Anaesthesiologie und Reanimation最新文献

The new method of controlled cyclophotocoagulation of the eye is an example of a short, non-invasive procedure that is still too painful to be done under local anaesthesia alone. The risks associated with general anaesthesia, on the other hand, seem to be inappropriately high compared to the risks associated with the procedure itself. Therefore, for this procedure, we combined local anaesthesia with 0.5% proxymetacain and 10% cocaine and sedation with propofol and analgesia with piritramide. Our experiences with this method have been positive. We have applied our method to 42 patients undergoing a total of 53 procedures and we have seen no major changes in haemodynamics and only two cases of momentary slight ventilatory depression. Therefore, we conclude that our method of managed anaesthesia care is suitable for patients undergoing cyclophotocoagulation of the eye, combining patient comfort with haemodynamic stability and minimal risk for the patient.

Machine autotransfusion using cell-saver is a well-established method of saving homologous blood during extensive surgical procedures. The processing of blood may induce the initiation of lipid peroxidation (LPO) with the release of hepatotoxic products. A series of 42 patients undergoing primary (n = 20) or revision (n = 22) hip arthroplasty comprised the study group. Patients received an average of 1,260 ml of autologous blood and 2.2 units of homologous packed cells. The concentration of thiobarbituric acid reactive substances (TBARS) as LPO metabolites was measured in the patients' plasma, in the autologous packed cells as well as in the supernatants of the cell-saver-processed blood. Additionally, parameters of iron metabolism, haemoglobin levels, haematocrit as well as the activities of so-called liver enzymes aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltranspeptidase and cholinesterase were determined. An initiation of LPO was detectable during the process of machine autotransfusion, but this took place mainly ex vivo. High concentrations of TBARS were detectable in the supernatants after cell-separation processing. We observed a decline in haemoglobin concentration and haematocrit during the perioperative period. Postoperatively, we found a significant iron deficiency as a consequence of the perioperative blood loss. There was not sufficient evidence of a postoperative liver disorder induced by toxic metabolites of LPO. To sum up, there is only a low contamination of the organism with LPO products during the process of machine autotransfusion. Therefore, an induction of liver damage seems to be improbable.

In the literature there is only little information about the influence of hyperoxia on cerebral metabolic parameters. The aim of our study was to examine the effect of increased inspiratory oxygen concentrations on parameters of brain metabolism in elective neurosurgical patients. Ten patients undergoing an elective craniotomy for brain tumour resection were included in the study. The inspiratory oxygen concentration was raised at intervals of 15 minutes from 0.4 to 0.6 to 1.0 before opening the skull under "relative steady state conditions". At five defined measuring points, a blood gas analysis and an analysis of lactate and glucose levels were performed from arterial and jugularvenous blood. The lactate oxygen index (LOI), the arterio-jugularvenous lactate difference (AJDL) and the oxygen content of the arterial (caO2) and jugularvenous (cjO2) blood were calculated. Under increasing levels of FiO2, one can see an increase in sjO2, of jugularvenous oxygen tension (pjO2) and in oxygen content (cjO2). The most important result is the significant decrease (10% from baseline) in jugularvenous lactate at FiO2 1.0, while arterial lactate did not change significantly nor did the following parameters: paCO2, pjCO2, LOI, modified LOI, arterial and jugularvenous glucose. Hyperoxia causes a possible shift to aerobic metabolic situation in the brain reflected by decreased jugularvenous lactate.

The anaesthetic-saving property of clonidine has often been reported. In our own prospective, randomized study, in which the depth of anaesthesia was controlled by using spectral edge frequency (target-SEF90 = 10 Hz) and clinical parameters, we confirmed the anaesthetic-saving property only for fentanyl (-20%). On the other hand, there was no difference in MAC-sevoflurane values between the groups in keeping a steady target-SEF. For this reason, we analysed the stored pEEG data with regard to clonidine-specific effects. Twenty-eight patients were included in our study. The patients were randomly treated preoperatively with an infusion of 4 micrograms/kg KG Clonidine (clonidine group) or a placebo (placebo group). For anaesthesia, a standardized procedure with fentanyl, propofol, rocuronium, N2O/O2/sevoflurane was performed. The depth of anaesthesia was controlled by using SEF90 and clinical parameters. SEF90, SEF50 and the EEG power-spectrum were analysed over a five-minute period in the steady state of anaesthesia without surgical manipulation. Both placebo and the clonidine showed comparable values for SEF90 (9.9 +/- 1 vs. 10.7 +/- 0.9 Hz). On the other hand, there were differences in the SEF50 values between the groups (3.3 +/- 0.7 vs. 6.4 +/- 2.2 Hz). In the clonidine group, relative alpha-power was higher than in the placebo group (36.3 +/- 15.8 vs. 16.8 +/- 8.8%). Parallel to this effect, there was a reduction in relative delta-power in the clonidine group (47.6 +/- 15.2 vs. 65.4 +/- 9.1%). The described EEG effects on the power-spectrum inevitably influence SEF50 and SEF90. In our opinion, SEF50 is not a powerful predictor of depth of anaesthesia, when anaesthesia is performed in the way described. By performing this variation of balanced anaesthesia and co-medication with clonidine, higher values of SEF90 (11-14 Hz) seem to be adequate for surgical manipulation.

