and 10 to 16%, respectively. The use of nonconventional feeds available in the region enhances yogurt quality, may reduce requirements for expensive grains, and thus, increase farmers' livelihoods by targeting expanding markets with better quality products.

Prospects for using nonconventional feeds in diets for Awassi dairy sheep in Syria.

High feed costs are major obstacles for resource-poor dairy sheep farmers in West Asia, along with large fluctuation in grain and straw prices. Farmers need low-cost diets using locally available feeds that can provide sufficient milk of good quality. Two experimental trials were conducted on Awassi milking ewes to evaluate nonconventional and balanced low-cost diets against the traditional unbalanced diet used by farmers (control) on the total yields (milk, fat, protein, and total solids) and milk composition (fat, protein, total solids, and lactose), an important indicator of milk quality. The first trial was conducted at the research station of the International Center for Agricultural Research in the Dry Areas (ICARDA, Aleppo, Syria) to test 6 low-cost balanced diets using locally available feeds and agro byproducts against the control diet. Each diet was tested on 8 ewes that were kept on pasture as a basal diet, but received different supplements, including barley, wheat bran and nonconventional feeds (urea-treated wheat straw, molasses, sugar beet pulp, and cotton seed cake). Five balanced diets enhanced the total yields of milk, fat, protein, and total solids, in 2 cases, significantly. These diets increased total milk yield by 17.7 to 50.2% and decreased supplement feeding costs by 43% compared with the control. However, milk composition remained unaffected. The second trial was conducted on 3 different farms in northern Syria to assess in each farm a low-cost balanced diet on milking ewes (n=15) in comparison to the farmer's control (n=15). The balanced diet was a modification requested by farmers of the best performing diet in the on-station trial. Confirming the first trial's research results, the balanced diet outperformed the control in total yields; for instance, it increased total milk yield by 28 to 40% and raised net income by 30%, without affecting milk composition. Both trials showed that using locally available nonconventional feedstuffs, such as molasses, integrated into balanced dairy sheep diets can decrease feed costs of resource-poor farmers, while enhancing total yields of milk and milk constituents without compromising milk quality components. This will greatly improve the profitability of dairy sheep production in dry areas.

Characterization of Awassi lamb fattening systems: a Syrian case study.

Intensive lamb fattening systems are evolving in developing Middle Eastern countries due to high demand for lambs at favorable prices; however, little is known about their characteristics and constraints. A survey was conducted in Syria involving 241 farmers to characterize the fattening production systems and main constraints, with emphasis on feeding, management, labor, and marketing. Most farmers (90%) considered the income from fattening to be from medium to high, and 57% expressed that lamb fattening along with alternative income sources compose the family's livelihood strategies. Fattening systems offer employment to family members. Market price was the main decision factor to buy and sell lambs, but this was only part of various marketing aspects. Male lambs usually bought at markets at the mean age of 4 months (mean weight of 31 kg) are sold after fattening at a 50-60 kg weight range. The average yearly fattening cycle was 2.7 batches, and the average number of lambs per batch was 232. For 65% (n = 241) of the farmers the major constraint to fattening was feeding cost, and for about a half of farmers (51%, n = 241), disease outbreaks and prices for veterinarian services constituted the second important constraint. Research on least-cost fattening diets and curbing disease problems to increase farmer's income margins is needed. It is expected that due to existing commonalities, the information emerging from this study regarding major constraints to Awassi lamb fattening systems could be useful for an across-synthesis on Awassi fattening production in the region.

Short-term mortality predictions for critically ill hospitalized adults: science and ethics.

Modern life-sustaining therapy often succeeds in postponing death but may be ineffective at restoring health. Decisions that influence the time and circumstances of an individual's death are now common and require an accurate and comprehensive characterization of likely outcome. Evaluation of alternative outcomes requires acknowledgement that most patients find some outcomes to be worse than death. Improved understanding of major predictors of patient outcome, combined with rapidly expanding technical abilities to collect and manipulate large amounts of detailed clinical data, have created a new intellectual and technical basis for estimating outcomes from intensive medical care. Such objective probability estimates, such as the system described here, can reduce uncertainty about difficult clinical decisions and can be used by physicians, patients, and society to reorient health care toward more scientifically and ethically defensible approaches.

