Search

Background In children, the preoperative hydration status is an important part of the overall clinical assessment. The assumed preoperative fluid deficit is often routinely replaced during induction without knowing the child's actual fluid status. Aim We investigated the predictive value of the Pleth Variability Index as a measure of fluid responsiveness in spontaneously breathing anesthetized children. Methods Pleth Variability Index, stroke volume and Cardiac Index, measured by electrovelocimetry, mean blood pressure, and heart rate were recorded during anesthesia induction in 50 pediatric patients 15% (Positive predictive value 2.71 (95% CI: 1.4 to 5.2)). Only in fluid responders, the Pleth Variability Index decreased during passive leg raising, while stroke volume increased. Conclusions The Pleth Variability Index may be of additional value to predict fluid responsiveness in spontaneously breathing anesthetized children. A significant overlap in baseline Pleth Variability Index values between fluid responsive and nonfluid responsive patients does not allow a reliable recommendation as to a cut off value.

PLOS ONE 17(1), e0262110 (2022). doi:10.1371/journal.pone.0262110, Published by PLOS, San Francisco, California, US

BACKGROUND: Propofol and sufentanil target controlled infusion technology is used with increasing frequency. Drug interaction modelling, using clinical endpoints and processed electroencephalography helps determine optimal drug concentrations to assure adequate anesthesia. METHODS: Sixty patients were randomized to receive a constant concentration of sufentanil (0.25 ng/mL (Group S-0.25), 0.5 ng/mL (Group S-0.5), 0 ng/mL (Group S-0). Propofol was administered in steps of 0.5 mu g/mL, up to 4 mu g/mL. Processed EEG (Bispectral Index, Narcotrend Index) and auditory evoked potentials (composite A-Line autoregressive Index; cAAI), were recorded simultaneously. Sufentanil-propofol interaction was assessed by Probit - and nonlinear regression analysis. RESULTS : Sufentanil had a dose-dependent synergistic effect on the effect-site concentration of propofol (mu g/mL) associated with a 50% probability (EC50) of loss of responsiveness to verbal command (S-0: 2.84 mu g/mL, R-2 0.773; S-0.25: 1.95 mu g/mL, R-2 0.862; S-0.5: 1.48 mu g/mL, R-2 0.887) and noxious stimulation (S-0: 3.46 mu g/mL, R-2 0.626 mu g/mL; S-0.25: 2.17 mu g/mL, R-2 0.853; S-0.5: 1.69 mu g/mL, R-2 0.897). Non-linear regression analysis revealed a synergistic sufentanil effect on the propofol EC50 for BIS (S-0: 3.36 mu g/mL, R-2 0.79; S-0.25: 2.77 mu g/mL, R-2 0.86 mu g/mL; S-0.5: 2.6 mu g/mL, R-2 0.84), Narcotrend Index (S-0: 3.57 mu g/mL, R-2 0.66; S-0.25: 2.91 mu g/mL, R-2 0.70; S-0.5: 2.02 mu g/mL, R-2 0.51) and cAAI (S-0: 3.42 mu g/mL, R-2 0.59; S-0.25: 3.00 mu g/mL, R-2 0.63; S-0.5: 3.14 mu g/mL, R-2 0.59). CONCLUSIONS: Sufentanil has a synergistic effect on the clinically observed hypnotic properties of propofol. These findings apply also to the depth of hypnosis measured by the Bispectral Index, Narcotrend Index and cAAI.

