Accuracy of visual estimation of blood loss in obstetrics using clinical reconstructions: an observational simulation cohort study.

INTRODUCTION: Postpartum hemorrhage is the leading cause of maternal mortality worldwide, and optimal management requires accurate blood loss estimations. The aim of this study was to assess whether differences exist between visually estimated blood loss vs. actual blood loss based on delivery mode, blood volume or distribution/location and knowledge of patient's current cardiovascular status. METHODS: For this observational cohort study, photographs were taken of 18 blood loss scenarios for vaginal delivery and cesarean delivery, and six photographs were duplicated and annotated with maternal vital signs. Scenarios were categorized into 50% (500 mL), 100% (1000 mL) and 200% (2000 mL) of the defined blood loss volume for postpartum hemorrhage and the photographs were shown to participants to visually estimate blood loss volumes. RESULTS: The mean ±â€¯standard deviation estimates of actual 500 mL, 1000 mL and 2000 mL blood loss volumes were 1208 ±â€¯438 mL, 1676 ±â€¯630 mL and 2637 ±â€¯1123 mL, respectively (P <0.001 among groups). The difference was significantly greater in vaginal delivery than cesarean delivery scenarios (1064 ±â€¯849 mL vs. 284 ±â€¯456 mL; P <0.001). Estimated blood loss volume was not influenced by blood loss distribution/location, or by provider group or experience. The cardiovascular status of the patient impacted estimations only if tachycardia and hypotension were present. CONCLUSIONS: Most providers significantly overestimated blood loss volumes (by nearly 700 mL). Provider and scenario factors that impact inaccuracies in visual estimated blood loss identified in this study can be used to guide education and training.

Ethnic identity and its relationship to self-esteem, perceived efficacy and prosocial attitudes in early adolescence.

This study examined the relationship of ethnic identity to self-esteem, perceived self-efficacy and prosocial attitudes. The sample included 100 male and female early adolescents, ranging from 11 to 13 years old, from different racial/ethnic backgrounds. Structural equations modeling was used to examine the latent structure of the multi-dimensional constructs and their interrelationships. Self-esteem and ethnic identity factors emerged which were related and which evidenced efficacy-mediated effects upon prosocial attitudes. The findings suggested that ethnic identity and self-esteem are distinct but related contributors to young people's perceptions of their ability to achieve academically, to find meaningful careers and to value prosocial means of goal attainment.

Use of the "fast evaluation of mobility, balance, and fear" in elderly community dwellers: validity and reliability.

BACKGROUND AND PURPOSE: Identifying elderly community dwellers who are at risk for falling was assessed using a comprehensive screening tool referred to as the "Fast Evaluation of Mobility, Balance, and Fear" (FEMBAF). The purpose of this study was to evaluate the concurrent validity and reliability of scores on the FEMBAF. SUBJECTS: Thirty-five elderly persons living in the community (4 men, 31 women), with a mean age 79.9 years (SD = 8.5, range = 60-92), participated. METHODS: Subjects were tested using the FEMBAF and three other instruments-the balance subscale of the Tinetti Performance-Oriented Mobility Assessment (B-POMA), the Clinical Test of Sensory Interaction on Balance (CTSIB), and the Timed Up and Go Test. Scores on the FEMBAF were compared with scores on each the other instruments using Spearman rank-order correlation coefficients and analysis of covariance (with age as the covariate) for living status and diagnostic category. A comparison of the number of subjects classified as being at risk for falling was done descriptively for the FEMBAF, B-POMA, and CTSIB. RESULTS: Associations (r > .35) were found between the FEMBAF and each of the other instruments in the areas of FEMBAF risk-factor count, task completion, mobility, and strength. The FEMBAF classified a greater number of subjects as being at risk for falling (89%) compared with the B-POMA (43%) and the CTSIB (63%). The mean chance-corrected percentage of agreement between raters on the FEMBAF was kappa = .95 (SD = .15) for assessment of risk factors and kappa = .96 (SD = .12) for task completion. CONCLUSION AND DISCUSSION: The FEMBAF provides valid and reliable measurements of risk factors, functional performance, and factors that hinder mobility.

Prospective, randomized, double-blind, placebo-controlled comparison of metoclopramide and ondansetron for prevention of posttonsillectomy or adenotonsillectomy emesis.

