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Showing papers in "BJA: British Journal of Anaesthesia in 1996"


Journal ArticleDOI
TL;DR: It is concluded that ASA physical status classification was a predictor of postoperative outcome using both univariate analysis and calculation of the odds ratio of the risk of developing a postoperative complication by means of a logistic regression model.
Abstract: In a prospective study of 6301 surgical patients in a university hospital, we examined the strength of association between ASA physical status classification and perioperative risk factors, and postoperative outcome, using both univariate analysis and calculation of the odds ratio of the risk of developing a postoperative complication by means of a logistic regression model. Univariate analysis showed a significant correlation (P

884 citations


Journal ArticleDOI
TL;DR: A complex interaction of cytokines and cytokine-neutralizing molecules probably determines the clinical presentation and course of sepsis, and intervention in this sequence of events to modify the host inflammatory responses may prove to be a beneficial treatment strategy.
Abstract: Sepsis is a constellation of clinical signs and symptoms resulting from excessive systemic host inflammatory response to infection. This inflammatory response is largely mediated by cytokines, which are released into the systemic circulation. Plasma concentrations of specific cytokines, TNF alpha, IL-1 beta, IL-6 and IL-8 are frequently elevated in human sepsis and cytokine concentrations correlate with severity and outcome of sepsis. In addition to pro-inflammatory cytokines, soluble cytokine receptors, cytokine receptor antagonists and counter-inflammatory cytokines are also produced in large quantities in patients with sepsis; however, the specific role of these molecules in sepsis remains undefined. A complex interaction of cytokines and cytokine-neutralizing molecules probably determines the clinical presentation and course of sepsis. Intervening in this sequence of events to modify the host inflammatory responses may prove to be a beneficial treatment strategy for sepsis, but currently tested anticytokine therapies have been largely unsuccessful.

473 citations



Journal ArticleDOI
TL;DR: Clinically important risk of major harm reduces the usefulness of omitting N2O to prevent postoperative emesis, and the combined NNT to prevent both early and late vomiting with a N1O-free anaesthetic is about 13.
Abstract: We have reviewed randomized controlled trials to assess the effectiveness and safety of anaesthetics which omitted nitrous oxide (N2O) to prevent postoperative nausea and vomiting (PONV). Early and late PONV (6 and 48 h after operation, respectively), and adverse effects were evaluated using the numbers-needed-to-treat (NNT) method. In 24 reports with information on 2478 patients, the mean incidence of early and late vomiting with N2O (control) was 17% and 30%, respectively. Omitting N2O significantly reduced vomiting compared with a N2O regimen; the combined NNT to prevent both early and late vomiting with a N2O-free regimen was about 13 (95% confidence intervals (CI) 9, 30). The magnitude of the effect depended on the incidence of vomiting in controls. In studies with a baseline risk higher than the mean of all reports, the NNT to prevent both early and late vomiting with a N2O-free anaesthetic was 5 (95% CI 4, 10). When the baseline risk was lower than the mean, omitting N2O did not improve outcome. Omitting N2O had no effect on complete control of emesis or nausea. The NNT for intraoperative awareness with a N2O-free anaesthetic was 46 compared with anaesthetics where N2O was used. This clinically important risk of major harm reduces the usefulness of omitting N2O to prevent postoperative emesis.

316 citations


Journal ArticleDOI
TL;DR: Regression analysis showed that data for humans derived from a comprehensive literature survey were consistent, for age > 1 yr, with log10 MAC decreasing with increasing age at the same rate for all inhaled anaesthetics; approximately equivalent to 6% change per decade of age.
Abstract: It is well known that MAC, the minimum alveolar concentration required to prevent movement in response to surgical incision in 50% of patients, decreases with age. Regression analysis showed that data for humans derived from a comprehensive literature survey were consistent, for age > 1 yr, with log10 MAC decreasing with increasing age at the same rate for all inhaled anaesthetics; approximately equivalent to 6% change per decade of age. With some slight reservation on differences between data from different institutions, the present data for humans are consistent (for age > 1 yr), with the equation MAC = a x 10bx where x = difference in age (in years) from 40, b = -0.00269 (95% confidence limits (CL) -0.0030, -0.0024) and a = MAC at age 40 yr, which, for anaesthetics currently in use clinically, is given by: halothane, 0.75%; isoflurane, 1.17%; enflurane, 1.63%; sevoflurane, 1.80%; desflurane 6.6%; nitrous oxide, 104%; with 95% CL of approximately +/- 7% (+/- 10% for desflurane, +/- 17% for enflurane).

