bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of plasma volume variations on the calcium concentration during epidural anaesthesia
Authors: Kancir C. B. , Petersen P. H. , Wandrup J.
Published: January 2009

The plasma variations of the ionized and total calcium concentration in relation to protein concentration and plasma volume were studied in 12 patients during epidural anaesthesia for transurethral prostatectomy. The most significant changes were noted during the onset of anaesthesia. From arrival in the operating theatre to start of operation, the plasma concentration of ionized calcium decreased from 1.28 (s.d. = 0.05) mmol/l to 1.22 (s.d. = 0.04) mmol/l and total calcium decreased from 2.39 (s.d. = 0.11) mmol/l to 2.17 is.(s.d. = 0.10) mmol/l. At the same time, however, the decrease in ionized calcium concentration and the increase in plasma volume were associated with a rise of 10.3% in the pool of free calcium ion in plasma. After the start of surgery, the plasma ionized calcium concentration remained almost unaffected throughout the rest of the study period. The total plasma calcium concentration as well as the total protein concentration remained stable during operation, only increasing after the end of surgery. The preoperative changes in the plasma calcium concentration may have been the result of both haemodilution and mobilization of calcium ions from its bone stores. Postoperatively, an increased urinary loss of calcium must have followed the administration of furosemide at the end of surgery.
Neutrophil mobility during anaesthesia in children. A trial of ascorbate premedication
Authors: Charlton A. J. , Harvey B. A. , Hatch D. J. , Soothill J. F.
Published: January 2009

In 20 healthy children undergoing elective surgery, mobility of neutrophils, both unstimulated and stimulated by endotoxin, was studied using a millipore filter system with microscopic determination of leading front migration. Paired samples were incubated with 10‐2 mol l‐1 calcium ascorbate and ten children also received 10 mg kg‐1 ascorbic acid before premedication. Stimulation of mobility was reduced after the opioid premedication (P < 0.05) in the ascorbate group only, hut not significantly during anaesthesia and surgery. A few individuals showed persisting abnormally low values. No effect of ascorbate in vivo or in vitro was demonstrated. There were no infrations.
Aminophylline reduces the depth and duration of sedation with barbiturates
Authors: Krintel J. J. , Wegmann F.
Published: January 2009

Aminophylline, an inhibitor of cyclic nucleotide phosphodiesterase, has for many years been used to relieve bronchospasm. Recent reports have shown that aminophylline antagonizes morphine and diazepam sedation. To see if aminophylline acts similarly on barbiturate sedation, we examined 24 women undergoing short general anaesthesia with thiopental (7 mg · kg‐1), using a double‐blind study design. Evaluated by continuous auditory reaction time measurements, aminophylline (5.6 mg · kg‐1) reduces the depth and duration of sedation with thiopental. This suggests that aminophylline could be used to diminish an unwanted effect of barbiturate sedation.
Effects of repeated doses of benzodiazepines on arterial blood gases and transcutaneous Po2
Authors: Eriksson I. , Berggren L.
Published: January 2009

The effects of repeated doses of benzodiazepines, diazepam and midazolam in combination with meperidine. on arterial blood gases and transcutaneous Po2 were studied in eight healthy volunteers. The study was designed to mimic a clinical situation. Initially two doses of either midazolam 0.05 mg/kg or diazepam in fat emulsion 0.15 mg/kg were given in a randomized crossover fashion with a 20‐min interval, followed by meperidine 0.5 mg/kg another 20 min later. The opioid effects were then antagonized by naloxone 0.4 mg. The initial doses of benzodiazepines caused an increase in Paco2 and a decrease in Pao2. The changes in Pao2 were of short duration and recovered to baseline levels between injections. However, they came sooner and were more pronounced after midazolam. The changes in Ptco2 paralleled those in Pao2. The PtcO2 index as a measure of cardiac output and peripheral blood flow adequacy was increased immediately after the first injection of midazolam but was otherwise not different from control. There were no differences between the drugs concerning PtcO2 index. Paco2 increased after the first benzodiazepine injection and remained so throughout the study. Addition of meperidine caused only small changes in Pao2 and Paco2. These changes were recieved by naloxone. In spite of different elimination kinetics there was no difference in the duration of respiratory depression between the two benzodiazepines.
Effects of droperidol on peripheral vasculature: use of cardiopulmonary bypass as a study model
Authors: Videcoq M. , Desmonts J.‐M. , Marty J. , Hazebroucq J. , Lanclois J.
Published: January 2009

The effects of droperidol on the systemic vascular resistance (SVR) and the venous caparitaiire were studied during cardiopulmonary bypass (CPD) in 24 patients. CPD was performed with either pulsatile or non‐pulsatile flow. During non‐pulsatile flow, droperidol (0.15 mg·kg‐1 and 0.30 mg·kg‐1) decreased SVR and increased venous capacitance. These values were significantly different after the 2nd and the 7th min, respectively. During pulsatile flow, the initial SVR was lower. The decremental effect of 0.30 mg·kg‐1 droperidol on SVR was proportional to the preinjection level of SVR (r = 0.64). The increase in venous capacitance related to droperidol was independent of the dose and of the type of flow in all patients. It can be concluded that the vasodilating action of droperidol during CPB on the arterial bed is transient, independent of dose, and related to the preinjection level of SVR. The effect of droperidol on veuous capacitance is not as rapid but has a longer duration.
Pulmonary ventilation and gas exchange in children anaesthetized with halothane, enflurane and isoflurane
Authors: Johannesson G. P. , Lindahl S. G. E.
Published: January 2009

