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At least 991 records · Page 55Linked to original sources
PubMed1992

Accuracy of text entries within a manually compiled anaesthetic record.

We have examined the accuracy of text entries within a manually compiled anaesthetic record by comparing the record of the anaesthetist with that of an observer, present throughout the procedure but whose sole purpose was the documentation of perioperative events. Eighty-six items of information were analysed for accuracy from 197 records. The mean proportion of omissions was 35% and the mean proportion of incorrect entries was 3.4%. Where no entry should have been made, the mean proportion of unwarranted entries was 1%. Accuracy varied according to the information contained; however, omissions were common for preoperative status, fluids, tourniquet use, aspects of monitoring, local anaesthesia and intraoperative problems. The most consistently accurate information was the description of the patient and that relating to intraoperative i.v. drug use. Inaccuracy was common for the majority of sites on the record, irrespective of their reflecting on the anaesthetist's performance. We suggest, therefore, that the reason for this inaccuracy of data was not related principally to anaesthetists' defensiveness, but may reflect their attitudes to the record's value and response to inadequacies in its design. The observed deficiencies in recording accuracy may affect patient safety during future anaesthesia and has relevance to medico-legal and epidemiological research.

Anesthesia↗
PubMed1998

Accuracy and precision of "deep sternal" and tracheal temperatures at high- and low-fresh-gas flows.

The accuracy of tracheal temperature as a measure of core temperature is relatively poor during high-flow ventilation (6 litre min-1 fresh-gas flow). It is unknown if accuracy improves when lower fresh-gas flow rates are used. We tested the hypothesis that tracheal temperature accuracy would improve with low-flow ventilation (1 litre min-1). We studied 20 ASA Physical Status I and II patients undergoing general anaesthesia for lower abdominal surgery. Deep body temperatures were measured at the middle of the sternum using a Coretemp "deep-tissue" thermometer. Tracheal temperatures were monitored from thermistors incorporated into the tracheal tube cuffs. Oesophageal temperatures were measured from thermocouples incorporated into stethoscopes positioned at the point of maximal heart sounds. Sternal temperature correlated reasonably well with distal oesophageal temperatures, both being within the 0.5 degree C cut-off for accuracy and precision. Tracheal temperatures were lower than oesophageal temperatures during both high- and low-flow ventilation. Tracheal temperatures were 0.7 degree C less during high-flow ventilation and 0.9 degree C less during low-flow ventilation. The precision in both cases was adequate. We conclude that tracheal temperatures were insufficiently accurate for routine clinical use, even when fresh- gas flow was restricted to 1 litre min-1. In contrast, the deep temperatures were sufficiently accurate and precise for routine clinical use.

Adult↗
PubMed1999

The diagnostic accuracy of Danish GPs in the diagnosis of pigmented skin lesions.

BACKGROUND: The GP often has a primary function in assessing pigmented skin lesions in Denmark. No data are available on the diagnostic accuracy of this process. OBJECTIVE: We aimed to study the sensitivity, specificity and positive prognostic value of the diagnosis made by 27 trained or trainee GPs. METHOD: We tested the diagnostic accuracy of the viewing of colour slides of pigmented skin lesions under standardized conditions at a seminar on skin cancer. Diagnostic accuracy was determined only for the clinically relevant diagnosis of benign or malignant. RESULTS: The median diagnostic accuracy (sensitivity) for the group as a whole was 0.75 (95% CI 0.65-0.80), the specificity was 0.70 (95% CI 0.68-0.79) and the positive predictive value 0.70 (95% CI 0.62-0.77). CONCLUSION: These values are comparable with previously published figures for trainee dermatologists, and it is therefore concluded that ongoing interest rather than basic training is the major determinant for clinical acumen.

Adult↗
PubMed2001

Towards improvement of the accuracy and completeness of medication registration with the use of an electronic medical record (EMR).