Effects of ruminal degradability of ensiled whole crop maize varieties on feed intake and milk production of dairy cows.

The feed value of whole crop maize silage (WCMS) depends on nutrient composition, ruminal degradability and whole tract digestibility. However, as the ruminal degradation rate is involved in physical regulation of feed intake, ruminal degradability of WCMS may also affect feed intake and milk production of dairy cows. Thus, the aim of this study was to examine relationships between nutrient composition, ruminal degradability, and whole tract digestibility of WCMS and feed intake and milk production of dairy cows. Nine varieties were tested in 3 consecutive years. Nutrient composition analyses included proximate analysis and determination of cell wall constituents. Whole tract digestibility was determined in vivo using wethers and ruminal degradability was examined in situ using four rumen-fistulated steers. Feed intake and milk production were measured using nine cows per variety. Cows were fed a ration consisting of 75.0% WCMS, 8.5% hay and 16.5% soya bean meal (dry matter basis) ad libitum. Variety did not influence nutrient composition, except for the concentration of ADF (ADFom), ADL and utilisable CP (uCP). In contrast, variety had a significant effect (P < 0.05) on ruminal degradability of NDF (aNDFom) and on whole tract digestibility of organic matter (OM) and non-fibre carbohydrates. Dry matter intake (DMI) of WCMS tended to be affected by variety (0.05

An approach to including protein quality when assessing the net contribution of livestock to human food supply.

The production of protein from animal sources is often criticized because of the low efficiency of converting plant protein from feeds into protein in the animal products. However, this critique does not consider the fact that large portions of the plant-based proteins fed to animals may be human-inedible and that the quality of animal proteins is usually superior as compared with plant proteins. The aim of the present study was therefore to assess changes in protein quality in the course of the transformation of potentially human-edible plant proteins into animal products via livestock production; data from 30 Austrian dairy farms were used as a case study. A second aim was to develop an approach for combining these changes with quantitative aspects (e.g. with the human-edible feed conversion efficiency (heFCE), defined as kilogram protein in the animal product divided by kilogram potentially human-edible protein in the feeds). Protein quality of potentially human-edible inputs and outputs was assessed using the protein digestibility-corrected amino acid score and the digestible indispensable amino acid score, two methods proposed by the Food and Agriculture Organization of the United Nations to describe the nutritional value of proteins for humans. Depending on the method used, protein scores were between 1.40 and 1.87 times higher for the animal products than for the potentially human-edible plant protein input on a barn-gate level (=protein quality ratio (PQR)). Combining the PQR of 1.87 with the heFCE for the same farms resulted in heFCE×PQR of 2.15. Thus, considering both quantity and quality, the value of the proteins in the animal products for human consumption (in this case in milk and beef) is 2.15 times higher than that of proteins in the potentially human-edible plant protein inputs. The results of this study emphasize the necessity of including protein quality changes resulting from the transformation of plant proteins to animal proteins when evaluating the net contribution of livestock to the human food supply. Furthermore, these differences in protein quality might also need to be considered when choosing a functional unit for the assessment of environmental impacts of the production of different proteins.

Physiologic abnormalities and outcome from acute disease. Evidence for a predictable relationship.

Initial physiologic data from 1625 nonoperative patients with 18 acute life-threatening diseases treated in an intensive care unit suggest a uniform predictable relationship between acute changes in normal physiologic balance and a patient's risk of death. We found that incremental deviations from normal physiologic balance represent equivalent and predictable incremental risks to survival, regardless of the disease initiating the physiologic disturbance. The relative impact of these physiologic abnormalities on outcome may depend on our understanding of the disease's mechanism of action. Diseases for which there is good understanding of underlying pathophysiology and precise treatment appear to have lower death rates throughout the range of physiologic imbalance compared with those for which pathophysiologic knowledge is limited or unknown. These results document the importance of pathophysiologic understanding to improving survival from acute disease. More importantly, they suggest a predictable relationship between risk of death and physiologic abnormalities for a wide range of diseases. The existence of such a relationship could greatly expand our prognostic ability and permit improved evaluation of new therapeutic discoveries.

Outcomes of acute exacerbation of severe congestive heart failure: quality of life, resource use, and survival. SUPPORT Investigators. The Study to Understand Prognosis and Preferences for Outcomes and Risks of Treatments.

