bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivopotentiation of atracurium neuromuscular blockade by nimodipine in rabbits
Authors: Gómez‐Iglesias E. , García E. , Suarez E. , Martínez R. , Rodríguez‐Sasiaín J. M. , Calvo R.
Published: January 2009

The interaction between nimodipine, a calcium channel blocker, used for the treatment of subarachnoid haemorrhage, and atracurium, was studied in rabbits. An intravenous dose of 0.1 mg±kg‐1of nimodipine given over 3 min caused a potentiation of the neuromuscular blocking action of atracurium (administered at an infusion rate of 7.5 μg±kg‐1±min‐1), measured on the indirectly stimulated tibialis‐anterior muscle of the animal. (ED50)infand (ED95)infwere significantly reduced (30.7% and 23.3%) in nimodipine‐treated animals (P<0.05 andP<0.02, respectively). No changes were observed in recovery rate.
A new ventilator converter with the Siemens Servo Ventilator ‐ evaluation in a lung model
Authors: Hesselvik J. F. , Bengtsson M. , Johnson A.
Published: January 2009

A ventilator converter device (Anmedic) for connecting a non‐rebreathing ventilator (Servo Ventilator 900 B; Siemens‐Elema) to a circle anaesthesia system was evaluated in a lung model. Recorded minute ventilation was slightly lower than dialled in most cases. We furthermore found inadequate expiratory expansion of the ventilator converter bellows, with progressive loss of tidal volume and consequently recorded minute volume, when fresh gas flow to the circle system was low (1 l±min‐1), expiratory time was short (<40%) and respiratory obstruction was present.
Diazepam and atropine as premedicants: no discrimination by monoamine metabolite and catecholamine measurements in cerebrospinal fluid and plasma
Authors: Kanto J. , Scheinin M.
Published: January 2009

The relationships between self‐reported assessments of the quality of the preoperative night's sleep, preoperative anxiety, and several biochemical and physiological indicators of stress reaction were investigated in pregnant women at term receiving no premedication (n = 15), a placebo tablet (n = 15), diazepam 5 mg p.o. (n = 15), or atropine 0.01 mg/kg i.m. (n = 15), in connection with spinal analgesia for elective caesarean section. In the patients receiving no premedication, the subjective estimate of the quality of the preoperative night's sleep was negatively associated with concentrations of noradrenaline (NA) and its metabolite, 3‐methoxy‐4‐hydroxyphenylglycol (MHPG) in CSF, and with plasma adrenaline. The anxiolytic effect of diazepam was reflected as significantly lower plasma levels of another metabolite of NA, 3,4‐dihydroxyphenylglycol (DHPG). Placebo and diazepam, and to a lesser extent atropine, confounded the statistical relationships between the clinical and biochemical responses found in the patients with no premedication. On the whole, the biochemical monoamine measurements were of little use in determining the clinical effects of different kinds of premedicants.
Labetalol attenuates the negative effects of deliberate hypotension induced by isoflurane
Authors: Toivonen J. , Virtanen H. , Kaukinen S.
Published: January 2009

The effect of labetalol on deliberate hypotension was studied in 24 adult patients undergoing middle‐ear surgery. Hypotension was induced in Group I (12 patients) with isoflurane 3.0 vol% in inspiratory gas, and in Group II (12 patients) with labetalol 0.5 mg±kg‐1 i.v., in addition to isoflurane. The induction time of hypotension was 4.9±1.0 (s.e. mean) min in Group I, and 1.8±0.2 min in Group II (P<0.01). The mean isoflurane concentration in inspiratory gas for the maintenance of hypotension was 1.4±0.2 vol% in Group I, and 0.7±0.1 vol% in Group II (P<0.01). There were no differences in urine flow rates (UF) between the groups during any phase, though UF decreased in Group I from the prehypotensive value 0.58±0.12 ml±min‐1 to 0.07±0.02 ml±min‐1 during hypotension (P<0.01) and increased to 1.28±0.17 ml±min‐1 after anaesthesia (P<0.05). UF in Group II were 0.56±0.17, 0.25±0.10 and 0.56±0.06 ml±min‐1, respectively. Creatinine clearances per 1.73 m2 body surface area (CCreat) in Group I were 78±14 ml±min‐1, and in Group II 78±11 ml±min‐1 before hypotension. During hypotension, CCreat were lower in Group I (8±1 ml±min‐1) than in Group II (33±8 ml±min‐1) (P<0.01). After anaesthesia, there was no difference in CCreat between the groups (Group I: 110±17 ml±min‐1 and Group II: 120±17 ml±min‐1). The results indicate that labetalol has a favourable effect on deliberate hypotension induced by isoflurane.
Treatment of terminal cancer pain in Finland: a second look
Authors: Vainio A.
Published: January 2009

A questionnaire concerning the treatment of cancer pain was sent to 10% and 5% random samples of Finnish physicians in 1985 and in 1990, respectively. The physicians were asked about their current practice in the treatment of pain in their cancer patients, and about their main clinical problems when treating pain. Three simulated patient cases were presented, and the adequacy of the suggestions for therapy was evaluated. The results indicated that Finnish physicians had adopted a more rational and effective analgesic therapy during the 5‐year period. Treatment suggestions for the simulated patient cases had improved both in terms of daily doses of analgesics and of dose intervals, but the doses of opioids were still below those commonly used in chronic cancer pain. The clinical difficulties experienced by the physicians had changed: instead of being frustrated by the inefficacy of their treatment as in 1985, physicians were now working on the problem of finding a suitable preparation and dosage. The results suggest that the voluntary activity of patient organizations, a few pain clinics, and a few clinicians interested in pain treatment have been able to improve the practising physicians' theoretical knowledge in 5 years. In contrast to the improvement in the knowledge and skills, changing attitudes takes much longer. As many as 39% of physicians who see cancer patients at least occasionally, reported that they still had not acquired the prescription sheets necessary to prescribe opioids to outpatients.
Pain after thoracic surgery
Authors: Kalso E. , Perttunen K. , Kaasinen S.
Published: January 2009

