bluuebunny/crossref_metadata_2025 huggingface dataset:
The Combined Effects of Pregnancy and Repeated Plasma Exchange on Serum Cholinesterase Activity
Authors: Evans. R. T. , Robinson A.
Published: January 2009

Fourteen patients are described in whom repeated plasma exchange was performed as part of their treatment for Rh alloimmunisation during pregnancy. Despite administration of fresh frozen plasma at frequent intervals during therapy, serum cholinesterase activity was shown to be reduced to levels sufficient to put many of them at risk from suxamethonium sensitivity. It is recommended that if short‐acting muscle relaxants are intended to be used during the delivery of such patients, a careful investigation of cholinesterase status should be undertaken beforehand.
Catecholamine and Endocrine Response in Children During Halothane and Enflurane Anaesthesia for Adenoidectomy
Authors: Sigurdsson G. H. , Lindahl S. G. E. , Nordén N. E.
Published: January 2009

In 28 children undergoing adenoidectomy, plasma concentrations of catecholamines, ACTH and Cortisol were measured. Fourteen children were anaesthetized with halothane (seven non‐intubated, seven intubated) and 14 with enflurane (seven non‐intubated, seven intubated). During undisturbed anaesthesia, plasma catecholamines were significantly higher with halothane than with enflurane (P<0.05). Immediately after surgery, catecholamines were increased up to 300% in the halothane groups. In the enflurane groups, however, the catecholamine concentrations remained unchanged. This difference between the two agents, after surgery, was statistically significant (P<0.01 for intubated and P<0.001 for non‐intubated children). Fifteen minutes postoperatively no difference was found in plasma concentrations between the groups. In all four groups, plasma concentrations of ACTH and Cortisol increased similarly during the procedure. It was concluded that plasma catecholamines were higher during halothane than during enflurane anaesthesia in children undergoing adenoidectomy. This difference may be caused by a stimulating effect of halothane on the endogenous catecholamine release. This increased sympathomimetic response during halothane anaesthesia was correlated to the incidence of ventricular arrhythmias previously found with this agent during adenoidectomy.
Metabolic Correlates in Infants and Children During Anaesthesia and Surgery
Authors: LindahiM.D. S. G. E. , Hulse M. G. , Hatch D. J.
Published: January 2009

In 58 infants and children with body weights between 2.8 and 20.5 kg carbon dioxide production (V.co2 ml min‐1) was measured during halothane anaesthesia for minor surgical procedures. In 22 cases measurements were made during both spontaneous and controlled ventilation during the same operation. A non‐rebreathing circuit was used. Expired ventilation volume was measured with a dry gas meter and expired gas collected during 3–5 min in a Douglas bag. The carbon dioxide fraction of exhaled gas was determined with a sampling Gould capnograph. A respiratory quotient (RQ) of 0.8 was used to calculate oxygen consumption (V.o2 ml min1). During spontaneous breathing, regression analysis of the relationship between V.co2 and kg and between V.o2 and kg showed high intercepts while corresponding relations to kg revealed an almost direct proportionality. Thus, V.co2 and V.o2 ought to be related to body weight in kg in spontaneously breathing children. The mean value (±1 s.d.)for V.co2 was 11.4 ±3.1 ml kg‐3/4 and for V.o2 14.2 ±3.9 ml kg‐3/4. During controlled ventilation, the relationship between kg b. w. showed for V.co2 as well as for V.o2 an almost direct proportionality with a mean value (± 1 s.d.) for V.co2 of 6.3± 1.6 ml min 1 kg‐1 and for V.o2 of 7.8±2.0 ml min kg. Prediction of V.o2 for infants and children of this size could be based upon 14Xkg during halothane anaesthesia and surgery.
Mucus Transport and Surface Damage After Endotracheal Intubation and Tracheostomy. An Experimental Study in Pigs
Authors: Alexopoulos C. , Jansson B. , Lindholm C‐E.
Published: January 2009

The effects on mucus transport of different grades of tracheal injury produced experimentally by an intubation tube were studied in 26 pigs. Two of them were not intubated and served as controls, while the rest were anaesthetized and either intubated or tracheostomized, or both, and ventilated for approximately 4.5 h. They were then killed and the trachea and larynx were immediately removed and placed in a specially designed chamber at 3 7oG and 85 % relative humidity. Cardio‐green dye was deposited caudally in the trachea as a mucus marker. The mucus transport was observed macroscopically and the ultrastructure of the tracheal wall at the region of mucus arrest was studied by light microscopy and scanning and transmission electron microscopy. In non‐intubated pigs the mucus was transported to the posterior larynx. The ciliated epithelium was usually intact along the pathway where cardio‐green‐stained mucus had travelled. In pigs which had been intubated and/or tracheostomized, mucus transport stopped completely at different levels of the trachea. The damage to the ciliated epithelium varied; in some animals there was almost none at all and in others there was a patchy loss of a large proportion of the cilia, or complete lack of cilia. Lesions which also included epithelial cells were often seen. Tracheal injury due either to a cuffed endotracheal tube or to a tracheostomy tube, with destruction of epithelium and cilia, causes a barrier to mucus transport, leading to arrest and accumulation of mucus further down in the airway. We were unable, however, to demonstrate a direct correlation between grade of damage and tendency to mucus arrest.
Cyclic Nucleotides in Rat Brain During Lidocaine Infusion
Authors: Yamada K. , Maekawa T. , Okuda Y. , Takeshita H.
Published: January 2009

