Comparison of pleural fluid pH values obtained using blood gas machine, pH meter, and pH indicator strip

STUDY PURPOSE: The purpose of this study was to compare the pleural fluid pH values obtained with a blood gas machine (pHbg), with a pH meter (pHmet), and with a pH indicator strip (pHstrip), to determine if the pleural fluid pH measured by a pH meter or a pH indicator strip was sufficiently accurate for clinical decisions. METHODS: The pleural fluid pH was determined, within 20 min after being collected anaerobically, by a blood gas machine (CIBA-Corning model 288), pH meter (Corning pH meter 610A), and pH indicator strip (Baxter Diagnostic) following routine laboratory procedures in 50 pleural fluids. Pleural fluid pH was determined in seven additional samples with the blood gas machine and a pH meter at 25 and 37 degrees C respectively, initially, and after 30 min. RESULTS: The mean pHbg (7.42+/-0.01) was significantly less than the mean pHmet (7.58+/-0.02) or the mean pHstrip (8.23+/-0.06). There were significant differences between the pHbg and the pHmet (p < 0.001), and between the pHbg and the pHstrip (p < 0.001). Analysis of the additional seven samples demonstrated that when the blood gas machine was set at 25 degrees C, the pHbg (pHbg = 7.54+/-0.02) and the pHmet (7.53+/-0.01) were almost identical. CONCLUSION: When the pleural fluid pH is going to be used for decision making, only the pH values provided by the blood gas machine are sufficiently accurate.     

Neuron-specific enolase: reference values in cord blood

OBJECTIVE: This retrospective analysis was designed to optimize the parameters and techniques required to successfully perform high-quality coincidence imaging in a general nuclear medicine department using a dual-headed gamma camera. METHOD: Coincidence imaging was performed on 33 patients after an intravenous injection of 3.0-5.0 mCi fluoro-2-deoxyglucose (18F-FDG). Data for all subjects were evaluated to determine which technical considerations contributed to an overall improvement in image quality. RESULTS: After reviewing the data for the 33 subjects, several modified techniques were implemented and parameters were adjusted that enhanced the overall quality of the images. The extremely short half-life of 18F restricts the opportunity to repeat studies that were delayed, interrupted or technically substandard. CONCLUSION: The review of the data indicated that strict adherence to protocol is necessary to achieve optimal results while attempting to incorporate this new imaging modality into a typical nuclear medicine department.     

A portable blood gas analyzer for equine venous blood

Evaluation of a portable blood gas analyzer, (StatPal II, Unifet, Inc, La Jolla, CA) was performed using tonometered solutions and equine blood. Samples were analyzed by the StatPal II and either an Instrument Laboratory IL1306 (Lexington, MA) or a Radiometer ABL50 blood gas analyzer (Radiometer America Inc., Westlake, OH). Comparison of the StatPal II and the IL1306 was done by analysis of 3 tonometered solutions (acidic, normal, and alkalotic) and 27 equine venous blood samples. Blood pH, PCO2, PO2, and [HCO3] values were altered by IV infusion of 5% sodium bicarbonate or exercising the horses on a treadmill. Comparison of the StatPal II and the Radiometer was performed by analysis of 78 blood samples collected from Standardbred horses before a race. Data were analyzed for the venous blood samples using a paired two-tailed Student's t test and Bland-Altman plots, with significance set at P < .05. The coefficients of variation for pH, Pco2, Po2, and [HCO3-] values of the tonometered solutions analyzed by the StatPal II ranged from 0.067% to 0.087%, 2% to 3.21%, 1.21% to 2.67%, and 0.267% to 0.828%, respectively. Comparison of the equine blood samples analyzed by the StatPal II and the IL1306 demonstrated statistically significant, but clinically irrelevant differences in pH, Pco2, and Po2, but not [HCO3-]. There were statistically significant, but clinically irrelevant differences between the StatPal II and the Radiometer for pH, Pco2, and [HCO3-], but not for Po2. It is concluded that the StatPal II provides reproducible and acceptable analysis of equine venous blood gas samples.     

气体体积流量测量中温度和压力修正的必要性

气体流量测量中,温度和压力修正是提高气体流量测量精度的重要手段之一.文中分别介绍温度和压力偏离设定值时对使用直接输出流量计和差压式流量计进行流量测量所带来的误差,并通过工程实例示出温度和压力在8种极端变化状况下产生的测量误差,以对温度和压力变化造成的误差提供一些量的概念.指出,如今实施温度和压力修正并不像以前单元组合仪表那样麻烦,应适当考虑修正.最后给出几点推荐性意见.     

Extracorporeal blood correction in the therapy of drug-resistant mental disorders

544 patients resistant to pharmacotherapy were treated by different methods of extracorporal hemocorrection (EH). Positive changes in mental state were achieved in more than half of the patients by means of EH without any psychopharmacologic drugs. These changes were caused by antipsychotic and antidepressive effects of EH as well as by its ability to normalize biochemical, immunological and rheological blood indices     

