T. von Spiegel

HZV-Bestimmung mittels transpulmonaler Thermodilution Eine Alternative zum Pulmonaliskatheter?

ZusammenfassungDie Messung des Herzzeitvolumens (HZV) ist zur Überwachung und Therapiesteuerung von Risikopatienten und Schwerstkranken häufig hilfreich. Die vorliegende Untersuchung beschreibt die HZV-Bestimmung mittels transpulmonaler Thermodilution (TPID) und vergleicht sie mit der herkömmlichen pulmonalarteriellen Thermodilution, wie sie unter Verwendung eines Pulmonaliskatheters klinisch breit angewendet wird. Bei sehr guter Übereinstimmung zwischen pulmonalarteriellem und transpulmonalem HZV (Bias=−4,7%±1,5% sem) über den gesamten untersuchten Altersbereich (0,5 bis 25,2 Jahre), besteht bei Doppelbestimmung auch eine vergleichbare Reproduzierbarkeit für die beiden Verfahren (SD=10.9% vs. 11,7%). Der geringeren Beeinflussung der HZV-Messung mittels TPID vom respiratorischen Zyklus steht die etwas größere Anfälligkeit gegenüber spontanen Temperaturschwankungen des Patienten entgegen. Im Gegensatz zur respiratorischen Abhängigkeit der pulmonalarteriellen Thermodilution kann die Anfälligkeit der TPID gegenüber diesen Temperaturschwankungen jedoch durch eine höhere Indikatordosierung weiter reduziert werden. Die zusätzlichen Einsatzmöglichkeiten in der pädiatrischen Anästhesie und Intensivmedizin, die prinzipiell geringere Invasivität und niedrigere Kosten sind Vorteile dieser Methode. Sie kann aber nicht bei allen klinischen Fragestellungen den Pulmonaliskatheter ersetzen.AbstractCardiac output measurements are often helpful in the management of critically ill patients and high risk-patients. In this study an alternative technique for measurement of cardiac output by the transpulmonary indicator dilution technique (TPID) was evaluated in comparison to conventional thermodilution using a pulmonary artery catheter. With TPID, a thermistor-tipped catheter (the smallest available is 1.3 F) is placed in the aorta via a femoral artery introducer. Thus, TPID can also be used in very small children in whom placement of a pulmonary artery catheter may be difficult or even impossible. In principle, TPID is less invasive since the possible complications of the pulmonary catheters are avoided. We investigated the accuracy and reproducibility of transpulmonary thermodilution in patients over a broad range in age and body surface. Methods. Following approval by the ethics committee and written consent, the data were obtained from 21 patients without a circulatory shunt undergoing diagnostic heart catheterization. The patients were between 0.5 and 25.2 years old, their body surface between 0.35 and 1.89 m2. Measurements were performed in duplicate with bolus injections of ice-cold normal saline (0.15 ml/kg), randomly spread over the respiratory cycle. In total 48 thermodilution curves were measured simultaneously in the pulmonary artery and in the aorta. Thermodilution curves were monoexponentially extrapolated for elimination of recirculation and cardiac output was calculated with a standard Stewart Hamilton procedure. Results. The amplitude of the typical arterial thermodilution curve shows a smaller and more delayed course than the pulmonary artery thermodilution curve. There was a very good correlation between the values found by pulmonary and TPID cardiac output measurements (R=0.968). There was a slightly smaller cardiac output value measured by the TPID (Bias=−4.7±1.5% sem) The reproducibility of duplicate measurements with the two methods were nearly the same, the standard deviation of the difference was 10.9% for the pulmonary thermodilution method and 11.7% for TPID. Discussion. TPID gives an alternative technique for measurement of cardiac output. We showed over a broad range in age and body surface a very good correlation with thermodilution measurements in the pulmonary artery. The slightly smaller values for TPID are explained by early recirculation, for clinical purposes the difference is negligible. However, the reproducibility of a method is clinically very important. Both methods showed in duplicate measurements basically the same reproduciblity. The disadvantage of TPID in being more sensitive to baseline alteration is counterbalanced by less respiratory variability in comparison to the conventional thermodilution technique. However, by increasing the amount of injected indicator (i.e., 0.2 ml/kg≅15 ml in an adult) it is possible to reduce the effect of baseline alteration. By using fiberoptic catheters it is even possible to use TPID as double-indicator dilution technique to measure intrathoracic blood volume (ITBV) and extravascular lung water (EVLW). We conclude that in many patients TPID might be an attractive, less invasive and reliable alternative to conventional cardiac output measurement by pulmonary artery catheter.