The concentrations of cyclic 3′, 5′‐guanosine monophosphate (cGMP) and cyclic 3′, 5′‐adenosine monophosphate (cAMP) in the cerebellar and cerebral cortex were measured during lidocaine infusion and during bicuculline‐induced seizures in rats. The rats were divided into three groups: control, lidocaine (0.74 mg/min) and bicuculline (1.2 mg/kg). The lidocaine group was divided into four stages according to the EEG pattern; desynchronized, synchronized, seizure and recovery. At the desynchronized and synchronized stages, cGMP and cAMP concentrations in both cerebellar and cerebral cortex remained unchanged except for a modest decrease in cerebral cGMP at the desynchronized stage. At the seizure stage, cerebellar cGMP increased from 5.2±0.9 to 9.2±1.4 pmol/mg protein and cerebellar cAMP decreased from 8.9 ± 0.6 to 6.9±0.6 pmol/mg protein. These changes in concentrations at the seizure stage returned to the control at the recovery stage. During bicuculline‐induced seizures, cGMP and cAMP concentrations increased strikingly in both cerebellar and cerebral cortex. These results indicated that Hcfocaine‐induced seizures were accompanied by significant changes in cerebellar cyclic nucleotide concentrations in rats.
Perivascular Axillary Block III: Blockade Following 40 ml of 0.5%, 1% or 1.5% Mepivacaine with Adrenaline
Authors: Vester‐Andersen T. , Eriksen C. , Christiansen C.
Published: January 2009

Perivascular axillary blockade was performed on 90 patients with the aid of a catheter technique. All blockades were performed by the same anaesthetist, who practised perivascular axillary blockade three or four times a day. The patients were randomly allocated to three groups. The injected volume of local anaesthetic was constant in each group: 40 ml mepivacaine with adrenaline. The concentration and, consequently, the amount (mg) were variable factors: ½% (200 mg), 1% (400 mg) and 1½% (600 mg). Sensory and motor blockade were tested 30 min after each injection. All three groups showed a high incidence of analgesia (70%‐100%) in all cutaneous segments, and none of the blockades showed total failure of the sensory blockade. The lowest incidence of sensory blockade was found in the areas innervated by the axillary, the radial and the musculocutaneous nerves, but no difference was found between the groups. However, the motor blockade was found to improve with increasing concentration of local anaesthetic solution.
Perivascular Axillary Block IV: Blockade Following 40, 50 or 60 ml of Mepivacaine 1 % with Adrenaline
Authors: Vester‐Andersen T. , Husum B. , Lindeburg T. , Borrits L. , Gøthgen I.
Published: January 2009

Perivascular axillary blockade was performed on 90 patients with the aid of a catheter technique. The patients were randomly allocated to receive either 40, 50 or 60 ml of 1 % mepivacaine with adrenaline 1:200,000. Blood concentrations of mepivacaine were measured up to 90 min after injection in seven, eight and ten of the patients from the three groups. Sensory and motor blockade was evaluated 20, 30 and 40 min after injection. All groups showed the same temporal development of the blockade, i.e. improval of the blockade during the period from 20 to 40 min after injection, but no difference was found in the sensory or motor blockade between the three groups. However, a further analysis of the incomplete blockades showed a better quality of the sensory blockade in the groups given 50 and 60 ml than in the group given 40 ml. None of the 90 patients showed any signs of systemic toxic reactions. The mean peak values of blood concentrations were 0.5‐1.0 μg/ml higher in the groups A given 50 ml and 60 ml than in the group given 40 ml. On the basis of the present and two previous investigations on the dose response in perivascular axillary blockade, a dose of 50 ml 1% mepivacaine with adrenaline or I r another equivalent drug with vasoconstrictor is recommended.
Absence of Signs of Vitamin B12 ‐ Nitrous Oxide Interaction in Operating Theatre Personnel
Authors: Salo M. , Rajamaki A. , Nikoskelainen J.
Published: January 2009

Inactivation of vitamin B12 by nitrous oxide leads to megaloblastic haematopoiesis. Peripheral blood counts and films, serum vitamin B12 and plasma and erythrocyte folate concentrations were studied in eight anaesthetists and seven internists to find if the interaction is an occupational health hazard to operating theatre personnel chronically exposed to trace concentrations of nitrous oxide. In addition, blood counts were studied in two retrospective materials of 118 operating theatre nurses working in scavenged operating theatres and in ten subjects working in unscavenged theatres. No definite signs of B12‐nitrous oxide interaction could be observed in the peripheral blood samples from these persons.
The In Vitro Effect of Hypotensive Agents on the Affinity of Haemoglobin for Oxygen
Authors: Jones R. M. , Pollard B. J. , Rowbottom S. J. , Lovelock H. A. , Borthwick J. M.
Published: January 2009

The effect of nitroglycerine, sodium nitroprusside, trimetaphan, pentolinium, labetalol and propranolol on the affinity of haemoglobin for oxygen was studied in vitro. Only pentolinium had a significant effect, increasing the binding of oxygen by haemoglobin. The significance of these results is discussed.
Pharmacokinetics and Sedative Effect of Midazolam in Connection with Caesarean Section Performed Under Epidural Analgesia
Authors: Kanto J. , Aaltonen L. , Erkkola R. , Äärimaa L.
Published: January 2009

