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.

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.

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.

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.

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.

Cimetidine-induced prolactin release in rats The effect of sex and gonadal steroids

1987 ◽  
Vol 114 (2) ◽  
pp. 178-184 ◽  
Author(s):  
Hajime Watanobe ◽  
Kazuo Takebe
Keyword(s):  
Anterior Pituitary ◽  
Male Rats ◽  
Minor Role ◽  
Adult Males ◽  
Adult Age ◽  
Significant Difference ◽  
Males And Females ◽  
Plasma Prl ◽  
A Minor

Abstract. The cimetidine-induced plasma Prl response was examined in rats of both sexes. First, 10 week old intact adult males and females (dioestrous) were compared. There was no significant difference in the Prl response to cimetidine between the two groups, despite the fact that in adult females the anterior pituitary Prl content was 4 times greater than in males. Second, the effect of gonadal state in adult age on the Prl response to cimetidine was examined in both sexes. In male rats, gonadectomy at the age of 6 weeks significantly reduced the plasma Prl response as well as the pituitary Prl content, both of which were sufficiently restored by testosterone replacement. However, in females, neither gonadectomy at the age of 6 weeks nor subsequent oestradiol replacement affected the Prl response to cimetidine, despite the fact that gonadectomy significantly reduced and oestradiol treatment significantly enhanced the pituitary Prl content. Third, possible permanent effects of the postnatal gonadal milieu on the cimetidine-induced Prl response and the pituitary Prl content were examined in both sexes by castration at varying postnatal ages. The ratio of plasma Prl response to pituitary Prl content was similar in all castrated males. In females, however, the ratio decreased with increasing castration age. In conclusion, the mechanism of cimetidine-induced Prl release is less sex-dependent than are the mechanisms of Prl release by other Prl secretagogues. First, this may be due to a minor role of oestrogen in females in determining the Prl response to cimetidine. Second, the postnatal ovarian secretions may exert a permanent inhibition of the development of the cimetidine-mobilized anterior pituitary Prl pool.

P18 Plasma-lyte 148 vs 0.9% saline for fluid resuscition in children: electrolytic and clinical outcomes

2018 ◽  
Vol 103 (2) ◽  
pp. e1.22-e1 ◽  
Author(s):  
Wignell Andrew ◽  
Davies Patrick
Keyword(s):  
Clinical Outcomes ◽  
Kidney Injury ◽  
Fluid Volume ◽  
Lower Percentage ◽  
Clinical Effects ◽  
Arterial Blood Gas ◽  
Arterial Blood ◽  
Significant Difference ◽  
Resuscitation Fluid ◽  
Plasma Chloride

AimsCrystalloid fluid boluses are a mainstay of treatment in unwell children, with the traditional fluid of choice being 0.9% saline (NS). However, the use of NS has been associated with an increase in plasma chloride levels and acidosis, leading to kidney injury and other detrimental clinical effects. Plasma-Lyte 148 (PLA) is a balanced, physiological, crystalloid intravenous fluid, which is both calcium-free and isotonic. Its use in place of NS for fluid resuscitation may circumvent hyperchloraemic metabolic acidosis. In May 2015 our hospital altered its standard resuscitation fluid from NS to PLA. We aimed to compare the effect of fluid boluses of NS to those of PLA in children.MethodsAll patients admitted in the 18 month periods before and after the change from NS to PLA, and receiving a fluid bolus in the first 24 hours of admission, were included. Post-surgical patients and those who had undergone haemofiltration were excluded. Arterial blood gas and creatinine values for up to 5 days after bolus fluid administration were examined. Patients were stratified according to the total resuscitation volume (ml/kg), then split into categories determined by the balance of PLA vs. NS.The primary outcome was plasma chloride. Secondary outcomes included blood pH and percentage change in creatinine. Clinical outcomes were length of ventilation and length of PICU stay.Results126 patients were included in the analysis. Patients receiving NS boluses tended to have a higher maximum chloride, higher average chloride, lower pH and higher percentage creatinine increase than those given PLA. Subgroup analysis showed a statistically significant difference in average serum chloride for the 61–90 ml/kg group {PLA 105.59±1.29 vs NS 111.29±2.1 mmol/L; difference: −6.21 [95% confidence interval (CI)−9.55,–2.87]}. Patients who received PLA tended to have a higher pH than those receiving NS. A statistically significant difference was seen in the 10–30 ml/kg group [PLA 7.42±0.49 vs NS 7.33±0.65; difference: 0.0913 (95% CI: −0.18 to −0.02)].Significant differences were not seen in the clinical outcomes of length of stay or ventilationConclusionPLA as a resuscitation fluid is significantly associated with a more physiological plasma chloride and pH across several resuscitation fluid volume categories, when compared to NS. The trends in the other fluid volume categories are in line with these findings, but are not statistically significant. There was also a trend towards patients receiving PLA having a lower percentage rise in creatinine than those who received saline. These results were consistent over all weight and age categories.

