Management of severe peri-operative bleeding: Guidelines from the European Society of Anaesthesiology and Intensive Care: Second update 2022.

BACKGROUND: Management of peri-operative bleeding is complex and involves multiple assessment tools and strategies to ensure optimal patient care with the goal of reducing morbidity and mortality. These updated guidelines from the European Society of Anaesthesiology and Intensive Care (ESAIC) aim to provide an evidence-based set of recommendations for healthcare professionals to help ensure improved clinical management. DESIGN: A systematic literature search from 2015 to 2021 of several electronic databases was performed without language restrictions. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) was used to assess the methodological quality of the included studies and to formulate recommendations. A Delphi methodology was used to prepare a clinical practice guideline. RESULTS: These searches identified 137 999 articles. All articles were assessed, and the existing 2017 guidelines were revised to incorporate new evidence. Sixteen recommendations derived from the systematic literature search, and four clinical guidances retained from previous ESAIC guidelines were formulated. Using the Delphi process on 253 sentences of guidance, strong consensus (>90% agreement) was achieved in 97% and consensus (75 to 90% agreement) in 3%. DISCUSSION: Peri-operative bleeding management encompasses the patient's journey from the pre-operative state through the postoperative period. Along this journey, many features of the patient's pre-operative coagulation status, underlying comorbidities, general health and the procedures that they are undergoing need to be taken into account. Due to the many important aspects in peri-operative nontrauma bleeding management, guidance as to how best approach and treat each individual patient are key. Understanding which therapeutic approaches are most valuable at each timepoint can only enhance patient care, ensuring the best outcomes by reducing blood loss and, therefore, overall morbidity and mortality. CONCLUSION: All healthcare professionals involved in the management of patients at risk for surgical bleeding should be aware of the current therapeutic options and approaches that are available to them. These guidelines aim to provide specific guidance for bleeding management in a variety of clinical situations.

[Fluid and Volume Therapy with Crystalloid and Colloidal Infusion Solutions]. / Flüssigkeits- und Volumentherapie mit kristalloiden und kolloidalen Lösungen.

A rational infusion therapy orchestrates fluid- and volume therapy based on the individual indication and situation. The principle of fluid replacement is to substitute ongoing fluid losses such as insensible perspiration and urine output or to treat dehydration with balanced crystalloid solutions. Volume therapy in contrast is the quick restoration of intravascular losses such as an acute blood loss through application of balanced colloids or crystalloids. The goal of volume therapy is to maintain normal cardiac output and oxygen delivery by restoring intravascular normovolemia and cardiac preload. Whether colloid or crystalloid infusions are most suitable for volume therapy remains unclear. Most trials in this field are either underpowered or used colloids in inadequate situations, patients and amounts. Two major trials from the European Society of Anaesthesiology and Intensive Care (ESAIC) are underway that seem promising to provide evidence in this emotional debate.

A Prospective Observational Study of Rational Fluid Therapy in Asian Intensive Care Units: Another Puzzle Piece in Fluid Therapy.

INTRODUCTION: Fluid therapy in critically ill patients, especially timing and fluid choice, is controversial. Previous randomized trials produced conflicting results. This observational study evaluated the effect of colloid use on 90-day mortality and acute kidney injury (RIFLE F) within the Rational Fluid Therapy in Asia (RaFTA) registry in intensive care units. MATERIALS AND METHODS: RaFTA is a prospective, observational study in Asian intensive care unit (ICU) patients focusing on fluid therapy and related outcomes. Logistic regression was performed to identify risk factors for increased 90-day mortality and acute kidney injury (AKI). RESULTS: Twenty-four study centers joined the RaFTA registry and collected 3,187 patient data sets from November 2011 to September 2012. A follow-up was done 90 days after ICU admission. For 90-day mortality, significant risk factors in the overall population were sepsis at admission (OR 2.185 [1.799; 2.654], p < 0.001), cumulative fluid balance (OR 1.032 [1.018; 1.047], p < 0.001), and the use of vasopressors (OR 3.409 [2.694; 4.312], p < 0.001). The use of colloids was associated with a reduced risk of 90-day mortality (OR 0.655 [0.478; 0.900], p = 0.009). The initial colloid dose was not associated with an increased risk for AKI (OR 1.094 [0.754; 1.588], p = 0.635). CONCLUSION: RaFTA adds the important finding that colloid use was not associated with increased 90-day mortality or AKI after adjustment for baseline patient condition. CLINICAL SIGNIFICANCE: Early resuscitation with colloids showed potential mortality benefit in the present analysis. Elucidating these findings may be an approach for future research. HOW TO CITE THIS ARTICLE: Jacob M, Sahu S, Singh YP, Mehta Y, Yang K-Y, Kuo S-W, et al. A Prospective Observational Study of Rational Fluid Therapy in Asian Intensive Care Units: Another Puzzle Piece in Fluid Therapy. Indian J Crit Care Med 2020;24(11):1028-1036.

