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Results for “physiologic variables”

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PubMed2002

Tracking of physical and physiological risk variables among ethnic subgroups from third to eighth grade: the Child and Adolescent Trial for Cardiovascular Health cohort study.

BACKGROUND: The Child and Adolescent Trial for Cardiovascular Health (CATCH), a multisite field trial, tested the effectiveness of multiple interventions for cardiovascular disease risk behaviors in children in third through fifth grades. This paper reports the tracking of physiologic variables through eighth grade. METHODS: The cohort began with 5,106 third grade students from diverse ethnic backgrounds: 69% Caucasian, 14% Hispanic, 13% African American, and 4% other. Seventy-two percent of students were remeasured. Measures described are serum lipids, blood pressure, and body anthropometrics. Tracking was examined across three time points (third, fifth, and eighth grades) with a scaled Kendall concordance coefficient and percentage retention within quintiles across time. RESULTS: For the overall sample, tacking was strongest for body mass index (BMI) (Kendall coefficient = 0.86) and weight (0.86), followed by skinfold thicknesses (0.72-0.78), serum lipids (0.67-0.72), and blood pressure (0.45-0.51). For BMI, 96% of students stayed within +/-1 quintile from third to fifth grades; 90% stayed within this range from third to eighth grades. CONCLUSIONS: There were small but noticeable gender and ethnic differences: tracking was stronger among boys and African American students. These results demonstrate that the children's relative level of cardiovascular risk remained stable over a 6-year period.

Adolescent↗

PubMedDate not supplied

Effects of physiologic waveform variability in triggered MR imaging: theoretical analysis.

One of the assumptions inherent in most forms of triggered magnetic resonance (MR) imaging is that the pulsatile waveform (be it cardiac, respiratory, or some other) is purely periodic. In reality, the periodicity condition is rarely met. Physiologic waveform variability may lead to image artifacts and errors in velocity or volume flow rate estimates. The authors analyze the effects of physiologic waveform variability in triggered MR imaging. They propose that this variability be treated as a modulation of the underlying motion waveform. This report concentrates on amplitude modulation of the velocity waveform, which results in amplitude and phase modulation of the transverse magnetization. Established Fourier and modulation theory and the recently described principles of (k,t)-space were used to derive the appearance of physiologic waveform variability artifacts in triggered MR images and to predict errors in time-averaged and instantaneous velocity estimates that may result from such motion effects, including effects such as ghost overlap. Simulations and experimental results are provided to confirm the theory.

Algorithms↗

PubMedDate not supplied

Predicting fatigue and depression in HIV-positive gay men.

HIV-related fatigue is a prevalent and troubling symptom for HIV-positive people. The purpose of the study was to develop a model for predicting fatigue and depression among HIV-positive gay men as a function of history of fatigue and depression in the previous year and to determine whether psychological and psychosocial variables or physiologic variables better predict fatigue. Data from 96 HIV-positive gay men followed longitudinally for up to 7.5 years were used to develop logistic regression models for predicting fatigue and depression. Fatigue was predicted by both physiologic and psychological risk factors, whereas depression was predicted by only psychological risk factors.

Adult↗

PubMed2003

Individual differences in diffuse noxious inhibitory controls (DNIC): association with clinical variables.

Laboratory pain research has been criticized as being irrelevant to the clinical experience of pain. Previous findings have been inconsistent with some studies suggesting that experimental pain responses may be related to the reported presence or severity of chronic pain, while others report no such associations. However, few of these studies assess a variety of laboratory pain responses, and none has assessed relationships between clinical pain and diffuse noxious inhibitory controls (DNIC) in healthy subjects. We administered questionnaire measures of pain, quality of life, and psychological variables to a sample of healthy adults participating in a laboratory study of age differences in pain responses. DNIC was not related to other laboratory pain responses, psychological variables, or physiological variables measured in the present study. Regression models predicting health-related quality of life (e.g. pain, physical functioning) revealed that age, sex, and DNIC responses explained between 10 and 25% of the variance in these dependent measures. Of the laboratory pain variables, only DNIC was the sole consistent predictor of clinical pain and physical health, with greater DNIC responses related to less pain, better physical functioning, and better self-rated health. In addition, age differences in DNIC appeared to partially mediate age differences in physical functioning. These findings highlight the potential clinical relevance of experimental pain procedures and suggest that DNIC may be the laboratory pain response most closely associated with clinical pain and health-related variables.