Endotoxin inhibits heat shock protein 70 (HSP70) expression in peripheral blood mononuclear cells of patients with severe sepsis

Objective: To investigate the ex vivo endotoxin-inducible heat shock protein 70 (HSP70) expression in the peripheral blood mononuclear cells (PBMC) of patients with severe sepsis in order to assess the capacity of this potentially protective response during systemic inflammation. Design: Prospective observational study in consecutive patients with severe sepsis and healthy blood donors. Setting: Surgical intensive care unit in a university hospital. Patients and participants: Eleven patients with the diagnosis of severe sepsis, one patient who had recovered from severe sepsis and 13 healthy blood donors. Interventions: None. Measurements and results: We studied the inducibility of HSP70 expression in the PBMC of patients with severe sepsis and healthy blood donors ex vivo. Human whole blood was incubated with variable lipopolysaccharide (LPS from Salmonella minnesota Re 595) concentrations (0; 0.1; 10; 100 ng/ml) for different periods of time (0.5; 2; 4; 10 h). The PBMC were separated by Ficoll density gradient and then disrupted by hypotonic lysis. HSP70 was measured by means of enzyme-linked immunosorbent assay (ELISA). We found a LPS dose- and time-dependent inhibition of ex vivo HSP70 expression in the PBMC of both patients with severe sepsis and healthy individuals. However, the levels of HSP70 expression in patients were significantly lower compared to those of healthy individuals at all LPS concentrations and incubation times. On average, HSP70 expression in the PBMC of healthy controls was 2.8 (range 1.2–3.9) times higher than in patients. HSP70 expression was inducible by thermal heat shock in the PBMC of both patients and healthy individuals. Conclusions: Endotoxin inhibits HSP70 expression in PBMC ex vivo. In vivo, the suppression of HSP70 expression induced by endotoxin and high levels of proinflammatory cytokines may contribute to the cellular dysfunction of immunocompetent cells concerning antigen presentation, phagocytosis and antibody production associated with decreased resistance to infectious insults during severe sepsis.

Perioperative monitoring of indocyanine green clearance and plasma disappearance rate in patients undergoing liver transplantation.