Midazolam, the new investigational 1,4‐benzodiazepine derivative with highly water‐soluble salts, was studied as an anaesthesiological adjuvant in 11 patients undergoing elective caeserean section under epidural analgesia. I.v. administered midazolam, 0.075 mg/kg after delivery, caused a rapid and marked sedative effect, lastingfor about 2–3 h. Short‐lasting anterograde amnesia of about 30 to 60 min was reported as well. The serum levels of the parent drug and its active metabolites were determined in six cases by a radioreceptor assay and pharmacokinetic parameters were calculated on the basis of these levels by a two‐compartment open model. Up to 3 h after midazolam administration, good correlation between the sedative effect and serum drug levels was found. The rapid but short‐lasting action can be explained by the pharmacokinetic parameters of midazolam: a short distribution phase half‐life (4.19 min), and a short elimination phase half‐life (67.85 min) due to a high clearance value (13.18 ml/min/kg) and a moderate distribution volume (1.20 1/kg).
Pollution of Delivery Ward Air by Nitrous Oxide. Effects of Various Modes of Room Ventilation, Excess and Close Scavenging
Authors: Bernow J. , Björdal J. , Wiklund K. E.
Published: January 2009

According to a survey to all Swedish delivery departments, nitrous‐oxide‐oxygen analgesia given on demand is frequently used by women in labour. Excess gas scavenging equipment was lacking in 12 out of a total of 73 delivery wards in September 1982. The effects of various room ventilation and excess gas scavenging methods on the nitrous oxide concentration in the delivery room were investigated. The 8 h time weighted average (TWA) for midwives was 24 ppm nitrous oxide with room ventilation in accordance with the Swedish recommended standard and with excess gas scavenging using 1.61 reservoir tube volume. For women in labour, close scavenging using various modifications of conventional tube systems was shown to be practically impossible to apply. Close scavenging via a specially designed plastic hood surrounding the face of the woman in labour resulted in very low nitrous oxide concentrations in the delivery room, even when the room ventilation was reduced to very low values.
Failure of Epidural Analgesia to Modify Postoperative Depression of Delayed Hypersensitivity
Authors: Hjortsø N.‐C. , Andersen T. , Frøsig F. , Neumann P. , Rogon E. , Kehlet H.
Published: January 2009

Delayed hypersensitivity to four common antigens was assessed in 32 patients undergoing major abdominal surgery randomly allocated to either general anaesthesia (fentanyl + O2/N2O + postoperative pain relief with systemic opiates) or general anaesthesia + epidural analgesia (local anaesthetics + morphine) continued for 72 h. Skin‐test responses were performed 2 days before surgery and 1 day after surgery and compared to a similar retesting schedule in 16 comparable non‐operative control patients. Cumulated mean skin‐test responses increased from 1290 to 2330 mm2 (P<0.0001) during retesting in the non‐operative control group. In contrast, mean skin‐test responses in patients operated during general anaesthesia + systemic opiates for postoperative pain relief fell from 1422 to 1227 mm2 (P=0.3) and in patients receiving epidural analgesia from 1228 to 890 mm2 (P=0.06), without statistically significant differences between these two groups (Pg0.5). Thus, surgery leads to depression of delayed hypersensitivity and this impairment in immunofunction is not modified by an epidural analgesic regimen providing adequate pain relief.
Effects of Thoracic Epidural Analgesia on Cardiovascular Function and Plasma Concentration of Free Fatty Acids and Catecholamines in the Dog
Authors: Hotvedt R. , Platou E. S. , Refsum H.
Published: January 2009

Increased plasma levels of free fatty acids (FFA), leading to increases in the myocardial oxygen demand, are seen after, for example, surgical stress, traumas and myocardial infarction. The present study was undertaken to investigate the cardiovascular effects of thoracic epidural analgesia (TEA) and the effect of TEA on the plasma concentration of FFA and catecholamines. In 10 sodium‐pentobarbital‐anaesthetized dogs the local anaesthetic agent bupivacaine was injected into the thoracic epidural space via a surgically introduced catheter. TEA markedly reduced heart rate, mean aortic blood pressure, left ventricular systolic blood pressure and dP/dtmax. TEA reduced the plasma concentration of FFA. The FFA‐lowering effect was greatest when the FFA values were high. The effect of TEA on the plasma concentration of noradrenaline and adrenaline was inconsistent and seemed to be of minor importance for the haemodynamic and FFA effects of TEA. The study indicates that TEA, by its haemodynamic and FFA‐lowering effects, may reduce myocardial oxygen demand.
Pain Relief with Epidural Buprenorphine After Spinal Fusion: A Comparison with Intramuscular Morphine
Authors: MurphyMB D. F. , MacEvilly M.
Published: January 2009

In a prospective randomized trial, epidural buprenorphine was compared with intramuscular morphine for pain relief after spinal corrective surgery. Both forms of analgesia were given on demand and both produced excellent reduction of pain as assessed with visual linear analogue. The quality and duration of analgesia were similar for both groups of patients. Since the correct placement of epidural catheters could be done intraoperatively in difficult cases and since many patients for spinal corrective surgery have limited respiratory reserve, the authors feel that epidural buprenorphine provides an excellent alternative to conventional opiate analgesia after this type of surgery.
Effect of Epidural Morphine on Post‐operative Pulmonary Dysfunction
Authors: Bonnet F. , Blery CH. , Zatan M. , Simonet O. , Brage D. , Gaudy J.
Published: January 2009

