C. von Heymann

Torsemide Versus Furosemide After Continuous Renal Replacement Therapy Due to Acute Renal Failure in Cardiac Surgery Patients

Diuretic therapy in ARF (acute renal failure) is mainly done with loop diuretics, first of all furosemide. Torsemide has a longer duration of action and does not accumulate in renal failure. In chronic and acute renal failure, both diuretics have been effectively applied, with a more pronounced diuretic effect for torsemide. In this study, the effects of torsemide versus furosemide on renal function in cardiac surgery patients recovering from ARF after continuous renal replacement therapy (CRRT) were studied. Twenty-nine critically ill patients admitted to an intensive care unit at a university teaching hospital after cardiac surgery recovering from ARF after CRRT were included in this prospective, controlled, single-center, open-labeled, randomized clinical trial. Inclusion criteria were urine output > 0.5 mL/kg/h over 6 h under CRRT. Torsemide and furosemide dosages were adjusted with the target urine output being 0.8–1.5 mL/kg/h. Hemodynamic data, urine output, volume balance, serum creatinine clearance, electrolytes, blood urea nitrogen, serum creatinine, renin, and aldosterone concentrations were measured. Fourteen patients were included in the furosemide group and 15 patients in the torsemide group. Dosages of 29 (0–160) mg torsemide and a dosage of 60 (0–240) mg furosemide were given every 6 h in each group, respectively. The dosage given at the end of the study decreased significantly in furosemide and torsemide treated patients. Urine output, 24 h balance, and serum creatinine clearance did not differ significantly between groups. Urine output decreased in both groups, mostly dose-dependent in the torsemide group. The intragroup comparison of the first time-interval after inclusion with the last time-interval showed a significant increase in serum creatinine and blood urea nitrogen in the furosemide group. Renin and aldosterone concentrations did not show significant differences. In conclusion, torsemide and furosemide were effective in increasing urine output. Torsemide might show a better dose-dependent diuretic effect in ARF patients after CRRT treatment. Serum creatinine and blood urea nitrogen elimination were less pronounced in the furosemide group.

Cardiac Output Measurement by Arterial Waveform Analysis in Cardiac Surgery – a Comparison of Measurements Derived from Waveforms of the Radial Artery versus the Ascending Aorta

In cardiac surgery, perioperative haemodynamic management is often guided by cardiac output (CO) measurements. The Vigileo™ monitor offers uncalibrated CO measurement by arterial waveform analysis (COwave). This validation study compared CO measurements derived from radial artery waveform analysis with those derived from the ascending aorta. CO measurements from the radial artery versus the ascending aorta showed a significant correlation before and after cardiopulmonary bypass (CPB). However, Bland–Altman analysis showed a mean bias of 0.1 l/min and 0.1 l/min, and limits of agreement (LOA) of +2.2 l/min and −1.9 l/min prior to CPB, and +2.5 l/min and −2.7 l/min after weaning from CPB. A comparison of these CO measurements showed a low mean bias, but wide LOA before and after CPB. Therefore measurements using uncalibrated COwave have to be interpreted with caution in a clinical situation.

Clinical relevance of measuring colonic permeability

Background  Gastroduodenal and small intestinal permeability are increased in patients with Crohns disease (CD) and intensive care patients. The relevance of colonic permeability has not yet been adequately investigated. The aim of this study was to investigate the clinical value of sucralose excretion as indicator for colonic permeability in these patient groups.

