Restoration Of Blood Volume Research Articles

In vivo optical imaging of revascularization after brain trauma in mice

Revascularization following brain trauma is crucial to the repair process. We used optical micro-angiography (OMAG) to study endogenous revascularization in living mice following brain injury. OMAG is a volumetric optical imaging method capable of in vivo mapping of localized blood perfusion within the scanned tissue beds down to capillary level imaging resolution. We demonstrated that OMAG can differentiate revascularization progression between traumatized mice with and without soluble epoxide hydrolase (sEH) gene deletion. The time course of revascularization was determined from serial imaging of the traumatic region in the same mice over a one-month period of rehabilitation. Restoration of blood volume at the lesion site was more pronounced in sEH knockout mice than in wild-type mice as determined by OMAG. These OMAG measurements were confirmed by histology and showed that the sEH knockout effect may be involved in enhancing revascularization. The correlation of OMAG with histology also suggests that OMAG is a useful imaging tool for real-time in vivo monitoring of post-traumatic revascularization and for evaluating agents that inhibit or promote endogenous revascularization during the recovery process in small rodents.

Bufalin Prevents Rrestoration of Blood Volume after Hemorrhage.

Shock is associated with cellular depolarization, a rise in extracellular K and intracellular Na, and a movement of water from the extracellular to the intracellular space. These phenomena can be explained by an inhibition of Na/K ATPase. We have found that plasma (extracts) from shocked rats inhibit Na/KATPase and increases water movement into cells. Recently, bufodienolides have been identified in mammalian plasma and are strong inhibitors of Na/K ATPase. To determine if Bufalin or Marinobufogenin (MBG) can prevent normal restoration of blood volume to mild hemorrhage, we treated awake Sprague‐Dawley rats, with either 1) 20ml/kg hemorrhage, 2) an infusion of Bufalin or MBG, or 3) both (n=>8 all groups). Hemorrhage led to an immediate fall in plasma volume followed by recovery to normal by 60min. However, rats given bufalin and non‐lethal hemorrhage failed to restore blood volume and died within 60min. Bufalin alone led to no significant change in blood volume. Marinobufogenin, given at this dose and higher did not prevent restoration of blood volume. These data suggest that Bufalin but not MBG, prevents normal restoration of blood volume after hemorrhage.

Código rojo: guía para el manejo de la hemorragia obstétrica

La hemorragia obstétrica es la primera causa de muerte materna en el mundo. Lo mismo ocurre en el departamento de Antioquia, Colombia. Por ser una situación urgente y que compromete la vida de las mujeres, se presenta la siguiente guía de manejo para el tratamiento del choque hemorrágico de origen obstétrico, basada en los siguientes principios básicos: el manejo óptimo del tiempo, la reposición adecuada del volumen sanguíneo, el trabajo en equipo y la insistencia en el uso de las diferentes maniobras para la disminución de la hemorragia.

Gastrointestinal Hemorrhage: Should We Transfuse Less?

Although blood transfusion has an established place in the conventional management of acute upper gastrointestinal (GI) hemorrhage, there is growing evidence of adverse side effects of transfusion, both acute and later. An Ovid Medline literature search was performed to evaluate the significance and importance of these effects. Evidence of impaired hemostasis with repletion of blood volume in the acute phase was found in multiple studies and in uncontrolled studies in combat casualties. There are multiple large studies of a so-called immunosuppressive effect of transfused blood leading to increased infection rates and mortality dependent both on dose and on the age of the stored blood. In view of evidence of increased bleeding with early blood volume restoration and the growing evidence of so-called immunosuppressive effects of stored blood, there is a need to consider trials using a conservative utilization of blood in acute GI bleeding.

Surgical Patients\' Knowledge and Acceptance of Autologous Blood Transfusion.

