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Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite current recommendations on the management of pre-operative anaemia, there is no pragmatic guidance for the diagnosis and management of anaemia and iron deficiency in surgical patients. A number of experienced researchers and clinicians took part in an expert workshop and developed the following consensus statement. After presentation of our own research data and local policies and procedures, appropriate relevant literature was reviewed and discussed. We developed a series of best-practice and evidence-based statements to advise on patient care with respect to anaemia and iron deficiency in the peri-operative period. These statements include: a diagnostic approach for anaemia and iron deficiency in surgical patients; identification of patients appropriate for treatment; and advice on practical management and follow-up. We urge anaesthetists and peri-operative physicians to embrace these recommendations, and hospital administrators to enable implementation of these concepts by allocating adequate resources. [ABSTRACT FROM AUTHOR]

Oxygen (O(2)) is the most frequently used pharmaceutical in anesthesiology and intensive care medicine: Every patient receives O(2) during surgery or during a stay in the intensive care unit. Hypoxia and hypoxemia of various origins are the most typical indications which are mentioned in the prescribing information of O(2): the goal of the administration of O(2) is either an increase of arterial O(2) partial pressure in order to treat hypoxia, or an increase of arterial O(2) content in order to treat hypoxemia. Most of the indications for O(2) administration were developed in former times and have seldom been questioned from that time on as the short-term side-effects of O(2) are usually considered to be of minor importance. As a consequence only a small number of controlled randomized studies exist, which can demonstrate the efficacy of O(2) in terms of evidence-based medicine. However, there is an emerging body of evidence that specific side-effects of O(2) result in a deterioration of the microcirculation. The administration of O(2) induces arteriolar constriction which will initiate a decline of regional O(2) delivery and subsequently a decline of tissue oxygenation. The aim of the manuscript presented is to discuss the significance of O(2) as a pharmaceutical in the clinical setting. [ABSTRACT FROM AUTHOR]

The religious organization of Jehovah's Witnesses numbers more than 7 million members worldwide, including 165,000 members in Germany. Although Jehovah's Witnesses strictly refuse the transfusion of allogeneic red blood cells, platelets and plasma, Jehovah's Witness patients may nevertheless benefit from modern therapeutic concepts including major surgical procedures without facing an excessive risk of death. The present review describes the perioperative management of surgical Jehovah's Witness patients aiming to prevent fatal anemia and coagulopathy. The cornerstones of this concept are 1) education of the patient about blood conservation techniques generally accepted by Jehovah's Witnesses, 2) preoperative optimization of the cardiopulmonary status and correction of preoperative anemia and coagulopathy, 3) perioperative collection of autologous blood, 4) minimization of perioperative blood loss and 5) utilization of the organism's natural anemia tolerance and its acute accentuation in the case of life-threatening anemia. [ABSTRACT FROM AUTHOR]