The effect of post‐operative epidural morphine analgesia on pulmonary function was assessed after abdominal surgery and compared to conventional analgesia. In a control group, ten patients received a parenteral analgesic, non‐narcotic drug. In a second group of 11 patients, epidural morphine was injected after the operation and continuous analgesia was prolonged until the 3rd post‐operative day by means of repeated injections through an epidural catheter. Analgesia was tested on a visual pain scale. Pulmonary function was evaluated by measurements of blood gases, pulmonary volumes (vital capacity, by spirometry, and functional residual capacity by helium dilution technique) and forced expiratory volume in one second. Measurements were performed on the day before the operation and on the first, third and sixth post‐operative days. Pain scoring documented a better analgesia in the epidural group during the post‐operative period. By contrast, epidural morphine was unable significantly to improve VC, FEV1 and FRC during the post‐operative course. The results suggest that pain is not an important factor of decreased post‐operative pulmonary function.
Complement Activation and its Relationship to Adult Respiratory Distress Syndrome. An Experimental Study in Pigs
Authors: Borg T. , Gerdin B. , Häijgren R. , Warolin O. , Modig J.
Published: January 2009

Pulmonary leucostasis induced by complement activation has been considered an important pathogenic factor in adult respiratory distress syndrome (ARDS). To determine whether complement activation per se could evoke pulmonary dysfunction similar to ARDS, pigs were repeatedly infused with complement‐activated plasma (CAP). Complement activation was produced by incubation of plasma with zymosan. Three groups of animals were investigated. Control animals received non‐activated plasma. Nine animals (Group II) were given four infusions of GAP at a rate of 7 ml min‐1, and another nine animals (Group III) received two CAP infusions at a rate of 7 ml min‐1 followed by two at a rate of 14 ml min‐1. In the control animals there were no changes in gas exchange or haemodynamic variables and the leucocyte counts gradually increased. Infusion of CAP resulted in transient peripheral leucopenia and a dose‐rate‐dependent reversible increase in pulmonary vascular resistance in all animals. In one animal of Group II and in six of Group III there was a significant infusion‐related decrease in PaO2 due to increased venous admixture. These animals were characterized by an enhanced pulmonary vascular tone before the start of the first CAP infusion. They also displayed a more pronounced pulmonary vascular response to infusion of CAP. The changes in gas exchange variables and pulmonary haemodynamics showed no relation to the degree of leucopenia or decrease in platelet count. The increased venous admixture was caused by “dry” ventilation/perfusion mismatching and not by oedema. These results suggest that additional factors besides complement activation and pulmonary leucostasis are required for the development of increased microvascular permeability and the pulmonary oedema characterizing ARDS.
Fourier Analysis of Effects of Varying Pressure Waveforms in Electrical Lung Analogs
Authors: Bergman N. A.
Published: January 2009

Six voltage waveforms were devised to simulate pressure curves of varying configuration for use in artificial ventilation. These waveforms were subjected to Fourier analysis and terms of the resulting series applied to a simple two‐branch resistive‐capacitive circuit intended to represent a lung analog using computer simulation. Current (analagous to flow) and charge (analogous to volume) in each branch could be graphically displayed. Differences among the waveforms in such attributes as efficiency, inspiratory work, volume introduced per unit of mean pressure applied, and relative volume distribution between the two branches could be demonstrated. All waveforms were capable of delivering a predetermined volume to the circuit with adjustment of their peak pressure (voltage). It was not possible to designate any of the waveforms as “superior” since advantage in one attribute, such as efficiency, was accompanied by deficiencies in other characteristics such as uneven volume distribution. Despite obvious severe limitations on physiological interpretations of such data, Fourier analysis of respiratory waveforms appears to be a useful teaching, illustrative, and exploratory method.
Cardiac Dysrhythmias and Heart Rate Changes at Induction of Anaesthesia: A Comparison of Two Intravenous Anticholinergics
Authors: GreenanMB J.
Published: January 2009

Glycopyrrolate, 0.2 mg, or atropine, 0.6 mg, was administered intravenously together with methohexitone for the induction of anaesthesia in unpremedicated patients. The use of atropine, compared with glycopyrrolate, was associated with a greater rise in heart rate, a greater number of patients whose heart rates doubled, and a higher incidence of dysrhythmias. Glycopyrrolate is recommended for use as an intravenous anticholinergic agent, particularly in patients with cardiovascular impairment.
Platelet Model for Halothane‐Induced Effects on Nucleotide Metabolism Applied to Malignant Hyperthermia
Authors: Solomons C. G. , Masson N. C.
Published: January 2009

A relatively non‐invasive screening technique using venous blood analyzed by high performance liquid chromatography (HPLC) was developed to assess the effects of halothane on platelet nucleotide metabolism. Platelets were selected for study because of their contractile characteristics and many metabolic similarities to voluntary muscle. Platelets of 22 patients who previously had a documented clinical episode of malignant hyperthermia demonstrated a significant change in their nucleotide profile due to halothane exposure compared to normal subjects and 10 patients with musculoskeletal and metabolic disorders. These results showed 100% correlation with the skeletal muscle contracture test for malignant hyperthermia (PHB). The platelet‐halothane bioassay is highly reproducible and specific for detecting malignant hyperthermia with a significant degree of expression at the time of the venipuncture. The assay deserves further study as an aid to the diagnosis of the degree of malignant hyperthermia susceptibility.
Painless Venipuncture. A Clinical Trial of Iontophoresis of Lidocaine for Venipuncture in Blood Donors
Authors: Arvidsson S. B. , Ekroth R. H. , Hansby A. M. C. , Lindholm A. H. , William‐Olsson G.
Published: January 2009

Discomfort or frank pain at venipuncture may be a reason for abstaining from giving blood. In an attempt to offer a painless alternative, a method for iontophoretic application of local anaesthetics was developed. Its effectiveness in producing anaesthesia for venipuncture was tested in a double‐blind trial in 47 blood donors. A positive result was obtained in 89%, as against 28% in the placebo group.
Blood Concentrations of Lidocaine, Mepivacaine and Bupivacaine During Caudal Analgesia in Children
Authors: Takasaki M.
Published: January 2009

