bluuebunny/crossref_metadata_2025 huggingface dataset:
Gastric intramucosal pH and blood lactate in severe sepsis
Authors: Joynt G. M. , Lipman J. , Gomersall C. D. , Tan I. , Scribante J.
Published: January 2004

We prospectively investigated the effect of conventional resuscitation on gastric intramucosal pH and lactate over 5 days in a group of patients with newly diagnosed severe sepsis. Lactate and gastric intramucosal pH were measured on entry into the study, as soon as resuscitation end points were met, eight hourly for 48 h and daily for 5 days. Sixteen of 18 patients had a low gastric intramucosal pH (mean (SD) 7.17 (0.12)) at the time of diagnosis of severe sepsis. At no time did gastric intramucosal pH or lactate distinguish between shocked and nonshocked patients. Lactate distinguished survivors from nonsurvivors over time (p = 0.02). Gastric intramucosal pH did not distinguish survivors from nonsurvivors over time (p = 0.72). At 48 h lactate was lower in survivors (p < 0.01) and gastric intramucosal pH higher in survivors (p < 0.05). Receiver operating characteristic curves at this time indicate that lactate is a better predictor of survival. It is likely, based on the inability of gastric intramucosal pH to distinguish survivors from nonsurvivors until 48 h, that it is not possible to use this measurement to guide resuscitation in patients who are severely ill and who have gastric intramucosal acidosis.
A comparison of intercuff and single cuff techniques of intravenous regional anaesthesia using 0.5% prilocaine mixed with technetium 99m‐labelled BRIDA
Authors: Risdall J. E. , Young P. C. , Jones D. A. , Hett D. A.
Published: January 2004

Intravenous regional anaesthesia of the upper limb is a widely used technique first described by Bier in 1908. The exact site of action of injected local anaesthetic has not been determined. We have performed intravenous regional anaesthesia on volunteers using prilocaine mixed with technetium 99m‐labelled 2,4,6 trimethyl‐3‐bromo iminodiacetic acid. Two different techniques of intravenous regional anaesthesia (the ‘normal’ cuff and the intercuff techniques) were combined with gamma camera tracking of the radiolabel to determine the site of local anaesthetic action. The onset of action was similar for both techniques. The local anaesthetic was mainly retained in the antecubital fossa in both techniques but in the ‘normal’ technique, the local anaesthetic subsequently showed some retrograde spread. This would suggest that the main site of action of local anaesthetic used for intravenous regional anaesthesia is the larger nerves in the vicinity of the antecubital fossa.
Intravenous magnesium sulphate in the management of refractory bronchospasm in a ventilated asthmatic
Authors: Mills R. , Leadbeater M. , Ravalia A.
Published: January 2004

A 25‐year‐old man with severe asthma was admitted to intensive care for mechanical ventilation. Conventional treatment with beta agonists, theophylline and steroids resulted in little improvement. Magnesium sulphate was used to reduce bronchospasm and airway pressure. This produced considerable clinical improvement, which facilitated weaning from mechanical ventilation.
Nerve stimulators for nerve location — are they all the same?A study of stimulator performance
Authors: Barthram C. N.
Published: January 2004

This study set out to examine the nerve stimulators available in one trust hospital. Six different models were identified (Braun Stimuplex, Braun Stimuplex DIG, Digistim 3, Digistim 3 Plus, Regional Master Corporation Nerve Finder, Bard 750 Digital) and the output characteristics were measured for each stimulator using a twin beam calibrated storage oscilloscope. Target current output values from 0.3 mA to 3 mA and load resistances from 560 Ω to 10 kΩ were selected to model the normal ranges of operating current and skin electrode — needle impedance when performing regional anaesthesia. Only half of the stimulators tested were able to complete the test and deliver a target current to ± 20% accuracy. The variation in performance of nerve stimulators means that for a safe and successful nerve block it is important for the operator to be aware of the design and functional limitations of any stimulator being used in clinical practice.
A comparison of the Invos 3100 and the Critikon 2020 near‐infrared spectrophotometers as monitors of cerebral oxygenation
Authors: McKeating E. G. , Monjardino J. R. , Signorini D. F. , Souter M. J. , Andrews P. J. D.
Published: January 2004

Assessment of cerebral oxygenation using near‐infrared spectroscopy in intensive care is increasing. We compared the ability of the Invos 3100 and the Critikon 2020 monitors to produce stable and consistent readings of regional cerebral oxygen saturation in resting volunteers. Failure to obtain any stable reading with the Critikon occurred in eight out of 18 subjects (44.4%) and with the Invos in three out of 15 subjects (20%). The Critikon showed a significantly higher failure rate in male subjects (p = 0.0011). Differences in recorded values of cerebral oxygen saturation (Critikon − Invos) ranged from −4.7% to 12.6% and were significantly related to the average saturation level (p < 0.0001). The within‐monitor variability was significantly higher for the Invos (p = 0.0124). Neither monitor is able to give stable and consistent readings over time, particularly in male subjects. The unacceptably high failure rate of the recently introduced Critikon 2020 will limit or prevent its clinical use.
A survey of how British obstetric anaesthetists test regional anaesthesia before Caesarean section
Authors: Bourne T. M. , DeMelo A. E. , Bastianpillai B. A. , May A. E.
Published: January 2004