315 citations


Journal ArticleDOI
TL;DR: The use of general anaesthesia had decreased from 83% in 1981 to 23% in 1994 but despite this, the incidence of failed intubation has increased and exposure of trainees to obstetric general anaesthetics has decreased by one-third.
Abstract: We have reviewed 5802 Caesarean sections performed during general anaesthesia Our use of general anaesthesia had decreased from 83% in 1981 to 23% in 1994 Despite this, the incidence of failed intubation has increased from 1 in 1984 to 1 in 250 in 1994 The problems associated with general anaesthesia in the obstetric population are increasing Asians and African/Afrocaribbeans were represented disproportionately because of the increased use of general anaesthesia in these patients Exposure of trainees to obstetric general anaesthetics has decreased by one-third

296 citations


Journal ArticleDOI
TL;DR: Clinical studies using gastrointestinal tonometry have produced evidence to support the concept of a link between inadequate splanchnic tissue perfusion and multiple organ failure.
Abstract: The splanchnic region participates in the regulation of circulating blood volume and systemic blood pressure [60]. Major reduction of splanchnic blood volume and flow can be vital in defending the perfusion of the brain and the heart in acute hypovolaemia, but prolonged hypoperfusion of the splanchnic region will inevitably lead to hypoxic tissue injury [55]. The splanchnic region is also an important source and target of inflammatory mediators, which have a major impact on both systemic and regional blood flow and tissue functions [45]. The splanchnic circulation is in close interaction with the systemic haemodynamics under normal conditions. In the intensive care patient at risk of multiple organ failure, there is a complex and poorly understood interaction between the splanchnic blood flow, metabolic demands of the tissues and the mediators of inflammation and vasoregulation. Inadequate splanchnic blood flow and tissue perfusion are likely to contribute to the development of organ failures and increased mortality in various categories of intensive care patients [8]. Monitoring of gastric intramucosal pH (pHi) or intramucosal PCO2 by gastrointestinal tonometry has provided an indicator of splanchnic tissue perfusion that is feasible for clinical use in intensive care [15, 18, 19, 27, 30, 32, 47, 48, 49]. Clinical studies using gastrointestinal tonometry have produced evidence to support the concept of a link between inadequate splanchnic tissue perfusion and multiple organ failure. Gastric intramucosal acidosis, suggesting inadequate splanchnic tissue perfusion, is relatively common: up to 50 % of patients admitted to intensive care with signs of circulatory failure, 50 % of patients undergoing elective cardiac surgery and 18 % of patients undergoing abdominal aortic surgery have at least transient episodes of gastric intramucosal acidosis [15, 18, 19, 30, 32, 47, 48, 49]. Patients with gastric intramucosal acidosis on admission to intensive care have an increased occurrence of multiple organ failure and increased mortality [30, 32, 47, 48]. Prevention and treatment of gastric intramucosal acidosis by administration of fluids and vasoactive drugs improves the outcome of

222 citations


Journal ArticleDOI
TL;DR: The aim of this article is to review the incidence and duration of postoperative sleep disturbances, and to evaluate possible mechanisms and potential implications for postoperative outcome.
Abstract: Major surgery is beset by complications such as pulmonary, cardiac, thromboembolic and cerebral dysfunction, which cannot be attributed solely to inadequate surgical and anaesthetic techniques, but rather to increased organ demands caused by the endocrine metabolic response to surgical trauma [33]. Postoperative cerebral dysfunction comprises delirium, confusion and milder degrees of mental dysfunction [1, 48, 53, 62], and disturbances in the normal sleep pattern [4, 7, 9, 13, 17, 34, 39, 42, 65]. Changes in early postoperative sleep [4, 7, 8, 13, 17, 34, 39, 42, 65] and sleep after non-surgical stress [10, 20, 24, 26, 27, 29, 60] are characterized by a decrease in total sleep time, elimination of rapid eye movement (REM) sleep, a marked reduction in the amount of slow wave sleep (SWS) and increased amounts of non-REM (N-REM) sleep stage 2. Recent data have suggested that postoperative sleep disturbances may be involved in the development of altered mental function [27], postoperative episodic hypoxaemia [38, 65] and haemodynamic instability [40]. The aim of this article, therefore, is to review the incidence and duration of postoperative sleep disturbances, and to evaluate possible mechanisms and potential implications for postoperative outcome.

