bluuebunny/crossref_metadata_2025 huggingface dataset:
Atelectasis during anaesthesia and in the postoperative period
Authors: STRANDBERG Å. , TOKICS L. , BRISMAR B. , LUNDQUIST H. , HEDENSTIERNA G.
Published: January 2009

Transverse sections of lung tissue were studied in patients by computerized tomography during anaesthesia and in the postoperative period. Eight patients were studied during intravenous (thiopentone) and six during inhalational (halothane) anaesthesia. The latter patients were studied during both spontaneous and mechanical ventilation. Five of the patients who underwent surgery for inguinal hernia and five patients in whom laparotomy was performed were studied 1 h and 24 h postoperatively. No patient showed any lung changes while awake preoperatively, and all patients developed dependent, crest‐shaped lung densities within 5–10 min of anaesthesia. The densities comprised 3.4% of the lung volume in the caudal (basal) 5 cm of the lung tissue. No significant differences in the size and distribution of the densities were noted between spontaneous breathing and mechanical ventilation during anaesthesia, or between intravenous and inhalational anaesthesia. The densities remained in nine of ten patients 1 h postoperatively, and they remained in five of ten patients 24 h after anaesthesia. The densities are considered to be compression atelectases which may develop as a result of relaxation of the diaphragm. They may be important contributors to postoperative pulmonary complications.
Effect of adenosine‐induced controlled hypotension on canine myocardial performance, blood flow and metabolism
Authors: ÖWALL A. , SOLLEVI A. , RUDEHILL A. , SYLVÉN C.
Published: January 2009

The effect of adenosine‐induced controlled hypotension (CH) on myocardial performance, blood flow, and metabolism was studied in nine pentobarbital‐anaesthetized, open‐chest dogs. Adenosine was continuously infused i. v. (0.69 0.06 and 1.36 0.11 mg/kg/min) at two stepwise increased rates (12–14 min‐periods) in order to induce approximately 20 and 40% reduction of the mean arterial pressure (MAP 62 4 and 43 1 mmHg, respectively). The reduction of MAP was associated with decreases in heart rate (6 2%,P<0.05 and 21 4%,P<0.01), left intraventricular systolic pressure (14 3%,P<0.01 and 32 3%,P<0.01), left ventricular end‐diastolic pressure (23 9%,P<0.05 and 42 9%,P<0.01) and ventricular intramyocardial systolic pressure (15 6% n. s. and 27 6%,P<0.01). The rate pressure product was markedly reduced by 49 3% (P<0.01) at the highest infusion rate. The mean coronary vein pressure (20.3 2.8 mmHg) was unaffected by the adenosine infusion. The systolic pressure time index (SPTI) was decreased by 33 3% (P<0.01) during the highest infusion rate of adenosine, while the diastolic perfusion time index (DPTI) was 15.4 2.2 mmHg s and remained unchanged. The DPTI:SPTI ratio increased by 40 13% (P<0.05), suggesting a sufficient endocardial oxygen supply. The coronary sinus blood flow (96 7 ml/min) increased by 40 16% (P<0.05), while the myocardial oxygen uptake (7.2 0.8 ml/min) decreased by 28 5% (P<0.01) during the highest infusion rate. The myocardial lactate uptake and the left ventricular subendocardial ECG (n = 4) were unchanged during CH. In conclusion, adenosine‐induced CH in the canine open‐chest preparation reduced myocardial work as well as oxygen uptake, and increased the total myocardial blood flow. No signs of regional myocardial ischaemia appeared, as judged from the unaffected myocardial lactate uptake and left ventricular sub‐endocardial ECG.
Effects of anaesthesia and surgery on serum opsonic capacity
Authors: PERTTILÄ J. , LILIUS E. ‐M. , SALO M.
Published: January 2009

Several factors of immune response are affected by anaesthesia and surgery. Opsonization as a phase of the phagocytic process was studied in ten patients undergoing cholecystectomy under balanced anaesthesia with thiopentone, suxamethonium, pancuronium, N2O+O2, fentanyl, dehydrobenzperidol and enflurane. The luminol‐dependent chemiluminescence responses were depressed at the end of surgery in phagocytosis of patient‐serum‐opsonized zymosan and Bordetella pertussis (P<0.05). The responses to Bordetella pertussis were already depressed after the period of presurgery anaesthesia (P<0.05). The responses returned to preinduction values by the third postoperative day. Since the decreases could only be observed with diluted serum and there were no infectious complications in the patients, the serum opsonic capacity was considered clinically sufficient during and after anaesthesia and surgery.
Effects of increases in the inspired oxygen fraction on brain surface oxygen pressure fields in pig and man
Authors: Eintrei C. , Lund N.
Published: January 2009

In six patients undergoing neurosurgical operation, brain surface oxygen pressure was studied during an increase of the inspired oxygen fraction (Fio2). The eight‐channel oxygen surface electrode (MDO‐electrode) was placed directly on the brain cortex. Fio2 was increased to four levels, from baseline level 0.21 to 0.3, 0.5, 0.7 and 1.0, respectively. During these four stages and Fio2 0.21, brain surface oxygen pressure (Pto2) was measured. The physiological variables such as blood pressure, Paco2, pH and temperature were stable throughout the study. The results are presented as mean values ± s.d. and a Pto2 histogram for each Fio2‐level. Already at an Fio2 of 0.3 (at a Pao2 of 16.3 ± 3.4 kPa) scattered histograms were seen in five of six patients. A scattered histogram indicates disturbed microcirculation. At the Fio2 levels of 0.5, 0.7 and 1.0, all histograms were scattered. The Pto2 values did not increase proportionally to Pao2 at Fio2 levels 0.3, 0.5 or 0.7. But at Fio2 1.0 four patients had normal mean Pto2 values and two patients very high mean Pto2 values. It is possible that the four patients with normal Pto2 values succeeded in regulating the cerebral microcirculation as a response to the high Fio2 leading to a high Pao2 (60.1 ± 6.4 kPa). The same study was initially done on six pigs in which the regional cerebral blood flow (rCBF) was also measured. MDO‐electrode measurements at different Fio2‐levels gave the same results as in the patients. rCBF decreased when Fio2 was increased.
Malignant hyperthermia: clinical course and metabolic changes in two patients
Authors: Rutberg H. , Häkanson E.
Published: January 2009