In order to evaluate postoperative pain treatment following thoracic surgery, 214 medical records of patients who were operated during 1986–1988 were examined. Nurses' comments concerning pain and the amounts of analgesics given during the 2 postoperative days were recorded. The 150 patients who were still alive in December 1989 were sent a postal questionnaire which asked about the pain and the efficacy of pain relief they had received after their operation. They were also asked if they still had pain which they connected to the thoracotomy and if any attempts had been made to treat that pain. The mean consumption of intramuscular oxycodone was 38 mg during the 1st and 33 mg during the 2nd postoperative day. The administration of nonsteroidal anti‐inflammatory drugs significantly reduced the opioid consumption on the second but not on the first postoperative day. In 30% of the patients' charts there were no remarks on pain, in 10% there was a mention of no pain, in 40% pain was mentioned and in 20% the patient was reported to have severe pain. During the first postoperative week little pain was experienced by 60% of the patients, considerable pain by 35% and excruciating pain by 5% of the patients being interviewed. The postoperative pain relief was rated as good in 60% of the answers, satisfactory in 38% and poor in 2%. Persistent post‐thoracotomy pain lasting for more than 6 months was reported by 44% of the patients, of whom 66% had received treatment for the pain.
Use of ketamine in acute severe asthma
Authors: Sarma V. J.
Published: January 2009

Two patients with acute severe asthma, who failed to respond to conventional therapy, were given intravenous ketamine in sub‐anaesthetic doses with good results. A bolus dose of 0.75 mg/kg was followed by the same dose over 10 min with relief of bronchospasm in both cases. An infusion of ketamine at a rate of 0.15 mg/kg/h was used in each case to prevent recurrence of bronchospasm. Intravenous ketamine can be used to relieve acute intractable bronchospasm provided expert anaesthetic help is at hand. A review of the literature concerning its use in such situations is also presented.
Sedation for bronchofiberoscopy: comparison between propofol infusion and intravenous boluses of fentanyl and diazepam
Authors: Randell T.
Published: January 2009

Two methods of sedation were evaluated in unpremedicated patients undergoing elective bronchofiberoscopy. The patients were randomly allocated to receive either propofol infusion 1 mg kg‐1 h‐1 preceded by a 1 mg kg‐1 bolus (15 patients) (the propofol group) or intravenous fentanyl 1 μg kg‐1 and diazepam 0.05 mg kg‐1 (15 patients) (the fentanyl + diazepam group). Thirteen patients were treated twice during the study period and sedated with both methods (the first treatment according to random order and the second with the method not used on the first occasion). A topical anaesthetic was applied to the selected nostril with two cotton swabs soaked in 4% lidocaine. Epiglottis, vocal cords, trachea and bronchi were anaesthetized by spraying 4% lidocaine through the working channel of the fiberoscope as the instrument was advanced. The patients in the propofol group were more sedated than those in the fentanyl + diazepam group (P<0.01). The working conditions were the same. After sedation, respiratory frequency decreased only in the fentanyl + diazepam group (P<0.05). Before sedation, haemoglobin saturation of oxygen was 95 ± 2% (mean ± s.d.) in the propofol group and 94 ± 3% in the fentanyl + diazepam group. Immediately before the start of bronchofiberoscopy, it was 89 ± 4% and 90 ± 3%, respectively. The decrease was statistically significant in both groups (P<0.001). After sedation, systolic arterial pressures (SAP) decreased in both groups (P<0.01). Compared to values immediately before starting bronchofiberoscopy, SAP increased during the procedure in both groups (P<0.05). A significant increase (P<0.05) in heart rate was noted in both groups. The patients recovered in 30 min after the end of bronchofiberoscopy. There were no significant differences in recovery between the groups.
Reported anaesthetic complications during an 11‐year period. A retrospective study
Authors: Wang L. P. , Hägerdal M.
Published: January 2009

Retrospectively 120 anaesthetic complications with potential medicolegal consequences were reviewed. Seven deaths occurred. Eighty percent of the complications were potentially avoidable. Of the complications 4.4% resulted in major morbidity and 82.3% in intermediate morbidity. Dental injuries were reported with an annual frequency of six. The use of pulse oximetry and/or capnography could possibly have prevented 18% of all complications apart from dental injuries. Ten cases were reported to the National Swedish Board of Health and Welfare; four cases resulted in disciplinary consequences. The influence of human factors on the development of complications is stressed.
Spinal sufentanil in rats: part II: effect of adding bupivacaine to epidural sufentanil
Authors: Vercauteren M. , Meert T. F. , Boersma F. , Melis W. , Adriaensen H.
Published: January 2009

Male Wistar rats were injected epidurally with various doses of sufentanil, bupivacaine or sufentanil combined with bupivacaine either 40 or 80 μg. Addition of 80 μg bupivacaine to sufentanil produced a 2.2‐ to 3‐fold decrease of the lowest ED50 for a tail withdrawal reaction latency >6 and ± 10 s. The potentiation was already present at low doses. Whereas both 0.16 μg sufentanil and 80 μg bupivacaine were inactive, the combination of the two drugs resulted in a deep analgesia in all animals. Because the addition of low doses of bupivacaine to sufentanil did not increase the ED50's for side‐effects, higher specificity ratios were obtained as compared to sufentanil given alone. These results were discussed with regard to the potentiation of the analgesic properties of epidurally administered lipophylic opioids by local anaesthetics.
Estimation of total body fluid shifts between plasma and interstitium in man during extracorporeal circulation
Authors: Koller M.‐E. , Bert J. , Segadal L. , Reed R.K.
Published: January 2009

