Hyperoxic Ventilation Reduces 6-Hour Mortality at the Critical Hemoglobin Concentration

2004 ◽  
Vol 100 (1) ◽  
pp. 70-76 ◽  
Author(s):  
Jens Meier ◽  
Gregor I. Kemming ◽  
Hille Kisch-Wedel ◽  
Stefan Wölkhammer ◽  
Oliver P. Habler
Keyword(s):  
Oxygen Supply ◽  
Oxygen Demand ◽  
Hemoglobin Concentration ◽  
Acute Normovolemic Hemodilution ◽  
Oxygen Fraction ◽  
Normovolemic Hemodilution ◽  
Fraction Of Inspired Oxygen ◽  
The Individual ◽  
Hyperoxic Ventilation ◽  
Adequate Tissue

Background Acute normovolemic hemodilution reduces the circulating erythrocyte mass and, thus, the hemoglobin concentration. After extreme acute normovolemic hemodilution to the critical hemoglobin concentration (Hbcrit), oxygen demand of the tissues is no longer met by oxygen supply, and death occurs with increasing oxygen debt. The aim of the current study was to investigate whether ventilation with 100% oxygen (fraction of inspired oxygen [FiO2] = 1.0; hyperoxic ventilation) initiated at Hbcrit could restore adequate tissue oxygenation and prevent death. Methods Fourteen anesthetized pigs ventilated with room air (FiO2 = 0.21) were hemodiluted by exchange of whole blood for 6% hydroxyethyl starch (200,000:0.5) until the individual Hbcrit was reached. Hbcrit was defined as the onset of oxygen supply dependency of oxygen consumption and was identified with indirect calorimetry. For the next 6 h, animals were either ventilated with an FiO2 of 0.21 (n = 7) or an FiO2 of 1.0 (n = 7). Results All animals in the 0.21 FiO2 group died within the first 3 h at Hbcrit (i.e., 6-h mortality 100%). Death was preceded by an increase of serum concentrations of lactate and catecholamines. In contrast to that, six of the seven animals of the 1.0 FiO2 group survived the complete 6-h observation period without lactacidosis and increased serum catecholamines (i.e., 6-h mortality 14%; FiO2 0.21 vs. FiO2 1.0, P < or = 0.05). After 6 h at Hbcrit, the FiO2 was reduced from 1.0 to 0.21, and five of the six animals died within the next 3 h. Conclusion In anesthetized pigs submitted to lethal anemia, hyperoxic ventilation enabled survival for 6 h without signs of circulatory failure.

Hemodilution and hyperoxia locally change distribution of regional pulmonary perfusion in dogs

1998 ◽  
Vol 274 (2) ◽  
pp. H520-H528 ◽  
Author(s):  
Martin Kleen ◽  
Oliver Habler ◽  
Jörg Hutter ◽  
Gregor Kemming ◽  
Armin Podtschaske ◽  
...  
Keyword(s):  
Pulmonary Blood Flow ◽  
Relative Dispersion ◽  
Acute Normovolemic Hemodilution ◽  
Vertical Location ◽  
Entire Lung ◽  
Volume Measurements ◽  
Anesthetized Dogs ◽  
Normovolemic Hemodilution ◽  
Hyperoxic Ventilation ◽  
Relationship Of

In seven anesthetized dogs, the effects of acute normovolemic hemodilution (ANH) to a hematocrit of 20 and 8% and the effects of hyperoxic ventilation (100% oxygen) on distribution of regional pulmonary blood flow (rPBF; radioactive microspheres) were investigated. Normovolemia was monitored with blood volume measurements (indocyanine green dilution kinetics). Before ANH, fractal dimension ( D) of rPBF in the whole lung was 1.19 ± 0.09 (mean ± SD). Spatial correlation (ρ) of rPBF in the whole lung was 0.6 ± 0.08. D is a resolution-independent measure for global rPBF distribution, and ρ is the averaged flow relationship of directly neighboring lung samples. With regard to the entire lung, neither ANH nor hyperoxia changed D or ρ. With regard to horizontal, isogravitational planes, ANH induced opposite changes of rPBF heterogeneity depending on the vertical location of the plane and the parameter used. In ventral planes, a change in relative dispersion (SD/mean) indicated decreased homogeneity. However, ρ suggested more homogeneous perfusion. Hyperoxia restored baseline rPBF distribution. Our data suggest that ANH causes different alterations of heterogeneity of rPBF depending on location within the lung.