BACKGROUND: Congestive heart failure (CHF) is a common disease with high health care costs and high mortality rates. Knowledge of the health-related quality of life outcomes of CHF may guide decision making and be useful in assessing new therapies for this population. METHODS: A prospective cohort study was conducted involving 1390 adult patients hospitalized with an acute exacerbation of severe CHF (New York Heart Association class III-IV). Demographic data and health-related quality of life were determined by interview; physiologic status and cost and intensity of care were determined from hospital charts. RESULTS: The median (25th, 75th percentiles) age of patients was 68.0 (58.2, 76.9) years; 61.7% were male. Survival was 93.4% at discharge from the index hospitalization, 72.9% at 180 days, and 61.5% at 1 year. Of patients interviewed at 180 days, the median health rating on a scale of 0 to 100 (0 indicates death; 100, excellent health) was 60 (interquartile range, 50-80), and 59.7% were independent in their activities of daily living. Overall quality of life was reported to be good, very good, or excellent in 58.2% at 180 days. Patients with worse functional capacity were more likely to die. Health perceptions among the patients with available interview data improved at 60 and 180 days after acute exacerbation of severe CHF. CONCLUSIONS: Patients hospitalized for acute exacerbation of severe CHF have a generally poor 6-month survival, but survivors retain relatively good functional status and have good health perceptions. Furthermore, health perceptions improve after the acute exacerbation.

Reliability of a measure of severity of illness: acute physiology of chronic health evaluation--II.

This study examines how reliably the components of the APACHE II score (Acute Physiology Score (APS), age and chronic health) are abstracted from the medical record in terms of inter-rater reproducibility (Intraclass Correlation Coefficient [ICC], kappa). In the sample studied, assignment of the APS is highly reproducible (ICC = 0.90). Reproducibility of the age variable (ICC = 0.998) suggests that age is accurately abstracted. Chronic health data does not fare as well as the APS and age (kappa = 0.66). This study suggests that the components of the APACHE II score can be collected reliably.

Evaluation of definitions for sepsis.

OBJECTIVE: To evaluate the current definitions for sepsis and clarify and quantify the risk for intensive care unit (ICU) patients with sepsis. DESIGN: A prospective cohort analysis of 519 patients with a primary clinical diagnosis of sepsis treated in the ICUs of 40 US hospitals drawn from a nationally representative sample of 17,440 admissions. MEASUREMENTS: Patient's age, treatment location prior to ICU admission, comorbidities, origin of sepsis, daily physiologic measurements, therapeutic intensity, and subsequent hospital mortality rate. INTERVENTION: Patients were categorized into subgroups by important risk factors and into current clinical definitions of sepsis. Patients also were provided an individual risk of hospital mortality based on their individual predicted risk by using the first ICU day APACHE III score, treatment location prior to ICU admission, and etiology of sepsis. RESULTS: Patients with a designated urinary source of sepsis had a significantly lower baseline risk of death (30 percent) than patients with other causes (54 percent, p less than 0.01). Patients admitted to the ICU from the emergency department also had significantly lower mortality (37 percent) than patients admitted from hospital wards, other units within the hospital, or transferred from other hospitals (55 percent, p less than 0.01). Recognized definitions such as "sepsis syndrome" and "septic shock" identified groups of patients with significantly different mortality rates, 40 percent and 64 percent, respectively (p less than 0.01), but the range of individual patient risks within these groups were indistinguishable from the 211 patients (41 percent) that did not meet these definitions during the initial seven days of ICU treatment. Multivariate analysis using initial APACHE III score, etiology (urosepsis or other), and treatment location prior to ICU admission provided the greatest degree of discrimination (ROC = 0.82) of patients by risk of hospital death. CONCLUSIONS: Sepsis is a complex clinical entity and could be viewed as a continuum with substantial variation in initial severity and risk of hospital death. One accurate description of sepsis is the continuous measure of hospital mortality risk estimated primarily from physiologic abnormalities.

Identification of low-risk monitor admissions to medical-surgical ICUs.

