Showing papers in "Acta Anaesthesiologica Scandinavica in 1974"

The influence of acid-base changes on central nervous system toxicity of local anaesthetic agents. I. An experimental study in cats.

Abstract: A method is described of stabilising the metabolic and respiratory acid-base status of 90 cats in which 127 local anaesthetic toxicity studies were performed. Nine different local anaesthetic agents were studied. These agents were infused intravenously at a constant rate until the appearance of generalised seizure activity in the EEG from the cortex and amygdala via implanted electrodes. A fall in Paco2, or hydrogen ion activity (aH+) was found to decrease local anaesthetic toxicity, such that a linear correlation was found between the log of the toxic dose and Paco2 and aH+. No correlation was found to the metabolic variable chosen (“non-respiratory” hydrogen activity, aH+NR). The conclusion was that both hydrogen ion activity and Paco2 are of importance in modifying the CNS toxic threshold dose of local anaesthetic agents. ZUSAMMENFASSUNG Es wird eine Methode der Stabilisation des metabolischen und respiratorischen Saure-Basen-Status bei 90 Katzen beschrieben, bei welchen 127 Toxizitatsuntersuchungen mit Lokalanaesthetika durchgefuhrt wurden. Neun verschiedene Lokalanaesthetika, die untersucht wurden, wurden mit gleichbleibender Geschwindigkeit so lange i.v. infundiert, bis im EEG des Cortex und der Mandelkerne-via implantierter Elektroden registriert-generalisierte Krampfpotentiale auftraten. Dabei zeigte sich, das ein Abfallen des Paco2 oder der Wasserstoffionen-Aktivitat (aH+) die Toxizitat der Lokalanaesthetika reduzierte und zwar so, das eine lineare Korrelation zwischen dem Logarithmus der toxischen Dosis und dem PaCo2 bzw. aH+ festgestellt werden konnte. Zu der gewahlten metabolischen Variablen (“nicht-respiratorische” Wasserstoffionen-Aktivitat, aH+NR) konnte keine Korrelation gefunden werden. Die Schlusfolgerung war, das sowohl die Wasserstoffionen-Aktivitat als auch das PaCO2 von Bedeutung fur die Modifizierung der toxischen Schwellendosen von Lokalanaesthetika im ZNS sind.

Miscarriages among operating theatre staff.

Abstract: Altogether 300 married Finnish women working as anaesthesia, scrub, casualty and intensive care unit nurses were interviewed about the fate of their pregnancies since 1965. The scrub nurses had the highest frequency of miscarriages; 21.5% of the pregnancies ended in spontaneous abortion. Intensive care unit nurses had a miscarriage rate of 16.7%, anaesthesia nurses 15.0% and casualty department nurses 8.3% of the pregnancies, respectively. The difference between the rate of the combined number of miscarriages of operating room nurses (anaesthesia and scrub) and that of the others was statistically significant. Scrub nurses seemed to have the earliest miscarriages (mean 9.3 weeks), and intensive care unit nurses also had earlier mean time of miscarriages (10.4 weeks) than anaesthesia nurses (11.1 weeks). Gross abnormalities were not observed in the children, but two cases of foetal death in the third trimester of pregnancy (anaesthesia and intensive care unit nurses) and two cases of mental retardation (scrub and intensive care unit nurses) were registered. The results do not indicate foetal lethality of anaesthetic gases in operating room but rather an increased rate of spontaneous miscarriages due to stress.

Plasma protein metabolism.

Abstract: This survey of plasma protein metabolism will deal almost exclusively with clinical aspects. Disturbed plasma protein metabolism with ensuing alteration of plasma protein concentration is almost as common as an elevated erythrocyte sedimentation rate in clinical medicine. An example is the decrease of serum albumin which occurs almost consistently in acute infections, in coronary thrombosis and following surgery. Furthermore, the metabolism of a specific plasma protein may be altered without any change of its serum concentration. If both the synthetic rate and the degradation rate are doubled, then the serum concentration remains unchanged. This is often the case for the major immunoglobulin class, IgG, in chronic infections. Thus, to obtain information on the effect of a given disease on specific plasma proteins, it is necessary to perform turnover studies.

Pulmonary Microembolism During Intramedullary Orthopaedic Trauma

Abstract: Patients undergoing prosthetic hip surgery by the Charnley method were given 51Cr labelled platelets and 125I labelled fibrinogen the day before the operation. External monitoring of both kinds of radioactivity over the right lung was performed during the surgical procedure. A transient accumulation of 51Cr radioactivity over the lung was noted during broaching of the femoral bone marrow and after impaction of the femoral prosthetic stem. Transient trapping of 125I radioactivity was also recorded during the latter period. Arterial oxygen tension (Pao2) dropped significantly after impaction of the femoral prosthesis. The correlation coefficient was -0.97 between deposition of 125I radioactivity in the lung and the Pao2 reduction occurring after insertion of the femoral prosthesis. These results might indicate a pulmonary microembolism occurring during this stage of the operation, with concomitant pulmonary dysfunction. ZUSAMMENFASSUNG Patienten, die fur prothetische Huftoperationen nach der Methode nach Charnley vorgesehen waren, erhielten am Tag vor dem Eingriff 51Cr-markierte Thrombozyten und 125I-markiertes Fibrinogen. Wahrend des chirurgischen Eingriffes wurden beide Arten der Radioaktivat uber der rechten Lunge extern registriert. Eine vorubergehende Anhaufung der 51Cr-Aktivitat uber der Lunge wurde wahrend des Ausraumens des Knochenmarks aus dem Femur und nach dem Einsetzen der Femurstammprothese beo-bachtet. Wahrend dieser zweiten Phase wurde auch eine vorubergehende Haufung der 125I-Radio-aktivitat registriert. Nach dem Einsetzen der Femurprothese fiel die arterielle Sauerstoffspannung (PaO2) significant ab. Der Korrelationskoeffizient war—0,97 zwischen dem vermehrten Auftreten der 125I-Radioaktivitat in der Lunge und der nach dem Einsetzen der Femurprothese auftretenden PaO2-Reduktion. Diese Resultate konnten als Anzeichen von Mikroembolis-ationen in die Lunge in diesem Operationsstadium interpretiert werden bei gleichzeitiger pulmonaler Dysfunktion.