Rational application of antibiotics-The influence of anaesthetists' gender on self-confidence and knowledge.

BACKGROUND: High rates of multiresistant pathogens require detailed knowledge about rational utilization of antibiotics. Many physicians consider themselves uncertain about the interpretation of microbiological diagnostics. We examined whether self-confidence, self-rated knowledge, and objective knowledge regarding the use of antibiotics are associated with gender. METHODS: For this survey study, in 2017, anaesthesiologists and residents of 16 anaesthetic departments in Germany were asked to complete the Multiinstitutional Reconnaissance of practice with Multiresistant bacteria (MR2) survey. It consists of 55 items evaluating self-confidence regarding the practical use of antibiotics (n = 6), self-rated theoretical knowledge (n = 16), and objective knowledge (n = 5). Their answers to these items in relation to their gender were analysed using Chi-square, Kruskal-Wallis-H-Tests, and unadjusted as well as adjusted logistic regression models. RESULTS: Six hundred eighty-four (response rate: 53.9 %) questionnaires were returned and were available for analysis. Female doctors (35.5 %) felt less self-confident (P < 0.001). Self-rated knowledge differed in overall mean (P = 0.014) and the unadjusted (odds ratio [OR]: 0.55; P = 0.013) but not in the adjusted logistic regression (OR: 0.84; P = 0.525). Objective knowledge differed after pooling questions (61.2% correct answers vs 65.4%, P = 0.01) but not with respect to single items and the adjusted logistic regression (OR: 0.83, P = 0.356). CONCLUSION: Less self-confidence and a lower self-rated knowledge were found in female anaesthetists; this is consistent to the gender phenomena observed by other researchers. Nevertheless, between the 2 groups objective knowledge did not differ significantly in any item.

Management of severe perioperative bleeding: guidelines from the European Society of Anaesthesiology: First update 2016.

: The management of perioperative bleeding involves multiple assessments and strategies to ensure appropriate patient care. Initially, it is important to identify those patients with an increased risk of perioperative bleeding. Next, strategies should be employed to correct preoperative anaemia and to stabilise macrocirculation and microcirculation to optimise the patient's tolerance to bleeding. Finally, targeted interventions should be used to reduce intraoperative and postoperative bleeding, and so prevent subsequent morbidity and mortality. The objective of these updated guidelines is to provide healthcare professionals with an overview of the most recent evidence to help ensure improved clinical management of patients. For this update, electronic databases were searched without language restrictions from 2011 or 2012 (depending on the search) until 2015. These searches produced 18 334 articles. All articles were assessed and the existing 2013 guidelines were revised to take account of new evidence. This update includes revisions to existing recommendations with respect to the wording, or changes in the grade of recommendation, and also the addition of new recommendations. The final draft guideline was posted on the European Society of Anaesthesiology website for four weeks for review. All comments were collated and the guidelines were amended as appropriate. This publication reflects the output of this work.

Regulation of blood flow and volume exchange across the microcirculation.