Two cases of malignant hyperthermia (MH) are presented. One patient was treated symptomatically for the first 6 h until she was given dantrolene. Her clinical course was complicated and the catecholamine and cortisol concentrations were still elevated 24 h after start of treatment. In the second patient an early diagnosis was made and treatment promptly instituted. Only minor endocrine‐metabolic changes were seen in this patient. However, in spite of the early successful treatment with dantrolene the MH reaction recurred 12 h after the initial symptoms. These two cases demonstrate the importance of early treatment including dantrolene. Successful treatment with dantrolene does not, however, preclude a recurrence of MH, and thus subsequent doses of dantrolene should be given.
Respiratory effects of high thoracic epidural anaesthesia
Authors: Sundberg A. , Wattwil M. , Arvill A.
Published: January 2009

The respiratory effects of high thoracic epidural anaesthesia (TEA) were studied in nine healthy volunteers by means of spirometry, nitrogen single‐breath test and flow‐volume loop. After the baseline measurements an epidural catheter was inserted at T4 level, and 5 ml of 0.5% bupivacaine were injected. This volume led to sensory block within dermatomes T1‐T5. Total lung capacity, vital capacity and inspiratory capacity decreased slightly but significantly during TEA. Expiratory reserve volume was not affected. Maximal inspiratory flow at 50% VC decreased 24%. Maximal expiratory (low at 75% VC and peak expiratory flow were not changed. N2 difference during a constant flow rate of 0.5 l/s and forced expiratory volume in l s were not changed, which indicates that there were no changes of bronchial tone. The respiratory effects of high TEA in this study were caused by the motor block of the intercostal muscles.
A study of halothane‐diethyl ether azeotrope and the Oxford miniature vaporizer
Authors: Bengtsson M. , Malmqvist L.‐Å. , Löfström J. B.
Published: January 2009

The performances of an Oxford miniature vaporizer (OMV) and a Fluotec Mark III vaporizer filled with an azeotropic mixture of halothane and diethyl ether were studied. Gas concentrations were estimated using an EMMA gas analyser and a MIRAN spectrophotometer. Calibration tables for both vaporizers were derived. In a small clinical series with air as the carrier gas, to which a small amount of oxygen was added, the azeotrope was found to be a satisfactory anaesthetic agent, giving a short awakening time and an almost pain‐free postoperative course.
The effects of triazolam on cerebral blood flow and metabolism in the dog
Authors: Roald O. K. , Steen P. A. , Stangland K. , Michenfelder J. D.
Published: January 2009

The new benzodiazepine triazolam was given to six initially awake dogs maintained with spinal anaesthesia and mechanical ventilation. Both cerebral blood flow (CBF) and cerebral metabolic rate for O2(CMRo2) were significantly reduced after the initial dose of 0.1 mgx kg‐1triazolam, and the EEG changed from an awake to a sleep pattern in less than 20 s. CMRO2was gradually reduced with increasing doses of triazolam (0.3, 1.0, 10.0 and 30.0 mgx kg‐1) to 76% of control after the final 30 mgx kg‐1dose. CBF did not decrease further after the initial dose, and the addition of N2O after the final dose did not cause any significant change in CBF or CMRO2. The dogs were hemodynamically stable during the study. Small increases in brain lactate and pyruvate levels, but not in the L/P ratio were the only significant changes in brain metabolite levels. Triazolam appears to be a safe and rapidly acting induction agent in the dog.
Thrombosis following percutaneous radial artery cannulation
Authors: Cederholm I. , Sørensen J. , Carlsson C.
Published: January 2009

A prospective study of the arterial supply of the hand was carried out in 100 ICU patients after cannulation of the radial artery. Patency of the radial artery was checked using a reversed Allen's test and Doppler ultrasonic technique. Furthermore, radial artery angiography was carried out in 15 patients with suspect thrombosis, and the artery was examined by microscopy in four patients at autopsy. Signs of thrombosis, Allen's test and Doppler technique, were found in 33/100 patients. In 10/15 angiograms a thrombosis was visualized, and in 3/4 patients at autopsy a thrombosis was found. The incidence of thrombosis was not correlated to sex, age, size of artery (judged by wrist circumference), cannulation technique or the presence of hypotension. It did, however, correlate to the presence of haematoma at the puncture site. After removal of the cannula recanalisation occurred soon in the majority of cases.
Densities in dependent lung regions during anaesthesia: atelectasis or fluid accumulation?
Authors: Strandberg Å. , Hedenstierna G. , Tokics L. , Lundquist H. , Brismar B.
Published: January 2009

