OBJECTIVETo establish a method for simultaneous determination of 17 common pesticides in whole blood by solid phase extraction-gas chromatography-mass spectrometry (SPE-GC-MS).

METHODSWhole blood samples were treated by extraction with acetonitrile, and the obtained extract was cleaned up using an Oasis HLB SPE cartridge; pesticides were separated by GC and quantitatively analyzed by MS with selected ion monitoring.

RESULTSThe concentrations of 17 pesticides in whole blood were 1.0-5.0 mg/L, and the recovery rate was 41.3-102.1%, with a relative standard deviation of less than 10%in most pesticides. The 17 pesticides showed a good linear relationship between concentration and peak area within 0.5-5.0 mg/L, with a correlation coefficient of 0.9945-0.9994. The limit of detection and limit of quantification were 0.02-0.05 mg/L and 0.05-0.09 mg/L, respectively.

CONCLUSIONWith this method, 17 pesticides in whole blood can be well separated and determined. This method has high sensitivity, accuracy, and precision and can be used for identification and quantification of multiple pesticides in blood samples.

Blood Chemical Analysis ; methods ; Chromatography, Liquid ; methods ; Gas Chromatography-Mass Spectrometry ; methods ; Humans ; Pesticides ; blood

The main purpose of this paper is to describe the design and development of the near-infrared blood-oxygen monitor which is based on the theory of detecting the blood-oxygen parameters of tissue by near-infrared, and the monitor can detect the blood-oxygen parameters of two sides of the local brain tissue. The monitor uses two wavelength ultra-high light LED as lamp-house, and two sensors detect the light scattered by two sides of the local brain tissue, which make the monitor achieve the function of dual detector. The appearance of the monitor's detector is designed to reduce effectively the noise brought by the background and alleviate the discomfort feelings of the patient. At the same time, this apparatus can monitor continuously the brain blood-oxygen parameters of the patients in real time, and output the curves of the blood-oxygen and oxygen concentration of two sides of brain tissue. At last, the biological model experiments and the tests in clinical setting validate the monitor.
Blood Gas Analysis ; instrumentation ; methods ; Brain ; blood supply ; Humans ; Monitoring, Physiologic ; instrumentation ; Oximetry ; instrumentation ; methods ; Oxygen ; blood ; Spectroscopy, Near-Infrared

OBJECTIVESince 2011 EB-APS conference, we hypotheses that phase switching of inspiration-expiration is dominantly initiated by oscillatory information PaO2, PaCO2 and [H+] via fast peripheral chemical receptors. However, the evidence of the waveform of ABG is lack.

METHODSSix surgery patients with normal heart function and negative Allen test, had been placed the arterial catheterization directly connected to 3 x 1 000 mm pre-heparin plastic pipe for continuous collecting arterial blood. We counted the number of heart beat for the blood collecting time, and separated the blood pipe into the heart beat numbers' short pieces using haemostatic forceps, then put pipe into iced water at once fir analyzing PaO2, PaCO2, pH and SaO2 as soon as possible. We selected two breaths cycles of waveform from each patient for data calculations of magnitudes and time interval.

RESULTSThe heart beat numbers for filling blood into pipe were 16 ± 2, and all covered more than 2 breathing cycles. Each breathing cycle is cover 5 ± 0.6 heart beat. There were significant changes of PaO2, PaCO2, [H+] a and SaO2 (i.e. the highest high values compare to the next lowest values, P < 0.05). The time interval of changing PaO2, PaCO2, [H+]a and SaO2 magnitudes were 11.28 ± 1.13 mmHg, 1.77 ± 0.89 mmHg, 1.14 ± 0.35 nmol/L and 0.52% ± 0.44% respectively.

CONCLUSIONThis simple continuous beat-by-beat arterial blood sampling and ABG analyzing method is new and practicable. We obtain a clear evidence of periodic parameters ABG waveform, which following breathing cycle.

