GAS EXCHANGES AND BLOOD GAS CONCENTRATIONS IN THE FORG RANA RIDIBUNDA

1974 ◽  
Vol 60 (3) ◽  
pp. 901-908
Author(s):  
M. G. EMíLIO
Keyword(s):  
Carbon Dioxide ◽  
Partial Pressure ◽  
Ph Value ◽  
Total Concentration ◽  
Blood Gas ◽  
Gas Exchanges ◽  
Arterial Blood ◽  
Low Levels ◽  
Time Courses ◽  
Metabolic Carbon

1. The respiratory exchanges through the lungs and skin of frogs and the time courses of blood gas concentrations were studied during emergence and diving periods. 2. Most of the total oxygen uptake is carried out through the lungs. The partial pressure of oxygen in arterial blood falls to very low levels a few minutes after diving, showing that the cutaneous respiratory surface cannot compensate for the lack of lung respiration. 3. Most of the metabolic carbon dioxide is disposed of through the skin. Although the skin output is maintained through diving periods, there is an important rise in the partial pressure of carbon dioxide in blood following submergence. However, the total concentration of CO2 in the blood decreases, as does the blood pH value. 4. This phenomenon is probably the result of a metabolic acidosis due to the switching on of anaerobic processes during diving periods.

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.

Maternal Insufflation during the Second Trimester Equivalent Produces Hypercapnia, Acidosis, and Prolonged Hypoxia in Fetal Sheep

2004 ◽  
Vol 101 (6) ◽  
pp. 1332-1338 ◽  
Author(s):  
Kenichiro Uemura ◽  
Rebecca J. McClaine ◽  
Sebastian G. de la Fuente ◽  
Roberto J. Manson ◽  
Kurt A. Campbell ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Blood Flow ◽  
Oxygen Saturation ◽  
Partial Pressure ◽  
Uterine Blood Flow ◽  
Second Trimester ◽  
Blood Gas ◽  
Fetal Sheep ◽  
Total N ◽  
Arterial Blood

Background Anecdotal reports suggest that the second trimester is the safest time to conduct a laparoscopic procedure on a pregnant patient, but this supposition has not been tested empirically. Methods Previously instrumented preterm sheep (total n = 8) at gestational day 90 (term, 145 days) were anesthetized and then insufflated with carbon dioxide for 60 min at a pressure of 15 mmHg. Cardiovascular parameters were continuously recorded while blood gas status was determined before and at 15-min intervals during and up to 2 h after insufflation. Results Insufflation produced minimal maternal blood gas or cardiovascular changes except for a significant reduction in uterine blood flow. The decrease in perfusion increased fetal arterial blood partial pressure of carbon dioxide and decreased fetal pH, oxygen saturation, and oxygen content; there was also progressive fetal hypotension and bradycardia. After manually deflating the ewe, uterine blood flow returned to normal, and the fetal partial pressure of carbon dioxide and pH changes resolved within 1 h. However, fetal oxygen saturation and content remained depressed, and fetal cardiovascular status continued to decline during the 2-h postinsufflation monitoring period. Conclusion Previous studies with near-term sheep determined that carbon dioxide pneumoperitoneum produces respiratory acidosis but does not decrease fetal oxygenation. In contrast, the current findings indicate that in the preterm fetus, insufflation-induced hypercapnia and acidosis are accompanied by prolonged fetal hypoxia and cardiovascular depression. This result suggests that additional work should be conducted to confirm the presumed safety of conducting minimally invasive procedures during the second trimester.

Atrial fibrillation associated with carbon monoxide poisoning

2019 ◽  
pp. 203-206
Author(s):  
Mevlut Demir ◽  
◽  
Muslum Sahin ◽  
Ahmet Korkmaz ◽  
◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Carbon Monoxide ◽  
Sinus Rhythm ◽  
Partial Pressure ◽  
Motor Vehicle ◽  
Carbon Monoxide Poisoning ◽  
Venous Blood ◽  
Blood Gas ◽  
Arterial Blood Gas ◽  
Arterial Blood

Carbon monoxide intoxication occurs usually via inhalation of carbon monoxide that is emitted as a result of a fire, furnace, space heater, generator, motor vehicle. A 37-year-old male patient was admitted to the emergency department at about 5:00 a.m., with complaints of nausea, vomiting and headache. He was accompanied by his wife and children. His venous blood gas measures were: pH was 7.29, partial pressure of carbon dioxide (pCO2) was 42 mmHg, partial pressure of oxygen (pO2) was 28 mmHg, carboxyhemoglobin (COHb) was 12.7% (reference interval: 0.5%-2.5%) and oxygen saturation was 52.4%. Electrocardiogram (ECG) examination showed that the patient was not in sinus rhythm but had atrial fibrillation. After three hours the laboratory examination was repeated: Troponin was 1.2 pg/ml and in the arterial blood gas COHb was 3%. The examination of the findings on the monitor showed that the sinus rhythm was re-established. The repeated ECG examination confirmed the conversion to the sinus rhythm. He was monitored with the normobaric oxygen administration.

