bluuebunny/crossref_metadata_2025 huggingface dataset:
Buprenorphine as premedication and as analgesic during and after light isoflurane‐N2O‐O2 anaesthesia. A comparison with oxycodone plus fentanyl
Authors: Korttila K. , Hovorka J.
Published: January 2009

Sixty patients undergoing gynaecological laparotomies under isoflurane anaesthesia received 0.4 mg of buprenorphine sublingually or 0.12 mg/kg of oxycodone intramuscularly in random order for preanaesthetic medication. Patients premedicated with buprenorphine were given buprenorphine before, during and after anaesthesia and patients premedicated with oxycodone received fentanyl before and during anaesthesia and oxycodone after anaesthesia. Buprenorphine premedication produced less drowsiness and sedation and alleviated patients' apprehension significantly (P<0.05) less than oxycodone. Systolic and diastolic blood pressure and heart rate were significantly (P<0.05 to P<0.01) higher after intubation in the buprenorphine group when compared with the oxycodone plus fentanyl group. After anaesthesia, spontaneous respiration started rapidly; the return of consciousness and immediate recovery occurred at the same rate in both groups. In the recovery room moderate to severe pain was more common (P<0.05) in the oxycodone plus fentanyl group than in the buprenorphine group. The respiratory rate in the recovery room was lower among patients given buprenorphine, and two patients given buprenorphine developed severe respiratory depression. In the ward (2 to 24 h after operation) sublingual buprenorphine provided pain relief as good as intramuscularly administered oxycodone. No differences were noted in the incidence or severity of emetic symptoms between the groups. It is concluded that buprenorphine can provide good postoperative pain relief for gynaecological laparotomies performed under light isoflurane anaesthesia, but patients need to be monitored carefully after operation because of the possibility of respiratory depression.
Decrease in serum potassium concentration during epidural anaesthesia
Authors: Hahn R. G.
Published: January 2009

A mean decrease in the arterial serum potassium concentration (S‐K) of 0.40 mmol/1 (range 0–1.0) was found in 45 elderly men who were studied before and after induction of epidural anaesthesia (using mepivacaine 2% with adrenaline). The decrease was similar in patients who received acetated Ringer solution or dextran 40 in normal saline as intravenous fluid supplementation. No difference in S‐K change was found between patients with a normal (< 115 μmol/l) or elevated serum creatinine concentration. The decrease in S‐K prevailed at the end of surgery except in patients with an elevated serum creatinine. Corrections of S‐K for changes in arterial blood pH and rectal temperature during induction of anaesthesia did not explain the decrease in S‐K. Correlations of clinical parameters such as the extension of anaesthesia, amount of intravenous fluid given and blood pressure changes gave conflicting results. A smaller decrease or no change in S‐K was usually seen in arterial (n = 7) and venous (n = 7) samples when no intravenous fluid was given, as well as in venous samples when acetated Ringer solution was given (n = 6).
Histamine release from basophil leukocytes in asthma patients after in vitro provocation with various neuromuscular blocking drugs and intravenous anaesthetic agents
Authors: Guldager H. , Søndergaard I.
Published: January 2009

Basophil histamine release is a relatively new investigation technique, which can be used in the diagnosis of anaphylactoid reactions. Our aim in this investigation was to determine reference values for asthma patients and normal subjects. Blood from eight asthmatic patients and eight normal subjects was tested for histamine release after in vitro provocation with various neuromuscular blocking drugs and intravenous anaesthetic agents. There was significantly higher histamine release for asthmatic patients than for normal subjects, P<0.001 (analysis of variance). This had no effect on the calculated reference value (mean ± 2 s.d.), which was found to be 0–30%.
Sympatho‐adrenal and pituitary hormone responses during and immediately after thoracic surgery ‐ modulation by four different pain treatments
Authors: Scheinin B. , Scheinin M. , Asantila R. , Lindberg R. , Viinamäki O.
Published: January 2009

Four different pain treatments (single intercostal block with bupivacaine, repeated intercostal block, epidural morphine and epidural bupivacaine infusions) were compared in 39 patients subjected to lung surgery under general anaesthesia. The patients' own estimate of the postoperative pain was not significantly different between the groups, but the epidurally treated patients required fewer doses of supplementary analgesic than those given just a single dose of intercostal bupivacaine. Bupivacaine levels in blood were below the toxic range in all groups. The concentration of antidiuretic hormone in blood was increased early during the operation, and had only partly returned to normal on the first postoperative morning. Growth hormone in plasma was increased only at the end of the operation. Catecholamine levels in blood increased gradually, reaching their peak postoperatively. There were only slight differences between the groups in these posterior and anterior pituitary and sympatho‐adrenal responses to surgical stress. Thus, neither repeated intercostal blockade nor epidural administration of morphine or bupivacaine could prevent the endocrine responses to thoracic surgery, in spite of significant, albeit incomplete, pain relief. This was probably caused in part by residual pain, and also by poor access of the extradural medications to the autonomic afferent pathways mediating nociceptive signals from thoracic organs and tissues.
No increased incidence of postoperative sore throat after administration of suxamethonium in endotracheal anaesthesia
Authors: Jørgensen L. N. , Weber M. , Pedersen A. , Münster M.
Published: January 2009