BACKGROUND: Approximately 80% of GPs use a GP information system (GIS) and an electronic medical record (EMR) in their daily practice. To reap the full benefits of an EMR for patient care, post-graduate education and research, the data input must be well structured and accurately coded. OBJECTIVES: The quality and user-friendliness of the software positively influence the completeness and reliability of the data recorded in the GIS. To assess this in actual practice, this study examined whether or not an increase occurred in the accuracy and completeness of indication-related medication registration after the GIS's software package was upgraded. METHOD: GPs recorded data for the Registration Network Groningen (RNG) concerning four medication groups: insulin, trimethoprim, the contraceptive pill and beta-blocking agents. The completeness and accuracy of the registered data were assessed both before and after the change to the new software package. The completeness is evaluated on the basis of the indications missing for the prescribed medications. To assess accuracy, a check was made to determine whether the indications corresponded to those deemed relevant for that particular medication according to National Pharmaceutical Guidelines. RESULTS: The percentage of missing indications decreased notably, especially in the chronically prescribed medication groups. For insulin, the percentage decreased from 40.5 to 3% and for the contraceptive pill from 34.5 to 1%. For trimethoprim, the percentage decreased from 10 to 1%, and for beta-blocking agents from 22 to 1.5%. Of the indications present, the percentage of relevant indications showed a slight increase, with the largest increase observed for the contraceptive pill where the percentage rose from 86 to 96%. CONCLUSIONS: The completeness of recorded indications improved considerably after the change of software. This is due mostly to the efforts of the GPs, their practice assistants and the support of the RNG organization involved in the conversion procedure. Accuracy improved slightly, especially due to the software modifications which ensured that non-existent codes could not be entered. To summarize, with increased user-friendliness of the software, combined with the training of motivated GPs, the quality of recorded data improved.

Adrenergic Antagonists↗
PubMed1995

Alterations in ribosomal protein RPS28 can diversely affect translational accuracy in Saccharomyces cerevisiae.

Three small-subunit ribosomal proteins shown to influence translational accuracy in Saccharomyces cerevisiae are conserved in structure and function with their procaryotic counterparts. One of these, encoded by RPS28A and RPS28B (RPS28), is comparable to bacterial S12. The others, encoded by sup44 (RPS4) or, sup46 and YS11A (RPS13), are homologues of procaryotic S5 and S4, respectively. In Escherichia coli, certain alterations in S12 cause hyperaccurate translation or antibiotic resistance that can be counteracted by other changes in S5 or S4 that reduce translational accuracy. Using site-directed and random mutagenesis, we show that different changes in RPS28 can have diametrical influences on translational accuracy or antibiotic sensitivity in yeast. Certain substitutions in the amino-terminal portion of the protein, which is diverged from the procaryotic homologues, cause varying levels of nonsense suppression or antibiotic sensitivity. Other alterations, found in the more conserved carboxyl-terminal portion, counteract SUP44- or SUP46-associated antibiotic sensitivity, mimicking E. coli results. Although mutations in these different parts of RPS28 have opposite affects on translational accuracy or antibiotic sensitivity, additive phenotypes can be observed when opposing mutations are combined in the same protein.

Amino Acid Sequence↗
PubMed1998

The accuracy of marker-assisted selection for quantitative traits within populations in linkage equilibrium.

Using the concept of conditional coancestry, given observed markers, an explicit expression of the accuracy of marker-based selection is derived in situations of linkage equilibrium between markers and quantitative trait loci (QTL), for the general case of full-sib families nested within half-sib families. Such a selection scheme is rather inaccurate for moderate values of family sizes and QTL variance, and the accuracies predicted for linkage disequilibrium can never be reached. The result is used to predict the accuracy of marker-assisted combined selection (MACS) and is shown to agree with previous MACS results obtained by simulation of a best linear unbiased prediction animal model. Low gains in accuracy are generally to be expected compared to standard combined selection. The maximum gain, assuming infinite family size and all QTLs marked, is about 50%.

Genetic Linkage↗
PubMed1997

Accuracy of nurse aides' functional health assessments of nursing home residents.

BACKGROUND: Nurse aides provide assessments of nursing home residents' functional health for use in care planning and quality assurance. Nurse practitioner assessments can serve as a standard for analysis of nurse aides' accuracy. This study compared nurse aide to nurse practitioner assessments of nursing home residents' functional health with regard to possible bias and extent of correlation. METHODS: Nurse aides' accuracy in assessing nursing home residents' activities of daily living was evaluated by comparisons to assessments performed by a master's-prepared nurse practitioner using four functional assessment instruments: the Barthel Index, the Katz Index of Activities of Daily Living, the Multidimensional Observation Scale for Elderly Subjects, and the Scaled Outcome Criteria. Data were collected in a 159-bed nonprofit nursing home licensed for skilled and intermediate care. Residents had a wide variety of functional and cognitive abilities and disabilities. Ninety-six nursing home residents provided data for the study. Functional health assessments by 24 nurse aides, each assessing 4 different nursing home residents, were compared to those of 1 nurse practitioner. Statistical analysis of accuracy used paired samples t-tests and Pearson product moment correlation coefficients. RESULTS: Nurse aide assessments and nurse practitioner assessments were highly correlated. Most functional health assessments evidenced no significant nurse aide bias. When bias was present it usually resulted from nurse aides electing more optimistic choices when using an assessment instrument that offered fewer response levels for rating residents. CONCLUSIONS: Nurse aides can accurately use well-calibrated instruments to assess nursing home residents' functional health. Demonstration of assessment accuracy in nurse aides, who provide the majority of direct care for nursing home residents, documented a valuable clinical resource for planning and evaluating resident care.