It has been discussed by other authors that clinically relevant mistakes can occur in the measurement of invasive blood pressure. For this reason, we investigated all pressure lines used in our hospital. Our studies showed that exact measurement of invasive blood pressure using fluid-filled pressure measuring systems is not possible in the arterial, venous or pulmonal-arterial areas. Iatrogen mistakes should be excluded by working carefully. Exact knowledge of the physical qualities and the dynamic response of the fluid-filled pressure line used is required for judging the measuring accuracy. In clinical practice, measurement errors can amount to 40%. An acknowledged method to verifying errors is the Gabarith system developed by Billiet and Colardyn, which can determine the extent of the biggest-possible error after investigating the pressure line. A reduction of measurement error to below 2% can be achieved by carefully combining the individual components of the measuring system and, if necessary, by using an industrially-produced damping device (resonance overshoot eliminator [R.O.S.E.]). In this way, standardized measuring systems can be made available for clinical practice.

The 25th anniversary of the foundation of the journal "Anaesthesiology und Reanimation" seems to be a good occasion, first of all, to look back at the special situation regarding the opportunities open to East German anaesthetists for publishing anaesthesiological papers before and after the Berlin Wall was built and then to give a review of the history of this journal. As the author's own publication list shows, East Germans could publish papers in West German journals without any problems before a major reform of the universities, bringing drastic changes, was introduced in East Germany in 1969. It became practically impossible to publish papers in West German journals because the "Directorates of International Relations", which had been installed at all universities in 1969, supervised the entire correspondence with persons and institutions in all foreign countries, in particular West Germany, the other West European countries and the countries of North and South America. Thus, East German anaesthetists were forced to publish in non-anaesthesiological East German journals because there was no journal of anaesthesiology in East Germany until "Anaesthesiologie und Reanimation" was founded as journal of the "Society of Anaesthesiology and Reanimation of the GDR" in 1976. The problems arising from the introduction of this journal under socialist conditions, including political pressure and control through the "General Secretariat of the Medical Scientific Societies of the Ministry of Health of the GDR" as well as technical problems with the publisher and the printers, are described. In spite of all these problems, which were overcome by the editor-in-chief with the aid of his colleagues on the editorial board and the scientific advisory council, this journal was initially published with a circulation of 1,200 copies in 1976 and its circulation increased to 1,600 copies in 1989. The journal proved to be of great benefit to East German anaesthetists and anaesthetists from other East European countries. It was included in an international exchange programme of anaesthesiological journals, which was particularly helpful for East German anaesthetists because they could not subscribe to West German, West European or American journals due to a lack of hard currency. The international exchange of the journal led to an increasing number of authors from West Germany and other West European countries and even from the USA and Canada who published papers in "Anaesthesiology und Reanimation". The "silent revolution" in 1989 brought new problems. The journal was primarily an organ of the "Society of Anaesthesiology and Intensive Therapy of the GDR", but with the end of the GDR, this society was dissolved on 23rd October 1990. Fortunately, "Anaesthesiologie und Reanimation" was taken over by the "German Society of Anaesthesiology and Intensive Medicine" as an organ of this society, in which the former members of the East German society were gathered. The n