Background: During acellular replacement of an acute blood loss, hyperoxic ventilation (HV) increases the amount of O2 physically dissolved in the plasma and thereby improves O2 supply to the tissues. While this effect could be demonstrated for HV with inspiratory O2 fraction (FiO2) 0.6, it was unclear whether HV with pure oxygen (FiO2 1.0) would have an additional effect on the physiological limit of acute normovolemic anemia. Methods: Seven anesthetized domestic pigs were ventilated with FiO2 1.0 and subjected to an isovolemic hemodilution protocol. Blood was drawn and replaced by a 6% hydroxyethyl starch (HES) solution (130/0.4) until a sudden decrease of total body O2 consumption (VO2) indicated the onset of O2 supply dependency (primary endpoint). The corresponding hemoglobin (Hb) concentration was defined as 'critical Hb' (Hbcrit). Secondary endpoints were parameters of myocardial function, central hemodynamics, O2 transport and tissue oxygenation. Results: HV with FiO2 1.0 enabled a large blood-for-HES exchange (156 ± 28% of the circulating blood volume) until Hbcrit was met at 1.3 ± 0.3 g/dl. After termination of the hemodilution protocol, the contribution of O2 physically dissolved in the plasma to O2 delivery and VO2 had significantly increased from 11.7 ± 2 to 44.2 ± 9.7% and from 29.1 ± 4.2 to 66.2 ± 11.7%, respectively. However, at Hbcrit, cardiovascular performance was found to have severely deteriorated. Conclusion: HV with FiO2 1.0 maintains O2 supply to tissues during extensive blood-for-HES exchange. In acute situations, where profound anemia must be tolerated (e.g. bridging an acute blood loss until red blood cells become available for transfusion), O2 physically dissolved in the plasma becomes an essential source of oxygen. However, compromised cardiovascular performance might require additional treatment. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The patient's individual anemia tolerance is pivotal when blood transfusions become necessary, but are not feasible for some reason. To date, the effects of neuromuscular blockade (NMB) on anemia tolerance have not been investigated. Methods: 14 anesthetized and mechanically ventilated pigs were randomly assigned to the Roc group (3.78 mg/kg rocuronium bromide followed by continuous infusion of 1 mg/kg/min, n = 7) or to the Sal group (administration of the corresponding volume of normal saline, n = 7). Subsequently, acute normovolemic anemia was induced by simultaneous exchange of whole blood for a 6% hydroxyethyl starch solution (130/0.4) until a sudden decrease of total body O2 consumption (VO2) indicated a critical limitation of O2 transport capacity. The Hb concentration quantified at this time point (Hbcrit) was the primary endpoint of the protocol. Secondary endpoints were parameters of hemodynamics, O2 transport and tissue oxygenation. Results: Hbcrit was significantly lower in the Roc group (2.4 ± 0.5 vs. 3.2 ± 0.7 g/dl) reflecting increased anemia tolerance. NMB with rocuronium bromide reduced skeletal muscular VO2 and total body O2 extraction rate. As the cardiac index increased simultaneously, total body VO2 only decreased marginally in the Roc group (change of VO2 relative to baseline -1.7 ± 0.8 vs. 3.2 ± 1.9% in the Sal group, p < 0.05). Conclusion: Deep NMB with rocuronium bromide increases the tolerance of acute normovolemic anemia. The underlying mechanism most likely involves a reduction of skeletal muscular VO2. During acellular treatment of an acute blood loss, NMB might play an adjuvant role in situations where profound stages of normovolemic anemia have to be tolerated (e.g. bridging an unexpected blood loss until blood products become available for transfusion). Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The expected cost explosion in transfusion medicine increases the socio-economic significance of specific institutional transfusion programs. In this context the estimated use of the patient's physiologic tolerance represents an integral part of any blood conservation concept. The present article summarizes the mechanisms, influencing factors and limits of this natural tolerance to anemia and deduces the indication for perioperative red blood cell transfusion. The current recommendations coincide to the effect that perioperative transfusion is unnecessary up to a Hb concentration of 10 g/dl (6.21 mmol/l) even in older patients with cardiopulmonary comorbidity and is only recommended in cases of Hb <6 g/dl (<3.72 mmol/l) in otherwise healthy subjects including pregnant women and children. Critically ill patients with multiple trauma and sepsis do not seem to benefit from transfusions up to Hb concentrations >9 g/dl (>5.59 mmol/l). In cases of massive hemorrhaging and diffuse bleeding disorders the maintenance of a Hb concentration of 10 g/dl (6.21 mmol/l) seems to contribute to stabilization of coagulation. [ABSTRACT FROM AUTHOR]

Copyright of Der Urologe A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The expected cost-explosion in transfusion medicine (increasing imbalance between donors and recipients, treatment of transfusion-associated complications) increases the socio-economic significance of the development of safe and effective synthetic oxygen carriers as an alternative to the transfusion of allogeneic red blood cells. Currently two types of artificial oxygen carriers have been tested for safety and efficacy in cases of severe anemia otherwise requiring transfusion. Solutions based on human or bovine hemoglobin (HBOC) possess vasoconstrictor properties in addition to their oxygen transport capacity. The impact of vasoconstriction on tissue perfusion and organ function is however not yet fully understood. Nevertheless, in 2001 the bovine HBOC Hemopure was approved in South Africa for treatment of acutely anemic surgical patients. The purely synthetic perfluorocarbon (PFC) emulsions increase the physically dissolved portion of arterial oxygen content. Due to their particulate nature (emulsion droplets) PFCs may only be infused in low doses to avoid overload and malfunction of phagocytic cells of the reticulo-endothelial system. As part of a multimodal blood conservation program (including normovolemic hemodilution and hyperoxia) the low-dose administration of Oxygent effectively increases intraoperative anemia tolerance. Although reduction of perioperative allogeneic blood transfusion has already been demonstrated for HBOC and PFC, the global clinical establishment of artificial oxygen carriers is not to be expected in the near future. [ABSTRACT FROM AUTHOR]