The effects of similar anaesthetic levels of halothane (1.3 MAC), enflurane (1.2 MAC) and isofluranc (1.1 MAC) on pulmonary ventilation and gas exchange were investigated in 24 children subjected to minor and intermediate paediatric surgical procedures. Eight children were anaesthetized with each agent, pncumotarhography and capnography were used, and airway as well as oesophageal pressures were measured. Minute ventilation (V́E) was lower with enflurane than with halothane (P<0.001) and isoflurane (ns). Tidal volumes were, however, similar and variations in V́E were thus caused by lower respiratory rates with enfluranc than with the two other agents. Alveolar ventilation (V́BohrA) and carbon dioxide elimination (V́co2) were smaller and end‐tidal CO2 tension higher with enflurane. Ventilatory efficiency was, however, somewhat better with enflurane as indicated by lower VBohrD (ns) and V́e/V́co2 (P < 0.05) ratios compared with the two other agents. The effects of all three agents on dynamic compliance were similar, while total pulmonary resistance was less with isoflurane than with halothane and enflurane. It is concluded that although minute ventilation was smaller with enflurane than with halothane and isoflurane, ventilatory efficiency was similar due to a smaller dead space ventilation as a result of the lower respiratory rates in children anaesthetized with enflurane.
Changes in breathing pattern and chest wall mechanics after benzodiazepines in combination with meperidine
Authors: Berggren L. , Eriksson I. , Mollenholt P.
Published: January 2009

The effects of repeated sedative i.v. doses of midazolam and diazepam in combination with meperidine on breathing pattern and thoracoabdominal motion were studied in eight healthy male volunteers. At 20‐min intervals in a randomized double‐blind crossover design the subjects initially received two doses of midazolam 0.05 mg/kg or diazepam 0.15 mg/kg followed by meperidine 0.5 mg/kg and then naloxone 0.4 mg. Breathing pattern and thoracoabdominal motion were measured non‐invasively, utilizing a computerized strain gauge technique. The initial injection of both benzodiazepines caused significant decreases in tidal volume, inspiratory time and expiratory time. There were no significant differences between the two drugs in any of these variables. Minute ventilation, mean inspiratory flow and respiratory timing were not significantly affected. The second injection of both benzodiazepines caused only insignificant additional changes. When meperidine was added, the effects on inspiratory time and tidal volume were small and not significant. However, expiratory time increased and was no longer significantly different from control. The injection of naloxone reversed the meperidine‐induced changes only, and the breathing pattern was no longer different from that obtained during benzodiazepines alone. The decrease in tidal volume after the henzodiazepines was almost exclusively mediated by a decrease in the abdominal contribution. Additional doses of benzodiazepines did not enhance these changes. However, meperidine caused a further decrease in the abdominal contribution. This decrease was reversed by naloxone. This indicates that the combination of benzodiazepines and meperidine caused a profound decrease in diaphragmatic performance.
The efficacy of ranitidine in children
Authors: Goudsouzian N. G. , Young E. T.
Published: January 2009

The effect of preoperative oral ranitidine on intragastric pH and volume of aspirate was evaluated in anaesthetized children. Five groups of eight randomly assigned children were evaluated. The first group acted as control and the other groups received 2, 2.5, 3, 3.5 mg kg‐1 ranitidine, respectively. The drug was administered 1–4 h preoperatively. The intragastric pH was measured by a pH electrode through an orogastric tube, and the volume of aspirate was recorded every hour. At the time of first measurement oral ranitidine was significantly effective (P < 0.001) in increasing the pH of intragastric contents to above the safe level of 2.5 in 94% of the children. At the second measurement an hour later, it was effective in all the children. Ranitidine has no significant effect on the volume of gastric aspirate and also there was no significant difference in the effect on the pH of the various doses of ranitidine studied. Oral ranitidine at doses of 2–3.5 mg kg‐1 is effective in decreasing gastric acidity in children.
Thoracic and abdominal lymph drainage in relation to mechanical ventilation and PEEP
Authors: Frostell C. , Blomqvist H. , Hedenstierna G. , Halbig I. , Pieper R.
Published: January 2009

Thoracic and abdominal lymph flow have been studied in 25 dogs. Thoracic lymph flow (TLF) was found to be (mean ± s.e. mean) 6.1 ± 1.4 ml/h before, and 29 ± 4.6 ml/h after the induction of lung damage with oleic acid. TLF was depressed by 50% both before and after lung damage, when a positive end‐expiratory pressure (PEEP) of 1.0 kPa (10 cmH2O) was applied. This suggests impeded drainage of the lung tissue. Spontaneous breathing, compared to mechanical ventilation, significantly increased TLF by approximately 70%. Abdominal lymph flow increased from 61 ± 5.3 ml/h to 111 ± 12.6 ml/h, when a PEEP of 1.0 kPa was applied. These findings demonstrate that PEEP may contribute to oedema in a surgical area. It is concluded that increased intrathoracic pressure reduces TLF, and spontaneous breathing increases TLF, as compared to mechanical ventilation without PEEP.
Cardiovascular effects of pentobarbital in pigs, and the lack of response to naloxone in pentobarbital induced circulatory failure
Authors: Strøm J. , Häggmark S. , Reiz S. , Sørensen M. Bredgaard
Published: January 2009