The venous blood concentrations of lidocaine, mepivacaine and bupivacaine were measured in children following the caudal epidural administration of these local anaesthetic solutions with adrenaline. The mean maximum concentrations of lidocaine and mepivacaine were 2.20 μg/ml and 2.53 ug/ml, respectively, which occurred at 45 min after injection of lidocaine or mepivacaine 11 mg/kg. By combined administration of 5.5 mg/kg equally of lidocaine and mepivacaine, the blood concentration of mepivacaine was significantly higher than that of lidocaine. The mean maximum concentration of bupivacaine was 0.67 μg/ml and occurred at 45 min after injection of bupivacaine 3.7 mg/kg. The blood concentration of bupivacaine was consistently significantly lower than that of lidocaine or mepivacaine. These results demonstrate that the blood concentrations of the three local anaesthetics following caudal administration are all below the toxic levels in spite of application of the maximum dosage recommended for adults.
Cerebral Energy State and Glycolytic Metabolism During Enflurane Anesthesia in the Rat
Authors: SeoM.D. K. , Maekawa T. , Takeshita H. , Okuda Y.
Published: January 2009

The effects of enflurane anesthesia on the cerebral cortical energy state and glycolytic metabolism were studied in rats. Twenty‐four rats were divided into four groups with increasing concentrations of enflurane in the arterial blood, i.e. control (1,9±0.3 mg/dl, means+s.e.mean), level I (16.1 ±1.1 mg/dl), level II (26.0± 1.6 mg/dl), and level III (32.9±0.9 mg/dl). At level I, high voltage 1–3 Hz slow waves superimposed on low voltage 10–12 Hz waves were predominant, and at levels II and III, spiking activity and burst suppression were recorded in the EEG. The duration of suppression at level III was significantly longer than that at level II. During enflurane anesthesia, there were no significant differences compared with the control group in the cerebral energy state or energy charge. Glycolytic metabolism remained unchanged except for an increase in glucose at levels II and III. Effects of hypocapnia and hypercapnia were examined in an additional 12 rats with an enflurane concentration in the blood similar to that al level II. Irrespective of PacOz levels, there were no significant changes in cerebral energy charge and glycolytic metabolites except for a decrease in glucose and an increase in lactate at hypocapnia. It was concluded that there was neither evidence of derangement of energy state nor increased anaerobic metabolism in the cerebral cortex during enflurane anesthesia.
Hyperpotassemia During Massive Blood Transfusions
Authors: Linko K. , Tigerstedt I.
Published: January 2009

Eleven of 21 patients having received more than 10 units of whole blood developed hyperpotassemia during the rapid phase of transfusion. The increase in serum potassium from initial values correlated well (r=0.74) with the rate of the transfusion. Three of the hyperpotassemic patients developed cardiac arrest but no life‐threatening arrhythmias were registered in the normokalemic patients. In contrast to most previous studies, transient hyperpotassemia often necessitating aggressive therapy was quite common in our massively transfused patients.
Pharmacokinetics and Placental Transmission of Fazadinium in Elective Caesarean Sections
Authors: Rainaldi M. P. , Busi T. , Melloni C. , Boschi S.
Published: January 2009

The pharmacokinetics and placental transmission of fazadinium (0.75‐0.80 mg kg‐1) were studied in seven pregnant women undergoing elective caesarean section. Plasma levels of the drug were determined by a spectrofluorimetric method and pharmacokinetics were derived according to a 2‐compartment open model. Distribution and elimination half‐lives averaged 0.07 ±0.03 (t½alpha) and 1.24 ± 0.34 (t½ beta) h; the volume of distribution was 20.75± 5.81 1, and the plasma clearance was 202.33 ± 39.2 ml min‐1 1.73 m2. The ratio between umbilical venous blood and maternal blood at delivery ranged from 2.57 to 17.5%. Urinary elimination accounted for 37% of the injected dose within 24 h. It is concluded that because of early good intubating conditions and favourable pharmacokinetics with a modest placental passage, fazadinium might be particularly useful in obstetrics.
Effects of Venous Air Embolism on the Cardiovascular System and Acid Base Balance in the Presence and Absence of Nitrous Oxide
Authors: Mehta M. , Sokoll M. D. , Gergis S. D.
Published: January 2009

Cardiovascular responses and acid‐base changes with graded volumes of intravenously injected air were measured in dogs anesthestized with pentobarbital and either 100% oxygen or 50% oxygen and nitrous oxide. Mean arterial blood pressure decreased significantly with 2.5 ml of air/kg in the oxygen group and at all volumes in the nitrous oxide group. The volume of air embolus appeared to increase more than twice in the presence of 50% nitrous oxide. Pulmonary artery wedge pressure increased significantly in both groups, while end‐tidal carbon dioxide decreased significantly in both groups. The changes in pulmonary artery wedge pressure and end‐tidal carbon dioxide were simultaneous, suggesting that the less invasive monitoring technique may be utilized in diagnosing significant air embolism. Right atrial pressure increased while left atrial pressure decreased significantly in both groups. With injected volumes of 2.0 and 2.5 ml or air/kg, right atrial pressure exceeded left atrial pressure creating the potential of paradoxical air embolism. The pH and Pao2 decreased while Paco2 increased significantly during air embolization.
Bradycardia and Cardiac Asystole Following a Single Injection of Suxamethonium
Authors: SørensenM.D. M. , Engbæk J. , VibyMogensen J. , Guldager H. , Jensen F. Molke
Published: January 2009