Ein betrachtlicher Teil der Patienten, die sich dem Anasthesiologen im Rahmen der Pramedikationsvisite vorstellen, nimmt regelmasig Medikamente ein. Neben Arzneistoffen fur kardiovaskulare, pulmonale und metabolische Erkrankungen handelt es sich vielfach auch um antidepressiv, seltener um antipsychotisch wirksame Substanzen. Einige dieser Substanzen interagieren mit Anasthetika. Daher wird der Anasthesiologe im Rahmen der Pramedikationsvisite nicht selten mit der Frage nach der perioperativen Modifikation der psychiatrischen Dauermedikation konfrontiert. Weil das abrupte Absetzen antidepressiv oder antipsychotisch wirksamer Substanzen zum Wiederauftreten entsprechender Symptome und zu einem Entzugssyndrom fuhren kann, empfiehlt es sich grundsatzlich, die Entscheidung uber die perioperative Modifikation dieser Arzneitherapie gemeinsam mit dem behandelnden psychiatrischen Kollegen zu fallen. Soll die psychiatrische Medikation abgesetzt werden, ist auch der indikationsstellende Chirurg in die Risiko-Nutzen-Abwagung einzubeziehen, da der operative Eingriff aufgrund der langen Halbwertszeiten meist um mehrere Tage zu verschieben ist. Da in der Literatur keine prospektiv-randomisiert erhobenen Daten zur perioperativen Verordnung psychiatrischer Arzneistoffe vorliegen, muss sich diese Risiko-Nutzen-Abwagung neben physiologischen und pharmakologischen Grunduberlegungen auf publizierte Fallberichte und Expertenmeinungen berufen. Aus Anlass einer Leseranfrage an AINS zur perioperativen Verordnung von Opipramol werden nachfolgend die verfugbaren Daten zur perioperativen Verordnung bestimmter psychiatrischer Arzneimittel zusammengefasst, um dem Leser eine Entscheidungshilfe fur das Absetzen oder Weiterverordnen der praoperativen Dauermedikation bei psychiatrischen Erkrankungen an die Hand zu geben.

The purpose of the study was to investigate the evolution of central corneal thickness (CCT) in correlation to the intraocular pressure (IOP) in children with congenital glaucoma before and after glaucoma surgery.Nine eyes of five children (age 2 weeks to 6 months, mean 23 weeks) underwent trabeculotomy for congenital glaucoma. Corneal ultrasound pachymetry (PacScan 3000 AP, Technomed, Germany), tonometry using the Perkins tonometer, and slit-lamp examination (additionally to a clinical routine examination with retinoscopy, funduscopy, measurement of axial length and corneal diameter) were performed before and for at least 12 months after glaucoma surgery. In all children, corneal pachymetry and slit-lamp biomicroscopy--and whenever possible applanation tonometry--were performed without sedation or general anesthesia. If measurement of the IOP was not possible otherwise (in four of the five children), sedation with midazolam orally was used to measure the IOP at 2 weeks, 6 weeks, and 3 months after trabeculotomy, then every 3 months.Six of nine eyes had biomicroscopically clear corneas without visible corneal edema before trabeculotomy. In three eyes, a corneal edema was visible in at least one quadrant of the cornea. Regarding all eyes together, mean CCT was 651 +/- 138 microm before trabeculotomy; this decreased to 592 +/- 119 microm within 2 weeks after trabeculotomy. At 6 weeks and 3 months there was a further regression to 569.4 +/- 16 microm. Mean IOP was 18.6 +/- 7.5 mmHg before and decreased to 14.8 +/- 5.8 mmHg after glaucoma surgery. Regarding IOP data obtained under general anaesthesia, decrease of CCT was significantly correlated with decrease in IOP. There was no significant difference in the correlation between eyes with and without visible corneal edema.Corneal ultrasound pachymetry appears to be a valuable additional measure in the follow-up of infants and small children requiring glaucoma surgery.

Objective: To evaluate the effect of a miniaturized extracorporeal circulation system (MECC™System) compared to conventional extracorporeal circulation (ECC) regarding liver function in cardiac surgical patients. Methods: Double indicator dilution measurements were achieved by bolus injection of indocyanine green (ICG) for assessment of cardiac index (CI) and plasma disappearance rate of ICG (PDRig). Measurements were simultaneously performed preoperatively after induction of anaesthesia (T1), following admission on the ICU (T2) and 6 h postoperatively (T3). Results: CI and PDRig were markedly increased after cardiac surgery without significant differences between groups. The percentage increase in CI was significantly correlated to the percentage increase in PDRig in both groups. Conclusion: Liver function improved after cardiac surgery in both groups of patients, which may partly be explained by an increase in CI under mild inotrope support. Differences between the extracorporeal circuits with respect to PDRig appear to be minimal in a group of patients without pre-existing liver injury. Perfusion (2007) 22, 245—250.