We surveyed members of the Obstetric Anaesthetists Association asking how they tested regional blocks prior to Caesarean section. A large proportion of these anaesthetists appear to test their blocks inadequately. Temperature sensation was the most common sensory modality tested (64%) and 79% of those who tested for temperature sensation used an ethyl chloride spray.
Epidural dextran 40 patch for postdural puncture headache
Authors: Reynvoet M. E. J. , Cosaert P. A. J. M. , Desmet M. F. R. , Plasschaert S. M.
Published: January 2004

We report a case where two consecutive blood patches failed to relieve postdural puncture headache and hearing loss following inadvertent dural puncture. Initial conservative therapy with analgesics, fluids and later two blood patches had no effect and the patient's symptoms only resolved after an epidural dextran 40 patch performed 8 weeks after the dural tap. Two months later, the patient is still asymptomatic
Additional inspiratory resistance imposed by the laryngeal mask airway: in vitro versus in vivo comparison
Authors: Righini E. R. , Marangoni E. , Volta C. A. , Alvisi R. , Bortolazzi S. , Gritti G.
Published: January 2004

The present study was designed: (a) to compare the additional inspiratory laryngeal mask airway (LMA) resistance measured in vitro during simulated ventilation and in vivo in five anaesthetised and mechanically ventilated patients; and (b) to evaluate the resistive pressure drop along the length of the LMA. After the differential pressure across the mask was measured, the pressure–flow relationship was characterised by Rohrer's equation and in vitro and in vivo resistance was calculated. Thereafter, the distal pressure measuring point was moved along the length of the LMA and differential pressure was measured at each point under in vitro and in vivo conditions. Values for resistance were approximately twice as great in vivo as those obtained in vitro, with most of the resistive pressure drop occurring across the vertical bars, especially when measured in vivo. We conclude that in vivo positioning of the LMA significantly increases resistance because of the configurational changes occurring when the LMA is in situ.
Intra‐ocular pressure changes following laryngeal mask airway insertion: a comparative study
Authors: Whitford A. M. , Hone S. W. , O'Hare B. , Magner J. , Eustace P.
Published: January 2004

We compared the effects of the Brain laryngeal mask airway with a tracheal tube on intra‐ocular pressure. Propofol was used as induction agent and atracurium as relaxant. Twenty‐six patients with normal intra‐ocular pressure undergoing cataract surgery were randomly allocated to two groups. Group A (n = 13) had a laryngeal mask airway inserted and Group B (n = 13) had a tracheal tube inserted. Intra‐ocular pressure was measured just before insertion of the airway, 20 s after insertion and at 2 min. In the laryngeal mask airway group there were no significant changes in mean intra‐ocular pressure. In the tracheal tube group there was a significant rise in mean intra‐ocular pressure at 20 s (p = 0.0056) which returned to pre‐insertion levels at 2 min. We conclude that the laryngeal mask airway continues to have advantages over the tracheal tube for ophthalmic surgery despite the use of propofol and atracurium as anaesthetic agents.
Fatal hepatic necrosis after isoflurane anaesthesia
Authors: Weitz J. , Kienle P. , Böhrer H. , Hofmann W. , Theilmann L. , Otto G.
Published: January 2004

Several halogenated anaesthetic agents have been associated with hepatotoxicity. We report a case of fulminant, fatal hepatic necrosis after uneventful isoflurane anaesthesia in a patient without previous liver disease, who may have been sensitised by previous exposure to enflurane. Although no anti‐trifluoroacetyl antibodies could be detected in the patient's serum, isoflurane hepatotoxicity seems very likely to be the reason for fulminant hepatic failure in this patient.
A new hinged tip laryngoscope
Authors: Benham S. W. , Gale L.
Published: January 2004

The McCoy laryngoscope undoubtedly improves the view of the vocal cords during difficult tracheal intubation. An inherent design problem with the McCoy blade is the need to relax the grip on the laryngoscope handle at the point when stability is most necessary. A new hinged tip blade is described which is operated by a button mechanism on a secondary handle that runs adjacent to the standard handle. This modification offers the possibility of better stability and ease of manipulation whilst maintaining all the benefits of the McCoy blade.
A dual technique for identification of the epidural space
Authors: Jacob S. , Tierney E.
Published: January 2004

A method of identifying the epidural space is described in which the traditional loss of resistance to air technique is combined with amplification of the sound made by the epidural needle as it traverses the interspinous ligament and the ligamentum flavum and then enters the epidural space. The method retains all the advantages of the loss of resistance to air technique whilst, in addition, the auditory amplification gives a slightly earlier warning of entry into the epidural space. The apparatus necessary is readily available and the technique is easy to use. In addition to being useful in difficult epidurals, the technique would also be an excellent teaching aid.
Prevention of hypotension during spinal anaesthesia for Caesarean section: ephedrine infusion versus fluid preload
Authors: Chan W. S. , Irwin M. G. , Tong W. N. , Lam Y. H.
Published: January 2004