Oxygen delivery to cells is the basic prerequisite of life. Within the human body, an ingenious oxygen delivery system, comprising steps of convection and diffusion from the upper airways via the lungs and the cardiovascular system to the microvascular area, bridges the gap between oxygen in the outside airspace and the interstitial space around the cells. However, the complexity of this evolutionary development makes us prone to pathophysiological problems. While those problems related to respiration and macrohemodynamics have already been successfully addressed by modern medicine, the pathophysiology of the microcirculation is still often a closed book in daily practice. Nevertheless, here as well, profound physiological understanding is the only key to rational therapeutic decisions. The prime guarantor of tissue oxygenation is tissue blood flow. Therefore, on the premise of intact macrohemodynamics, the microcirculation has three major responsibilities: 1) providing access for oxygenated blood to the tissues and appropriate return of volume; 2) maintaining global tissue flood flow, even in the face of changes in central blood pressure; and 3) linking local blood flow to local metabolic needs. It is an intriguing concept of nature to do this mainly by local regulatory mechanisms, impacting primarily on flow resistance, be this via endothelial or direct smooth muscle actions. The final goal of microvascular blood flow per unit of time is to ensure the needed exchange of substances between tissue and blood compartments. The two principle means of accomplishing this are diffusion and filtration. While simple diffusion is the quantitatively most important form of capillary exchange activity for the respiratory gases, water flux across the blood-brain barrier is facilitated via preformed specialized channels, the aquaporines. Beyond that, the vascular barrier is practically nowhere completely tight for water, with paracellular filtration giving rise to generally low but permanent fluid flux outwards into the interstitial space at the microvascular high pressure segment. At the more leaky venular aspect, both filtration and diffusion allow for bidirectional passage of water, nutrients, and waste products. We are just beginning to appreciate that a major factor for maintaining tissue fluid homeostasis appears to be the integrity of the endothelial glycocalyx.

RhEPO improves time to exhaustion by non-hematopoietic factors in humans.

PURPOSE: Erythropoietin (EPO) controls red cell volume (RCV) and plasma volume (PV). Therefore, injecting recombinant human EPO (rhEPO) increases RCV and most likely reduces PV. RhEPO-induced endurance improvements are explained by an increase in blood oxygen (O2) transport capacity, which increases maximum O2 uptake ([Formula: see text]O2max). However, it is debatable whether increased RCV or [Formula: see text]O2max are the main reasons for the prolongation of the time to exhaustion (t lim) at submaximal intensity. We hypothesized that high rhEPO doses in particular contracts PV such that the improvement in t lim is not as strong as at lower doses while [Formula: see text]O2max increases in a dose-dependent manner. METHODS: We investigated the effects of different doses of rhEPO given during 4 weeks [placebo (P), low (L), medium (M), and high (H) dosage] on RCV, PV, [Formula: see text]O2max and t lim in 40 subjects. RESULTS: While RCV increased in a dose-dependent manner, PV decreased independent of the rhEPO dose. The improvements in t lim (P +21.4 ± 23.8%; L +16.7 ± 29.8%; M +44.8 ± 62.7%; H +69.7 ± 73.4%) depended on the applied doses (R (2) = 0.89) and clearly exceeded the dose-independent [Formula: see text]O2max increases (P -1.7 ± 3.2%; L +2.6 ± 6.8%; M +5.7 ± 5.1 %; H +5.6 ± 4.3 %) after 4 weeks of rhEPO administration. Furthermore, the absolute t lim was not related (R (2) ≈ 0) to RCV or to [Formula: see text]O2max. CONCLUSIONS: We conclude that a contraction in PV does not negatively affect t lim and that rhEPO improves t lim by additional, non-hematopoietic factors.

Degradation of the endothelial glycocalyx in clinical settings: searching for the sheddases.

The endothelial glycocalyx has a profound influence at the vascular wall on the transmission of shear stress, on the maintenance of a selective permeability barrier and a low hydraulic conductivity, and on attenuating firm adhesion of blood leukocytes and platelets. Major constituents of the glycocalyx, including syndecans, heparan sulphates and hyaluronan, are shed from the endothelial surface under various acute and chronic clinical conditions, the best characterized being ischaemia and hypoxia, sepsis and inflammation, atherosclerosis, diabetes, renal disease and haemorrhagic viral infections. Damage has also been detected by in vivo microscopic techniques. Matrix metalloproteases may shed syndecans and heparanase, released from activated mast cells, cleaves heparan sulphates from core proteins. According to new data, not only hyaluronidase but also the serine proteases thrombin, elastase, proteinase 3 and plasminogen, as well as cathepsin B lead to loss of hyaluronan from the endothelial surface layer, suggesting a wide array of potentially destructive conditions. Appropriately, pharmacological agents such as inhibitors of inflammation, antithrombin and inhibitors of metalloproteases display potential to attenuate shedding of the glycocalyx in various experimental models. Also, plasma components, especially albumin, stabilize the glycocalyx and contribute to the endothelial surface layer. Though symptoms of the above listed diseases and conditions correlate with sequelae expected from disturbance of the endothelial glycocalyx (oedema, inflammation, leukocyte and platelet adhesion, low reflow), therapeutic studies to prove a causal connection have yet to be designed. With respect to studies on humans, some clinical evidence exists for benefits from application of sulodexide, a preparation delivering precursors of the glycocalyx constituent heparan sulphate. At present, the simplest option for protecting the glycocalyx seems to be to ensure an adequate level of albumin. However, also in this case, definite proof of causality needs to be delivered.