The influence of acid-base changes on central nervous system toxicity of local anaesthetic agents. II.

Abstract: This study is a detailed analysis of data obtained from 127 experiments on 90 paralysed and ventilated cats regarding the CNS toxicity of nine local anaesthetic agents as evidenced by seizure activity on the EEG. It is shown that an increase in Pco2 or aH+ caused increased CNS toxicity, i.e., smaller i.v. doses were required to elicit seizure activity, and that the underlying metabolic acid-base state can considerably modify this, a metabolic alkalosis decreasing toxicity, and vice-versa. The probable mechanisms of this process involving relationships between pH and the local anaesthetic cation/base ratios in plasma and neural tissue are discussed. It is finally recommended that local anaesthetic convulsions be treated by adequate artificial ventilation, which by lowering the Pco2 in the brain will diminish the local anaesthetic toxicity and thus treat the root cause. ZUSAMMENFASSUNG Diese Untersuchung stellt die Detailanalyse von Ergebnissen dar, die bei 127 Experimental an 90 paralysierten und kunstlich beatmeten Katzen gewonnen wurden in Hinblick auf die ZNS-Toxizitat von neun Lokalanaesthetika, dargestellt mittels Krampfaktivitat im EEC Es zeigte sich, das eine Erhohung des PCo2 oder der Wasserstoffionenaktivitat (aH+) die ZNS-Toxizitat erhohte, d.h. es waren geringere i.v. Dosen erforderlich, urn Krampfpotentiale auszulosen. Es zeigte sich ferner, das der zugrundeliegende metabolische Saure-Basen-Status dies betrachtlich modifizieren kann, wobei metabolische Alkalose die Toxizitat reduziert und umgekehrt. Der wahrscheinliche Mechanismus, an dem wohl Beziehungen zwischen pH und der Lokalanaesthetika-Kationen-Basen-Relationen im Plasma und im Nervengewebe beteiligt sind, wird diskutiert. Schlieslich wird empfohlen, durch Lokalanesthetika bedingte Krampfe mit adaquater kunstlicher Beatmung zu behandeln, damit der Senkung des Pco2 im Gehirn die Toxizitat des Lokalanaesthetikums vermindert und mithin das Ubel an der Wurzel gepackt wird.

Supraclavicular catheterization of the superior vena cava.

Abstract: In seeking to develop a simple and safe technique of central vein catheterization, a supraclavicular route to the superior vena cava was chosen. Advancing from a point above the medial portion of the clavicle, the needle punctures the wall at the confluence of the subclavian and internal jugular veins, and a siliconized catheter is introduced straight into the superior vena cava. The technique is described in detail. The results of 600 catheterizations are reported. Unsuccessful attempts at cannulation were recorded in 6.3%, malposition of the tip of the catheter in 1.7%, pneumothorax in 0.3% and other complications in altogether 3.3% of the cases. Attention is drawn to the potential dangers inherent in cannulation of major central veins. The supraclavicular route described seems to provide a straightforward, reproducible approach to the superior vena cava, and it seems to have a low incidence of technical failures and early and late complications.

Regulation of protein metabolism.

Abstract: Almost all the organic nitrogen of the diet takes the form of amino acids (protein) which have three major fates in the body: a) to provide material for synthesis and maintenance of body proteins, b) to act as precursors of many nonprotein nitrogenous compounds (e. g., nucleic acids), and c) degradation of the excess. The regulation of protein metabolism achieves a balance between these processes which is disturbed by malnutrition and by injury. The regulation of the amount of protein in the body and its compartments is an important feature of protein metabolism. Factors controlling the protein content of the body and of individual tissues during growth and in the adult include amino acid supply, anabolic and catabolic hormones, and intracellular regulatory factors determining cell function at different periods of life. This short review will discuss the regulation of protein metabolism with special emphasis on man. For a general survey, see MUNRO & ALLISON ( 1964) and MUNRO ( 1969, 1970).

The ejector flowmeter and its clinical application.

Abstract: The ejector flowmeter is designed for the quantitative removal of excess anaesthetic gases. By passing compressed air or gas at 2.0-3.5 kg/cm2 pressure through a narrow injector nozzle across the upper end of an ordinary flowmeter tube, a sufficient vacuum is created in the flowmeter to obtain an adjustable removal of gas through the flowmeter; for instance, an anaesthetic gas mixture. The driving gas conveys the anaesthetic gas mixture through a narrow antistatic rubber tube to the nearest ventilation channel or along the floor or ceiling into fresh air through an opening in an outer wall. The ejector flowmeter may be mounted on any anaesthetic machine, being independent of national standard dimensions. It can be attached to all current anaesthetic circuits, including those with an anaesthesia ventilator. The float secures visual control of proper flowmeter function. The evacuation capacity is adjustable up to 15 1/min, and the full capacity is 20-25 1/min. The consumption of driving gas is about 6 1/min. This elimination of gas involves no explosion risk.

A comparison of the local anesthetic properties of bupivacaine and two new long-acting agents, HS 37 and etidocaine, in epidural analgesia.