Adult↗

PubMed2001

Physiologic instability in panic disorder and generalized anxiety disorder.

BACKGROUND: Because panic attacks can be accompanied by surges in physiologic activation, we tested the hypothesis that panic disorder is characterized by fluctuations of physiologic variables in the absence of external triggers. METHODS: Sixteen patients with panic disorder, 15 with generalized anxiety disorder, and 19 normal control subjects were asked to sit quietly for 30 min. Electrodermal, cardiovascular, and respiratory measures were analyzed using complex demodulation to quantify variability in physiologic indices. RESULTS: Both patient groups reported equally more anxiety and cardiac symptoms than control subjects, but certain other somatic symptoms, including breathlessness, were elevated only in panic disorder patients. Mean end-tidal pCO(2) and respiratory rates were lower, and tidal volume and the number of sighs were higher in panic disorder patients than control subjects. Neither cardiovascular (heart rate, arterial pressure, cardiac output), nor electrodermal instability including sighs distinguished the groups; however, tidal volume instability was greater in panic disorder than generalized anxiety disorder patients or control subjects. Several other respiratory measures (pCO(2), respiratory rate, minute volume, duty cycle) showed greater instability in both patient groups than in control subjects. CONCLUSIONS: Respiration is particularly unstable in panic disorder, underlining the importance of respiratory physiology in understanding this disorder. Whether our findings represent state or trait characteristics is discussed.

Adult↗

PubMed2004

Human models of endotoxemia and recombinant human activated protein C.

OBJECTIVES: To review human models of endotoxemia with an emphasis on the inflammatory and coagulopathic effects of lipopolysaccharide to describe the possible mechanisms of clinical benefit of recombinant human activated protein C (drotrecogin alfa [activated]) in severe sepsis. DATA SOURCE: A selected review of published literature in English on human endotoxemia models with special attention to studies using drotrecogin alfa (activated) in concert with endotoxemia. DATA EXTRACTION AND SYNTHESIS: After intravenous administration of purified lipopolysaccharide, subjects report constitutional influenza-like symptoms associated with an increase in temperature. Within 1 hr of lipopolysaccharide infusion, total leukocyte counts decline. Sustained leukocytosis, due to an increase in neutrophils counts, follows. An increase in markers of neutrophil activation (e.g., serum elastase) accompanies this leukocytosis. Production of tumor necrosis factor-alpha, interleukin-6, and interleukin-8 is also increased. In association with an inflammatory response, lipopolysaccharide administration also activates the coagulation system. Lipopolysaccharide infusion generates thrombin and initially activates fibrinolysis but subsequently generates inhibitors of the fibrinolytic system. Serum levels of endogenous inhibitors of coagulation (e.g., antithrombin, protein C, tissue factor pathway inhibitor) are not affected. Data are available for 40 subjects who have participated in placebo-controlled studies of drotrecogin alfa (activated) infusion before an intravenous dose of lipopolysaccharide. In these subjects, drotrecogin alfa (activated) has minimal effects on measured variables, including physiologic variables, markers of inflammation, and measures of sepsis-induced coagulopathy. CONCLUSION: Human endotoxemia is, at best, an incomplete model of human sepsis. In two studies using recombinant human activated protein C in the setting of human endotoxemia, there were minimal effects on hemodynamics, inflammation, thrombin generation, fibrinolysis, and markers of cellular activation. Other putative mechanisms of recombinant human activated protein C, such as inhibition of apoptosis and leukocyte recruitment, remain to be studied.

Anti-Infective Agents↗

PubMed2001

Intercenter variance in clinical trials of head trauma--experience of the National Acute Brain Injury Study: Hypothermia.