Profound haemodilution during normothermic cardiopulmonary bypass influences neither gastrointestinal permeability nor cytokine release in coronary artery bypass graft surgery

BACKGROUND Cardiopulmonary bypass (CPB) impairs intestinal barrier function and induces systemic inflammation after cardiac surgery. The objective of this study was to evaluate the effect of profound haemodilution (haematocrit 19-21%) during normothermic CPB on gastrointestinal permeability and cytokine release in comparison with a standard haemodilution (haematocrit 24-26%). METHODS This was a prospective, controlled, randomized pilot trial of 60 patients without gastrointestinal disease undergoing normothermic CPB (35.5-36 degrees C) for coronary artery bypass graft surgery. Gastrointestinal permeability was measured by the triple-sugar technique (sucrose, lactulose, and mannitol excretion in urine) before and after CPB. Interleukin (IL)-6, IL-10, and tumour necrosis factor alpha (TNFalpha) were quantified using enzyme-linked immunosorbent assays. RESULTS Data from 59 patients (19-21% haematocrit, n=28; 24-26% haematocrit, n=31) were analysed. Data on gastrointestinal permeability were available for 47 patients (19-21% haematocrit, n=23; 24-26% haematocrit, n=24), blood samples for cytokine analysis from 59 patients. Mannitol excretion was normal before and after surgery without significant differences between the groups (after operation: 5.4% vs 2.9%, P=0.193). Lactulose and sucrose excretion was within a normal range before surgery and increased afterwards without differences between the groups. IL-6, IL-10, and TNFalpha were elevated after surgery, but there was no difference between the groups [IL-6 (P=0.78), IL-10 (P=0.74), and TNFalpha (P=0.67)]. CONCLUSIONS Profound haemodilution during normothermic CPB brought about significant changes neither in intestinal permeability nor in cytokine release. It may be concluded that a haematocrit of 19-21% during normothermic CPB does not impair intestinal barrier function and cytokine response in patients without gastrointestinal comorbidity.

Perioperatives anästhesiologisches Management bei ausgedehnten Leberteilresektionen

ZusammenfassungDie Bedeutung der Leberteilresektion als potenziell kurative Therapie bei Tumoren der Leber hat in den letzten Jahrzehnten zugenommen. Verantwortlich hierfür sind einerseits eine gesunkene perioperative Letalität und Morbidität durch Fortschritte im chirurgischen und anästhesiologischen Management sowie andererseits die gestiegene Inzidenz von hepatozellulären Karzinomen. Heute wird die Leberteilresektion in Zentren regelhaft und sicher durchgeführt. Dieser Beitrag beschreibt zunächst die pathophysiologischen Veränderungen, die bei einer Leberinsuffizienz und nach ausgedehnten Leberteilresektionen auftreten können, und gibt Empfehlungen zur präoperativen Abklärung der Patienten. Im zweiten Teil wird das perioperative anästhesiologische Management dargestellt, unter Berücksichtigung von Besonderheiten der Narkoseführung, des Volumenmanagements, der Techniken zur Verringerung des Blutverlusts, der perioperativen Analgesie und der postoperativen Intensivtherapie.AbstractThe importance of partial liver resection as a therapeutic option to cure hepatic tumors has increased over the last decades. This has been influenced on the one hand by advances in surgical and anesthetic management resulting in a reduced mortality after surgery and on the other hand by an increased incidence of hepatocellular carcinoma. Nowadays, partial resection of the liver is performed safely and as a routine operation in specialized centers. This article describes the pathophysiological changes secondary to liver failure and assesses the perioperative management of patients undergoing partial or extended liver resection. It looks in detail at the preoperative assessment, the intraoperative anesthetic management including fluid management and techniques to reduce blood loss as well as postoperative analgesia and intensive care therapy.The importance of partial liver resection as a therapeutic option to cure hepatic tumors has increased over the last decades. This has been influenced on the one hand by advances in surgical and anesthetic management resulting in a reduced mortality after surgery and on the other hand by an increased incidence of hepatocellular carcinoma. Nowadays, partial resection of the liver is performed safely and as a routine operation in specialized centers. This article describes the pathophysiological changes secondary to liver failure and assesses the perioperative management of patients undergoing partial or extended liver resection. It looks in detail at the preoperative assessment, the intraoperative anesthetic management including fluid management and techniques to reduce blood loss as well as postoperative analgesia and intensive care therapy.