220 citations


Journal ArticleDOI
TL;DR: Male patients, aged 27-74 yr, without hypertension or overt cardiovascular disease were premedicated with temazepam 20 mg orally and allocated randomly to receive sedation with either midazolam in a dose sufficient to provide light sedation (retained response to loud voice) or ketamine 1 mg kg-1 (11 patients).
Abstract: Male patients, aged 27-74 yr, without hypertension or overt cardiovascular disease were premedicated with temazepam 20 mg orally and allocated randomly to receive sedation with either midazolam (12 patients) in a dose sufficient to provide light sedation (retained response to loud voice) or ketamine 1 mg kg-1 (11 patients). Median midazolam dose was 0.08 (interquartile range 0.02) mg kg-1. The activity of the muscles of the tongue, anterior neck and scalene group was measured with surface electrodes and compared with the awake state. Muscle activity decreased significantly after midazolam in each group of muscles, to median values of 42%, 28% and 33%, respectively, of awake values. Airway obstruction occurred in 10 of 12 patients and during obstruction muscle activity increased significantly to 69%, 73% and 52% of awake values, but in all cases this was insufficient to overcome the obstruction. After ketamine, activity did not change significantly and there were no episodes of airway obstruction. Phasic muscle activity was noted after sedation in 11 subjects but there was no difference in the incidence between the two groups (midazolam, six patients; ketamine, five patients).

219 citations


Journal ArticleDOI
Dawn Carroll1, M. R. Tramèr1, Henry J McQuay1, B. A. Nye1, Andrew Moore1 
TL;DR: The evidence for the importance of randomization of transcutaneous electrical nerve stimulation (TENS) in acute postoperative pain was examined; controlled studies were sought; randomization and analgesic and adverse effect outcomes were summarized.
Abstract: We set out to examine the evidence for the importance of randomization of transcutaneous electrical nerve stimulation (TENS) in acute postoperative pain. Controlled studies were sought; randomization and analgesic and adverse effect outcomes were summarized. Forty-six reports were identified by searching strategies. Seventeen reports with 786 patients could be regarded unequivocally as randomized controlled trials (RCT) in acute postoperative pain. No meta-analysis was possible. In 15 of 17 RCT, we judged there to be no benefit of TENS compared with placebo. Of the 29 excluded trials, 19 had pain outcomes but were not RCT; in 17 of these 19 TENS studies, the authors concluded that TENS had a positive analgesic effect. No adverse effects were reported. Non-randomized studies overestimated treatment effects.

216 citations


Journal ArticleDOI
TL;DR: It is concluded that haemodilution per se increases the coagulability of whole blood in vitro, but that saline haemmodilution has a more marked effect on final clot strength.
Abstract: It has been suggested that haemodilution with saline may increase whole blood coagulation. This study was conducted in two parts. First, we investigated the effect of in vitro dilution of blood with saline on whole blood coagulation as measured by the thrombelastogram (TEG). Blood (4 ml) was diluted with 0.9% saline 1 ml and coagulation compared with that of an undiluted control specimen obtained concurrently from the same subject. In the second part, the study was repeated using a modified gelatin colloidal solution (Haemaccel) as the diluent. The r time, k time and r + k time were decreased relative to control in both diluent groups. The alpha angles were increased compared with control in both groups while maximum amplitude was unchanged in the Haemaccel diluted group. We conclude that haemodilution per se increases the coagulability of whole blood in vitro, but that saline haemodilution has a more marked effect on final clot strength.

Journal ArticleDOI
TL;DR: The large volume of ketamine required was partly swallowed and led to an unacceptable variability of effect that precludes this route for induction of anaesthesia, but using high doses via the nasal route produced high plasma concentrations of ketamines similar to those that induce anaesthesia.
Abstract: It has been suggested that nasal administration of ketamine may be used to induce anaesthesia in paediatric patients. We have examined the pharmacokinetics of ketamine and norketamine after nasal administration compared with rectal and i.v. administration in young children. During halothane anaesthesia, 32 children, aged 2-9 yr, weight 10-30 kg, were allocated randomly to receive ketamine 3 mg kg-1 nasally (group IN3) or ketamine 9 mg kg-1 nasally (group IN9); ketamine 9 mg kg-1 rectally (group IR9); or ketamine 3 mg kg-1 i.v. (group IV3). Venous blood samples were obtained before and up to 360 min after administration of ketamine. Plasma concentrations of ketamine and norketamine were measured by gas liquid chromatography. Statistical comparisons were performed using ANOVA and the Kruskall-Wallis test, with P