Abstract: Two new local anesthetics, HS 37 and etidocaine, were evaluated in epidural analgesia and compared with bupivacaine. Initially, a dose-response study was conducted in which concentrations of etidocaine of 0.75%, 1% and 1.5% and concentrations of HS 37 of 0.75% and 1% were employed. On the basis of this study, a double-blind study was performed with 1% etidocaine, 1% HS 37 and 0.5% bupivacaine. This latter study indicated no difference in onset time and duration of maximal segmental spread. Bupivacaine possessed a significantly longer total duration of sensory analgesia. The frequency of satisfactory surgical anesthesia and segmental spread of analgesia were similar for etidocaine and bupivacaine. The frequency of anesthetic supplementation was greater for HS 37 due to a more restricted spread of segmental anesthesia in the sacral area. Etidocaine showed a significantly greater depth of motor paralysis than either bupivacaine or HS 37. Side effects or methemoglobinemia were not observed with any of the agents. Venous blood concentrations of etidocaine following the use of 300 mg revealed a peak plasma level of 1.51 μg/ml and a whole blood concentration of 0.82 μg/ml. The results showed HS 37 and etidocaine to be long-acting local anesthetics comparable to bupivacaine. ZUSAMMENFASSUNG Zwei neue Lokalanaesthetika, HS 37 und Etidocain, wurden bei der Epiduralanalgesie erprobt und mit Bupivacain verglichen. Einleitend wurde eine Dosis-Antwort-Studie durchgefiihrt, wobei Konzentrationen von 0,75%, 1% und 1,5% Etidocain und 0,75% und 1% HS 37 verwendet wurden. Auf Grund diaer Untersuchung wurde ein Doppelblindversuch mit 1% Etidocain, 1% HS 37 und 0,5% Bupivacain unternommen. Diese zeigte keinen Unterschied beziiglich Wirkungseintritt und Dauer der maximalen segmentalen Ausbreitung. Bupivacain wies eine signifikant langere Gesamtdauer der sensorischen Analgesie auf. Die Haufigkeit zufriedenstellender Operations-anaesthesie und die segmentale Ausbreitung der Analgesie war fur Etidocain und Bupivacaiu ahnlich. Bei HS 37 war haufiger eine Zusatzanaesthesie erforderlich, bedingt durch beschranktere Ausbreitung der Segmentalanaathesie im Sakralbereich. Bei Etidocain war die motorische Paralyse signifikant ausgepragter als bei Bupivacain oder HS 37. Nebenwirkungen oder Methaemoglobinaemie wurden mit keinem der Mittel beobachtet. Nach Anwendung von 300 mg Etidocain ergab sich eine maximale veniise Plasmakonzentration von 1,5 1 μg/ml und eine maximale Gesamtblutkonzentration im Venenblut von 0,82 μ/ml. Die Ergebnisse zeigten, das HS 37 und Etidocain lang wirkende Lokalanaesthetika sind, vergleichbar dem Bupivacain.

Reticuloendothelial function under general anaesthesia.

Abstract: The effect of five common anaesthetics on the reticuloendothelial (RE) function was evaluated in 15 patients subjected to minor surgical operations. 125I-labelled micro-aggregated human serum albumin was used as a RE test substance. All anaesthetic techniques (cyclopropane, ether, halothane, neurolept analgesia and epidural) caused a significant impairment of the RE phagocytic function when studied 1 h after the induction. The RE catabolic function was also decreased compared to a control group of volunteers. Possible mechanisms are discussed.

High-frequency positive-pressure ventilation (HFPPV) applied for small lung ventilation and compared with spontaneous respiration and continuous positive airway pressure (CPAP).

Abstract: The respiratory and circulatory conditions in high-frequency positive-pressure ventilation (HFPPV) in the dog and during routine surgery in man have been investigated previously. From this previous experimental and clinical experience, the insufflation-expiratory systems could be modified for small lung ventilation (HFPPV-infant), and the insufflation frequency-insufflation time systems could be combined into one function. This modified HFPPV system works without any separate insufflation catheter. The respiratory and circulatory conditions during ventilation with this modified system were investigated in a series of healthy cats anaesthetized with pentobarbital. The present version of HFPPV utilizes humidified, warmed, compressed air (gas mixture) which is obtained by means of a slightly modified pneumatic part of a commercially available incubator system. By means of intermittent opening of an electronically controlled valve, this gas mixture gives an intermittent positive pressure ventilation at high frequency. It is possible to regulate alveolar ventilation during HFPPV both by means of driving-pressure and expiratory-resistance adjustments, as well as by regulation of the insufflation frequency and insufflation time. In the cat with normal-compliant lungs, HFPPV gives adequate alveolar ventilation at continuous positive and low intratracheal pressures. As it has been shown that methods with continuous positive airway pressure increase arterial oxygenation and prevent airway closure, HFPPV was compared with yet another positive airway technique, continuous positive airway pressure (CPAP). The experimental studies on HFPPV and CPAP in the cat with normal-compliant lungs revealed that HFPPV - in contrast to CPAP - gives adequate alveolar ventilation without circulatory interference. The electronically coupled function of insufflation frequency and time (“respirator setting”) in HFPPV was also tested, and it was shown that the arterial Po2 is mainly influenced by the respirator driving pressure but that the arterial Pco2 and pH are additionally influenced by the respirator setting.

Computerized measurement of cardiac output by thermodilution: methodological aspects.

