The Ventilatory Response in Severe Metabolic Acidosis

1976 ◽  
Vol 50 (5) ◽  
pp. 367-373 ◽  
Author(s):  
M. Fulop
Keyword(s):  
Metabolic Acidosis ◽  
Ventilatory Response ◽  
Acute Hypoxia ◽  
Carbon Dioxide Tension ◽  
Pulmonary Insufficiency ◽  
Plasma Lactate ◽  
Severe Metabolic Acidosis ◽  
Arterial Blood ◽  
Blood Ph ◽  
Insufficient Time

1. The ventilatory response to severe metabolic acidosis was studied by measuring arterial blood carbon dioxide tension and pH in sixty-seven patients with blood pH < 7·10, none of whom had hypercapnia, pulmonary oedema, or chronic pulmonary insufficiency. The results were compared with those previously found in patients with uncomplicated diabetic ketoacidosis. 2. By that comparison, fifty-two of the sixty-seven patients with blood pH < 7·10 were judged to have ‘appropriate hypocapnia’, and fifteen had ‘submaximal hypocapnia’. Thirteen of the latter fifteen had circulatory failure and/or acute hypoxia, and seven of nine in whom it was measured had plasma lactate >9 mmol/l. 3. Hyperventilation was therefore usually well sustained in these patients with severe metabolic acidosis, except in most of those with acute tissue hypoxia. The latter may have had insufficient time to achieve maximum hyperventilation in response to their acidosis, or perhaps their submaximal hypercapnia presaged imminent failure of the hyperventilatory response.

The Ventilatory Response in Diabetic Ketoacidosis

1974 ◽  
Vol 46 (4) ◽  
pp. 539-549 ◽  
Author(s):  
M. Fulop ◽  
N. Dreyer ◽  
H. Tannenbaum
Keyword(s):  
Metabolic Acidosis ◽  
Diabetic Ketoacidosis ◽  
Ventilatory Response ◽  
Hydrogen Ion ◽  
Inverse Relation ◽  
Bicarbonate Concentration ◽  
Plasma Bicarbonate ◽  
Arterial Blood ◽  
Blood Ph ◽  
Ion Activity

1. Previous studies of the ventilatory response to metabolic acidosis have usually considered only patients with arterial blood pH above 7·10. To define the response during more severe acidaemia, arterial CO2 tension and pH were measured in fifty-three episodes of diabetic ketoacidosis, including twenty-four with pH below 7·10, and ten with pH below 7·00. 2. The relation between arterial CO2 tension, and both blood pH and plasma bicarbonate concentration, in these cases with generally severe metabolic acidaemia (mean pH 7·12 ± SD 0·13), was very similar to the relations between those variables found by others in patients with less severe acidaemia, such as that due to renal failure. 3. As arterial blood hydrogen ion activity increased, arterial CO2 tension decreased inversely, reflecting well-sustained hyperventilation, even during profound acidaemia. 4. The inverse relation between arterial CO2 tension and hydrogen ion activity suggests that during metabolic acidosis, alveolar ventilation increases in direct proportion to the increased blood hydrogen ion activity.

ERRATA

PEDIATRICS ◽  
1980 ◽  
Vol 65 (5) ◽  
pp. 1006-1006
Keyword(s):  
Metabolic Acidosis ◽  
Diagnostic Approach ◽  
Acid Base ◽  
Arterial Blood ◽  
Blood Ph ◽  
P 351 ◽  
Normal Acid

In the article "A Diagnostic Approach to Metabolic Acidosis in Children" by Kappy and Morrow (Pediatrics 65:351-356, 1980) on p 351 under "Normal Acid-Base Physiology" the normal arterial blood pH is maintained at 7.40 (H+ = 39.8 nEq/liter not mEq/liter.