The impact of hydroxyethyl starches in cardiac surgery: a meta-analysis.

INTRODUCTION: Recent studies in septic patients showed that adverse effects of hydroxyethyl starches (HESs) possibly outweigh their benefits in severely impaired physiological haemostasis. It remains unclear whether this also applies to patient populations that are less vulnerable. In this meta-analysis, we evaluated the impact of various HES generations on safety and efficacy endpoints in patients undergoing cardiac surgery. METHODS: We searched the PubMed, Embase and Cochrane Central Register of Controlled Trials databases for randomised controlled trials (RCTs) in the English or German language comparing the use of HES to any other colloid or crystalloid during open heart surgery. RESULTS: Blood loss and transfusion requirements were higher for older starches with mean molecular weights more than 200 kDa compared to other volume substitutes. In contrast, this effect was not observed with latest-generation tetrastarches (130/0.4), which performed even better when compared to albumin (blood loss of tetrastarch versus albumin: standardised mean difference (SMD), -0.34; 95% CI, -0.63, -0.05; P = 0.02; versus gelatin: SMD, -0.06; 95% CI, -0.20, 0.08; P = 0.39; versus crystalloids: SMD, -0.05; 95% CI, -0.20, 0.10; P = 0.54). Similar results were found for transfusion needs. Lengths of stay in the intensive care unit or hospital were significantly shorter with tetrastarches compared to gelatin (intensive care unit: SMD, -0.10; 95% CI, -0.15, -0.05; P = 0.0002) and crystalloids (hospital: SMD, -0.52; 95% CI, -0.90, -0.14; P = 0.007). CONCLUSIONS: In this meta-analysis of RCTs, we could not identify safety issues with tetrastarches compared with other colloid or crystalloid solutions in terms of blood loss, transfusion requirements or hospital length of stay in patients undergoing cardiac surgery. The safety data on coagulation with older starches raise some issues that need to be addressed in future trials.

Albumin administration in the acutely ill: what is new and where next?

Albumin solutions have been used worldwide for the treatment of critically ill patients since they became commercially available in the 1940s. However, their use has become the subject of criticism and debate in more recent years. Importantly, all fluid solutions have potential benefits and drawbacks. Large multicenter randomized studies have provided valuable data regarding the safety of albumin solutions, and have begun to clarify which groups of patients are most likely to benefit from their use. However, many questions remain related to where exactly albumin fits within our fluid choices. Here, we briefly summarize some of the physiology and history of albumin use in intensive care before offering some evidence-based guidance for albumin use in critically ill patients.

Hypervolemia increases release of atrial natriuretic peptide and shedding of the endothelial glycocalyx.

INTRODUCTION: Acute normovolemic hemodilution (ANH) and volume loading (VL) are standard blood-sparing procedures. However, VL is associated with hypervolemia, which may cause tissue edema, cardiopulmonary complications and a prolonged hospital stay. The body reacts to hypervolemia with release of atrial natriuretic peptide (ANP) from the heart. ANP has been shown to deteriorate the endothelial glycocalyx, a vital part of the vascular permeability barrier. The aim of the present study was to evaluate and compare ANP release and damage to the glycocalyx during ANH and VL. METHODS: ANH or VL with 6% hydroxyethyl starch 130/0.4 was administered prior to elective surgery in patients of good cardiopulmonary health (n =9 in each group). We measured concentrations of ANP in plasma and of three main constituent parts of the glycocalyx (hyaluronan, heparan sulfate and syndecan 1) in serum before and after ANH or VL. Heparan sulfate and syndecan 1 levels in urine were also determined. RESULTS: In contrast to ANH, VL (20 ml/kg) induced a significant release of ANP (approximately +100%, P <0.05) and increased the serum concentration of two glycocalyx constituents, hyaluronan and syndecan 1 (both by about 80%, P <0.05). Elevation of syndecan 1 was also detected in the urine of patients undergoing VL, but no increase was found in patients undergoing ANH. Heparan sulfate levels were not influenced by either procedure. CONCLUSION: These data suggest that hypervolemia increases the release of ANP and causes enhanced shedding of the endothelial glycocalyx. This perturbation must be expected to impair the vascular barrier, implying that VL may not be as safe as generally assumed and that it should be critically evaluated.