AbstractIntroduction. Indocyanine green (ICG) elimination tests have been repeatedly suggested as an early predictor of graft function in patients with liver transplantation. Conventionally, ICG clearance (ClICG) is measured by a series of blood samples with subsequent laboratory analysis. More recently bedside techniques have become available to measure ICG concentrations in vivo and in addition to ClICG, the plasma disappearance rate of ICG (PDRICG) is increasingly being used. The aim of this study was to assess and to compare the normal time courses of ClICG and PDRICG in liver transplant recipients. Methods. ClICG and PDRICG were measured perioperatively and at various times up to 24 h after liver transplantation. The bedside transpulmonary indicator dilution technique with an arterial fiberoptic-thermistor catheter was used to assess the ICG concentration time curve together with total circulating blood volume (Vd circ). Results. Similar patterns of the time courses of ClICG and PDRICG with a fast recovery of ICG elimination in the early reperfusion period were observed. Compared to healthy subjects, ClICG was supranormal and PDRICG was slightly subnormal. In this study, Vd circ was increased at baseline and remained increased during surgery. Conclusions. PDRICG and ClICG are well suited to monitor onset and maintenance of graft function in patients undergoing liver transplantation. The PDRICG values measured tend to be relatively lower than ClICG because of an increased blood volume in these patients. By knowing these differences it is justified to monitor liver function in a very simple manner with PDRICG.ZusammenfassungEinleitung. Indozyaningrün (ICG)-Eliminationstests wurden verschiedentlich als Frühindikator der Funktion des Spenderorgans nach einer Lebertransplantation empfohlen. Konventionell wird die ICG-Clearance (ClICG) aus einer Reihe von Blutproben in nachfolgenden Laboruntersuchungen bestimmt. Inzwischen sind aber auch Methoden verfügbar, die die Messung von ICG-Konzentrationen in vivo erlauben, sodass zunehmend die Plasmaverschwinderate von ICG (PDRICG) bestimmt wird. Ziel der vorliegenden Untersuchung war die Messung und der Vergleich der Zeitverläufe von ClICG und PDRICG bei Lebertransplantierten. Methodik. ClICG und PDRICG wurden perioperativ und bis 24 h postoperativ zu vorgegebenen Zeitpunkten bestimmt. Mit der Doppelindikator-Verdünnungstechnik und unter Verwendung eines arteriellen Fiberoptik-Thermistor-Katheters wurden die ICG-Konzentration-Zeit-Verläufe und das totale zirkulierende Blutvolumen (Vd circ) berechnet. Ergebnisse. Die Zeitverläufe der ClICG und der PDRICG– mit einer raschen Aufnahme der ICG-Elimination in der frühen Reperfusionsphase – waren ähnlich. Im Vergleich zu gesunden Probanden war die ClICG supranormal, die PDRICG jedoch leicht erniedrigt. Vd circ war bereits präoperativ erhöht und blieb auch intraoperativ supranormal. Schlussfolgerung. PDRICG und ClICG sind gut geeignet, um die Aufnahme und den Verlauf der Funktion einer Transplantatleber zu beurteilen. Die gemessene PDRICG ist wegen des erhöhten Blutvolumens dieser Patienten relativ gesehen niedriger als die ClICG. Bei Kenntnis dieser Unterschiede ist es gerechtfertigt, die Leberfunktion nach einer Transplantation mit der wenig aufwendigen Messung der PDRICG zu überwachen.

Antibiotikatherapie bei operativen Intensivpatienten

The development of resistance by infective bacterial species is an incentive to reconsider the indications and administration of available antibiotics. Correct recognition of the indications and duration of therapy are particularly important for the use of highly potent substances in the intensive care situation. There has as yet been no clinical chemical parameter which is capable of specifically distinguishing a bacterial infection from a viral or non-infectious inflammatory reaction, but it now appears that procalcitonin (PCT) offers this possibility. The present study was intended to clarify whether PCT can be used to guide antibiotic therapy in surgical intensive care patients. A total of 110 patients in a surgical intensive care ward receiving antibiotic therapy after confirmed infection or a high grade suspicion of infection were enrolled in this study. In 57 of these patients a new decision was reached each day as to whether the antibiotic therapy should be continued after daily PCT determination and clinical assessment. The control group consisted of 53 patients with a standardized duration of antibiotic therapy over 8 days. Demographic and clinical data were comparable in both groups. However, in the PCT group the duration of antibiotic therapy was significantly shorter compared to controls (5.9+/-1.7 vs. 7.9+/-0.5 days, p<0.001) without unfavorable effects on clinical outcome.

Effects of induction of anaesthesia with sufentanil and positive-pressure ventilation on the intra- to extrathoracic volume distribution

BACKGROUND AND OBJECTIVE Induction of general anaesthesia in combination with positive-pressure ventilation is often associated with a significant decrease of arterial pressure. A decreased preload may contribute to this phenomenon. The aim was to investigate whether a change in cardiac filling occurs following the induction of general anaesthesia with sufentanil under typical clinical conditions. METHODS Fifteen patients scheduled for elective coronary bypass grafting were studied immediately before surgery. In addition to standard monitors, a transpulmonary double-indicator dilution technique measured in vivo intrathoracic blood volume, global end-diastolic volume and total circulating blood volume. For induction of anaesthesia 2 microg kg(-1) sufentanil was given. Measurements were performed awake and after the induction of anaesthesia, intubation and mechanical ventilation of the lungs. RESULTS To maintain arterial pressure during the induction period within -20% of baseline pressure, on average 22 +/- 6mLkg(-1) crystalloids and 8 +/- 6mLkg(-1) colloids were given. Despite these amounts of fluid, cardiac filling was decreased, whereas circulating blood volume increased significantly. Both central venous pressure and pulmonary capillary wedge pressure increased. CONCLUSIONS Induction of general anaesthesia with positive-pressure ventilation is regularly associated with a blood volume shift from intra- to extrathoracic compartments. Even in low-dose opioid monoanaesthesia with sufentanil--often regarded as relatively inert in haemodynamic terms--the phenomenon could be demonstrated as the primary cause of the often-observed decrease of arterial pressure. It seems, therefore, rationally justified to restore cardiac filling by generous administration of intravenous fluids, at least in patients with unaffected cardiac pump function. During induction of anaesthesia, central venous pressure and pulmonary capillary wedge pressure do not reliably indicate cardiac filling.