Fluid transport between plasma and interstitium during extracorporeal circulation was studied in seven patients undergoing aortocoronary bypass grafting. The absolute shifts in plasma volume during hypothermia were determined as the difference between input and loss of fluid and the changes in blood volume. The change in haemoglobin concentration due to acute haemodilution when starting extracorporeal circulation was used to calculate the absolute blood and plasma volume. The Starling equation for exchange across the capillary wall was used to describe fluid shifts. The total fluid filtered during the 60‐ to 90‐min period of extracorporeal circulation averaged 34.1 ± 11.1 (s.d.) ml/min. The total body filtration coefficient from the Starling relationship averaged 0.046 ± 0.012 ml/kg ± mmHg ± min (0.354 ± 0.092 ml/kg ± kPa ± min). Haemodilution, reducing colloid osmotic pressure in plasma (COPP) by approximately 10 mmHg (1.3 kPa) will result in a loss of plasma fluid of around 2 1 per hour. When corrected for lower fluid viscosity due to hypothermia during extracorporeal circulation, CFC would be about 40% higher, and a filtered volume of nearly 31 in a normothermic 70‐kg person would be expected. Crystalloid haemodilution for shorter periods of time does not produce excessive oedema and thus may be well tolerated.
Interaction of ORG 9426 and some of the clinically used intravenous anaesthetic agents in the cat
Authors: Khuenl‐Brady K. S. , Agoston S. , Miller R. D.
Published: January 2009

The interaction of ORG 9426, a new non‐depolarizing neuromuscular blocking agent, with intravenous anaesthetic drugs (fentanyl, thiopental, midazolam, droperidol and etomidate) has been investigated in cats. During an infusion of one of the above anaesthetics, the ED95 dose was determined by titration, and thereafter muscle relaxation was maintained with four subsequent doses of ORG 9426. Neither the potency nor the duration of action of the first dose nor that of the maintenance doses of ORG 9426 differed from those observed in a control group of cats anaesthetized with intraperitoneally administered pentobarbital. The recovery rates were similar in all groups. The authors conclude that, under the conditions of this study, commonly used intravenous anaesthetic drugs are not likely to influence the neuromuscular blocking potency and time course of action of ORG 9426 to any appreciable degree.
Variations in blood platelet‐activating‐factor levels after protamine reversal of heparin in humans
Authors: Nathan N. , Denizot Y. , Feiss P. , Cornu E. , Benveniste J. , Arnoux B.
Published: January 2009

The potent inflammatory mediator PAF‐acether (PAF = platelet‐activating factor) can produce the same hemodynamic and hematological effects as protamine infusion. In 10 patients, blood PAF and precursor levels were measured in the left atrium, the pulmonary and the radial artery before and after protamine reversal of heparin during coronary artery bypass graft. Blood PAF level in the left atrium increased 6‐fold (17 ± 12 pg ± ml‐1vs98 ± 46 pg ± ml‐1,P= 0.03) after protamine infusion. By contrast, a 4‐fold decrease was observed in the pulmonary artery blood (130 ± 48 pg ± ml‐1vs31 ± 23 pg ± m‐1,P= 0.03) and a 9‐fold decrease was noted in the radial artery blood (285 ± 104 pg ± ml‐1vs31 ± 15 pg ± ml‐1,P= 0.01). No cardiovascular impairment was observed but all patients exhibited thrombocytopenia. After protamine, PAF in the left atrium reached lower levels than those observed in the pulmonary and radial artery before protamine infusion. Moreover, no significant correlation was observed between platelet counts and PAF levels. Thus PAF seems not to mediate the platelet drop induced by heparin‐protamine complexes. A positive correlation was obtained between leukocyte counts in the pulmonary artery and PAF levels in the left atrium (r = 0.78,P= 0.02). Protamine infusion may stimulate PAF biosynthesis by leukocytes in the lung, on the one hand, and accelerate the disappearance of PAF in the arterial bed, on the other hand.
An outbreak of Klebsiella oxytoca septicemias associated with the use of invasive blood pressure monitoring equipment
Authors: Ransjö U. , Good Z. , Jalakas K. , Kühn I. , Siggelkow I. , Åberg B. , Anjou E.
Published: January 2009

Seven cases of septicemia with piperacillin‐resistant Klebsiella oxytoca (PRKO) occurred at 2‐monthly intervals in a thoracic surgery intensive care unit. All PRKO isolates were serotyped, and phenotyped with a biochemical typing system. Only one patient in the unit was found to be colonized in stool or respiratory tract with PRKO, and this strain was different from the septicemia strains in phenotype though not in serotype. Environmental cultures, from humidifiers, oxygenators, pressure transducers, etc. were negative. PRKO of the epidemic phenotype was recovered from several non‐patient transducer domes. The outbreak ended when transducer heads were disinfected and the use of non‐patient domes was abolished.
Pharmacokinetics of clonidine after epidural administration in surgical patients. Lack of correlation between plasma concentration and analgesia and blood pressure changes
Authors: van Essen E. J. , Bovill J. G. , Ploeger E. J. , Houben J. J. G.
Published: January 2009