A total of 5,790 intensive care unit (ICU) admissions from 13 tertiary care institutions were studied to identify patients who were at such low risk of receiving unique ICU therapies that admission might have been avoided or the length of ICU stay reduced. We used acute severity of disease on admission to the ICU along with the type of disease or surgery to risk stratify individual ICU patients. Among 1,941 patients who only received monitoring services on admission to the ICU, 1,358 (70 percent) were predicted to have less than a 10 percent risk of requiring subsequent active ICU treatment. Only 58 (4.3 percent) of these low-risk patients actually received active treatment. The identification of low-risk patients was equally accurate in estimation and validation data sets. Our methods should allow physicians and hospitals to assess their current ICU utilization and, if appropriate, guide reductions in use.

Variations in the use of do-not-resuscitate orders in ICUS. Findings from a national study.

STUDY OBJECTIVES: To describe the variation in frequency of do-not-resuscitate (DNR) orders in 42 US ICUs and to examine the relationship between published guidelines and qualitative observations about terminal care in 9 ICUs. DESIGN: Prospective inception cohort. SETTING: Forty-two ICUs in 40 US hospitals with more than 200 beds: 26 randomly selected and 14 large tertiary-care volunteers. PARTICIPANTS: A consecutive sample of 17,440 ICU admissions during 1988 to 1990. MEASUREMENTS AND RESULTS: We used age, race, comorbid conditions, disease, functional status, and acute physiology score on ICU day 1 to predict the likelihood of a DNR order for each patient. A cross-validated model was then used to predict variations in the risk of an ICU DNR order from 0 to 45% (area under receiver operating characteristic curve = 0.9). The model was then used to compare aggregate observed with predicted frequency of ICU DNR orders. Finally, we compared observations of DNR practices by a team of clinical and organizational researchers at 9 of the 42 ICUs with published guidelines and risk-adjusted DNR frequency: 1,577 admissions (9%) had DNR orders written in the ICU (range, 1.5 to 22%). The ICU site was a significant (p < 0.0001) predictor of variance in the patient level model. DNR orders were written significantly (p < 0.05) less frequently than predicted in 5 and more frequently than predicted in 3 of 42 ICUs. Nonwhite patients had significantly (p = 0.0001) fewer DNR orders after adjustment. The research team's implicit judgments following on-site analysis failed to distinguish ICUs with more or less DNR orders than predicted. Site-visited ICUs exhibited practices to emulate and practice to avoid. CONCLUSIONS: The frequency of ICU DNR orders can be predicted based on individual risk factors for groups of ICU patients. After adjusting for differences in patient characteristics, there is significant variation in the frequency of DNR orders in a national sample of ICUs. These variations may be due to unmeasured differences in patient characteristics such as treatment preferences, religious affiliation, educational level, or physician practices. We found no relationship between risk-adjusted DNR order frequency and adherence to published guidelines.

Hypoxemia in acute pulmonary embolism.

Most patients with severe, acute pulmonary embolism (PE) have arterial hypoxemia. To further define the respective roles of ventilation to perfusion (VA/Q) mismatch and intrapulmonary shunt in the mechanism of hypoxemia, we used both right heart catheterization and the six inert gas elimination technique in seven patients with severe, acute PE (mean vascular obstruction, 55 percent) and hypoxemia (mean PaO2, 67 +/- 11 mm Hg). None had previous cardiopulmonary disease, and all were studied within the first ten days of initial symptoms. Increased calculated venous admixture (mean QVA/QT 16.6 +/- 5.1 percent) was present in all patients. The relative contributions of VA/Q mismatching and shunt to this venous admixture varied, however, according to pulmonary radiographic abnormalities and the time elapsed from initial symptoms to the gas exchange study. Although all patients had some degree of VA/Q mismatch, the two patients studied early (ie, less than 48 hours following acute PE) had normal chest x-ray film findings and no significant shunt; VA/Q mismatching accounted for most of the hypoxemia. In the others a shunt (3 to 17 percent of cardiac output) was recorded along with radiographic evidence of atelectasis or infiltrates and accounted for most of the venous admixture in one. In all patients, a low mixed venous oxygen tension (27 +/- 5 mm Hg) additionally contributed to the hypoxemia. Our findings suggest that the initial hypoxemia of acute PE is caused by an altered distribution of ventilation to perfusion. Intrapulmonary shunting contributes significantly to hypoxemia only when atelectasis or another cause of lung volume loss develops.

Predicting the duration of mechanical ventilation. The importance of disease and patient characteristics.