Abstract: A computerized thermodilution method for cardiac output measurement is described. A solution of 5% glucose at room temperature was used as an indicator. Frequent measurements can be made and instantaneous readings of the cardiac output values obtained. The method had a coefficient of variation of 4.4% in clinical situations and 3.4% in experimental situations. The technique provides possibilities for simultaneous recordings of pulmonary arterial and central venous pressures. Possible errors affecting the validity of the method are discussed. The method described has proven to be valuable within both experimental and clinical work. ZUSAMMENFASSUNG Es wird eine computerisierte Thermodilutions-Methode zur Bestimmung des Herzzeitvolumens beschricben. Als Indikator wird 5%-ige Dextrose bei Zimmer-temperatur verwendet. Es konnen haufige Messungen durchgefuhrt werden bei sofortiger Ablesbarkeit der HZV-Werte. Das Instrument hat eine Mesfehlerbreite von 4,4%. Diese Technik ermoglicht Simultanauf-zeichnungen des Pulmonalarterien- und des zentral-venosen Druckes. Mogliche Fehler, die den Wert der Methode beeintrachtigen konnten, werden dis-kutiert. Die beschriebene Methode hat sich sowohl in der experimentellen als auch in der klinischen Arbeit bewahrt.

Acidosis and neuromuscular blockade.

Abstract: The effect of different types of acidosis on sensitivity to neuromuscular blocking agents was studied in vivo on the tibialis muscle of cats and in vitro in the phrenic nerve diaphragm preparation of the rat. In vivo metabolic acidification was caused by diffusion of weak organic acids, which penetrate easily into the cell and imitate closely the state of metabolic acidosis in man. Respiratory acidosis was caused by inhalation of 10% carbon dioxide in oxygen. In the in vitro experiments, acidification was caused by titration with the same acids as well as hydrochloric acid. pH was lowered to levels just above 7.0. Blank in vivo studies showed that the metabolic acidosis by itself causes no significant depression of indirect muscle contraction, while respiratory acidosis causes only a slight depression. A minor depression was seen in the blank in vitro metabolic acidosis studies. Both succinylcholine and decamethonium blocks are strongly antagonised in vivo and in vitro by metabolic and respiratory acidosis. Pancuronium bromide block was potentiated by metabolic and respiratory acidosis both in the in vivo and in vitro experiments. It is most likely that changes in transmembrane potential are the cause for the changes in sensitivity seen in these experiments. ZUSAMMENFASSUNG Der Einfluss verschiedener Arten von Azidose auf die Empfindlichkeit fur muskelerschlaffende Mittel wurde mit Hilfe von in vivo Experimenten auf den Tibialis-Muskel der Katze und in vitro Experimenten auf das Phrenicus-diaphragma-Praparat der Ratte untersucht. Die metabole Azidose wurde in vivo durch schwache organische Saure hervorgerufen, welche schnell in die Zelle hineintreten und der metabolen Azidose beim Mensch am nachsten stehen. Respiratorische Azidose wurde durch Inhalation von 10% Kohlensaure im Sauerstoff hervorgerufen. In den in vitro Experimenten wurde die Azidose durch Titration der Spulflussigkeit mit den selben Sauren und mit Salzsaure hervorgerufen. Das pH wurde bis gerade oberhalb 7.0 herabgedruckt. Blanke in vivo Experimente zeigten, dass die metabole Azidose selbst keine signifikante Erniedrigung der indirekten Muskelkontraktion ergibt und respiratorische Azidose nur eine leichte. Auch in den in vitro Experimenten wurde eine leichte Depression durch die metabole Azidose festgestellt. Die Muskelerlahmung durch Succinylcholine und Decamethonium wurde durch metabole und respiratorische Azidose in vitro und in vivo starkstens antagonisiert. Muskelerschlaffung durch Pancuronium wurde aber durch metabole und respiratorische Azidose in gleiche Weise in den in vitro und in vivo Experimenten potenziert. Die Anderungen des Ruhepotentials der Zellmembrane werden als verantwortlich fur die Empfindlichkeitsveranderungen angesehen.

The Quest for a Short‐Acting Nondepolarizing Neuromuscular Blocking Agent

Abstract: Current developments in the pharmacology of neuromuscular blocking agents indicate that within the next several years, nondepolarizing drugs of short and intermediate duration of action, devoid of significant side effects, may become a reality. The important factors which may permit their development are reviewed.

Trauma: Hormonal Factors with Special Reference to Diabetes Mellitus

Abstract: Three aspects of the role of hormones in stress will be reviewed: 1) changes in hormone secretion during stress, 2) metabolic alterations as a consequence of these changes in hormone production, and 3) the significance of hormones as permissive factors in stress reactions. It is emphasized that body tissues in general - except for the central nervous system - can make use of free fatty acids as a source of energy. In order to provide the central nervous system with its requirement for glucose, the glucose uptake in other tissues is restrained by two hormonally controlled mechanisms: 1) depression of insulin secretion and 2) increase in the concentration of free fatty acids in plasma (which by direct means depresses glucose uptake). Thus, these hormonal interactions provide large amounts of metabolic fuel and distribute them in an effective manner, so that the body can meet stress. In diabetics, an increased secretion of stress hormones in connection with trauma is observed. The metabolic and therapeutic implications of this finding are discussed.