31P-NMR in vivo measurement of renal intracellular pH: effects of acidosis and K+ depletion in rats

1986 ◽  
Vol 251 (5) ◽  
pp. F904-F910 ◽  
Author(s):  
W. R. Adam ◽  
A. P. Koretsky ◽  
M. W. Weiner
Keyword(s):  
Metabolic Acidosis ◽  
Intracellular Ph ◽  
Respiratory Acidosis ◽  
Resonance Spectroscopy ◽  
Ph Effects ◽  
Potassium Depletion ◽  
Chronic Metabolic Acidosis ◽  
Arterial Blood ◽  
Blood Ph

Renal intracellular pH (pHi) was measured in vivo from the chemical shift (sigma) of inorganic phosphate (Pi), obtained by 31P-nuclear magnetic resonance spectroscopy (NMR). pH was calculated from the difference between sigma Pi and sigma alpha-ATP. Changes of sigma Pi closely correlated with changes of sigma monophosphoesters; this supports the hypothesis that the pH determined from sigma Pi represents pHi. Renal pH in control rats was 7.39 +/- 0.04 (n = 8). This is higher than pHi of muscle and brain in vivo, suggesting that renal Na-H antiporter activity raises renal pHi. To examine the relationship between renal pH and ammoniagenesis, rats were subjected to acute (less than 24 h) and chronic (4-7 days) metabolic acidosis, acute (20 min) and chronic (6-8 days) respiratory acidosis, and dietary potassium depletion (7-21 days). Acute metabolic and respiratory acidosis produced acidification of renal pHi. Chronic metabolic acidosis (arterial blood pH, 7.26 +/- 0.02) lowered renal pHi to 7.30 +/- 0.02, but chronic respiratory acidosis (arterial blood pH, 7.30 +/- 0.05) was not associated with renal acidosis (pH, 7.40 +/- 0.04). At a similar level of blood pH, pHi was higher in chronic metabolic acidosis than in acute metabolic acidosis, suggesting an adaptive process that raises pHi. Potassium depletion (arterial blood pH, 7.44 +/- 0.05) was associated with a marked renal acidosis (renal pH, 7.17 +/- 0.02). There was a direct relationship between renal pH and cardiac K+. Rapid partial repletion with KCl (1 mmol) significantly increased renal pHi from 7.14 +/- 0.03 to 7.31 +/- 0.01.(ABSTRACT TRUNCATED AT 250 WORDS)

Control of breathing in Sherpas at low and high altitude

1980 ◽  
Vol 49 (3) ◽  
pp. 374-379 ◽  
Author(s):  
P. H. Hackett ◽  
J. T. Reeves ◽  
C. D. Reeves ◽  
R. F. Grover ◽  
D. Rennie
Keyword(s):  
High Altitude ◽  
Ventilatory Response ◽  
Minute Ventilation ◽  
Acute Hypoxia ◽  
Arterial Oxygen Saturation ◽  
Carbon Dioxide Tension ◽  
Arterial Oxygen ◽  
Hypoxic Ventilatory Response ◽  
Oxygen Administration ◽  
End Tidal

Sherpas are well known for their physical performance at extreme altitudes, yet they are reported to have blunted ventilatory responses to acute hypoxia and relative hypoventilation in chronic hypoxia. To examine this paradox, we studied ventilatory control in Sherpas in comparison to that in Westerners at both low and high altitude. At low altitude, 25 Sherpas had higher minute ventilation, higher respiratory frequency, and lower end-tidal carbon dioxide tension than 25 Westerners. The hypoxic ventilatory response of Sherpas was found to be similar to that in Westerners, even though long altitude exposure had blunted the responses of some Sherpas. At high altitude, Sherpas again had higher minute ventilation and a tendency toward higher arterial oxygen saturation than Westerners. Oxygen administration increased ventilation further in Sherpas but decreased ventilation in Westerners. We conclude that Sherpas differ from other high-altitude natives; their hypoxic ventilatory response is not blunted, and they exhibit relative hyperventilation.

scholarly journals Selected Arterial Blood Gasometry Parameters as Indicators of Blood Transfusion Effectiveness in Foals with Haemolytic Disease

2014 ◽  
Vol 58 (3) ◽  
pp. 467-471
Author(s):  
Artur Stopyra ◽  
Anna Snarska
Keyword(s):  
Carbon Dioxide ◽  
Blood Transfusion ◽  
Partial Pressure ◽  
Carbon Dioxide Tension ◽  
Haematological Parameters ◽  
Haemolytic Disease ◽  
Transfusion Therapy ◽  
Arterial Blood ◽  
Blood Ph ◽  
Ph Increase

Abstract The aim of the study was to determine the suitability of basic haematological, biochemical, and gasometric tests in checking the effectiveness of transfusion therapy in foals during isoerythrolysis. The number of red blood cells, haemoglobin, haematocrit, and partial pressure of carbon dioxide, oxygen, and blood pH was determined immediately before and several times after blood transfusion. The concentration of serum free bilirubin was also measured to confirm haemolysis. Fluids (0.9% NaCl, multielectrolytic fluid, 5% glucose) and antibiotics (penicillin, amikacin) were provided to the foals. The lowest values of haematological parameters were observed before transfusion. This was accompanied by decreased partial pressure of oxygen, low pH, and increased arterial carbon dioxide tension. Transfusion of whole blood led to a gradual normalisation of the haematological parameters, also accompanied by the normalisation of gasometric indicators (decrease in pCO2 and pO2 and pH increase). Monitoring of selected haematological and gasometric parameters allows to evaluate the efficacy of blood transfusion during treatment of haemolytic disease of foals.