The hemodynamic effects of pentobarbital were tested in an experimental model used for cardiovascular research. Anesthesia was induced with an i.v. bolus and maintained with a continuous infusion of pentobarbital. The cardiovascular performance was then evaluated at various pentobarbital plasma concentrations ranging from 25 to 100 mg·l‐1. Optimal experimental conditions were found at plasma pentobarbital concentrations within the range 40–60 mg·l‐1, as the animals were well anesthetized with intact hemodynamics or ECG. The method of continuous pentobarbital administration seems advantageous for experimental research. Circulatory impairment following pentobarbital overdose was not affected by naloxone.
Gas exchange in low‐compression HFPPV is maintained at low distending pressures in the pig
Authors: Sjöstrand U. H. , Smith R. B. , Bunegin L. , Helsel P. , Herrera‐Hoyos J. O. , Wennhager M. B. , Borg U. R. , Bready L. L.
Published: January 2009

The fact that collateral ventilation normally occurs in the human lung has led to the suggestion that it might contribute to the successful clinical effects of low‐compression high‐frequency positive‐pressure ventilation (HFPPV). As the pig has poor collateral ventilation, pulmonary vasoconstriction has to be part of the regulatory mechanisms matching ventilation‐perfusion. A study was made on nine pigs anesthetized with ketamine hydrochloride intravenously to elucidate the maintenance of ventilation‐perfusion balance during mechanical ventilation. Comparisons were made between the ventilatory patterns provided by a conventional ventilator (Servo‐Ventilator 900C) and an improved prototype of a low‐compression system for volume‐controlled ventilation (system H). A ventilatory frequency of 20 breaths per min (bpm) with SV‐900C (SV‐20) and system H (H‐20) and of 60 bpm with system H (H‐60) was used. The experimental conditions were otherwise identical. Positive end‐expiratory pressures (PEEP) were applied to maintain the same mean airway pressure with the three systems. The tidal volume required for normoventilation differed significantly between the three ventilatory patterns, but there were no differences in circulatory and oxygen‐transport variables. By measurements of airway pressure and intrapleural liquid surface pressure, it was demonstrated that the distending pressure (at end‐inspiration) was significantly lower with a low‐compression system (H‐20 versus SV‐20), especially at a high ventilatory frequency (H‐60 versus H‐20). Consequently, although the mean airway pressure was set at the same level for the three different ventilatory modalities, the distending pressures required for the same alveolar ventilation and arterial oxygenation differed significantly. H‐20 and H‐60, and especially H‐60 (= HFPPV) provided ventilation with the lowest distending pressure. Thus the barotrauma of mechanical ventilation was lower during H‐60 than SV‐20. The present results show that low‐compressive patterns of ventilation and HFPPV allow adequate gas exchange in animals without collateral ventilation.
Dose‐related effects of isoflurane on superior mesenteric vasoconstriction induced by endotoxemia in the rat
Authors: Biber B. , Schaefer C. F. , Smolik M. J. , Lawrence M. C. , Lerner M. R. , Brackett D. J. , Wilson M. F. , Fagraeus L.
Published: January 2009

To investigate the interplay between endotoxin‐induced circulatory shock and the cardiovascular effects of different doses of isoflurane, mean aortic pressure (MAP), central venous pressure (CVP), mean pulmonary arterial pressure (MPAP), heart rate (HR), cardiac output and superior mesenteric artery flow (SMAF), were monitored in rats anesthetized with either 1.4% or 2.0% isoflurane in oxygen. Cardiac index (CI), total peripheral vascular resistance (TPR) and superior mesenteric vascular resistance (SMVR) were derived. During continuous administration of isoflurane, endotoxin (LDW90, 40 mg·kg‐1iv) was given after a 30‐min baseline period, and data were collected for an additional 2‐h period. Sham‐challenged (saline) animals served as controls. The response to endotoxin in the systemic circulation showed a decrease in CI and MAP, while HR and TPR increased. MAP and CVP were essentially unchanged. There were no significant differences in thesystemiccirculation variables between endotoxin groups, apart from a more pronounced HR increase during 1.4% isoflurane.Regionally, however, SMAF was lower and SMVR was higher in the 2.0% versus the 1.4% isoflurane group following endotoxin. To conclude, the degree of mesenteric vasoconstriction during endotoxemia was dependent on the dose of isoflurane. This dose‐related effect seems to be mediated through interaction with intrinsic vascular control, a higher dose allowing a more pronounced local blood flow reduction.
Comparison of atracurium and vecuronium in anaesthesia for renal transplantation
Authors: Orko R. , Heino A. , Björkstén F. , Scheinin B. , Rosenberg P. H.
Published: January 2009

In a controlled study, equipotent doses of atracurium (20 patients) or vecuronium (22 patients) were given randomly to patients with chronic renal failure anaesthetized for renal transplantation. There were no statistically significant differences in the degree of muscle relaxation (electromyographic twitch response) and circulatory parameters. Plasma histamine concentration increased in three patients after the first dose of atracurium, but in none of the patients could any signs of allergic reactions be observed. Tracheal intubation was difficult in six patients of the atracurium group, all of whom had diabetes mellitus and varying degrees of neck stiffness. The neuromuscular block response in diabetic uraemic patients was similar to that in other uraemic patients.
Cerebral blood flow, cerebral metabolic rate of oxygen and relative CO2‐reactivity during craniotomy for supratentorial cerebral tumours in halothane anaesthesia. A dose‐response study
Authors: Madsen J. B. , Cold G. E. , Hansen E. S. , Bardrum B.
Published: January 2009