The pharmacokinetics of epidural clonidine 150 μg was studied in 13 patients who had undergone abdominal hysterectomy. Plasma clonidine concentrations were measured up to 19 h in eight patients. In another five patients frequent blood sampling was performed only during the first 20 min to define early vascular uptake better. Peak plasma clonidine concentrations of 1.08 ± 0.35 ng ml‐1(mean ± s.d.) were reached between 5 and 10 min after injection. Plasma elimination half‐life was 829 ±157 min and plasma clearance was 177 ± 28 ml min‐1. There was a significant decrease in arterial blood pressure within 10 min of the injection of clonidine. The maximum decrease in systolic blood pressure, from a pre‐injection value of 135 ± 24.7 to 99 ± 14.4 mmHg (18.0 ± 3.3 to 13.2 ± 1.9 kPa), occurred at 60 min. Blood pressure remained significantly lower than the pre‐injection value for 4 h. There was no change in heart rate. Verbal analogue pain scores, on a scale 0–10, decreased from a median of 7.6 before clonidine to 5.0 after 30 min (P<0.05). The median score at 60 min was 4.3. Thereafter, pain scores were not significantly different from the control score. We conclude that epidural clonidine 150 μg produces only moderate and short‐lived postoperative analgesia. Absorption of clonidine from the epidural space into the blood is very rapid and may contribute to the hypotension that occurs.
Spinal sufentanil in rats: Part III: Effect of diluent volume on epidural sufentanil
Authors: Vercauteren M. , Meert T. , D'Hooghe R. , Boersma F. , Melis W.
Published: January 2009

Male Wistar rats were injected epidurally with various doses of sufentanil in 3 different dilution volumes, in order to determine differences in the lowest ED50 values for analgesia and side‐effects. The lowest ED50 for both a TWR latency > 6 and ≥ 10 s was significantly lower in the 20‐μl group as compared to the 2‐μl group. With an injection of μl, intermediate values were obtained. With regard to the side‐effects, there was a trend towards increased systemic resorption with larger diluent volumes in spite of a better and more selective spinal effect, as evidenced by increasing specificity ratios. In terms of duration of analgesia at fixed doses of sufentanil, different results were obtained. At low doses of sufentanil, a pronounced diluent volume effect was present and the duration of analgesia increased as a function of the volume. At higher doses of sufentanil, however, the volume effect faded away and no differences were observed as a function of the diluent.
Influence of positive end‐expiratory pressure on extravascular lung water during the formation of experimental hydrostatic pulmonary oedema
Authors: Wickerts C.‐J. , Berg B. , Blomqvist H.
Published: January 2009

The influence of positive end‐expiratory pressure (PEEP) on extravascular lung water measured with the double‐indicator dilution technique (EVLWi) has been studied during formation of hydrostatic pulmonary oedema in a canine model. The oedema was created by elevating the mean pulmonary artery pressure (PAP) to 30 mmHg (4.0 kPa) by inflation of a left atrial balloon, and a simultaneous intravenous saline infusion of 15 ml˙kg‐1˙h‐1. All dogs were ventilated with zero end‐expiratory pressure (ZEEP) until the initial EVLWi had increased by 50%. In one group (n = 5) a PEEP of 10 cmH2O (1.0 kPa) was applied and the dogs were studied for a further 4 h and in the other group (n = 5) ZEEP was maintained throughout the study. During the first 2 h after ZEEP/PEEP application EVLWi increased from 13.7 ± 2.1 to 20.2 ± 1.2 ml±kg‐1 with ZEEP ventilation and from 13.6 ± 1.2 to 18.6 ± 1.9 ml±kg‐1 with PEEP ventilation. EVLWi remained unchanged during the last 2 h in both groups. The gas exchange improved with PEEP, arterial oxygen tension increased from 30.4 ± 8.9 kPa to 38.6 ± 2.5 kPa (P<0.01), and the shunt fraction decreased from 6.0 ± 3.8% to 1.2 ± 0.8% (P<0.001). There were significant differences (P<0.01) in both Pao2 and shunt fraction between the ZEEP and PEEP groups throughout the study. In conclusion, positive end‐expiratory pressure improves gas exchange but does not protect against increasing extravascular lung water during the creation of hydrostatic pulmonary oedema.
Application of sublingual buprenorphine in combination with naproxen or paracetamol for post‐operative pain relief in cholecystectomy patients in a double‐blind study
Authors: Witjes W. P. J. , Crul B. J. P. , Vollaard E. J. , Joosten H. J. M. , Egmond J. v.
Published: January 2009

In a double‐blind, placebo‐controlled study in 125 patients undergoing a cholecystectomy, a comparison was made of the quality of post‐operative pain relief during ‘patient‐controlled’ intake of sublingual buprenorphine in combination with either rectally administered naproxen 1000 mg/24 h, paracetamol 4000 mg/24 h or a placebo. Results obtained in 97 patients were analysed. Five of these patients needed a rescue medication with morphine hydrochloride intramuscularly because of insufficient pain relief or because of nausea and vomiting. The quality of pain relief, as measured on a four‐point scale, was comparable in all three groups throughout the study period and no significant differences became apparent. Only on the day of surgery (day 0) was intake of buprenorphine significantly greater in the placebo group (2.3 tablets/24 h) than in the naproxen and paracetamol groups (1.8 and 1.5 tablets/24 h, respectively). It is concluded that after cholecystectomy ‘patient‐controlled’ intake of sublingual buprenorphine as a sole agent provides acceptable pain relief in about 80% of patients. More elaborate methods, such as intravenous patient‐controlled analgesia, might be necessary to achieve good pain relief in the remainder of these patients.
EDTA‐dependent pseudothrombocytopenia in a preoperative patient
Authors: Prestaña D. , Marcote C. , de Castro M. F.
Published: January 2009

We report the case of a patient with a low platelet count preoperatively, but without clinical signs of thrombocytopenia, secondary to EDTA platelet clumping.
Characteristics of muscle nerve sympathetic activity during general anaesthesia in humans
Authors: Sellgren J. , Pontén J. , Wallin B. G.
Published: January 2009