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.

Furosemide in Hyaline Membrane Disease

PEDIATRICS ◽  
1978 ◽  
Vol 62 (5) ◽  
pp. 785-788
Author(s):  
Keith H. Marks ◽  
William Berman ◽  
Zvi Friedman ◽  
Victor Whitman ◽  
Cheryl Lee ◽  
...  
Keyword(s):  
Interstitial Fluid ◽  
Hyaline Membrane Disease ◽  
Skinfold Thickness ◽  
Acute Stage ◽  
Control Group ◽  
Arterial Blood Gas ◽  
Cardiorespiratory Function ◽  
Arterial Blood ◽  
Significant Difference ◽  
Hyaline Membrane

In a randomized clinical trial designed to evaluate the effect of diuresis on infants with hyaline membrane disease, seven infants were treated with furosemide (2 mg/kg intravenously) and five received 5% dextrose water in 0.225% sodium chloride (control group). Arterial blood gas analyses performed before and during the six hours after treatment showed no significant difference between control and treated infants. Urine output and urine sodium and calcium loss were significantly increased (P < .05) in the infants receiving furosemide. The diuresis seemed to have no effect on left atrial size determined echocardiographically, whereas measurements of dynamic skinfold thickness suggested mobilization of subcutaneous water. One infant became seriously dehydrated and hypotensive secondary to a massive diuresis. We concluded that furosemide had a potent diuretic effect in infants with hyaline membrane disease but does not improve cardiorespiratory function acutely. This may be because of failure to mobilize pulmonary interstitial fluid in the time period tested. It may also be possible that the presence of pulmonary interstitial fluid does not play an important role in the impairment of gas exchange in the acute stage of hyaline membrane disease.

Derivation of CO2 output from oscillations in arterial pH

1987 ◽  
Vol 62 (3) ◽  
pp. 880-891 ◽  
Author(s):  
B. A. Cross ◽  
R. P. Stidwill ◽  
K. D. Leaver ◽  
S. J. Semple
Keyword(s):  
Maximum Rate ◽  
Venous Blood ◽  
Co2 Flux ◽  
Limited Range ◽  
Co2 Production ◽  
Mixed Venous Blood ◽  
Co2 Partial Pressure ◽  
Co2 Output ◽  
Arterial Ph ◽  
Small Rise

Theory predicts that the rate of rise of the oscillation in arterial CO2 partial pressure (PaCO2) is linearly dependent on CO2 flux from venous blood to alveolar gas. We have measured, in the anesthetized cat, CO2 output (VCO2) and oscillations in arterial pH. The pH signal was differentiated to give the maximum rate of fall of pH on the downstroke of the oscillation (dpH/dt decreases max). Since oscillations in pH are due to oscillations in arterial PCO2, dpH/dt decreases max was considered to be equivalent to the maximum rate of rise of the PCO2 oscillation. VCO2 was increased by ventilating the intestines with CO2 and by the intra-arterial infusion of 2,4-dinitrophenol. VCO2 was decreased by filling the intestines with isotonic tris(hydroxymethyl)methylamine buffer. The maximum range of VCO2 covered was 7.8–51 ml/min, and the mean range was from 13.6 +/- 1.3 to 29.7 +/- 1.6 (SE) ml/min. Although CO2 loading produced a small rise and CO2 unloading a small fall in mean PaCO2, the changes were not statistically significant, so that overall the response was close to isocapnia. Over the limited range of VCO2 studied there was a highly significant linear association between dpH/dt decreases max and VCO2 which supports the contention that the slope of the upstroke of the PaCO2 oscillation is determined by the CO2 flux from mixed venous blood to alveolar gas. As such this slope is a potential chemical signal linking ventilation to CO2 production.

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