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Showing papers in "BJA: British Journal of Anaesthesia in 2007"


Journal ArticleDOI
TL;DR: Understanding the multidimensional cascade of secondary brain injury offers differentiated therapeutic options.
Abstract: The knowledge of the pathophysiology after traumatic head injury is necessary for adequate and patient-oriented treatment. As the primary insult, which represents the direct mechanical damage, cannot be therapeutically influenced, target of the treatment is the limitation of the secondary damage (delayed non-mechanical damage). It is influenced by changes in cerebral blood flow (hypo- and hyperperfusion), impairment of cerebrovascular autoregulation, cerebral metabolic dysfunction and inadequate cerebral oxygenation. Furthermore, excitotoxic cell damage and inflammation may lead to apoptotic and necrotic cell death. Understanding the multidimensional cascade of secondary brain injury offers differentiated therapeutic options.

1,624 citations


Journal ArticleDOI
TL;DR: B Bland and Altman have provided a modification for analysing repeated measures under stable or changing conditions, where repeated data were collected over a period of time, and this work proposes using random effects models for this purpose.
Abstract: Medical researchers often need to compare two methods of measurement, or a new method with an established one, to determine whether these two methods can be used interchangeably or the new method can replace the established one. – 6 In most of these situations, the ‘true’ value of the measured quantity is unknown. In a series of articles, Bland and Altman – 9 advocated the use of a graphical method to plot the difference scores of two measurements against the mean for each subject and argued that if the new method agrees sufficiently well with the old, the old may be replaced. Here the idea of agreement plays a crucial role in method comparison studies. There are numerous published clinical and laboratory studies evaluating agreement between two measurement methods using Bland–Altman analysis. The original Bland–Altman publication has been cited on more than 11 500 occasions—compelling evidence of its importance in medical research. The Bland–Altman method calculates the mean difference between two methods of measurement (the ‘bias’), and 95% limits of agreement as the mean difference (2 SD) [or more precisely (1.96 SD)]. It is expected that the 95% limits include 95% of differences between the two measurement methods. The plot is commonly called a Bland–Altman plot and the associated method is usually called the Bland–Altman method. The Bland–Altman method can even include estimation of confidence intervals for the bias and limits of agreement, but these are often omitted in research papers. The presentation of the 95% limits of agreement is for visual judgement of how well two methods of measurement agree. The smaller the range between these two limits the better the agreement is. The question of how small is small depends on the clinical context: would a difference between measurement methods as extreme as that described by the 95% limits of agreement meaningfully affect the interpretation of the results? Repeated measurements for each subject are often used in clinical research. Two recent articles in the British Journal of Anaesthesia use such a design. 6 When repeated measures data are available, it is desirable to use all the data to compare the two methods. However, the original Bland–Altman method was developed for two sets of measurements done on one occasion (i.e. independent data), and so this approach is not suitable for repeated measures data. However, as a naı̈ve analysis, it may be used to explore the data because of the simplicity of the method. Examples of the misuse of agreement estimation for repeated measures data can be found readily in the anaesthetic literature: Opdam and colleagues did repeated measurements of cardiac output in six subjects, but incorrectly analysed and plotted 251 paired data sets using the standard Bland–Altman technique. Niedhart and colleagues compared a processed EEG device’s electrode placement on each side of the head in 12 subjects, but analysed and plotted 22 860 paired data sets. Such examples of incorrect use are widespread in the anaesthetic and critical care literature. Bland and Altman have provided a modification for analysing repeated measures under stable or changing conditions, where repeated data were collected over a period of time. As an alternative, we propose using random effects models for this purpose.

527 citations


Journal ArticleDOI
TL;DR: It is proposed that, apart from low coronary risk situations, patients on antiplatelet drugs should continue their treatment throughout surgery, except when bleeding might occur in a closed space, and a therapeutic bridge with shorter-acting anti platelet drugs may be considered.
Abstract: Recent clinical data show that the risk of coronary thrombosis after antiplatelet drugs withdrawal is much higher than that of surgical bleeding if they are continued. In secondary prevention, aspirin is a lifelong therapy and should never be stopped. Clopidogrel is regarded as mandatory until the coronary stents are fully endothelialized, which takes 3 months for bare metal stents, but up to 1 yr for drug-eluting stents. Therefore, interruption of antiplatelet therapy 10 days before surgery should be revised. After reviewing the data on the use of antiplatelet drugs in cardiology and in surgery, we propose an algorithm for the management of patients, based on the risk of myocardial ischaemia and death compared with that of bleeding, for different types of surgery. Even if large prospective studies with a high degree of evidence are still lacking on different antiplatelet regimens during non-cardiac surgery, we propose that, apart from low coronary risk situations, patients on antiplatelet drugs should continue their treatment throughout surgery, except when bleeding might occur in a closed space. A therapeutic bridge with shorter-acting antiplatelet drugs may be considered.