STUDY OBJECTIVE: To compare the antimetic efficacy of prophylactic ondansetron, metoclopramide, and placebo for prevention of postoperative vomiting in pediatric tonsillectomy or adenotonsillectomy patients. DESIGN: Prospective, randomized, double-blind, placebo controlled study. SETTING: Children's hospital. PATIENTS: 132 ASA status I and II children, ages 2 to 12 years, undergoing tonsillectomy or adenotonsillectomy. INTERVENTIONS: Patients received intravenous (IV) melodopramide 0.25 mg/kg, IV on dansetron 0.15 mg/kg, or IV saline placebo after induction of standardized halothane, nitrous oxide, and oxygen anesthesia. Muscle relaxants and their antagonists were allowed. Patients received postoperative analgesics as needed. MEASUREMENTS AND MAIN RESULTS: Incidence of postoperative vomiting, time of vomitting onset, and hospital length of stay (LOS) were measured. Patients who were admitted were excluded from LOS analysis. The postoperative incidence of vomiting was 54% for patients receiving metoclopramide, 26% for patients receiving ondansetron, and 69% for the placebo group. These differences were significant for ondansetron versus metoclopramide (p = 0.008) and placebo (p = 0.001). The mean (SD) LOS was significantly shorter for patients not vomiting 488 (88) minutes for vomiters versus 435 (65) minutes for non-vomiters. CONCLUSIONS: Prophylactic ondansetron is more effective than metoclopramide or placebo for the prevention of vomiting after tonsillectomy or adenotonsillectomy. Patients who do not vomit postoperatively have shorter LOS.

Pharmacokinetics of fluconazole in immune-compromised children with leukemia or other hematologic diseases.

STUDY OBJECTIVE: To describe the pharmacokinetics of fluconazole in immune-compromised children with leukemia or other hematologic disease. DESIGN: Prospective. SETTING: Children's Health Care-Minneapolis hematology/oncology inpatient ward and outpatient clinic. PATIENTS: Ten immune-compromised children (mean +/- SD age 7.4 +/- 4.0 yrs, weight 31.6 +/- 25.9 kg) with leukemia or other hematologic disease. INTERVENTIONS: Serum was sampled before and after a single 6-mg/kg intravenous dose and after seven oral 3-mg/kg doses of fluconazole. MEASUREMENTS AND MAIN RESULTS: Mean (SD) pharmacokinetics were distribution half-life 1.67 (1.25) hours, elimination half-life 15.62 (3.21) hours, total body clearance 0.63 (0.19) ml/min/kg, volume of distribution for the central compartment 0.56 (0.10) L/kg, volume of distribution at steady state 0.77 (0.12) L/kg, absorption half-life 0.41 (0.26) hour, and oral bioavailability 0.92 (0.09). Volume of distribution for the central compartment was highly correlated with body surface area (r2 = 0.891) and weight (r2 = 0.949). Volume of distribution at steady state correlated with body surface area (r2 = 0.986), and total body clearance correlated with body surface area (r2 = 0.867). CONCLUSIONS: Fluconazole elimination was well described using a two-compartment model. Oral absorption was rapid and nearly complete. Children have a larger volume of distribution for the central compartment and faster elimination rate than adults. Body surface area and weight are important factors in determining pharmacokinetics in these patients.

Population pharmacokinetics of vancomycin in neonates.