Activities of Daily Living↗
PubMed1999

The effects of circumferential wrist pressure on reproduction accuracy of wrist placement in healthy young and elderly adults.

BACKGROUND: The purpose of this study was to determine the effect of circumferential wrist pressure on reproduction accuracy of wrist placement in healthy young and elderly adults. A convenience sample of 20 young adults having a mean age of 22.9 years and 20 elderly adults with a mean age of 68.2 years participated in the study. METHOD: Blindfolded subjects were asked to actively self-select a neutral wrist position (reference) and then, when signaled, to actively reproduce the previously selected position. Wrist joint reproduction accuracy was assessed under four pressure conditions: no contact, wrist contact, 10 mm Hg, and 20 mm Hg. A single axis dynamic wrist electrogoniometer measured three dependent variables: absolute, constant, and variable errors. Data were analyzed by means of multivariate analysis of variance (MANOVA) for repeated measures. RESULTS: No significant differences in reproduction accuracy under the four pressure conditions for young or elderly adults were found. CONCLUSIONS: Healthy young and elderly adults may utilize existing intrinsic feedback and central control mechanisms to achieve accuracy during a reproduction task. Some subjects in both age groups who entered into the study with high error scores benefited from circumferential pressure by possibly relying on peripheral mechanisms. Further studies are needed to determine the effect of circumferential pressure on subjects with poor reproduction performance.

Adolescent↗
PubMed2005

Prediction of coronary events in a low incidence population. Assessing accuracy of the CUORE Cohort Study prediction equation.

BACKGROUND: The aims of this paper are to derive a 10-year coronary risk predictive equation for adult Italian men, and to assess its accuracy in comparison with the Framingham Heart Study (FHS) and PROCAM study equations. METHODS: The CUORE study is a prospective fixed-cohort study. Eleven cohorts, from the north and the centre-south of Italy, had been investigated at baseline between 1982 and 1996, adopting MONICA methods to measure risk factors. Among this sample of 6865 men, aged 35-69 years and free of coronary heart disease (CHD) at baseline, 312 first fatal and non-fatal major coronary events occurred in 9.1 years median follow-up. Calibration, as the difference between 10-year predicted and actual risk, and discrimination, as the ability of the risk functions to separate high-risk from low-risk subjects, have been assessed to compare accuracy of the FHS, the PROCAM, and the CUORE study equations. RESULTS: The best CUORE equation includes age, total cholesterol, systolic blood pressure, cigarette smoking, HDL-cholesterol, diabetes mellitus, hypertension drug treatment, and family history of CHD (area under the ROC curve = 0.75). The uncalibrated estimates of the 10-year risk in this CUORE follow-up data were 0.093 and 0.109 higher (P < 0.05) from the Framingham and PROCAM risk scores, respectively, than the Kaplan-Meier estimate for CUORE, indicating risk overestimates for both equations. Standard recalibration techniques improved accuracy of the FHS equation only. PROCAM overestimates were prominent in the higher risk deciles. With an alternative method for recalibration better risk estimates were obtained, but a cohort study was needed to obtain a properly calibrated risk equation. CONCLUSIONS: The CUORE Project predictive equation showed better accuracy of the FHS and PROCAM equations, overcoming frequently reported risk overestimates. The CUORE equation may be adopted to identify men with high coronary risk in Italy.

Adult↗
PubMedDate not supplied

Blood glucose estimations in adolescents with type 1 diabetes: predictors of accuracy and error.