Background Volatile anesthetics are frequently used during cardiopulmonary bypass (CPB) to maintain anesthesia. Uptake and elimination of the volatile agent are dependent on the composition of the oxygenator. This study was designed to evaluate whether the in vivo uptake and elimination of isoflurane differs between microporous membrane oxygenators containing a conventional polypropylene (PPL) membrane and oxygenators with a new poly-(4-methyl-1-pentene) (PMP) membrane measuring isoflurane concentrations in blood. Methods Twenty-four patients undergoing elective coronary bypass surgery with the aid of CPB were randomly allocated to one of four groups, using either one of two different PPL-membrane oxygenators for CPB or one of two different PMP-membrane oxygenators. During hypothermic CPB, 1% isoflurane in an oxygen-air mixture was added to the oxygenator gas inflow line (gas flow, 3 l/min) for 15 min. Isoflurane concentration was measured in blood and in exhaust gas at the outflow port of the oxygenator. Between-group comparisons were performed for the area under the curve (AUC) during uptake and elimination of the isoflurane blood concentrations, the maximum isoflurane blood concentration (C(max)), and the exhausted isoflurane concentration (F(E)). Results The uptake of isoflurane, expressed as AUC of isoflurane blood concentration and a function of F(E), was significantly reduced in PMP oxygenators compared to PPL oxygenators (P < 0.01). C(max) was between 8.5 and 13 times lower in the PMP-membrane oxygenator groups compared to the conventional PPL-membrane oxygenator groups (P < 0.01). Conclusions The uptake of isoflurane into blood via PMP oxygenators during CPB is severely limited. This should be taken into consideration in cases using such devices.

Following heart transplantation (HTx) in a 49-year old male, the patient’s haemodynamic situation deteriorated in the early postoperative period despite increasing doses of catecholamines. When transoesophageal echocardiography (TEE) showed a dilated right ventricle, but adequate left ventricular (LV) function, a right ventricular assist device (RVAD) was implanted to support the right ventricle of the failing graft. Evaluation of the resulting cardiac output (CO) of the left ventricle and, thus, assessment of the remaining right ventricular function in patients supported by a RVAD is of great clinical interest. In this situation, continuous measurement of LV function, enabling assessment of the remaining right ventricular function, can be performed by pulse contour analysis following initial calibration of the system by arterial thermodilution CO measurement via a left atrial catheter.

Apart from cardiovascular, pulmonary and metabolic drugs, many patients scheduled for surgery are taking antidepressive or antipsychotic drugs. Some of these psychiatric drugs may interfere with anesthetics. The anesthesiologist has to decide whether or not to continue the psychiatric medication during the perioperative period. Since the discontinuation of psychiatric drugs may lead to withdrawal syndromes, the decision should be made in accordance with the attending psychiatrist. Should the discontinuation of any psychiatric drug be recommended, it may be prudent to involve the attending surgeon in order to postpone the procedure, since the modification of psychiatric drugs may take several days.Prospective randomized data about the perioperative modification of psychiatric drugs are scarce. Thus, recommendations in this regard must rely on physiological and pharmacological principles, case reports and published expert opinions. In this article we use the available data to answer the question of a journal reader regarding the perioperative modification of Opipramol therapy for a 59-year-old patient scheduled for elective shoulder surgery.

IMPLICATIONS: The fluoride inhibition of mivacurium hydrolysis by pseudocholinesterase increases in hypothermia, but it will very rarely occur in clinical practice because it requires rather large fluoride concentrations (>50 micromol/L) and very low temperatures (

BACKGROUND AND OBJECTIVE Accurate assessment of a patient's volume status is an important goal for an anaesthetist. However, most variables assessing fluid responsiveness are either invasive or technically challenging. This study was designed to compare the accuracy of arterial pressure-based stroke volume variation (SVV) and variations in the pulse oximeter plethysmographic waveform amplitude as evaluated with the noninvasive calculated pleth variability index (PVI) with central venous pressure to predict the response of stroke volume index (SVI) to volume replacement in patients undergoing major surgery. METHODS We studied 20 patients scheduled for elective major abdominal surgery. After induction of anaesthesia, all haemodynamic variables were recorded immediately before (T1) and subsequent to volume replacement (T2) by infusion of 6% hydroxy-ethyl starch (HES) 130/0.4 (7 ml kg) at a rate of 1 ml kg min. RESULTS The volume-induced increase in SVI was at least 15% in 15 patients (responders) and less than 15% in five patients (nonresponders). Baseline SVV correlated significantly with changes in SVI (DeltaSVI; r = 0.80; P < 0.001) as did baseline PVI (r = 0.61; P < 0.004), whereas baseline values of central venous pressure showed no correlation to DeltaSVI. There was no significant difference between the area under the receiver operating characteristic curve for SVV (0.993) and PVI (0.973). The best threshold values to predict fluid responsiveness were more than 11% for SVV and more than 9.5% for PVI. CONCLUSION Although arterial pressure-derived SVV revealed the best correlation to volume-induced changes in SVI, the results of our study suggest that both variables, SVV and PVI, can serve as valid indicators of fluid responsiveness in mechanically ventilated patients undergoing major surgery.