General anaesthesia influences the cardiovascular system at different levels. To increase our knowledge of how sympathetic outflow is affected by anaesthetic interventions, we used direct microelectrode recordings of muscle sympathetic activity (MSA) in the peroneal nerve in 18 patients scheduled for ENT‐surgery. During induction of anaesthesia (propofol 2.1 mg/kg or methohexitone 1.4 mg/kg), all patients showed reductions in MSA (from 41± 4 to 20 ± 4 bursts/min). With endotracheal intubation there was a sudden increase of activity and in several patients the normal pulse‐synchrony of MSA was lost temporarily. Maintenance of anaesthesia with nitrous oxide (n = 12) increased MSA and methohexitone (n = 2), propofol (n = 3) and isoflurane (n = 8) decreased MSA, while the effect of halothane (n = 3) varied. Baroreflex mechanisms were still operative but seemed to be depressed in relation to anaesthetic agent and depth. Laryngeal and surgical stimuli caused increases in MSA and blood pressure, lasting several minutes after the stimulation. It is concluded that the strength of MSA is profoundly influenced by the choice of anaesthetic agent. A suppression of activity is more common than an increase. Qualitatively, several sympathetic reflexes operate in a similar way during light anaesthesia as in awake subjects, but are depressed or absent during deep anaesthesia.
The effect of isoflurane on excitatory synaptic transmission in the rat hippocampus
Authors: Berg‐Johnsen J. , Langmoen I. A.
Published: January 2009

The purpose of this investigation was to study the effect of isoflurane on excitatory synaptic transmission. Rat hippocampal slices maintainedin vitrowere used as a model. Isoflurane caused a dose‐dependent reduction of the excitatory postsynaptic potential (EPSP); 1.5% isoflurane reduced the EPSP by 35 ± 9% (mean ± s.d.) and 3% by 57 ± 11%. Neither spontaneous nor potassium‐stimulated efflux of the glutamate analogue D‐(3H) aspartate was changed, but the content of D‐(3H) aspartate in slices loaded during isoflurane was reduced to 83 ± 12% of control (P<0.05). The intracellularly recorded response to direct application of glutamate increased by 37 ± 20% during isoflurane (3%) and 50 ± 5% during halothane (2%). Isoflurane (3%) enhanced the response to the glutamate receptor agonist quisqualate by 44 ± 19%, whereas the N‐methyl‐D‐aspartate response was unchanged. Isoflurane enhanced the tetanic depression of the population spike. The present results suggest that isoflurane reduces excitatory synaptic transmission by a presynaptic mechanism.
Effect of thoracic epidural etidocaine 1.5% on somatosensory evoked potentials, cortisol and glucose during cholecystectomy
Authors: Dahl J. B. , Rosenberg J. , Kehlet H.
Published: January 2009

The effect of thoracic (T7–8) epidural etidocaine 1.5%, 9 ml, and continuous per‐ and postoperative epidural infusion of etidocaine 1.5%, 4 ml/h, on early (?<500 ms) somatosensory evoked potentials (SEPs), and cortisol and glucose in plasma during cholecystectomy, was examined in ten patients. Spread of analgesia (pin‐prick) was T3 (T1–T3) to L2 (T11–L3) 35 min after injection of etidocaine, and T3 (T2–T4) to T12 (T8–L4) 3 h after surgical incision (median (range)). Before operation, epidural etidocaine had no significant effects on peak‐to‐peak amplitude of SEPs to electrical stimulation at the L1 T10 or T6 dermatomal level (P>0.09). SEPs were abolished in only two patients at T6, and no patient had SEPs abolished at T10 or L1. The plasma concentrations of cortisol and glucose were significantly increased 20 min after surgical incision and remained increased throughout the study. No correlation was found between the block‐induced decrease in the peak‐to‐peak amplitude at T6 or T10 and increase in plasma cortisol, except for a negative correlation at T10 and the initial increase in cortisol (Rs = 0.72, P = 0.03). In conclusion, thoracic epidural administration of 9 ml of etidocaine 1.5% does not provide total afferent somatic blockade assessed by SEP and the stress response to cholecystectomy.
Epinephrine as an adjuvant to amino‐amide local anesthetics does not prolong their duration of action in infraorbital nerve block in the rat
Authors: Renck H. , Hassan H. G.
Published: January 2009

The effects of epinephrine as an adjuvant to local anesthetics were studied in the rat infraorbital nerve block (IONB) model, using solutions of 0.5% prilocaine, 0.5% mepivacaine, 0.125% bupivacaine or 0.125% ropivacaine in 50 mmol/l tris‐hydroxymethylaminomethane (THAM) tested both without and with epinephrine (EPI) added at 2, 4, 8 or 16 μg/ml. Solutions of THAM and EPI in normal saline did not induce IONB. THAM‐buffered solutions of bupivacaine induced IONB of longer duration than bicarbonate‐buffered solutions. Intensity of block during onset was increased only when EPI at 2 and 16 μg/ml was included in bupivacaine solutions. The duration of block induced by prilocaine, bupivacaine and ropivacaine was not significantly prolonged by addition of EPI at any of the concentrations tested. Only at a concentration of 16 μg/ml did EPI significantly prolong the duration of mepivacaine‐induced block (+ 48%). Low concentrations of EPI in solutions of bupivacaine and ropivacaine significantly reduced their duration of action by up to 22% and 57%, respectively. It is concluded that the duration of action of local anesthetics in buffered solutions is only moderately affected by the inclusion of EPI, the effects differing only slightly from one to another. The efficacy of EPI as an adjuvant would seem to be governed by factors affecting the local disposition of the main drugs, such as non‐specific binding, buffering of solutions and tissue pH.
The effects of brain temperature on temporary global ischaemia in rat brain. A 31‐phosphorous NMR spectroscopy study
Authors: Haraldseth O. , Grønås T. , Southon T. , Thommessen L. , Borchgrevink G. , Jynge P. , Gisvold S. E. , Unsgård G.
Published: January 2009