Protection of glycocalyx decreases platelet adhesion after ischaemia/reperfusion: an animal study.

BACKGROUND: Strategies targeting the protection of the vascular barrier, in particular the endothelial glycocalyx, are subjects of current research. Antithrombin III and hydrocortisone have been shown to reduce shedding of the glycocalyx following ischaemia/reperfusion. Platelet adhesion to endothelial cells is one consequence of ischaemia/reperfusion. OBJECTIVE: Our goal was to evaluate the effect of pharmacological protection of the glycocalyx on platelet adhesion. DESIGN: An experimental interventional animal study. SETTING: The study was carried out in a basic science laboratory at the University of Munich. ANIMALS: Eighty male guinea pigs (250 to 300 g) were used for the experiment. MAIN OUTCOME MEASURES: The effect of preischaemic treatment with hydrocortisone 10 µg ml(-1) or antithrombin 1 IU ml on adherence of platelets was evaluated in isolated, beating guinea pig hearts (Langendorff model). Hearts were subjected to warm ischaemia (20 min at 37 °C) and consecutive reperfusion. Platelets were injected at the beginning of reperfusion via the aortic cannula and platelet concentration was measured in the effluent (after passing through the coronary vascular system). RESULTS: Ischaemia and reperfusion led to significant shedding of the endothelial glycocalyx. Coronary venous release of syndecan-1 increased nine-fold, and heparan sulphate showed a 20.3-fold increase after ischaemia/reperfusion (both P < 0.01). Pretreatment with hydrocortisone or antithrombin III reduced endothelial glycocalyx shedding significantly (P < 0.05). Adherence of platelets to the coronary vascular bed increased more than 2.5-fold when they were injected during reperfusion. About 40% of this increase was blocked by pretreatment of hearts with hydrocortisone or antithrombin. CONCLUSION: Pretreatment with hydrocortisone or antithrombin III can reduce platelet adhesion during reperfusion after warm ischaemia by protection of the endothelial glycocalyx.

Physiological levels of A-, B- and C-type natriuretic peptide shed the endothelial glycocalyx and enhance vascular permeability.

Atrial natriuretic peptide (ANP) is a peptide hormone released from the cardiac atria during hypervolemia. Though named for its well-known renal effect, ANP has been demonstrated to acutely increase vascular permeability in vivo. Experimentally, this phenomenon was associated with a marked shedding of the endothelial glycocalyx, at least for supraphysiological intravascular concentrations. This study investigates the impact and mechanism of action of physiological doses of ANP and related peptides on the vascular barrier. In isolated guinea pig hearts, prepared and perfused in a modified Langendorff mode with and without the intravascular presence of the colloid hydroxyethyl starch (HES), we measured functional changes in vascular permeability and glycocalyx shedding related to intracoronary infusion of physiological concentrations of A-, B- and C-type natriuretic peptide (ANP, BNP and CNP). Significant coronary venous washout of glycocalyx constituents (syndecan-1 and heparan sulfate) was observed. As tested for ANP, this effect was positively related to the intracoronary concentration. Intravascular shedding of the glycocalyx was morphologically confirmed by electron microscopy. Also, functional vascular barrier competence decreased, as indicated by significant increases in transudate formation and HES extravasation. Ortho-phenanthroline, a non-specific inhibitor of matrix metalloproteases, was able to reduce ANP-induced glycocalyx shedding. These findings suggest participation of natriuretic peptides in pathophysiological processes like heart failure, inflammation or sepsis. Inhibition of metalloproteases might serve as a basis for future therapeutical options.

Effect of waxy maize-derived hydroxyethyl starch 130/0.4 on renal function in surgical patients.