OBJECT: In a recently conducted trial of hypothermia in patients with severe brain injury, differences were found in the effects of hypothermia treatment among various centers. This analysis explores the reasons for such differences. METHODS: The authors reviewed data obtained in 392 patients treated for severe brain injury. Prerandomization variables, critical physiological variables, treatment variables, and accrual methodologies were investigated among various centers. Hypothermia was found to be detrimental in patients older than the age of 45 years, beneficial in patients younger than 45 years of age in whom hypothermia was present on admission, and without effect in those in whom normothermia was documented on admission. Marginally significant differences (p < 0.054) in the intercenter outcomes of hypothermia-treated patients were likely the result of wide differences in the percentage of patients older than 45 years of age and in the percentage of patients in whom hypothermia was present on admission among centers. The trial sensitivity was likely diminished by significant differences in the incidence of mean arterial blood pressure (MABP) less than 70 mm Hg (p < 0.001) and cerebral perfusion pressure (CPP) less than 50 mm Hg (p < 0.05) but not intracranial pressure (ICP) greater than 25 mm Hg (not significant) among patients in the various centers. Hours of vasopressor usage (p < 0.03) and morphine dose (p < 0.001) and the percentage of dehydrated patients varied significantly among centers (p < 0.001). The participation of small centers increased intercenter variance and diminished the quality of data. CONCLUSIONS: For Phase III clinical trials we recommend: 1) a detailed protocol specifying fluid and MABP, ICP, and CPP management: 2) continuous monitoring of protocol compliance; 3) a run-in period for new centers to test accrual and protocol adherence; and 4) inclusion of only centers in which patients are regularly randomized.

Adult↗

PubMed2003

[Factors influencing health care needs of solitude elderly].

PURPOSE: This study was to identify factors that influence the health care needs of that over 65 years of age in Mokpo, Korea. METHOD: The data was collected from June 2002 to September 2002. The subjects were 120 homebound solitude elderly(age=76.8). Subjects were interviewed with structured questionnaire in order to identify the health care needs, health variables (perceived health status, risk of malnutrition, K-IADL), psychological variables(self-esteem, depression) and demographic variables. physiological health variables (height, weight, blood pressure, pulse, blood sugar)were assessed after the interview. RESULT: In general perceived health status was poor, risk of malnutrition was high, number of disease was 3 disease, self-esteem was low but depression was high and health care needs were relatively high. Among the elderly education & counseling needs topped the list. In regression analysis, health care needs were significantly influenced by IADL(23%), duration of solitudes(4%), sex(3%), and education(1%). These variables explained 31% of the variances in health care needs. CONCLUSION: The result identified that health care needs should be a considered in IADL, female, duration of solitudes and education for the solitude elderly.

English Abstract↗

PubMed1999

[Peripheral muscle strength in stable COPD patients: correlation with respiratory function variables and quality of life].

The aim of this study was to assess peripheral muscle strength in patients with chronic obstructive pulmonary disease (COPD) using a simple test and to look for correlation with function variables, physiological strength variables and quality of life parameters. Twenty-three COPD patients with moderate to severe air-flow limitation (FEV1 = 39 +/- 12%) in stable phase but displaying inability to carry out daily tasks were enrolled. Peripheral muscle strength was assessed in all patients by measuring the maximum load in a single repetition of five simple upper and lower extremity exercises performed at a multi-gymnastics station. Results were compared to respiratory function variables (FVC, FEV1, FEV1/FVC and gasometry), to results of an exercise test on a cycle ergometer with monitoring of respiratory gases (VEmax, VO2max and Wmax), to endurance (minutes) to dyspnea (Mahler's scale) and to quality of life (Chronic Respiratory Disease Questionnaire-CRDQ). No relation between functional parameters and endurance in minutes was found. Minute ventilation (VE) proved to be significantly related to oxygen intake (VO) and maximum work in the stress test. Dyspnea on Mahler's scale was unrelated, but fatigue variables and emotional function variables on the CRDQ were related. We conclude that peripheral muscle strength is unrelated to level of flow limitation or exercise tolerance in COPD patients. Peripheral muscle strength is related, however, to maximum work load and some aspects of quality of life.