Sixty patients were divided into two groups (A and B) of 30 patients each to investigate the effect of using suxamethonium in endotracheal anaesthesia on the incidence of postoperative sore throat. The patients were anaesthetized with thiopentone, fentanyl, droperidol, N2O and pancuronium. Before endotracheal intubation with a Mallinckrodt® lo‐pro™‐tube, patients in Group A were given pancuronium, whereas patients in Group B were given suxamethonium. There was no difference in the incidence or severity of sore throat 20–30 h postoperatively between the two groups (P = 0.5). The type 2 error (β) was low (the risk of overlooking a “true” difference in incidence of 0.20 was calculated to be 0.04). These results contradict those of a recent study, which demonstrated an increased incidence of postoperative sore throat following the use of suxamethonium in mask anaesthesia.
Intraspinal analgesia: an historical overview
Authors: Benedetti Costantino
Published: January 2009

The application of opioids in the proximity of the spinal cord is a recent addition to the forms of treatment available for pain relief. During the last 20 years we have learned more about the intimate mechanisms of the action of opiates then we had in the preceding 5 millennia. Opium, in fact, has been used for medical purposes from prehistoric times. On the basis of the newly acquired knowledge, we are now applying opioids in more effective ways and providing more patients with long overdue relief of their pain.
Spinal opiates: a review of their effect on spinal function with emphasis on pain processing
Authors: Yaksh Tony L.
Published: January 2009

Several opiate receptor systems have been identified in the spinal cord. They produce a powerful analgesia when opioid agonists are administered intrathecally in the intact, unanesthetized animal. These effects appear mediated by an action on opioid receptors which are located presynaptically, in the terminals of primary afferents, and postsynaptically on certain dorsal horn neurons. Based on structure‐activity relationships in different tests, quantitative studies of naloxone antagonism and selective cross tolerance, it appears that, in the spinal cord, there are three distinguishable populations of opioid receptors: mu, delta and kappa. Aside from the effects on nociception, these receptors are also associated with a variety of spinal mechanisms related to other aspects of sensory, autonomic and motor functions. Though in some cases these represent important side‐effects (e.g. inhibition of the micturition reflex), in others, the subtle effects may have important therapeutic benefits (e.g. relieving spasticity in spinal injured patients).
Intraventricular morphine for intractable cancer pain: rationale, methods, clinical results
Authors: Lobato Ramiro D. , Madrid José L. , Fatela Lorenza V. , Sarabia Rosario , Rivas Juan J. , Gozalo Adolfo
Published: January 2009

The experience with the administration of intraventricular morphine for the control of malignant pain in 197 patients is analyzed. Small doses of morphine injected via a ventricular reservoir provided satisfactory control of otherwise intractable pain in terminal cancer patients. Complete analgesia together with a favourable behavioral response was obtained without noticeable neurological changes or side‐effects annoying or severe enough for the patients to discontinue therapy. Tolerance was much less marked than with parenteral opiates. Chronic intraventricular therapy can be safely performed on an outpatient basis by injecting the opiate once or twice a day. The method may be improved by using refillable continuous‐infusion devices and new drugs able to retain the analgesic effects of morphine while eliminating the unwanted ones.
Continuous vs. bolus epidural morphine
Authors: Oyama T. , Murakawa T. , Baba S. , Nagao H.
Published: January 2009

The clinical evaluation of continuous administration of epidural morphine was undertaken using an infusion pump (Act‐A‐Pump 1000). Eleven patients who had undergone abdominal surgical procedures were treated with this therapeutic modality for postoperative pain control, and two cancer patients for chronic pain relief. The results were satisfactory and the advantages over repeated epidural injections are discussed.
Effects of ketamine on liver blood flow and hepatic oxygen consumption. Studies in the anaesthetised greyhound
Authors: Thomson I. A. , Fitch W. , Campbell D. , Watson R.
Published: January 2009

The effects of three increasing doses of ketamine on the blood flow to, and oxygen consumption of, the liver, were studied in seven anaesthetised greyhounds. Hepatic arterial and portal venous blood flows were measured continuously using electromagnetic flow probes, and mean arterial pressure and cardiac output monitored as appropriate. Ketamine, even at the highest dose, had little effect on the blood flow to the liver: hepatic arterial blood flow and portal venous blood flow did not differ significantly from their baseline values. However, the oxygen delivery to the liver decreased due, probably, to an increase in oxygen consumption by the pre‐portal organs.
The effect of droperidol on fentanyl‐influenced gastric emptying in man
Authors: Petring O. U. , Adelhøj B. , Crawford M. , Angelo H. , Jelert H.
Published: January 2009

The effect of droperidol on gastric emptying was determined from the rate of paracetamol absorption in seven healthy adult volunteers who received fentanyl, each acting as his/her own control. On each occasion the subjects were given droperidol 2.5 mg or normal saline (placebo) i.v. in double‐blind fashion. On both occasions, 20 and 50 min later a dose of 0.0015 mg kg‐1 fentanyl was given. Ten minutes after the first fentanyl dose, the subjects ingested 20 mg kg‐1 paracetamol with 200 ml of water. Our findings demonstrate that droperidol was not able to accelerate gastric emptying in subjects receiving subsequent small doses of fentanyl. Furthermore, the delayed absorption pattern of paracetamol on both occasions suggests that gastric emptying is retarded with or without droperidol.
Assessment of the Ohio 5400 volume monitor Ohmeda SE302 spirometer and the flow meters of the Servo 900C ventilator
Authors: Synnott A. J. , Wren W. S.
Published: January 2009