BACKGROUND: The aim of this meta-analysis was to evaluate renal safety with the active substance of the latest generation of waxy maize-derived hydroxyethyl starch in surgical patients. The authors focused on prospective, randomized, controlled studies that documented clinically relevant variables with regard to renal effects of waxy maize-derived hydroxyethyl starch 130/0.40. MATERIALS AND METHODS: The authors carefully searched for all available prospective, randomized studies and evaluated the greatest delta from baseline values in renal safety variables (serum creatinine values, calculated creatinine clearance, incidence of renal replacement therapy, and acute renal failure). The authors included 17 studies that analyzed patients (n = 1,230) undergoing a variety of surgical procedures. RESULTS: For maximum serum creatinine values, the effect size estimate was 0.068 (95% CI = -0.227 to 0.362), P = 0.65. For calculated creatinine clearance values, pooled risk difference was 0.302 (95% CI = -0.098 to 0.703), P = 0.14. For incidence of acute renal failure, pooled risk difference was 0.0003 (95% CI = -0.018 to 0.019), P = 0.98. For incidence of renal replacement therapy, pooled risk difference was -0.003 (95% CI = -0.028 to 0.022), P = 0.85. CONCLUSIONS: The authors found no evidence for renal dysfunction caused by modern waxy maize-derived hydroxyethyl starch 130/0.40 in surgical patients.

Reappraising Starling: the physiology of the microcirculation.

PURPOSE OF REVIEW: Vascular permeability is traditionally explained by Starling's principle, describing two opposing forces across the endothelial cell line to maintain compartments in balance. Several contradictions to this principle have recently questioned its validity. RECENT FINDINGS: Hydraulic conductivity is kept low by a properly working endothelial surface layer, created by binding and intercalating plasma constituents with the structural elements of an endothelial glycocalyx. Limiting fluid filtration is not closely related to the interstitial protein concentration. Rather, the oncotic pressure difference pertinent to fluid homeostasis is built up between the intravascular space and a small protein-free zone beneath the protein-loaded endothelial glycocalyx. This crucial structure, and therefore the resistance of the barrier against outflow of large molecules, is endangered by ischaemia, inflammation and intravascular hypervolaemia. An intact endothelial surface layer retains iso-oncotic preparations of large molecules infused to compensate for acute bleeding. Crystalloids cannot be held back sufficiently, even if preload is warranted. SUMMARY: Starling's principle requires an adaptation to recognize that there is no inward-directed oncotic pressure gradient across the whole anatomical vessel wall. The carrier of vascular barrier competence is the intact endothelial surface layer which might be protected by avoiding intravascular hypervolaemia and limiting inflammation.

The impact of crystalloidal and colloidal infusion preparations on coronary vascular integrity, interstitial oedema and cardiac performance in isolated hearts.

INTRODUCTION: Recent data suggested an interaction between plasma constituents and the endothelial glycocalyx to be relevant for vascular barrier function. This might be negatively influenced by infusion solutions, depending on ionic composition, pH and binding properties. The present study evaluated such an influence of current artificial preparations. METHODS: Isolated guinea pig hearts were prepared in a modified Langendorff mode and perfused with Krebs-Henseleit buffer augmented with 1g% human albumin. After equilibration the perfusion was switched to replacement of one half buffer by either isotonic saline (NaCl), ringer's acetate (Ri-Ac), 6% and 10% hydroxyethyl starch (6% and 10% HES, resp.), or 4% gelatine (Gel), the artificial colloids having been prepared in balanced solution. We analysed glycocalyx shedding, functional integrity of the vascular barrier and heart performance. RESULTS: While glycocalyx shedding was not observed, diluting albumin concentration towards 0.5g% by artificial solutions was associated with a marked functional breakdown of vascular barrier competence. This effect was biggest with isotonic saline and significantly attenuated with artificial colloids, the difference in the pressure dependent transvascular fluid filtration (basal vs. during infusion in groups NaCl, Ri-Ac, 6% HES, 10% HES and Gel, n = 6 each) being 0.31 ± 0.03 vs. 1.00 ± 0.04; 0.27 ± 0.03 vs. 0.81 ± 0.03; 0.29 ± 0.03 vs. 0.68 ± 0.02; 0.32 ± 0.03 vs. 0.59 ± 0.08 and 0.31 ± 0.04 vs. 0.61 ± 0.03 g/5min, respectively. Heart performance was directly related to pH value (7.38 ± 0.06, 7.33 ± 0.03, 7.14 ± 0.04, 7.08 ± 0.04, 7.25 ± 0.03), the change in the rate pressure product being 21,702 ± 1969 vs. 21,291 ± 2,552; 22,098 ± 2,115 vs. 14,114 ± 3,386; 20,897 ± 2,083 vs. 10,671 ± 1,948; 21,822 ± 2,470 vs. 10,047 ± 2,320 and 20,955 ± 2,296 vs. 15,951 ± 2,755 mmHg × bpm, respectively. CONCLUSIONS: It appears important to maintain the pH value within a physiological range to maintain optimal myocardial contractility. Using colloids prepared in calcium-containing, balanced solutions for volume replacement therapy may attenuate the breakdown of vascular barrier competence in the critically ill.