Journal ArticleDOI
TL;DR: A model to describe the rate of oxyhaemoglobin desaturation during apnoea takes into account the non-steady-state kinetics which pertain to this situation, and describes a manoeuvre to accommodate the effect of the Bohr shift which is related to the increase in FACO2 during apNoea.
Abstract: We have developed a model to describe the rate of oxyhaemoglobin desaturation during apnoea. This model takes into account the non-steady-state kinetics which pertain to this situation. We first derived a mathematical expression for instantaneous oxygen flux rate from the alveolar compartment. We then derived an expression to describe the effect of shunt on this flux. The effect of circulation time on real-time arterial mixed venous oxygen content difference and oxygen flux in the lung was determined graphically. We finally described a manoeuvre to accommodate the effect of the Bohr shift which is related to the increase in FACO2 during apnoea. We present plots of arterial oxyhaemoglobin saturation (SaO2) vs duration of apnoea to illustrate the individual effects of the initial fractional concentration of oxygen in the alveolus (FAO2initial), alveolar volume (VA), shunt fraction (QS/QT), oxygen consumption rate (VO2), total blood volume (QT) and haemoglobin concentration (Hb). The model is illustrated by examples of paediatric, morbidly obese and post-operative scenarios. The postoperative scenario is particularly notable for the effect of a combination of small changes in individual variables leading to a large overall effect on the rate of oxyhaemoglobin desaturation.

Journal ArticleDOI
Dafydd G. Thomas1, S. C. Robson1, N. Redfern1, D. Hughes1, Richard J. Boys1 
TL;DR: The results of the present study support the use of phenylephrine for maintenance of maternal arterial pressure during spinal anaesthesia for elective Caesarean section.
Abstract: Thirty-eight healthy women undergoing elective Caesarean section under spinal anaesthesia at term were allocated randomly to receive boluses of either phenylephrine 100 micrograms or ephedrine 5 mg for maintenance of maternal arterial pressure. The indication for administration of vasopressor was a reduction in systolic pressure to < or = 90% of baseline values. Maternal arterial pressure (BP) and heart rate (HR) were measured every minute by automated oscillometry. Cardiac output (CO) was measured by cross-sectional and Doppler echocardiography before and after preloading with 1500 ml Ringer lactate solution and then every 2 min after administration of bupivacaine. Umbilical artery pulsatility index (PI) was measured using Doppler before and after spinal anaesthesia. The median (range) number of boluses of phenylephrine and ephedrine was similar; 6 (1-10) vs 4 (1-8) respectively. Maternal systolic BP and CO changes were similar in both groups, but the mean [95% CI] maximum percentage change in maternal HR was larger in the phenylephrine group (-28.5 [-24.2, -32.9]%) than in the ephedrine group (-14.4 [-10.6, -18.2]%). As a consequence atropine was required in 11/19 women in the phenylephrine group compared with 2/19 in the ephedrine group (P < 0.01). Mean umbilical artery pH [95% CI] was higher in the phenylephrine group (7.29 [7.28-7.30]) than in the ephedrine group (7.27 [7.25-7.28]). The results of the present study support the use of phenylephrine for maintenance of maternal arterial pressure during spinal anaesthesia for elective Caesarean section.

Journal ArticleDOI
TL;DR: The time profile-concentration changes of increased MAP and renin-aldosterone suggests a cause-effect relationship and increased intra-abdominal pressure and reverse Trendelenburg positioning may reduce cardiac output and renal blood flow.
Abstract: We have assessed the potential for myocardial ischaemia during laparoscopic cholecystectomy in 16 otherwise healthy patients. Continuous ambulatory ECG monitoring was commenced 12 h before operation and continued for 24 h after operation. The neuroendocrine stress response was assessed by measuring plasma concentrations of adrenaline and noradrenaline, human growth hormone, cortisol, renin and aldosterone, and prolactin, at specified times during surgery. Acute ST segment changes in the ECG occurred in only two patients. These episodes were independent of creation of pneumoperitoneum and changes in position. Acute intraoperative increases in MAP were noted during insufflation of carbon dioxide and reverse Trendelenburg positioning (P 0.05). There was a linear correlation between changes in plasma renin and aldosterone concentrations and MAP (r = 0.97 and r = 0.85, respectively). Prolactin concentrations increased four-fold after induction of anaesthesia. Cortisol, HGH, adrenaline and noradrenaline concentrations increased after deflation of the pneumoperitoneum. The time profile-concentration changes of increased MAP and renin-aldosterone suggests a cause-effect relationship. Increased intra-abdominal pressure and reverse Trendelenburg positioning may reduce cardiac output and renal blood flow. The early increase in prolactin concentration was probably secondary to the effect of the opioid fentanyl.