The performance of the Ohio 5400 electronic anemometer and the Ohmeda SE302 heated platinum filament respirometer were assessed in a series of bench tests in which they were incorporated into the patient circuit of a Siemens‐Elema Servo 900C ventilator. The reference instrument was a Fleisch pneumotachograph. The Ohio 5400 was accurate to within 10% when measuring air flows between 23 and 44 1/min, provided the cycling frequency did not exceed 30 b.p.m. and the flow wave form was not accelerating. The Ohmeda SE302 was accurate to within 10% when measuring air flows between 8 and 48 1/min, regardless of cycling frequency or shape of respiratory wave form. Both instruments displayed marked inaccuracies (of the order of 20–30%) when measuring 100% oxygen or 66% nitrous oxide/oxygen mixtures. The performance of the flow transducer of the Servo 900C was also assessed. This was significantly superior, and its output was virtually identical to the uncorrected output of the pneumotachograph.
Comparison of costs of different anaesthetic techniques
Authors: Bengtson J. P. , Sonander H. , Stenqvist O.
Published: January 2009

The costs of anaesthetic drugs, intravenous agents as well as gases, were studied for different anaesthetic techniques in a medium‐sized operative procedure, cholecystectomy. Three anaesthetic breathing systems were used: a non‐rebreathing system, a circle absorber system with medium fresh gas flows of 3–6 1/min, and a low‐flow circle system. Anaesthesia without volatile inhalation agents used with a low‐flow technique was the least expensive, and anaesthesia with isoflurane in a non‐rebreathing system was the most expensive. The costs of anaesthesia without volatile inhalation agents in a non‐rebreathing system, enflurane anaesthesia in a circle system with medium fresh gas flows, and isoflurane anaesthesia with low‐flow technique were similar.
Measurement of acceleration: a new method of monitoring neuromuscular function
Authors: Mogensen J. Viby , Jensen E. , Werner M. , Nielsen H. Kirkegaard
Published: January 2009

A new method for monitoring neuromuscular function based on measurement of acceleration is presented. The rationale behind the method is Newton's second law, stating that the acceleration is directly proportional to the force. For measurement of acceleration, a piezo‐electric ceramic wafer was used. When this piezo electrode was fixed to the thumb, an electrical signal proportional to the acceleration was produced whenever the thumb moved in response to nerve stimulation. The electrical signal was registered and analysed in a Myograph 2000 neuromuscular transmission monitor. In 35 patients anaesthetized with halothane, train‐of‐four ratios measured with the accelerometer (ACT‐TOF) were compared with simultaneous mechanical train‐of‐four ratios (FDT‐TOF). Control ACT‐TOF ratios were significantly higher than control FDT‐TOF ratios: 116±12 and 98±4 (mean ± s.d.), respectively. In five patients not given any relaxant during the anaesthetic procedure (20–60 min), both responses were remarkably constant. In 30 patients given vecuronium, a close linear relationship was found during recovery between ACT‐TOF and FDT‐TOF ratios. It is concluded that the method fulfils the basic requirements for a simple and reliable clinical monitoring tool.
The Accelograph®: a new neuromuscular transmission monitor
Authors: Jensen E. , Mogensen J. Viby , Bang U.
Published: January 2009

A new neuromuscular transmission monitor based on measurement of acceleration is presented. The monitor consists of an acceleration transducer, i.e. a piezo‐electric ceramic wafer with an electrode on each side, and a stimulation and computing unit. The transducer can be fastened to the thumb, and when the finger is moved in response to nerve stimulation a voltage difference develops between the two electrodes. The voltage is then measured and registered in the computing unit. The acceleration transducer does not require preload, but merely that the muscle on which the measurement is being made can move freely. The accelograph is therefore easy to set up and operate. In daily clinical practice it has proved possible, using this new apparatus, to achieve reliable evaluation of the degree of non‐depolarizing neuromuscular blockade in less than 2 min.
Epidural versus combined spinal epidural block for cesarean section
Authors: Rawal N. , Schollin J. , Wesström G.
Published: January 2009

In a controlled study a single segment combined spinal epidural (CSE) block was compared with epidural block for cesarean section. Thirty healthy parturients were randomly divided into two groups. In both groups a T4 block was aimed at. Bupivacaine was used to provide analgesia in both groups. All patients receiving CSE block had good to excellent analgesia, while 11 patients (74%) receiving epidural block had similar pain relief. This was reflected in the requirement for additional analgesics, sedatives or N2O anesthesia. The muscular relaxation was also better following CSE block. The total dose of bupivacaine for a T4 block was three times larger in patients receiving only epidural block. The maternal and fetal blood bupivacaine levels were correspondingly about three times higher in the epidural group. Additionally, the incidence of maternal hypotension was higher in patients receiving epidural block. Apgar scores, blood gases and neurobehavioural evaluation did not show any differences between the two groups of neonates. No postspinal headache was noted. CSE block appears to combine the reliability of spinal block and the flexibility of epidural block while minimizing their drawbacks.
Pharmacokinetic implications for the clinical use of atropine, scopolamine and glycopyrrolate
Authors: Kanto J. , Klotz U.
Published: January 2009