Summary Background and objective: It has been demonstrated that volatile anaesthetics have cardioprotective properties during open-heart procedures, especially when administered continuously. European Council Directive 93/42/ EEC concerning medical devices bans the supplementary incorporation of anaesthetic vaporizers in the bypass circuit. Since the uptake of volatile anaesthetics via diffusion membrane oxygenators is severely reduced, it is hypothesized that clinically relevant concentrations of sevoflurane will remain in the patients’ blood following saturation with a volatile agent before start of cardiopulmonary bypass. This study was designed to compare conventional and diffusion membrane oxygenators regarding their in vivo elimination of sevoflurane. Methods: Twenty patients undergoing elective coronary bypass surgery were randomly allocated to two groups, either using a conventional polypropylene membrane oxygenator or a plasma-tight poly-(4-methyl-1-pentene) membrane oxygenator in a miniaturized extracorporeal circuit. Anaesthesia was maintained with sevoflurane, which was stopped at the start of cardiopulmonary bypass. During cardiopulmonary bypass, sevoflurane concentration was measured in blood and in the exhausted gas from the oxygenator. Results: The elimination of sevoflurane, expressed as the relative blood concentration, was significantly increased in polypropylene membrane oxygenators compared to poly-(4-methyl-1-pentene) membrane oxygenators. This resulted in an approximately threefold higher sevoflurane blood concentration in the poly-(4-methyl-1-pentene) group over the course of cardiopulmonary bypass. Conclusions: With the incorporation of a poly-(4-methyl-1-pentene) oxygenator in a miniaturized bypass circuit, relevant concentrations of a previously applied volatile agent can be maintained even without further supply throughout cardiopulmonary bypass. This might be an alternative approach to cardioprotection when sevoflurane cannot be administered through cardiopulmonary bypass.

Sir: A recently introduced device for measuring arterial pressure based cardiac output (COAP; FloTrac, Vigileo; Edwards Lifesciences, Irvine, Calif., USA) has been discussed as a less invasive alternative to the pulmonary artery catheter (PAC) for cardiac output (COPAC) assessment. To facilitate COAP assessment by arterial pulse waveform analysis without an external calibration mode, the system estimates individual arterial compliance according to the five-component model of Langewouters et al. [1] and compensates for changes in vascular tone by detecting characteristic alterations in the arterial pressure waveform. However, recent studies have demonstrated limited agreement between the intermittent bolus thermodilution COPAC measurement and COAP [2–4], probably caused by the calculation mode with which the used COAP algorithm (version 1.03) adjusts to changes in vascular resistance [4]. The response time to changes in vascular tone has been improved in a subsequent version of software (version 1.10) and the 10-min moving window for assessing vascular tone set to 1 min. The present investigator-blinded study was performed to evaluate the accuracy of the latest version of COAP software in a setting of postoperative cardiac surgery using COPAC as the method of reference. With approval of the institutional ethics committee and written informed consent by participants, we studied 20 postoperative cardiac surgical patients who underwent elective coronary artery bypass grafting (Table 1). Prior to surgery all patients received a radial arterial line and a 7.5-F PAC. Following admission to the intensive care unit the sensor was attached to the existing arterial line and connected to a Vigileo monitor for COAP assessment. COPAC measurements were performed every 2 h during mechanical ventilation and weaning from ventilation and after extubation COPAC to obtain at least seven values per patient. The average of three measurements randomly distributed over the respiratory cycle was calculated. COAP values were taken simultaneously at the end of bolus determinations and correspondingly averaged. Volume administration and inotropic support remained constant during measuring periods. Data acquisition was completed when the PAC or the arterial catheter was removed. A total of 158 coupled measurements were obtained. Bland–Altman analysis between COPAC and COAP for all values showed a mean bias and limits of agreement (LOA) of 0.01± 1.63 l/min, as displayed in Fig. 1a. The percentage error (± 1.96 SD of the bias/mean CO) between COPAC and COAP was 26.9%. Trend analysis between percentage changes in COPAC (∆ COPAC) and COAP (∆ COAP) for 138 consecutive measurements revealed a bias of 0.93% with LOA of ± 28.27%, as shown in Fig. 1b. Separate analysis for mean CO values of 6 l/min or less and of more than 6 l/min showed