In previous studies with computed tomography (CT) prior to and during general anaesthesia, we found that densities developed in dependent parts of the lungs immediately after induction of anaesthesia in all examined patients. It was suggested that the densities were atelectases created by compression of lung tissue, but an alternative explanation could be accumulation of extravascular fluid in the lung tissue and /or in the pleural space. In the present study the nature of the densities was analysed in further detail. Injections of contrast medium into the pleural space revealed that the densities were located in the lung tissue and not in the pleural space. By injecting contrast medium intravenously and repeating the CT scanning over a 2‐min period the passage of contrast through the major vessels and the lung densities could be studied. The transit time of the contrast medium was of the same magnitude in the densities and the major lung vessels. This indicates that there were no regions with an increased amount of extravascular fluid to delay the contrast passage. These findings oppose the idea of fluid accumulation as the cause of the densities, while atelectasis remains the most plausible explanation.
Blood flow in the radial artery before and after arterial puncture
Authors: Noreng M. F.
Published: January 2009

A study was carried out on seven patients to determine whether sub‐clinical changes occurred in the blood flow in the radial artery following uncomplicated arterial puncture. An ultrasonic technique was used, and it was demonstrated that no changes take place in the blood flow, measured 15 min after puncture.
Variation in spread of analgesia and loss of temperature discrimination during intermittent postoperative epidural bupivacaine administration
Authors: Bigler D. , Hjortsø N. c. , Kehlet H.
Published: January 2009

The proximal‐distal and bilateral extent of analgesia and loss of temperature discrimination were assessed during the initial 34.5 h after major abdominal surgery in ten patients receiving intermittent epidural bupivacaine injections according to a fixed dose regimen, Segmental spread of loss of temperature discrimination was invariably larger than analgesia at all times. During the later postoperative period (24–34 h) a pronounced intra‐individual variation in both proximal‐distal and bilateral spread of analgesia was observed despite identical epidural injections of bupivacaine. This variation in extent of analgesia was observed during injections of both 0.5% and 0.25% bupivacaine. The explanation of this observation is unknown but it may be shifts in catheter position, a variable disposition of the local anaesthetic agent or changes in the epidural space rather than tachyphylaxis.
On‐line measurement of gas‐exchange during cardiac surgery
Authors: Fletcher R. , Malmkvist G. , Niklason L. , Jonson B.
Published: January 2009

This paper describes an on‐line system for continuously monitoring expired CO2 during controlled ventilation. Signals from a Servo ventilator 900B or C and a CO2 Analyzer 930 are processed and corrected by the computer to produce a CO2 single breath test (SBT‐CO2). This is the tracing of expired CO2 concentration or fraction against expired volume, from which the computer calculates the airway deadspace (VDaw). If a value for arterial PCO2 is supplied, the computer will calculate the physiological deadspace (VDphys) and the alveolar deadspace (VDalv) for each breath. The system was used to make measurements at four stages during coronary artery by‐pass grafting in 13 male patients. When the sternum was opened there was a 32% increase in VDaw, and the physiological deadspace fraction therefore increased. There were reductions in VDaw after extra‐corporeal circulation and again after sternal suture. By the end of surgery, the alveolar deadspace fraction had increased significantly. VDaw at this stage was smaller than pre‐operatively, and so there was no net change in the physiological deadspace fraction at the end of surgery. Arterial Po2 was, however, reduced at this stage.
Effects of prolonged surgical trauma on the extravascular lung water and central blood volume in the dog
Authors: Frostell C. , Blomqvist H. , Hedenstierna G. , Pieper R. , Halbig I.
Published: January 2009

Extravascular lung water (EVLW) and central blood volume (CBV) were measured in 13 dogs with a double‐indicator dilution technique (dye‐cold), the indicators being detected intravascularly. Animals in a control group (n = 5) were mechanically ventilated for 8–15 h after baseline measurements. Another group of animals (n = 8) were subjected to extensive lymph duct cannulations, including a thoracoabdominal incision, and the dogs were followed for 8 to 18 h postoperatively. All dogs (n= 13) then received a dose of oleic acid intravenously in order to create lung damage. A positive fluid balance was maintained throughout the experiment. Basal EVLW was 8.8 ml/kg (n= 13) (similar in both groups), and did not change significantly in either group before oleic acid. Basal CBV was 18.5 ml/kg (n=13); it increased (P<0.05) in the control group and decreased (P<0.05) in the surgery group during a 8–15‐h period. EVLW was doubled (P<0.001) and CBV decreased slightly 2 h after oleic acid administration. The lung damage was similar in both groups. and was accompanied by increased pulmonary vascular pressures and marked reductions in arterial oxygen tension and thoracic compliance. The findings suggest that an earlier proposed dog model for the simultaneous measurement of EVLW and lymph flow can be used in long‐term studies on lung fluid balance.
Prevention of peroperative hypothermia in abdominal surgery
Authors: Kristensen G. , Guldager H. , Gravesen H.
Published: January 2009

It is important to reduce or prevent heat loss during anaesthesia, especially in patients with restricted cardiopulmonary reserves. To test a specially developed esophageal thermal tube (GK‐esophageal thermal tube) for this purpose, 33 patients were randomly divided into two groups: Group A were given heat transferred to the central core during operation, using the GK‐tube with circulating 41.7°C warm water. Group B received no active warming. All patients were scheduled for major abdominal operation. In both groups there was a temperature fall in the induction phase. In Group B the temperature continued to fall slowly during operation, resulting in a median end‐temperature of 34.9°C. In Group A the temperature rose slowly after induction of heat via the tube, resulting in a median end‐temperature of 36.8°C in this actively warmed group. The temperature difference is significant (P <0.001). The median operating time was 3h 30 min in both groups. After 2 h of anaesthesia the median temperature in Group A was 36.1°C and in Group B 35.0°C. This difference is also significant (P<0.001). The described method was easy to use and without complications. We recommend this method to prevent peroperative hypothermia in all patients suspected to have limited cardiopulmonary reserves. The possible hazards and how to avoid these are described.
Alfentanil v. isoflurane for outpatient arthroscopy
Authors: Zuurmond W. W. A. , Leeuwen L. van
Published: January 2009

