scholarly journals Tissue oxidative metabolism after extreme hemodilution with PEG-conjugated hemoglobin

2010 ◽  
Vol 109 (6) ◽  
pp. 1852-1859 ◽  
Author(s):  
Pedro Cabrales ◽  
Fantao Meng ◽  
Seetharama A. Acharya
Keyword(s):  
Energy State ◽  
Capillary Density ◽  
Functional Capillary Density ◽  
Acid Base Balance ◽  
Noninvasive Technique ◽  
Isovolemic Hemodilution ◽  
Blood Flows ◽  
Arterial Blood ◽  
Base Balance ◽  
Chamber Model

NADH-localized fluorometry was used as a noninvasive technique to monitor changes in the energy state of intact tissue (muscle and connective tissue), without anesthesia, as a function of blood plasma O2-carrying capacity in the hamster window chamber model. Acute moderate isovolemic hemodilution was induced by two isovolemic hemodilution steps: in the first step, 6% 70-kDa dextran (Dex70) was used to induce an acute anemic state (18% Hct); in the second step, exchange transfusion of polyethylene glycol (PEG) maleimide-conjugated Hb (4 g/dl, PEG-Hb) or Dex70 (6 g/dl) was used to reduce erythrocytes to 75% of baseline (11% Hct). PEG-Hb had six copies of PEG (5 kDa) conjugated to each human Hb (0.48 g PEG/g Hb) through extension arm-facilitated chemistry. Systemic parameters, microvascular perfusion, functional capillary density, intravascular and interstitial Po2, and intracellular NADH fluorescence were monitored. Mean arterial blood pressure after extreme hemodilution was statistically significantly reduced for Dex70 compared with PEG-Hb. The presence of PEG-Hb in the circulation maintained positive acid-base balance. While microvascular blood flows were not different, functional capillary density was significantly higher for PEG-Hb than Dex70. Arteriolar Po2 was higher in the presence of PEG-Hb than Dex70, but tissue and venular Po2 were not different. Cellular energy metabolism (intracellular O2) in the tissues was improved with PEG-Hb. Moderate hemodilution to 18% Hct (6.4 g Hb/dl) brings tissue O2 delivery to the verge of inadequacy. Extreme hemodilution to 11% Hct (3.7 g Hb/dl) produces tissue anoxia, and high-O2-affinity PEG-Hb (Po2 at which blood is 50% saturated with O2 = 4 Torr, 1.1 g Hb/dl) only partially decreases anaerobic metabolism without increasing tissue Po2.

Plasma viscosity regulates systemic and microvascular perfusion during acute extreme anemic conditions

2006 ◽  
Vol 291 (5) ◽  
pp. H2445-H2452 ◽  
Author(s):  
Pedro Cabrales ◽  
Amy G. Tsai
Keyword(s):  
Flow Distribution ◽  
Capillary Density ◽  
High Viscosity ◽  
Plasma Viscosity ◽  
Functional Capillary Density ◽  
Microvascular Perfusion ◽  
Arterial Blood ◽  
Chamber Model ◽  
Kidney Liver ◽  
Window Chamber

The hamster window chamber model was used to study systemic and microvascular hemodynamic responses to extreme hemodilution with low- and high-viscosity plasma expanders (LVPE and HVPE, respectively) to determine whether plasma viscosity is a factor in homeostasis during extreme anemic conditions. Moderated hemodilution was induced by two isovolemic steps performed with 6% 70-kDa dextran until systemic hematocrit (Hct) was reduced to 18% ( level 2). In a third isovolemic step, hemodilution with LVPE (6% 70-kDa dextran, 2.8 cP) or HVPE (6% 500-kDa dextran, 5.9 cP) reduced Hct to 11%. Systemic parameters, cardiac output (CO), organ flow distribution, microhemodynamics, and functional capillary density, were measured after each exchange dilution. Fluorescent-labeled microspheres were used to measure organ (brain, heart, kidney, liver, lung, and spleen) and window chamber blood flow. Final blood and plasma viscosities after the entire protocol were 2.1 and 1.4 cP, respectively, for LVPE and 2.8 and 2.2 cP, respectively, for HVPE (baseline = 4.2 and 1.2 cP, respectively). HVPE significantly elevated mean arterial pressure and CO compared with LVPE but did not increase vascular resistance. Functional capillary density was significantly higher for HVPE [87% (SD 7) of baseline] than for LVPE [42% (SD 11) of baseline]. Increases in mean arterial blood pressure, CO, and shear stress-mediated factors could be responsible for maintaining organ and microvascular perfusion after exchange with HVPE compared with LVPE. Microhemodynamic data corresponded to microsphere-measured perfusion data in vital organs.