Aged↗

PubMed1996

Frequency of variable measurement in 16 pediatric intensive care units: influence on accuracy and potential for bias in severity of illness assessment.

OBJECTIVES: We evaluated: a) whether the frequency of variable measurement could influence the performance of the Pediatric Risk of Mortality (PRISM) score; b) whether measurement frequency of physiologic variables varied between individual pediatric intensive care units (ICUs), and c) if so, how much of this variability could be attributed to institution-level and patient-level factors. DESIGN: Prospective cohort. SETTING: Sixteen pediatric ICUs, chosen for their diversity. PATIENTS: Consecutive admissions (n = 5,415). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: First, the measurement frequency of the 14 physiologic variables in the PRISM score was included in the logistic regression model predicting mortality risk. Measurement frequency was not significant, alone or in its interaction with the PRISM score. Second, the presence or absence of measurement of each physiologic variable was included in the logistic model using indicator variables; none was significant. Finally, the contribution of the individual pediatric ICUs and patient factors in explaining the variability in the frequency of physiologic variable measurement were investigated with linear regression analysis. In this analysis, the separation of severity of illness from measurement frequency was accomplished by computing the PRISM score from the first 4 hrs and measurement frequencies from hours 5 through 24. Overall, 70.22% (r2) of the variability of measurement frequency could be explained by the factors included in the linear regression model. The individual ICUs accounted for a total of only 6.23% of the explained variability and no individual hospital accounted for > 1.44% of the variability. Other variables positively correlated with measurement frequency included the presence or absence of a pediatric intensivist, and whether the institution was a children's hospital or not. Variables negatively correlated with measurement frequency included larger ICUs and house officers assigned to the ICU. CONCLUSIONS: Although measurement frequency is associated with unit-level factors, their contribution to the overall variability is small and unlikely to influence the accuracy or reliability of the PRISM score. It is unlikely that there are routine biases associated with differences in measurement frequency of PRISM variables within the spectrum of care practices that now exist.

Child↗

PubMed1998

Inertia and Resilience in the Responses of the Aquatic Bryophyte Fontinalis antipyretica Hedw. to Thermal Stress

The physiological responses of the aquatic bryophyte Fontinalis antipyretica Hedw. to high temperatures, ranging from 16 degreesC (control) to 34 degreesC, were investigated experimentally. Plant samples were maintained at the temperature under study for up to 25 days with regular determination of physiological variables (pigment ratio and photosynthetic and respiratory rates). Physiological responses to temperature did not differ significantly between mosses collected from a normal river site and from a river site with abnormally high temperature due to input from a hot spring. Simple curve-fitting procedures and summary statistics analogous to those used in toxicological research were employed to compare responses as revealed by the different physiological variables. In a second series of experiments, the capacity of F. antipyretica to recover from high-temperature stress was investigated by maintaining samples at 30 degreesC for 2, 4, or 10 days, then transferring the samples to normal conditions (16 degreesC) for 40 days. Physiological variables were again monitored at regular intervals throughout both phases of the experiment. In general, good recovery was observed even after exposure to high temperatures for 10 days. The results of these assays allow quantification of the relationship between a pigment ratio and net photosynthesis rate.

Journal Article↗

PubMed1996

PRISM III: an updated Pediatric Risk of Mortality score.