Background: Homologous blood transfusion carries a well-documented array of risks especially in an HIV endemic environment like Nigeria. It is therefore imperative to consider other forms of restoring blood volume in surgical patients. Autologous blood transfusion (ABT) is one of the ways the problem of HIV transmission can be reduced among surgical patients. The knowledge and acceptability of ABT among surgical patients about ABT, especially pre-donated ABT were assessed. It also assessed whether or not surgeons inform elective surgical patients about this alternative Materials And Methods Questionnaires were distributed among elective surgical patients that presented during the study period. The knowledge, willingness and the factors influencing the willingness of the patients to participate in ABT were investigated. The data were analyzed with SPSS Version10. Results Of the 116 patients [71 males; 45 females] interviewed, 29 (25.0 %) had heard about ABT, 80 (69.0 %) patients had never heard about ABT while 7 (6.1 %) were not sure. Of the 29 respondents who had heard about ABT, only 2 had had ABT. Of the 48 patients who needed blood for current surgical problems, only 4 (9.3 %) would have ABT. There was a significant difference in the number of respondents who believed that ABT is better than homologous transfusion (x2 = 69.11, p < 0.001). Conclusion The knowledge of ABT is low among our surgical patients and surgeons should present this alternative to their patients. The acceptance of ABT may also help in reducing or eliminating HIV transmission via blood transfusion. Keywords: homologous, hepatitis, surgical procedures, blood volume.Sudan Journal of Medical Sciences Vol. 3 (2) 2008: pp. 109-114

Position of the New Zealand Dietetic Association (Inc): Nutrition for exercise and sport in New Zealand

Position of the New Zealand Dietetic Association (Inc): Nutrition for exercise and sport in New Zealand

Massive transfusion and nonsurgical hemostatic agents

Hemorrhage in trauma is a significant challenge, accounting for 30% to 40% of all fatalities, second only to central nervous system injury as a cause of death. However, hemorrhagic death is the leading preventable cause of mortality in combat casualties and typically occurs within 6 to 24 hrs of injury. In cases of severe hemorrhage, massive transfusion may be required to replace more than the entire blood volume. Early prediction of massive transfusion requirements, using clinical and laboratory parameters, combined with aggressive management of hemorrhage by surgical and nonsurgical means, has significant potential to reduce early mortality. Although the classification of massive transfusion varies, the most frequently used definition is ten or more units of blood in 24 hrs. Transfusion of red blood cells is intended to restore blood volume, tissue perfusion, and oxygen-carrying capacity; platelets, plasma, and cryoprecipitate are intended to facilitate hemostasis through prevention or treatment of coagulopathy. Massive transfusion is uncommon in civilian trauma, occurring in only 1% to 3% of trauma admissions. As a result of a higher proportion of penetrating injury in combat casualties, it has occurred in approximately 8% of Operation Iraqi Freedom admissions and in as many as 16% during the Vietnam conflict. Despite its potential to reduce early mortality, massive transfusion is not without risk. It requires extensive blood-banking resources and is associated with high mortality. This review describes the clinical problems associated with massive transfusion and surveys the nonsurgical management of hemorrhage, including transfusion of blood products, use of hemostatic bandages/agents, and treatment with hemostatic medications.

How to Evaluate Blood Substitutes for Endothelial Cell Toxicity

The most common and widely transplanted tissue worldwide is blood. But concerns about safety and adequacy of blood transfusion have fostered 20 years of research into blood substitutes such as oxygen carriers based on modified hemoglobin (Hb). Chemically modified or genetically engineered Hb developed as oxygen therapeutics are designed to restore blood volume and to correct oxygen deficit due to ischemia in a variety of clinical settings. Uncontrolled oxidative reactions mediated by large amounts of cell-free Hb and their reactions with various oxidant/antioxidant and cell signalling systems emerge as an important pathway of toxicity. Hemoglobin can react with oxygen and NO, leading to the production of reactive oxygen or nitrogen species. Inside the bloodstream, oxidized Hb and ROS/RNS are in direct contact with endothelial cells (EC). Thus, chain reactions may trigger molecular and cellular biology, causing oxidative stress-related pathologies. This editorial presents an overview of interactions between Hb (modified or not) and EC. We also propose a wide range of techniques and methods to assess oxidative stress and inflammation responses of EC after exposure to Hb. This editorial can serve as a guide to evaluate in vitro toxicity of new Hb molecules.