scholarly journals Analysis of Arterial Blood Gas Values Based on Storage Time Since Sampling: An Observational Study

2021 ◽  
Vol 11 (3) ◽  
pp. 517-521
Author(s):  
Alejandro Montero-Salinas ◽  
Marta Pérez-Ramos ◽  
Fernando Toba-Alonso ◽  
Leticia Quintana-DelRío ◽  
Jorge Suanzes-Hernández ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Observational Study ◽  
Partial Pressure ◽  
Group Analysis ◽  
Initial Time ◽  
Blood Gas ◽  
Initial Sample ◽  
Arterial Blood Gas ◽  
Arterial Blood ◽  
Prospective Longitudinal

Aim. To evaluate the influence of time on arterial blood gas values after artery puncture is performed. Method. Prospective longitudinal observational study carried out with gasometric samples from 86 patients, taken at different time intervals (0 (T0), 15 (T15), 30 (T30) and 60 (T60) min), from 21 October 2019 to 21 October 2020. The study variables were: partial pressure of carbon dioxide, bicarbonate, hematocrit, hemoglobin, potassium, lactic acid, pH, partial pressure of oxygen, saturation of oxygen, sodium and glucose. Results. The initial sample consisted of a total of 90 patients. Out of all the participants, four were discarded as they did not understand the purpose of the study; therefore, the total number of participants was 86, 51% of whom were men aged 72.59 on average (SD: 16.23). In the intra-group analysis, differences in PCO2, HCO3, hematocrit, Hb, K+ and and lactic acid were observed between the initial time of the test and the 15, 30 and 60 min intervals. In addition, changes in pH, pO2, SO2, Na and glucose were noted 30 min after the initial sample had been taken. Conclusions. The variation in the values, despite being significant, has no clinical relevance. Consequently, the recommendation continues to be the analysis of the GSA at the earliest point to ensure the highest reliability of the data and to provide the patient with the most appropriate treatment based on those results.

Validation of transcutaneous carbon dioxide monitoring using an artificial lung during adult pulsatile cardiopulmonary bypass

2021 ◽  
pp. 039139882098785
Author(s):  
Lawrence Garrison ◽  
Jeffrey B Riley ◽  
Steve Wysocki ◽  
Jennifer Souai ◽  
Hali Julick
Keyword(s):  
Carbon Dioxide ◽  
Cardiopulmonary Bypass ◽  
Gold Standard ◽  
Blood Gas Analysis ◽  
Gas Analysis ◽  
Artificial Lung ◽  
Blood Gas ◽  
Median Difference ◽  
Transcutaneous Carbon Dioxide ◽  
Arterial Blood

Measurements of transcutaneous carbon dioxide (tcCO2) have been used in multiple venues, such as during procedures utilizing jet ventilation, hyperbaric oxygen therapy, as well as both the adult and neo-natal ICUs. However, tcCO2 measurements have not been validated under conditions which utilize an artificial lung, such cardiopulmonary bypass (CPB). The purpose of this study was to (1) validate the use of tcCO2 using an artificial lung during CPB and (2) identify a location for the sensor that would optimize estimation of PaCO2 when compared to the gold standard of blood gas analysis. tcCO2 measurements ( N = 185) were collected every 30 min during 54 pulsatile CPB procedures. The agreement/differences between the tcCO2 and the PaCO2 were compared by three sensor locations. Compared to the earlobe or the forehead, the submandibular PtcCO2 values agreed best with the PaCO2 and with a median difference of –.03 mmHg (IQR = 5.4, p < 0.001). The small median difference and acceptable IQR support the validity of the tcCO2 measurement. The multiple linear regression model for predicting the agreement between the submandibular tcCO2 and PaCO2 included the SvO2, the oxygenator gas to blood flow ratio, and the native perfusion index ( R2 = 0.699, df = 1, 60; F = 19.1, p < 0.001). Our experience in utilizing tcCO2 during CPB has demonstrated accuracy in estimating PaCO2 when compared to the gold standard arterial blood gas analysis, even during CO2 flooding of the surgical field.

Reference intervals for venous blood gas measurement in adults

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Kirsty L. Ress ◽  
Gus Koerbin ◽  
Ling Li ◽  
Douglas Chesher ◽  
Phillip Bwititi ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Meta Analysis ◽  
Venous Blood ◽  
Reference Interval ◽  
Reference Intervals ◽  
Published Data ◽  
Blood Gas ◽  
Arterial Blood Gas ◽  
Arterial Blood ◽  
Venous Blood Gas