Background Several techniques have been discussed as alternatives to the intermittent bolus thermodilution cardiac output (COPAC) measurement by the pulmonary artery catheter (PAC). However, these techniques usually require a central venous line, an additional catheter, or a special calibration procedure. A new arterial pressure-based cardiac output (COAP) device (FloTrac™, Vigileo™; Edwards Lifesciences, Irvine, CA, USA) only requires access to the radial or femoral artery using a standard arterial catheter and does not need an external calibration. We validated this technique in critically ill patients in the intensive care unit (ICU) using COPAC as the method of reference. Methods We studied 20 critically ill patients, aged 16 to 74 years (mean, 55.5 ± 18.8 years), who required both arterial and pulmonary artery pressure monitoring. COPAC measurements were performed at least every 4 hours and calculated as the average of 3 measurements, while COAP values were taken immediately at the end of bolus determinations. Accuracy of measurements was assessed by calculating the bias and limits of agreement using the method described by Bland and Altman. Results A total of 164 coupled measurements were obtained. Absolute values of COPAC ranged from 2.80 to 10.80 l/min (mean 5.93 ± 1.55 l/min). The bias and limits of agreement between COPAC and COAP for unequal numbers of replicates was 0.02 ± 2.92 l/min. The percentage error between COPAC and COAP was 49.3%. The bias between percentage changes in COPAC (ΔCOPAC) and percentage changes in COAP (ΔCOAP) for consecutive measurements was -0.70% ± 32.28%. COPAC and COAP showed a Pearson correlation coefficient of 0.58 (p < 0.01), while the correlation coefficient between ΔCOPAC and ΔCOAP was 0.46 (p < 0.01). Conclusion Although the COAP algorithm shows a minimal bias with COPAC over a wide range of values in an inhomogeneous group of critically ill patients, the scattering of the data remains relative wide. Therefore, the used algorithm (V 1.03) failed to demonstrate an acceptable accuracy in comparison to the clinical standard of cardiac output determination.

OBJECTIVE: Pump-driven extracorporeal gas exchange systems have been advocated in patients suffering from severe acute respiratory distress syndrome who are at risk for life-threatening hypoxemia and/or hypercapnia. This requires extended technical and staff support. DESIGN: We report retrospectively our experience with a new pumpless extracorporeal interventional lung assist (iLA) establishing an arteriovenous shunt as the driving pressure. SETTING: University hospital. PATIENTS: Ninety patients with acute respiratory distress syndrome. INTERVENTIONS: Interventional lung assist was inserted in 90 patients with acute respiratory distress syndrome. MEASUREMENTS AND MAIN RESULTS: Oxygenation improvement, carbon dioxide elimination, hemodynamic variables, and the amount of vasopressor substitution were reported before, 2 hrs after, and 24 hrs after implementation of the system. Interventional lung assist led to an acute and moderate increase in arterial oxygenation (Pao2/Fio2 ratio 2 hrs after initiation of iLA [median and interquartile range], 82 mm Hg [64-103]) compared with pre-iLA (58 mm Hg [47-78], p < .05). Oxygenation continued to improve for 24 hrs after implementation (101 mm Hg [74-142], p < .05). Hypercapnia was promptly and markedly reversed by iLA within 2 hrs (Paco2, 36 mm Hg [30-44]) in comparison with before (60 mm Hg [48-80], p < .05], which allowed a less aggressive ventilation. For hemodynamic stability, all patients received continuous norepinephrine infusion. The incidence of complications was 24.4%, mostly due to ischemia in a lower limb. Thirty-seven of 90 patients survived, creating a lower mortality rate than expected from the Sequential Organ Failure Assessment score. CONCLUSIONS: Interventional lung assist might provide a sufficient rescue measure with easy handling properties and low cost in patients with severe acute respiratory distress syndrome and persistent hypoxia/hypercapnia.