31‐Phosporous magnetic resonance spectroscopy was used in a rat model of 10 min severe incomplete forebrain ischaemia (2‐vessel occlusion with hypotension) to assess the effect of mild brain hypo‐ and hyperthermia (± 2°C) on intracellular pH and high energy phosphates. In three experimental groups intracerebral temperature was maintained at levels of 34, 36 and 38°C during ischaemia and early reperfusion. The steady level of intracellular pH during ischaemia was 6.63, 6.58 and 6.53 in the 34, 36, and 38°C groups, respectively. The rate of initial recovery of intracellular pH in reperfusion was 0.046 ±0.012 pH units per min (± s.d.) in the 36°C group compared to 0.056 ±0.010 (± s.d., P<0.05) in the 34°C group and 0.032 ± 0.009 (± s.d., P<0.01) in the 38°C group. The recovery in early reperfusion of phosphocreatine and ATP was slower in the 38°C group compared to the other groups. The findings were consistent with recent studies, suggesting that even mild hypothermia may afford protection to the ischaemic brain, and furthermore indicate that mild hyperthermia as fever or even subfebrility may be deleterious for the outcome in stroke patients.
Adenosine modulates vascular resistance and fluid filtration in isolated rat lungs
Authors: Jolin Å. , Helset E. , Tollåli T. , Bjertnæs L. J.
Published: January 2009

In adult respiratory distress syndrome, a major concern is to reduce increments in pulmonary vascular resistance (PVR) and maintain the patency of lung microvessels. We have investigated the effects of adenosine, a potent systemic vasodilator, on PVR and fluid filtration rate (FFR) in isolated blood‐perfused rat lungs. The preparations were undamaged or subjected to fat emulsion‐induced injury simulating ARDS. In undamaged lungs adenosine caused a significant dose‐dependent reduction of hypoxia‐induced increases in PVR. Furthermore, the increase in FFR upon elevation of left atrial pressure by 0.77 kPa was significantly hampered by adenosine, 24 nmol ˙ ml‐1˙ min‐1. Employing the same rate of infusion, adenosine, in a group of injured preparations, significantly reduced the rise in PVR towards baseline and completely abolished the further increase upon a superimposed injection of serotonin. In another series of preparations with lung injury randomly assigned to an adenosine group and a control group, adenosine significantly reduced FFR. Thus, adenosine, even when infused at low rates, reduced increments in PVR and fluid filtration, both in undamaged and in fat emulsion‐injured isolated lungs.
Alfentanil combined with vecuronium or pancuronium: haemodynamic implications
Authors: OIKKONEN M.
Published: January 2009

Forty‐two fit, anticholinergized patients, induced with thiopentone, received either vecuronium (V) or pancuronium (P) 0.1 mg/kg, followed by alfentanil 15 μg/kg. The mean heart rate in the Group V was significantly lower than that in the Group P. The difference, 10–15 bpm, appeared after alfentanil administration, and lasted for 5 min postintubation, when under N2O anaesthesia. The Group P patients maintained their arterial pressure closer to the preinduction level than did the Group V patients, but a statistically significant inter‐group difference appeared only at two recording stages. Four Group V patients, contrasted to none of the Group P patients (P<0.05), were put in head‐down tilt, or were given atropine, and/or etilephrine for an undue decrease in arterial pressure. Compared to vecuronium, pancuronium increased heart rate, and protected from arterial hypotension, when combined with low‐dose alfentanil.
Failure of hypertonic saline to resuscitate intestinal ischemia shock in the rat
Authors: Haglind E. , Haljamäe H.
Published: January 2009

The effects of resuscitation with hypertonic saline (HS), administered as a bolus injection or infusion, were studied in a model of intestinal ischemia shock in rats. The model is characterized by severe intestinal mucosal lesions, release of cardioinhibitory substances and endogenous opioid peptides, and it results in high mortality rates. The blood pressure improved after HS given as an infusion for 1 h. The effects on blood pressure of HS given as a bolus and of normotonic saline (NS) were not significant. Plasma volume was not different from unshocked control animals in either HS infusion or NS infusion groups 2 and 4 h after infusion. Liver metabolic consequences of intestinal shock did not differ comparing the HS and NS groups, and the same result was found concerning the mucosal lesions in the small intestine. The 7‐day survival decreased in the HS infusion group (14%) compared to untreated shock (46%) or NS infusion (54%) groups. We conclude that HS failed to resuscitate intestinal ischemia shock. These experiments indicate that HS treatment could even, in contrast to previous reports on hemorrhagic shock, be disadvantageous or dangerous in shock states characterized by extensive tissue injury.
A porcine model for sequential assessments of cerebral haemodynamics and metabolism
Authors: Åkeson J. , Nilsson F. , Ryding E. , Messeter K.
Published: January 2009

We present a physiologically stable porcine model designed for sequential assessments of pharmacological effects on mean hemispheric cerebral blood flow (CBF) and cerebral metabolic rate for oxygen (CMRo2) at sustained normocapnia. The dynamic influence of continuously administered fentanyl (0.040 mg ˙ kg‐1 ˙ h‐1 i.v.), nitrous oxide (70%) and pancuronium (0.30 mg ˙ kg‐1 ˙ h‐1 i.v.) on these variables was studied in eight normoventilated pigs. CBF was reliably assessable at 10‐min intervals by clearance of intra‐arterially injected 133Xe, monitored by an extracranial scintillation detector. CMRo2 was calculated from CBF and the simultaneously measured cerebral arteriovenous difference in blood oxygen content. The intracerebral distribution of a contrast medium injected into the external and internal carotid arteries was studied by angiography, and the cerebral venous outflow was investigated by measurements of the distribution of an intra‐arterially administered non‐diffusible tracer, [99mTc]pertechnetate, to the internal and external jugular veins. After a 3‐h equilibration period, CBF and CMRo2 were determined on six occasions over a study period lasting 1 h 40 min. The mean ranges of these variables were 56–60 and 1.9–2.0 ml ˙ 100 g‐1 ˙ min‐1, respectively. We conclude that the model enables repeated assessments of CBF and CMRo2 under stable physiological background conditions and thus valid cerebral pharmacodynamic investigations of drugs given for anaesthesia.
Gas exchange as monitored in mixed venous and arterial blood during experimental cardiopulmonary resuscitation
Authors: Wiklund L. , Jorfeldt L. , Stjernström H. , Rubertsson S.
Published: January 2009