Fourteen patients were studied during craniotomy for small supratentorial cerebral tumours. Cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRo2) were measured twice by a modification of the Kety‐Schmidt technique using 133Xe intravenously. Anaesthesia was induced with thiopental 4–6 mg kg‐1, fentanyl and pancuronium, and maintained with an inspiratory halothane concentration of 0.45% in nitrous oxide 67% at a moderate hypocapnic level. In one group of patients (n = 7) the inspiratory halothane concentration was maintained at 0.45% throughout anaesthesia. About 1 h after induction of anaesthesia CBF and CMRo2 averaged 35 ± 2 ml 100 g‐1 min‐1 and 2.7 ± 0.3 ml O2 100 g‐1 min‐1 (mean ± s.e mean), respectively. During repeat studies 1 h later CBF and CMRo2 did not change. In another group of patients (n = 7) an increase in halothane concentration from 0.45% to 0.90% was associated with a significant decrease in CMRo2 from 2.3 ± 0.1 to 2.0 ± 0.1 ml o2 100 g‐1 min‐1. The CO2 reactivity measured after the second flow measurement was preserved. It is concluded that halothane in this study induces a dose‐dependent decrease in cerebral metabolism, an increase in CO2 while CO2‐reactivity is maintained.
In vitro diagnosis of susceptibility to malignant hyperthermia: evaluation of tests with halothane‐caffeine, potassium chloride, suxamethonium and caffeine‐suxamethonium
Authors: ØRding H. , Skovgaard L. T.
Published: January 2009

Susceptibility to MH was determined in 77 patients according to the protocol of the European MH Group. Additional muscle bundles were used for diagnostic in vitro tests with caffeine in the presence of 1 % halothane, potassium chloride, suxamethonium, and caffeine‐suxamethonium. Significant differences between MH‐susceptible (MH) and MH‐negative (MHN) patients were obtained with the halothane‐caffeine test and the potassium chloride test, whereas no differences were found with the suxamethonium test. In the test with caffeine‐suxamethonium, a different response to caffeine but not to suxamethonium was obtained. In all tests there was an overlap in results between MHS and MHN groups, and the predictive values of the tests ranged between 63 and 95%. Prior small doses of caffeine followed by a 4 mmol/l dose of caffeine elicited significantly smaller contractures than 4 mmol/l given as the first dose of caffeine. This underlines the necessity of a common protocol for performance and interpretation of diagnostic tests for MH.
Sympathetic activity and haemodynamic variables during spinal analgesia in man
Authors: Malmqvist L. Å. , Bengtsson M. , Björnsson G. , Jorfeldt L. , Löfström J. B.
Published: January 2009

At present there is a lack of information concerning haemodynamic changes related to the degree of sympathetic blockade during spinal analgesia. In this investigation, involving 36 patients, changes in haemodynamic parameters were studied in 30 patients receiving spinal analgesia and in six patients having “sham spinal” analgesia. Three local anaesthetic solutions were used: bupivacaine without and with glucose and tetracaine with glucose. Skin conductance responses were used to evaluate changes in provoked sympathetic activity. It was found, as in previous studies, that a complete block of sympathetic activity in the foot was seen in only 60% of patients with an average analgesic level of T 4. A partial sympathetic blockade was registered up to and above the level of analgesia. In 25/30 cases only minor alterations in cardiac output, heart rate, stroke volume, mean arterial pressure and systemic vascular resistance were seen in spinal analgesia whose level reached on average T4–5. In five cases in whom analgesia reached T4‐3, mean arterial pressure fell≥30% with a well‐preserved cardiac output, but with complete sympathetic blockade up to T5, and in two cases also in the hand. Only minor differences were observed between the different anaesthetic solutions.
Central haemodynamics and regional blood flows during thoracic epidural analgesia combined with positive pressure ventilation
Authors: Feuk U. , Jakobson S. , Norlén K.
Published: January 2009

Cardiac output, central haemodynamics and regional blood flows were studied in pigs. The microsphere technique was used for blood flow determinations. Measurements were made during spontaneous breathing (SB) and during intermittent positive pressure ventilation with 0.8 kPa (8 cmH2O) positive end‐expiratory pressure (8 PEEP) before and during thoracic epidural analgesia (TEA). TEA in the pig caused reduced cardiac output due to reduced heart rate with maintained stroke volume. During TEA there was also a reduction of mean arterial blood pressure which ran almost parallel to the decrease in cardiac output with maintained systemic vascular resistance during SB and at 8 PEEP. The distribution of cardiac output was basically the same during SB and at 8 PEEP as it was before TEA. However, myocardial blood flow and relative perfusion decreased during TEA, both during SB and at 8 PEEP. TEA also reduced spinal cord blood flow within the thoracic region during SB and at 8 PEEP.
Premedication with midazolam in out‐patient general anaesthesia. A comparison with morphine‐scopolamine and placebo
Authors: Ræder J. C. , Breivik H.
Published: January 2009

Strong premedication may prolong recovery and cause side‐effects after short surgical procedures in general anaesthesia. To be operated without premedication may be unpleasant for the patient. Midazolam is a water‐soluble benzodiazepine with rapid onset and short half‐life. In a randomized study with 193 female patients, we compared the effects and side‐effects of three different premedicants i.m.: midazolam, morphine‐scopolamine (Mo‐Scop) and placebo. Midazolam and Mo‐Scop had an equal and significantly better effect than placebo on preoperative anxiety and alertness. Side‐effects like nausea, dry mouth and prolonged recovery occurred significantly more often in the Mo‐Scop than the midazolam or placebo groups. The midazolam‐premedicated patients had significantly more amnesia compared with the other two groups. Only 3% of the patients would prefer no medication before anaesthesia, whereas 80% would prefer a combination of an anxiolytic and hypnotic premedication. Sixty‐three percent of the patients would prefer a premedicant administered by injection. The results indicate that midazolam i.m. is an effective premedicant, with few side‐effects, for short procedures in general anaesthesia.
Postoperative analgesia with intrapleural administration of bupivacaine‐adrenaline
Authors: Brismar B. , Pettersson N. , Tokics L. , Strandberg A. , Hedenstierna G.
Published: January 2009