We compared the efficacy of prophylactic ephedrine infusion over fluid preloading in prevention of maternal hypotension during spinal anaesthesia for Caesarean section. Forty‐six women undergoing elective Caesarean section at term were allocated randomly to receive either intravenous fluid preloading with Hartmann's solution 20 ml.kg−1 (fluid group) or prophylactic intravenous ephedrine 0.25 mgkg−1 (ephedrine group). Moderate hypotension was defined as ≥ 20% reduction in systolic blood pressure and severe hypotension as ≥ 30% reduction in systolic blood pressure. Maternal uterine circulation was measured using Doppler ultrasound in 11 parturients before and after spinal anaesthesia. There was a lower incidence of severe hypotension in the ephedrine group compared with the fluid group (35% vs. 65%, p = 0.04), although the incidence of moderate hypotension was similar. Mean umbilical venous pH was higher in the ephedrine group than in the fluid group (7.33 vs. 7.29, p = 0.02) and the number of patients shivering was lower in the ephedrine group (2 vs. 9, p = 0.02). No difference was found between pre‐ and postspinal uterine artery pulsatility indices in either group. We conclude that prophylactic ephedrine infusion alone is at least as good as fluid preload alone in combating the hypotension associated with spinal anaesthesia for Caesarean section.
Cardiac rupture during electroconvulsive therapy
Authors: Ali P. B. , Tidmarsh M. D.
Published: January 2004

A 57‐year‐old man with recurrent depression, resistant to drug therapy, was scheduled for a course of eight electroconvulsive therapy treatments. The patient had undergone seven treatments without incident over the previous 3 weeks. Immediately following the final treatment, the patient suffered cardiovascular collapse, culminating in cardiac arrest with electromechanical dissociation. Despite resuscitative measures, the patient died. Post‐mortem examination found the cause of death to be cardiac tamponade, secondary to cardiac rupture.
Taking a ‘drugs’ history
Authors: Hocking G. , DeMello W. F.
Published: January 2004

A simple, anonymous questionnaire was used to examine the depth of drug history taken from patients by a group of junior doctors. The results showed that most who replied restricted their history to prescription medicines and smoking. We feel that this is no longer sufficient and that a drug history should be expanded to include substances such as recreational drugs and over‐the‐counter preparations. If an allergy is reported, detailed questioning about its nature is also important since the term is often used by patients when a true allergy does in fact not exist. We present a mnemonic which can be used as an aide memoire to the various areas of importance.
The effect of co‐induction with midazolam upon recovery from propofol infusion anaesthesia
Authors: Tighe K. E. , Warner J. A.
Published: January 2004

Forty‐eight patients undergoing day‐case anaesthesia were asked to complete pre‐ and postoperative tests of psychomotor function in order to study the influence of co‐induction with midazolam in conjunction with propofol/alfentanil anaesthesia on postoperative psychomotor recovery. The study was placebo controlled and double blind with patients receiving either 0.03 mgkg−1 of midazolam or saline 2 min before induction of anaesthesia with propofol and alfentanil. Patients who underwent co‐induction with midazolam had significantly impaired concentration and rapidity of response but improved accuracy and vigilance when compared with those who received saline. The study confirmed that co‐induction with a subanaesthetic dose of midazolam reduced the induction dose of propofol by up to 50%. We conclude that co‐induction with midazolam reduces psychomotor recovery in the immediate postoperative phase following propofol infusion anaesthesia.
The need for basic sciences in the understanding and practice of anaesthesia
Authors: Burnstein R. M. , Jeevaratnam R. D. , Jones J. G.
Published: January 2004

We conducted a survey using an unstructured, then a structured, questionnaire to determine the attitudes of 78 postfellowship anaesthetists to the Basic Sciences component of the part I examination for the FRCA. Seventy‐two per cent replied. These anaesthetists felt that about 65% of the basic science syllabus was essential to the understanding and practice of everyday anaesthesia, but there was varying opinion as to the importance of specific topics. Cardiovascular, respiratory, central nervous system and renal physiology were all regarded as essential, as was the pharmacology of anaesthetic drugs. Topics regarded as irrelevant included biochemistry, endocrinology, membrane theory and immunology. Paradoxically, there were many topics which anaesthetists regarded as essential but on which they were unable to give a tutorial. There was little difference between the responses of consultants and trainees. This survey may help to identify a core syllabus on which the majority of anaesthetists agree but also suggests that the current syllabus is overloaded with detail that has no place in clinical practice.
The contribution of extracranial blood oxygenation on near‐infrared spectroscopy during carotid thrombendarterectomy
Authors: Grubhofer G. , Lassnigg A. , Manlik F. , Marx E. , Trubel W. , Hiesmayr M.
Published: January 2004

To determine the contribution of extracranial oxygenation on regional cerebral oxygenation measured by an Invos 3100 near‐infrared spectrometer, we measured oxygenation in blood drawn from both the facial vein (draining substantially blood from forehead areas) and the jugular venous bulb. There was no correlation between regional cerebral oxygenation and facial vein oxygenation (p = 0.35) but there was a significant correlation between regional cerebral oxygenation and jugular venous bulb oxygenation (p = 0.027). Linear regression analysis predicted a 3.6% change in regional oxygenation for every 10% change in jugular venous bulb oxygenation. We showed that extracranial tissue oxygenation had a negligible influence on the values recorded using near‐infrared spectroscopy. Individual changes in jugular venous bulb oxygenation were poorly reflected. Data obtained by this near‐infrared spectroscopy device are an unreliable guide to the adequacy of cerebral oxygenation.
Effect of nebulised lignocaine on the quality of induction of anaesthesia in cigarette smokers
Authors: Caranza R. , Raphael J. H. , Nandwani N. , Langton J. A.
Published: January 2004