Alfentanil by continuous intravenous infusion and isoflurane have been compared as anaesthetic agents for outpatient arthroscopy. In 42 patients, divided at random into two groups, anaesthesia was induced with methohexitone and vecuronium bromide, and, after intubation, maintained with nitrous oxide 66% in oxygen combined with alfentanil or isoflurane. Alfentanil was given before intubation (1 mg), as a loading dose before starting surgery (50 μg kg‐1) and by a continuous infusion at a rate of 1 μg kg‐1min‐1. Isoflurane was given in a concentration of 0.9% as a maintenance dose. Awakening from anaesthesia was morc rapid with alfentanil than with isoflurane. Recovery tests were applied in the recovery room. Both anarsrhetic techniques provided satisfactory anaesthesia and rapid recovery. All patients but one were content with the anaesthesia. The patients who received isoflurane scored better in the recovery tests in the first 3 h, but after 3 h there was no difference between the groups. The alfentanil group showed a higher incidence of nausea and/or vomiting: 45% compared to 14% in the isoflurane group.
Reversal of the cerebral effects of diazepam in the dog by the benzodiazepine antagonist 1015–1788
Authors: Roald O. K. , Steen P. A. , Milde J. H. , Michenfelder J. D.
Published: January 2009

In six dogs initially anesthetized with halothane‐N2O‐O2 for surgery and maintained during the experiment with high spinal anesthesia and local infiltration, diazepam 3.0 mg.kg‐1 converted the EEG from an awake to a sleep pattern. This was accompanied by a significant 21% reduction in cerebral metabolic ratc for oxygen (CMRo2) and a 15% reduction in cerebral blood flow (CBF). Substituting nitrous oxide 70% for nitrogen had no additional cerebral effects. The benzodiazepine antagonist Ro15–1788, 2 mg, completely reversed the effects of diazepam on the EEG, CMRo2 and CBF. Cerebral biopsies taken at the end of the study revealed modest but significant decreases in ATP and the energy charge along with increases in AMP, lactate and lactatelpyruvate (L/P) ratio. These changes are unexplained and suggest a possible disturbance in oxidative phosphorylation produced by Ro15–1788 preceded by diazepam.
Intubating conditions after vecuronium and atracurium given in divided doses (the priming technique)
Authors: Mirakhur R. K. , Very G. G. La , Gibson F. M. , Clarke R. S. J.
Published: January 2009

Intubating conditions have been assessed at 60 s following administration of vecuronium 0.1 mg kg‐1 or atracurium 0.5 mg kg‐1 given either as a single dose after induction of anaesthesia with thiopentone or in divided doses; vecuronium 0.015 mg kg‐l followed 4 or 6 min later by 0.085 mg kg‐1, or atracurium 0.075 mg kg‐1 followed 4 or 6 min later by 0.425 mg kg‐1. In the divided dose groups the smaller initial (priming) dose was given prior to induction of anaesthesia. Onset and duration of clinical relaxation were assessed using a peripheral nerve stimulator. The intubating conditions at 60 s improved significantly. with the use of relaxants in divided doses being acceptable in 80 and 70% of patients, respectively, with vecuronium and atracurium, but the conditions are not as good as those commonly found using suxamethvniuin. Priming at 6 min has no advantage over priming at 4 min. The onset of complete block was accelerated with priming. but the difference was not significant. The duration of clinical relaxation of vecuronium was significantly prolonged by giving it in divided doses. Unpleasant awareness of muscle weakness was observed in 15 patients, requiring early induction of anaesthesia in five of them.
Liver susceptibility to ischaemia in spontaneously hypertensive rats
Authors: Wennberg E. , Hagberg H. , Haljamäe H.
Published: January 2009

Blood loss has previously been shown to be more detrimental for spontaneously hypertensive (SHR) than for normotensive Wistar‐Kyoto (WKY) rats. To evaluate whether this decreased tolerance to blood loss is due to disturbances in circulatory control or to alterations in cellular function caused by the hypertensive disease, SHR and WKY were subjected to complete liver ischaemia. During a 45‐min period of ischaemia as well as after 4 h of reflow, the liver content of ATP, glycogen, glucose and lactate was determined. Liver ATP decreased to 15% and liver glycogen to 30% of initial levels, while liver glucose increased 6‐fold and liver lactate 13‐fold during the ischaemic period in both SHR and WKY. Following 4 h of reflow, KIP was restored to 11.5± 1.7 μmol × g protein‐1 (56% of initial level) in SHR and to 15.2 ± 1.3 (76%) in WRY. The levels of lactate and glucose returned to control levels after the reflow period while the glycogen stores were further depleted in SHR as well as WKY. No difference between SHR and WKY in cellular metabolic function during the ischaemic period could thus he demonstrated, and the postischaemic recovery was not significantly different. It is concluded that hypertensive disease does not seem to change the ischacmic tolerance of liver cells to any considerable extent.
Airway lesions caused by prolonged intubation with standard and with anatomically shaped tracheal tubes. A post‐mortem study
Authors: Eckerbom B. , Lindholm C.‐E. , Alexopoulos C.
Published: January 2009