Twenty cases of severe bradycardia, including 12 cases of cardiac asystole, following administration of a single dose of suxamethonium to 17 adult patients are presented. Treatment consisted of i.v. atropine in 16 cases, and in four cases external cardiac massage or a precordial thump was also given. Remission was complete in all cases. The mechanism is not known, but it is suggested that i.v. administration of fentanyl at induction may enhance the tendency to bradycardia following suxamethonium. Absence of preoperative atropine may also be of importance.
Transcutaneous Oxygen Measurement During One‐Lung Anaesthesia
Authors: Salmenperä M. , Heinonen J.
Published: January 2009

The value of continuous transcutaneous oxygen tension (Ptco2) monitoring was assessed during the rapidly changing conditions of oxygenation associated with the commencement of one‐lung ventilation (OLV) during thoracic surgery. In ten patients anaesthetized with enflurane‐N2O (Fio2 0.5), PaO2, Ptco2,“cardiac output and arterial pressure were measured first during two‐lung ventilation (TLV) and thereafter at frequent intervals during OLV. These variables remained stable during TLV. The mean Pao2 dropped from 24.9 kPa to 11.4 kPa during the first 10 min of OLV. The accompanying decrease in Ptco2 was slower, the mean PtcO2 being 1.3‐2.1 kPa higher than Pao2. Ptco2 correlated well with Pao2 during OLV (r = 0.907). The elevated PtcO2 index (PtcO2/PaO2) may be partly due to the delayed response of the Ptc02‐detection system in vivo. It is concluded that transcutaneous oxygen monitoring may be used to assess oxygenation in those cases where arterial cannulation is not feasible or if the laboratory conditions cause an undue delay between blood sampling and obtaining the blood‐gas data.
Antidiuretic Hormone Response to Osmotic Stimulus under Fentanyl Anaesthesia
Authors: Ecoffey C. , Simon D. , Samii K. , Diraison P. M. , Poggi J. , Noviant Y. , Ardaillou R.
Published: January 2009

The effect of fentanyl anaesthesia on the plasma antidiuretic hormone (ADH) response to osmotic stimulus was studied in eight patients. Eight g (137 mmol) NaCl were rapidly injected intravenously the day before anaesthesia and blood samples were collected 5, 10, 20 and 30 min after the injection. This protocol was repeated in the same subjects, under anaesthesia with thiopental, nitrous oxide and fentanyl before surgical incision. Plasma ADH markedly increased after NaCl administration and was significantly correlated with plasma sodium (r = 0.67, P< 0.005) when the patients were awake, whereas it did not change over 30 min and was not correlated with plasma sodium (r = 0.18, P>0.05) under fentanyl anaesthesia. This inhibitory effect of anaesthesia occurred in spite of a significant fall in the mean arterial pressure during the study. In order to eliminate the role of overnight fasting, premedication and fluid load, the same protocol was performed in six control patients who were fasted overnight, premedicated and fluid loaded. These results demonstrate that fentanyl anaesthesia abolishes the plasma ADH response to both osmotic and low arterial pressure stimuli.
Differential Ventilation and Selective PEEP During Anaesthesia in the Lateral Decubitus Posture
Authors: BaehrendtzM.D. S. , Klingstedt C.
Published: January 2009

The potential of differential ventilation (DV) with selective positive end‐expiratory pressure (PEEP) has been tested versus conventional ventilation with and without general PEEP. Gas exchange and central haemodynamics were studied in 15 subjects with no clinical or radiological signs of pulmonary disease. The rationale of the method was to ensure ventilation of the well‐perfused dependent lung and to counteract airway closure within that lung. The subjects were intubated with a double‐lumen catheter prior to scheduled abdominal surgery. During general anaesthesia in the lateral posture, they were given DV. The mean inspired oxygen fraction was 0.32. Fifty per cent (“even” tidal volume (VT) distribution) or 70% (“inverted” VT distribution) of the inspired volume was administered to the dependent lung. Two synchronized ventilators were used. In eight subjects DV was also combined with PEEP applied solely to the dependent lung (selective PEEP). The major findings were that DV with even VT distribution reduced venous admixture by 26% (P<0.05) and the alveolo‐arterial oxygen tension gradient (P(A‐a)o2) by 30% (P<0.05) in comparison with conventional ventilation in the lateral position. The addition of selective PEEP further reduced the P(A‐a)o2 by 13%. P(A‐a)o2 was consequently 43% lower than during conventional ventilation without PEEP in the lateral posture (P<0.01). Selective PEEP also had less impact on cardiac output than general PEEP (P<0.05). It is concluded that DV with even distribution of VT and selective PEEP can reduce the P(A‐a)o2 in anaesthetized lung‐healthy subjects in the lateral position.
Partial Curarization in the Postoperative Period
Authors: Lennmarken C. , Löfström J. B.
Published: January 2009

Forty‐eight patients subjected to elective surgery were randomly selected for evaluation of neuromuscular transmission in the postoperative period. All patients were anaesthetized with thiopentone, nitrous oxide, fentanyl and pancuronium. On arrival in the postoperative ward, alertness, ability to sustain head lift and the train‐of‐four (TOF) ratio were estimated. Twenty‐five percent of the patients had a markedly impaired neuromuscular transmission which was not acceptable from a clinical standpoint. The given dose of pancuronium was not excessively high and a fairly long time had elapsed between reversal and TOF‐ratio measurement. There was a poor correlation between TOF ratio and ability to sustain head lift. The study indicates that residual curarization is a not uncommon fact which clinically is hard to assess. The only way to avoid residual curarization seems to be to monitor the neuromuscular transmission during anaesthesia.
The Effect of Sodium Citrate on the pH and the Amount of Gastric Contents Before General Anaesthesia
Authors: Schmidt J. F. , Sghierup L. , Banning A.‐M.
Published: January 2009