Arteries ; physiology ; Blood Gas Analysis ; Heart Rate ; Humans ; Monitoring, Physiologic ; methods ; Respiration

High oxygen-affinity hemoglobin (Hb) variants and a 2,3-diphosphoglycerate (2,3-DPG) deficiency could cause congenital (familial) erythrocytosis. High oxygen-affinity Hb variants and a 2,3-DPG deficiency might result in low tissue oxygen tension left-shifted oxygen dissociation curves and reduction in the standard P₅₀ value (P(50,std), oxygen tension at which haemoglobin is 50% saturated). Hence, the P(50,std) value is considered while formulating diagnostic strategies for erythrocytosis. In this study, we established a reference range for P(50,std) using an International Federation of Clinical Chemistry and Laboratory Medicine-approved equation (Hill's equation) for individual single venous/arterial blood samples. Blood gas analysis results of 243 samples with oxygen saturation ranging from 40%–90% (Hb < 16 mg/dL) were selected. The reference range of P(50,std) was in the 2.5th–97.5th percentile, and was 25.9–27.3 mm Hg. Hill's equation is a simple approved method for evaluating the P(50,std) values. Only a single sample of venous or arterial blood and a blood gas analyser are required to obtain the P(50,std). Our study provides a useful tool for the diagnostic work-up of patients with erythrocytosis.
2,3-Diphosphoglycerate ; Blood Gas Analysis ; Chemistry, Clinical ; Humans ; Methods ; Oxygen ; Polycythemia* ; Reference Values

BACKGROUND: Point-of-care (POC) arterial blood gas analysis (ABGA) is widely used for checking hemoglobin (Hb) level. However, there is the tendency of downward bias of conductivity-based POC ABGA Hb measurement compared with optical methods. Authors tried to correct that bias by linear regression equation. METHODS: We retrospectively collected a total of 86 Hb result pairs during surgeries. Hb measured by the Sysmex XE-2100 in the laboratory was set as the gold standard and was compared with that measured by the GEM Premier 3500. Data were compared using the Bland-Altman analysis, the reliability of transfusion decision was assessed using three-zone error grid. The linear regression analysis was performed to find out the relation between the Hb results of POC ABGA and those of laboratory based test. RESULTS: The bias of the Hb measured between Sysmex XE-2100 and GEM Premier 3500 was −0.9 g/dl (P < 0.001, 95% confidence interval, −1.038 to −0.665 g/dl). The percentage error was 16.4%. According to error grid methodology, zone A, B and C encompassed 89.5%, 10.5% and 0% of data pairs. After adjusting the POC ABGA Hb values, the bias of the Hb measured by two methods was 0 g/dl (P = 0.991). The percentage error was 18.2%. The zone A, B and C encompassed 91.9%, 8.1% and 0% of data pairs. CONCLUSIONS: Hb measurements obtained with reference to conductivity via a POC ABGA were significantly lower than those obtained via optical methods. This bias may deserve attention of anesthesiologists when POC ABGA Hb level is used as a transfusion guideline.
Bias (Epidemiology)* ; Blood Gas Analysis ; Linear Models ; Methods* ; Point-of-Care Systems* ; Point-of-Care Testing ; Retrospective Studies

Adult ; Aged ; Ascitic Fluid ; chemistry ; Blood Gas Analysis ; methods ; Carbon Dioxide ; analysis ; blood ; Female ; Humans ; Hydrogen-Ion Concentration ; Liver Cirrhosis ; blood ; Male ; Middle Aged ; Oxygen ; analysis ; blood

OBJECTIVETo measure the range of plasma hydrogen sulfide (H2S) in children.

METHODSTotally 200 healthy children were classified into 4 groups based on age and sex: 7-14 years old group (n = 75, 43 boys and 32 girls), 15-19 years old group (n = 125, 64 boys and 61 girls). Plasma H2S level was detected by a modified sulfide electrode-based method.

RESULTSPlasma H2 S levels were (52.2181 +/- 17.9400) micromol/L in 7-14 years old boys, (51.9441 +/- 16.5448) micromol/L in 7-14 years old girls, (52.8771 +/- 14.1444) micromol/L in 15-19 years old boys, and (53.6551 +/- 14.5563) micromol/L in 15-19 years old girls (P > 0.05). In summary, the range of plasma H2S in children was about (52.8234 +/- 15.4339) micromol/L.

CONCLUSIONThe range of plasma H2S in children is about (52.8234 +/- 15.4339) micromol/L.

Adolescent ; Age Factors ; Blood Gas Analysis ; methods ; Child ; Female ; Humans ; Hydrogen Sulfide ; blood ; Male ; Reference Values ; Sex Factors

OBJECTIVETo establish an animal model of non-transthoracic cardiopulmonary bypass (CPB) in rats.