Asthma bronchiale und chronisch obstruktive Lungenerkrankung mit akuter Exazerbation

Chronic obstructive pulmonary disease (COPD) and bronchial asthma are the most common causes of obstructive pulmonary diseases and acute dyspnoea. In the preclinical emergency situation a distinction between bronchial asthma and exacerbated COPD is difficult because symptoms are similar. Although the preclinical measures differ only marginally, a differential diagnosis from other causes of respiratory obstruction and acute dyspnoea, such as cardiac decompensation, anaphylaxis, aspiration of foreign bodies, tension pneumothorax and inhalation trauma is necessary because alternative treatment options are required. In the treatment of COPD and bronchial asthma inhalative bronchodilatory beta(2)-mimetics are the first choice especially for serious obstructive emergencies because there is an unfavorable relationship between effect and side-effects for the intravenous route. Dosable aerosols, nebulization and if necessary, continuous nebulization, are appropriate application forms even for serious obstructive crises with the need of a respirator. In these cases a minimal inspiratory flow in patients is not required. Theophylline only plays a minor role to beta(2)-mimetics and anticholinergics as a bronchodilator in asthma and COPD guidelines, even in serious obstructive diseases. For severe asthma attacks the administration of magnesium is a possible additional option. Systemic intravenous administration of steroids has an anti-inflammatory effect and for this reason is the second column of treatment for both diseases. Invasive ventilation remains a last resort to ensure respiratory function and indications for this are given in patients with clinical signs of impending exhaustion of breathing.ZusammenfassungAsthma bronchiale und chronisch obstruktive Lungenerkrankung („chronic obstructive pulmonary disease“, COPD) sind die häufigsten pulmonalen Ursachen von Atemwegsobstruktion und akuter Dyspnoe. In der präklinischen Notfallsituation ist die Differenzialdiagnostik bei ähnlichen klinischen Symptomen schwierig. Obwohl die präklinischen zu treffenden Maßnahmen sich nur marginal unterscheiden, ist die differenzialdiagnostische Abgrenzung zu anderen Ursachen von Atemwegsobstruktion und akuter Dyspnoe, wie kardiale Dekompensation, Anaphylaxie, Fremdkörperaspiration, Spannungspneumothorax und Inhalationstrauma, essenziell, denn ein abweichendes therapeutisches Vorgehen ist erforderlich. Für die Behandlung obstruktiver Notfälle bei Asthma bronchiale und COPD sind inhalative β2-Mimetika Medikamente der ersten Wahl, da sich i.v.-verabreichte β2-Mimetika durch eine ungünstigere Relation von Wirkeffekt zu Nebenwirkungsrate auszeichnen. Die Verneblung von Bronchodilatatoren ist – auch bei schweren sowie beatmungspflichtigen obstruktiven Krisen – eine geeignete Applikationsform, da ein inspiratorischer Mindestfluss durch den Patienten nicht erforderlich ist. Theophyllin als bronchodilatatorisch wirksame Substanz erhält laut Asthma- und COPD-Leitlinie selbst bei schweren Atemwegsobstruktionen erst nach β2-Mimetika- und Anticholinergikagabe eine nachgeordnete Empfehlung zur Anwendung. Für schwere Asthmaanfälle besteht die Möglichkeit der Magnesiumverabreichung als Zusatzoption. Die systemische i.v.-Gabe von Steroiden wirkt antinflammatorisch und stellt damit bei beiden Erkrankungen die zweite Säule der Behandlung dar. Die invasive Beatmung bleibt letztes Mittel zur Sicherung der respiratorischen Funktion, deren Indikation ergibt sich bei klinischen Anzeichen einer drohenden Erschöpfung der Atmung.AbstractChronic obstructive pulmonary disease (COPD) and bronchial asthma are the most common causes of obstructive pulmonary diseases and acute dyspnoea. In the preclinical emergency situation a distinction between bronchial asthma and exacerbated COPD is difficult because symptoms are similar. Although the preclinical measures differ only marginally, a differential diagnosis from other causes of respiratory obstruction and acute dyspnoea, such as cardiac decompensation, anaphylaxis, aspiration of foreign bodies, tension pneumothorax and inhalation trauma is necessary because alternative treatment options are required. In the treatment of COPD and bronchial asthma inhalative bronchodilatory β2-mimetics are the first choice especially for serious obstructive emergencies because there is an unfavorable relationship between effect and side-effects for the intravenous route. Dosable aerosols, nebulization and if necessary, continuous nebulization, are appropriate application forms even for serious obstructive crises with the need of a respirator. In these cases a minimal inspiratory flow in patients is not required. Theophylline only plays a minor role to β2-mimetics and anticholinergics as a bronchodilator in asthma and COPD guidelines, even in serious obstructive diseases. For severe asthma attacks the administration of magnesium is a possible additional option. Systemic intravenous administration of steroids has an anti-inflammatory effect and for this reason is the second column of treatment for both diseases. Invasive ventilation remains a last resort to ensure respiratory function and indications for this are given in patients with clinical signs of impending exhaustion of breathing.

