Effect of tracer infusion site on measurement of bicarbonate-carbon dioxide metabolism in dogs

1986 ◽  
Vol 60 (4) ◽  
pp. 1248-1253 ◽  
Author(s):  
R. S. Downey ◽  
A. Mellone ◽  
D. E. Matthews
Keyword(s):  
Carbon Dioxide ◽  
Venous Blood ◽  
Co2 Flux ◽  
Infusion Site ◽  
Peripheral Vein ◽  
Arterial Infusion ◽  
Arterial Blood ◽  
Infusion Study ◽  
Significant Difference ◽  
The Mean

Ten dogs were given a primed infusion of H13CO3- for 220 min while under general anesthesia. Isotopic steady state was reached within 60 min in exhaled CO2, femoral arterial blood HCO3-, and femoral venous blood HCO3-. Halfway through each infusion study, the site of tracer infusion was changed either from the central aorta to a peripheral vein, or vice versa. The mean HCO3(-)-CO2 flux measured from blood HCO3- enrichments was 15.7 +/- 2.1 (SD) mmol X kg-1 X h-1. The mean fraction of tracer recovered in exhaled CO2 was 79 +/- 7% (SD) of the infused dose. No significant difference in either HCO3- flux or recovery of tracer was found between the venous and arterial infusions of tracer. These results indicate that when venous administration of HCO3- tracer is compared with central arterial infusion, the initial loss of tracer into expired CO2 is an unimportant consideration in experiments measuring HCO3- kinetics.

Intrapulmonary Co2 receptors and ventilatory response to lung Co2 loading

1982 ◽  
Vol 52 (5) ◽  
pp. 1272-1277 ◽  
Author(s):  
R. D. Tallman ◽  
F. S. Grodins
Keyword(s):  
Venous Blood ◽  
Co2 Flux ◽  
Minor Role ◽  
Arterial Blood Gas ◽  
Co2 Partial Pressure ◽  
Blood Oxygenator ◽  
Arterial Blood ◽  
Significant Difference ◽  
Pattern Determination ◽  
A Minor

The possible role of intrapulmonary CO2 receptors (IPC) in arterial CO2 partial pressure (PaCO2) homeostasis was investigated by comparing the arterial blood gas and ventilatory responses to CO2 loading via the inspired gas and via the venous blood. Adult male Pekin ducks were decerebrated 1 wk prior to an experiment. Venous CO2 loading was accomplished with a venovenous extracorporeal blood circuit that included a silicone-membrane blood oxygenator. The protocol randomized four states: control (no loading), venous CO2 loading, inspired CO2 loading, and venous CO2 unloading. Intravenous and inspired loading both resulted in hypercapnic hyperpnea. Comparison of the ventilatory sensitivity (delta VE/delta PaCO2) showed no significant difference between the two loading regimes. Likewise, venous CO2 unloading led to a significant hypocapnic hypopnea. Sensitivity to changes in PaCO2 could explain the response of ventilation under these conditions. The ventilatory pattern, however, was differentially sensitive to the route of CO2 loading; inspired CO2 resulted in slower deeper breathing than venous loading. It is concluded that IPC play a minor role in adjusting ventilation to match changes in pulmonary CO2 flux but rather are involved in pattern determination.

Investigation of the Association Between Carotid Artery Intima-Media Thickness (IMT) and Cardiac Risk Factors in Patients with Systemic Lupus Erythematosus

2020 ◽  
Vol 16 (2) ◽  
pp. 125-133
Author(s):  
Zahra Rezaieyazdi ◽  
Sima Sedighi ◽  
Masoumeh Salari ◽  
Mohammadreza H. Fard ◽  
Mahmoud R. Azarpazhooh ◽  
...  
Keyword(s):  
Risk Factors ◽  
Insulin Resistance ◽  
Lupus Erythematosus ◽  
Serum Insulin ◽  
Venous Blood ◽  
Test Group ◽  
Control Groups ◽  
Significant Difference ◽  
The Mean ◽  
And Control