OBJECTIVE: To examine predictors of blood glucose (BG) estimation accuracy and errors in adolescents with Type 1 diabetes. METHOD: Seventy-eight adolescents (ages 11-19) rated their physical symptoms and estimated their BG prior to conducting daily BG tests. BG estimation data were subject to an error grid analysis. Hierarchical regression was used to identify predictors of BG estimation accuracy and errors. RESULTS: The average participant made accurate BG estimations 37% of the time and clinically relevant BG estimation errors 24% of the time. Girls and older adolescents had higher BG estimation accuracy rates and lower BG estimation error rates than boys and younger adolescents. Higher BG variability was also associated with increased BG estimation errors. CONCLUSIONS: Although boys, younger adolescents, and those with higher BG variability showed higher BG estimation error rates, most participants showed low rates of BG estimation accuracy and high rates of BG estimation error. Health providers may underestimate the frequency of inappropriate self-treatment as a result of patient difficulty in estimating BG accurately.

Adolescent↗
PubMed2005

Advancing the science of perceptual accuracy in pediatric asthma and diabetes.

OBJECTIVES: To review research on perceptual accuracy in pediatric asthma and diabetes and to provide recommendations for future research efforts and clinical applications of the construct in these populations. METHODS: A literature search was conducted using Medline and PsychInfo databases as well as the bibliographies of relevant articles. RESULTS: Children and adolescents with asthma or diabetes evidence considerable variability in perceptual accuracy and frequently make clinically relevant errors that have the potential to affect self-management behavior. CONCLUSIONS: Recommendations for future research include studying distinct types of perceptual errors, empirically supporting the relationship between perceptual accuracy and relevant outcomes, identifying factors related to perceptual inaccuracy, and conducting longitudinal research and intervention studies. Recommendations for applying the construct in clinical practice include adopting an individualized approach to symptoms to guide patient education and management, identifying patients prone to making clinically relevant errors, and developing and implementing interventions to improve accuracy.

Adolescent↗
PubMed2005

Accuracy of coalescent likelihood estimates: do we need more sites, more sequences, or more loci?

A computer simulation study has been made of the accuracy of estimates of Theta = 4Nemu from a sample from a single isolated population of finite size. The accuracies turn out to be well predicted by a formula developed by Fu and Li, who used optimistic assumptions. Their formulas are restated in terms of accuracy, defined here as the reciprocal of the squared coefficient of variation. This should be proportional to sample size when the entities sampled provide independent information. Using these formulas for accuracy, the sampling strategy for estimation of Theta can be investigated. Two models for cost have been used, a cost-per-base model and a cost-per-read model. The former would lead us to prefer to have a very large number of loci, each one base long. The latter, which is more realistic, causes us to prefer to have one read per locus and an optimum sample size which declines as costs of sampling organisms increase. For realistic values, the optimum sample size is 8 or fewer individuals. This is quite close to the results obtained by Pluzhnikov and Donnelly for a cost-per-base model, evaluating other estimators of Theta. It can be understood by considering that the resources spent collecting larger samples prevent us from considering more loci. An examination of the efficiency of Watterson's estimator of Theta was also made, and it was found to be reasonably efficient when the number of mutants per generation in the sequence in the whole population is less than 2.5.

Genetic Variation↗
PubMed1990

The accuracy and precision of the Accutracker ambulatory blood pressure monitor.

Prerequisite to the use of ambulatory blood pressure monitors in epidemiologic research is demonstration of a satisfactory level of accuracy and precision. Previous evaluations of these devices raise a number of methodological concerns which complicate interpretation of their findings. Also, important issues regarding the precision of blood pressure measurements and the identification of factors associated with measurement inaccuracies remain unaddressed. To assess the accuracy and precision of the Accutracker ambulatory blood pressure monitor, we obtained five serial estimates of resting blood pressure on 120 ambulatory subjects in The Johns Hopkins Medical Institutions in 1987. Two Accutrackers and two manual observers independently recorded blood pressure with the order determined at random. The fourth observer in each sequence obtained a replicate measurement. For both systolic and diastolic blood pressures, the mean difference between Accutracker and manual measurements was less than 3 mmHg for each pairwise comparison. Scatter plots and regression analyses demonstrated that both Accutrackers tended to underestimate high systolic and diastolic blood pressures. In bivariate and multivariate analyses, increased age was significantly associated with underestimation of systolic blood pressures by both Accutrackers. With respect to the precision of blood pressure measurement, no significant differences were present among the four observers. In summary, our data suggest that the Accutracker has satisfactory accuracy and precision, but that accuracy is not uniform across patient subgroups.

Adult↗
PubMed2000

The accuracy and precision of body temperature monitoring methods during regional and general anesthesia.