Two groups of patients intubated for long periods were examined post mortein. In Group A (22 patients) the mean duration of intubation was 4.0 days and in Group B (19 patients) 5.7 days. The mean for the two groups was 4.8 days. In Group A a conventional endotracheal tube was used, and in Group B an anatomically shaped tube. Both tubes had cuffs of the intermediate‐volume, low‐pressure type. The larynx and trachea, from the epiglottis to the bifurcation, were removed in one piece at autopsy and the inner surfare was photographed. The photographs were magnified and from these the size and estimated depth of any lesions were recorded. In the arytenoid and tracheal regions no significant difference was found between the two groups. In the cricoid region, on the other hand, the outcome was significantly more favourable following use of the anatomically shaped tube.
Pharmacokinetics of intravenous, intrathecal and epidural morphine and fentanyl in the goat
Authors: Andersen H. B. , Christensen B. , Findlay J. W. A. , Jansen J. A.
Published: January 2009

Intrathecal and epidural catheters and an intravenous cannula were inserted in 10 goats. After administration of either morphine 4 mg, intravenously, 1 mg intrathecally or 4 and 8 mg epidurally. or fentanyl 0.1 mg intravenously, 0.05 mg intrathecally or 0.1 and 0.2 mg epidurally, venous blood and CSP were sampled at 2, 5, 10. 15, 30 min and 1, 2, 4, 6, 8 and 24 h. The concentrations of the drugs were measured by radioimmunoassay. After administration of intravenous morphine the plasma concentrarion‐time curve fitted a 3‐compartment model (body clearance = 84 ±23 ml/min/kg, mean ± s.d., N = 5), while after fentanyl the plasma concentration‐time curve was best described by a 2‐compartment model (body clearance = 3.9–5.8 ml/min/kg, N = 3)). After intrathecal injection the elimination rates of the opioids from CSF were 0.3 to 2.0 and 0.6 to 2.4 ml/h/kg for morphine and fentanyl, respectively (N = 3). The time to reach maximum CSF concentration after epidural administration was 0.22 ±0.14 h for morphine (N = 6) and 0.22 ±0.13 11 for fentanyl (N = 8). In the same goat the CSF availability was 2.3 and 11.3% for morphine and 0.8 and 3.3%, for fentanyl following epidural administration of the low and high doses, respectively. After cpidural administration, morphine and fentanyl are absorbed into CSF at the same rate but the relative amount of drug absorbed may be higher for morphine than fentanyl. Bulk flow is supposed to be the principal mechanism of opioid elimination from CSF.
Effects of epidural analgesia on scalp‐recorded somatosensory evoked potentials to posterior tibial nerve stimulation
Authors: Saugbjerg P. , Asoh T. , Lund C. , Kühl V. , Kehlet H.
Published: January 2009

The effect of epidural analgesia with plain bupivacaine 0.5% on somatosensory evoked potentids (SEP) to electrical stimulation of the posterior tibial nerve was examined in six patients. Epidural analgesia significantly increased onset time and latencies of the early components in SEP, while the amplitudes deercased. These results suggest that SEP may he valuable in the objective evaluation of possible differential neurual effects of local anaesthetic agents following epidural or intrathecal administration.
Gastric volume and pH in children for emergency surgery
Authors: Schurizek B. A. , Rybro L. , Bøggild‐Madsen N. B. , Juhl B.
Published: January 2009

The volume and pH of gastric contents aspirated prior to anaesthesia were measured in 101 children admitted for emergency surgery. The children were aged between 3 months and 15 years. If we define potential patients at risk by means of the volume and pH of the gastric contents, then 50.0% of the children were at risk of aspiration into the lungs. The number of patients at risk was higher in children aged between 6 and 10 years. There was almost the same risk in the groups with abdominal‐, urogenital‐, and orthopacdic diseases, while the number of patients at risk was less in the group with superficial lesions. The length of fasting time in the child considerably influenced the volume of gastric contents in emergency surgical cases. It is concluded that in children admitted for emergency surgery there is a risk of aspiration of gastric contents into the lungs. The risk is reduced by preanaesthetic fasting. All children admitted for emergency surgery must be carefully evaluated prior to anaesthesia with special reference to gastric aspiration.
Flunitrazepam‐fentanyl‐induced sedation and analgesia for bone marrow aspiration and needle biopsy in children
Authors: Maunuksela E.‐L. , Rajantie J. , Siimes M. A.
Published: January 2009

We describe the use of flunitrazepam and fentanyl to produce sedation and analgesia, as an alternative to general anesthesia, for 96 children with malignancies or hematologic diseases, undergoing 122 hone marrow examinations (BME). In 82 cases there was no reaction to the puncture. Most children had complete amnesia and only two remembered some pain. In 10% the sedation and analgesia was considered inadequate and barbiturate was given; seven out of these 12 children were under the age of 3 years. During 117 procedures the children maintained adequate spontaneous ventilation; in five cases the ventilation was assisted. In 13 cases there were minor side‐effects including drowsiness and nausea. One child had a short apnea after the procedure.
Pulmonary ventilation, CO2 response and inspiratory drive in spontaneously breathing young infants during halothane anaesthesia
Authors: Olson A. K. , Lindahl S. G. E.
Published: January 2009