Hämodynamisches Monitoring in der perioperativen Phase

ZusammenfassungEin regulärer Hydratationsstatus und Normovolämie sind Ziele der intra-/perioperativen Flüssigkeits- sowie Volumentherapie und gleichzeitig Voraussetzungen für eine adäquate Hämodynamik zur Sicherstellung einer ausreichenden Gewebeoxygenierung. Die physiologischen und pathophysiologischen Effekte der Flüssigkeits- und Volumentherapie beruhen auf den pharmakologischen Eigenschaften der verwendeten Infusionslösung, dem applizierten Volumen und – nach neueren Erkenntnissen – auch auf dem Zeitpunkt der Flüssigkeitsgabe. In der perioperativen Phase unterliegt der Organismus den hormonellen Bedingungen der metabolischen Stressantwort, die neben den perioperativen Änderungen der Gefäßpermeabilität zu berücksichtigen sind. Das Ziel des hämodynamischen Monitorings im OP ist es, Informationen über die Hämodynamik und das globale Sauerstoffangebot zu gewinnen, die eine Abschätzung des intravasalen Volumenstatus des Patienten erlauben. Dies kann die Volumen- und Flüssigkeitstherapie im Sinne einer Konstanthaltung des Herzzeitvolumens verbessern, das vor allen Dingen für Risikopatienten relevant ist. Eine verbesserte und hypovoläme Zustände vermeidende Volumentherapie kann das postoperative Outcome der Patienten positiv beeinflussen. Ziel dieser Arbeit ist es, dem Leser einen Überblick über die aktuell im klinischen Alltag zur Verfügung stehenden Monitoringverfahren zur Einschätzung des perioperativen Volumenstatus zu geben; hierzu werden jeweils das Messprinzip, die Messparameter sowie die Vor- und Nachteile des jeweiligen Verfahrens dargestellt. Weiter wird diskutiert, welche Monitoringverfahren in klinischen Studien schon zur zielgerichteten perioperativen Flüssigkeits- und Volumentherapie („goal-directed therapy“) untersucht wurden.AbstractA regular hydration status and compensated vascular filling are targets of perioperative fluid and volume management and, in parallel, represent precautions for sufficient stroke volume and cardiac output to maintain tissue oxygenation. The physiological and pathophysiological effects of fluid and volume replacement mainly depend on the pharmacological properties of the solutions used, the magnitude of the applied volume as well as the timing of volume replacement during surgery. In the perioperative setting surgical stress induces physiological and hormonal adaptations of the body, which in conjunction with an increased permeability of the vascular endothelial layer influence fluid and volume management. The target of haemodynamic monitoring in the operation room is to collect data on haemodynamics and global oxygen transport, which enable the anaesthetist to estimate the volume status of the vascular system. Particularly in high risk patients this may improve fluid and volume therapy with respect to maintaining cardiac output. A goal-directed volume management aiming at preventing hypovolaemia may improve the outcome after surgery. The objective of this article is to review the monitoring devices that are currently used to assess haemodynamics and filling status in the perioperative setting. Methods and principles for measuring haemodynamic variables, the measured and calculated parameters as well as clinical benefits and shortcomings of each device are described. Furthermore, the results for monitoring devices from clinical studies of goal-directed fluid and volume therapy which have been published will be discussed.A regular hydration status and compensated vascular filling are targets of perioperative fluid and volume management and, in parallel, represent precautions for sufficient stroke volume and cardiac output to maintain tissue oxygenation. The physiological and pathophysiological effects of fluid and volume replacement mainly depend on the pharmacological properties of the solutions used, the magnitude of the applied volume as well as the timing of volume replacement during surgery. In the perioperative setting surgical stress induces physiological and hormonal adaptations of the body, which in conjunction with an increased permeability of the vascular endothelial layer influence fluid and volume management. The target of haemodynamic monitoring in the operation room is to collect data on haemodynamics and global oxygen transport, which enable the anaesthetist to estimate the volume status of the vascular system. Particularly in high risk patients this may improve fluid and volume therapy with respect to maintaining cardiac output. A goal-directed volume management aiming at preventing hypovolaemia may improve the outcome after surgery. The objective of this article is to review the monitoring devices that are currently used to assess haemodynamics and filling status in the perioperative setting. Methods and principles for measuring haemodynamic variables, the measured and calculated parameters as well as clinical benefits and shortcomings of each device are described. Furthermore, the results for monitoring devices from clinical studies of goal-directed fluid and volume therapy which have been published will be discussed.