UNLABELLED: We tested the hypotheses that accuracy and precision of available temperature monitoring methods are different between spinal anesthesia (SA) and general anesthesia (GA), and that patients receiving SA are at equal risk for hypothermia as those receiving GA. Patients scheduled for radical retropubic prostatectomy were enrolled. Either GA (n = 16) or SA (n = 16) was given according to patient and clinician preference. Temperatures were monitored with thermocouple probes at the tympanic membrane, axilla, rectum, and forehead skin surface. Tympanic temperatures were also measured with an infrared device, and forehead skin temperatures were monitored with two brands of liquid crystal thermometer strips. Accuracy and precision of these monitoring methods were determined by using tympanic membrane temperature, measured by thermocouple, as the reference core temperature (T(c)). At the end of surgery, T(c) was similar between SA (35.0 +/- 0.1 degrees C) and GA (35.2 +/- 0.1 degrees C) (P = 0.44). Accuracy and precision of each temperature monitoring method were similar between SA and GA. Rectal temperature monitoring offered the greatest combination of accuracy and precision. All other methods underestimated T(c). These findings suggest that patients receiving SA or GA are at equal and significant risk for hypothermia, and should have their temperatures carefully monitored, recognizing that most monitoring methods underestimate T(c). IMPLICATIONS: Body temperature should be monitored during spinal anesthesia because patients are at significant risk for hypothermia. Rectal temperature is a valid method of measuring core temperature, whereas other methods tend to underestimate true core temperature.

Anesthesia, General↗
PubMed2001

The accuracy of coagulation tests during spinal fusion and instrumentation.

UNLABELLED: Patients undergoing major spine surgery may acquire a perioperative coagulopathy from dilution of coagulation factors and/or platelets or fibrinolysis. The mechanisms of the coagulopathy and role of coagulation testing during these procedures are poorly defined. Theoretically, coagulation tests could be used perioperatively to determine which patients are at risk for significant bleeding and guide transfusion therapy. We retrospectively evaluated the sensitivity, specificity, and accuracy of coagulation tests in predicting excessive surgical bleeding in 244 consecutive patients undergoing thoracic, lumbar, or sacral spinal fusion with or without instrumentation. Excessive bleeding was reported by the surgeon in 39 of the patients and was defined as recurrent microvascular bleeding despite adequate use of electrocautery and suture or decreased clot formation of blood pooled within the surgical field. Patients with excessive clinical bleeding sustained larger estimated blood losses than those with normal hemostasis. The total number of allogeneic red blood cells, platelets, and fresh frozen plasma units were also larger in patients with excessive bleeding noted during surgery. The intraoperative coagulation tests with the most sensitivity and specificity were the international normalized ratio (INR), prothrombin time (PT), and activated partial thromboplastin time (aPTT). The INR had a sensitivity of 94%, a specificity of 88%, and an accuracy of 0.9 at a value of 1.4 (normal, 0.8-1.2). The PT had a sensitivity of 90%, a specificity of 64%, and an accuracy of 0.73 at a value of 13.5 s (normal, 8.4-12.0 s). The aPTT had a sensitivity of 85%, a specificity of 64%, and an accuracy of 0.71 at a value of 30.9 s (normal, 23-37 s). The thromboelastogram values were of marginal use. We conclude that the INR, PT, and aPTT may be helpful in guiding transfusion therapy in patients undergoing major spine surgery. IMPLICATIONS: Patients undergoing major surgery to the spine often acquire a perioperative coagulopathy. The prothrombin time and activated partial thromboplastin time had the greatest sensitivity and specificity for predicting bleeding in major surgery of the spine. The test values that differentiated normal from excessively bleeding patients could be used to guide transfusion therapy during surgery.

Adolescent↗
PubMed2002

The delivery rate accuracy of portable infusion pumps used for continuous regional analgesia.

UNLABELLED: Portable pumps used for local anesthetic infusion during continuous regional analgesia are gaining acceptance. These pumps are often used for ambulatory patients who are medically unsupervised throughout most of the infusion. However, the performance of these pumps, which infuse potentially toxic medication, has not been independently investigated. We investigated the flow rate accuracy, consistency, and profiles of various portable pumps often used for local anesthetic infusion during continuous regional analgesia. By using a computer/scale combination within a laboratory to record infusion rates, 6 pumps were tested with their flow regulators at expected (30 degrees-32 degrees C) and increased (34 degrees-36 degrees C) temperatures. Infusion rate accuracy differed significantly among the pumps, exhibiting flow rates within +/-15% of their expected rate for 18%-100% of their infusion duration. An increase in temperature also affected pumps to differing degrees, with infusion rates increasing from 0% to 25% for each model tested. These results suggest that factors such as flow rate accuracy and consistency, infusion profile, and temperature sensitivity should be considered when choosing and using a portable infusion pump for local anesthetic administration. IMPLICATIONS: Portable pumps often used for local anesthetic infusion during continuous regional analgesia exhibit varying degrees of delivery rate accuracy and consistency. Furthermore, increases in temperature result in an increased infusion rate for various pumps investigated. These factors should be taken into consideration when choosing and using a portable infusion pump.