OBJECTIVES: The relationship between physiologic status and mortality risk should be reevaluated as new treatment protocols, therapeutic interventions, and monitoring strategies are introduced and as patient populations change. We developed and validated a third-generation pediatric physiology-based score for mortality risk, Pediatric Risk of Mortality III (PRISM III). DESIGN: Prospective cohort. SETTING: There were 32 pediatric intensive care units (ICUs): 16 pediatric ICUs were randomly chosen and 16 volunteered. PATIENTS: Consecutive admissions at each site were included until at least 11 deaths per site occurred. MEASUREMENTS AND MAIN RESULTS: Physiologic data included the most abnormal values from the first 12 and the second 12 hrs of ICU stay. Outcomes and descriptive data were also collected. Physiologic variables where normal values change with age were stratified by age (neonate, infant, child, adolescent). The database was randomly split into development (90%) and validation (10%) sets. Variables and their ranges were chosen by computing the risk of death (odds ratios) relative to the midrange of survivors for each physiologic variable. Univariate and multivariate statistical procedures, including multiple logistic regression analysis, were used to develop the PRISM III score and mortality risk predictors. Data were collected on 11,165 admissions (543 deaths). The PRISM III score has 17 physiologic variables subdivided into 26 ranges. The variables most predictive of mortality were minimum systolic blood pressure, abnormal pupillary reflexes, and stupor/coma. Other risk factors, including two acute and two chronic diagnoses, and four additional risk factors, were used in the final predictors. The PRISM III score and the additional risk factors were applied to the first 12 hrs of stay (PRISM III-12) and the first 24 hours of stay (PRISM III-24). The Hosmer-Lemeshow chi-square goodness-of-fit evaluations demonstrated absence of significant calibration errors (p values: PRISM III-12 development = .2496; PRISM III-24 development = .1374; PRISM III-12 validation = .4168; PRISM III-24 validation = .5504). The area under the receiver operating curve and Flora's z-statistic indicated excellent discrimination and accuracy (area under the receiver operating curve - PRISM III-12 development 947 +/- 0.007; PRISM III-24 development 0.958 +/- 0.006; PRISM III-12 validation 0.941 +/- 0.021; PRISM III-24 validation 0.944 +/- 0.021; Flora's z-statistic - PRISM III-12 validation = .7479; PRISM III-24 validation = .9225), although generally, the PRISM III-24 performed better than the PRISM III-12 models. Excellent goodness-of-fit was also found for patient groups stratified by age (significance levels: PRISM III-12 = .1622; PRISM III-24 = .4137), and by diagnosis (significance levels: PRISM III-12 = .5992; PRISM III-24 = .7939). CONCLUSIONS: PRISM III resulted in several improvements over the original PRISM. Reassessment of physiologic variables and their ranges, better age adjustment for selected variables, and additional risk factors resulted in a mortality risk model that is more accurate and discriminates better. The large number of diverse ICUs in the database indicates PRISM III is more likely to be representative of United States units.

Adolescent↗

PubMed2001

Changes in blood chemistry and hematology variables during aging in captive rhesus macaques (Macaca mulatta).

Identifying changes with age in physiological variables of captive nonhuman primates will aid in the proper treatment and clinical diagnosis of these animals, as well as enhance our understanding of nonhuman primate models for human aging. Information for 33 physiological variables was obtained from the Primate Aging Database, a multi-centered database being developed for clinical and research use. Using multiple regression analyses, we investigated the relationship of age to hematological variables, blood chemistry and body weight in 345 captive rhesus monkeys (age range 7-30 years) from three different primate research facilities. The analyses revealed that 15 of these variables show a significant relationship with chronological age and are altered in older as compared with adult animals. Here we present the first phase of a project that will: a) identify changes with age in physiological variables among adult captive rhesus macaques; and b) characterize normative values for the aging rhesus population.

Aging↗

PubMed2006

Effect of pedal rate on diurnal variations in cardiorespiratory variables.

Recently, it was observed that the freely chosen pedal rate of elite cyclists was significantly lower at 06:00 than at 18:00 h, and that ankle kinematics during cycling exhibits diurnal variation. The modification of the pedaling technique and pedal rate observed throughout the day could be brought about to limit the effect of diurnal variation on physiological variables. Imposing a pedal rate should limit the subject's possibility of adaptation and clarify the influence of time of day on physiological variables. The purpose of this study was to determine whether diurnal variation in cardiorespiratory variables depends on pedal rate. Ten male cyclists performed a submaximal 15 min exercise on a cycle ergometer (50% Wmax). Five test sessions were performed at 06:00, 10:00, 14:00, 18:00, and 22:00 h. The exercise bout was divided into three equivalent 5 min periods during which different pedal rates were imposed (70 rev x min(-1), 90 rev x min(-1) and 120 rev x min(-1)). No significant diurnal variation was observed in heart rate and oxygen consumption, whatever the pedal rate. A significant diurnal variation was observed in minute ventilation (p=0.01). In addition, the amplitude of the diurnal variation in minute ventilation depended on pedal rate: the higher the pedal rate, the greater the amplitude of its diurnal variation (p=0.03). The increase of minute ventilation throughout the day is mainly due to variation in breath frequency (p=0.01)--the diurnal variation of tidal volume (all pedal rate conditions taken together) being non-significant--but the effect of pedal rate x time of day interaction on minute ventilation specific to the higher pedal rate conditions (p=0.03) can only be explained by the increase of tidal volume throughout the day. Even though an influence of pedal rate on diurnal rhythms in overall physiological variables was not also evidenced, high pedal rate should have been imposed when diurnal variations of physiological variables in cycling were studied.