Pulmonary Venoconstriction by Induced Platelet Aggregation

Abstract: Fourteen mongrel dogs were subjected to intravenous infusions of thrombin or protamine chloride in order to induce in vivo platelet aggregation. As a result, the platelet count of blood decreased acutely to 20–30% of the preinfusion value. Together with the fall in the platelet count, there was observed in the thrombin experiments a rise in the pulmonary artery pressure (PA) from 192 (s.d.) to 41 13 mmHg. Simultaneously, the pressure in a small intrapulmonary vein (SPV) increased from 10 3 to 22 10 mmHg. Similar results were obtained in the protamine experiments where the PA increased from 20 5 to 37 8 mmHg and the SPV from 10 3 to 23 6 mmHg. The airways were also affected, as evidenced by a rise in tracheal insufflation pressure by 36 32 and 71 53%, respectively. The rise in tracheal pressure was not the cause of the rise in SPV since apnea did not prevent it. It is suggested that vasoconstriction rather than intravascular obstruction caused the rise in SPV. ZUSAMMENFASSUNG Um eine “in-vivo”-Thrombozytenaggregation einzuleiten, erhielten 14 Bastardhunde intravenose Infusionen von entweder Thrombin oder Protaminchlorid. Als Resultat davon fiel die Thrombozytenzahl akut auf 20–30% des Vor-Infusions-Wertes. Gleichzeitig mit dem Thrombozytensturz wurde bei den Thrombinexperimenten ein Anstieg des Pulmonalarteriendruckes (PPA) von 19±2 (x± s.d.) auf 41 ± 13 mmHg beobachtet. Gleichzeitig stieg der Druck in einer kleinen intrapulmonalen Vene (PSPV) von 10 ± 3 auf 22 ± 10 mmHg an. Ahnliche Resultate ergaben sich bei den Protamin-Versuchen, bei denen der PPA von 20 ± 5 auf 37±8 mmHg und der PSPV von 10±3 auf 23±6 mmHg anstiegen. Als Zeichen einer gleichzeitigen Beeintrachtigung der Atemwege ergab sich eine Erhohung des trachealen Insufflationsdruckes um 36±32 bzw. 71±53 %. Die Erhohung des Intratrachealdruckes war jedoch nicht die Ursache des Anstieges des PSPV denn dieser zeigte sich auch bei Apnoe. Es wird angenommen, das der erhohte PSPV eher durch Vasokonstriktion als durch eine intravaskulare Obstruktion zustande kommt.

Psychomotor skills related to driving after intramuscular lidocaine.

Abstract: Psychomotor skills related to driving and the ability to discriminate the fusion of flickering light were measured double-blind in 30 healthy volunteer students 25, 90 and 180 min after an intramuscular injection of either lidocaine (200 mg), lidocaine (500 mg) with adrenaline, or a saline placebo. The tests used were an attention test, two coordination tests and a choice reaction test. After plain lidocaine, the cumulative reaction times were significantly (P<0.05) longer at 25 min than after saline or lidocaine with adrenaline. Lidocaine with adrenaline did not impair psychomotor performance or flicker fusion discrimination. Thus the results suggest that patients treated with high dosages of plain lidocaine should not drive or operate machinery for 1-1 1/2 h after the injection. ZUSAMMENFASSUNG Bei 30 gesunden Freiwilligen (Studenten) wurden 25, 90 und 180 Minuten nach i.m. Injektion von entweder Lidocain (200 mg), Lidocain (500 mg) mit Adrenalin, oder Kochsalzlosung im Doppelblindversuch psychomotorische Geschicklichkeiten, wie sie fur das Autofahren benotigt werden, sowie die Fahigkeit, blinkendes Licht als solches zu erkennen, getestet. Es handelte sich dabei urn einen Aufmerk-samkeitstest, zwei Koordinationsteste und einen Auswahl-Reaktionstest. 25 Minuten nach einfachem Lidocain waren die kumulativen Reaktionszeiten signifikant (P < 0,05) langer als nach Kochsalz oder Lidocain-Adrenalin. Lidocain-Adrenalin beeintrach-tigte weder die psychomotorischen Leistungen noch die Erkennung von Blinklicht. Unsere Resultate weisen darauf hin, das Patienten, die mit groseren Dosen von Lidocain ohne Adrenalinzusatz behandelt worden waren, fur eineinhalb Stunden nach der Injektion weder ein Auto lenken noch eine Maschine betreiben sollten.

Malignant hyperthermia in a family: a clinical and serological investigation of 139 members.

Abstract: In a family of 147 members, two have died from malignant hyperthermia induced by general anaesthesia, and six from other causes. The remaining 139 family members have all been examined clinically and serologically. Forty per cent of the family members had musculoskeletal disorders and 30% had elevated values of creatine phosphokinase in serum. The mode of inheritance is shown not to be autosomal dominant. Doubt is expressed concerning the value of the determination of creatinine phosphokinase (CPK) in serum. It is concluded that it is uncertain whether such determination can predict the risk of the individual patient for developing malignant hyperthermia. Emphasis is laid upon prophylaxis by issuing cards to members of families at risk, by questioning all patients preoperatively about anaesthesiological complications among family members, and by temperature monitoring. It is suggested that any case of malignant hyperthermia give rise to investigation of the family.

Hepatic blood flow and cardiac output during halothane anesthesia: an animal study.

Abstract: Correlated values of cardiac output and liver blood flow were measured on eight dogs. Measurements were carried out under basis anesthesia with O2-N2O-barbiturate-gallamonium with controlled ventilation as well as during the addition of 0.5% and 1.0% halothane to the inspiratory air. During the latter type anesthesia, a parallel fall in the cardiac output and the liver blood flow was demonstrated. With 0.5% halothane, the fall was on the average 30% and 25% of the initial values respectively, and with 1.0% halothane it was 49% and 45% of the initial values. The individual changes were extremely dependent upon simultaneous changes in Paco2. The fall in cardiac output and liver blood flow was least when the Paco2 increased at the same time, and greatest when the Paco2 fell simultaneously. No changes were demonstrated in the total peripheral resistance and the resistance in the splanchnic region. It is concluded that changes in the cardiac output and hepatic blood flow brought about by the Paco2 are parallel, and this appears to be undiminished during anesthesia with O2-N2O-halothane in the concentrations used here. ZUSAMMENFASSUNG An 8 Hunden wurden die Korrelationswerte des Herzminutenvolumens (HMV) und der Leberdurchblutung gemessen. Diese Untersuchungen wurden in O2-N2O-Barbiturat-Gallamin-Basisnarkose mit kontrollierter Beatmung durchgefuhrt und wahrend eines Zusatzes von 0,5 bzw. 1,0% Halothan im Einatemgemisch. Unter Halothan konnte ein parallel verlaufender Abfall des HMV und der Leberdurchblutung nachgewiesen werden. Bei 0,5% Halothan betrug dieser im Durchschnitt 30 bzw. 25% der Ausgangswerte, bei 1% Halothan 49 bzw. 45%. Individuelle Schwankungen waren im hochsten Mase von gleichzeitigen PaCo2-Veranderungen abhangig. Der Abfall des HMV und der Leberdurchblutung war am geringsten, wenn gleichzeitig das PaCo2 anstieg und am starksten, wenn das PaCo2 gleichzeitig absank. Im peripheren Gesamtwiderstand sowie im Gefas-widerstand des Splanchnikus-Bereiches konnten keine Veranderungen nachgewiesen werden. Es wird daraus der Schlu|sZ gezogen, das die PaCo2-bedingten Veranderungen des HMV und der Leberdurchblutung miteinander verbunden sind und das sich dies auch wahrend der Narkose mit O2-N2O-Halothan in den hier verwendeten Konzentrationen nicht andert.