Prevention of Orthostatic Intolerance after Exposure to Microgravity: Exercise Countermeasure and Volume Loading

Prolonged exposure to microgravity leads to hypovolemia and cardiac atrophy, both of which contribute to orthostatic intolerance on return to earth. We hypothesized that an exercise countermeasure (90 min/day, 75% max HR) would prevent the cardiac atrophy after exposure to simulated microgravity (6 degree head‐down bed rest) while an exercise countermeasure with volume loading at the end of bed rest (up to pre‐bed rest blood volume and left ventricular (LV) filling pressure) would preserve the orthostatic tolerance. To test these hypotheses subjects were randomly assigned into three groups (N=7 in each group): exercise group (Ex), Dextran infusion group (Dx) and exercise plus Dextran infusion group (Ex+Dx). Cardiac remodeling was evaluated by LV muscle mass with MRI and pressure‐volume relationship of LV. Orthostatic tolerance was evaluated by a max LBNP test. Measurements were made pre and post 2‐wk bed rest. LV mass increased by 5% and pressure‐volume curves were similar after bed rest in both Ex and Ex+Dx, while a decrease of LV mass by 4% and left‐ward shift of the pressure‐volume curve were observed in Dx alone. Orthostatic tolerance was only maintained in Ex+Dx after bed rest, which decreased in EX alone by 42% and in Dx alone by 25%. Preserved LV morphology with restoration of normal blood volume appears to be necessary to prevent orthostatic intolerance after exposure to microgravity. Supported by NSBRI

Central venous catheterization—An anatomical review of a clinical skill, Part 2: Internal jugular vein via the supraclavicular approach

The safe and successful performance of a central venous catheterization (CVC) requires a specific knowledge of anatomy in addition to a working knowledge. Misunderstanding the anatomy may result in failure or complications. This review aims to aid understanding of the anatomical framework, pitfalls, and complications of CVC of the internal jugular veins. CVC is common practice amongst surgeons, anesthesiologists, and emergency room physicians during the preparations for major surgical procedures such as open-heart surgery, as well as for intensive care monitoring and rapid restoration of blood volume. Associated with this technique are certain anatomical pitfalls and complications that can be successfully avoided if one possesses a thorough knowledge of the contraindications, regional anatomy, and rationale of the technique.

Central venous catheterization—An anatomical review of a clinical skill—Part 1: Subclavian vein via the infraclavicular approach

The safe and successful performance of a central venous catheterization (CVC) requires a specific knowledge of anatomy in addition to a working knowledge. Misunderstanding the anatomy may result in failure or complications. This review aims to aid understanding of the anatomical framework, pitfalls, and complications of CVC of the subclavian (SCV). CVC is common practice amongst surgeons, anesthesiologists, and emergency room physicians during the preparations for major surgical procedures such as open-heart surgery, as well as, for intensive care monitoring and rapid restoration of blood volume. Associated with this technique are certain anatomical pitfalls and complications that can be successfully avoided if one possesses a thorough knowledge of the contraindications, regional anatomy, and rationale of the technique.

The Auto‐Digestion Hypothesis: Blockade of Pancreatic Digestive Enzymes in the Lumen of the Intestine during Hemorrhagic Shock Reduces Mortality.

Our evidence shows that pancreatic digestive enzyme blockade in the intestinal lumen reduces levels of inflammatory mediators in portal veins and central circulation with reduced peripheral inflammation, tissue swelling, and multi-organ dysfunction. No study exists to examine whether blockade of the digestive enzymes in the lumen of the intestine during acute hemorrhagic shock leads to long-term survival. Thus we exposed mature male Wistar rats to hemorrhagic shock (mean arterial pressure reduced from ~110 to 30 – 35 mmHg for 120 min) followed by full restoration of shed blood volume (0.5 U/ml heparin). Control animals were administered at 60 min GoLytely® by direct injection (15 ml) into the lumen of the duodenum, ileum and secum. Treated animals received at 60 min or prior at the time of pressure decompensation (between 40 and 60 min) GoLytely supplemented with the pancreatic enzyme inhibitor ANGD (PNAS, 97:, 2000; 0.1 mM; 15 ml). Survival was recorded for 2 weeks until normal weight gain. Without blockade of digestive enzymes 8/9 rats died within the first 12 hours, while with blockade 8/10 rats survived. Digestive enzymes blockade at a later stage of hemorrhagic shock yields reduced survival. These results show a dramatic reduction of mortality in hemorrhagic shock induced multi-organ failure with possible clinical utility. Supported in part by HL 67825.