Journal ArticleDOI
TL;DR: The incidence of nausea and emetic episodes in the ondansetron with dexamethasone group was lower than in the placebo group, and the total number of patients treated for postoperative nausea and vomiting was unchanged.
Abstract: We studied 100 ASA I-II females undergoing general anaesthesia for major gynaecological surgery, in a prospective, double-blind, placebo-controlled, randomized study. Patients received one of four regimens for the prevention of postoperative nausea and vomiting (PONV): ondansetron 4 mg (n = 25), dexamethasone 8 mg (n = 25), ondansetron with dexamethasone (4 mg and 8 mg, respectively, n = 25) or placebo (saline, n = 25) There were no differences in background factors or factors related to operation and anaesthesia, morphine consumption, pain or side effects between groups. The incidence of nausea and emetic episodes in the ondansetron with dexamethasone group was lower than in the placebo (P < 0.01), ondansetron (P < 0.05) and dexamethasone (P = 0.057) groups. There were no differences between ondansetron and dexamethasone, and both were more effective than placebo (P < 0.05 and P < 0.01, respectively). Dexamethasone appeared to be preferable in preventing nausea than emetic episodes. Fewer patients in the ondansetron with dexamethasone group needed antimetic rescue (P < 0.01 vs placebo and P < 0.05 vs ondansetron). We conclude that prophylactic administration of combined ondansetron and dexamethasone is effective in preventing PONV.

Journal ArticleDOI
TL;DR: Ketamine (racemic) prolonged the reaction time more than ketamine (S+) and both drugs affected pain caused by repeated stimuli or stimuli of long duration equally or more than a single stimulus of short duration.
Abstract: We have compared the analgesic efficacy of the racemic mixture and the stereoisomer (S+) of the NMDA antagonist ketamine. In a double-blind, three-way crossover, placebo-controlled study, we assessed the following: pain evoked by small/large area pressure stimuli, pain detection threshold and pain ratings to small/large area of heat stimuli, pain detection threshold and pain rating to heat stimuli of brief/long duration, summation pain threshold and pain ratings to repeated heat/electrical stimuli, side effects and reaction time. Plasma concentrations of 350 ng ml-1 for ketamine (racemic) and 180 ng ml-1 for ketamine (S+) were tried. We found that ketamine (racemic) prolonged the reaction time more than ketamine (S+). Both drugs affected pain caused by repeated stimuli or stimuli of long duration equally or more than a single stimulus of short duration. They also affected pain evoked from large areas equally or more than pain evoked from small areas. The (S+)-isomer was approximately twice as potent as the racemic mixture of ketamine in inhibiting central summation.

Journal ArticleDOI
TL;DR: The analgesic effects of ketamine in the burn injury model are in agreement with results from experimental studies, and can be distinguished from those of local anaesthetics and opioids.
Abstract: Ketamine reduces nociception by binding noncompetitively to the N-methyl-D-aspartate (NMDA) receptor, activation of which increases spinal hypersensitivity We studied 19 healthy, unmedicated male volunteers, aged 20-31 yr Burn injuries were produced on the medial surface of the dominant calf with a 25 x 50 mm rectangular thermode On 3 separate days, at least 1 week apart, subjects received a bolus of either ketamine 015 mg kg-1, ketamine 030 mg kg-1 or placebo, delivered by a mechanical infusion pump over 15 min The bolus was followed by continuous infusion of ketamine 015 mg kg-1 h-1, ketamine 030 mg kg-1 h-1 or placebo, respectively, for 135 min Ketamine reduced the magnitude of both primary and secondary hyperalgesia, and also pain evoked by prolonged noxious heat stimulation, in a dose-dependent manner In contrast, ketamine did not alter phasic heat pain perception (perception of transient, painful, thermal stimuli) in undamaged skin The analgesic effects of ketamine in the burn injury model are in agreement with results from experimental studies, and can be distinguished from those of local anaesthetics and opioids Side effects caused by continuous infusion of ketamine 015 and 030 mg kg-1 h-1 were frequent but clinically acceptable

Journal ArticleDOI
TL;DR: Although the number of patients with severe thrombocytopenia was small, a platelet count of 75 x 10(9) litre-1 should be associated with adequate haemostasis, and there was no correlation between bleeding time and any measured TEG variable.
Abstract: We have measured platelet count, bleeding time and thrombelastography (TEG) variables and the correlation between these variables in 49 pregnant patients presenting with pre-eclampsia or eclampsia. Eighteen patients (37%) had a platelet count 9.5 min in 13 (27%) patients and the TEG was abnormal in four (8%). The TEG variables, k time and maximum amplitude (MA) had a strong correlation with platelet count (k time-platelet count 100 x 10(9) litre-1) but prolonged bleeding time, the TEG was normal, suggesting adequate haemostasis. An MA of 53 mm, which is the lower limit for normal pregnancy, correlated with a platelet count of 54 x 10(9) litre-1 (95% confidence limits 40-75 x 10(9) litre-1). Although the number of patients with severe thrombocytopenia was small, a platelet count of 75 x 10(9) litre-1 should be associated with adequate haemostasis.