Pulmonary ventilation, CO2 response and inspiratory drive were studied during halothane anaesthesia prior to surgery in 13 spontaneously breathing infants less than 6 months of age. Pneumotachography and capnography were used. Airway and oesophageal pressures were measured and occlusion tests were performed at functional residual capacity. Measurements were made before and during 8 min of 4% CO2 stimulation. Inspiratory drive increased significantly (P<0.001) at CO2 stimulation. This resulted in increased minute ventilation (P<0.001) and tidal volume (P<0.001) while respiratory rate was unchanged. As VDBohr/VT ratios were the same, the net effect was increased alveolar ventilation (P<0.001). CO2 elimination was unpredictable in these young infants and decreased during CO2 stimulation (P<0.05), while mean end‐tidal CO2 concentration only increased from 5.2 to 6.3% (P<0.001). The ventilatory response to 4% CO2 could therefore be deemed to be adequate during the short period (8 min) of CO2 breathing. However, this was achieved at the cost of increased work as witnessed by the increased ratio between minute ventilation and CO2 elimination (P<0.01). Stabilisation of end‐tidal CO2 concentrations during CO2 inhalation took only 10 s while the maximal increase in ventilation volumes was not achieved until after 150 s. It is concluded that young spontaneously breathing infants anaesthetized with halothane (MAC 1.3) have an increased respiratory drive with greater tidal volumes during CO2 stimulations. Respiratory timing, dynamic compliance and total pulmonary resistance were, however, uninfluenced by 4% CO2 stimulation. Increased monitoring of CO2 output in anaesthetized infants is suggested.
Enflurane inhibits muscle fasciculations caused by suxamethonium in children
Authors: Lindgren L. , Saarnivaara L.
Published: January 2009

Eighty‐three children with a mean age of 2.7 years were anaesthetized with either thiopental 5 mg/kg followed by suxamethonium 1.5 mg/kg i.v. or with enflurane 5 vol% in 70% nitrous oxide in oxygen via a face mask. In the enflurane group, venepuncture was performed when the children were unconscious, 1.8 ±0.05 (s.e.) min after the start of anaesthesia. After enflurane, suxamethonium 1, 1.5 or 2 mg/kg was administered i.v. for endotracheal intubation. The incidence and duration of muscle fasriculations after suxamethonium were significantly lower (P<0.01) in the enflurane groups than in the thiopental group. The fasciculation index was significantly lower (P<0.01) in the enflurane groups than in the thiopental group. In the enflurane groups, intubating conditions were better (P<0.05) in the children treated with suxamethonium 2 mg/kg than in those treated with suxamethonium 1 mg/kg.
A trial of povidone‐iodine for prevention of contamination of intravenous cannulae
Authors: Jakobsen C. J. B. , Grabe N. , Damm M. D.
Published: January 2009

A prospective randomized study of 227 intravenous cannulae was undertaken to evaluate the effects of two different skin disinfectants before intravenous cannulation. Patients were divided into two groups. In one povidone‐iodine was used as disinfectant while in the other 70% isopropylalcohol was used. Intraluminal contamination rates, colony counts and organisms isolated are presented. We found no correlation between use of cannulae sideport and contamination. It was found that povidone‐iodine as a skin disinfectant reduced the intraluminal contamination from 22 to 7.25% (P<0.01).
The calculation of left ventricular stroke work index
Authors: Settergren G.
Published: January 2009

The relation between left ventricular mean systolic pressure (LVSP) determined by planimetric integration and systolic and diastolic pressure measured in a peripheral artery (SAP and DAP) was calculated using data published by Ross & Braunwald in 1964. The relation was LVSP = SAP‐0.32 ± 0.06 (s.d.) × (SAP‐DAP). The formula SAP‐0.32 (SAP‐DAP) was used to calculated LVSP, and the correlation betwem measured and calculated LVSP was found to be 0.91 (P< 0.001). It is concluded that LVSP can be calculated with reasonable accuracy from measurements of arterial pressure in patients without aortic stenosis. At present three different formulas are in use for the calculation of left ventricular stroke work index (LVSWI). The pressure work is defined as SAP, LVSP or mean arterial pressure minus mean pulmonary capillary wedge pressure or left ventricular end diastolic pressure. This makes comparisons between different studies with respect to LVSWI difficult or impossible.
The relationship between cerebral metabolic rate of oxygen and cerebral blood flow in the acute phase of head injury
Authors: Cold G. E.
Published: January 2009

In 20 comatose patients (Glasgow coma scale ≤6 at admission) with severe head injury, the cerebral metabolic rate of oxygen (CMRo2) was calculated as the product of the hemispheric cerebral blood flow (CBF) and the arterio‐venous oxygen content difference (AVDo2). The hemispheric CBF was calculated by the intracarotid 133xenon washout method by stochastic analysis as the average of 16 regions, and the measurements were performed within 3 weeks after the acute trauma. Generally no significant correlation (P<0.05) between CMRo2 and CBF was found, either in the total number of paired observations, in studies of hyperaemia defined as CBF≥30 ml 100 g‐1 min‐1; or in studies with reduced flow (CBF<30 ml 100 g‐1 min‐1). However, in about 50% of patients subjected to repeated studies within days, CBF was positively correlated to CMRo2, and this correlation was observed independently of the CBF value. Hyperaemia was associated with a significant decrease in AVDo2, a significant increase in both absolute and relative CO2 reactivity, and a significant increase in ventricular fluid pH; but not to an increase in intraventricular pressure, mean arterial blood pressure or significant changes in ventricular fluid lactate or lactatelpyruvate ratio.
Continuous transcutaneous oxygen measurement: reproducibility and trace analysis in healthy adults
Authors: Swift A. C. , Downham D. Y.
Published: January 2009