Several specific and sensitive new methods for determining atropine and its metabolites in biological fluids have increased the possibility to characterise the pharmacokinetic properties of this antimuscarinic agent. Following i.v. injection, atropine disappears very quickly from the circulation, resembling its fast onset of action. Age, but not sex, appears to have a clear effect on its kinetics, explaining at least partly the higher sensitivity of very young and very old patients to this anticholinergic agent. Following i.m. or oral atropine administration, typical anticholinergic effects coincide quite well with the absorption rate of the drug, indicating that the premedication should be given about 1 and 2 h before induction of anaesthesia. A sufficient absorption after rectal administration offers an alternative treatment, especially in children. Differing from its placental transfer, atropine has a delayed and incomplete lumbar cerebrospinal fluid penetration, indicating a fundamental difference between these two biological membranes. Oropharyngeally administered atropine has a very variable absorption, but inhaled or intratracheally given drug has produced interesting new results, e.g. pulmonary atropine administration appears to have clinical significance in special situations, such as cardiac arrest and organophosphate poisoning (military personnel). Depending on the method used, different data on the metabolism and excretion for atropine have been reported and therefore further studies are needed in this respect. The pharmacokinetics of scopolamine and glycopyrrolate and their relation to clinical response are poorly understood.
Residual curarisation: a comparative study of atracurium and pancuronium
Authors: Andersen B. N. , Madsen J. V. , Schurizek B. A. , Juhl B.
Published: January 2009

Sixty patients (17–78 years old, ASA group I–II) were included in the study, which was triple–blind, randomised, stratified and controlled. Patients were selected in pairs according to sex and type of operation, and randomly allocated to one of two groups, atracurium or pancuronium. Anaesthesia was achieved with thiopentone, pethidine and nitrous oxide in oxygen, and patients were then given atracurium 0.1 mg kg‐1or pancuronium 0.6 mg kg‐1. Incremental doses were administered when clinically indicated. On recovery, residual curarisation was evaluated clinically and with the train–of–four method by a doctor who was unaware of the neuromuscular blocking agents used. Residual curarisation was found to be less after neuromuscular blockade with atracurium in the doses used in this study. Atracurium has advantages in this respect when neuromuscular monitoring is not used during operation.
Survival of intensive care patients II: outcome prediction 1 hour after admission
Authors: Zarén B. , Bergström R.
Published: January 2009

978 patients from a multidisciplinary intensive care unit (ICU) were followed prospectively to evaluate outcome. At 1 year after admission the cumulative mortality was 26.5%. Age, medical history and different condition variables 1 h after admission were included in logistic regression models in order to identify risk factors for death in the ICU and afterwards. By combining these predictive factors, it was possible to describe clinically interesting patient groups with a low and a high risk, respectively, of dying. 330 patients younger than 65 years, without any history of cancer and without any condition risk factors 1 h after admission, had a cumulative mortality of 6% at 1 year as compared to another group of patients with a 1–year mortality of 63%. In a small group of patients who had all the identified risk factors, the mortality rate at 1 year was 100%. It was also possible to identify a low–risk group of 251 patients (26%, of total) who had a risk of death in the ICU of less than 0.5% as compared to 9.6% for the average patient.
Age, fiber type composition and in vitro contracture responses in human malignant hyperthermia
Authors: ØRding H. , Hansen U. , Skovgaard L. Theil
Published: January 2009

Muscle fiber typing and in vitro contracture tests were performed in 59 patients investigated for susceptibility to malignant hyperthermia (MH). Eighteen patients were found to be susceptible to MH. There was no difference in age or fiber type distribution between MH susceptible and non–susceptible patients. No correlation was found between age and fiber type distribution. Separate analyses for each diagnostic group revealed no relationship between age or fiber type distribution and response to halothane or caffeine. When all caffeine results were pooled, however, there was a significant effect of age on the caffeine specific concentration (the concentration eliciting a contracture of 1 g), but not on the caffeine threshold concentration (the minimal concentration eliciting an increase in tension). It is concluded that age and fiber type distribution have no influence on MH diagnosis, if the protocol of the European MH Group for evaluation of susceptibility to MH is followed.
The site of action of trimethaphan–induced neuromuscular blockade in isolated rat and frog muscle
Authors: Nakamura K. , Hatano Y. , Mori K.
Published: January 2009

The present study was undertaken to determine the site of action of trimethaphan in causing neuromuscular blockade using isolated rat and frog muscle. Trimethaphan and d–tubocurarine attenuated the twitch tension developed by nerve stimulation, trimethaphan being 1/100 to 1/200 as potent as d–tubocurarine. Neostigmine potentiated the inhibitory effect of trimethaphan but reversed the effect of d–tubocurarinc. Trimethaphan shifted the dose response curve of frog rectus abdominis muscle for carbachol downwards, while d–tubocurarine shifted the curve parallel to the right. Treatment with d–tubocurarine or succinylcholine protected acetylcholine receptors from persistent blockade by a–bungarotoxin while, in contrast, trimethaphan failed to protect the receptors. The findings indicate that trimethaphan acts on the motor endplate but, unlike d–tubocurarine, does not interact with the recognition site of acetylcholine receptors; the action of trimethaphan appears to be associated with the blockade of endplate ionic channels.
Venous blood concentration of lidocaine after nasopharyngeal application of 2% lidocaine gel
Authors: Nvdahl P. A. , Axelsson K.
Published: January 2009