Accurate assessment of preload responsiveness is an important goal of the clinician to avoid deleterious volume replacement associated with increased morbidity and mortality in mechanically ventilated patients. This study was designed to evaluate the accuracy of simultaneously assessed stroke volume variation and pulse pressure variation using an improved algorithm for pulse contour analysis (PiCCO plus, V 5.2.2), compared to the respiratory changes in transoesophageal echo-derived aortic blood velocity (deltaVpeak), intrathoracic blood volume index, central venous pressure and pulmonary capillary wedge pressure to predict the response of stroke volume index to volume replacement in normoventilated cardiac surgical patients.We studied 20 patients undergoing elective coronary artery bypass grafting. After induction of anaesthesia, haemodynamic measurements were performed before and after volume replacement by infusion of 6% hydroxyethyl starch 200/0.5 (7 mL kg(-1) ) with a rate of 1 mL kg(-1) min(-1).Baseline stroke volume variation correlated significantly with changes in stroke volume index (deltaSVI) (r2 = 0.66; P0.05) as did baseline pulse pressure variation (r2 = 0.65; P0.05), whereas baseline values of deltaVpeak, intrathoracic blood volume index, central venous pressure and pulmonary artery wedge pressure showed no correlation to deltaSVI. Pulse contour analysis underestimated the volume-induced increase in cardiac index measured by transpulmonary thermodilution (P0.05).The results of our study suggest that stroke volume variation and its surrogate pulse pressure variation derived from pulse contour analysis using an improved algorithm can serve as indicators of fluid responsiveness in normoventilated cardiac surgical patients. Whenever changes in systemic vascular resistance are expected, the PiCCO plus system should be recalibrated.

BACKGROUND Extracorporeal lung assist has been proposed as an invasive measure in patients with acute respiratory distress syndrome (ARDS) when oxygenation is critically impaired. However, this technique generally requires high personnel and technical resources. We report on a new system, which is characterised by a short circuit arterio-venous shunt using arterio-venous pressure gradient as driving force (pumpless extracorporeal lung assist [pECLA]). PATIENTS AND METHODS In 30 patients with ARDS due to multitrauma, pneumonia or after surgery (p(a)O(2)/F(I)O(2)-ratio 67+/-23 mmHg) pECLA was established by insertion of cannulae to the femoral artery and vein followed by connection with a membrane gas exchanger. For this system, only "low dose" continuous heparin infusion is required. RESULTS Arterial oxygenation was acutely and significantly increased by pECLA (p(a)O(2)/F(I)O(2)=103+/-56 mmHg 2 h after begin) and carbon dioxide removal was markedly enhanced in 25 out of 30 patients (87%) allowing a lung protective ventilation strategy. The mean duration of pECLA therapy was 6.5 days, 15 patients (50%) died due to ARDS or non-ARDS related reasons. CONCLUSION pECLA represents a feasable and effective treatment in patients with severe ARDS. Compared with pump-driven systems pECLA is characterised by low costs and reduced personnel requirements. However, mortality remains high in patients suffering from severe ARDS despite newer treatment modalities.

Objectives: A higher incidence of pulmonary autograft dilatation is assumed in patients with ascending aortic dilatation and bicuspid aortic valve disease. To examine whether structural abnormalities are present in the ascending aorta as well as in the pulmonary trunk (PT) we specifically addressed molecular mechanisms and signalling pathways for aneurysm formation in ascending aortic aneurysms and PT of patients with different aortic valve pathology undergoing an extended Ross procedure. Methods: Wall segments resected from aortic aneurysms (20 patients, 7 bicuspid aortic valves BAV, and 13 tricuspid aortic valves TAV) and from PTs were submitted to analysis of leukocyte infiltration (immunohistochemistry), smooth muscle cell (SMC) apoptosis (in situ end-labelling of DNA-fragments TUNEL), and expression of death-promoting proteins perforin, granzyme B, Fas/FasL (immunoblotting). Results: Degenerative changes including rarefication and apoptosis of SMCs were significantly more severe in BAV than TAV disease (apoptotic index 9.2 ^ 3.2 vs. 11.9 ^ 6.2, P ¼ 0:02). Immunohistochemistry confirmed presence and activation of death-promoting mediators in aneurysmal tissue whereas pulmonary tissue displayed only few apoptotic cells, occasional Fas þ cells, rarely colocalized with FasL. By Western blot analysis extracts from BAV and TAV but not pulmonary artery wall contained appreciable amounts of perforin, granzyme B, and Fas/FasL. Conclusion: Aneurysm formation is associated with SMC apoptosis and local signal expression of activated cells in patients with bicuspid as well as TAV. The PT itself is not pathologically involved with only minor degenerative changes. Although the disease process in the aorta appeared to be more severe in patients with BAV, there was similarity of histological and molecular changes of the pulmonary artery wall in all patients. Dilation of the pulmonary autograft seems not to be the result of histopathological and biomolecular mechanisms in the PT. q 2004 Elsevier B.V. All rights reserved.