METHODSTen adult male Sprague-Dawley rats, weighing 350-500 g, were used in this study. CPB was established in these animals through cannulating the left carotid and right jugular vein for arterial perfusion and venous return. The components of perfusion circuit, especially the miniature oxygenator and cannula, were specially designed and improved. The mean arterial pressure was measured with a blood pressure meter through cannulating the left femoral artery. The hemodynamic and blood gas parameters were also monitored.

RESULTSThe rat model of non-transthoracic CPB was established successfully. The hemodynamical parameters were changed within an acceptable region during CPB. The miniature oxygenator was sufficient to meet the standard of satisfactory CPB.

CONCLUSIONSThe rat model of non-transthoracic CPB established through the carotid and jugular cannulation is feasible, easily operated, safe, reliable, and economic. It is an ideal model for the pathophysiological research of CPB.

Animals ; Blood Gas Analysis ; Blood Pressure ; Cardiopulmonary Bypass ; methods ; Disease Models, Animal ; Heart Rate ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo compare cricothyroid membrane puncture directed tracheostomy (CMPDT) with conventional surgical tracheostomy (ST) and cricothyroidotomy (CT) and to evaluate the feasibility, efficacy and safety of this novel technique.

METHODS15 minipigs were divided randomly into 3 groups, 5 in each. After general anesthesia, CMPDT, ST and CT were performed respectively according to the established techniques when SPO₂reached 80% (T0). Procedure duration, ECG and arterial blood gas results were recorded. Complications were recorded and scored according to an established score scale by an observer blinded to the grouping.

RESULTSAirway was successfully established in all animals (15/15). ECG monitor showed T-wave decreased and Q-T shortened after seasing of oxygen supply and both recovered rapidly to normal levels after reoxygenation. There were no significant differences between 3 groups in HR, BP, SPO2, SaO₂, PaO₂, PaCO₂and pH at pre-apnea, T0 or post-operation, but with significant intragroup variation in the parameters before and after operation. The time for CMPDT, ST and CT was (174 ± 34) s, (619 ± 128) s and (86 ± 12) s respectively. Three of 5 minipigs in ST group experienced hypotension due to longer time of hypoxia. 1 and one had minor bleeding and stoma infection after surgery. One of 5 animals in CT group had minor laryngeal cartilage injury leading to difficult decannulation, postoperative fiber bronchoscopy showed no subglottic stenosis. The complication scores were 13, 9, and 3 for ST, CT and CMPDT, respectively.

CONCLUSIONSAll 3 methods can provide with effective airway access with no significant differences in ventilation effect, however CMPDT has short recovery time for SpO2 and other vital signs with the lowest complication score. The animal experiment suggests that CMPDT is a fast, safe and effective surgical technique for emergency airway.

Anesthesia, General ; Animals ; Blood Gas Analysis ; Bronchoscopy ; Emergency Treatment ; methods ; Hypoxia ; Larynx ; surgery ; Swine ; Swine, Miniature ; Tracheostomy ; methods

OBJECTIVE: To focus on the main factors that may influence the stability of ethanol in blood then try to establish the best conditions for preserving ethanol in blood. METHODS: Four crucial parameters, including temperature (-20, 4, 20 degrees C), preservative (NaF, No preservative, Na2O2), percentage of air chamber in container (0%, 25%, 50%), and ethanol concentration in blood (0.2, 0.8, 2.0 mg/mL) were investigated. Blood samples were stored under different conditions designed by orthogonal design L, (3(4))method. Quantification of ethanol in blood was carried out by headspace gas chromatography with FID detector. The results were statistically evaluated by analysis of variance. RESULT: Significant changes of ethanol concentrations were observed in the samples stored in 20 degrees C without any reserveative, while there were no obvious changes in the samples under other storage conditions. CONCLUSION The best condition for keeping ethanol in blood stable is 4 degrees C with preservative and with 50% of air chamber in container. The temperature is main effective factor in the four factors.
Air ; Analysis of Variance ; Blood Preservation ; Chromatography, Gas ; Ethanol/chemistry* ; Forensic Medicine/methods* ; Humans ; Specimen Handling/methods* ; Temperature ; Time Factors