Journal ArticleDOI
TL;DR: Sevoflurane has been in clinical use in Japan since 1990 and has recently gained approval for use in Great Britain, the United States and much of the rest of the world.
Abstract: In evaluating any newly introduced anaesthetic, it is worth comparing its properties with those of a theoretical “ideal” volatile agent which would have a low solubility in blood to allow for rapid equilibration between delivered concentration and the effect site in the central nervous system (CNS). This would facilitate rapid induction of anaesthesia, allow easier titration of anaesthetic dose to the desired effect during the maintenance period and permit rapid emergence and recovery at the end of anaesthesia. An ideal anaesthetic should also be easy to deliver and devoid of perioperative side effects and toxicity. Desflurane (Suprane) was the last new volatile anaesthetic introduced into clinical practice in 1992. Although relatively insoluble and easy to titrate during the maintenance period, desflurane is not a practical induction agent because of its irritant effects on the airway. The theoretically improved control over depth of anaesthesia during the maintenance period afforded by desflurane is complicated by its tendency to induce cardiovascular stimulation when the delivered concentration is increased rapidly [16, 85). In addition, desflurane requires unusually complex vaporizer technology for its administration. Sevoflurane has been in clinical use in Japan since 1990 and has recently gained approval for use in Great Britain, the United States and much of the rest of the world. This review considers the clinical properties of sevoflurane in relation to existing volatile anaesthetics (table 1) and the “ideal” volatile agent.

Journal ArticleDOI
TL;DR: Before and during movements observed in the intraoperative period or during emergence from general anaesthesia, SEF increased from 12 to 18 Hz, the power in beta band increased and theta power decreased compared with the state of adequate anaesthesia.
Abstract: To determine threshold values, sensitivity and specificity of the spectral edge frequency (SEF) of the electroencephalogram (EEG) that indicate intraoperative movements, we studied 49 patients undergoing, elective laparotomy. Extradural analgesia was used in all patients. To maintain general anaesthesia, patients in group 1 (n = 23) received 0.4-1.2 vol% isoflurane and patients in group 2 (n = 24) propofol 3-5 mg kg-1 h-1 i.v. During operation and emergence from anaesthesia, spontaneous purposeful movements were documented. The EEG was recorded continuously in the awake state until the end of anaesthesia. Power spectral analysis calculated the SEF and power in the delta, theta, alpha and beta bands and the delta ratio. Adequate anaesthesia caused a statistically significant decrease in SEF from 16 to 12 Hz. Power in the beta band decreased and power in the theta band and total power increased compared with the awake state. Before and during movements observed in the intraoperative period or during emergence from general anaesthesia, SEF increased from 12 to 18 Hz, the power in beta band increased and theta power decreased compared with the state of adequate anaesthesia. A threshold value of SEF 14 Hz to predict movements during anaesthesia had a sensitivity of 72% and specificity of 82%.

Journal ArticleDOI
TL;DR: Advances in respiratory care, and particularly in mechanical ventilation, allowed more patients to survive ARDS, and the number of patients dying with ARDS remains high; this is because the actual cause of death has shifted to MOF.
Abstract: failure was blamed for over 50 % of later fatalities [127]. Basic scientific investigations supported the addition of crystalloid solutions to blood transfusions. More vigorous fluid resuscitation during the Vietnam War led to a 20- to 30-fold reduction in the incidence of renal failure compared with the Korean experience. However, a new problem came to the forefront in Vietnam: “shock lung”—the acute respiratory distress syndrome (ARDS) [8]. Of note, in accounts of the Korean conflict, there was virtually no mention of pulmonary problems. Advances in respiratory care, and particularly in mechanical ventilation, allowed more patients to survive ARDS. Today, while our ability to sustain patients on mechanical ventilation has improved, the number of patients dying with ARDS remains high; this is because the actual cause of death has shifted to MOF. The identification of MOF as a distinct entity dates back to 1973, when Tilney, Bailey and Morgan [128] described the progressive failure of organ systems in patients following repair of ruptured abdominal aortic aneurysms. Baue [15] first suggested there was a sequential pattern to the MOF syndrome. In 1977, Eiseman, Beart and Norton [40] at our institution described its clinical presentation and coined the term “multiple organ failure”. Since that time, intensive research efforts have targeted the syndrome.