Background: The relationship between SLE and traditional risk factors for cardiovascular events was evaluated. Methods: The data regarding sixty patients with SLE and 30 healthy controls (age and sex matched) were gathered using SLEDAI forms. Venous blood (10mL) from all the participants was examined for hs-CRP, homocysteine, VCAM1, CBC, anti-DNA antibody, C3, C4, low-density lipoprotein (LDL), cholesterol, FBS and triglyceride. : The IMT of carotid arteries was determined bilaterally by ultrasound. Other measurements included insulin levels via Elisa (Linco/Millipore Corp) and the HOMA-IR index for insulin resistance. Results: The mean age (in years) in the test and control groups was 28.8±10.3 (18-52) and 33.8±9.13 (18-48), respectively. Results: The mean age (in years) in the test and control groups was 28.8±10.3 (18-52) and 33.8±9.13 (18-48), respectively. : The average IMT in the test group was directly related to serum levels of VCAM1 (p<0.001), homocysteine (p<0.001), cholesterol (p<0.009), LDL (p<0.001), TG (p<0.001), and FPG (p=0.004). The association between other risk factors, insulin resistance, carotid IMT and SLEDAI, was nonexistent. Mean insulin and insulin resistance levels in all the participants were 0.43±2.06 µU/mL and 0.09±0.44, respectively. There was no significant difference between the test and control groups regarding serum insulin and insulin resistance levels (p=0.42 and p=0.9, respectively). None of the risk factors, such as hsCRP, VCAM1, or homocysteine, were shown to be related to insulin resistance (p=0.6, p=0.6, p=0.09, respectively). Conclusion:: Our findings did not show an increase in the prevalence of atherosclerosis in patients with SLE. There was no association between IMT and insulin resistance. However, the former was associated with FPG, total cholesterol, LDL, TG, homocystein and VCAM1.

Carbon Dioxide Equilibration in Canine Lungs during Rebreathing and Acute Alkalosis

1979 ◽  
Vol 57 (5) ◽  
pp. 385-388 ◽  
Author(s):  
R. D. Latimer ◽  
G. Laszlo
Keyword(s):  
Whole Blood ◽  
Base Excess ◽  
Venous Blood ◽  
Main Pulmonary Artery ◽  
Mixed Venous Blood ◽  
Arterial Blood ◽  
Significant Difference ◽  
Venous Pco2 ◽  
Pulmonary Arterial ◽  
Gas Pressures

1. The left lower lobe of the lungs of six anaesthetized dogs were isolated by the introduction of a bronchial cannula at thoracotomy. Catheters were introduced into the main pulmonary artery and a vein draining the isolated lobe. 2. Blood-gas pressures and pH were measured across the isolated lobe and compared with gas pressures in alveolar samples from the lobe. 3. When the isolated lobe was allowed to reach gaseous equilibrium with pulmonary arterial blood for 30 min, there was no significant difference between alveolar and pulmonary venous Pco2. Mean values of whole-blood base excess were similar in pulmonary arterial and pulmonary venous blood. 4. After injection of 20 ml of 8·4% sodium bicarbonate solution into a peripheral vein, Pco2, pH and plasma bicarbonate concentrations rose in the mixed venous blood. There was no change of whole-blood base excess across the lung, indicating that HCO−3, as distinct from dissolved CO2, did not enter lung tissue in measurable amounts. 5. No systematic alveolar—pulmonary venous Pco2 differences were demonstrated in this preparation other than those explicable by maldistribution of lobar blood flow.

Clinical evaluation of an instrument to measure carbon dioxide tension at the oxygenator gas outlet in cardiopulmonary bypass

Perfusion ◽  
2006 ◽  
Vol 21 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Frode Kristiansen ◽  
Jan Olav Høgetveit ◽  
Thore H Pedersen
Keyword(s):  
Carbon Dioxide ◽  
Cardiopulmonary Bypass ◽  
Venous Blood ◽  
Carbon Dioxide Tension ◽  
Circuit Board ◽  
Separate Analysis ◽  
Blood Gas ◽  
Arterial Blood ◽  
Gas Measurement ◽  
Venous Blood Gas