Sixty patients were prospectively studied with respect to the volume and pH of their gastric contents after allocation to one of three preoperative treatments. All patients received diazepam (Apozepam®) 5 mg the night before operation and 10 mg at 06.30 on the morning of operation. One group received sodium citrate solution 50 ml perorally at 06.30, 75–370 min before operation. A second group received water 50 ml perorally at 06.30, 100–405 min before operation. The third group received 50 ml water at 06.30 and 50 ml sodium citrate solution perorally just before admission to the operation theatre, 15–50 min before aspiration. Statistical analysis showed elevated pH and volume of gastric contents in the group receiving water in the morning and sodium citrate solution just before admission to the operating theatre immediately after induction of anaesthesia. There was no statistically significant difference of pH and aspirated volume between the group receiving water and the group receiving sodium citrate at 06.30.
The Modifying Effect of Spinal Anaesthesia on Intra‐ and Postoperative Adrenocortical and Hyperglycaemic Response to Surgery
Authors: Møller I. W. , Hjortsø E. , Krantz T. , Wandall E. , Kehlet H.
Published: January 2009

Plasma Cortisol and glucose were measured in 24 patients undergoing abdominal hysterectomy during spinal anaesthesia with 0.5% hyperbaric tetracaine or neurolept anaesthesia. The sensory level of analgesia to pinprick extended to at least T4 before skin incision in the spinal group. The mean sensory analgesic level regressed almost linearly, reaching the fourth lumbar segment 4 h after incision. Plasma Cortisol and glucose measurements from before to 9 h after skin incision showed significant increases in both parameters during and after surgery. Plasma Cortisol and glucose levels were significantly lower during and immediately after surgery in the spinal group, but later postoperatively the mean levels were similar in the two groups. The increase in plasma Cortisol 1 h after skin incision in the spinal group correlated to the segmental level of analgesia at that time (r = 0.77, P<0.01) and a similar correlation was found with regard to plasma glucose changes (r = 0.60, P<0.05). The regression lines showed that maintenance of a sensory analgesic level about the fourth thoracic segment prevented the adrenocortical and hyperglycaemic response to surgery. These findings are in accordance with the anatomical assumption that the upper segmental level of visceral afferent input to the spinal cord is about the fourth thoracic segment. Our results further demonstrate that the inhibitory effect of spinal anaesthesia on the stress response to surgery is transient, and correlates to the regression of sensory analgesia.
Spinal Anesthesia in Sheep with Local Anesthetic Solutions at pH 4 and pH 7
Authors: AdamsPh.D. H. J. , Charron D. M. , Takman B. H.
Published: January 2009

Spinal anesthesia was performed in sheep, using five widely‐used local anesthetic agents. The durations of sensory and motor block were shortest with procaine and longest with bupivacaine and tetracaine. The durations of block with prilocaine and mepivacaine fell between those of procaine and bupivacaine. These results agree with what we know about the relative durations of action of these agents in man. All solutions were tested at pH 4 and pH 7, but, except for prilocaine, there were no differences in the mean durations of sensory and motor block at the two pH levels. Sensory block with prilocaine solution at pH 7 was about 20% longer than at pH 4. With all the compounds except prilocaine, the frequency of motor block in the hind limbs was lower at pH 7 than at pH 4. We conclude that single injections of unbuffered solutions of these agents at pH 4 are as effective in terms of onset and duration as solutions at pH 7. The results of this study reconfirm the usefulness and reliability of the sheep as a model for evaluating and comparing spinal anesthetics.
The Influence of Anticoagulation on Acid‐Base Status and Blood‐Gas Analysis
Authors: Börner U. , Müller H. , Höge R. , Hempelmann G.
Published: January 2009

The results of acid‐base status and blood‐gas analysis can be influenced massively by incorrect sampling. We found that the addition of heparin has no great effect on blood‐gas measurement. Citric acid and fluoride can also be admixed to blood samples in the usual concentrations without severe side‐effects. The major error in the determination of blood gases and acid‐base status is a consequence of even minimal dilution: filling the deadspace of a syringe with any diluent leads to unacceptable results. Hence, we conclude that blood specimens for determination of blood gases and acid‐base status should be taken in specially prepared syringes containing the anticoagulant in the form of a dry substance. We think that citric acid is also acceptable for anticoagulation. Fluoride should be added in order to minimize alterations of pH due to anaerobic glycolysis.
Depression of Monocytes and Lymphocytes by Stress‐Related Humoral Factors and Anaesthetic‐Related Drugs
Authors: Hole A.
Published: January 2009

The in vitro effects of six anaesthesia‐related drugs and five stress‐related serum factors on monocyte‐mediated cytolysis and thymidine uptake in mitogen‐(PHA)‐stimulated lymphocytes have been studied. Thiopentone depressed both the monocyte and lymphocyte function in a dose‐dependent way. However, at thiopentone concentrations which may be present in the serum after a single intravenous anaesthesia induction dose, the monocyte depression was moderate and depression of the lymphocytes was not observed. The other drugs tested, fentanyl, morphine, pancuronium, diazepam and bupivacaine, did not alter the cellular functions significantly. Prostaglandin‐E2 in concentrations of 10‐6 and 10‐7 M markedly depressed monocyte‐mediated cytolysis. Cortisol, catecholamines and serotonin did not alter this function. However, a synergistic depressive effect of the combination of prostaglandin^ and Cortisol was observed. The proliferative response of PHA‐stimulated lymphocytes was depressed by Cortisol in concentrations of 2200 nmol/1 and 1100 nmol/ I. Again, there was a marked synergistic effect of the combination of Cortisol and prostag!andin‐E2, while prostaglandin‐E2 alone, catecholamines and serotonin did not influence the PHA‐response. A possible explanation for the depression of monocyte‐mediated cytolysis and lymphocyte‐thymidine uptake during and after surgery under general anaesthesia may be the combined effect of endocrine and local stress factors.
Per‐ and Postoperative Monocyte and Lymphocyte Functions: Effects of Sera from Patients Operated Under General or Epidural Anaesthesia
Authors: Hole A.
Published: January 2009