304 citations


Journal ArticleDOI
TL;DR: The surgical stress index (SSI) reacts to surgical nociceptive stimuli and analgesic drug concentration changes during propofol-remifentanil anaesthesia, and stays higher during surgery than before surgery.
Abstract: Background Inadequate analgesia during general anaesthesia may present as undesirable haemodynamic responses. No objective measures of the adequacy of analgesia exist. We aimed at developing a simple numerical measure of the level of surgical stress in an anaesthetized patient. Methods Sixty and 12 female patients were included in the development and validation data sets, respectively. All patients had elective surgery with propofol–remifentanil target controlled anaesthesia. Finger photoplethysmography and electrocardiography waveforms were recorded throughout anaesthesia and various waveform parameters were extracted off-line. Total surgical stress (TSS) for a patient was estimated based on stimulus intensity and remifentanil concentration. The surgical stress index (SSI) was developed to correlate with the TSS estimate in the development data set. The performance of SSI was validated within the validation data set during and before surgery, especially at skin incision and during changes of the predicted remifentanil effect-site concentration. Results SSI was computed as a combination of normalized heart beat interval (HBInorm) and plethysmographic pulse wave amplitude (PPGAnorm): SSI=100–(0.7*PPGAnorm+0.3*HBInorm). SSI increased at skin incision and stayed higher during surgery than before surgery; SSI responded to remifentanil concentration changes and was higher at the lower concentrations of remifentanil. Conclusions SSI reacts to surgical nociceptive stimuli and analgesic drug concentration changes during propofol–remifentanil anaesthesia. Further validation studies of SSI are needed to elucidate its usefulness during other anaesthetic and surgical conditions.

282 citations


Journal ArticleDOI
TL;DR: It is recommended that bolus doses should be used with caution, and further studies should ascertain if oxytocin is equally effective in reducing blood loss when given at a slower rate.
Abstract: Background The cardiovascular effects of oxytocin in animal models and women undergoing Caesarean section include tachycardia, hypotension and decrease in cardiac output. These can be sufficient to cause significant compromise in high-risk patients. We aimed to find a simple way to decrease these risks whilst retaining the benefits of oxytocin in decreasing bleeding after delivery. Method We recruited 30 women undergoing elective Caesarean section. They were randomly allocated to receive 5 u of oxytocin either as a bolus injection (bolus group) or an infusion over 5 min (infusion group). These women had their heart rate and intra-arterial blood pressure recorded every 5 s throughout the procedure. The haemodynamic data, along with the estimated blood loss, were compared between the groups. Results Marked cardiovascular changes occurred in the bolus group; the heart rate increased by 17 (10.7) beats min−1 [mean ( sd )] compared with 10 (9.7) beats min−1 in the infusion group. The mean arterial pressure decreased by 27 (7.6) mm Hg in the bolus group compared with 8 (8.7) mm Hg in the infusion group. There were no differences in the estimated blood loss between the two groups. Conclusion We recommend that bolus doses should be used with caution, and further studies should ascertain if oxytocin is equally effective in reducing blood loss when given at a slower rate.