This paper presents the clinical testing of a new capno-graph designed to measure the carbon dioxide tension at the oxygenator exhaust outlet in cardiopulmonary bypass (CPB). During CPB, there is a need for reliable, accurate and instant estimates of the arterial blood CO2 tension (PaCO2) in the patient. Currently, the standard practice for measuring PaCO2 involves the manual collection of intermittent blood samples, followed by a separate analysis performed by a blood gas analyser. Probes for inline blood gas measurement exist, but they are expensive and, thus, unsuitable for routine use. A well-known method is to measure PexCO2, ie, the partial pressure of CO2 in the exhaust gas output from the oxygenator and use this as an indirect estimate for PaCO2. Based on a commercially available CO2 sensor circuit board, a laminar flow capnograph was developed. A standard sample line with integrated water trap was connected to the oxygenator exhaust port. Fifty patients were divided into six different groups with respect to oxygenator type and temperature range. Both arterial and venous blood gas samples were drawn from the CPB circuit at various temperatures. Alfa-stat corrected pCO2 values were obtained by running a linear regression for each group based on the arterial temperature and then correcting the PexCO2 accordingly. The accuracy of the six groups was found to be (±SD): ±4.3, ±4.8, ±5.7, ±1.0, ±3.7 and ±2.1%. These results suggest that oxygenator exhaust capnography is a simple, inexpensive and reliable method of estimating the PaCO2 in both adult and pediatric patients at all relevant temperatures.

The Significance of the Bohr Effect in the Respiration and Asphyxiation of the Squid, Loligo Pealei

1929 ◽  
Vol 6 (4) ◽  
pp. 340-349 ◽  
Author(s):  
ALFRED C. REDFIELD ◽  
ROBERT GOODKIND
Keyword(s):  
Carbon Dioxide ◽  
Toxic Effect ◽  
Venous Blood ◽  
Bohr Effect ◽  
Reciprocal Effects ◽  
Cent Oxygen ◽  
Carbon Dioxide Content ◽  
Arterial Blood ◽  
Loligo Pealei

1. The oxygen and carbon-dioxide content of the arterial and venous blood of the squid, Loligo pealei, have been measured. 2. Using a nomographic method of analysis it is shown that the reciprocal effects of oxygen and carbon dioxide upon the respiratory properties of squid haemocyanin account for one-third of the respiratory exchange. 3. The venous blood is estimated to be 0.13 pH unit more acid than the arterial blood. 4. Death from asphyxiation occurs when the oxygen and carbon-dioxide pressures are such that the arterial blood can combine with only 0.5 to 1.5 volumes per cent, oxygen. Carbon dioxide exerts no toxic effect except through its influence on the oxygenation of the blood. 5. The haemocyanin of the blood is of vital necessity to the squid, because the amount of oxygen which can be physically dissolved in blood is less than the amount which is necessary for the maintenance of life.

Feasıbılıty of Transcutaneous Method for Carbon Dıoxıde Monıtorıng in an Intensive Care Unıt

2022 ◽  
Vol 18 ◽  
Author(s):  
Nazlıhan Boyacı ◽  
Sariyya Mammadova ◽  
Nurgül Naurizbay ◽  
Merve Güleryüz ◽  
Kamil İnci ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Intensive Care Unit ◽  
Intensive Care ◽  
Partial Pressure ◽  
Blood Gas ◽  
Peripheral Oxygen Saturation ◽  
Arterial Blood Gas ◽  
Arterial Blood ◽  
Randomized Controlled Studies ◽  
Significant Difference

Background: Transcutaneous partial pressure of carbon dioxide (PtCO2) monitorization provides a continuous and non-invasive measurement of partial pressure of carbon dioxide (pCO2). In addition, peripheral oxygen saturation (SpO2) can also be measured and followed by this method. However, data regarding the correlation between PtCO2 and arterial pCO2 (PaCO2) measurements acquired from peripheric arterial blood gas is controversial. Objective: We aimed to determine the reliability of PtCO2 with PaCO2 based on its advantages, like non-invasiveness and continuous applicability. Methods: Thirty-five adult patients with hypercapnic respiratory failure admitted to our tertiary medical intensive care unit (ICU) were included. Then we compared PtCO2 and PaCO2 and both SpO2 measurements simultaneously. Thirty measurements from the deltoid zone and 26 measurements from the cheek zone were applied. Results: PtCO2 could not be measured from the deltoid region in 5 (14%) patients. SpO2 and pulse rate could not be detected at 8 (26.7%) of the deltoid zone measurements. Correlation coefficients between PtCO2 and PaCO2 from deltoid and the cheek region were r: 0,915 and r: 0,946 (p = 0,0001). In comparison with the Bland-Altman test, difference in deltoid measurements was -1,38 ± 1,18 mmHg (p = 0.252) and in cheek measurements it was -5,12 ± 0,92 mmHg (p = 0,0001). There was no statistically significant difference between SpO2 measurements in each region. Conclusion: Our results suggest that PtCO2 and SpO2 measurements from the deltoid region are reliable compared to the arterial blood gas analysis in hypercapnic ICU patients. More randomized controlled studies investigating the effects of different measurement areas, hemodynamic parameters, and hemoglobin levels are needed.