Fluid resuscitation from hemorrhagic shock is intended to abolish microcirculatory disorders and to restore adequate tissue oxygenation. Diaspirin cross-linked hemoglobin (DCLHb) is a hemoglobin-based oxygen carrier (HBOC) with vasoconstrictive properties. Therefore, fluid resuscitation from severe hemorrhagic shock using DCLHb was expected to improve perfusion pressure and tissue perfusion of kidneys and pancreas.In 20 anesthetized domestic pigs with an experimentally induced coronary stenosis, shock (mean arterial pressure 45 mmHg) was induced by controlled withdrawal of blood and maintained for 60 min. Fluid resuscitation (replacement of the plasma volume withdrawn during hemorrhage) was performed with either 10% DCLHb (DCLHb group,n = 10) or 8% human serum albumin (HSA) oncotically matched to DCLHb (HSA group,n = 10). Completion of resuscitation was followed by a 60-min observation period. Regional blood flow to the kidneys and the pancreas was measured by use of the radioactive microspheres method at baseline, after shock and 60 min after fluid resuscitation.All animals (10/10) resuscitated with DCLHb survived the 60-min observation period, while 5/10 control animals died within 20 min due to persisting subendocardial ischemia. In contrast to HSA survivors, pancreas and kidneys of DCLHb-treated animals revealed lower total and regional organ perfusion and regional oxygen delivery. Renal and pancreatic blood flow heterogeneity was higher in the DCLHb group.DCLHb-induced vasoconstriction afforded superior myocardial perfusion, but impaired regional perfusion of the kidneys and the pancreas. [ABSTRACT FROM AUTHOR]

Hemodilution reduces hematocrit (Hct) and blood oxygen content. Tissue oxygenation is mainly preserved by increased cardiac output. As myocardial O2-demands increase, coronary vasodilatation becomes necessary to increase myocardial blood flow. Myocardial ischemia occurs at a critical Hct-value (Hctcrit), with accompanying exhaustion of coronary reserve. Hyperoxic ventilation is known to both reverse peripheral tissue hypoxia at Hctcrit and also to induce coronary vasoconstriction. This study aimed to determine whether hyperoxic ventilation at Hctcrit further exacerbates myocardial ischemia and dysfunction. Nine anesthetized pigs ventilated on room air were hemodiluted by 1 : 1 exchange of blood with pentastarch (6%HES) to Hctcrit , defined as onset of myocardial ischemia (ECG changes). At Hctcrit , hyperoxic ventilation was started. Measurements were performed at baseline, at Hctcrit, and after 15 min of hyperoxic ventilation. We determined myocardial blood flow (microsphere method), arterial O2-content, subendocardial O2-delivery and myocardial function (left ventricular pressure increase). At Hctcrit 7 (6;8)%, O2-content was reduced [3.7 (3.1;3.9) ml dl−1]. Despite a compensatory increase of myocardial blood flow [531 (449;573), ml min−1100 g−1], all pigs displayed myocardial ischemia and compromised myocardial function ( P < 0.05). Hyperoxic ventilation produced increased coronary vascular resistance secondary to vasoconstriction, and reduced myocardial blood flow [426 (404;464), ml min−1100 g−1; P < 0.05]. Myocardial oxygenation was found to be maintained by increased O2-content [4.4 (4.2;4.8), ml dl−1; P < 0.05], the contribution of dissolved O2 to subendocardial O2-delivery increased (32 vs. 8%; P < 0.05), which preserved myocardial function. Hyperoxic ventilation at Hctcrit is followed by coronary vasoconstriction and reduction of coronary blood flow. However, myocardial oxygenation and function is maintained, as increased O2-content (in particular dissolved O2) preserves myocardial oxygenation. [ABSTRACT FROM AUTHOR]