During transurethral resection of the prostate (TURP), systemic influx of hypotonic irrigating fluid is a life-threatening event. Its occurrence can lead to TUR syndrome. Addition of ethyl alcohol to the irrigating fluid and analysis of alcohol concentration in the expiratory breath constitute a simple but sensitive monitoring technique for early detection of an influx event and its extent. Clinical experience with this method in 50 patients who underwent TURP is reported. The following parameters were determined: heart beats per minute (heart rate), mean arterial pressure, sodium concentration in the serum, duration of resection, and weight of resected tissue. At 10-min intervals, the alcoholic concentration of the expiratory breath of each patient was measured with the AlcoMed 3011 analyzer (Biotest, Dreieich, Germany). Active measurement was possible in 40 patients, and a passive analytic procedure was used in 5 other patients in whom general anaesthesia was induced. In the remaining 5 patients, the monitoring could not be performed because of a medical history of significant alcohol abuse. A suprapubic trokar was used to decrease intravesical pressure in 16 patients. In 8 of 45 patients, alcohol concentration was > 0.2@1000. Three of them developed TUR syndrome. With regard to the frequency of an influx event, there was no significant difference between resections using a trokar and those performed without a trokar. In addition, there was no correlation between this frequency and the duration of resection or the weight of resected tissue. In single cases, influx of considerable fluid volume was found, whereas in 28 patients, duration of resection was far longer than 60 minutes with no signs of an influx event. Mean arterial pressure and heart rate were not altered in 47 patients during the course of the surgical procedure; however, a decrease in these parameters was observed in the 3 patients who developed TUR syndrome. In each of the 8 patients with increased alcohol concentrations, a significant decrease in the serum sodium concentration was observed. There was no change in sodium concentration during the postoperative course in the remaining 42 patients. The data indicate that monitoring of the alcohol load in the expiratory breath is a simple, non-invasive, reliable and cost-efficient way of detecting an influx of fluids during TURP and allows the anaesthetist to take early steps to prevent the development of TUR syndrome.

Inhalational mask induction with nitrous oxide and sevoflurane in young children is an appropriate alternative to intravenous induction and is considered safe and of rapid onset. Disadvantages of this technique are environmental pollution and occupational exposure to the inhalation agents used. Moreover, the potential health hazards are not yet completely clear. The purpose of the present study was to examine the anaesthesiologist's occupational exposure to nitrous oxide and sevoflurane in paediatric anaesthesia and mask induction. Twenty children underwent inhalational induction with nitrous oxide and sevoflurane in the operating theatre (air exchange rate 20.2/h, anaesthetic waste gas scavenger 40 l/min). Anaesthesia was maintained with the same agents. Air samples were taken from the edge of the anaesthesiologist's mouth continuously every 90 seconds, and trace concentrations of nitrous oxide and sevoflurane were analyzed with a direct reading infrared spectrometer (Brüel & Kjaer 1302, Denmark). Measurements taken during anaesthesia showed an increase in the concentrations of the anaesthetics used, but these were low. The highest mean concentrations occurred during induction (3.35 +/- 4.23 ppm for sevoflurane and 37.09 +/- 11.65 ppm for nitrous oxide). The overall peak levels measured were 6.31 +/- 4.23 ppm for sevoflurane and 68.78 +/- 40.79 ppm for nitrous oxide. Though the induction period was short compared to the whole length of anaesthesia, its impact on the overall waste gas exposure was 46.3% for sevoflurane (nitrous oxide 40.6%). Nonetheless, applicable German health law regulations were never infringed. The trace concentrations measured during inhalational mask induction and maintenance of anaesthesia were very low. With regard to modern workplace laws and health care regulations, gaseous induction in paediatric anaesthesia does not threaten the personnel's health.

Carbon monoxide (CO) is a product of incomplete burning of coals and carbon compounds and is a gas without any typical taste, colour or smell. Defective radiators or gas pipes, open fireplaces, fires and explosions are sources of unintended CO production and inhalation. CO bonds with haemoglobin much more readily than oxygen does. CO toxicity causes impaired oxygen delivery and utilisation at cellular level. It affects different sites within the body, but has its most profound impact on the organs with the highest oxygen requirement. CO concentration and the intensity and duration of inhalation determine the extent of intoxication. Following basic life support, assisted or controlled ventilation with 100% oxygen is essential during emergency care. Hyperbaric oxygenation (HBO) is the preferred therapeutic option for releasing CO from its binding to haemoglobin. It has been shown that CO may cause lipid peroxidation and leukocyte-mediated inflammatory changes in the brain, a process that may be inhibited by HBO. Patients with neurological symptoms including loss of consciousness and expectant mothers should undergo HBO treatment, no matter how high their CO levels are. Neonates and in-utero fetuses are more vulnerable due to the natural leftward shift of the dissociation curve of fetal haemoglobin, a lower baseline pO2 and carboxyhaemoglobin levels at equilibration that are 10-15% higher than maternal levels. Physicians need to be aware of the potential occurrence of this life threatening hazard so that appropriate emergency treatment can be administered and fatalities prevented.