Bicycling↗

PubMed2001

Comparative analysis of multiple-casualty incident triage algorithms.

STUDY OBJECTIVE: We sought to retrospectively measure the accuracy of multiple-casualty incident (MCI) triage algorithms and their component physiologic variables in predicting adult patients with critical injury. METHODS: We performed a retrospective review of 1,144 consecutive adult patients transported by ambulance and admitted to 2 trauma centers. Association between first-recorded out-of-hospital physiologic variables and a resource-based definition of severe injury appropriate to the MCI context was determined. The association between severe injury and Triage Sieve, Simple Triage and Rapid Treatment, modified Simple Triage and Rapid Treatment, and CareFlight Triage was determined in the patient population. RESULTS: Of the physiologic variables, the Motor Component of the Glasgow Coma Scale had the strongest association with severe injury, followed by systolic blood pressure. The differences between CareFlight Triage, Simple Triage and Rapid Treatment, and modified Simple Triage and Rapid Treatment were not dramatic, with sensitivities of 82% (95% confidence interval [CI] 75% to 88%), 85% (95% CI 78% to 90%), and 84% (95% CI 76% to 89%), respectively, and specificities of 96% (95% CI 94% to 97%), 86% (95% CI 84% to 88%), and 91% (95% CI 89% to 93%), respectively. Both forms of Triage Sieve were significantly poorer predictors of severe injury. CONCLUSION: Of the physiologic variables used in the triage algorithms, the Motor Component of the Glasgow Coma Scale and systolic blood pressure had the strongest association with severe injury. CareFlight Triage, Simple Triage and Rapid Treatment, and modified Simple Triage and Rapid Treatment had similar sensitivities in predicting critical injury in designated trauma patients, but CareFlight Triage had better specificity. Because patients in a true mass casualty situation may not be completely comparable with designated trauma patients transported to emergency departments in routine circumstances, the best triage instrument in this study may not be the best in an actual MCI. These findings must be validated prospectively before their accuracy can be confirmed.

Adolescent↗

PubMed1992

Computer-assisted interpretation of visual fields in glaucoma.

Visual field abnormality is an important diagnostic sign in glaucoma. Therefore, the presence or absence of visual field loss most often strongly influences diagnostic and therapeutic decisions in glaucoma management. Interpretation of visual field results is often difficult, however. Physiological variability of perimetric sensitivity values contributes to these difficulties. It has been our aim to develop improved computer-assisted methods for the recognition of early glaucomatous field loss. Our approach has therefore been to design techniques that are highly sensitive to small but significant departures from normality. We have investigated normal physiological variability in perimetric results and combined the obtained knowledge with pathophysiological models which are sensitive to the spatial patterns of field loss commonly seen in glaucoma. Thus, we have devised probability scores in order to take the complex physiological variability into account, and developed a hemifield analysis and an arcuate cluster analysis based on the normal anatomy of the retinal nerve fibre layer. A fundamental approach in the collection of normative data and the selection of glaucoma cases used in this project has been to select subjects using non-perimetric criteria (except for the removal of large field defects). Our objective here was to reduce bias from pre-conceived ideas of visual fields. This approach was used for (1) empirical studies on physiological variability, (2) development of analysis methods, and (3) evaluation of such methods. Glaucoma patients were selected based on evaluations of optic disc appearance. Normal subjects were never eliminated on the basis of perimetric results alone. The new methods developed in these studies have significantly improved discrimination between normal and glaucomatous field results, as compared with previously available techniques. Our results indicated that the usage of probability scores was the main source of this improvement, and that the location of observed field abnormalities and spatial modelling were other important factors. Candidate methods which did not properly combine spatial and normative analyses resulted in false positive defects in the mid-periphery and/or underestimated paracentral glaucomatous field defects. Similar approaches based on classification of visual field results in terms of significances, and on recognition of specific spatial patterns of field loss could be used for other groups of diseases having visual field abnormality as an important diagnostic sign.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1996