Twenty‐one patients who underwent elective cholecystectomy were studied with regard to the effect of intrapleural administration of bupivacaine‐adrenaline solution on postoperative pain and ventilatory capacity. Administration of 10 or 20 ml of 2.5 mg/ml or 5 mg/ml bupivacaine solution resulted in complete analgesia in 143 of 159 administrations. Most patients experienced the maximal pain‐relieving effect within 1–2 min and analgesia persisted as a rule for 3 5 h. Forced vital capacity and forced expiratory volume in 1 s increased after intrapleural analgesia on average by 56% and 46%, respectively, on the first postoperative day and by 35% and 51%, respectively, on the second day. There was no significant difference in the analgesic effect or in the effect on the ventilatory capacity between the 2.5 mg/ml or the 5 mg/ml solution, in either the 10 ml or the 20 ml dose. Placebo (NaCl) given intrapleurally had no effect on pain or on the ventilatory capacity. The plasma concentration of bupivacaine after intrapleural administration showed a wide interindividual variation, with considerably higher average values when the 5 mg/ml solution had been used than for the 2.5 mg/ml solution. Although no toxic effects were noted, a 2.5 mg/ml solution, which can be given in an initial dose of 20 ml and top‐up doses of 10 ml at 3–6 h intervals, is recommended. In four patients minor pneumothorax developed when the catheter was introduced. The pneumothorax was easily evacuated, but underlines the need for great care when introducing the catheter.
Effects of salbutamol and hyperventilation on the rise in serum potassium after succinylcholine administration
Authors: Inaba H. , Ohwada T. , Sato J. , Mizuguchi T. , Hirasawa H.
Published: January 2009

It is known that circulating catecholamines stimulating betas‐receptors and the acid‐base balance play important roles in the regulation of serum potassium (K+). The present study was undertaken to investigate the effect of salbutamol (SB), a highly selective beta2agonist, and hyperventilation (HV)‐induced alkalosis on the change in serum K.+ after succinylcholine (SCh) administration in dogs. Pretreatment with SB (0.4 μg · kg‐1· min‐1for 30 min) produced sustained decreases in serum K+ and mean arterial pressure, and transient increases in cardiac, output and serum insulin concentration. Maintaining repiratory alkalosis with HV (Paco2= 2.6–3.3 kPa) produced sustained decreases in serum K+ and cardiac output. Although both pretreatment with SB and HV‐induced alkalosis significantly reduced the absolute increases in serum K+ after SCh, the effect of SB was more remarkable than that of HV. These results suggest that the degree of beta2‐receptor activity can strongly modulate the change in serum K+ after SCh administration.
Thoracolumbar epidural anaesthesia blocks the circulatory response to laryngoscopy and intubation
Authors: Wattwil M. , Sundberg A. , Olsson J. , Nordström S.
Published: January 2009

Laryngoscopy and endotracheal intubation cause a stress reaction resulting in an increase in heart rate and systemic blood pressure. This haemodynamic response is considered to be due to a sympathetic discharge caused by stimulation of the upper respiratory tract. This stress reaction during laryngoscopy and endotracheal intubation was studied in patients with total thoracolumbar epidural anaesthesia (EDA). Nine patients with thoracolumbar EDA including at least the segments T1 to L2 were compared to seven patients without EDA during induction of general anaesthesia. The epidural anaesthesia was achieved with 2% mepivacaine with adrenaline. General anaesthesia was induced with thiopentone 4–5 mg/kg followed by 100 mg suxamethonium. The highest blood pressure value during the first 2 min after intubation was compared to the value immediately before intubation. The epidural anaesthesia caused a reduction of the mean arterial blood pressure (MAP) by 25%, and a reduction of the heart rate (HR) by 7%, but neither the induction with thiopentone nor the laryngoscopy and intubation caused any changes in mean arterial blood pressure or heart rate. However, in the control group MAP increased 29% and HR 16%, following intubation. Thus, the T1‐L2 epidural anaesthesia with 2% mepivacaine with adrenaline blocked the blood pressure reaction to laryngoscopy and intubation, and consequently the efferent sympathetic nervous system was completely blocked.
Postoperative ventilatory and circulatory effects of heating after aortocoronary bypass surgery
Authors: Joachimsson P. O. , Nyström S. O. , Tyden H.
Published: January 2009

The effects of postoperative external heat supply on shivering, oxygen uptake, carbon dioxide production, ventilatory requirements and haemodynamic variables were studied postoperatively after aortocoronary bypass surgery in 24 men with stable angina pectoris. After hypothermic cardiopulmonary bypass (CPB) at 25°C, the patients were rewarmed to a nasopharyngeal temperature of at least 38°C, resulting in a rectal temperature of about 34°C before termination of CPB. Twelve patients, forming the control group, were given no other external heat supply. In another group (n = 12), the “radiant heat supply group”, additional external heat was provided postoperatively, the main source of which was a thermal ceiling supplemented with heated, humidified respiratory gases. In this latter group the postoperative rewarming was accomplished earlier and was converted into a mainly passive process. Shivering, oxygen uptake, CO2 production and ventilation volumes were significantly reduced compared with the control group. Cardiac index and stroke index were higher and systemic oxygen extraction was lower in the radiant heat supply group. Postoperative hypertension and vasoconstriction were greatly decreased, suggesting that residual hypothermia is an important cause of the postoperative vasoconstriction.
The lack of response to suggestion under controlled surgical anesthesia
Authors: Woo R. , Seltzer J. L. , Marr A.
Published: January 2009