We have assessed the effect of nebulised lignocaine, given pre‐operatively, upon the quality of induction of anaesthesia in cigarette smokers. Seventy‐five patients were studied in a double‐blind randomised fashion, receiving a nebuliser of either 4 ml 0.9% NaCl or 4 ml 4% lignocaine. All patients received a standardised anaesthetic consisting of thiopentone followed by progressive increments of enflurane. Thirty‐three out of 38 patients (87%) who received nebulised lignocaine had induction without adverse events, compared with 25 out of 37 patients (68%) in the nebulised saline group (Chi‐squared test p < 0.05). We conclude that the use of nebulised lignocaine, administered pre‐operatively, improves the quality of induction of anaesthesia in cigarette smokers.
Behavioural changes in children following day‐case surgery: a 4‐week follow‐up of 551 children
Authors: Kotiniemi L. H. , Ryhänen P. T. , Moilanen I. K.
Published: January 2004

The purpose of this prospective multicentre survey was to evaluate the occurrence and the type of changes in children's behaviour during the first 4 weeks following the day of surgery, and to assess the significance of some patient‐related factors on the incidence. Pre‐ and postoperative questionnaires were completed by the parents of 551 children aged 4 months to 13.4 years in five hospitals incorporating nine operative units in Northern Finland. The overall incidence of problematical behavioural changes was 47% and that of beneficial changes 17%. Problematical changes were most common in the 1.0 to 2.9 year olds and the incidence decreased significantly from 46% on the day of the operation to 9% 4 weeks later (p < 0.0001). Predictors by multiple logistic regression analysis were age, mild pain at home following surgery, severe pain and a previous bad experience of health care which had adversely affected the attitude of the child towards doctors or nurses. Hospital influenced playing was a significant factor 3 and 4 weeks after the operation. By the 4th week, beneficial and problematical changes were equally common (9%). Gender, previous operations and experience of repeated paracenteses (for treatment of middle ear infection) did not have a significant effect on the incidence. Pain on the day of the operation predicted the occurrence of behavioural problems up to the 4th week, 2–4 weeks longer than the duration of pain itself. The results emphasise the importance of effective prevention of postoperative pain as well as the importance of avoiding unpleasant experiences in all contacts children have with health care. Playing could perhaps be used to help children cope with a short hospital experience.
Postoperative symptoms at home following day‐case surgery in children: a multicentre survey of 551 children
Authors: Kotiniemi L. H. , Ryhänen P. T. , Valanne J. , Jokela R. , Mustonen A. , Poukkula E.
Published: January 2004

The incidence and duration of postoperative symptoms in children at home following day‐case anaesthesia and surgery was evaluated using a questionnaire completed by parents of 551 children aged 4 months to 13.4 years (mean 3.8 years). They also evaluated the instructions given in hospital for care at home. The incidence of all symptoms was highest at home on the day of the operation. No postoperative symptoms were reported in 79 (14%) children. The incidence of pain was 56% and the only significant predictor was the type of operation, tonsillectomy being the most problematic (mild pain in 38% and severe in 25%; pain lasted 7 days or longer in 33%). Analgesics were given to 78% of all the children reported to have pain on the day of the operation, to 60% the next day and later to 58%; 19 (3%) children were given more than two doses per day. The instructions given in hospital for the treatment of pain were considered inadequate by 12% of parents. Postoperative nausea and vomiting occurred in 13% of children. Predictors by multiple stepwise logistic regression analysis were emetic symptoms in hospital, pain at home, age > 5 years and administration of postoperative opioid (pethidine or fentanyl). Opioid given during anaesthesia (fentanyl or alfentanil) did not increase the incidence. Emetic symptoms were most common after tonsillectomy (31%). The highest incidences of emetic symptoms (37%), sedation (96%) and dizziness (41%) occurred in children who had been given fentanyl for postoperative pain. Undertreatment of nausea in hospital was evident as only two children had received anti‐emetics, even though 61 were reported to have emetic symptoms. Administration of effective anti‐emetics should be encouraged, as emetic symptoms in hospital were the most significant predictor of nausea and vomiting at home. Treatment of pain at home and instructions for treatment of pain need to be improved.
Magnesium sulphate for control of spasms in severe tetanusCan we avoid sedation and artificial ventilation?
Authors: Attygalle D. , Rodrigo N.
Published: January 2004

A prospective pilot study was undertaken to investigate the ability of magnesium sulphate to control the spasms of severe tetanus without the need for sedation and artificial ventilation. All eight patients admitted with severe tetanus to our intensive care unit within the last year were given magnesium sulphate intravenously as a 5‐g loading dose followed by an infusion of 2–3 g h−1. The infusion rate was increased to control spasms while retaining the patella tendon reflex, which proved a valid guide to avoid overdose. Spasms were effectively controlled and serum magnesium concentrations were maintained within the therapeutic range. Spontaneous ventilation was adequate, ventilatory support being required only for the management of lung pathology. There was no evidence of cardiovascular instability due to sympathetic over activity. No supplementary sedation was required for the control of spasms or autonomic dysfunction during magnesium therapy. We conclude that magnesium sulphate can be used as the sole agent for the control of spasms in tetanus without the need for sedation and artificial ventilation.
Acute superior vena caval syndrome with airway obstruction following elective mediastinoscopy
Authors: Power C. K. , Buggy D. , Keogh J.
Published: January 2004