One hundred and fourteen transcutaneous oxygen traces were obtained from 46 adults using a mass spectrometer. Such traces usually rise to a plateau about which they fluctuate. To estimate the plateau level, here called the asymptote, two models are described ‐ a time‐series model and a growth model. If yt is the trace measurement at time t, for the time‐series model

yt+l = m + α(yt‐m)+ε1, and for the growth model

dyt/dt = β(m‐yt),

where parameters α and β represent the rate of approach to the asymptote m. Least squares estimates of these parameters were determined for every trace. For every trace, the estimated asymptotes are similar for both models but the other parameters show less agreement. Considering the traces for each person in pairs, each trace pair is allocated to one of four groups according as the traces were recorded on the same or different sites and on the same or different days. The correlation coefficient (r) between the estimated asymptotes is greatest for traces recorded on the same site and day (r>0.94, P< 0.001) and least for traces from different sites and days (r>0.71, P<0.001). The time series estimates of the asymptotr arc more credible than the growth model.
Pulmonary function, extravascular lung water and chest radiography in a porcine model of adult respiratory distress syndrome
Authors: Forsgren P. , Wegenius G. , Modig J.
Published: January 2009

To study the pathophysiology and the value of chest radiography in the diagnosis of early adult respiratory distress syndrome spontaneously air‐breathing pigs under ketamine anaesthesia were investigated. Five control animals received physiological saline and showed no notable changes in physiological or radiological data. Eleven animals were infused i.v. with E. coli endotoxin over 6 h. The pulmonary dysfunction in the endotoxin animals was characterized by an early increase in venous admixture with hypoxaemia and a peak increase in pulmonary vascular resistance at 0.5 h after start of endotoxin infusion. Subsequently there was a tendency towards a restitution to baseline physiology, but from 3 h onwards a “second wave” of pulmonary dysfunction developed in addition to an increase in extravascular lung water. No significant correlation (r = 0.44) existed between the increase in extravascular lung water and venous admixture. The increase in calculated pulmonary microvascular pressure correlated significantly (r = 0.77) with the increase in extravascular lung water. Radiographic signs of pulmonary oedema were sparse. Thus, only three of 11 animals displayed increased density on chest radiography indicative of pulmonary oedema.
Central venous access via the external jugular vein in cardiovascular surgery
Authors: Berthelsen P. , Hansen B. , Howardy‐Hansen P. , Mølller J.
Published: January 2009

In 115 consecutive adult patients scheduled for cardiovascular surgery, 150 catheterizations of the innominate or superior caval veins via an external jugular vein were attempted. The Seldinger technique was employed. In 99 (96–100)% of the attempts a straight, J‐modified straight or a J‐wire could be passed into the central venous system. One hundred and forty‐six (97 (93–99)%) of the subsequent catheter insertions were successful. Thirty‐five patients had bilateral catheter insertions. Both sides proved to be equally suitable. Six anesthetists participated in the study and the longest catheterization time was 16 min. All catheterization procedures were uncomplicated.
Work practices relating to intubation in operating rooms in Sweden
Authors: Mehta S. , Mickiewicz M.
Published: January 2009

A survey into the current usage of tracheal tubes in operating rooms was carried out in Swcdrn by scnding a questionnaire to anaesthetists in charge of anaesthetic departments in 90 arute hospitals, which included seven teaching hospitals. The object was to determine how far the recent advances in tube, cuff design and material had influenced the attitudes and work practices of anaesthetists. Fifty‐eight replies were recorded (a 64.4% response rate). All teaching hospitals and the majority of other hospitals favoured tubes with high‐volume, low‐pressure cuffs. Most hospitals used size 9 orotracheal tubes in adult male and size 8 in adult female patients. Seventy‐one per cent of teaching hospitals used both local anaesthetic jelly for lubricating tubes and topical laryngeal spray prior to intubation. Nasal decongestants were used by only 14.2% of teaching hospitals prior to nasal intubation. Over three‐fourths of the hospitals were in favour of inflating the cuff to no‐leak ventilation. Just over half of non‐teaching hospital and two‐thirds of teaching hospital monitored intracuff pressure.
Anaesthetic problems in Hurler‐Scheie syndrome. Report of two cases
Authors: Sjøgren P. , Pedersen T.
Published: January 2009

Hurler‐Scheie syndrome is an intermediate form of mucopolysaccharidosis. Affected patients characterstically present in infancy with serious abnormalities including the upper airways and the lungs. We present two patients with Hurler‐Scheie syndrome and describe their anaesthetic management. One caw was complicated by difficult endotracheal intubation and postoperative pneumonia. The second casr was successfully miinagtd using spinal anaesthesia and mild sedation.
Adenosine in the inhibition of diazepam sedationby aminophylline
Authors: Niemand D. , Martinell S. , Arvidsson S. , Ekström‐Jodal B. , Svedmyr N.
Published: January 2009

Aminophylline in a low dose has been shown to reverse diazepam sedation. The present investigation was performed as a double‐blind study to compare the effects of aminophylline and enprofylline on deep diazepam sedation after surgery. Enprofylline is a xanthine derivative with anti‐asthmatic effect but, in contrast to aminophylline, enprofylline has very weak adenosine antagonistic properties. A comparison should make it possible to evaluate if adenosine is involved in the observed effects. Twenty male patients undergoing transurethral surgery in spinal anaesthesia were given diazepam during surgery to maintain a state of deep sedation. Postoperatively aminophylline or enprofylline was given from coded ampoules in equipotrnt anti‐asthmatic doses (4.5 or 1.5 mg/kg). The degree of sedation was assessed prior to and after the injections. A difference between the groups was obvious. Patients given aminophylline showed rapid reversal of sedation, persisting throughout the 2‐h observation period. Following enprofylline, a markedly slower reversal of sedation was observed. It is likely that aminophylline antagonises diazepam sedation by blocking adenosine receptors. Some clinical implications are outlined.
Measurement of pulmonary capillary blood flow by a nitrous oxide rebreathing technique
Authors: Stokke T. , Burchardi H. , Angerer H. , Hensel I.
Published: January 2009