In 34 subjects undergoing topical anaesthesia with lidocaine gel (2% xylocaine gel), the concentrations of lidocaine base were measured in repeated venous blood samples. Twenty–three patients (Group I) were given 20 ml of 2% lidocaine gel (400 mg of lidocaine) and six subjects (Group II) 40 ml of 2% lidocaine gel (800 mg of lidocaine) nasopharyngeally, the gel reaching the pharynx being swallowed. Five minutes after administration of the gel, a gastric tube was introduced via the nasal cavity. In six patients (Group III), the bladder was catheterised in addition to insertion of a gastric tube. Before the catheter was introduced, these patients were given lidocaine gel nasopharyngeally (400 mg) and endourethrally (400 mg). After the introduction of the gastric tube, all subjects (except four volunteers in Group II) were given general anaesthesia. Before intubation, the patients in Group III also received lidocaine spray laryngotracheal^ (50 mg; 10% xylocaine spray). The initial absorption of lidocaine was rapid, although the blood concentrations were low. The mean peak concentrations (Cmax) of lidocaine in the three groups were 0.57, 1.39 and 0.73 μg/ml, respectively. The blood concentration in Group II was significantly higher than those in Groups I and III. The mean length of time between the nasopharyngeal application of lidocaine gel and the time when Cmax was reached (tpeak) was the same in all three groups (60–70 min). In all subjects 400–800 mg of lidocaine gel gave good analgesia for insertion of a gastric tube. A dose in excess of 400 mg gave no extra benefit, however, The maximal recommended dose of 2% lidocaine gel, 400 mg, applied nasopharyngeally gives a low blood concentration which is only one–eighth of that reported to be associated with toxic reactions in man.
Pulmonary artery pressure: flow relationships in hyperoxic and in hypoxic dogs
Authors: Leeman M. , Lejeune P. , Mélot C. , Deloof T. , Naeije R.
Published: January 2009

Methylprednisolone has been reported to impair hypoxic pulmonary vasoconstriction in isolated lungs, possibly by inhibiting the generation of vasoconstricting products of arachidonic acid metabolism. We investigated the effects of methylprednisolone on mean pulmonary artery pressure (PAP): cardiac index (Q) relationships in intact pentobarbital anaesthetized dogs ventilated alternatively in hyperoxia (fraction of inspired O2, Fio2 0.4) and in hypoxia (Fio2 0.1). Cardiac output was increased by opening an arterio–venous femoral fistula or reduced by stepwise inflations of a balloon in the inferior vena cava. Five point PAP: Q relationships were found to be rectilinear in all experimental conditions. Over the entire range of Q_ studied (2 to 5 1/min–m2), hypoxia increased PAP in seven dogs (“responders”) and did not affect PAP in three other dogs (“non–responders”). A hypoxic pulmonary pressor response was restored in these three “non–responders” by administration of 1 g acetylsalicylic acid iv. Methylprednisolone 30 mg/kg iv had no effect on hyperoxic and on hypoxic pulmonary vascular tone in the “responders” and in the “non–responders” treated with acetylsalicylic acid. An additional dog pretreated with methylprednisolone 30 mg/kg iv 24 h before the experiment still had a marked hypoxia–induced increase in PAP over the entire range of Q_ studied. Thus a large dose of methylprednisolone does not affect hypoxic or hyperoxic pulmonary vascular tone in intact dogs. These data do not support the hypothesis that products of arachidonic acid metabolism mediate hypoxic pulmonary vasoconstriction.
Superoxide dismutase and catalase failed to improve neurologic outcome after complete cerebral ischemia in the dog
Authors: Forsman M. , Fleischer J. E. , Milde J. H. , Steen P. A. , Michenfelder J. D.
Published: January 2009

Superoxide dismutase (SOD) and catalase, natural scavengers of free oxygen radicals, or saline were administered as a continuous systemic infusion to 12 dogs, in a blind randomized fashion, starting 10 mm prior to a 10;min episode of complete cerebral ischemia, and continued thereafter for 60 min. Reversible complete cerebral ischemia was achieved by simultaneously occluding the ascending aorta and venae cavae. There were no significant differences in physiological variables (arterial blood gases, hemoglobin, mean arterial blood pressure, heart rate, and temperature) between the two groups, either pre–ischemia or post–ischemia. There was no significant difference in neurologic outcome when evaluated at 48 h post–ischemia. It has previously been reported that the same dose of SOD and catalase as used in the current study could reduce infarct size by 50% when given systemically before reperfusion following coronary ischemia in dogs. The lack of a measurable effect on neurologic outcome in our cerebral ischemic modelmight be because of the failure of the free oxygen radical scavengers to reach the ischemic cells in sufficient amounts, or because free oxygen radicals do not contribute to brain injury following complete cerebral ischemia.
Barbiturate anaesthesia does not cause pulmonary densities in dogs: a study using computerized axial tomography
Authors: Lundquist H. , Hedenstierna G. , Ringertz H.
Published: January 2009

The occurrence of roentgenological densities in dependent lung regions was studied in 28 mongrel dogs (mean weight 18.7 kg) during barbiturate anaesthesia and mechanical ventilation. The densities were analysed by means of computerized tomography, permitting transaxial projections of the thorax. Two dogs showed small densities in dependent lung regions, corresponding to 1% of the total intrathoracic area. In five dogs there were small areas of probably increased density, without sharp delineation, in dependent regions. The remaining 21 dogs (75%) exhibited no densities. The frequency of such densities was thus much lower than has been found in anaesthetized human subjects. Moreover, the densities were relatively smaller than those in man and qualitatively different. It is concluded that the development of dependent lung densities differs both quantitatively and qualitatively between dogs and human subjects.
Respiratory effects of nitrous oxide during halothane or enflurane anaesthesia in children
Authors: Murat I. , Bret F. Le , Chaussain M. , Maurice CL. Saint
Published: January 2009