Journal ArticleDOI
TL;DR: Postoperative pulmonary function was impaired less after laparoscopic than after open cholecystectomy, and was associated with a significantly lower incidence and less severe atelectasis, better oxygenation and reduced postoperative pain and analgesia use.
Abstract: In this prospective, randomized study, we compared 42 patients undergoing laparoscopic cholecystectomy and 40 undergoing open cholecystectomy to determine if laparoscopic cholecystectomy results in less respiratory impairment and fewer respiratory complications. Pulmonary function tests, arterial blood-gas analysis and chest radiographs were obtained in both groups before operation and on the second day after operation. Postoperative pain scores and analgesic requirements were also recorded. After operation, a significant reduction in total lung capacity, functional residual capacity (FRC), forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and mid-expiratory flow (FEF25-75%) occurred after both laparoscopic and open cholecystectomy. The reductions in FRC, FEV1, FVC and FEF25-75% were smaller after laparoscopic (7%, 22%, 19% and 23%, respectively) than after open (21%, 38%, 32% and 34%, respectively) cholecystectomy. Laparoscopic cholecystectomy was also associated with a significantly lower incidence (28.6% vs 62.5%) and less severe atelectasis, better oxygenation and reduced postoperative pain and analgesia use compared with open cholecystectomy. We conclude that postoperative pulmonary function was impaired less after laparoscopic than after open cholecystectomy.

Journal ArticleDOI
TL;DR: The pronounced synergy and interaction of the components of the immune system dictate that modulation may result in either immunostimulation or immunosuppression, which is essential for the resolution of infection but may occur in an uncontrolled manner causing damage to the host.
Abstract: Severe sepsis complicated by multi-organ dysfunc- tion syndrome (MODS) is a major cause of death in intensive care units, with a mortality rate in excess of 50 %. The outcome is determined not only by the infection but also by the intensity of the immuno- inflammatory response. This response is essential for the resolution of infection but may occur in an uncontrolled manner causing damage to the host. The pronounced synergy and interaction of the components of the immune system dictate that modulation may result in either immunostimulation or immunosuppression. Coordination of the host immune response to infection and inflammation in terms of expression of the effector molecules is vital to an optimum response (Fig. 1).

Journal ArticleDOI
TL;DR: The results suggest that while sternomental distance on its own may not be an adequate sole predictor of subsequent difficult laryngoscopy the measurement should be incorporated into a series of quick and simple preoperative tests.
Abstract: Sternomental distance and view at laryngoscopy were documented in 523 parturients undergoing elective or emergency Caesarean section under general anaesthesia. Eighteen (3.5%) had a grade III or IV laryngoscopic view (Cormack and Lehane's classification) and were classified as potentially difficult tracheal intubations. There was a significant difference between sternomental distance in those patients with a grade III or IV laryngoscopic view compared with those with a grade I or II (13.17 (SD 1.54) cm vs 14.3 (1.49) cm; P = 0.0013). A sternomental distance of 13.5 cm or less with the head fully extended on the neck and the mouth closed provided, using discriminant analysis, the best cut-off point for predicting subsequent difficult laryngoscopy. A sternomental distance of 13.5 cm or less had a sensitivity, specificity, positive and negative predictive values of 66.7%, 71.1%, 7.6% and 98.4%, respectively. While there was no association between sternomental distance and age, weight, height or body mass index (BMI), there was a significant association between grade of laryngoscopy (III and IV) and older (P = 0.049) and heavier (P = 0.0495) mothers. The results suggest that while sternomental distance on its own may not be an adequate sole predictor of subsequent difficult laryngoscopy the measurement should be incorporated into a series of quick and simple preoperative tests.

Journal ArticleDOI
TL;DR: Cell injury and adaptation; mechanisms of cell death; the roles of cell injury and death in the pathophysiology of organ dysfunction; and implications for prevention and therapy of multiple organ dysfunction syndrome (MODS) are reviewed.
Abstract: Control of the rate of cell death relative to the rate of cell division maintains organ integrity and physiological homeostasis. Cell death is valuable for the organism because it removes terminally injured or unwanted cells that utilize valuable substrates and nutrients. Likewise, cell death also has value for the species, as it provides a mechanism for eliminating terminally injured individuals who consume necessary societal resources or harbour toxic pathogens. Recent advances in cellular biology have contributed substantially to our understanding of the processes of cell injury and death, and have provided the molecular tools necessary to control it. This paper reviews cell injury and adaptation; mechanisms of cell death; the roles of cell injury and death in the pathophysiology of organ dysfunction; and implications for prevention and therapy of multiple organ dysfunction syndrome (MODS).