OBJECTIVE: To determine population pharmacokinetic parameters of vancomycin in neonates. METHODS: This was a retrospective design, with prospective validation. Two hundred ten sequential neonates were evaluated at the neonatal intensive care units of Minneapolis Children's Medical Center and Children's Hospital of St. Paul. Five hundred twenty serum concentrations from 192 patients were included. A mean +/- SD gestational age of 29.5 +/- 5.1 weeks, postnatal age of 16.5 +/- 19.6 days, and dosing weight of 1492 +/- 1053 gm described the population. Thirty additional patients were studied for validation. Dosing, serum concentrations, and 28 covariates were collected. Data were evaluated with NONMEM. Forward selection and backward elimination regression identified significant covariates. One- and two-compartment population pharmacokinetic parameters and predictive performance of the models were measured. RESULTS: Two-compartment final regression equations were as follows: Clearance (CL) = 0.0590 L/kg/hr (multiplied by 0.460 if exposed to dopamine and 0.643 if gestational age was < or = 32 weeks), central volume (VC) = 0.440 L/kg, intercompartmental clearance (Q) = 0.0313 L/hr/kg, and steady-state volume of distribution (Vss) = 0.764 L/kg. Interindividual variability was 40.6% for CL, 54.1% for Vss, and 16.8% for VC. Residual variability was 3.3 micrograms/ml. One-compartment final regression equations were: CL = 0.0626 L/kg/hr (multiplied by 0.455 if exposed to dopamine and 0.656 if gestational age was < or = 32 weeks), and Vd = 0.496 L/kg. Differences in relative performance were insignificant by use of one- or two-compartment parameters. CONCLUSIONS: Gestational age < or = 32 weeks and concurrent use of dopamine were significant factors in prediction of vancomycin clearance. alpha Half-lives of 2.8 to 3.7 hours and beta half-lives of 13.4 to 33.7 hours suggest that some individuals in this neonatal population have considerably longer half-lives than those previously reported.

Predictive performance of three methods of activated clotting time measurement in neonatal ECMO patients.

Previously reported activated clotting time (ACT) data in adults demonstrated higher values with the HemoTec LRACT (HT) and TriMed ACTivator (TM) techniques than with the Hemochron System P214/215 (HC) technique throughout a range of heparin concentrations. This study sought to determine if a difference exists in ACT values of neonatal patients receiving ECMO. ACTs were performed in nine neonatal ECMO patients using the HC, HT, and TM techniques. Techniques were compared for positive or negative direction of any prediction difference (bias), and the typical value of a difference (precision). Simultaneous, duplicate, morning, and afternoon ACT comparisons were obtained using all three techniques. Forty-six comparisons of HC values in the 180-240 sec range were analyzed. All techniques produced results different from the same sample. The HT and TM techniques were upwardly biased by 51 and 148 sec, respectively, when evaluated against HC. HT was negatively biased by 123 sec when evaluated against TM. Because ACT values vary among techniques, ACT target ranges should be technique specific. Future references to ACT data should identify the equipment and procedures employed.

The effect of heparin on three whole blood activated clotting tests and thrombin time.

Whole blood activated clotting time (ACT) can be determined by many different methods that use a variety of clotting cascade activators and end-points. This study compared the results of three whole blood ACT instruments at equivalent concentrations of heparin. Whole blood (9.8 ml) from 10 healthy adult volunteers without coagulation abnormalities was added to 0.2 ml of heparin solution producing heparin concentrations of 0, 0.1, 0.2, 0.4, 0.6, 0.8, and 1.0 U/ml. Coagulation status was determined in duplicate with the Hemochron 400 System (HC), the HemoTec Automated Coagulation Timer (HT), and the TriMed ACTivator (TM). Thrombin times or dilutions (TT) were also determined for each sample. Baseline values did not differ (p greater than 0.05); however, the HT and TM ACT values were significantly longer (p less than 0.05) than the HC ACT values at predicted heparin concentrations greater than 0.2 U/ml. Results from the HT and TM instruments were not significantly different. The HT and TM instruments both provided a greater ACT range over the heparin concentrations tested. Of the tests studied to monitor heparin therapy, mean scaled TTs showed the best correlation with predicted heparin concentrations.

Effect of drinking water temperature on broiler performance.

In the first experiment, higher body weight gain and feed comsumption were attained with water at a temperature of 23.9 degrees C. as compared with 35.0 degrees C. No significant differences in feed efficiency due to water temperature were evident. Livability was significantly reduced during brooding for the birds given warm water (35.0 degree C). A significant interaction for body weight gain was observed between the initial ambient air brooding temperatures and water temperatures during the growing period. In the second experiment six water temperatures during brooding to three weeks of age were studied. Body weight gain and feed comsumption were significantly depressed at a drinking water temperature of 40.6 degrees C. as compared with drinking water temperatures between 17.8 degrees C. and 35.0 degrees C. No differences in livability were noted which was in contrast to the results of the first experiment. A drinking water temperature below ambient air temperature is apparently beneficial to the growth of the broiler chick. The placement of the waterers in relation to the brooder stoves could influence water temperature which would affect the growth of broilers.