scholarly journals Effect of High- and Low-molecular-weight Low-substituted Hydroxyethyl Starch on Blood Coagulation during Acute Normovolemic Hemodilution in Pigs

2006 ◽  
Vol 105 (6) ◽  
pp. 1228-1237 ◽  
Author(s):  
Caroline Thyes ◽  
Caveh Madjdpour ◽  
Philippe Frascarolo ◽  
Thierry Buclin ◽  
Marco Bürki ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Blood Coagulation ◽  
Plasma Concentrations ◽  
Hemoglobin Concentration ◽  
Low Molecular Weight ◽  
Acute Normovolemic Hemodilution ◽  
Regression Parameters ◽  
Angle Alpha ◽  
Normovolemic Hemodilution

Background Hydroxyethyl starches (HES) with lower impact on blood coagulation but longer intravascular persistence are of clinical interest. The current study aimed to investigate in vivo the isolated effect of molecular weight on blood coagulation during progressive acute normovolemic hemodilution. Methods Twenty-four pigs were normovolemically hemodiluted up to a total exchange of 50 ml . kg . body weight of HES 650/0.42 or HES 130/0.42. Serial blood sampling was performed to measure HES plasma concentration and to assess blood coagulation. Concentration-effect relations were analyzed by linear regression, followed by the Student t test on regression parameters. Results Blood coagulation was increasingly compromised toward hypocoagulability by acute normovolemic hemodilution with both treatments (P < 0.01). Significantly greater impact on activated partial thromboplastin time (P = 0.04) and significantly stronger decrease of maximal amplitude (P = 0.04), angle alpha (P = 0.02), and coagulation index (P = 0.02) was seen after acute normovolemic hemodilution with HES 650/0.42 as compared with HES 130/0.42. Except for factor VIII (P = 0.04), no significant differences between both treatments were observed when relating antihemostatic effects to HES plasma concentrations (P > 0.05). A significantly lesser decrease of hemoglobin concentration has been found with HES 650/0.42 as compared with HES 130/0.42 (P < 0.01) in relation to HES plasma concentrations. Conclusion High-molecular-weight HES (650/0.42) shows a moderately greater antihemostatic effect than low-molecular-weight HES (130/0.42) during acute normovolemic hemodilution. However, similar effects on hemostasis were observed with both treatments when observed antihemostatic effects were related to measured HES plasma concentrations. In addition, HES 650/0.42 may have a lower efficacy in immediately restoring plasma volume.

Acute decrease in renal microvascular Po2 during acute normovolemic hemodilution

2007 ◽  
Vol 292 (2) ◽  
pp. F796-F803 ◽  
Author(s):  
Tanja Johannes ◽  
Egbert G. Mik ◽  
Boris Nohé ◽  
Klaus E. Unertl ◽  
Can Ince
Keyword(s):  
Wistar Rats ◽  
Early Stage ◽  
Oxygen Demand ◽  
Renal Tissue ◽  
Acute Normovolemic Hemodilution ◽  
Organ Systems ◽  
Wide Range ◽  
Male Wistar Rats ◽  
Normovolemic Hemodilution ◽  
Microvascular Oxygenation