Anesthesia, Conduction↗
PubMed1995

Accuracy of disposable blood pressure transducers used in the critical care setting.

OBJECTIVES: To assess the initial accuracy, drift in calibration over several hours, and decline in accuracy over daily use of blood pressure transducers used in the critical care setting. DESIGN: Prospective, criterion standard. SETTING: Three critical care units in a university hospital. SUBJECTS: Twenty-seven consecutively available high-pressure transducers were used to measure intra-arterial blood pressures, and 11 consecutively available low-pressure transducers were used to measure central venous and pulmonary arterial blood pressures. INTERVENTIONS: High-pressure transducers were compared with a mercury column manometer, and low-pressure transducers were compared with a water column manometer at three pressure levels. Data were collected initially after installation of the pressure transducer, at 3 hrs, and at 6 hrs. Data collections were repeated on subsequent days. MEASUREMENTS AND MAIN RESULTS: a) The majority of pressure transducers are accurate; b) there is no drift in the accuracy of pressure transducers over several hours; c) the accuracy of pressure transducers does not decline over subsequent days. Some transducers over-estimated standard pressures by 10 mm Hg and/or underestimated standard pressure by 17 mm Hg. CONCLUSIONS: The majority of pressure transducers used in the critical care setting are accurate, although there are some transducers that may compromise patient care. Blood pressure transducers should be checked against a standard manometer upon installation, and daily during use.

Blood Pressure Determination↗
PubMed1999

Blood volume determination by the carbon monoxide method using a new delivery system: accuracy in critically ill humans and precision in an animal model.

OBJECTIVE: To evaluate accuracy and repeatability of blood volume determinations made by the carbon monoxide method, using a ventilator-driven administration system. DESIGN: Prospective within-patient comparison, using simultaneous measurements by two methods to determine accuracy. Prospective laboratory investigation in animals to estimate repeatability. SUBJECTS: For accuracy: Nineteen ventilated critically ill patients in a university hospital intensive care unit. For repeatability: Six anesthetized, mechanically ventilated normovolemic pigs because this is impossible to perform in humans. INTERVENTIONS: In the accuracy study, a small mass of carbon monoxide was administered via a closed breathing system and arterial blood samples were taken from existing cannulas. In the repeatability study, an intramuscular sedative was given, followed by an inhalational anesthetic induction and mechanical ventilation via a tracheal tube. Left axillary artery and external jugular vein cannulas were sited. Anesthesia was maintained using an intravenous infusion. Five sequential circulating hemoglobin and blood volume estimations were made using the carbon monoxide method. MEASUREMENTS AND MAIN RESULTS: The small carboxyhemoglobin increase produced by uptake of a small, known mass of carbon monoxide was used to estimate the circulating blood volume. Simultaneous measurement, using 51Cr-labeled red blood cells, was performed. Twenty measurements were made in 19 patients. The bias (mean difference between blood volume measurements by the two methods) was 397 mL (5.53 mL x kg(-1)) +/-415 mL (+/-5.95 mL x kg(-1)); the limits of agreement (mean difference +/-2 SD) were -433 mL and 1227 mL (-6.36 mL x kg(-1) and 17.42 mL x kg(-1)). Therefore, 95% of expected differences will lie between these limits. The mean blood volume was 75.8 mL x kg(-1) in the animals. The coefficient of variation of repeated estimates was 9.49%. Mean circulating hemoglobin mass was 7.31 mmol with a coefficient of variation of 10.18%. The mean hemoglobin concentration, by co-oximetry, was 5.014 mmol x L(-1), coefficient of variation, 2.99%. CONCLUSION: This arrangement is a potential bedside method of estimating blood volume and circulating hemoglobin mass. We have rendered the technique more acceptable clinically by creating a ventilator-driven administration system.

Administration, Inhalation↗