Copyright of HNO is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The blood volume that has to be exchanged for crystalloids and/or colloids during acute normovolemic hemodilution (ANH) in order to reach a preset target hemoglobin concentration (hb) is usually predicted by the Bourke and Smith formula developed in 1974. This formula systematically overestimates the 'true' exchangeable blood volume (EBV), a fact that may potentially endanger patients because the target hb will be missed and the normovolemic anemia might turn out to be more severe than a priori intended. Our objective was to develop a more accurate mathematical model of hemodilution kinetics and to validate this new model in animals and in patients undergoing ANH.Methods: Twenty-two anesthetized beagle dogs and 18 patients under balanced anesthesia underwent isovolemic hemodilution with hydroxyethyl starch (HAES 6%, 200 000) to a target hb of 7 g dl-1 or 9 g dl-1, respectively. Exchangeable blood volume predicted by use of the different mathematical models was compared with the blood volume actually exchanged to meet the preset target hb.Results: Calculation of EBV by the Bourke and Smith formula (EBVB + S) systematically overestimated the volume actually exchanged (overestimation: dogs 15%, patients 20%), whereas our new iterative model predicted EBV (EBViterative) more reliably (overestimation: dogs 1%, patients 8%). In both cases EBVB + S differed significantly from the EBViterative.Conclusion: Exchangeable blood volume is predicted more accurately by the new iterative model than by the Bourke and Smith formula. The iterative model leads to an improvement in patient safety and provides a physiologically adequate basis for future studies investigating the efficacy of ANH in reducing allogenic blood transfusions. [ABSTRACT FROM AUTHOR]

Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fluorescent microspheres (FM) have become an attractive alternative to radioactive microspheres (RM) for the measurement of regional blood flow (RBF). The aim of the present study was to investigate the comparability of both methods by measuring RBF with FM and RM. Eight anaesthetised pigs received simultaneous, left atrial injections of FM and RM with a diameter of 15 μm at six different time points. Blood reference samples were collected from the descending aorta. RBF was determined in tissue samples of the myocardium, spleen and kidneys of all 8 animals. After radioactivity of the tissue samples was determined, the samples were processed automatically for measuring fluorescence using a recently developed filter device (SPU). RBF was calculated with both the isotope and spectrometric data of both methods for each sample resulting in a total of 10,512 blood flow values. The comparison of the RBF values yielded high linear correlation (mean r[sup 2] = 0.95 ± 0.03 to 0.97 ± 0.02) and excellent agreement (bias 5.4–6.7%, precision 9.9– 16.5%) of both methods. Our results indicate the validity of MS and of the automated tissue processing technique by means of the SPU.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Intraoperative surgical blood loss is initially replaced by infusion of red cell-free, cristalloidal or colloidal solutions. When normovolemia is maintained the ensuing dilutional anemia is compensated by an increase of cardiac output and of arterial oxygen extraction. In the ideal case, a surgical blood loss can entirely be ‘bridged’ without transfusion by intraoperative normovolemic hemodilution. However major blood loss results in extreme hemodilution and the transfusion of red blood cells may finally become necessary to increase arterial oxygen content and to preserve tissue oxygenation. When transfusion has to be started before surgical control of bleeding has been achieved, parts of the red blood cells transfused will get lost, thereby increasing intraoperative transfusion needs. Beside red blood cell transfusion, arterial oxygen content can be rapidly increased by ventilating the patient with 100% oxygen (hyperoxic ventilation), thus enhancing the amount of physically dissolved oxygen in plasma (hyperoxia). In experimental and clinical studies hyperoxic ventilation has emerged as a simple, safe and effective intervention to enlarge the margin of safety for hemodynamic compensation and tissue oxygenation in hemodiluted subjects experiencing major bleeding. The hyperoxia-associated microcirculatory dysregulation and impaired tissue oxygenation known to take place in the presence of a physiologic hemoglobin concentration are not encountered in hemodiluted subjects. Hyperoxic hemodilution i.e. the combination of intraoperative extreme hemodilution and hyperoxic ventilation may therefore be considered a cost-effective, safe and efficient supplement to reduce allogeneic transfusion during surgical interventions associated with high blood losses. The vast majority of the experimental and clinical investigations this new concept is based on was initiated and performed under the guidance of Prof. Konrad Messmer.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Today, the technique to directly administer vasodilators via the airway to treat pulmonary hypertension and to improve pulmonary gas exchange is widely accepted among clinicians. The flood of scientific work focussing on this new therapeutic concept had been initiated by a fundamental new observation by Pepke-Zaba [1]and Frostell in 1991 [2]: Both scientists reported, that inhalation of exogenous nitric oxide (NO) gas selectively dilates pulmonary vessels without a concomittant systemic vasodilation. No more than another decade ago NO was identified as an important endogenous vasodilator [3]while having merely been regarded an environmental pollutant before that time. Although inhaled NO proved to be efficacious, alternatives were sought-after due to NO’s potential side-effects. In search for the ideal inhaled vasodilator another group of endogenous mediators – the prostanoids – came into the focus of interest. The evidence for safety and efficacy of inhaled prostanoids is – among a lot of other valuable work – based on a series of experimental and clinical investigations that have been performed or designed at the Institute for Surgical Research under the guidance and mentorship of Prof. Dr. med. Dr. h.c. mult. K. Messmer [4-19]. In the following, the current and newly emerging clinical applications of inhaled prostanoids and the experimental data which they are based on, will be reviewed.Copyright © 2002 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In severe hemorrhagic shock, left ventricular (LV) diastolic dysfunction is an early sign of cardiac failure due to compromised myocardial oxygenation. Immediate fluid replacement or, in particular, administration of a hemoglobin-based oxygen carrier (diaspirin cross-linked hemoglobin; DCLHb) improves myocardial oxygenation; therefore, positive effects on LV diastolic function could be expected. The effects of fluid resuscitation from severe hemorrhagic shock with DCLHb were investigated in 20 anesthetized domestic pigs. After generation of a critical left anterior descending coronary artery stenosis (narrowing of the artery until disappearance of reactive hyperemia after a 10-second complete vessel occlusion), hemorrhagic shock (mean arterial blood pressure 45 mm Hg) was induced within 15 min by controlled blood withdrawal and maintained for 60 min. Fluid resuscitation consisted of replacement of the plasma volume withdrawn during hemorrhage by infusion of either 10% DCLHb (DCLHb group, n = 10) or 8% human serum albumin (HSA) oncotically matched to DCLHb (HSA group, n = 10). After completion of resuscitation, an observation period of 60 min elapsed. Measurements of central hemodynamics, myocardial oxygenation, and LV diastolic function were performed at baseline, after induction of critical coronary artery stenosis, after 60 min of hemorrhagic shock, immediately after resuscitation, and 60 min later. While 5 out of 10 animals treated with HSA died within the first 20 min after fluid resuscitation from acute LV pump failure, all DCLHb-treated animals survived until the end of the protocol (p < 0.05). Despite superior myocardial oxygenation due to augmentation of the arterial O[sub 2] content as well as of coronary perfusion pressure, no beneficial effects on LV diastolic function were observed after infusion of DCLHb. Peak velocity of LV pressure decrease (dp/dt[sub min] ) did not reveal significant differences between the two groups. Immediately after completion of fluid resuscitation with DCLHb, the time constant of LV diastolic relaxation (τ) was prolonged when compared with HSA-treated animals (p < 0.05), indicating retardation of early LV diastolic relaxation. Our data suggest that DCLHb fails to improve LV diastolic function after fluid resuscitation from severe hemorrhagic shock. However, positive effects on myocardial perfusion and oxygenation result in a significant reduction of the mortality of severe hemorrhagic shock.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report the case of a 22-year-old woman who underwent two-step scoliosis surgery without allogeneic transfusion, although the intraoperative blood loss (3500 ml) during the first procedure was higher than the calculated blood volume (3250 ml). Preoperatively the patient had donated four units of autologous blood. Intraoperatively blood-saving methods were combined. During the first operation acute normovolemic hemodilution (target hemoglobin 9.0 g/dl) was applied and during the second operation controlled hypotension (systolic blood pressure 80 mmHg). Intraoperative auto-transfusion was used in both procedures. During the first operation severe normovolemic anemia (minimal hemoglobin 3.5 g/dl) was accepted while the patient was ventilated with FiO2 1.0. The hemoglobin concentration was 8.6 g/dl after the first procedure and had increased to 11.6 g/dl 4 weeks after the second procedure. No severe complications occurred during the postoperative phase. This case report shows that also in surgical procedures with extreme blood loss any allogenic transfusion can be avoided by the combination of blood-saving methods, acceptance of low intraoperative transfusion trigger and ventilation with 100% oxygen. [ABSTRACT FROM AUTHOR]