Large differences in the tolerance of organ systems to conditions of decreased O2 delivery such as hemodilution exist. The kidney receives ∼25% of the cardiac output and O2 delivery is in excess of the oxygen demand under normal circumstances. In a rat model of acute normovolemic hemodilution (ANH), we studied the effect of reduced hematocrit on renal regional and microvascular oxygenation. Experiments were performed in 12 anesthetized male Wistar rats. Six animals underwent four steps of ANH (hematocrit 25, 15, 10, and <10%). Six animals served as time-matched controls. Systemic and renal hemodynamic and oxygenation parameters were monitored. Renal cortical (c) and outer medullary (m) microvascular Po2 (μPo2) and the renal venous Po2 (PrvO2) were continuously measured by oxygen-dependent quenching of phosphorescence. Despite a significant increase in renal blood flow in the first two steps of ANH, cμPo2 and mμPo2 dropped immediately. From the first step onward oxygen consumption (V̇o2ren) became dependent on oxygen delivery (Do2ren). With a progressive decrease in hematocrit, a significant correlation between μPo2 and V̇o2ren could be observed, as well as a Po2 gap between μPo2 and PrvO2. Furthermore, there was a high correlation between V̇o2ren and RBF over a wide range of flows. In conclusion, the oxygen supply to the renal tissue is becoming critical already in an early stage of ANH due to the combination of increased V̇o2ren, decreased Do2ren, and intrarenal O2 shunt. This has clinical relevance as recent publications reporting that hemodilution during surgery forms a risk factor for postoperative renal dysfunction.

Intestinal and Cerebral Oxygenation during Severe Isovolemic Hemodilution and Subsequent Hyperoxic Ventilation in a Pig Model

2002 ◽  
Vol 97 (3) ◽  
pp. 660-670 ◽  
Author(s):  
Jasper van Bommel ◽  
Adrianus Trouwborst ◽  
Lothar Schwarte ◽  
Martin Siegemund ◽  
Can Ince ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Delivery ◽  
Oxygen Supply ◽  
Cerebral Oxygenation ◽  
Oxygen Extraction ◽  
Control Group ◽  
Isovolemic Hemodilution ◽  
Systemic Oxygen ◽  
Fraction Of Inspired Oxygen ◽  
Hyperoxic Ventilation

Background During severe isovolemic hemodilution, determination of critical hematocrit levels for the microvascular oxygenation of different organs might provide more insight into the effect of the redistribution of blood flow and oxygen delivery on the oxygenation of different organs. The effect of an increased amount of dissolved oxygen on tissue oxygenation during severely decreased hematocrit levels is not clear. Methods Fifteen anesthetized pigs were randomized between an experimental group (n = 10), in which severe isovolemic hemodilution was performed with 6% hydroxyethylstarch (1:1), and a time-matched control group (n = 5). Systemic, intestinal, and cerebral hemodynamic and oxygenation parameters were monitored. Microvascular oxygen partial pressure (muPo(2) ) was measured in the cerebral cortex and the intestinal serosa and mucosa, using the oxygen-dependent quenching of Pd-porphyrin phosphorescence. In the final phase of the experiment, fraction of inspired oxygen was increased to 1.0. Results Hemodilution decreased hematocrit from 25.3 +/- 3.0 to 7.6 +/- 1.2% (mean +/- SD). Systemic and intestinal oxygen delivery fell with the onset of hemodilution; intestinal oxygen consumption deceased at a hematocrit of 9.9%, whereas the systemic oxygen consumption decreased at a hematocrit of 7.6%. During hemodilution, the intestinal and cerebral oxygen extraction ratios increased from baseline with 130 and 52%, respectively. Based on the intersection of the two best-fit regression lines, determined by a least sum of squares technique, similar critical hematocrit levels were found for systemic oxygen consumption and the cerebral and intestinal mucosa muPo(2); the intestinal serosa muPo(2) decreased at an earlier stage (P &lt; 0.05). Hyperoxic ventilation improved the muPo(2) values but not systemic or intestinal oxygen consumption. Conclusions During isovolemic hemodilution, the diminished oxygen supply was redistributed in favor of organs with a lower capacity to increase oxygen extraction. It is hypothesized that redirection of the oxygen supply within the intestines resulted in the preservation of oxygen consumption and mucosal muPo(2) compared with serosal muPo(2).