Cerebral Metabolic Changes in Arterial Hypocapnia of Short Duration

Abstract: In order to study the energy metabolism of the brain in pronounced hypocapnia, lightly anaesthetized rats were hyperventilated to arterial CO2 tensions of minimally 10 mmHg during 2, 5 and 45 min, respectively. There were marked increases in the tissue concentrations of lactate (and pyruvate) already at 2 min, but no changes in phosphocreatine, ATP, ADP or AMP at 2 or 5 min. It is concluded that the lactic acidosis observed in the tissue during hyperventilation is unrelated to a derangement of the energy state of the tissue. Measurement of other glycolytic substrates seems to indicate an activation of phosphofructokinase, but the possibility that the accumulation of lactate (and pyruvate) at the present degree of hypocapnia is secondary to an activation of other enzymatic steps cannot be ruled out. ZUSAMMENFASSUNG Um den Energiestoffwechsel des Gehirns unter ausgepragter Hypokapnie zu studieren, wurden oberflachlich narkotisierte Ratten auf arterielle CO2-Spannungen von minimal 10 mm Hg wahrend 2, 5 bzw. 45 Minuten hyperventiliert. Schon nach zwei Minuten zeigten sich deutliche Anstiege der Gewebekonzentrationen von Laktat (und Pyruvat), aber keine Veranderungen des Phosphor-Kreatins, der ATP, ADP oder AMP nach 2 bzw. 5 Minuten. Es wird daraus geschlossen, das die in den Geweben wahrend der Hyperventilation beobachtete Laktatazidose in keiner Beziehung zu einer Stoning des Energiezustandes der Gewebe steht. Messungen anderer glykolytischer Substrate scheinen auf eine Aktivation der Phosphofruktokinase hinzuweisen, aber die Moglichkeit, das die Anhaufung von Laktat (und Pyruvat) bei den gegenstandlichen Werten der Hypokapnie die Folge einer Aktivation anderer enzymatischer Schritte sein konnte, ist nicht auszuschliesen.

Nitrous oxide-oxygen-relaxant anaesthesia in alcoholics: a retrospective study.

Abstract: In order to study the action of anaesthetics in chronic alcoholics, the records of male alcoholics (annual consumption over 151 of absolute alcohol) operated upon for pancreatitis were analyzed retrospectively. The records of 46 males and 46 females matched for age, weight and duration of anaesthesia served as controls. Nitrous oxide-oxygen-relaxant anaesthesia supplemented after thiopental induction with analgesics and often additionally with droperidol, halothane and/or thiopental was used in all patients. In alcoholics, higher dosages of anaesthetics were used in induction and supplementation than in control patients. Nevertheless, signs of inadequate anaesthesia were seen more often in alcoholics, about 20% of whom, mostly “heavy drinkers”, complained of awareness or bad dreams. The demand for anaesthetics was also increased in alcoholics in a run-down condition or in those with cirrhosis of the liver. The incidence of pre- and postoperative complications seemed to be similar in all groups. The importance of a detailed prospective study is stressed in elucidating the factors which contribute to the cross tolerance between alcohol and different anaesthetics.

Energy requirements in injury and sepsis

Abstract: Our knowledge of the sequence of metabolic alterations in the patient suffering major trauma or infection has made considerable progress during the past 50 years. However, much more attention has been given to the problems of shock and early resuscitation than to the more slowly unfolding changes of convalescence. The injured or septic patient may have his circulation restored, but he then faces a period of acute tissue catabolism and weight loss followed by a longer period of tissue restoration, before convalescence is complete. Some of the confusion in the literature regarding the metabolic changes in a surgical patient arise from failure to differentiate between the early changes of shock and resuscitation versus the later changes of catabolism and anabolism. I will restrict my comments to the consideration of changes during acute catabolism, since our present ability to manage the patient in shock has greater success than our ability to prevent or minimize the secondary complications following resuscitation.