DIGITALIS TOLERANCE IN YOUNG PUPPIES

PEDIATRICS ◽  
1970 ◽  
Vol 46 (5) ◽  
pp. 730-736
Author(s):  
Katherine H. Halloran ◽  
Steven C. Schimpff ◽  
Jean G. Nicolas ◽  
Norman S. Talner
Keyword(s):  
Blood Gases ◽  
Acid Base Balance ◽  
Acid Base ◽  
Littermate Control ◽  
Premature Ventricular Contractions ◽  
Toxic Dose ◽  
Arterial Blood ◽  
Wide Range ◽  
Base Balance ◽  
The Mean

Tolerance to acetyl strophanthidin, a rapid-acting cardiac aglycone, was determined in 28 anesthetized mongrel puppies, ages 16 to 56 days, and compared to tolerance in 16 littermate puppies in whom acute hypercapnic acidemia was produced. The tolerance was also compared to that of four adult mongrel dogs. The toxic dose was defined as the intravenous amount required to produce four consecutive premature ventricular contractions. A marked variation in the toxic dose was found in the 28 control puppies (range 83 to 353 µg/kg, mean 169 µg/kg) which could not be correlated with age, arterial blood gases or pH, serum potassium or sodium, arterial pressure, or heart rate. The toxic dose was significantly greater in the puppies than in the adult dogs, in whom the mean toxic dose was 64 µg/kg (range 50 to 89 µg/kg). A significant increase in tolerance was also observed in the puppies with hypercapnic acidemia (mean toxic dose 220 µg/kg, range 93 to 375 µg/kg) in comparison to tolerance in the control puppies and despite the wide range of tolerance, each of the puppies with hypercapnic acidemia showed greater tolerance than its littermate control puppy. Assessment of the clinical implications of these findings will require study of the effects of alterations in acid-base balance on the inotropic effect of acetyl strophanthidin in addition to the toxic electrophysiologic effects.

scholarly journals April 2021 Critical Care Case of the Month: Abnormal Acid-Base Balance in a Post-Partum Woman

2021 ◽  
Vol 22 (4) ◽  
pp. 81-85
Author(s):  
Mohammad Mahmoud ◽  
Keyword(s):  
Emergency Department ◽  
Complete Blood Count ◽  
Post Partum ◽  
Healthy Woman ◽  
Blood Gases ◽  
Ambient Air ◽  
Physical Exam ◽  
Acid Base Balance ◽  
Arterial Blood ◽  
Base Balance

No abstract available. Article truncated after first page. History of Present Illness: A 29-year-old healthy woman, who is 8 weeks postpartum, presented to the emergency department with severe shortness of breath, fast shallow breathing, nausea, several episodes of nonbloody nonbilious emesis, abdominal pain and malaise for 1 week. The patient delivered a healthy boy at full-term by spontaneous vaginal delivery. Her pregnancy was uneventful. She denied smoking or use of alcohol. Physical Exam: On presentation to the emergency department her blood pressure was found to be 121/71, temperature 36.8°C, pulse 110 beats per minute, respiratory rate 20 breaths per minute and SpO2 saturation of 99% while breathing ambient air. Physical exam was remarkable except for dry mucous membranes, sinus tachycardia, and tachypnea with mild epigastric tenderness with light palpation. Which of the following should be done? 1. Complete blood count (CBC) 2. Metabolic panel 3. Chest x-ray 4. Arterial blood gases (ABGs) 5. All of the above …

The effects of enforced activity on ventilation, circulation and blood acid-base balance in the aquatic gill-less urodele, Cryptobranchus alleganiensis; a comparison with the semi-terrestrial anuran, Bufo marinus