Physiological and Hereditary Hyperbilirubinemia in Athletes: Role in Reducing Efficiency and Correction Methodology

2020 ◽  
Vol 5 (5) ◽  
pp. 386-393
Author(s):  
L. M. Gunina ◽  
◽  
Kazys Mylashyus ◽  
Voitenko V. L. ◽  
◽  
...  
Keyword(s):  
Physical Activity ◽  
Functional State ◽  
Oxygen Demand ◽  
Diagnostic Algorithm ◽  
Drug Prevention ◽  
The Body ◽  
Erythrocyte Membranes ◽  
Pharmacological Agents ◽  
Bilirubin Metabolism ◽  
The Individual

Under high-intensity loads, the athlete's bodies take place a number of biochemical reactions and physiological processes that can lead to hyperbilirubinemia. The factors that can initiate the onset of this phenomenon include the syndrome of micro-damage muscle, violation of the integrity of erythrocyte membranes, decreased blood pH, malnutrition and increase oxygen demand of the body. Degree of expression of manifestations of physiological bilirubinemia depends on the level of adaptation of the athlete to the physical activities offered. Hyperbilirubinemia in athletes can be one of the components of the deterioration of the functional state, forming the symptoms of endogenous intoxication. The relevance of this problem in sport lies in the relatively low detection rate of hyperbilirubinemia due to the lack of regular screening studies. However, in drawing up a plan of nutritional- metabolic support for training and competitive activity and recovery measures, must not only the individual reaction of the athlete body to physical activity, but also the severity of shifts in the indicators of bilirubin metabolism and their ratio. The article describes the reasons for the increase in bilirubin levels, which can be caused by both the effect of physical activity and by the presence of pathological processes in athletes. The factors influencing the blood serum’s bilirubin content are also highlighted, which include the state of erythrocyte cell membranes and the rate of hemoglobin destruction, the functional state of the liver, the specifics of physical loads and the use of ergogenic pharmacological agents by athletes. Particular accent has been placed on the illumination of hereditary hyperbilirubinemias, which may have been detected at the stage of selection of athletes. The most common phenomenon is Gilbert's syndrome, which occurs in 2-5% of cases in the general population, is characterized in the clinic by a benign flow and is manifested by episodes of jaundice and an increase in total bilirubin content to moderate values due to indirect. The frequency of detection of hyperbilirubinemias in the population of athletes is 4.68%, among which Gilbert's disease accounts for almost half (48.7%). Conclusion. The work highlighted the pathogenesis and diagnostic algorithm of Gilbert's disease, and also emphasized that its drug prevention and correction in athletes to maintain functional and physical fitness should be carried out taking into account anti-doping rules, which requires upon diagnosis timely receipt of a therapeutic exclusion

scholarly journals Effects of whole blood storage in a polyolefin blood bag on platelets for acute normovolemic hemodilution

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yutaka Murata ◽  
Eriko Kusudo ◽  
Shuji Kawamoto ◽  
Kazuhiko Fukuda
Keyword(s):  
Polyvinyl Chloride ◽  
Conventional Method ◽  
Whole Blood ◽  
Gas Permeability ◽  
Acute Normovolemic Hemodilution ◽  
Blood Storage ◽  
Cell Parameters ◽  
Storage Method ◽  
Normovolemic Hemodilution ◽  
Induced Aggregation

AbstractAcute normovolemic hemodilution (ANH) is a potential transfusion method for platelets, as well as for red blood cells. However, previous studies have shown that whole blood storage in ANH decreases platelet aggregability by 14.7–76.3% and that this decrease is not recovered by reinfusion. We investigated whether a new whole blood storage method for 6 h using a polyolefin bag, based on the platelet concentrates storage method, would maintain platelet function better than the conventional method using a polyvinyl chloride bag. We demonstrated that storage of whole blood in a polyolefin bag maintained ADP-induced aggregation rates at more than twofold higher than those in a polyvinyl chloride bag, and also significantly suppressed P-selectin expression, a platelet activation marker (ADP-induced aggregation rates: 24.6 ± 5.1% vs. 51.7 ± 11.5%, p = 0.002; P-selectin expression; 50.3 ± 8.4MFI vs. 31.6 ± 9.3MFI, p = 0.018). These results could be attributed to the high gas permeability of polyolefin, which lowered PCO2 and maintained a high pH with or without agitation. There were no significant changes in platelet count and red blood cell parameters due to the storage methods. Our results suggest that ANH using polyolefin bags is advantageous in improving hemostatic function compared to the conventional method.

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