A 47‐year‐old female patient had a subclinical superior vena caval syndrome which developed into the ‘full blown’ acute condition when she was placed into the left lateral position after mediastinoscopy. She developed airway obstruction requiring urgent re‐intubation and subsequent admission to the intensive care unit. This subclinical condition might have been suspected pre‐operatively if closer attention had been paid to the history, physical examination and review of the computerised axial tomography scan: she had a history of intermittent dyspnoea, wheeze and cough which was worse on waking and improved as the day progressed, she had a positive Pemberton's sign and the computerised axial tomography scan showed that the lesion was encroaching on the superior vena cava.
A comparison of the effects of tramadol and morphine on gastric emptying in man
Authors: Murphy D. B. , Sutton A. , Prescott L. F. , Murphy M. B.
Published: January 2004

In a previous study using an electrical bioimpedance technique and the paracetamol absorption test, we demonstrated that 0.09 mgkg−1 of morphine delayed gastric emptying in healthy human volunteers. The aim of this study was to investigate whether analgesic doses of tramadol would cause a delay in gastric emptying similar to conventional opioids. Using the same volunteers and techniques as in our previous study, placebo or tramadol (1 mgkg−1) was given in a randomised, double‐blinded, cross‐over placebo‐controlled study. Gastric emptying was measured concurrently by a noninvasive epigastric bioimpedance technique and by the paracetamol absorption test. After the ingestion of 500 ml of deionised water plus paracetamol 1.5 g, the mean (SEM) time taken for gastric volume to decrease to 50% (t0.5) was recorded. No difference in gastric emptying rates (t0.5) between placebo, 7.7 (1 min), and tramadol, 9.5 (2 min), was noted. In our previous study, morphine prolonged t0.5 to 21 (3) min (p < 0.03). The maximum concentration and area under the curve of serum paracetamol concentrations following morphine were significantly different from placebo (p < 0.05) and tramadol (p < 0.05). We conclude that tramadol at a dose of 1 mgkg−1 does not delay gastric emptying in humans.
The influence of age upon opioid analgesic use in the patient‐controlled analgesia (PCA) environment
Authors: Woodhouse A. , Mather L. E.
Published: January 2004

It is often asserted that older patients are more sensitive to opioid analgesics than younger patients but experimental evidence for this assertion remains sparse. Two studies were conducted investigating the relationship between age and opioid analgesic use in the patient‐controlled analgesia environment. In study I, the relationship was analysed subsequent to our publication of a study investigating patients' responses to opioid use with patient‐controlled analgesia. Fifty‐five postoperative patients, stratified into ‘older’ and ‘younger’ patients by median age, received morphine or pethidine or fentanyl patient‐controlled analgesia. A strong inverse relationship was found between age and fentanyl and morphine use but not between age and pethidine use. Study II was a retrospective study of the medical records of 199 patient‐controlled analgesia patients who had received morphine or pethidine patient‐controlled analgesia; there were insufficient patients who had used fentanyl for a reasonable sample. There was a difference in morphine use with the younger patients using significantly more morphine than the older patients (> 60 years). Findings were less clear for patients receiving pethidine but there was an inverse correlation between age and pethidine use as well. Overall, the findings of these two studies supported the common clinical belief that older patients require less opioids than younger patients.
Mechanical obstruction in the anaesthesia delivery‐system mimicking severe bronchospasm
Authors: Aarhus D. , Søreide E. , Holst‐Larsen H.
Published: January 2004

We present a case where mechanical obstruction in the anaesthesia delivery system caused by plastic wrapping from a filter was misinterpreted as severe bronchospasm. The patient suffered severe hypoxia before the problem was solved by using a free‐standing self‐expanding ventilation bag. This near‐fatal incident emphasises the importance of thorough equipment checking routines, rapid troubleshooting and how equipment failure may be misinterpreted as a medical complication. It also shows how transparent container material can become a medical hazard.
The effect of pre‐operative administration of bupivacaine compared with its postoperative use
Authors: Campbell W. I. , Kendrick R. W. , Ramsay‐Baggs P. , McCaughey W.
Published: January 2004

Eighty patients undergoing lower third molar surgery under general anaesthesia were assigned to one of two groups to receive local anaesthetic blockade either 10 min prior to surgery or after surgery just before leaving the operating theatre. Patients in both groups received the local anaesthetic block whilst unconscious. Pain was assessed using visual analogue scales at 6 h and 1, 3 and 6 days after surgery. A McGill Pain Questionnaire was also completed on the morning following surgery. At no time was it possible to detect any significant difference in pain between the two groups. The administration of local anaesthesia prior to starting surgery does not appear to have any advantage over its postoperative administration in patients undergoing this type of surgery. The local anaesthetic, however, does provide excellent analgesia during the first few hours following surgery.
The effect of a toothguard on the difficulty of intubation
Authors: Brosnan C. , Radford P.
Published: January 2004

Dental damage is the most common reason for complaints against anaesthetists. The purpose of this study was to investigate the common belief that the use of a toothguard at the time of intubation causes intubation to be more difficult. We studied 80 patients, half of whom were intubated with a toothguard in situ and the other half intubated without a toothguard. The time taken from mouth opening to successful passage of the tracheal tube through the vocal cords was measured. In the toothguard group, the recorded time also included the time taken to insert the toothguard. The median time to intubation in the group with a toothguard was 24 s and the median time to intubation in the group without a toothguard was 17 s. The difference of 7 s in the time to intubation was statistically significant (p =0.0003). As the recorded times also included the time taken to insert the toothguard, we do not regard this result to be clinically significant and believe that anaesthetists should think carefully before disregarding this simple protective device.
A comparison of 2% and 1% formulations of propofol for the induction and maintenance of anaesthesia in surgery of moderate duration
Authors: Servin F. S. , Desmonts J. M. , Melloni C. , Martinelli G.
Published: January 2004