Sodium depletion activates the aldosterone-sensitive neurons in the NTS independently of thirst

Thirst and sodium appetite are both critical for restoring blood volume. Because these two behavioral drives can arise under similar physiological conditions, some of the brain sensory sites that stimulate thirst may also drive sodium appetite. However, the physiological and temporal dynamics of these two appetites exhibit clear differences, suggesting that they involve separate brain circuits. Unlike thirst-associated sensory neurons in the hypothalamus, the 11-beta-hydroxysteroid dehydrogenase type 2 (HSD2) neurons in the rat nucleus tractus solitarius (NTS) are activated in close association with sodium appetite (16). Here, we tested whether the HSD2 neurons are also activated in response to either of the two physiological stimuli for thirst: hyperosmolarity and hypovolemia. Hyperosmolarity, produced by intraperitoneal injection of hypertonic saline, stimulated a large increase in water intake and a substantial increase in immunoreactivity for the neuronal activity marker c-Fos within the medial NTS, but not in the HSD2 neurons. Hypovolemia, produced by subcutaneous injection of hyperoncotic polyethylene glycol (PEG), stimulated an increase in water intake within 1-4 h without elevating c-Fos expression in the HSD2 neurons. The HSD2 neurons were, however, activated by prolonged hypovolemia, which also stimulated sodium appetite. Twelve hours after PEG was injected in rats that had been sodium deprived for 4 days, the HSD2 neurons showed a consistent increase in c-Fos immunoreactivity. In summary, the HSD2 neurons are activated specifically in association with sodium appetite and appear not to function in thirst.

Human albumin solution for resuscitation and volume expansion in critically ill patients

Human albumin solutions are used in a range of medical and surgical problems. Licensed indications are the emergency treatment of shock and other conditions where restoration of blood volume is urgent, burns, and hypoproteinaemia. Human albumin solutions are more expensive than other colloids and crystalloids. To quantify the effect on mortality of human albumin and plasma protein fraction (PPF) administration in the management of critically ill patients. We searched the Cochrane Injuries Group trials register, Cochrane Central Register of Controlled Trials, Medline, Embase and BIDS Index to Scientific and Technical Reference lists of trials and review articles were checked, and authors of identified trials were contacted. The search was last updated in August 2004. Randomised controlled trials comparing albumin/PPF with no albumin/PPF, or with a crystalloid solution, in critically ill patients with hypovolaemia, burns or hypoalbuminaemia. We collected data on the participants, albumin solution used, mortality at the end of follow up, and quality of allocation concealment. Analysis was stratified according to patient type. We found 32 trials meeting the inclusion criteria and reporting death as an outcome. There were 1632 deaths among 8452 trial participants. For hypovolaemia, the relative risk of death following albumin administration was 1.01 (95% confidence interval 0.92-1.10). This estimate was heavily influenced by the results of the SAFE trial, which contributed 91% of the information (based on the weights in the meta-analysis). For burns, the relative risk was 2.40 (1.11-5.19) and for hypoalbuminaemia the relative risk was 1.38 (0.94-2.03). There was no substantial heterogeneity between the trials in the various categories (chi2 = 21.86, df = 25, p = 0.64). The pooled relative risk of death with albumin administration was 1.04 (0.95-1.13). For patients with hypovolaemia there is no evidence that albumin reduces mortality when compared with cheaper alternatives such as saline. There is no evidence that albumin reduces mortality in critically ill patients with burns and hypoalbuminaemia. The possibility that there may be highly selected populations of critically ill patients in which albumin may be indicated remains open to question. However, in view of the absence of evidence of a mortality benefit from albumin and the increased cost of albumin compared to alternatives such as saline, it would seem reasonable that albumin should only be used within the context of well concealed and adequately powered randomised controlled trial. There is no evidence that giving human albumin to replace lost blood in critically ill or injured people improves survival when compared to giving saline. Trauma, burns or surgery can cause people to lose large amounts of blood. Fluid replacement, giving fluids intravenously (into a vein), is used to help restore blood volume and hopefully reduce the risk of dying. Blood products (including human albumin), non-blood products or combinations can be used. The review of trials found no evidence that albumin reduces the risk of dying. Albumin is very expensive in which case it may be better to use cheaper alternatives such as saline for fluid resuscitation.