AbstractObjectivesVenous blood gas (VBG) analysis is becoming a popular alternative to arterial blood gas (ABG) analysis due to reduced risk of complications at phlebotomy and ease of draw. In lack of published data, this study aimed to establish reference intervals (RI) for correct interpretation of VBG results.MethodsOne hundred and 51 adult volunteers (101 females, 50 males 18–70 y), were enrolled after completion of a health questionnaire. Venous blood was drawn into safePICO syringes and analysed on ABL827 blood gas analyser (Radiometer Pacific Pty. Ltd.). A non-parametric approach was used to directly establish the VBG RI which was compared to a calculated VBG RI based on a meta-analysis of differences between ABG and VBGResultsAfter exclusions, 134 results were used to derive VBG RI: pH 7.30–7.43, partial pressure of carbon dioxide (pCO2) 38–58 mmHg, partial pressure of oxygen (pO2) 19–65 mmHg, bicarbonate (HCO3−) 22–30 mmol/L, sodium 135–143 mmol/L, potassium 3.6–4.5 mmol/L, chloride 101–110 mmol/L, ionised calcium 1.14–1.29 mmol/L, lactate 0.4–2.2 mmol/L, base excess (BE) −1.9–4.5 mmol/L, saturated oxygen (sO2) 23–93%, carboxyhaemoglobin 0.4–1.4% and methaemoglobin 0.3–0.9%. The meta-analysis revealed differences between ABG and VBG for pH, HCO3−, pCO2 and pO2 of 0.032, −1.0 mmol/L, −4.2 and 39.9 mmHg, respectively. Using this data along with established ABG RI, calculated VBG RI of pH 7.32–7.42, HCO3− 23 – 27 mmol/L, pCO2 36–49 mmHg (Female), pCO2 39–52 mmHg (Male) and pO2 43–68 mmHg were formulated and compared to the VBG RI of this study.ConclusionsAn adult reference interval has been established to assist interpretation of VBG results.

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.

Pregnant sheep develop hypoxaemia during short-term anaesthesia for caesarean delivery

2018 ◽  
Vol 52 (5) ◽  
pp. 497-503
Author(s):  
Gabrielle C Musk ◽  
Matthew W Kemp
Keyword(s):  
Partial Pressure ◽  
Endotracheal Tube ◽  
Caesarean Delivery ◽  
Supplemental Oxygen ◽  
Blood Gas ◽  
Short Term ◽  
Blood Samples ◽  
Arterial Blood ◽  
Pregnant Sheep ◽  
Pregnant Ewe

Short-term anaesthesia of the pregnant ewe may be required for caesarean delivery of a preterm foetus within a research protocol. The aim of this study was to evaluate and compare the acid-base and haematological status of the ewe and foetus at the time of surgical delivery by collecting maternal and foetal arterial blood samples. Fifteen date-mated singleton-pregnant merino cross ewes at 122.0 (±0.5) days of gestation were anaesthetised with a combination of midazolam (0.5 mg/kg) and ketamine (10 mg/kg) by intravenous injection. A subarachnoid injection of lidocaine (60 mg) was given to desensitise the caudal abdomen. Supplemental oxygen was not provided, and an endotracheal tube was not placed in the ewe’s trachea. The development of maternal respiratory acidosis (hypercapnia) and hypoxaemia was anticipated. Samples of arterial blood for blood gas analyses were collected simultaneously from the radial artery of the ewe and the umbilical artery of the foetus immediately after delivery. The results from the maternal blood samples were within the normal range for pH, partial pressure of carbon dioxide in arterial blood (PaCO2), base excess, glucose, lactate, haematocrit and haemoglobin concentration. The maternal partial pressure of oxygen in arterial blood (PaO2) revealed hypoxaemia: 45.2 (41.1–53.4) mmHg. Foetal arterial blood gas analysis revealed hypoxaemia (15.0 ± 3.1 mmHg) and hypoglycaemia (0.1 (0.1–1.1) mmol/L). The benefit of providing supplemental oxygen and/or placing an endotracheal tube must be carefully weighed against the benefit of saving time when prompt delivery of the foetus is planned. In this study the pregnant ewe developed severe hypoxaemia, and this abnormality may have contributed to a low foetal PaO2.

Gas Exchange

2017 ◽  
Author(s):  
John W. Kreit
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Partial Pressure ◽  
Capillary Blood ◽  
Pressure Gradients ◽  
Arterial Blood ◽  
Pulmonary Capillary ◽  
Partial Pressures ◽  
Pulmonary Capillary Blood ◽  
And Diffusion

Gas Exchange explains how four processes—delivery of oxygen, excretion of carbon dioxide, matching of ventilation and perfusion, and diffusion—allow the respiratory system to maintain normal partial pressures of oxygen (PaO2) and carbon dioxide (PaCO2) in the arterial blood. Partial pressure is important because O2 and CO2 molecules diffuse between alveolar gas and pulmonary capillary blood and between systemic capillary blood and the tissues along their partial pressure gradients, and diffusion continues until the partial pressures are equal. Ventilation is an essential part of gas exchange because it delivers O2, eliminates CO2, and determines ventilation–perfusion ratios. This chapter also explains how and why abnormalities in each of these processes may reduce PaO2, increase PaCO2, or both.

Sign in / Sign up

Export Citation Format

Share Document