The respiratory effects of nitrous oxide (N2O) were studied during halothane and enflurane anaesthesia in 12 children (mean age 46.4 ± 29.3 months, mean weight 15.3 ± 4.2 kg) during surgery under continuous extradural anaesthesia. Four equipotent anaesthetic states were studied in random order: 1) halothane 1 MAC in oxygen, 2) halothane 0.5 MAC + 50% NaO, 3) enflurane 1 MAC in oxygen, 4) enflurane 0.5 MAC + 50%N2O. End–tidal fractions of CO2, (Petco2) and halothane and enflurane were measured using infrared analysers. The respiratory variables (tidal volume VE, minute ventilation VE, respiratory frequency F, inspiratory time Ti, mean inspiratory flow Vi, effective inspiratory time Ti/Ttot) were measured using a pneumotachograph. Significant changes were observed between the four states for VE, VI, F and Pelco2, whereas the values of VT, Ti and Ti/Ttot did not differ significantly. The respiratory depressant effect of 1 MAC of either halothane alone or of the mixture of halothane and N2O was very similar. During enflurane anaesthesia, PetC02 was less increased when N2O was substituted for enflurane, owing to a significant increase in respiratory frequency. A marked decrease in VE together with an increase in Petco2 was observed during enflurane anaesthesia (states 3 and 4) when compared to the corresponding states during halothane anaesthesia (states 1 and 2). The respiratory depressant effect of enflurane is greater than that of halothane in unpremedicated children, even when substituting N2O for an equal MAC fraction of enflurane. The eflect of N2O on respiratory patterns seems to depend on the inhalational agent used and/or on the resting respiratory frequency.
Effects of isoflurane on myocardial metabolism during postischaemic reperfusion in the rat
Authors: Kashimoto S.
Published: January 2009

In experiments on isolated rat heart lung preparation, the effects of isoflurane on myocardial metabolism during postischaemic reperfusion were evaluated with intramyocardial high energy phosphates, lactate and glycogen. Hearts were perfused for 10 min initially and made globally ischaemic for 8 min in ischaemic groups. Afterwards, they were reperfused for 12 min. Isoflurane was administered from 5 min after the start of perfusion to the end of reperfusion. There was no significant difference in myocardial lactate levels between ischaemic isoflurane and control groups. However, the ATP level in the hearts in the ischaemic isoflurane group was significantly higher than that in the ischaemic control group (17.96 ±1.31 vs 15.50 ± 0.87; P < 0.005). The administration of isoflurane to the isolated rat heart during pre– and post–ischaemia enhanced metabolic recovery in the postischaemic state.
Ventilation and ventilatory response to carbon dioxide during caudal anaesthesia with lidocaine or bupivacaine in sedated children
Authors: Takasaki M.
Published: January 2009

Resting ventilation, arterial blood–gas tensions and the ventilatory response to carbon dioxide were measured in sedated children before and after caudal anaesthesia using 10 mg– kg‐1 of 1.5% lidocaine or 3.3 mg kg‐1 of 0.5% bupivacaine. Expired minute volume decreased slightly after both caudal blocks but end–tidal Pco2 increased slightly after caudal block with lidocaine. No clinical changes in PaCO2 and Pao2 were observed in either group. The slope of the CO2 response curves increased significantly after both caudal blocks. The mean plasma levels oflidocaine and bupivacaine were 3.95 ± 0.64 (s.d.) and 1.33 ± 0.29 μg ml‐1, respectively. These results indicate that the ventilatory response to hypercapnia is markedly improved by the two caudal blocks, but resting ventilation is slightly impaired by caudal block with lidocaine, and from the aspect of pulmonary ventilation bupivacaine is better than lidocaine for caudal anaesthesia.
Thiopentone reduces the haemodynamic response to induction of high–dose fentanyl–pancuronium anaesthesia in coronary artery surgical patients
Authors: Takkunen O. , Meretoja O. A.
Published: January 2009

Thirty–three coronary artery bypass graft patients anaesthetized with high–dose fentanyl (50 μg/kg)–pancuronium–oxygen were divided into one control group receiving additional saline and two groups receiving additional 1 mg/kg or 2.5 mg/kg of thiopentone before laryngoscopy and intubation. During laryngoscopy and intubation, systemic arterial pressures, heart rate and rate–pressure–product remained at considerably elevated levels caused by pancuronium in the control group. Both doses of thiopentone reduced these haemodynamic. values close to their initial levels. Cardiac index and left ventricular stroke work index were significantly decreased, especially by the higher thiopentone dose, as compared with the control group. However, there were no statistical differences between the haemodynamic changes produced by the two doses of thiopentone. Sedative or hypnotic supplementation of high–dose fentanyl anaesthesia seems to be necessary if pancuronium is used as a muscle relaxant. A small increment of thiopentone, 1 mg/kg, was enough to return haemodynamic parameters almost to their initial levels, whereas the effect of 2.5 mg/kg of thiopentone was unnecessarily strong.
Cardiac function and sympathoadrenal activity in the newborn after cesarean section under spinal and epidural anesthesia
Authors: Hägnevik K. , Irestedt L. , Lundell B. , Sköldefors E.
Published: January 2009