Thirty‐two ASA I or II women undergoing abdominal hysterectomy were randomly allocated to four groups to determine what type, if any, of recorded intraoperative message they would receive. Groups I and II heard a neutral recording with no verbal content. Group III heard an experimental recording with a positive suggestion for a rapid recovery. Group IV had a self‐prepared message. The tapes were played during general anesthesia when anesthetic depth was judged to be stable and adequate by vital signs, end‐tidal anesthetic concentration and EEG compressed spectral array. No patient reported any recall of intraoperative messages when interviewed on the day after surgery. Chart review showed no difference in days of hospitalization, dose of analgesics required, time to beginning oral intake, or the amount of wound drainage (P<0.05). We conclude that no awareness can be observed directly by recall or indirectly by response to suggestion given under stable and adequate general anesthesia.
Psychological effect of detailed preanesthetic information
Authors: Elsass P. , Eikard B. , Junge J. , Lykke J. , Staun P. , Feldt‐Rasmussen M.
Published: January 2009

Eighty‐one patients admitted for minor surgery were followed with questionnaires and self‐rating scales in the pre‐ and post‐anesthetic period to evaluate the effect of giving either routine or detailed information. The patients were randomly allocated to two groups and received either routinely given information by the anesthetist for about 5 min or more detailed information for at least 20 min. The patients' experience of the effect of the preanesthetic visit was tranquillizing and adequate in both groups. The most significant difference with detailed information was a smaller number of side‐effects like slow cerebration, nausea and a general feeling of discomfort compared to the routinely informed patients. Repetitive ratings on Spielberger's State of Anxiety Scale showed that the patients who had had previous anesthetic experience were less influenced by the degree of information given. In view of the considerable numbers of parameters investigated, there were relatively few significant differences between the groups, and it was concluded that there was no convincing benefit from expanding routine to detailed information.
Atropine sulphate enhances neuromuscular transmission in the rat
Authors: Wali F. A. , Suer A. H. , Dark C. H. , McAteer E. J. , Tugwell A. C.
Published: January 2009

The effect of atropine (0.001–10 μmol ·1‐1) on neuromuscular transmission in the rat hemidiaphragm preparation was investigated by analysing its effects on directly and indirectly‐elicited twitch, tetanic post‐tetanic twitch responses and on the phenomenon of post‐tetanic twitch potentiation. The effect of atropine on contractions produced by endogenous acetylcholine (ACh) or exogenous ACh (added directly into organ bath containing muscle) was studied in rat ileum. The results showed that atropine in low concentrations (1 μmol·1‐1 or less), enhanced the indirectly‐elicited twitch, tetanic and post‐tetanic twitch responses in the rat diaphragm preparation. The mean EC50 value of atropine‐induced increase in twitch tension was 0.08 ± 0.01 μmol·l‐1 (mean ± s. e. mean, n = 6). Atropine had little effect on directly‐elicited twitch tension, but in high concentrations (10 μmol·1‐1 or more), it reduced the directly, and indirectly‐elicited twitch contractions and produced a neuromuscular block in the rat diaphragm preparation. Atropine increased the contraction produced, in rat ileum, by endogenous ACh, i.e. ACh released from the phrenic nerve stimulated at 50 Hz for 20 s duration (control contraction: 1.3 ± 0.1 g, contraction in atropine: 1.7 ± 0.2 g). In contrast, atropine significantly reduced the contraction produced by exogenous ACh in the same preparation (control contraction: 3.0 ± 0.5 g, atropine: 2.0 ± 0.1 g), suggesting that a different mechanism may be involved in the latter effect of atropine. It was concluded that atropine, in low concentration, enhanced neuromuscular transmission, possibly via a presynaptic mechanism. In high concentration, atropine may reduce and then block transmission, possibly via pre‐ and postsynaptic mechanisms.
Relationship between posttetanic count and response to carinal stimulation during vecuronium‐induced neuromuscular blockade
Authors: Fernando P. U. E. , Viby‐Mogensen J. , Bonsu A. K. , Tamilarasan A. , Muchhal K. K. , Lambourne A.
Published: January 2009