scholarly journals Vitamin D Status among Young Children Aged 6 to 23 Months from 4 Different Ethnic Groups in Yunnan, China

2018 ◽  
Vol 39 (2) ◽  
pp. 260-265
Author(s):  
Yanhong Li ◽  
Yan Li ◽  
Xian Zhang ◽  
Lin Zhao ◽  
Liqin Chen ◽  
...  
Keyword(s):  
Vitamin D ◽  
Young Children ◽  
Vitamin D Deficiency ◽  
Ethnic Groups ◽  
Venous Blood ◽  
Hydroxyvitamin D ◽  
Significant Difference ◽  
25 Hydroxyvitamin D ◽  
The Mean ◽  
Venous Blood Sampling

Objectives: To determine the prevalence of vitamin D deficiency in 6- to 23-month-old children from 4 different ethnic groups, Han, Lisu, Hani, and Bai, in Yunnan Province of China. Methods: A large cohort of 938 young children aged 6 to 23 months who were living in Yunnan, China (23°28′-27°52′ N), were selected and recruited in this study. Venous-blood sampling was conducted in all the participants, and serum 25-hydroxyvitamin D [25(OH)D] levels were measured. The children’s physical status was measured. Results: General mean serum 25(OH)D level was 21.46 ± 7.95 ng/mL, which was obtained from a total of 938 cases. No significant difference was found in age, gender, height, and weight of participants from different ethnic groups. The mean 25(OH)D level was significantly lower in children of Lisu ethnic groups compared with that of Han and Hani participants, respectively ( P < .05). In addition, Bai children had lower 25(OH)D content than Hani children ( P < .001). Among the children with 25(OH)D sufficiency, the number of Lisu participants was significantly lower than Han children ( P < .001). Conclusion: The prevalence of vitamin D deficiency varied among the ethnically different children in Yunnan, China, and significantly fewer Lisu children maintained vitamin D sufficiency compared with other ethnic children. Recognizing these ethnic differences in treating children with vitamin D deficiency may improve the therapeutic outcome.

scholarly journals Comparison of Lipid Profile in Type-2 Obese Diabetics and Obese Non-diabetic Individuals. A hospital Based Study from Western Nepal

2013 ◽  
Vol 10 (3) ◽  
pp. 44-47 ◽  
Author(s):  
Naval Kishor Yadav ◽  
C Thanpari ◽  
MK Shrewastwa ◽  
RK Mittal
Keyword(s):  
Lipid Profile ◽  
Venous Blood ◽  
Diabetic Patients ◽  
Type 2 Diabetic Patients ◽  
Serum Triglycerides ◽  
Control Subjects ◽  
Significant Difference ◽  
The Mean ◽  
Type 2 Diabetic