Left ventricular systolic time intervals, bupivacaine concentrations, adrenaline and noradrenaline levels were determined in 19 neonates delivered by elective cesarean section. Ten of the cesarean sections were performed under spinal and nine under epidural anesthesia. Plain bupivacaine 0.5% was used for the epidural anesthesia and bupivacaine 0.5% in glucose 8% for the spinals. The noradrenaline and adrenaline levels were higher in the neonates whose mothers received epidural anesthesia. The differences in catecholamine and bupivacaine concentrations were not associated with differences in left ventricular dynamics, or the timing of postnatal circulatory changes. The significant exposure of the neonate to bupivacaine, at maternal epidural anesthesia, seems to have no negative effect on early neonatal circulation in the healthy term infant.
Treatment of terminal cancer pain in Finland. A questionnaire survey
Authors: Vainio A.
Published: January 2009

A questionnaire concerning current practice in the treatment of cancer pain was sent to 783 Finnish physicians. This study is based on the replies from 421 physicians who stated that they at least sometimes see cancer patients. Three simulated patient cases were presented in the questionnaire, and the adequacy of the treatment suggestions was evaluated. The results indicated that drugs predominate in the treatment of cancer pain. The suggested doses of narcotic analgesics were well below the minimum effective daily doses. As many as half of the physicians failed to use the therapeutic modalities correctly, irrespective of the frequency of their seeing cancer patients. Education in effective pain treatment should therefore be intensified to ascertain that all physicians involved in clinical practice have satisfactory knowledge of the treatment of cancer pain.
Antagonism of flunitrazepam–induced sedative effects by flumazenil in patients after surgery under general anaesthesia. A double–blind placebo–controlled investigation of efficacy and safety
Authors: Skeie B. , Emhjellen S. , Wickstrøm E. , Dodgson M. S. , Steen P. A.
Published: January 2009

This study aimed to assess the efficacy and safety of flumazenil and a placebo in reversing the residual effects of flunitrazepam used to induce anaesthesia for elective laparoscopy in 49 female patients aged 16 to 52 years. In contrast to the placebo, flumazenil gave reductions in amnesia, sedation score, mood rating for mental sedation and physical sedation, and time taken to complete a psychomotor performance test which lasted throughout the study. There were no significant changes in pulse rate, respiration rate or blood pressure, and no unwanted effects were attributed to flumazenil.
Intermittent high frequency ventilation: a new mode to measure changes in lung volume and alveolar gas concentration, enhance CO2 elimination and reduce intrapulmonary pressures
Authors: Chakrabarti M. K. , Swenzen G. O. , Whitwam J. G.
Published: January 2009

A new method of artificial ventilation, intermittent high frequency ventilation (IHFV), is described in which high frequency ventilation (HFV) is intermittently interrupted so that short periods of ventilation and pauses in ventilation occur in sequence several times a minute. During the pauses in ventilation the increase in lung volume, which occurs during the short periods of HFV, is either exhaled completely or to a predetermined level which prevents sustained hyperinflation of the lungs but allows the maintenance of PEEP if required. The volume of gas expired during the ventilation pauses, i.e. gas retained during the periods of HFV, is measured. When this trapped gas is exhaled completely, the mean airway and compliance pressures are reduced by up to 50% compared to continuous HFV at the same frequency, inspiration:expiration (I:E) ratio and low tidal volume (VT). The alveolar CO2 concentration was measured in gas expired towards the end of the pauses in ventilation. CO2 elimination was improved, especially at high frequencies of ventilation, which allowed a further reduction in inflation pressures while maintaining a constant Paco2.
The Venflon cannula as a sideport of infection
Authors: Cozanitis D. A. , Ojajärvi J. , Måkelä P.
Published: January 2009

The possible role of infection through the valved sideport of Venflon cannulae was evaluated by one individual who followed an identical procedure of placing a syringe into the sideport and injecting saline solution. Basic aseptic techniques were used in a contaminated, busy environment. No bacterial growth was found in either anaerobic or aerobic culture media following a total of 1500 injections. The experiment shows that if the measures used could be applied, infection through the sideport would be minimal.
Cerebral blood flow, cerebral metabolic rate of oxygen and relative CO2 reactivity during neurolept anaesthesia in patients subjected to craniotomy for supratentorial cerebral tumours
Authors: Cold G. E. , Christensen K. J. S. , Nordentoft J. , Engberg M. , Pedersen M. Bach
Published: January 2009

In 10 patients subjected to craniotomy for supratentorial cerebral tumours in neurolept anaesthesia, cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRo2) were measured twice peroperatively by a modification of the Kety & Schmidt technique, using 133Xe. The relative CO2 reactivity was assessed indirectly as the % change of the arterio–venous oxygen difference (AVDo2) per mm change in Paco2. The patients were premedicated with diazepam 10–15 mg perorally. For induction, thiopentone 4—‐6 mg/kg, droperidol 0.2 mg/kg and fentanyl 5 μg/kg were used, and for maintenance N2O 67% and fentanyl 4 μg/ kg/h. During the first flow measurement the median and range of CBF was 30 ml/100 g/min (range 17–45), of AVDo2 8.0 vol % (range 4.1–9.5), and of CMRo2 2.28 ml O2/100 g/min (range 1.57‐2.84). During tin–second CBF study, AVDo2 increased to 9.3 vol % (range 3.4–11) (P < 0.05), and CMRo2 increased to 2.51 ml O2/100 g/min (range 1.88‐3.00) P < 0.05, while CBF was unchanged. The CO2 reactivity was present in all studies, median 1.8 %/mmHg (range 0.5–15.1). The correlation coefficients between jugular venous oxygen tension/saturation, respectively, and CBF were high at tensions/saturations exceeding 4.0 kPa and 55%, indicating that hyperperfusion is easily unveiled by venous samples from the jugular vein during this anaesthesia.
Effects of halothane on membrane potentials and membrane ionic currents in single bullfrog atrial cells
Authors: Hirota K. , Y. Ito M.D.  , Momose Y.
Published: January 2009