For ethical and socio-economical reasons (cost-explosion in transfusion-medicine, patient's individual destiny), development and consistent application of allogeneic transfusion sparing techniques in surgery is a challenge to anesthesiologists, surgeons and blood-bankers. The combination of different techniques, i.e. autologous predonation, hemodilution, choice of anesthetic regimen, deliberate hypotension, application of antifibrinolytic agents and autotransfusion of intraoperatively saved blood allow for avoidance of allogeneic blood transfusion even in patients presenting important intraoperative hemorrhage. The present article summarizes (1) risks associated with transfusion of allogeneic blood, (2) actually applied pre- and intraoperative techniques to reduce transfusion of allogeneic blood and (3) new concepts (administration of erythropoietin, hyperoxic ventilation and administration of artificial oxygen carries) to further increase the efficacy of autologous predonation and preoperative normovolemic hemodilution. [ABSTRACT FROM AUTHOR]

Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concept of small-volume resuscitation, the rapid infusion of a small volume (4 ml/kg BW) of hyperosmolar 7.2-7.5% saline solution for the initial therapy of severe hypovolemia and shock was advocated more than a decade ago. Numerous publications have established that hyperosmolar saline solution can restore arterial blood pressure, cardiac index and oxygen delivery as well as organ perfusion to pre-shock values. Most prehospital studies failed to yield conclusive results with respect to a reduction in overall mortality. A meta-analysis of preclinical studies from North and South America, however, has indicated an increase in survival rate by 5.1% following small-volume resuscitation when compared to standard of care. Moreover, small-volume resuscitation appears to be of specific impact in patients suffering from head injuries with increased ICP and in severest trauma requiring immediate surgical intervention. Results from clinical trials in Austria, Germany and France have demonstrated positive effects of hyperosmolar saline solutions when used for fluid loading or fluid substitution in cardiac bypass and in aortic aneurysm surgery, respectively. A less positive perioperative fluid balance, a better hemodynamic stability and improved pulmonary function were reported. In septic patients oxygen consumption could significantly be augmented. The most important mechanism of action of small-volume resuscitation is the mobilisation of endogenous fluid primarily from oedematous endothelial cells, by which the rectification of shock-narrowed capillaries and the restoration of nutritional blood, flow is efficiently promoted. Moreover, after ischemia reperfusion a reduction in sticking and rolling leukocytes have been found following hyperosmolar saline infusion. Both may be of paramount importance in the long-term preservation of organ function following hypovolemic shock. An increased myocardial contractility in addition to the fluid loading effects of hyperosmolar saline solutions has been suggested as a mechanism of action. This, however, could not be confirmed by pre-load independent measures of myocardial contractility. Some concerns have been raised regarding the use of hyperosmolar saline solutions in patients with a reduced cardiac reserve. A slower speed of infusion and adequate monitoring is recommended for high risk patients. Recently, hyperosmolar saline solutions in combination with artificial oxygen carriers have been proposed to increase tissue oxygen delivery through enhanced O2 content. This interesting perspective, however, requires further studies to confirm the potential indications for such solutions. Many hyperosmolar saline colloid solutions have been investigated in the past years, from which 7.2-7.5% sodium chloride in combination with either 6-10% dextran 60/70 or 6-10% hydroxyethyl starch 200,000 appear to yield the best benefit-risk ratio. This has led to the registration of the solutions in South America, Austria, The Czech Republic, and is soon awaited for North America. [ABSTRACT FROM AUTHOR]