Background Type-2 diabetes mellitus is an independent risk factor for coronary artery disease and risk of coronary disease is three to four fold increased in patients with diabetes compared with non-diabetic population and 60-80% 0f type-2 diabetics are obese. Methods This study was conducted in Nepalgunj Teaching Hospital, Kohalpur, Banke, Nepal, between 1st March, 2011 and 28th February, 2012. A total of 150 samples were taken to assess the lipid profile in type-2 diabetic patients associated with obesity and 25 obese controls for their lipid profile. Venous blood samples were taken from all the subjects in the morning after fasting overnight. Exclusion criteria included pregnancy, chronic infectious disease, heart failure; renal failure and drug allergy were confirmed from the subject’s personal physician report and a detailed history. The data was analyzed using Excel 2003, R 2.8.0 Statistical Package for the Social Sciences (SPSS) for Windows Version 16.0 (SPSS Inc; Chicago, IL, USA) and the EPI Info 3.5.1 Windows Version. Results The mean ± SD age of diabetic patients with obesity was 53.76 ± 6.23 while the mean ± SD age of control was 49.61 ± 4.8. Out of 150 patients 105 (70%) were males and 45 (30%) were females. Among control subjects 16 (64%) were males and 9 (36%) were females. Obese type-2 diabetic patients when compared to obese control subjects showed statistically significant increase in the levels of serum total cholesterol (p ? 0.001), serum triglycerides (p ? 0.001), serum LDL-cholesterol (p ? 0.001) while serum HDL-cholesterol levels did not show statistically significant difference in the two group (p ? 0.05). Conclusion This study showed obese diabetic individuals have dyslipidemia and more prone to develop cardiovascular diseases. Kathmandu University Medical Journal | VOL.10 | NO. 3 | ISSUE 39 | JUL- SEP 2012 | Page 44-47 DOI: http://dx.doi.org/10.3126/kumj.v10i3.8017

scholarly journals The irreversible loss of alanine and of glycine in fetal and sucking lambs

1984 ◽  
Vol 52 (3) ◽  
pp. 529-543 ◽  
Author(s):  
G. M. Hatfield ◽  
Jenny Joyce ◽  
Marjorie K. Jeacock ◽  
D. A. L. Shepherd
Keyword(s):  
Specific Activity ◽  
Single Injection ◽  
Venous Blood ◽  
Injection Technique ◽  
Irreversible Loss ◽  
Fetal Tissues ◽  
Arterial Blood ◽  
Pool Model ◽  
The Mean ◽  
Mean Concentration

1. Estimates have been made of the irreversible loss of alanine and of glycine in chronically catheterized fetal lambs and in sucking lambs using [U-14C]-labelled radioisotopes. The experiments in the fetal lambs were carried out at least 5 d after implantation of catheters.2. The mean concentration of glycine in fetal femoral arterial blood between 102 and 129 d conceptual age was 755 μmol/l and this was not significantly different from that in maternal venous blood. The mean concentration of alanine in fetal femoral arterial blood during the same period of gestation was 229μmol/l and this was significantly greater than that in maternal venous blood.3. Assuming a catenary model, the mean irreversible loss of glycine, determined using the single-injection technique, in three fetal lambs of 107, 111 and 127 d conceptual age was 17 μmol/min per kg, whereas in two fetal lambs aged 106 and 109 d into which the isotope was infused continuously the mean irreversible loss, calculated from the specific activity of glycine 5 h after the start of infusion of the tracer ('pseudo plateau'), was 12 μmol/min per kg. In a sucking lamb, 9 d after birth, the irreversible loss of glycine was 11 μmol/min per kg. The mean irreversible loss of alanine, determined by the single-injection technique assuming a catenary model in five fetuses between 112 and 121 d conceptual age was 14μmol/min per kg, and in two sucking lambs, 9 and 11 d after birth, it was 5.1 μmol/min per kg.4. When a two-pool model was assumed in which entry of metabolite was not directly into the sampling pool but was by way of the second pool, then the mean irreversible loss of glycine in the three fetuses was 23 μmol/min per kg and of alanine in the five fetuses was 32 μmol/min per kg. Calculations based on the alternative two-pool model did not alter appreciably the rates of irreversible loss of either alanine or glycine in the sucking lambs.5. From a comparison of the specific activities of the amino acids and of carbon dioxide in blood during the course of the experiments, it was found that in the fetuses 0.96% of the CO2 present in blood was derived from alanine and only 0.12% was derived from glycine. It was calculated that not more than 1.6 μmol lanine/min per kg and 0.29 μmol glycine/min per kg could have been converted to CO2 in the fetal lambs.6. It is concluded that since glycine in fetal blood originates from fetal tissues and not from direct transfer across the placenta the upper value for the irreversible loss describes metabolism best. In the case of alanine, which is derived from both the maternal circulation and from metabolism in fetal tissues, the true rate of irreversible loss must lie between the values predicted by the two models.

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