STUDY OBJECTIVE: To analyze the determinants of an individual patient's duration of mechanical ventilation and assess interhospital variations for average durations of ventilation. DESIGN: Prospective, multicenter, inception, cohort study. SETTING: Forty-two ICUs at 40 US hospitals. PATIENTS: A total of 5,915 patients undergoing mechanical ventilation on ICU day 1 selected from the acute physiology and chronic health evaluation (APACHE) III database of 17,440 admissions. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Utilizing APACHE III data collected on the 5,915 patients, multivariate regression analysis was performed on selected patients and disease characteristics to determine which variables were significantly associated with the duration of mechanical ventilation. An equation predicting duration of ventilation was then developed using the significant predictor variables and its accuracy was evaluated. Variables significantly associated with duration of ventilation included primary reason for ICU admission, day 1 acute physiology score (APS) of APACHE III, age, prior patient location and hospital length of stay, activity limits due to respiratory disease, serum albumin, respiratory rate, and PaO2/FIo2 measurements. Using an equation derived from these variables, predicted durations of ventilation were then calculated and compared with actual observed durations for each of the 42 ICUs. Average duration of ventilation for the 42 ICUs ranged from 2.6 to 7.9 days, but 60% of this variation was accounted for by differences in patient characteristics. CONCLUSIONS: For patients admitted to the ICU and ventilated on day 1, total duration of ventilation is primarily determined by admitting diagnosis and degree of physiologic derangement as measured by APS. An equation developed using multivariate regression techniques can accurately predict average duration of ventilation for groups of ICU patients, and we believe this equation will be useful for comparing ventilator practices between ICUs, controlling for patient differences in clinical trials of new therapies or weaning techniques, and as a quality improvement mechanism.

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.

Definitions for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis. The ACCP/SCCM Consensus Conference Committee. American College of Chest Physicians/Society of Critical Care Medicine.

An American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference was held in Northbrook in August 1991 with the goal of agreeing on a set of definitions that could be applied to patients with sepsis and its sequelae. New definitions were offered for some terms, while others were discarded. Broad definitions of sepsis and the systemic inflammatory response syndrome were proposed, along with detailed physiologic parameters by which a patient may be categorized. Definitions for severe sepsis, septic shock, hypotension, and multiple organ dysfunction syndrome were also offered. The use of severity scoring methods when dealing with septic patients was recommended as an adjunctive tool to assess mortality. Appropriate methods and applications for the use and testing of new therapies were recommended. The use of these terms and techniques should assist clinicians and researchers who deal with sepsis and its sequelae.

The APACHE III prognostic system. Risk prediction of hospital mortality for critically ill hospitalized adults.

The objective of this study was to refine the APACHE (Acute Physiology, Age, Chronic Health Evaluation) methodology in order to more accurately predict hospital mortality risk for critically ill hospitalized adults. We prospectively collected data on 17,440 unselected adult medical/surgical intensive care unit (ICU) admissions at 40 US hospitals (14 volunteer tertiary-care institutions and 26 hospitals randomly chosen to represent intensive care services nationwide). We analyzed the relationship between the patient's likelihood of surviving to hospital discharge and the following predictive variables: major medical and surgical disease categories, acute physiologic abnormalities, age, preexisting functional limitations, major comorbidities, and treatment location immediately prior to ICU admission. The APACHE III prognostic system consists of two options: (1) an APACHE III score, which can provide initial risk stratification for severely ill hospitalized patients within independently defined patient groups; and (2) an APACHE III predictive equation, which uses APACHE III score and reference data on major disease categories and treatment location immediately prior to ICU admission to provide risk estimates for hospital mortality for individual ICU patients. A five-point increase in APACHE III score (range, 0 to 299) is independently associated with a statistically significant increase in the relative risk of hospital death (odds ratio, 1.10 to 1.78) within each of 78 major medical and surgical disease categories. The overall predictive accuracy of the first-day APACHE III equation was such that, within 24 h of ICU admission, 95 percent of ICU admissions could be given a risk estimate for hospital death that was within 3 percent of that actually observed (r2 = 0.41; receiver operating characteristic = 0.90). Recording changes in the APACHE III score on each subsequent day of ICU therapy provided daily updates in these risk estimates. When applied across the individual ICUs, the first-day APACHE III equation accounted for the majority of variation in observed death rates (r2 = 0.90, p less than 0.0001).