Journal ArticleDOI
TL;DR: It is concluded that sevoflurane was superior to halothane for paediatric bronchoscopy and gastroscopy, or both, and Physiological and psychomotor recovery were more rapid after sev ofluranes than after halothanes.
Abstract: We have studied 120 infants and children, in three age groups (3-11 months, 1-5 yr and 6-15 yr), to compare anaesthesia with sevoflurane or halothane for bronchoscopy or gastroscopy, or both. Premedication or i.v. anaesthetic agents were not used. Patients were allocated randomly to receive either 7% sevoflurane or 3% halothane in 66% nitrous oxide in oxygen for induction of anaesthesia. The same inspired mixture was continued during bronchoscopy while the concentration of the inhalation agent was reduced by 50% during gastroscopy. Induction times were shorter for infants than for children and shorter for sevoflurane than for halothane. Cardiac arrhythmias were significantly more frequent during halothane than during sevoflurane anaesthesia. Physiological and psychomotor recovery were more rapid after sevoflurane than after halothane. At 24-h follow-up, children who received sevoflurane had significantly less nausea and vomiting. We conclude that sevoflurane was superior to halothane for paediatric bronchoscopy and gastroscopy.

Journal ArticleDOI
TL;DR: It is concluded that ropivacaine and bupvacaine in a concentration of 0.25% produced comparable analgesia for pain relief of labour with no detectable adverse effect on the neonate.
Abstract: Ropivacaine is a new aminoamide local anaesthetic. Compared with bupivacaine, ropivacaine possesses a higher threshold for systemic toxicity and a high selectivity for sensory fibres. We have compared prospectively these two agents in a concentration of 0.25% for extradural analgesia in labour. A total of 104 parturients requesting extradural analgesia were randomized to receive either ropivacaine or bupivacaine. The women in the bupivacaine group required more top-up doses to maintain analgesia (median 3.0 vs 2.0) (P < 0.05). The onset of sensory block, quality of analgesia, ultimate level of maximum sensory block and maternal satisfaction were similar in both groups. The incidence, intensity and duration of motor block were slightly but not significantly less in the ropivacaine group. The ropivacaine group had a higher incidence of spontaneous vaginal delivery (70.59% vs 52.00%). There was no significant difference in neonatal outcome as assessed by Apgar scores, umbilical acid-base status and neurological and adaptive capacity score at 2 and 24 h after delivery. We conclude that ropivacaine and bupivacaine in a concentration of 0.25% produced comparable analgesia for pain relief of labour with no detectable adverse effect on the neonate.

Journal ArticleDOI
TL;DR: Pre-eclampsia is a progressive disease with a very variable mode of presentation and rate of progression; of all the features of the syndrome, hypertension, pregnancy-induced proteinuria, excessive weight gain and oedema are the classic clinical manifestations.
Abstract: Fits occurring in pregnant women were recognized and recorded as early as the 4th century BC by Hippocrates [94]. The condition was termed eclampsia—a Greek word which translates literally as ‘shine forth’—implying a sudden development. Little was known about eclampsia until 1843, when Lever of Guy’s Hospital found that many of the women who had fits also had albumin in their urine [74]. However, it was not until the widespread use of the sphygmomanometer that the condition was known to be associated with raised systemic arterial pressure. Because it was recognized that albuminuria and hypertension could precede the onset of fits, the term pre-eclampsia was coined although this nomenclature is now criticized because only a small proportion of patients with pre-eclampsia subsequently develop eclampsia. Pre-eclampsia is a multisystem disorder of unknown aetiology and unique to pregnant women after 20 weeks’ gestation. In the UK, 18.6 % of maternal deaths are caused by hypertensive diseases [42]. Hypertensive disorders of pregnancy are common, affecting 10.6 % of pregnant women [109]. Preeclampsia (i.e. proteinuric hypertension) affects 5.8 % of primigravidas, and 0.4 % of secundagravid women [84]. While premature labour is the leading cause of very low birthweight neonates, the next most common cause is hypertension which accounts for 23 % of all viable very low birthweight singleton infants [2]. Pre-eclampsia is a progressive disease with a very variable mode of presentation and rate of progression. Of all the features of the syndrome, hypertension, pregnancy-induced proteinuria, excessive weight gain and oedema are the classic clinical manifestations. Other features include, thrombocytopenia, hyperuricaemia, abnormal liver function tests, haemoconcentration, hypoalbuminaemia and eclampsia. Eclampsia is a rare but serious complication of pre-eclampsia; it complicates about 1:2000 deliveries in Europe and the developed countries [45] and from 1 : 100 to 1 : 1700 deliveries in developing