The correlation between degree of peripheral neuromuscular blockade and response to carinal stimulation was evaluated in two groups of 25 patients: one group was anaesthetized with thiopental, N2O and halothane, and the other group received thiopental, N2O and fentanyl. The degree of peripheral blockade was evaluated using train‐of‐four (TOF) and posttetanic twitch (PTC) stimulation of the ulnar nerve. The degree of diaphragmatic paralysis was evaluated indirectly by stimulating the carina and observing the corresponding muscular response, which was graded as severe, mild or absent. During halothane anaesthesia a PTC of 0 always indicated that no response to carinal stimulation could be elicited. On the appearance of the first response to posttetanic twitch stimulation (PTC= 1), 2% of the patients showed a mild response to carinal stimulation. At the first response to TOF stimulation, 48% of the patients reacted with a mild response. During thiopental, N2O, fentanyl anaesthesia one of 25 patients showed a mild response to carinal stimulation at a PTC of 0. When PTC was 1, 20% of the patients reacted mildly to the stimulation. At the first response to TOF stimulation, 92% showed a response to carinal stimulation; 24% of these responses were severe, necessitating intervention. It is concluded that the TOF response elicited peripherally is a late sign of neuromuscular recovery of the diaphragm, and that the method of counting posttetanic twitches is superior to the TOF response in evaluating early recovery of this muscle. Further, to ensure total diaphragmatic paralysis, the neuromuscular blockade of the peripheral muscles should be so intense that no response to posttetanic twitch stimulation (PTC = 0) can be elicited.
Post‐operative analgesia by high thoracic epidural versus intramuscular nicomorphine after thoracotomy. Part III
Authors: Hasenbos M. , Van Egmond J. , Gielen M. , Crul J. F.
Published: January 2009

One hundred and twenty‐nine patients were subjected to three different types of thoracic operations. The patients were randomly allocated to balanced intravenous anaesthesia including i.v. nicomorphine during surgery and epidural nicomorphine post‐operatively (epidural group, n = 58) or to balanced intravenous anaesthesia without i.v. opiates but with high thoracic epidural regional block during the operation and with post‐operative intramuscular nicomorphine (intramuscular group, n = 71). Post‐operative nicomorphine was only given at the request of the patients, and as frequently as needed to obtain satisfactory pain relief. Patients in the epidural group were given nicomorphine exclusively by epidural injection. Post‐operatively, both groups (i.m. and epidural) obtained effective and rapid onset of analgesia, but the pain assessments by the patient and the medical team favoured the epidural group. The requirements of nicomorphine over a period of 3 days were significantly lower in the epidural group 42 mg (s.d.= 18) versus 92 mg (s.d. = 33) in the intramuscular group. Significantly fewer pulmonary complications were observed in the epidural group: 7 atelectases compared to 27 in the intramuscular group. The epidural group showed no signs of ventilatory depression in spite of a catheter inserted at the T3‐T4 level.
Hemodynamic effects of high frequency ventilation superimposed on intermittent positive pressure ventilation in dogs
Authors: Mogensen T. , Eliasen K. , Nielsen L. , Gravesen H. , Rygård H. , Andersen J. B.
Published: January 2009

The hemodynamic effects of high frequency ventilation (HFV) superimposed on intermittent positive pressure ventilation (IPPV) in seven dogs before and after thrombin infusion were investigated. HFV was superimposed on a Servo 900 B ventilator by a Siemens Elema HFV prototype unit. Mean arterial blood pressure, heart rate, central venous pressure, pulmonary artery pressure, cardiac output, right and left ventricular pressures, pleural pressure, arterial blood gases, and right and left ventricular ejection fractions were recorded. Measurements were done during IPPV alone and during HFV superimposed on IPPV. The HFV frequencies were 5, 15, and 20 Hz at a constant minute volume of 51. When HFV was started, the IPPV minute volume was reduced to one third of the initial volume. No significant changes in the measured parameters were observed during the different ventilatory modes either before or after thrombin infusion which doubled the pulmonary vascular resistance. It is concluded that high frequency ventilation superimposed on IPPV might be a ventilatory mode that offers cardiovascular stability and reduces the risk of barotrauma.
Plasma concentrations of prilocaine and lidocaine and methaemoglobin formation in infants after epicutaneous application of a 5% lidocaineprilocaine cream (EMLA)
Authors: Engberg G. , Danielson K. , Henneberg S. , Nilsson A.
Published: January 2009

The aim of the study was to measure the plasma levels of lidocaine and prilocaine after dermal application of EMLA in infants and to evaluate whether this procedure increases the levels of methaemoglobin (Met‐Hb). Two groups of infants, 3–6 (n=12) and 6–12 months (n=10) of age, were studied. In total, 2 ml of EMLA was applied to 4 × 4 cm of skin surface for 4 h and blood samples for detection of Met‐Hb and plasma levels of local anaesthetics were taken at 0, 2, 4 and 8 h after the application. After removal of the cream the infants were operated mainly for minor procedures under general anaesthesia. The plasma concentrations of lidocaine and prilocaine were in all cases below toxic levels and there were only minor increases in Met‐Hb in a few infants. In conclusion, EMLA can be used safely in infants above 3 months of age provided that the recommendations with regard to dose, application area and time are followed. The use of EMLA in smaller infants and in children taking other Met‐Hb‐inducing drugs needs further evaluation.
Antagonism of diazepam‐induced sedative effects by Ro 15–1788 in patients after surgery under lumbar epidural block
Authors: Dodgson M. S. , Skeie B. , Emhjellen S. , Wickstrøm E. , Steen P. A.
Published: January 2009

The aim of this study was to assess the efficacy of Ro 15–1788 and a placebo in reversing diazepam‐induced effects after surgery under epidural block, and to evaluate the local tolerance and general safety of Ro15‐1788. Fifty‐seven patients were sedated with diazepam for surgery under epidural anaesthesia. Antagonism of diazepam‐induced effects by Ro15‐1788 was investigated postoperatively in a double‐blind placebo‐controlled trial. The patient's subjective assessment of mood rating, an objective test of performance, a test for amnesia, and vital signs were recorded for up to 300 min after administration of the trial drug. No significant differences between the two groups were observed for mood rating, amnesia, or vital signs. The Ro15‐1788 group showed a significant improvement in the performance test up to 120 min after administration of the drug. There was no evidence of reaction at the injection site.
Pretreatment with atracurium: the influence on neuromuscular transmission and pulmonary function
Authors: Howardy‐Hansen P. , Moller J. , Hansen B.
Published: January 2009