Effects on monocyte‐mediated cytolysis and thymidine uptake in PHA‐stimulated lymphocytes were studied with cells from healthy donors and sera from patients undergoing hip replacement under epidural‐ or general anaesthesia. Sera were sampled before induction of either epidural‐ or general anaesthesia (I), 15 min after induction of anaesthesia (II), during surgery 60–90 min after start of induction of anaesthesia (III), and the next morning at 8 o'clock (IV). Serum sample II from patients operated under general anaesthesia significantly depressed both monocyte cytolysis and thymidine uptake in lymphocytes. At sampling time III and IV the monocyte cytolysis was insignificantly reduced. There was no suppression of lymphocyte‐thymidine uptake at these sampling times. The sera from patients operated under epidural anaesthesia did not influence the thymidine uptake in lymphocytes. However, sera drawn from epidural anaesthesia patients at sampling time IV significantly depressed the monocyte cytolysis (the sample was drawn the next morning 3–4 h after discontinuation of the epidural anaesthesia). We conclude that the depressive effect of surgery under general anaesthesia on monocyte cytolysis and lymphocyte proliferation is partly transferable by serum factors. The depressive effects on monocytes and lymphocytes of sera drawn 15 min after induction of general anaesthesia may be due to the effect of the induction of thiopentone.
T‐Lymphocytes and the Subpopulations of T‐Helper and T‐Suppressor Cells Measured by Monoclonal Antibodies (T11, T4, and Ts) in Relation to Surgery Under Epidural and General Anaesthesia
Authors: Hole A. , Bakke O.
Published: January 2009

Monoclonal antibodies reacting with specific determinants on lymphocytes and their subpopulations were used to study the influence of surgery under general or epidural anaesthesia on the number of T‐cells (T11), T‐suppressor cells (T8), and T‐helper cells (T4). The T‐cell fraction decreased significantly during surgery, but was only moderately reduced on the first postoperative day. The change in the T‐cell fraction was the same under both types of anaesthesia. The helper and suppressor cell fractions were not significantly altered at any time during the study, and again there was no difference between the two anaesthetic regimens. The ratio of helper cells to suppressor cells (the T4/T8 ratio), which is widely used as an indicator of immunosuppression, showed no significant variations during the study, even though there were individual variations. Changes in the T4/T8 ratio were not correlated to the amount of blood transfusions, nor was there any correlation between the T4/T8 ratio and the thymidine uptake in mitogen‐(PHA)‐stimulated lymphocytes. T‐lymphocytes are depressed during and after surgery under general anaesthesia. From the present study, this does not seem to be due to changes in the balance between helper‐ and suppressor T‐cells.
Efficacy of Clear Antacid Prophylaxis in Obstetrics
Authors: Abboud T. K. , Curtis J. , Earl S. , Henriksen E. H. , Hughes S. C. , Levinson G. , Shnider S. M.
Published: January 2009

We studied 33 women scheduled to undergo general anesthesia for cesarean section. Prior to induction of anesthesia, each patient received in a random fashion one of two prophylactic antacids. Group I (n= 17) received 30 ml Gelusil® orally and Group II (n=16) received 30 ml of 0.3 mol/1 sodium citrate. After induction of general anesthesia an oro‐gastric tube was passed. The amount and pH of the gastric aspirate were measured at the time of delivery and 45 min after delivery “before extubation.” Both antacids elevated gastric pH above 3.5 in all patients but one in the Gelusil group. The pH remained elevated 45 min later. It is concluded that 0.3 mol/1 sodium citrate is effective as an antacid when given orally prior to induction of anesthesia.
Comparison of Paracetamol and Pentazocine Suppositories for Pain Relief after Tonsillectomy in Adults
Authors: Saarnivaara L.
Published: January 2009

The pain‐relieving effect of paracetamol 500 mg or pentazocine 50 mg suppositories was studied in 91 voluntary adult patients after tonsillectomy in halothane or enflurane anaesthesia. Both suppositories were studied after both anaesthetics. Thus the patients were randomly allocated to four study groups. At 60 min after administration of coded suppositories, 46–50% of the patients in various groups needed extra analgesic and received pethidine 1 mg/kg i.m. Thereafter, the pain relief was satisfactory in all groups until the end of the observation period (120 min). The incidence of vomiting, the most common side effect, ranged from 5 to 14% in the groups. Bleeding from the operation site was most common (14%) in the patients treated with pentazocine after enflurane anaesthesia and did not occur in the patients treated with pentazocine after halothane anaesthesia. The incidence of bleeding in both paracetamol groups was 9%. In all cases, bleeding stopped without any special treatment. The results suggest that both paracetamol 500 mg and pentazocine 50 mg suppositories in the doses used were weak analgesics for throat pain after tonsillectomy in adults in the early postoperative period. The incidence of side effects was relatively low.