Intra- und postoperative Gerinnungsstörungen

Intra- und postoperative Blutungskomplikationen konnen bei Patienten mit vorbekannten Gerinnungsstorungen und Patienten mit leerer Blutungsanamnese auftreten. Diffenzialdiagnostisch muss prinzipiell bei jeder intra- und postoperativ auftretenden Blutung zwischen einer chirurgischen Blutungsursache und einer Gerinnungsstorung unterschieden werden.

Peri-operative Decreased cAMP Levels in Long-term Alcoholic Patients

Long-term alcoholic patients have a fivefold higher risk of post-operative bleeding complications compared with non-alcoholic individuals. Serotonin increases and cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) decrease platelet aggregation. We examined the platelet-rich plasma levels of these substances and agonist-induced platelet aggregation in long-term alcoholic patients before and after surgery. Thirty-three consecutive patients (13 long-term alcoholics and 20 non-alcoholics) scheduled for tumour resections of the upper digestive tract were included in the study. The levels of cAMP were significantly decreased before and after surgery in long-term alcoholic patients, but there were no significant differences in cGMP and serotonin levels in alcoholic compared with non-alcoholic patients. In contrast to previous studies, no significantly altered aggregation responses in long-term alcoholics were found. A possible explanation is decreased inhibition through diminished cAMP levels; cGMP and serotonin do not seem to influence peri-operative haemostasis.

51 – Alcoholic Cardiomyopathy

This chapter discusses the effects of alcohol consumption and cardiomyopathies. Congestive heart failure is a common finding and diagnosed in 1–2% of patients seeking medical assistance, and cardiomyopathies play a key role in this group of patients. Cardiomyopathies—a summary of diseases of different etiologies that have in common the involvement of the heart function. According to the World health organization/World Heart Federation with the classification task force of cardiomyopathies five different forms are recognized: dilated, hypertrophic, restrictive, right ventricular, and nonclassifiable cardiomyopathy. Chronic excessive consumption of alcohol is the major cause of nonischemic dilated cardiomyopathy in the Western world and accounts for up to one-third of all dilated cardiomyopathies. It seems that the duration of drinking is the key factor which promotes asymptomatic cardiomyopathy to congestive heart failure. Loss of myofibrils and disruption of the myofibrillary architecture are the leading findings. Apoptosis of cardiac muscle cells in vitro may contribute to the development of cardiomyopathy and heart failure. Studies on the acute effects of alcohol in the presence of coronary heart disease (CHD) suggest an exaggeration of exercise-related myocardial ischemia and impairment in ventricular function. There are some studies which suggest a protective effect of light ethanol consumption with regard to CHD.

Efficacy of non-specific hemostatic agents for reversal of prophylactic apixaban levels

Apixaban (Eliquis®) is a direct and competitive inhibitor of factor FXa that is approved for thrombosis prophylaxis after hip and knee replacement surgery, in non-valvular atrial fibrillation and venous thromboembolic events therapy [1]. In cases of severe hemorrhages there is no approved specific antidote available to reverse the effect of apixaban yet. Previous animal and in vitro studies [2, 3] with supratherapeutic concentrations of apixaban (200ng ml-1) have shown that activated prothrombin complex concentrate (aPCC) and recombinant factor VIIa (rFVIIa) have a greater effect in reversing the effect of apixaban than prothrombin complex concentrate (PCC). The effect of these non-specific hemostatic agents for reversal of apixaban concentrations measured in patients after prophylactic doses (maximum observed plasma concentration 62 ng ml-1 [4]) remains unclear.