The influence of pretreatment with atracurium on neuromuscular transmission was evaluated in 60 healthy volunteers using train‐of‐four (TOF) nerve stimulation and measurement of respiratory rate (RR), vital capacity (VC), inspiratory force (IF), and peak expiratory flow (PEF). The subjects were randomly allocated to one of four groups: Group I received atracurium 0.02 mg/kg, Group II 0.03 mg/kg, Group III 0.04 mg/ kg, and Group IV atracurium 0.05 mg/kg. TOF ratio decreased significantly in all four groups. There was, however, no difference between the groups after injection. PEF decreased significantly in all four groups, VC decreased in Groups I and IV, and RF increased significantly only in Group IV. Three subjects (5%) had shallow, frequent respiration; however, none needed respiratory support. The majority of the volunteers experienced blurring of vision and heavy eyelids: 82% and 67%, respectively. All subjects were able to sustain head lift for 10 s or more after atracurium. Careful observation of respiration is necessary, especially when using the higher doses of atracurium.
The effect of thoracic epidural analgesia on respiratory function after cholecystectomy
Authors: Hendolin H. , Lahtinen J. , Länsimies E. , Tuppurainen T. , Partanen K.
Published: January 2009

To assess the effect of thoracic epidural analgesia (TEA) on postoperative respiratory function and pulmonary complications, a prospective randomized trial was conducted in patients undergoing cholecystectomy. One hundred patients were allocated to TEA (n = 30), TEA + general anaesthesia (TEA + GA) (n = 30), or general anaesthesia (GA) (n = 40) groups. Respiratory function was analysed by measuring forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), functional residual capacity (FRC), total lung capacity (TLC), peak expiratory flow (PEF) in the supine and sitting postures, and arterial blood gases. Postoperative pulmonary complications were carefully documented. TEA significantly prevented the postoperative deterioration of respiratory function as compared with general anaesthesia. FVC, FEV1 and PEF decreased by 20% in patients receiving TEA, in contrast to 55% in patients after GA on the day of operation. This improvement continued until the 2nd day after operation, when FVC, FEV1 and PEF and their recovery rates were equal in all groups. In the sitting posture the preoperative FVC, FEV1 and PEF were about 10% greater than in the supine position. After operation, this difference was further increased. The preoperative difference of 27% in FRC between the sitting and supine postures was maintained after operation. Pao2 decreased by 0.8 kPa after TEA, by 1.5 kPa after TEA + GA with the lowest value on the 2nd postoperative day and by 1.5 kPa after GA, with the lowest value immediately after operation. Simultaneous hypercarbia indicated hypoventilation, which may have contributed to impaired respiratory function on the following days. There were fewer atelectases after TEA, 8/30 (27%), as compared with TEA + GA, 12/30 (40%,) (P<0.1), and GA 20/40 (50%) (P<0.05). FRC before operation and FVC after operation were significantly less in patients who developed postoperative pulmonary complications, indicating a role of preoperative pulmonary disease as an aetiological factor.
Effect of ipratropium bromide aerosol on respiratory function in patients under ventilator treatment
Authors: Wegener T. , Wretman S. , Sandhagen B. , Nyström S. O.
Published: January 2009

Twenty patients, 36–78 years old, with a history of chronic obstructive lung disease, and immediately after operation mostly for cardiac disease, were treated with ipratropium bromide (IB, 15 cases) or placebo (5 cases). A metered dose inhaler with a new adapter was used during postoperative ventilator treatment. In the IB group the heart rate did not change, but the inspiratory resistance decreased and the arterial oxygen tension increased. This is considered to indicate an effect not only on large but also on small airways, or an improvement of the ventilation/perfusion relationship. The investigation also demonstrated the practical usefulness of the new adapter.
Ketamine monoanaesthesia for major surgery in epidermolysis bullosa
Authors: Idvali J.
Published: January 2009

A case report is presented of a patient with recessive dystrophic epidermolysis bullosa, who required anaesthesia for a major plastic surgery operation. The special anaesthetic problems are discussed, and ketamine monoanaesthesia is advocated when muscle relaxation is unnecessary. Glycopyrrolate was (bund to be an excellent antisialogenic agent.
Changes in respiratory pattern after repeated doses of diazepam and midazolam in healthy subjects
Authors: Berggren L. , Eriksson I. , Mollenholt P. , Sunzel M.
Published: January 2009

Changes in respiratory pattern and arterial Pco2 after three repeated intravenous sedative doses of midazolam 0.05 mg/kg or diazepam 0.15 mg/kg were studied in eight healthy male volunteers in a randomized double‐blind crossover design. In order to reduce the influence of the measuring equipment, we utilized a noninvasive computerized technique to measure respiratory variables. Both drugs caused equal changes in breathing pattern with a decrease in tidal volume, an increase in respiratory rate and an unaltered minute ventilation. These alterations in breathing pattern were associated with Co2 retention. Respiratory changes were mainly induced by the first injection of either drug. Despite increased plasma drug concentrations, subsequent doses did not cause further changes in respiratory variables except for an increase in Pco2 after the second dose of midazolam. The clinical significance of these changes in Paco2 in otherwise healthy individuals is probably limited. The duration of the subjective sensation of sedation was longer after diazepam than after midazolam.