Assessment of cardiac performance and adequate fluid replacement of a critically ill patient are important goals of a clinician. We designed this study to evaluate the ability of stroke volume variation (SVV), derived from pulse contour analysis, and frequently used preload variables (central venous pressure and pulmonary capillary wedge pressure) to predict the response of stroke volume index and cardiac index to volume replacement in normoventilated cardiac surgical patients. We studied 20 patients undergoing elective coronary artery bypass grafting. After the induction of anesthesia, hemodynamic measurements were performed before (T1) and subsequent to volume replacement by infusion of 6% hydroxyethyl starch 200/0.5 (7 mL/kg) with a rate of 1 mL x kg(-1) x min(-1). Except for heart rate, all hemodynamic variables changed significantly (P < 0.01) after volume loading. Linear regression analysis between SVV at baseline (T1) and DeltaSVV after volume application showed a significant correlation (r = -0.97; P < 0.01), whereas linear regression analysis between SVV (T1) and percentage changes of stroke volume index (r = 0.19) and cardiac index (r = 0.17) did not reveal a significant relationship between variables. The results of our study suggest that SVV derived from pulse contour analysis cannot serve as an indicator of fluid responsiveness in normoventilated cardiac surgical patients.

In an open, uncontrolled pilot study, 5 men and 1 woman with suspected gram-negative sepsis were treated with a new whole-blood endotoxin adsorption system. Lipopolysaccharide (LPS) adsorption was carried out by hemoperfusion over high-affinity polymethacrylate-bound albumin (Fresenius Endotoxin Adsorber EN 500). All patients suffered from endotoxemia (>20 pg/ml LAL) and met at least two systemic inflammatory response syndrome (SIRS) criteria. Four patients suffered from pneumonia due to mechanical ventilation, one from peritonitis, and one from pneumonia and peritonitis. Endotoxin adsorption was very well tolerated, and efficient LPS removal was shown in all patients. Apache II score immediately before immunoadsorption was 23.5 and was 22.3 after the last treatment. All 6 critically ill patients improved substantially and were discharged from the intensive care unit. LPS whole blood immunoadsorption is a promising new method. No side effects have been observed thus far. A large controlled study to prove clinical efficacy in patients with severe sepsis is under way.

We have analysed the clinical agreement between two methods of continuous cardiac output measurement pulse contour analysis (PCCO) and a continuous thermodilution technique (CCO), were both compared with the intermittent bolus thermodilution technique (BCO). Measurements were performed in 26 cardiac surgical patients (groups 1 and 2, 13 patients each, with an ejection fraction > 45% and < 45%, respectively) at 12 selected times. During operation, mean differences (bias) between PCCO-BCO and CCO-BCO did not differ in either group. However, phenylephrine-induced increases in systemic vascular resistance (SVR) by approximately 60% resulted in significant differences. Significantly higher absolute bias values of PCCO-BCO compared with CCO-BCO were also found early after operation in the ICU. Thus PCCO and CCO provided comparable measurements during coronary bypass surgery. After marked changes in SVR, further calibration of the PCCO device is necessary.

Introduction Assessing cardiac preload and fluid responsiveness accurately is important when attempting to avoid unnecessary volume replacement in the critically ill patient, which is associated with increased morbidity and mortality. The present clinical trial was designed to compare the reliability of continuous right ventricular end-diastolic volume (CEDV) index assessment based on rapid response thermistor technique, cardiac filling pressures (central venous pressure [CVP] and pulmonary capillary wedge pressure [PCWP]), and transesophageal echocardiographically derived evaluation of left ventricular end-diastolic area (LVEDA) index in predicting the hemodynamic response to volume replacement.