This study, conducted in 110 patients undergoing surgery of moderate duration, compared the pharmacodynamic equivalence, efficacy and safety of 1% and 2% formulations of propofol. Anaesthesia was induced with propofol 2 mgkg−1 given over 40 s and supplementary bolus injections of propofol were given if needed. There were no significant differences between the groups in mean induction times, total induction doses of propofol, frequency and mean duration of apnoea, fentanyl requirements or mean recovery times (times to eyes opening and to orientation). Isolated statistically significant group differences in systolic and diastolic blood pressures and heart rates during induction were not considered clinically significant. Discomfort on injection occurred in 40% and 52% of those given 1% (n = 55) and 2% (n = 55) propofol, respectively; there was no statistically significant group difference in severity. No major adverse effects were reported. This study showed that the 2% formulation has a similar safety and pharmacodynamic profile to the 1% formulation.
Home‐readiness after spinal anaesthesia with small doses of hyperbaric 0.5% bupivacaine
Authors: Tarkkila P. , Huhtala J. , Tuominen M.
Published: January 2004

Fifty‐four patients were studied prospectively to evaluate home‐readiness after a small dose (1 or 2 ml) of subarachnoid hyperbaric 0.5% bupivacaine. The block regressed significantly earlier in the 1 ml group than in the 2 ml group (p < 0.05). The patients were also able to walk significantly earlier in the 1 ml group (median 161 min and 231 min in the 1 ml and 2 ml groups, respectively) (p < 0.05). However, there were no significant differences between the groups in time of ability to void. We conclude that adequate surgical anaesthesia can be achieved with small doses of hyperbaric bupivacaine used for spinal anaesthesia. Although the sensory and motor block after 1 or 2 ml hyperbaric bupivacaine recovered within a reasonable time for day‐case surgery, in some patients recovery of the ability to void was delayed to an undesirable extent.
Event‐related evoked potential responses (P300) following epidural methylprednisolone therapy in chronic low back pain patients
Authors: Tandon O. P. , Kumar A. , Dhar D. , Battacharya A.
Published: January 2004

P300 event‐related potentials were recorded in 12 patients with chronic low back pain following epidural methylprednisolone administration. The values of absolute peak latencies and amplitudes of P300 were recorded before (baseline) and on the 5th and 10th days following epidural injection. Intensity of pain was also recorded using a 10‐cm visual analogue scale score. The absolute peak latency of P300 significantly decreased on the 5th and 10th days following epidural methylprednisolone (p < 0.001) when compared with baseline value. Visual analogue scores also decreased significantly (p < 0.001) after the 5th and 10th days of epidural methylprednisolone. These observations suggest that following epidural methylprednisolone administration in chronic low back pain patients, significant improvement in cognitive functions and pain relief go hand in hand.
Learning curves for fibreoptic nasotracheal intubation when using the endoscopic video camera
Authors: Smith J. E. , Jackson A. P. F. , Hurdley J. , Clifton P. J. M.
Published: January 2004

We have followed the progress of 12 anaesthetic trainees as they learnt how to perform fibreoptic nasotracheal intubation with the aid of an endoscopic video camera system. Each trainee had a structured teaching session on a bronchial tree model, viewed an instructional videotape and then performed 20 nasotracheal intubations on anaesthetised oral surgery patients. Trainees were required to perform the endoscopies under full visual control and to demonstrate airway anatomy as they advanced the fibrescope. They were allowed up to two 2½ min periods to complete nasotracheal endoscopy. All 240 endoscopies were completed within the time limit: 228 were completed within 2½ min and 12 (5%) were completed during the second 2½ min period. We constructed a group learning curve from the pooled data. The half‐life of the curve was nine endoscopies. The best fit value for the first endoscopy time was 132 s, and after the 18th (two half‐lives) it was 49 s. We analysed the theoretical basis for deriving a learning curve from raw data. This information could form a rational basis for the design of fibreoptic training programmes using video imaging systems.
The anti‐emetic efficacy of a combination of ondansetron and droperidol
Authors: Koivuranta M. , Jokela R. , Kiviluoma K. , Alahuhta S.
Published: January 2004

The anti‐emetic efficacy of a combination of ondansetron 8 mg with either droperidol 0.75 mg or 1.25 mg given prophylactically was studied in a randomised blinded trial of 94 female inpatients with a previous history of postoperative nausea and vomiting and scheduled to have laparoscopic surgery. A standardised general anaesthetic technique was used for all patients. The mean estimated risk of postoperative sickness according to predictive patient characteristics was 65% for both treatment groups. During the 24 h study period, the proportion of patients with nausea was similar (35%) in both groups, and vomiting occurred in 16% and 14% of the patients in the droperidol 0.75 mg and 1.25 mg groups, respectively. No serious adverse events were observed. Ondansetron in combination with droperidol 0.75 mg resulted in less drowsiness than in combination with 1.25 mg (p = 0.03). In conclusion, a prophylactic combination treatment of ondansetron 8 mg with a small dose of droperidol was clinically effective and well tolerated for the prevention of postoperative nausea and vomiting after laparoscopic surgery in patients with a high probability of nausea and vomiting.
Incidence of intra‐operative bradycardiaComparison of atracurium and vecuronium in gynaecological surgery
Authors: Hameedullah H. , Khan F. A.
Published: January 2004