Etidocaine (Duranest®): A Clinical and Laboratory Evaluation

Abstract: The results of a clinical and laboratory evaluation of the new local anesthetic etidocaine for conduction anesthesia in a series exceeding 2200 cases are reported in detail. It has a high frequency, rapid onset of action, slow regression as well as a prolonged duration of sensory and motor blockade exceeding that of bupivacaine. The peak venous blood plasma concentration curves following peridural anesthesia are lower than those of an equipotent concentration of bupivacaine. Reference is also made to pharmacokinetic studies which suggest that this agent has a lower systemic toxicity or therapeutic index than other local anesthetic agents. Appropriate concentrations for various conduction anesthesia procedures vary from 0.5 to 1.5%. It is indicated that the low systemic toxicity and prolonged duration of action of etidocaine is related to its high plasma protein binding capacity and enhanced lipid solubility. The structural formula and chemical properties of this stable amide are quite similar to those of lidocaine. ZUSAMMENFASSUNG Es wird uber die Ergebnisse einer klinischen und Laboratoriumsauswertung des neuen Lokalanaesthetikums Etidocain zur Leitungsanaesthesie in einer Serie von uber 2200 Fallen im Detail berichtet. Seine Wirkungsfrequenz ist hoch, der Wirkungseintritt rasch, der Wirkungsverlust langsam. Die Dauer der sensorischen und motorischen Blockade ubertrifft die des Bupivacains. Die Spitzenwerte der venosen Blutplasmakonzentrationen nach Periduralanaesthesien sind niedriger als nach wirkungsgleichen Mengen von Bupivacain. Es wird auf pharmakokinetische Untersuchungen verwiesen, die ergaben, das dieses Agens eine niedrigere systemische Toxizitat, bzw. therapeutischen Index hat als andere Lokalanaesthetika. Gecignete Konzentrationen fur verschiedene Methoden der Leitungsanaesthesie liegen zwischen 0,5 und 1,5%. Es wird betont, das die geringe systemische Toxizitat und langere Wirksamkeit von Etidocain auf seiner hohen Plasmaprotein-Bindungskapazitat und vermehrten Lipoidloslichkeit beruht. Die Strukturformel und die chemischen Eigenschaften dieses stabilen Amids sind ganz ahnlich denen des Lidocains.

General metabolic response to trauma including pain influence.

Abstract: A review is presented of the posttraumatic response from the endocrine and metabolic aspects. The importance of afferent nerve impulses and other factors of importance in the activation of the response are discussed.

Diazepam Compared to Thiopentone as Induction Agent for Caesarean Sections

Abstract: Eighty-nine unselected women to undergo caesarean section were induced intravenously with either 20 mg diazepam (45 patients) or 200 mg thiopentone (44 patients). To facilitate intubation suxamethonium was injected 1 min after the induction agent and was also given by continuous infusion throughout the procedure. The patients were ventilated with N2O/O2 (3:2). Immediately after delivery all the mothers received 50 mg pethidine and 100 mg thiopentone intravenously. Unpleasant recollections and dreams occurred in 23% of the thiopentone series and in only 2% of the diazepam series. No significant difference in the condition of the neonates in the two series could be detected. One woman received 120 mg diazepam intravenously for the control of epilepsy shortly before delivery without apparent ill effect on the neonate. The incidence of moderate to severe suxamethonium pains was 33% in the diazepam series and only 14% in the thiopentone series. In elective caesarean sections with normal preinduction values of serum creatine phosphokinase, the postoperative rise in the serum activity of this enzyme was significantly higher in the diazepam mothers compared to those who had received thiopentone. Thiopentone therefore in some way protects against suxamethonium-induced muscle pains as well as liberation of creatine phosphokinase from the muscles. It is suggested that this is due to the deep level of anaesthesia occurring 1 min after 200 mg thiopentone in contrast to the semiconscious state occurring after 20 mg diazepam. ZUSAMMENFASSUNG 89 nicht ausgewahlte Frauen, bei denen eine Sectio caesarea vorgesehen war, wurden i.v. entweder mit 20 mg Diazepam (45 Patientinnen) oder mit 200 mg Thiopental (44 Patientinnen) eingelehet. Suxamethonium wurde eine Minute nach der Anaesthesieeinleitung zur Erleichterung der Intubation und anschlieRend als Dauertropfinfusion wahrend der Operation gegeben. Die Patientinnen wurden mit N2O/O2 (3:2) beatmet. Unmittelbar nach der Geburt erhielten alle Mutter 50 mg Pethidin und 100 mg Thiopental i.v. Unangenehme Erinnerungen und Traume traten bei 23% der Thiopentalserie und nur bei 2% der Diazepam-Patientinnen auf. Bezuglich des Zustandes der Neugeborenen konnte kein Unterschied zwischen den beiden Gruppen festgestellt werden. Eine Frau bekam kun vor der Geburt 120 mg Diazepam i.v. als Epilepsieprophylaxe, ohne daR sich ein offensichtlicher nachteiliger Effekt fur das Kind ergab. In der Diazepamserie sahen wir bei 33%, in der Thiopentalserie jedoch nur bei 14% der Patientinnen mittelstarke bis schwere. Suxamethoniumschmerzen. Bei den elektiven Kaiserschnittpatientinnen mit normalen Vonverten der Serum-CPK ergab sich unter den Diazepam-Muttern ein signifikant hoherer postoperativer Anstieg der Serumaktivitiit dieses Enzyms verglichen mit denen, die Thiopental erhalten hatten. Thiopental scheint also bis zu einem gewissen Grad Schutz gegen Suxamethonium-bedingte Muskelschmerzen ebenso wie gegen die CPK-Freisetzung aus der Muskulatur zu bieten. Wir glauben, das dies der tieferen Narkose eine Minute nach 200 mg Thiopental zuzuschreiben ist, gegenuber dem Zustand einer HalbbewuRtlosigkeit nach 20 mg Diazepam.

Therapy with fat emulsion.

Abstract: Fat emulsions for paranteral nutrition are indicated to maintain a physiological nutrition during impaired function of the gastrointestinal tract. Modern fat emulsions seem to metabolize in the same way as chylomicrons. It is usually possible to infuse a dose of fat up to 3–4 g/kg b.w./24 h. Fat emulsions as such have no osmolal effects and are therefore also indicated during treatment of hyperosmolal fluid balance disturbances.

Normal carbohydrate metabolism and carbohydrate metabolism in trauma.

Abstract: The great lability of man's glucose reserves as shown by the decreases in liver glycogen both during short starvation, decreased intake of carbohydrate or as an effect of trauma shows the importance of carbohydrate administration both in the normal man and in the treatment of trauma. Even if a relative intolerance to glucose is seen in the post-traumatic phase, it seems reasonable to use glucose possibly together with insulin as the basic calorie supply. The most important reason for this is that during hypoxia, which can readily occur, the only useful fuel is glucose transported via the blood or stored in the tissues as glycogen.