1980 ◽  
Vol 84 (1) ◽  
pp. 289-302
Author(s):  
R. G. Boutilier ◽  
D. G. McDonald ◽  
D. P. Toews
Keyword(s):  
Recovery Period ◽  
Respiratory Acidosis ◽  
Bufo Marinus ◽  
Acid Base Balance ◽  
Acid Base ◽  
Post Exercise ◽  
Arterial Blood ◽  
Cryptobranchus Alleganiensis ◽  
Base Balance ◽  
Lower Magnitude

A combined respiratory and metabolic acidosis occurs in the arterial blood immediately following 30 min of strenuous activity in the predominantly skin-breathing urodele, Cryptobranchus alleganiensis, and in the bimodal-breathing anuran, Bufo marinus, at 25 degrees C. In Bufo, the bulk of the post-exercise acidosis is metabolic in origin (principally lactic acid) and recovery is complete within 4-8 h. In the salamander, a lower magnitude, longer duration, metabolic acid component and a more pronounced respiratory acidosis prolong the recovery period for up to 22 h post-exercise. It is suggested that fundamental differences between the dominant sites for gas exchange (pulmonary versus cutaneous), and thus in the control of respiratory acid-base balance, may underline the dissimilar patterns of recovery from exercise in these two species.

The effects of enforced activity on ventilation, circulation and blood acid-base balance in the semi-terrestrial anuran, Bufo marinus

1980 ◽  
Vol 84 (1) ◽  
pp. 273-287
Author(s):  
D. G. McDonald ◽  
R. G. Boutilier ◽  
D. P. Toews
Keyword(s):  
Time Course ◽  
Ventilation Rate ◽  
Strenuous Exercise ◽  
Acid Base Balance ◽  
Acid Base ◽  
Arterial Blood ◽  
Base Balance ◽  
Lactate Levels ◽  
Acid Base Disturbance ◽  
Base Disturbance

Strenuous exercise results in a marked blood acid-base disturbance which is accompanied by large increases in ventilation rate, heart rate and mean arterial blood pressure. Recovery to normal resting values follows an exponential time course with a half-time of approximately 2 h for all parameters except Pa, CO2 and ventilation rate. The latter return to normal by 30 min following the exercise period. Analysis reveals that there is initially a large discrepancy between the quantity of metabolic acids buffered in the blood and the blood lactate levels. The significance of this finding is discussed. Significant changes in the concentrations of chloride, bicarbonate and lactate, in both plasma and erythrocytes, accompany the blood acid-base disturbance. Chloride and bicarbonate appear to be passively distributed between the two compartments according to a Gibbs-Donnan equilibrium whereas lactate only slowly permeates the erythrocyte.

scholarly journals Association between Acid-Base Balance and Asphyxia in Newborn Infants

2018 ◽  
Vol 34 (1-2) ◽  
pp. 38-43
Author(s):  
Sari Leyli Harahap ◽  
Chairul Adillah Harahap ◽  
Sri Sulastri ◽  
Chairul Yoel ◽  
Noersida Raid
Keyword(s):  
Apgar Score ◽  
Newborn Infants ◽  
Blood Gas Analysis ◽  
Gas Analysis ◽  
Blood Gas ◽  
Acid Base Balance ◽  
Acid Base ◽  
Apgar Scores ◽  
Arterial Blood ◽  
Base Balance

We performed a prospective study on the association between acid-base balance and asphyxta based on Apgar scores in 45 newborn babies admitted to the Division of Perinatology, Pirngadi Hospital, Medan, from January 1 to February 28, 1993. Blood gas analysis was done on blood obtained from umbilical artery. Based on 1st and 5th minutes Apgar scores, 40 (88.9%) and 21 babies (46.7%}, respectively, had asphyxia. Relation to acid-base balance was determined with the sensitivity of the 5th minute Apgar score in predicting acidotic states. It was found that Apgar score had sensitivity of 57.7% and specificity of 68.4% in predicting the acidotic states. Apgar score of > 7 was unable to. exclude the possible acidosis in 45% of cases (negative predictive value 54.1%). Gestational age had no influence on Apgar Scores. Apgar score was more sensitive to eliminate suspected acidosis in term neonates than in preterms. We recommend to perform umbilical arterial blood gas analysis to determine acidotic state in high risk newborn infants.