Intra‐operative bradycardia is one of the most common cardiac arrhythmias observed in clinical anaesthetic practice and can lead to a potentially dangerous outcome. In a randomised double‐blind trial, 50 female patients undergoing elective abdominal hysterectomy were divided into two groups. Group I received atracurium and group II received vecuronium as a neuromuscular blocking agent in a balanced anaesthetic technique. The incidence of bradycardia was compared among the two groups. Bradycardia was defined as a heart rate of less than 60 beat.min−1. A heart rate of less than 45 beat.min−1 was labelled as severe bradycardia and symptomatic bradycardia was defined as bradycardia associated with hypotension. The two groups were similar in their demographic characteristics. The results showed that there was no statistically significant difference among the two groups regarding the incidence of simple bradycardia. However, the incidence of severe bradycardia or symptomatic bradycardia requiring treatment was significantly higher in the vecuronium group.
Outcome of intensive care in the elderly
Authors: Djaiani G. , Ridley S.
Published: January 2004

The long‐term survival of elderly patients following critical illness in the United Kingdom has not previously been studied. The demographic (age, sex, diagnosis, severity of illness) and treatment details (admission type, length of treatment, prior surgery) of all critically ill patients aged over 70 years were recorded. The 1‐year survival of such patients was measured and compared with that of a matched normal population. Of 474 patients aged over 70 years, 88 patients died on the intensive care unit (19% mortality) and a further 133 died within 1 year (total mortality 47%). The 1‐year survival of patients aged <85 years was 56% which was significantly better than that of patients over 85 years (27%). The survival of all critically ill elderly patients was significantly poorer than that of a matched normal population (1‐year survival 93%). Logistic regression revealed that age, diagnosis and severity of illness are independent predictors of 1‐year survival.
A comparison of remifentanil and alfentanil in patients undergoing major abdominal surgery
Authors: Schüttler J. , Albrecht S. , Breivik H. , Osnes S. , Prys‐Roberts C. , Holder K. , Chauvin M. , Viby‐Mogensen J. , Mogensen T. , Gustafson I. , Lof L. , Noronha D. , Kirkham A. J. T.
Published: January 2004

The efficacy and safety of remifentanil and alfentanil for patients undergoing major abdominal surgery were compared. Premedicated patients received a loading dose of remifentanil (1.0 μg.kg−1; n =116) and a continuous infusion of 0.5 μg.kg−1.min−1, or a loading dose of alfentanil (25 μg.kg−1; n =118) and a continuous infusion of 1.0 μg.kg−1.min−1. Propofol was administered (10 mg every 10 s) until loss of consciousness. Patients’ lungs were ventilated with 66% nitrous oxide and 0.5% (end‐tidal) isoflurane in oxygen. The study drug infusion rate was reduced by 50% 5 min after intubation. Alfentanil was discontinued 15 min before the end of surgery, whereas remifentanil was continued in the immediate postoperative period at a reduced dose. Responses to intubation (28%) and skin incision (17%) occurred approximately twice as often in the alfentanil group (15% and 8%; p = 0.014 and p = 0.037, respectively). More patients receiving alfentanil had one or more responses to surgery (72% vs. 57%; p = 0.016). The time to spontaneous respiration, adequate respiration, response to verbal command and time to recovery room discharge were similar. However, owing to decreased variability, the time to extubation was shorter with remifentanil than with alfentanil (p =0.048). There was a similar overall incidence of adverse events in both groups, 82% and 75% of patients, respectively. Adverse events associated with remifentanil were rapidly controlled by dose reductions. The incidence of intra‐operative hypotension and bradycardia was higher in the remifentanil group (p ≤0.033). An initial remifentanil infusion rate of 0.1 μg.kg−1.min−1 titrated to individual need provided postoperative pain relief in the presence of adequate respiration in 71% of patients. When using remifentanil in the immediate postoperative setting, rapid administration of bolus doses and infusion rate increases resulted in a relatively high incidence of muscle rigidity, respiratory depression and apnoea. Changing the postoperative regimen to avoid rapid changes in remifentanil blood concentration resulted in more effective analgesia and dramatically reduced the incidence of adverse events during this period. In patients undergoing major abdominal surgery, remifentanil appears to offer superior intra‐operative haemodynamic stability during stressful surgical events compared with alfentanil without compromising recovery from anaesthesia. Remifentanil can be administered as a postoperative analgesic agent at a starting dose of 0.1 μg.kg−1.min−1; however, it should only be used in the presence of adequate supervision and monitoring of the patient. Administration of bolus doses is not recommended in this setting.
Damage to the laryngeal mask by residual fluid in the cuff
Authors: Asai T. , Koga K. , Morris S.
Published: January 2004