Asthma bronchiale und chronisch obstruktive Lungenerkrankung mit akuter Exazerbation@@@Bronchial asthma and chronic obstructive pulmonary disease with acute exacerbation: Präklinische Differenzialdiagnostik und Notfalltherapie@@@Preclinical differential diagnostic and emergency treatment

Chronic obstructive pulmonary disease (COPD) and bronchial asthma are the most common causes of obstructive pulmonary diseases and acute dyspnoea. In the preclinical emergency situation a distinction between bronchial asthma and exacerbated COPD is difficult because symptoms are similar. Although the preclinical measures differ only marginally, a differential diagnosis from other causes of respiratory obstruction and acute dyspnoea, such as cardiac decompensation, anaphylaxis, aspiration of foreign bodies, tension pneumothorax and inhalation trauma is necessary because alternative treatment options are required. In the treatment of COPD and bronchial asthma inhalative bronchodilatory beta(2)-mimetics are the first choice especially for serious obstructive emergencies because there is an unfavorable relationship between effect and side-effects for the intravenous route. Dosable aerosols, nebulization and if necessary, continuous nebulization, are appropriate application forms even for serious obstructive crises with the need of a respirator. In these cases a minimal inspiratory flow in patients is not required. Theophylline only plays a minor role to beta(2)-mimetics and anticholinergics as a bronchodilator in asthma and COPD guidelines, even in serious obstructive diseases. For severe asthma attacks the administration of magnesium is a possible additional option. Systemic intravenous administration of steroids has an anti-inflammatory effect and for this reason is the second column of treatment for both diseases. Invasive ventilation remains a last resort to ensure respiratory function and indications for this are given in patients with clinical signs of impending exhaustion of breathing.ZusammenfassungAsthma bronchiale und chronisch obstruktive Lungenerkrankung („chronic obstructive pulmonary disease“, COPD) sind die häufigsten pulmonalen Ursachen von Atemwegsobstruktion und akuter Dyspnoe. In der präklinischen Notfallsituation ist die Differenzialdiagnostik bei ähnlichen klinischen Symptomen schwierig. Obwohl die präklinischen zu treffenden Maßnahmen sich nur marginal unterscheiden, ist die differenzialdiagnostische Abgrenzung zu anderen Ursachen von Atemwegsobstruktion und akuter Dyspnoe, wie kardiale Dekompensation, Anaphylaxie, Fremdkörperaspiration, Spannungspneumothorax und Inhalationstrauma, essenziell, denn ein abweichendes therapeutisches Vorgehen ist erforderlich. Für die Behandlung obstruktiver Notfälle bei Asthma bronchiale und COPD sind inhalative β2-Mimetika Medikamente der ersten Wahl, da sich i.v.-verabreichte β2-Mimetika durch eine ungünstigere Relation von Wirkeffekt zu Nebenwirkungsrate auszeichnen. Die Verneblung von Bronchodilatatoren ist – auch bei schweren sowie beatmungspflichtigen obstruktiven Krisen – eine geeignete Applikationsform, da ein inspiratorischer Mindestfluss durch den Patienten nicht erforderlich ist. Theophyllin als bronchodilatatorisch wirksame Substanz erhält laut Asthma- und COPD-Leitlinie selbst bei schweren Atemwegsobstruktionen erst nach β2-Mimetika- und Anticholinergikagabe eine nachgeordnete Empfehlung zur Anwendung. Für schwere Asthmaanfälle besteht die Möglichkeit der Magnesiumverabreichung als Zusatzoption. Die systemische i.v.