279 citations


Journal ArticleDOI
TL;DR: There is very little evidence positively in favour of any treatments or packages of early care for head-injured patients; however, prompt, specialist neurocritical care is associated with improved outcome.
Abstract: This review examines the evidence base for the early management of head-injured patients. Traumatic brain injury (TBI) is common, carries a high morbidity and mortality, and has no specific treatment. The pathology of head injury is increasingly well understood. Mechanical forces result in shearing and compression of neuronal and vascular tissue at the time of impact. A series of pathological events may then ensue leading to further brain injury. This secondary injury may be amenable to intervention and is worsened by secondary physiological insults. Various risk factors for poor outcome after TBI have been identified. Most of these are fixed at the time of injury such as age, gender, mechanism of injury, and presenting signs (Glasgow Coma Scale and pupillary signs), but some such as hypotension and hypoxia are potential areas for medical intervention. There is very little evidence positively in favour of any treatments or packages of early care; however, prompt, specialist neurocritical care is associated with improved outcome. Various drugs that target specific pathways in the pathophysiology of brain injury have been the subject of animal and human research, but, to date, none has been proved to be successful in improving outcome.

257 citations


Journal ArticleDOI
TL;DR: A 'restrictive' fluid regimen led to a transient improvement in pulmonary function and postoperative hypoxaemia but no other differences in all-over physiological recovery compared with a 'liberal' [corrected] fluid regimen after fast-track colonic surgery.
Abstract: Background Evidence-based guidelines on optimal perioperative fluid management have not been established, and recent randomized trials in major abdominal surgery suggest that large amounts of fluid may increase morbidity and hospital stay. However, no information is available on detailed functional outcomes or with fast-track surgery. Therefore, we investigated the effects of two regimens of intraoperative fluids with physiological recovery as the primary outcome measure after fast-track colonic surgery. Methods In a double-blind study, 32 ASA I–III patients undergoing elective colonic surgery were randomized to ‘restrictive' (Group 1) or ‘liberal' (Group 2) perioperative fluid administration. Fluid algorithms were based on fixed rates of crystalloid infusions and a standardized volume of colloid. Pulmonary function (spirometry) was the primary outcome measure, with secondary outcomes of exercise capacity (submaximal exercise test), orthostatic tolerance, cardiovascular hormonal responses, postoperative ileus (transit of radio-opaque markers), postoperative nocturnal hypoxaemia, and overall recovery within a well-defined multimodal, fast-track recovery programme. Hospital stay and complications were also noted. Results ‘Restrictive' (median 1640 ml, range 935–2250 ml) compared with ‘liberal' fluid administration (median 5050 ml, range 3563–8050 ml) led to significant improvement in pulmonary function and postoperative hypoxaemia. In contrast, we found significantly reduced concentrations of cardiovascularly active hormones (renin, aldosterone, and angiotensin II) in Group 2. The number of patients with complications was not significantly different between the groups (1 vs 6 patients, P = 0.08). Conclusions A ‘liberal' fluid regimen led to a transient improvement in pulmonary function and postoperative hypoxaemia but no other differences in all-over physiological recovery compared with a ‘restrictive' fluid regimen after fast-track colonic surgery. Since morbidity tended to be increased with the ‘restrictive' fluid regimen, future studies should focus on the effect of individualized ‘goal-directed' fluid administration strategies rather than fixed fluid amounts on postoperative outcome.

255 citations


Journal ArticleDOI
TL;DR: Ultrasound guidance provided a 42% reduction in the MEAV of ropivacaine 0.5% required to block the femoral nerve as compared with the nerve stimulation guidance in patients undergoing knee arthroscopy.
Abstract: Background We tested the hypothesis that ultrasound guidance may reduce the minimum effective anaesthetic volume (MEAV50) of ropivacaine 0.5% required to block the femoral nerve compared with nerve stimulation guidance. Methods After standard premedication and sciatic nerve block were given, 60 patients undergoing knee arthroscopy were randomly allocated to receive a femoral nerve block with ropivacaine 0.5% using either nerve stimulation (group NS, n = 30) or ultrasound (group US, n = 30) guidance. The volume of the injected solution was varied for consecutive patients based on an up-and-down staircase method according to the response of the previous patient. The initial volume was 12 ml. A double-blinded observer evaluated the occurrence of complete loss of pinprick sensation in the femoral nerve distribution, with concomitant block of the quadriceps muscle: positive or negative responses within 30 min after the injection determined a 3 ml decrease or increase for the next patient, respectively. Results The mean ( sd ) MEAV50 for femoral nerve block was 15 (4) ml (95% CI, 7–23 ml) in group US and 26 (4) ml (95% CI, 19–33 ml) in group NS (P = 0.002). The effective dose in 95% of cases (ED95) calculated with probit transformation and logistic regression analysis was 22 ml (95% CI, 13–36 ml) in group US, and 41 ml (95% CI, fs 24–66 ml) in group NS. Conclusions Ultrasound guidance provided a 42% reduction in the MEAV of ropivacaine 0.5% required to block the femoral nerve as compared with the nerve stimulation guidance.