It has been suggested that, in some situations, the cuff of the laryngeal mask should be filled with fluid. We speculated that this practice might damage the device during sterilisation in an autoclave. We studied whether injection of a small volume of water into the cuff of the laryngeal mask and subsequent sterilisation affected the integrity of the cuff. First, a pressure–volume relationship for each of 20 new masks was obtained by inflating the cuff with increasing volumes of air (5–45 ml). The masks were then randomly allocated into four groups (W0, W0.25, W0.5 or W1.0), 0, 0.25, 0.5 or 1.0 ml of water was injected into the cuff and the mask was then sterilised in an autoclave. After sterilisation, the shape of the cuff was examined and pressure–volume relationships were obtained again. The baseline intracuff pressures were similar in the four groups. After sterilisation, the pressure was significantly lower in groups W0.25, W0.5 and W1.0 than in group W0 (p < 0.05). Two masks in group W1.0 lost their integrity, resulting in herniation of and rupture of the cuff. We conclude that the cuff of the laryngeal mask should not be inflated with fluid unless the device is discarded afterwards.
Rebreathing in the Mapleson A, C and D breathing systems with sinusoidal and exponential flow waveforms
Authors: Cook L. B.
Published: January 2004

The degree of rebreathing in Mapleson A, C and D breathing systems for sinusoidal and exponential flow waveforms is analysed mathematically. The effects of altering the I:E ratio and of introducing an expiratory pause are investigated. The results for sinusoidal waveforms closely resemble those for a square wave. Exponential flow waveforms produce results similar to triangular flow waveforms. The Mapleson A system is always the most efficient. The Mapleson C system is efficient when the I:E ratio is 1:1, becoming less efficient with longer expiration and very inefficient with an expiratory pause. The Mapleson D system becomes efficient when the expiratory pause is long.
The safety of patient‐controlled sedation
Authors: Thorpe S. J. , Balakrishnan V. R. , Cook L. B.
Published: January 2004

We have investigated the safety of a previously described method of patient‐controlled sedation in 100 healthy patients presenting for elective surgery. The device used 0.33‐ml boluses of propofol (10 mg.ml−1) infused over 6 s with no lockout. All patients attempted to put themselves to sleep by pressing a button on the hand‐held device. The oxygen saturation, heart rate, sedation score and airway patency were noted every minute. When the patient stopped pressing the button, the anaesthetist took over the handset and continued pressing the button until the patient became unresponsive. The system allowed rapid sedation. Only five patients were still anxious after 2 min. After 3 min, no patient was still anxious and more than 70 patients had slurred speech. When they stopped pressing the button, 11 patients were judged oversedated, of whom two were unresponsive. One patient's oxygen saturation decreased transiently to 84%: no other patient's oxygen saturation decreased below 90%. There were no other significant changes. We conclude that the system studied works well but carries too high a risk of oversedation for unsupervised use.
Plasma volume estimation using indocyanine green with biexponential regression analysis of the decay curves
Authors: Sekimoto M. , Fukui M. , Fujita K.
Published: January 2004

We studied seven analytical methods of estimating the plasma volume from the decay curves of indocyanine green. Fifteen volunteers received 1.0 mgkg−1 of the dye by intravenous injection and the plasma concentration was measured continuously using spectrophotometry. Plasma volumes were calculated using three single‐regression methods (1‐a, 1‐b, 1‐c) and four biexponential regression methods (2‐a, 2‐b, 2‐c, 2‐d). The means (SD) of 1‐a, 1‐b and 1‐c were 39 (5.0), 44 (5.7) and 54 (11.5) mlkg−1, respectively, and these were significantly different from each other (p < 0.05). The values for methods 2‐b, 2‐c and 2‐d were similar to each other: 39 (4.6), 40 (4.1) and 40 (4.0) mlkg−1, respectively. These required more than 3 min circulation or mixing time. When the time allowed for mixing was less than 3 min (method 2‐a) the plasma volume was underestimated. We conclude that plasma volume estimation using indocyanine green and spectrophotometry is most accurate when the mixing time is adequate (3–5 min) and the decay curves are analysed using biexponential regression.
The effect of position on autonomic nervous activity in late pregnancy
Authors: Kuo C.‐D. , Chen G.‐Y. , Yang M.‐J. , Tsai Y.‐S.
Published: January 2004

We investigated the effect of three different recumbent positions on autonomic nervous activity in late pregnancy. Thirty pregnant and 24 nonpregnant aged‐matched women were studied, and measures of heart rate variability in both time and frequency domains were compared using supine, right and left lateral decubitus positions. In the nonpregnant women, the normalised high‐frequency power was greatest in the right lateral decubitus position. In the pregnant women, the normalised high‐frequency power was lowest and the low/high‐frequency power ratio was greatest in the supine position. Both the percentage decrease of normalised high‐frequency power and the percentage increase of low/high‐frequency power ratio in the supine and right lateral positions were greater than those in the left lateral position. For women in late pregnancy, the left lateral decubitus position may be beneficial because cardiac vagal activity is least suppressed and cardiac sympathetic activity is least enhanced. Aortocaval compression might be the mechanism underlying the change in cardiac autonomic nervous activity when supine and right lateral decubitus positions are assumed in late pregnancy.
Sciatic nerve palsy following uneventful sciatic nerve block
Authors: Bonner S. M. , Pridie A. K.
Published: January 2004

We describe the loss of function in the sciatic nerve after an uneventful sciatic nerve block using 25 ml of lignocaine 1% with adrenaline 1 in 200 000 in a patient receiving β blocker drugs. Lack of pain on injection and complete regeneration of the nerve after 12 months in a patient with severe peripheral vascular disease led us to postulate ischaemic nerve damage as a mechanism of injury. Adrenaline‐induced unopposed α‐mediated vasoconstriction in a β‐blocked patient is suggested as a possible mechanism of peripheral nerve injury worthy of further investigation.