Nineteen anaesthetized piglets were investigated. After catheterization and a stabilization period, ventricular fibrillation was induced with a transthoracic DC shock, after which a 10‐min period of cardiopulmonary resuscitation (CPR) took place. CPR included manual chest compression and mechanical ventilation with pure oxygen. After 1 min of CPR, an infusion of alkaline buffer was begun and completed within 5 min. A total of 50 mmol of either sodium bicarbonate (n = 6) or tris buffer mixture (n = 7) were given. These two groups were compared with a third control group (n = 6) receiving the same volume of normal saline. After 8 min of CPR all animals were given 0.5 mg adrenaline i.v., and after 10 min DC shocks were used to revert the heart back to normal sinus rhythm. Our results demonstrate that blood flow and not ventilation is the limiting factor for the efficient disposal of CO2 during CPR. This also applied when the demand for CO2 transport was increased by administration of sodium bicarbonate. The respiratory exchange ratio increased 1.9‐fold, indicating that the transport of carbon dioxide was less affected than that of oxygen. The estimated alveolo‐arterial oxygen tension difference, shunt, and overall ventilation/perfusion ratio increased, creating an inverse hyperbolic relationship between arterial Pco2 and Po2. The difference between mixed venous and arterial Pco2 correlated well to the mixed venous Pco2, implying more efficient pulmonary elimination of Pco2 when the mixed venous Pco2 was high. Pulmonary gas exchange during CPR appears to be independent of alkaline buffer therapy in the form of sodium bicarbonate or tris buffer mixture. We conclude that experimental closed chest CPR seems to be accompanied by a change in the V'A/Q' relationship in the lungs with simultaneously increased dead space and shunt.
Influence of intrathecal morphine and naloxone intervention on postoperative ventilatory regulation in elderly patients
Authors: Johnson A. , Bengtsson M. , Söderlind K. , Löfström J. B.
Published: January 2009

Thirty elderly patients undergoing major hip surgery under spinal analgesia were randomly allocated in a double‐blind manner into three groups. The aim was to evaluate the influence of intrathecal morphine and postoperative naloxone infusion on the regulation of ventilation. The Bupivacaine Group received spinal analgesia with 20 mg bupivacaine intrathecally. The Morphine Group received spinal analgesia with 20 mg bupivacaine + 0.3 mg morphine intrathecally. The Naloxone Group received spinal analgesia with 20 mg bupivacaine + 0.3 mg morphine intrathecally + postoperative naloxone infusion intravenously (1 μg/kg/h over 12 h, 0.25 μg/kg/h over the next 12 h). Evaluation of resting ventilation and the ventilatory responses to hypercarbia and hypoxaemia was made on three occasions: before surgery, and 8, and 24 h after the intrathecal injection. Intrathecal morphine had no significant effect on ventilatory regulation in elderly patients undergoing major hip surgery performed under bupivacaine spinal analgesia. Postoperative administration of opioids or sedatives after intrathecal morphine as well as postoperative blood loss associated with a fall in blood pressure appeared to increase the risk of developing respiratory depression. Naloxone infusion seemed to reduce the risk of developing respiratory depression. Furthermore, one third of the elderly had a poor response to hypoxaemia before surgery.
Do anticholinergic agents affect the occurrence of postanaesthetic nausea?
Authors: Salmenperä M. , Kuoppamäki R. , Salmenperaä A.
Published: January 2009

In order to establish if anticholinergic drugs might influence postoperative nausea and vomiting, 100 ASA I‐II adult patients scheduled for minor orthopaedic procedures, varicose vein stripping or inguinal herniorraphy were randomised to receive, in a double‐blind fashion, either a premedicant and a reversal dose of 0.003 and 0.0075 mg/kg of glycopyrrolate or 0.006 and 0.015 mg/kg of atropine, respectively. Nitrous oxide, after thiopentone induction was used for anaesthesia with fentanyl and diazepam as supplements and pancuronium for relaxation. In the recovery room, up to 2 h after surgery, 28% of the patients in the glycopyrrolate group and 8% in the atropine group experienced nausea (P=0.017). Thereafter, the patients complained of nausea at decreased and equal frequencies in both groups. The incidence of vomiting was not statistically significantly different. Droperidol was needed, to control persistent emesis, three times more often in the glycopyrrolate than in the atropine group. It is concluded that substitution of glycopyrrolate for atropine increases the likelihood of postoperative nausea, and continued use of atropine should be considered in patients at risk of postoperative emesis.
The accuracy of pulse oximetry at two haematocrit levels
Authors: Vegfors M. , Lindberg L. G. , Öberg P. Å. , Lennmarken C.
Published: January 2009

The object of this study was to investigate the influence of haematocrit on the accuracy of pulse oximetry. Seven Swedish land race rabbits were studied. The oxygen saturation of haemoglobin was decreased stepwise using increasing fractions of nitrogen to the inspiratory gas. One pulse oximeter probe was attached on the front leg and another probe directly over the common carotid artery. The pulse oximeter readings (Spo2) were compared with simultaneous oxygen saturation analysis (Sao2) by a haemoximeter. The pulse oximeter measurements were performed at the haematocrit levels of approximately 40% and 11%, respectively. We found a good correlation between Spo2and Sao2in a wide range of the oxygen saturation, i.e. Sao226–100%. After haemodilution the correlation was improved in the range 86–100%, but not in the range 26–85%. No correlation between Spo2and Sao2was found when the sensor was attached directly over the artery during normal haematocrit levels. After haemodilution a better correlation was however obtained. These results indicate that the accuracy of pulse oximetry is dependent on the haematocrit level.
Intubating conditions and onset of neuromuscular block of rocuronium (Org 9426); a comparison with suxamethonium
Authors: Huizinga A. C. T. , Vandenbrom R. H. G. , Wierda J. M. K. H. , Hommes F. D. M. , Hennis P. J.
Published: January 2009