Re-evaluating currently available data and suggestions for planning randomised controlled studies regarding the use of hydroxyethyl starch in critically ill patients - a multidisciplinary statement.

INTRODUCTION: Hydroxyethyl starch (HES) is a commonly used colloid in critically ill patients. However, its safety has been questioned in recent studies and meta-analyses. METHODS: We re-evaluated prospective randomised controlled trials (RCT) from four meta-analyses published in 2013 that compared the effect of HES with crystalloids in critically ill patients, focusing on the adherence to 'presumably correct indication'. Regarding the definition of 'presumably correct indication', studies were checked for the following six criteria (maximum six points): short time interval from shock to randomisation (<6 h), restricted use for initial volume resuscitation, use of any consistent algorithm for haemodynamic stabilisation, reproducible indicators of hypovolaemia, maximum dose of HES, and exclusion of patients with pre-existing renal failure or renal replacement therapy. RESULTS: Duration of fluid administration ranged from 90 min up to a maximum of 90 days. Four studies considered follow-up until 90-day mortality, three studies 28-/30-day mortality, whereas four studies reported only early mortality. Included studies showed a large heterogeneity of the indication score ranging between 1 and 4 points with a median (25%; 75% quartile) of 4 (2; 4). CONCLUSIONS: The most important question, whether or not HES may be harmful when it is limited to immediate haemodynamic stabilisation, cannot be answered yet in the absence of any study sufficiently addressing this question. In order to overcome the limitations of most of the previous studies, we now suggest an algorithm emphasising the strict indication of HES. Additionally, we give a list of suggestions that should be adequately considered in any prospective RCT in the field of acute volume resuscitation in critically ill patients.

Management of severe perioperative bleeding: guidelines from the European Society of Anaesthesiology.

The aims of severe perioperative bleeding management are three-fold. First, preoperative identification by anamesis and laboratory testing of those patients for whom the perioperative bleeding risk may be increased. Second, implementation of strategies for correcting preoperative anaemia and stabilisation of the macro- and microcirculations in order to optimise the patient's tolerance to bleeding. Third, targeted procoagulant interventions to reduce the amount of bleeding, morbidity, mortality and costs. The purpose of these guidelines is to provide an overview of current knowledge on the subject with an assessment of the quality of the evidence in order to allow anaesthetists throughout Europe to integrate this knowledge into daily patient care wherever possible. The Guidelines Committee of the European Society of Anaesthesiology (ESA) formed a task force with members of scientific subcommittees and individual expert members of the ESA. Electronic databases were searched without language restrictions from the year 2000 until 2012. These searches produced 20 664 abstracts. Relevant systematic reviews with meta-analyses, randomised controlled trials, cohort studies, case-control studies and cross-sectional surveys were selected. At the suggestion of the ESA Guideline Committee, the Scottish Intercollegiate Guidelines Network (SIGN) grading system was initially used to assess the level of evidence and to grade recommendations. During the process of guideline development, the official position of the ESA changed to favour the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. This report includes general recommendations as well as specific recommendations in various fields of surgical interventions. The final draft guideline was posted on the ESA website for four weeks and the link was sent to all ESA members. Comments were collated and the guidelines amended as appropriate. When the final draft was complete, the Guidelines Committee and ESA Board ratified the guidelines.