Effects of metabolic acidosis and alkalosis on coronary blood flow and myocardial metabolism in the intact dog

1961 ◽  
Vol 200 (3) ◽  
pp. 628-632 ◽  
Author(s):  
A. V. N. Goodyer ◽  
W. F. Eckhardt ◽  
R. H. Ostberg ◽  
M. J. Goodkind
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Metabolic Acidosis ◽  
Coronary Blood Flow ◽  
Venous Blood ◽  
Left Ventricular ◽  
Myocardial Uptake ◽  
Severe Metabolic Acidosis ◽  
Glucose Levels ◽  
Arterial Blood

Severe metabolic acidosis and alkalosis were induced in anesthetized dogs by the infusion of solutions of hydrochloric acid and sodium bicarbonate. Infusions of sodium chloride were administered to other dogs under the same experimental circumstances. Measurements were made of arterial blood pressure, heart rate, cardiac output and coronary blood flow, arterial blood pH, and the content of oxygen, total CO2, lactate, pyruvate and glucose in both arterial and coronary venous blood. The cardiac output and coronary blood flow were decreased by acidosis and increased by alkalosis, the changes induced by alkalosis. There were no significant changes of left ventricular efficiency. Acidosis increased blood glucose concentrations and interfered with the increased myocardial uptake of glucose expected at higher arterial glucose levels. Alkalosis increased blood lactate and pyruvate levels and, correspondingly, the myocardial uptake of these carbohydrate substrates. It is concluded that cardiac dynamic function (as indicated by measurements of cardiac efficiency and output and arterial pressure) is much less affected by severe metabolic acidosis in the intact animal than in the isolated perfused organ.

Effect of metabolic acidosis on proximal tubular total CO2 absorption

1985 ◽  
Vol 249 (1) ◽  
pp. F62-F68 ◽  
Author(s):  
R. T. Kunau ◽  
J. I. Hart ◽  
K. A. Walker
Keyword(s):  
Metabolic Acidosis ◽  
Proximal Tubule ◽  
Brush Border Membrane ◽  
Membrane Vesicles ◽  
Co2 Absorption ◽  
Arterial Blood ◽  
Blood Ph ◽  
In Series ◽  
Proximal Tubular

In vivo microperfusion studies of the proximal convoluted tubule of the rat were performed to determine the effect of metabolic acidosis on total CO2 (tCO2) absorption. In series I, tubular perfusion was performed in control and acidotic rats in a manner by which similar mean total CO2 concentrations in the proximal tubule were maintained. Comparable ranges of perfusion rate were studied in both groups. Following 3 days of HCl ingestion, plasma tCO2 was 20.0 +/- 0.9 mM in the acidotic rats whereas it was 29.6 +/- 0.53 mM in control rats. The arterial blood pH values were 7.25 +/- 0.02 vs. 7.43 +/- 0.01. Starting tCO2 perfusate concentrations were identical in both groups, 29.3 and 29.7 mM, as were the concentrations at the end of the perfused segments, 21.2 and 21.9 mM. The absorption of tCO2 (JtCO2, pmol X mm-1 X min-1) was significantly greater in the acidotic rats than in the controls, 576 +/- 39 vs. 256 +/- 21. At all perfusion rates studied, proximal tubular JtCO2 was higher in the acidotic than in the control rats. In series II, similar lengths of the late proximal tubule were perfused at the same rate in control and acidotic rats. Again, JtCO2 was higher in the acidotic rats, 352 +/- 19 vs. 198 +/- 13. The results indicate that at comparable luminal tCO2 concentration and tubular fluid flow rates, tCO2 absorption is significantly increased in the acidotic state. Although other mechanisms cannot be excluded, the finding of an increase in proximal tCO2 absorption in the acidotic rats is in agreement with the presence of an accelerated Na+/H+ exchange rate in brush border membrane vesicles obtained from the renal cortex of animals with metabolic acidosis.