The intubating conditions and neuromuscular blocking profile following 600 μg ˙ kg‐1 rocuronium (Org 9426) have been investigated in patients under various experimental conditions. They were compared with conditions following 1.5 mg ˙ kg‐1 suxamethonium, preceded by a precurarising dose (10 mg) of gallamine, and with those in a control group in the absence of a muscle relaxant. Rocuronium produced good to excellent intubating conditions at 60 as well as at 90 s after administration, even though there was only a partial blockade of the adductor pollicis muscle. Intubating conditions following suxamethonium were comparable with those after rocuronium. Half of the control patients could not be intubated. The clinical duration and the recovery time of 600 μg ˙ kg‐1 of rocuronium were 24(4) and 9(3) min (mean(s.d.)), respectively. Rocuronium may have a major advantage over existing non‐depolarising muscle relaxants due to the early presence of excellent intubating conditions. The results indicate that rocuronium may replace suxamethonium in procedures in which rapid sequence induction is required.
Reaction time in cancer patients receiving peripherally acting analgesics alone or in combination with opioids
Authors: Banning A. , Sjøgren P. , Kaiser F.
Published: January 2009

Continuous Reaction Time (CRT) was measured in cancer patients receiving peripherally acting analgesics either alone (n = 16) or in combination with opioids (n = 16). Comparison was performed matching the patients from each group for age and performance status. Statistically significant prolongations of CRT and higher sedation scores were seen in the opioid group, while performance status did not have any influence on CRT.
Ketamine anaesthesia in a patient with septic shock
Authors: Yli‐Hankala A. , Kirvelä M. , Randell T. , Lindgren L.
Published: January 2009

A 71‐year‐old male patient was operated on in a septic state (tachycardia, hypotonia, fever peaks, disorientation) because of an occluding tumour of the biliary tract. Ketamine was used as the main anaesthetic. Mean arterial pressure increased markedly and diuresis started during the anaesthesia. The inotropic support (dopamine, dobutamine, noradrenaline) could be reduced. Ketamine anaesthesia seemed to have a beneficial haemodynamic effect in septic shock.
Effect of a non‐steroidal anti‐inflammatory drug, diclofenac, on haemostasis in patients undergoing total hip replacement
Authors: Laitinen J. , Nuutinen L. S. , Puranen J. , Ranta P. , Salomäki T.
Published: January 2009

Haemostasis was studied in patients receiving diclofenac for postoperative pain relief. Intravenous diclofenac 75 mg over 60 min, followed first by an infusion of 5 mg/h for 15 h and then by 50 mg every 8 h orally was administered to 20 patients undergoing total hip replacement. Eighteen patients receiving a placebo infusion and dextropropoxyfen per os served as controls. The results showed no statistically significant differences between the groups in blood loss, bleeding time (IVY), partial activated thromboplastin time and prothrombin complex assay or in platelet count. The measurements were performed preoperatively, 3 h postoperatively and on the fourth and tenth postoperative days. Plasma concentrations were also determined in ten patients undergoing knee arthroscopy. An i.v. diclofenac infusion of 75 mg over a period of 15 min was administered either once (to half of the patients) or twice. The mean diclofenac concentrations were 28 ± 5 nmol/ml (± s.d.) after 15 min and 36 ± 12 nmol/ml after the second infusion. The bleeding time in the arthroscopy patients receiving one or two bolus infusions of 75 mg diclofenac remained at the control level. It is concluded that diclofenac given as an intravenous infusion of 75 mg in 60 min, then 5 mg/h for 15 h, followed by 50 mg every 8 h orally, is as safe as dextropropoxyfen for pain relief in patients undergoing major orthopaedic surgery as far as coagulation data are concerned.
Interscalene plexus block for arthroscopy of the hurnero‐scapular joint
Authors: SANDIN R. , STAM H. , STERNLO J‐E.
Published: January 2009

Interscalene plexus block was performed in nine patients subjected to shoulder arthroscopy. The operating conditions, including muscle relaxation, were fully adequate in all patients (after additional local anaesthesia of the skin in four patients). With the exception of one patient who experienced temporary hoarseness(probably due to a concomitant block of the recurrent laryngeal nerve), no side effects were found and the patients tolerated the surgical procedure well. Interscalene block might be a suitable alternative to general anaesthesia for shoulder arthroscopy. However, additional local anaesthesia at thesite where the arthroscope is to be inserted is frequently required.
Low molecular weight heparin for thromboprophylaxis and epidural/spinal anaesthesia – is there a risk?
Authors: Bergqvist D. , Lindblad B. , Mätzsch T.
Published: January 2009

This article reviews the problem of bleeding in connection with epidural/spinal anaesthesia, with special emphasis on the use of low molecular weight heparins for thromboprophylaxis. There are methodological difficulties to studying the problem in a scientifically correct way because of the rarity of the complication. However, from the data in the literature there are no indications of an increased risk in using the combination of low molecular weight heparin in prophylactic doses and epidural/spinal anaesthesia. So far, there is only a single case report, of spinal haematoma, although low molecular weight heparins have been used in combination with epidural/spinal anaesthesia in at least 1000000 patients. In controlled studies, at least 10000 patients have been given the combination without complications.