Recent blood gas analysis as emergency testing

Laboratory specimen tests, histological exams, physiological tests and image diagnoses are routinely conducted on medical premises. These include emergency specimen testing such as hematological exams, partial biochemical exams and partial immunology exams. Emergency tests, especially those carried out by doctors and nurses in the operating theatre, nurse's station and bedside are called Point Of Care Tests or Near Patient Tests. The purpose is to facilitate quick, accurate diagnosis, thereby increasing the effectiveness of critical care. POCT/NPT was started due to an increasing requirement in the USA for faster turnaround times, and made possible with the development of high quality portable medical devices with sensor technology. In this article, the history and most recent information, diagnosis and treatment using Blood Gas Analysis, a mandatory test for critically ill patients, is described.     

Smoking induced changes in EEG two-dimensional maps and blood gas analysis

Summary The effects of smoking on mental function were investigated by the two-dimensional EEG mapping method, and the results were analyzed in conjunction with blood gas data that had been obtained simultaneously. Healthy medical students from the National Defense Medical College were used as the subjects for this experiment. They live in the same dormitory and a similar lifestyle to regular military personnel. Tests were carried out on two successive days, and in between the two testing sessions, each subject was requested to refrain from smoking for 24 hours. During the testing sessions, EEGs were recorded with eyes closed, before and after smoking. Two-dimensional maps were generated by unbiased polynomial interpolation for alpha activity. Various blood chemical measurements were made, among which, partial pressure of carbon dioxide (pCO₂) and percentage of carbon monoxide hemoglobin (%COHb) were studied in relation to EEG changes. The smoking induced wide-spread amplitude decrease in the alpha maps. After 24 hours of withdrawal, alpha amplitude increased, although it decreased again when smoking resumed. Either the correlation between EEG amplitude and %COHb, or the correlation between EEG amplitude and pCO₂, was examined in three regions (anterior: A, middle: M and posterior: P) of the two-dimensional maps in both slow and quick smokers. There were no correlations observed between changes in the EEG amplitude and changes in %COHb induced by smoking, in any of the three regions in either fast or slow smokers. However, there was a clear correlation between changes in the EEG amplitude and changes in pCO₂ in quick smokers, the correlation coefficient being approximately -0.7. It is possible that this relationship was due to hyperventilation, since the same tendency was not observed in slow smokers.This work was supported by a grant from the Smoking Research Center.     

Air bubbles and temperature effect on blood gas analysis.

The effect of temperature, time of storage, and presence of air bubbles in specimens for blood gas analysis was studied. The results show that air bubbles in a 10% proportion are undesirable because of significant elevation in the PO2, and the storage of anaerobic blood samples at room temperature (25 degrees C) is acceptable when measurements are done within the first 20 minutes.     

Point care testing in blood gas and electrolyte analysis : examples of implementation and cost analysis

An increasing proportion of laboratories manage and organize point of care testing (POCT). The purpose of this article is to describe the implementation made at Lariboisière hospital for three remote blood gas analysers. The most important aspect in this achievement is the comprehensive computerization, making possible real time management of POCT in agreement with the Point of Care unit Management team. In addition, we present a running cost analysis, comparing three Blood gas systems (Rapidlab860, Rapidpoint 400--Bayer Diagnostics and i-Stat Abbott Diagnostics). This study indicates that cost per test hugely varies based on the daily sample demand. In addition to analytical and organizational items, the clinical chemist should consider the testing demand as a key factor in choosing an analyser for POCT.     

脐带血免疫学特性的研究进展

脐带血干/祖细胞移植在造血和免疫系统的恢复与重建中具有重要的临床应用前景.脐带血中含有丰富的造血和免疫活性物质,脐带血免疫细胞的功能特性与脐带血细胞的成功移植和低GVHD的发生密切相关.此外,脐带血的单核细胞、树突状细胞和NK细胞还在血液系统及其他肿瘤的免疫治疗中有研究价值.     

超声图像血管分割的研究进展

主要阐述超声图像血管分割算法及其评价指标。基于特征提取的经典图像处理算法不能摆脱对人工的依赖,削弱了分割算法的泛化能力;但对于缺乏大样本超声血管图像的研究场景下,充分利用传统且成熟的技术方法却是一种可行的研究办法。基于机器学习的算法提高了分割算法的泛化能力,改善了传统方法的短板;但深度学习技术对数据的依赖性强、可解释性差,其算法的有效性、稳定性还需深入研究。血管分割评价算法的研究极其重要,研究适合超声图像血管分割的客观评价方法也是重要课题之一。总之,传统方法仍然是解决超声图像血管分割的有效方法,传统方法与深度学习技术的紧密结合是未来的发展趋势。     

Enlarged acid-base and blood gas calculations by electronical data computing in the blood gas laboratory.

A rapid anaysis of parameters of the acid-base equilibrium and blood gases during open heart surgery and emergency therapy is absolutely necessary. Computing of the several parameters of the acid-base status by slide rules or nomograms is time consuming and can be shortened by computer applications. The central blood gas laboratory consists of a blood gas analyzer for PO2, PCO2 and pH, an electronic desktop calculator, a four color X-Y-plotter and two data lines to the cardiac surgery unit and to the intensive care unit. The time needed for computing and feedback of the parameters could be decreased to one quarter. In addition to numerical data printout, a graphical representation of the several parameters is possible on a X-Y-plotter and includes the Rahn-Fenn-O2-CO2-Diagram with venous admixture, ventilation perfusion ratio, alveolar dead space ventilation and the standard and actual oxygen dissociation curve as well as the pH/HCO3- Acid-Base nomogram. Furthermore, a computer diagnosis of the actual disturbances can be plotted.     

Interpretation of arterial blood gas

Disorders of acid–base balance can lead to severe complications in many disease states, and occasionally the abnormality may be so severe as to become a life-threatening risk factor. The process of analysis and monitoring of arterial blood gas (ABG) is an essential part of diagnosing and managing the oxygenation status and acid–base balance of the high-risk patients, as well as in the care of critically ill patients in the Intensive Care Unit. Since both areas manifest sudden and life-threatening changes in all the systems concerned, a thorough understanding of acid–base balance is mandatory for any physician, and the anesthesiologist is no exception. However, the understanding of ABGs and their interpretation can sometimes be very confusing and also an arduous task. Many methods do exist in literature to guide the interpretation of the ABGs. The discussion in this article does not include all those methods, such as analysis of base excess or Stewart’s strong ion difference, but a logical and systematic approach is presented to enable us to make a much easier interpretation through them. The proper application of the concepts of acid–base balance will help the healthcare provider not only to follow the progress of a patient, but also to evaluate the effectiveness of care being provided.