The Respiratory Response to Chronic Metabolic Alkalosis and Acidosis in Disease

1973 ◽  
Vol 45 (4) ◽  
pp. 439-448 ◽  
Author(s):  
C. van Ypersele de Strihou ◽  
A. Frans
Keyword(s):  
Metabolic Alkalosis ◽  
Carbon Dioxide Tension ◽  
Individual Response ◽  
Chronic Haemodialysis ◽  
Confidence Limits ◽  
Respiratory Response ◽  
Acid Base ◽  
Arterial Blood ◽  
Blood Ph ◽  
The Individual

1. The respiratory response to chronic metabolic alkalosis was defined on the basis of 182 determinations of the arterial blood pH, Pco2, HCO3− concentration and Po2 obtained in thirty uraemic patients undergoing chronic haemodialysis. Plasma bicarbonate concentrations, [HCO3−], ranged from 20 to 38 mmol/l before dialysis, and were elevated by increasing the acetate content of the dialysate. 2. The calculated arterial carbon dioxide tension (Pa,co2) was linearly related to HCO3−, Pa,co2 reaching 50 mmHg at a [HCO3−] of 37.5 mmol/l. This response was virtually identical with that previously reported in chronic metabolic acidosis. The 95% confidence limits of the respiratory adaptation to chronic metabolic acid-base disorders were calculated for [HCO3−] ranging from 11 to 38 mmol/l. 3. Analysis of the individual response lines of thirteen patients revealed no difference among their slopes but significant differences among their elevations. Each subject appears thus to have his own threshold to acid-base stimuli. 4. Hypoxaemia developed with increasing [HCO3−], Pa,o2 falling in a curvilinear fashion to reach 70 mmHg at a [HCO3−] of 37.5 mmol/l.

Impaired ventilatory acclimatization to hypoxia in female mice overexpressing erythropoietin: unexpected deleterious effect of estradiol in carotid bodies

2010 ◽  
Vol 299 (6) ◽  
pp. R1511-R1520 ◽  
Author(s):  
Max Gassmann ◽  
Christine Pfistner ◽  
Van Diep Doan ◽  
Johannes Vogel ◽  
Jorge Soliz
Keyword(s):  
Transgenic Mice ◽  
Chronic Hypoxia ◽  
Ventilatory Response ◽  
Acute Hypoxia ◽  
Female Mice ◽  
Arterial Blood ◽  
Carotid Bodies ◽  
Central Brain ◽  
Central Response ◽  
The Brain

Apart from enhancing the production of red blood cells, erythropoietin (Epo) alters the ventilatory response when oxygen supply is reduced. We recently demonstrated that Epo's beneficial effect on the ventilatory response to acute hypoxia is sex dependent, with female mice being better able to cope with reduced oxygenation. In the present work, we hypothesized that ventilatory acclimatization to chronic hypoxia (VAH) in transgenic female mice (Tg6) harboring high levels of Epo in the brain and blood will also be improved compared with wild-type (WT) animals. Surprisingly, VAH was blunted in Tg6 female mice. To define whether this phenomenon had a central (brain stem respiratory centers) and/or peripheral (carotid bodies) origin, a bilateral transection of carotid sinus nerve (chemodenervation) was performed. This procedure allowed the analysis of the central response in the absence of carotid body information. Interestingly, chemodenervation restored the VAH in Tg6 mice, suggesting that carotid bodies were responsible for the blunted response. Coherently with this observation, the sensitivity to oxygen alteration in arterial blood (Dejour test) after chronic hypoxia was lower in transgenic carotid bodies compared with the WT control. As blunted VAH occurred in female but not male transgenic mice, the involvement of sex female steroids was obvious. Indeed, measurement of sexual female hormones revealed that the estradiol serum level was 4 times higher in transgenic mice Tg6 than in WT animals. While ovariectomy decreased VAH in WT females, this treatment restored VAH in Tg6 female mice. In line with this observation, injections of estradiol in ovariectomized Tg6 females dramatically reduced the VAH. We concluded that during chronic hypoxia, estradiol in carotid bodies suppresses the Epo-mediated elevation of ventilation. Considering the increased application of recombinant Epo for a variety of disorders, our data imply the need to take the patient's hormonal status into consideration.

Sign in / Sign up

Export Citation Format

Share Document