Measurements of pulmonary capillary blood flow by a nitrous oxide rebreathing technique (Qn2o) werr performed in 21 anesthetized and artificially ventilated minipigs with normal lungs and in nine minipigs with thrombin‐induced (75–150 U kg‐1 h‐1) lung pathology. Qn2O was calculated with the Hook‐Meyer‐formula and compared to cardiac output measurements (thermodilution, Qt, or direct Fick's principle, Qfick). The coefficient of variation in double QN2O measurements was 0.05. If the tidal volume to dead space ratio (Vd/Vt) is normal, the nitrous oxide method works well, but when the efficacy of ventilatioti worsens, this gas uptake method fails to detect the circulation of the poorly ventilated parts of the lung. The mean ratio Qn2o/Qfick in pigs with normal lungs (58 measurements) was 1.00 ± 0.10 (mean ± s.d.). During thrombin infusion, the mean ratio Qn2O/Qt was 0.84 ± 0.17 (n = 49). After corrections for shunt perfusion (Qs), the mean ratio Qn2o/(Qt—Qs) was 0.89 ± 0.17 (n = 49). Qn2o/(Qt—Qs) decreased with increasing Vd/Vt. In measurements during thrombin infusion with VD/VT <0.33, the mean ratio Qn2o/(Qt‐Qs) was 0.97 ± 0.11 (n = 21), with a Vd/Vt between 0.33 and 0.44, the mean ratio Qn2o/(Qt—Qs) was 0.90 ± 0.08 (n = 20), and with a Vd/Vt ± 20.45, this ratio was 0.62 ± 0.18 (n = 8). In the presence of only moderate functional inhomogeneities, this noninvasive rebreathing method will offer reliable data on pulmonary perfusion.
Premedication for day‐case surgery: double‐blind comparison of ketobemidone + dimethylaminodiphenylbuten (A‐29) and morphine + scopolamine
Authors: Reder J. C. , van der Linden J. , Breivik H.
Published: January 2009

A double‐blind comparison of the effect of Ketogana (ketobemidone and A‐29, an anticholincrgic and spasmolytic agent) and morphine + scopolamine as premedication was performed in 113 women admitted for abortion and in 114 women admitted for gynaecological dilatation and curettage. Anaesthesia was thiopentone and nitrous oxide and oxygen, occasionally supplemented with enflurane. It was found that 1 ml morphine + scopolamine (10 mg + 0.4 mg) was more sedative than 1 ml ketogan (ketobemidonr 5 mg + A‐29 25 mg). After ketogan there was less nausea and dryness of the mouth before induction of anaesthesia than after morphine + scopolamine. Ketogan had the same tranquillizing effect but less hypnotic effect preoperatively than morphine + scopolamine. During the 3‐h postoperative observation period the patients premedicated with ketogan woke up significantly sooner and had more pain than those given morphine + scopolamine. More patients required postoperative antiemetics in the ketogan‐prernedicated group than in the morphine + scopolamine‐premedicated group.
Slowing of the heart during hypotension in major abdominal surgery
Authors: Røsgaard S. , Secher N. H.
Published: January 2009

Heart rate (HR) and mean arterial blood pressure (MBP) were studied during abdomino‐perineal resections of the rectum under neurolept anesthesia in order to observe HR deviations due to hypovolcmic hypotcnsion. Of the 65 patients followed, 18 developed a systolic BP under 100 mmHg. Their blood loss (37 ± 9 ml/kg, mean ± s.e. mean) was higher than that of the normotensive control group (20 ± 2 ml/kg, P<0.01), the urine production lower (8±1 versus 10 ± J ml/kg, P<0.01) and blood transfusions amounted to 40 ± 8 versus 24 ± 2 ml/kg (P<0.01). In the hypotensive patients a decrease in MBP from 108 ± 3 to 94 ± 3 mmHg was accompanied by a simultaneous increase in HR from 81 ± 3 91 ± J beats/min (P<0.05). However, during the hypotensive incident where the MBP averaged 69 ± 4 mmHg, HR decreased temporarily to 75 ± J beats/ min (P<0.001). After MBP was restored to 94 ± 3 mmHg using volume repletion, HR increased to 95 ± 3 beats/min (P<0.001). The results demonstrated a temporary slowing of HR in anesthetized, bleeding and hypotensive patients.
The non‐steroidal anti‐inflammatory agent, indoprofen, does not protect against hydrochloric acid induced lung injury in the rat
Authors: Royston D. , Fleming J. S. , Krausz T.
Published: January 2009

The effects of pulmonary instillation of hydrochloric acid on solute flux from the lung (measured as the clearance of 99mTcDTPA) together with an index of oedema formation (the ratio of lung wet weight to lung dry weight) was measured in rats. There was a significant increase in 99mTcDTPA clearance (P <0.001) and also in lung wet:dry weight ratio (P<0.01) 4—5 h following acid challenge. There was no difference in the effects of challenge with acid of pH1 and pH2. In addition, intravenous injection of indoprofen (20mg/ kg) a non‐steroidal anti‐inflammatory agent failed to produce any beneficial effect on the variables under study when given after acid (pH2) challenge. There was also histological evidence of an influx and sequestration of granulocytes into the lung. Despite this, the plasma concentration of thiobarbituric acid reactive material (used as an index of cell‐derived, oxidant‐free radical production) was significantly reduced in all acid‐treated groups. These data show that hydrochloric acid will initiate a severe inflammatory response In the lung of the rat and that the non‐steroidal anti‐inflammatory agent indoprofen when given after the injury produced no evidence of a beneficial effect on this inflammatory response.