Halothane exerts negative inotropic and negative chronotropic actions on the isolated heart in experimental animals. In order to assess directly the actions of halothane in myocardium, we studied the effects of halothane on membrane potentials and transmembrane ionic currents in single isolated frog atrial cells obtained by the enzymatic dissociation method. The results show: (a) that the action potential is prolonged and its plateau phase and overshoot are depressed, but the resting potential remains unchanged; (b) that there is a significant inhibition of a time– and voltage–dependent outward K+ current and a slow inward Ca2+ current, with a slight decrease of a fast inward Na+ current following halothane (1.0–4.0%) application; and that halothane has no effect on another K+ current, time–independent current.
Comparison between a new acceleration transducer and a conventional force transducer in the evaluation of twitch responses
Authors: Itagaki T. , Tai K. , Katsumata N. , Suzuki H.
Published: January 2009

An acceleration transducer elicits an output voltage proportional to the deformation of the piezo crystal, in accordance with the twitch responses of the applied fingers. The reliability of such a transducer was evaluated by comparing induced twitch responses with those from a force transducer applied on the contralateral arm of an individual during neuromuscular block with vecuronium. The results obtained from twitch responses with the acceleration transducer during neuromuscular block were almost identical to those obtained with the force transducer. Also, the twitch heights due to acceleration of the examined thumb correlated extremely well with the twitch height due to twitch tension with the force transducer. It is concluded that the acceleration transducer may be a useful and reliable device for monitoring neuromuscular block, although responses during tetanic stimulation such as tetanic fade cannot be determined by the transducer.
Should oxygen be administered after laparoscopy in healthy patients?
Authors: Vegfors M. , Cederholm I. , Lennmarken C. , Löfström J. B.
Published: January 2009

This study aimed to assess the oxygen flow necessary to maintain satisfactory oxygen saturation when administered via a nasopharyngeal catheter. Oxygen saturation was displayed by a pulse oximeter and/or measured in arterial blood samples. Thirty–six healthy women scheduled for elective diagnostic laparoscopy were anaesthetized using thiopentone, fentanyl and O2/N2O. Atracurium was used as relaxant which was reversed with atropine and neostigmine. Arterial samples were obtained prior to anaesthesia, on arrival in the postoperative ward and 1 h postoperatively. Oxygen saturation was monitored postoperatively using a pulse oximeter. The patients were randomly divided into three groups which received either no oxygen, 2 1 O2/min or 4 1 O2/min. On arrival in the postoperative ward 15% of the patients were below the normal limit of O2 saturation (94%). In patients receiving 2 1 or 4 1 O2, oxygen saturation was well above normal values. In patients receiving no oxygen, two had low oxygen saturation (92% and 93%). Comparing saturation values obtained in arterial samples with values measured with pulse oximetry gave r = 0.79. It is concluded that all patients should be given oxygen in the immediate postoperative period. Increasing oxygen flow from 2 to 4 1/min had no major effect on oxygen saturation. These results were obtained in healthy patients following minor abdominal surgery.
Effect of total intravenous anaesthesia with midazolam/alfentanil on the adrenocortical and hyperglycaemic response to abdominal surgery
Authors: Nilsson A. , Persson M. P. , Hartvig P. , Wide V. L.
Published: January 2009

The effect of anaesthesia on the hyperglycaemic and adrenocortical response induced by surgery was studied in patients undergoing abdominal hysterectomy. The study group was anaesthetized with midazolam and alfentanil using a totally intravenous anaesthetic technique. A reference group received anaesthesia with thiopentone, alfentanil and nitrous oxide. Midazolam 0.42 mg · kg‐1 was given as a loading infusion followed by a maintenance infusion of 0.125 mg·kg‐1 ·h‐1. Alfentanil was given as a bolus dose of 0.075 mg·kg‐l in both groups, followed by a loading infusion of 0.3 mg·kg‐1· h‐l for 15 min and a maintenance infusion of 0.065 mg·kg‐1·h‐1. Increments of alfentanil were given whenever heart rate or systolic blood pressure exceeded pre–induction values by more than 10%. During anaesthesia mean arterial pressure and heart rate were similar in both groups and there was no difference in alfentanil requirement. An immediate increase in blood glucose concentrations was seen following incision, but maximum concentrations were measured in the early postoperative period. Serum Cortisol concentrations decreased after induction of anaesthesia. During surgery they returned to pre–induction values, and in the postoperative period they increased to about twice the pre–induction values. It is concluded that midazolam/alfentanil anaesthesia is as effective as anaesthesia induced by thiopentone, alfentanil and nitrous oxide in suppressing the stress–response to surgery until the postoperative period. No signs of prolonged adrenocortical depression were observed.