252 citations


Journal ArticleDOI
TL;DR: In this paper, a review of the history, epidemiology, pathophysiology, and natural history of sciatica is presented, and the role of epidural steroid injection in the treatment of this condition is also discussed.
Abstract: Radicular pain in the distribution of the sciatic nerve, resulting from herniation of one or more lumbar intervertebral discs, is a frequent and often debilitating event. The lifetime incidence of this condition is estimated to be between 13% and 40%. Fortunately, the majority of cases resolve spontaneously with simple analgesia and physiotherapy. However, the condition has the potential to become chronic and intractable, with major socio-economic implications. This review discusses the history, epidemiology, pathophysiology, and natural history of sciatica. A Medline search was performed to obtain the published literature on the sciatica, between 1966 and 2006. Hand searches of relevant journals were also performed. Epidemiological factors found to influence incidence of sciatica included increasing height, age, genetic predisposition, walking, jogging (if a previous history of sciatica), and particular physical occupations, including driving. The influence of herniated nucleus pulposus and the probable cytokine-mediated inflammatory response in lumbar and sacral nerve roots is discussed. An abnormal immune response and possible mechanical factors are also proposed as factors that may mediate pain. The ongoing issue of the role of epidural steroid injection in the treatment of this condition is also discussed, as well as potential hazards of this procedure and the direction that future research should take.

247 citations


Journal ArticleDOI
TL;DR: The incidence of postoperative residual curarisation (PORC) was found to be significantly lower after the use of intermediate neuromuscular blocking drugs.
Abstract: We conducted a meta-analysis to examine the effect of intraoperative monitoring of neuromuscular function on the incidence of postoperative residual curarisation (PORC). PORC has been considered present when a patient has a train-of-four (TOF) ratio of < 0.7 or < 0.9. We analysed data from 24 trials (3375 patients) that were published between 1979 and 2005. We excluded data on mivacurium from this meta-analysis because only three studies had examined the incidence of PORC associated with its use. Long- and intermediate-acting neuromuscular blocking drugs had been given to 662 and 2713 patients, respectively. Neuromuscular function was monitored in 823 patients (24.4%). A simple peripheral nerve stimulator was used in 543 patients, and an objective monitor was used in 280. The incidence of PORC was found to be significantly lower after the use of intermediate neuromuscular blocking drugs. We could not demonstrate that the use of an intraoperative neuromuscular function monitor decreased the incidence of PORC.

226 citations


Journal ArticleDOI
TL;DR: Clinical trial data are reviewed describing the efficacy and safety of gabapentin in the setting of perioperative anaesthetic management for chronic post-surgical pain, postoperative nausea and vomiting, and delirium.
Abstract: Gabapentin is a second generation anticonvulsant that is effective in the treatment of chronic neuropathic pain. It was not, until recently, thought to be useful in acute perioperative conditions. However, a growing body of evidence suggests that perioperative administration is efficacious for postoperative analgesia, preoperative anxiolysis, attenuation of the haemodynamic response to laryngoscopy and intubation, and preventing chronic post-surgical pain, postoperative nausea and vomiting, and delirium. This article reviews the clinical trial data describing the efficacy and safety of gabapentin in the setting of perioperative anaesthetic management.