Clinical diagnostic criteria of the adult respiratory distress syndrome in the intensive care unit.

OBJECTIVES: To determine the use of commonly used diagnostic criteria for adult/acute respiratory distress syndrome (ARDS), evaluate physiologic variables of most value in diagnosing ARDS, and assess the frequency of newly diagnosed ARDS. DESIGN: Self-administered questionnaire by mail. SETTING: Hospital intensive care units (ICUs). SUBJECTS: Intensive care physicians (n = 923) in the United States listed as ICU directors in the Society of Critical Care Medicine Membership Directory. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 448 (48.5%) physicians responded, with 301 questionnaires completed. Bilateral infiltrates on chest radiograph, the PaO2/FIO2 ratio, and pulmonary artery occlusion pressure were the most commonly used diagnostic criteria. However, the actual values used to diagnose ARDS were highly variable. The most important clinical physiologic variable used in determining the respiratory status of the ARDS patient was the PaO2/FIO2 ratio, followed by shunt fraction, alveolar-arterial oxygen tension gradient, FIO2, PaO2, respiratory system compliance, and minute ventilation. Respondents indicated that 9% of ICU beds at their institutions were occupied by a patient diagnosed with ARDS within the previous 7 days and 18.6% of all mechanically ventilated patients had ARDS by their own criteria. Based on the total number of ICU beds, the predicted incidence of ARDS would be approximately 275,000 patients per year in the United States. CONCLUSION: A wide range of diagnostic criteria are utilized by clinicians in the diagnosis of ARDS.

Adult↗

PubMed2006

A comparison of admission and worst 24-hour Acute Physiology and Chronic Health Evaluation II scores in predicting hospital mortality: a retrospective cohort study.

INTRODUCTION: The Acute Physiology and Chronic Health Evaluation (APACHE) II score is widely used in the intensive care unit (ICU) as a scoring system for research and clinical audit purposes. Physiological data for calculation of the APACHE II score are derived from the worst values in the first 24 hours after admission to the ICU. The collection of physiological data on admission only is probably logistically easier, and this approach is used by some ICUs. This study compares the performance of APACHE II scores calculated using admission data with those obtained from the worst values in the first 24 hours. MATERIALS AND METHODS: This was a retrospective cohort study using prospectively collected data from a tertiary ICU. There were no missing physiological data and follow-up for mortality was available for all patients in the database. The admission and the worst 24-hour physiological variables were used to generate the admission APACHE II score and the worst 24-hour APACHE II score, and the corresponding predicted mortality, respectively. RESULTS: There were 11,107 noncardiac surgery ICU admissions during 11 years from 1 January 1993 to 31 December 2003. The mean admission and the worst 24-hour APACHE II score were 12.7 and 15.4, and the derived predicted mortality estimates were 15.5% and 19.3%, respectively. The actual hospital mortality was 16.3%. The overall discrimination ability, as measured by the area under the receiver operating characteristic curve, of the admission APACHE II model (83.8%, 95% confidence interval = 82.9-84.7) and the worst 24-hour APACHE II model (84.6%, 95% confidence interval = 83.7-85.5) was not significantly different (P = 1.00). CONCLUSION: Substitution of the worst 24-hour physiological variables with the admission physiological variables to calculate the admission APACHE II score maintains the overall discrimination ability of the traditional APACHE II model. The admission APACHE II model represents a potential alternative model to the worst 24-hour APACHE II model in critically ill nontrauma patients.

APACHE↗