Arterial Blood Gases, Acid-Base Balance, and Lactate and Gas Exchange Variables During Hypoxic Exercise

1989 ◽  
Vol 10 (04) ◽  
pp. 279-285 ◽  
Author(s):  
T. Yoshida ◽  
M. Udo ◽  
M. Chida ◽  
K. Makiguchi ◽  
M. Ichioka ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Blood Gases ◽  
Arterial Blood Gases ◽  
Acid Base Balance ◽  
Acid Base ◽  
Arterial Blood ◽  
Base Balance ◽  
Hypoxic Exercise

Effect of Multimodal Anesthesia on the Hemodynamic Profile and Acid-Base Balance in the Early Post-Operative Period in Patients Operated for Lung Tumors

2015 ◽  
Vol 22 (4) ◽  
pp. 63-73
Author(s):  
Качур ◽  
S. Kachur ◽  
Долгих ◽  
V. Dolgikh
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Ejection Fraction ◽  
Lung Tumors ◽  
Acid Base Balance ◽  
Acid Base ◽  
Arterial Blood ◽  
Post Operative Period ◽  
Base Balance ◽  
Hemodynamic Profile

This work presents the effects of multimodal anesthesia with neuraxial blockade on the basic parameters of central hemodynamics in patients operated for lung tumors, revealed by method of terapolar rheovasography by Kubicek (systolic blood pressure, diastolic, average heart rate, ejection fraction, minute volume of blood circulation, cardiac index, oxygen delivery index, the index of the total peripheral vascular resistance), as well the effects on acid‐base balance of arterial blood in the immediate post‐operative period. The level of antinociceptive protection was assessed by visual analogue scale. Comparison of results of patients operated by means of multimodal anesthesia and the patients, operated in an inhalation intravenous anesthesia with artificial lung ventilation and peri‐operative analgesia by opioid analgesics has revealed that the hemodynamic profile of the first group of patients is characterized by stability of the basic parameters such as blood pressure and heart rate, the lack of a pronounced reduction of the ejection fraction and stroke volume of the heart, despite vasoplegia caused by epidural blockade. The level of partial oxygen tension of arterial blood was decreased in the early postoperative period, but it was in the normal limits and he was statistically significantly higher than in the comparison group that can help reduce the risk of post‐operative complications. Significantly lower level of pain indicates adequate antinociceptive protection of patients.

scholarly journals Isoflurane-induced acidosis depresses basal and PGE2-stimulated duodenal bicarbonate secretion in mice

2007 ◽  
Vol 292 (3) ◽  
pp. G899-G904 ◽  
Author(s):  
Markus Sjöblom ◽  
Olof Nylander
Keyword(s):  
Base Excess ◽  
Ringer Solution ◽  
Bicarbonate Secretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
In Vivo Experiments ◽  
Arterial Blood ◽  
Blood Ph ◽  
Base Balance

When running in vivo experiments, it is imperative to keep arterial blood pressure and acid-base parameters within the normal physiological range. The aim of this investigation was to explore the consequences of anesthesia-induced acidosis on basal and PGE2-stimulated duodenal bicarbonate secretion. Mice (strain C57bl/6J) were kept anesthetized by a spontaneous inhalation of isoflurane. Mean arterial blood pressure (MAP), arterial acid-base balance, and duodenal mucosal bicarbonate secretion (DMBS) were studied. Two intra-arterial fluid support strategies were used: a standard Ringer solution and an isotonic Na2CO3 solution. Duodenal single perfusion was used, and DMBS was assessed by back titration of the effluent. PGE2 was used to stimulate DMBS. In Ringer solution-infused mice, isoflurane-induced acidosis became worse with time. The blood pH was 7.15–7.21 and the base excess was about −8 mM at the end of experiments. The continuous infusion of Na2CO3 solution completely compensated for the acidosis. The blood pH was 7.36–7.37 and base excess was about 1 mM at the end of the experiment. Basal and PGE2-stimulated DMBS were markedly greater in animals treated with Na2CO3 solution than in those treated with Ringer solution. MAP was slightly higher after Na2CO3 solution infusion than after Ringer solution infusion. We concluded that isoflurane-induced acidosis markedly depresses basal and PGE2-stimulated DMBS as well as the responsiveness to PGE2, effects prevented by a continuous infusion of Na2CO3. When performing in vivo experiments in isoflurane-anesthetized mice, it is recommended to supplement with a Na2CO3 infusion to maintain a normal acid-base balance.

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