Treatment of Post‐Operative Pulmonary Atelectasis by Active Inflation of the Atelectatic Lobe(s) Through an Endobronchial Tube: Case Reports

Abstract: Two cases of post-operative pulmonary atelectasis were treated by a procedure not previously described in the literature Following bronchoscopic suction, the main bronchus on the affected side was inflated with a mixture of air and oxygen through an endobronchial tube passed under direct vision over a bronchoscope This resulted in immediate re-expansion of the atelectatic lung ZUSAMMENFASSUNG Zwei Falle von postoperativen Lungenatelektasen wurden mit einer Methode behandelt, die bischer in der Literatur nicht beschrieben ist Nach bronchoskopischer Absaugung wurde der Hauptbronchus der betroffenen Seite mit einer Mischung aus Luft und Sauerstoff uber einen Endobronchialtubus aufgeblaht Dieser wurde uber ein Bronchoskop gezogen und unter direkter Sicht eingefuhrt Die geschilderte Masnahme fuhrte zu einer sofortigen Re-Expansion der intubierten Lunge

The treatment of hypercatabolic acute renal failure by adequate nutrition and haemodialysis.

Abstract: Despite all therapeutic advances, the management of acute renal failure in surgical cases still involves many unsolved problems. In our dialysis unit, 100 surgical patients aged from 9 weeks to 82 years, had to be dialysed for established acute renal failure. Tubular necrosis developed within posttraumatic crush syndromes, haemorrhagic shock or following extensive abdominal, cardiovascular or urological surgery, in many cases complicated by septicaemia. Hypercatabolism with a daily plasma urea increment exceeding 60 mg/100 ml played a dominating role in the course of most of the severely ill patients. Early initiation of dialysis, performed daily if necessary, in combination with high caloric parenteral nutrition, mainly reduced uraemic complications. Despite all progress in the management of acute renal failure, mortality still was distressingly high accounting for 78%, in the majority of cases due to secondary complications arising in the course of the illness. ZUSAMMENFASSUNG Trotz aller therapeutischen Fortschritte ist bei der Behandlung des akuten Nierenversagens chirurgischcr Patienten noch eine Vielzahl von Problemen ungelost. Bislang wurden in unserem Dialysezentrum 100 Patienten im Alter von 9 Wochen bis 82 Jahren behandelt, bei denen sich nach schweren Unfallen, ausgedehnten abdominal- sowie herz- und gefaschirurgischen Eingriffen ein akutes Nierenversagen etabliert hatte. Bei der Mehrzahl der Falle bestand ein “hyperkataboles” Nierenversagen mit einem taglichen Harnstoffanstieg von uber 60 mg%. Durch fruhzeitige, bei Bedarf taglich durchgefuhrte Dialyse, in Verbindung mit hochkalori-scher parenteraler Ernahrung konnten uramische Komplikationen weitgehend vermieden werden. Trotz Einsatz aller zur Verfugung stehenden Behandlungs-moglichkeiten war die Mortalitat dieser Falle mit 78% noch bedruckend hoch.

Preliminary clinical evaluation of etidocaine (Duranest): a new long-acting local anesthetic agent.

Abstract: Etidocaine represents a new anilide-type local anesthetic structurally related to lidocaine. In pre-clinical tests, the anesthetic potency was four times that of lidocaine, and the duration of action in equipotent concentrations was two times longer than lidocaine. Thirty-one patients received intercostal nerve block anesthesia with 30–60 ml of etidocaine in concentrations of 0.25% and 0.5% with 1:200,000 epinephrine added. Sensory anesthesia was complete in 6–9 min and lasted approximately 790 min. Fifty patients received lumbar epidural anesthesia with 20 ml of etidocaine in progressive concentrations from 0.25% to 1.5% with 1:200,000 epinephrine added. In all concentrations, anesthesia was complete in less than 20 min and lasted from 384 to 655 min. Interestingly, the 1.5% concentration provided a shorter duration than did the 1% dose. Up to and at the 300 mg dose of etidocaine with 1:200,000 epinephrine, no signs of local or systemic toxicity, cardiovascular disturbance, or organ function abnormalities were observed. ZUSAMMENFASSUNG Etidocaine ist ein neues Lokalanaesthetikum vom Typus der Anilide, strukturell dem Lidocain verwandt. Bei vorklinischen Tests zeigte es eine vierfache Wirkungsstarke gegenuber dem Lidocain und in wirkungsgleichen Konzentrationen war seine Wirkungsdauer doppelt so lang als die des Lidocain. Bei 31 Patienten wurden Intercostalblockaden mit 30–60 ml Etidocaine in Konzentrationen von 0,25 und 0,5% unter Zusatz von 1:200.000 Adrenalin durchgefuhrt. Innerhalb von 6–9 Minuten trat komplette sensorische Anaesthesie auf und dauerte ungefahr 790 Minuten. 50 Patienten erhielten eine lumbale Epiduralanaesthesie mit 20 ml Etidocaine in steigenden Konzentrationen von 0,25%–1,5% unter Zusatz von Adrenalin 1:200.000. Bei alien Konzentrationen war die Anaesthesie in weniger als 20 Minuten komplett und dauerte zwischen 384 und 655 Minuten. Interessanterweise zeigte die l,5%ige Losung eine kurzere Wirkungsdauer als die 1%ige. Bis zu einschlieslich 300 mg Etidocaine mit Adrenalin 1:200.000 wurden keine Zeichen von lokaler oder systemischer Toxizitat, kardiovaskularen Storungen oder abnorme Organfunktionen beobachtet.