-Gabe von Steroiden wirkt antinflammatorisch und stellt damit bei beiden Erkrankungen die zweite Säule der Behandlung dar. Die invasive Beatmung bleibt letztes Mittel zur Sicherung der respiratorischen Funktion, deren Indikation ergibt sich bei klinischen Anzeichen einer drohenden Erschöpfung der Atmung.AbstractChronic obstructive pulmonary disease (COPD) and bronchial asthma are the most common causes of obstructive pulmonary diseases and acute dyspnoea. In the preclinical emergency situation a distinction between bronchial asthma and exacerbated COPD is difficult because symptoms are similar. Although the preclinical measures differ only marginally, a differential diagnosis from other causes of respiratory obstruction and acute dyspnoea, such as cardiac decompensation, anaphylaxis, aspiration of foreign bodies, tension pneumothorax and inhalation trauma is necessary because alternative treatment options are required. In the treatment of COPD and bronchial asthma inhalative bronchodilatory β2-mimetics are the first choice especially for serious obstructive emergencies because there is an unfavorable relationship between effect and side-effects for the intravenous route. Dosable aerosols, nebulization and if necessary, continuous nebulization, are appropriate application forms even for serious obstructive crises with the need of a respirator. In these cases a minimal inspiratory flow in patients is not required. Theophylline only plays a minor role to β2-mimetics and anticholinergics as a bronchodilator in asthma and COPD guidelines, even in serious obstructive diseases. For severe asthma attacks the administration of magnesium is a possible additional option. Systemic intravenous administration of steroids has an anti-inflammatory effect and for this reason is the second column of treatment for both diseases. Invasive ventilation remains a last resort to ensure respiratory function and indications for this are given in patients with clinical signs of impending exhaustion of breathing.

Antibiotikatherapie bei operativen Intensivpatienten@@@Antibiotic treatment of surgical intensive care patients: Prokalzitonin zur Steuerung der Therapiedauer@@@Procalcitonin to guide duration of therapy

The development of resistance by infective bacterial species is an incentive to reconsider the indications and administration of available antibiotics. Correct recognition of the indications and duration of therapy are particularly important for the use of highly potent substances in the intensive care situation. There has as yet been no clinical chemical parameter which is capable of specifically distinguishing a bacterial infection from a viral or non-infectious inflammatory reaction, but it now appears that procalcitonin (PCT) offers this possibility. The present study was intended to clarify whether PCT can be used to guide antibiotic therapy in surgical intensive care patients. A total of 110 patients in a surgical intensive care ward receiving antibiotic therapy after confirmed infection or a high grade suspicion of infection were enrolled in this study. In 57 of these patients a new decision was reached each day as to whether the antibiotic therapy should be continued after daily PCT determination and clinical assessment. The control group consisted of 53 patients with a standardized duration of antibiotic therapy over 8 days. Demographic and clinical data were comparable in both groups. However, in the PCT group the duration of antibiotic therapy was significantly shorter compared to controls (5.9+/-1.7 vs. 7.9+/-0.5 days, p<0.001) without unfavorable effects on clinical outcome.