Carbohydrate-deficient transferrin values in neonatal and umbilical cord blood

We set out to determine the extent to which two groups of patients reported having been informed about the adverse effects of NSAIDs. These consisted of 50 patients who had suffered an acute gastrointestinal bleed while taking a NSAID, and 100 age, sex and drug matched controls who had not. Eight (16%) of the index patients, and 41 (41%) of the control patients remembered having been informed of potential adverse effects, an odds ratio of 3.65 (95% CI 1.55-8.58, P < 0.002). Two (4%) of the index patients recalled having been advised what to do should adverse symptoms develop, whereas 21 (21%) of the control patients did so, an odds ratio of 6.38 (95% CI 1.4-28.4, P < 0.01). Eighteen (36%) of patients who bled had experienced gastrointestinal pain prior to the bleed, but of these only two (11%) admitted reduced compliance with NSAID therapy. In contrast, 10 (67%) of the 15 control patients who had suffered epigastric discomfort admitted reduced compliance, an odds ratio of 16.0 (95% CI 2.6-98.8, P < 0.001). Our results suggest that patients who report not having been informed of adverse effects of NSAIDs are less likely to reduce intake in response to epigastric pain than patients who report having received such information. If the patients who bled had reduced their intake of NSAIDs to the same extent as apparently better informed control patients in response to epigastric pain, it is possible that some episodes of acute gastrointestinal bleeding would have been avoided.     

Reliability of reporting self-measured blood pressure values by hypertensive patients

For self-measurement of blood pressure to be useful, patient reporting of test results must be reliable and accurate. Until now no study directly measured the accuracy and reliability of patients' reporting of self-measured blood pressure values. Thirty hypertensive patients (69 +/- 11 years) were instructed to measure blood pressure at home over 14 days with the highly accurate Omron IC monitor and to keep a record of all readings in a patient logbook. To assess the reliability of the records, patients were not informed about the memory capacity of the device. We compared automatically stored blood pressure readings with the respective logbook entries to analyze deletion (under-reporting), addition (over-reporting), and precision of reporting of test results. The prevalent pattern was under-reporting, averaging 36% +/- 24% (3% to 89%), which occurred significantly more than over-reporting (9% +/- 11%; 0% to 38%). The precision of reporting (identical values at corresponding times) was 76% +/- 34% (0% to 100%). This observer error did not affect group comparisons of automatically stored values and logbook entries, although the estimated limits of agreement were wide. Blood pressure control, duration of hypertension, age, or previous use of self-measurement and patterns of logbook entries were not found to be predictive of the patients' reliability. Our results demonstrate a substantial observer error in the reporting of self-measured blood pressure values. This bias may be reduced by memory-equipped blood pressure devices.     

Dependency of standardized uptake values of fluorine-18 fluorodeoxyglucose on body size: comparison of body surface area correction and lean body mass correction

In an attempt to minimize dependency of conventional standardized uptake values (SUVs) of F-18-fluorodeoxyglucose (FDG) normalized for the total body weight (TBW) on patient's body weight, the uses of SUV corrected for the lean body mass (LBM) and that corrected for the body surface area (BSA) have been proposed as alternatives. We compared the dependency of SUVLBM and SUVBSA on the overall body size. FDG-PET images were acquired on 44 patients. SUVLBM and SUVBSA for the liver were determined as previously described. Following normalization of the scales of the values obtained from these two approaches, the mean +/- S.D. was 2.86 +/- 0.52 (SUVLBM) and 2.86 +/- 0.50 (SUVBSA). A linear regression analysis was performed for correlating the liver SUVLBM and SUVBSA, with each of TBW, LBM, BSA and height. The dependency of the two values on TBW was similar. SUVLBM showed a moderate dependency on height (r = 0.56, P = 0.00007), LBM (r = 0.55, P = 0.0001) and BSA (r = 0.51, P = 0.0004), whereas SUVBSA showed no dependency on LBM (r = 0.18, P = 0.24) or height (r = 0.20, P = 0.19), and a minimal dependency on BSA (r = 0.38, P = 0.01). In conclusion, SUVBSA appears to be less dependent on overall body size, particularly height and lean body mass, than SUVLBM.     

Temperature distribution of the gas flux in blast furnaces

The distribution of the temperature variation of the gas flux in the peripheral zone over the height (from the bosh to the upper levels of the shaft) and the temperature above the charge surface over the furnace radius was investigated in 2006 at a blast furnace at Metinvest Holding LLC, in various conditions: with gas-free charge and a wet blast; and with natural gas and/or pulverized-coal injection.     

Evaluation of selected publications on reference values for lead in blood

As a part of the global Tracy project, whose aim is to define metal concentrations in tissues and body fluids of reference populations, more than 1000 papers published from 1980 to 1994 were scrutinized that presented tentative reference values for lead in blood in occupationally unexposed adult populations. Ten studies exemplifying criteria for proper sampling, analysis and data treatment are presented and discussed. Levels of lead in blood are influenced by numerous factors. Accordingly, a wide variation in blood lead concentrations was observed. As an example, in a global study in 1983 of nonsmoking female schoolteachers, the geometric mean value for lead in blood varied from 52 micrograms. l-1 in Tokyo, Japan, up to 193 micrograms. l-1 in Mexico City. The Tracy survey demonstrates the importance of factors such as age, gender, ethnicity, food, drinking and smoking habits, hobbies, season and year of sampling, residential area, and geographic location. Lead in blood was shown to be both time and area specific. Thus it was not possible to establish a general reference value for lead in blood.     

Cord blood gas studies: a survey

A 51-year-old black female with sarcoidosis diagnosed 20 yr earlier developed massive chyloperitoneum and chylothorax. Autopsy demonstrated fibrotic and enlarged thoracic and mesenteric lymph nodes. Sarcoidosis can produce chyloperitoneum by producing intrathoracic nodal fibrosis and lymphatic obstruction.