Personal view: crystalloid transfusion in acute gastrointestinal haemorrhage: is it beneficial? An historical perspective

The conventional management of acute gastrointestinal haemorrhage mandates early repletion of blood volume with crystalloids and blood, as part of the initial management, where there is evidence of hypovolaemia. Meanwhile there is a major trend towards a restrained use of fluid to raise blood pressure to near normal for the bleeding patient in trauma and similar emergencies. This divergence of view requires analysis. An Ovid/MEDLINE, Google and extensive literature search focused on the resuscitation and transfusion of bleeding trauma patients was performed. In addition to clear evidence from animal experiments that early restoration of blood volume perpetuates bleeding, there is considerable evidence in humans - both in war and civilian life - that rapid crystalloid infusion is harmful. I also report a personal series of benefit from restricted transfusion in acute upper gastrointestinal haemorrhage in humans. Given the lack of evidence of benefit for rapid blood volume repletion in acute gastrointestinal haemorrhage, there is need for controlled studies of the most appropriate approach to crystalloid transfusion in acute gastrointestinal bleeding.

Successful Use of Recombinant Factor VIIa for Treatment of Severe Postpartum Hemorrhage

1postpartum blood loss still results in severe maternal morbidity, 2 such as hypovolemic shock, renal failure, adult respiratory distress syndrome, hepatic failure, and disseminated intravascular coagulopathy. 3 Early, effective, and preferably noninvasive treatment is therefore essential. Primary postpartum hemorrhage is initially managed by restoration of blood volume, administration of oxytocin and prostaglandins, and the correction of coagulation. 2 If these initial conservative therapeutic measures do not control the bleeding, more drastic and invasive interventions such as bilateral artery ligation, angiography with selective embolization, or, as a last resort, hysterectomy can be performed. Recombinant factor VIIa (rFVIIa; NovoSeven) is a safe and effective drug for the treatment of bleeding episodes in patients with inherited or acquired hemophilia A or B and antibodies to the relevant coagulation factor (VIII or IX, respectively). Recently rFVIIa has been used successfully in patients with congenital or acquired platelet disorders, thrombocytopenia, and severe von Willebrand’s disease (type 3). The use of rFVIIa in patients with severe bleeding without known coagulation factor deficiencies or (preexisting) bleeding disorders has been reported in several case reports. 4-7 We describe a case of severe postpartum hemorrhage due to uterine atony resistant to conservative treatment in which use of a single dose of rFVIIa successfully controlled the bleeding and thereby obviated invasive procedures.

Haemodynamic response to acute hypovolaemia, rapid blood volume expansion and adrenaline administration in an infant animal model

We performed a prospective experimental animal study in seven sedated and mechanically ventilated piglets weighing 9+/-0.8 kg, to assess the haemodynamic response to acute hypovolaemia, rapid blood volume expansion and adrenaline (epinephrine) administration in an infant animal model. Withdrawal of 20 mL/kg of blood (hypovolaemia), rapid infusion of 20 mL/kg of blood (expansion) and the administration of 0.01 mg/kg of adrenaline were made in each animal. Heart rate, mean blood pressure (MBP), central venous pressure (CVP), pulmonary capillary pressure (PCP), cardiac index (CI), systemic vascular resistance index (SVRI), left ventricular contractility (Dp/dtmax), blood volume variables, including intrathoracic blood volume index (ITBI), global end-diastolic volume (GEDVI) and extravascular lung water index (ELWI). Hypovolaemia produced a significant decrease in the pressure, volume and CI variables, with an increase in SVRI and a decrease in Dp/dtmax. After expansion, all variables returned towards normal, with persistence of the SVRI increase and Dp/dtmax decrease. Changes in the blood volume variables (ITBI and GEDVI) were larger than in the pressure variables (CVP, PCP) in the case of both hypovolaemia and expansion. Adrenaline caused a slight increase in heart rate, MBP, CVP, PCP and Dp/dtmax with a greater increase in SVRI. None of the interventions led to changes in ELWI. We conclude that acute hypovolaemia produces an increase in SVRI and a decrease in Dp/dtmax that does not return fully to normal with restoration of blood volume. ITBI and GEDVI are more sensitive to changes in blood volume than CVP and PCP. Rapid blood volume expansion and adrenaline administration do not affect extravascular lung water.