Objective: Inhalation of high concentrations of nitric oxide (NO) has been shown to improve gas exchange and to reduce pulmonary vascular resistance in individuals with ischemia-reperfusion injury following orthotopic lung transplantation. We assessed the cardiopulmonary effects of low doses of NO in early allograft dysfunction following lung transplantation.Design: Prospective clinical dose-response study.Setting: Anesthesiological intensive care unit of a university hospital.Patients and Participants: 8 patients following a single or double lung transplantation who had a mean pulmonary arterial pressure (PAP) in excess of 4.7 kPa (35 mmHg) or an arterial oxygen tension/fractional inspired oxygen ratio (PaO2/FIO2) of less than 13.3 kPa (100 mmHg).Interventions: Gaseous NO was inhaled in increasing concentrations (1, 4 and 8 parts per million, each for 15 min) via a Siemens Servo 300 ventilator.Measurements and Results: Cardiorespiratory parameters were assessed at baseline, after each concentration of NO, and 15 min after withdrawal of the agent [statistics: median (25th/75th percentiles: Q1/Q3), rANOVA, Dunnett's test, p < 0.05]. Inhaled NO resulted in a significant, reversible, dose-dependent, selective reduction in PAP from 5.5(5.2/6.0) kPa at control to 5.1(4.7/5.6) kPa at 1 ppm, 4.9(4.3/5.3) kPa at 4 ppm, and to 4.7(4.1/5.1) kPa at 8 ppm. PaO2 increased from 12.7(10.4/17.1) to 19.2(12.4/26.0) kPa at 1 ppm NO, to 23.9(4.67/26.7) kPa at 4 ppm NO and to 24.5(11.9/28.7) kPa at 8 ppm NO. All patients responded to NO inhalation (either with PAP or PaO2), all were subject to long-term inhalation (1-19 days). All were successfully weaned from NO and were discharged from the intensive care unit.Conclusion: The present study demonstrates that low-dose inhaled NO may be an effective drug for symptomatic treatment of hypoxemia and/or pulmonary hypertension due to allograft dysfunction subsequent to lung transplantation. [ABSTRACT FROM AUTHOR]

Objective: To study potential toxic effects of long-term (8 h) inhaled prostacyclin (PGI2) on respiratory tract tissues.Design: In a prospective, randomized order, either PGI2 (n =7) or normal saline (n = 7) was aerosolized during a time period of 8 h in healthy lambs.Setting: Institute for Surgical Research of the Ludwig-Maximilians University of Munich.Animals: 14 health, anesthetized, ventilated lambs.Interventions: All animals were endotracheally intubated followed by tracheotomy. PGI2 solution or normal saline was administered with a jet nebulizer (delivery rate 4-10 ml/h; mass median diameter of aerosol particles 3.1 microns).Measurements and Results: Histomorphological changes after 8-h inhalation of PGI2 solution were compared to those after 8-h inhalation of normal saline. Tracheal and bronchoalveolar tissues were examined by light and electron microscopy in order to assess tissue damage induced by inhaled PGI2. Pathological changes were ranked by a blinded observer following a graduation system ranging from "absence of pathological changes" to "maximal pathological changes". Abnormalities were restricted to the trachea (focal flattening of the epithelium, loss of cilia, slight inflammatory cell infiltration) and alveolar tissue (focal alveolar septal thickening with slight inflammatory cell infiltration), but no statistically significant differences between the PGI2 and control groups were encountered.Conclusion: Our findings indicate the absence of PGI2 aerosol-related respiratory tissue damage after 8-h inhalation of PGI2. [ABSTRACT FROM AUTHOR]

Objective: To study the potential side effects and toxicity of inhaling prostacyclin (PGI2) aerosol for 8 h.Design: In a prospective, randomized study 14 healthy lambs received either PGI2 (n = 7) or 0.9% NaCl (n = 7) as an aerosol for 8 h.Setting: Institute for Surgical Research of the Ludwig-Maximilians-University of Munich.Interventions: All animals were studied under general anesthesia in a prone position. They were first intubated endotracheally and later tracheotomized. PGI2 solution (median dose 28 ng/kg per min) or 0.9% NaCl was administered with a jet nebulizer (delivery rate 4-10 ml/h; mass median diameter of aerosol particles 3.1 microns). Bronchoalveolar lavage was performed before and after the inhalation period to collect epithelial lining fluid of alveoli.Measurements and Results: Hemodynamic and respiratory parameters, systemic resorption (plasma levels of 6-keto-prostaglandin-F 1 alpha), in vitro bleeding time, collagen-induced platelet aggregation and global biochemical and cellular composition of the epithelial lining fluid were examined in order to assess the side effects and signs of acute pulmonary toxicity induced by inhaled PGI2. No statistically significant differences were found between the PGI2 and the control groups for any of the parameters examined.Conclusion: Inhalation of PGI2 (28 ng/kg per min) over a period of 8 h in healthy lambs does not produce major side effects or acute pulmonary toxicity. [ABSTRACT FROM AUTHOR]

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Presents a letter to the editor about a clinical case of a patient who survived from continous tumor bleeding and dilutional anemia due to aortic valve stenosis.