Sequential patterns of haemodynamic and metabolic changes in experimental hypovolaemic shock. II. Responses to reinfusion of shed blood.

The haemodynamic and metabolic effects which follow the infusion of blood in experimental hypovolaemia have not been studied in detail. The 10 dogs that survived 90 min of hypovolaemia in a study of bleeding (Pardy and Dudley, 1979) were investigated during and shortly after the reinfusion of shed blood using the same techniques. Data from 9 animals were suitable for analysis. As with bleeding, 6 sequential phases were identified; reinfusion of blood was completed in the fifth phase. Initial reinfusion was associated with a rapid improvement in haemodynamic and metabolic status, although mean arterial pH fell because carbon dioxide production increased. Maximum metabolically effective tissue perfusion was probably attained in phase II, but haemodynamic improvement continued until phase IV. Arterial pH did not rise above the pre-infusion value until phase V, and this rise was the result of a fall in PaCO2 secondary to a reduction in physiological dead space and an increase in buffering capacity. Pulmonary artery pressure was superior to systemic artery pressure as a predictor of cardiac output during blood volume restoration. A number of conclusions pertaining to clinical practice are drawn.

Sheehan's Syndrome Presenting with Early Postpartum Congestive Heart Failure

We report the case of a young woman with Sheehan's syndrome who presented with ventricular arrhythmia and congestive heart failure. The patient was admitted because of postpartum hemorrhage and hypovolemic shock; a massive blood transfusion was required to restore blood volume. After initial stabilization, the patient developed acute respiratory distress and congestive heart failure accompanied by hemodynamic instability 2 weeks after delivery. Episodes of ventricular tachycardia of the torsade de pointes type and a prolonged QT interval were noted on baseline electrocardiogram. A low cortisol level was found incidentally, which led to the suspicion of hypopituitarism. The diagnosis was later supported by laboratory findings of multiple pituitary hormone deficiencies. After administration of corticosteroids and thyroxine, the patient's clinical condition improved dramatically. A pituitary magnetic resonance imaging scan 32 days after delivery revealed a diminished and flattened pituitary gland with prominent intrasellar cerebrospinal fluid loculation, which was compatible with the clinical diagnosis of empty sella with panhypopituitarism. The syndrome of acute anterior pituitary necrosis secondary to postpartum hemorrhage and shock was first described by Sheehan in 1939. Although the occurrence of Sheehan's syndrome is now rare, it should still be considered in any woman with a history of peripartum hemorrhage who develops manifestations of pituitary hormone deficiency. Appropriate hormone replacement therapy is essential and always results in dramatic clinical improvement.

Heterogeneity and oxidation status of commercial human albumin preparations in clinical use*

Human serum albumin is indicated for the treatment of shock, acute restoration of blood volume, and in hypoalbuminemia. Conflicting reports are found in the literature for the clinical safety and efficacy of human serum albumin administration to critically ill patients. We sought to analyze various commercially available albumin preparations for common, posttranslational modifications. Analysis of six commercially available albumin preparations for clinical use. Trauma research laboratory. Commercially available human serum albumin preparations and healthy volunteers. Six commercially available human serum albumin preparations were analyzed by high-performance liquid chromatography. The presence of various posttranslational modifications was identified by positive electrospray ionization, time-of-flight mass spectrometry. Three different lots from three preparations were also analyzed to assess variability within lots from the same manufacturer. Also, for the purpose of comparison, human serum albumin was analyzed in the plasma of healthy volunteers. The six human serum albumin preparations analyzed contained a high percentage (57.2 +/- 3.3%) of bound Cys34 (oxidation of cysteine in position 34 on the human serum albumin molecule) in comparison to the plasma human serum albumin from healthy volunteers (22.9 +/- 4.8%). Lot-to-lot variability in native human serum albumin ranged between 4.8% and 11.2% in three separate commercial albumins. Significant differences existed among the various commercial preparations in other posttranslational modifications of albumin. Human serum albumin species with a bound Cys34 account for a large percentage of the composition of human serum albumin preparations used for the treatment of critically ill patients. Also, the variability within lots from the same manufacturer is significant. Consequences of the administration of these oxidized forms of human serum albumin to critically ill patients warrants further investigation.