Journal ArticleDOI
TL;DR: Ulasound guidance for sciatic and femoral nerve blocks in children increased the duration of sensory blockade in comparison with nerve stimulator guidance, and prolonged sensory blockade was achieved with smaller volumes of local anaesthetic when using ultrasound guidance.
Abstract: Background Recent studies have shown that ultrasound guidance for paediatric regional anaesthesia can improve the quality of upper extremity and neuraxial blocks. We therefore investigated whether ultrasound guidance for sciatic and femoral nerve blocks prolongs sensory blockade in comparison with nerve stimulator guidance in children. Methods Forty-six children scheduled for surgery of one lower extremity were randomized to receive a sciatic and femoral nerve block under either ultrasound or nerve stimulator guidance. After induction of general anaesthesia, the blocks were performed using an ultrasound-guided multiple injection technique until the nerves were surrounded by levobupivacaine, or by nerve stimulator guidance using a predefined dose of 0.3 ml kg −1 of levobupivacaine. An increase in heart rate of more than 15% of baseline during surgery defined a failed block. The duration of the block was determined from the injection of local anaesthetic to the time when the patient received the first postoperative analgesic. Results Two blocks in the nerve stimulator group failed. There were no failures in the ultrasound group. The duration of analgesia was longer in the ultrasound group mean (sd) 508 (178) vs 335 (169) min ( P vs 0.3 ml kg −1 ( P vs 0.3 ml kg −1 ( P Conclusions Ultrasound guidance for sciatic and femoral nerve blocks in children increased the duration of sensory blockade in comparison with nerve stimulator guidance. Prolonged sensory blockade was achieved with smaller volumes of local anaesthetic when using ultrasound guidance.

Journal ArticleDOI
TL;DR: Members of ICU teams have divergent perceptions of their communication with one another, and communication openness among team members is also associated with the degree to which they understand patient care goals.
Abstract: Background Patient safety research has shown poor communication among intensive care unit (ICU) nurses and doctors to be a common causal factor underlying critical incidents in intensive care. This study examines whether ICU doctors and nurses have a shared perception of interdisciplinary communication in the UK ICU. Methods Cross-sectional survey of ICU nurses and doctors in four UK hospitals using a previously established measure of ICU interdisciplinary collaboration. Results A sample of 48 doctors and 136 nurses (47% response rate) from four ICUs responded to the survey. Nurses and doctors were found to have differing perceptions of interdisciplinary communication, with nurses reporting lower levels of communication openness between nurses and doctors. Compared with senior doctors, trainee doctors also reported lower levels of communication openness between doctors. A regression path analysis revealed that communication openness among ICU team members predicted the degree to which individuals reported understanding their patient care goals (adjR 2 = 0.17). It also showed that perceptions of the quality of unit leadership predicted open communication. Conclusions Members of ICU teams have divergent perceptions of their communication with one another. Communication openness among team members is also associated with the degree to which they understand patient care goals. It is necessary to create an atmosphere where team members feel they can communicate openly without fear of reprisal or embarrassment.

Journal ArticleDOI
TL;DR: This review will discuss the intensive care management of severe TBI with emphasis on the specific measures directed at the control of intracranial pressure and CPP.
Abstract: Traumatic brain injury (TBI) is a major cause of morbidity and mortality worldwide. The modern management of severe TBI has fallen into the domain of a multidisciplinary team led by neurointensivists, neuroanaesthetists, and neurosurgeons and is based on the avoidance of secondary injury, maintenance of cerebral perfusion pressure (CPP), and optimization of cerebral oxygenation. In this review, we will discuss the intensive care management of severe TBI with emphasis on the specific measures directed at the control of intracranial pressure and CPP.

Journal ArticleDOI
TL;DR: It is concluded that superficial/intermediate block is safer than any method that employs a deep injection, and the higher rate of conversion to general anaesthesia with the deep/combined block may have been influenced by the higher incidence of direct complications.
Abstract: Carotid endarterectomy is commonly conducted under regional (deep, superficial, intermediate, or combined) cervical plexus block, but it is not known if complication rates differ. We conducted a systematic review of published papers to assess the complication rate associated with superficial (or intermediate) and deep (or combined deep plus superficial/intermediate). The null hypothesis was that complication rates were equal. Complications of interest were: (1) serious complications related to the placement of block, (2) incidence of conversion to general anaesthesia, and (3) serious systemic complications of the surgical-anaesthetic process. We retrieved 69 papers describing a total of 7558 deep/combined blocks and 2533 superficial/intermediate blocks. Deep/combined block was associated with a higher serious complication rate related to the injecting needle when compared with the superficial/intermediate block (odds ratio 2.13, P = 0.006). The conversion rate to general anaesthesia was also higher with deep/combined block (odds ratio 5.15, P < 0.0001), but there was an equivalent incidence of other systemic serious complications (odds ratio 1.13, P = 0.273; NS). We conclude that superficial/intermediate block is safer than any method that employs a deep injection. The higher rate of conversion to general anaesthesia with the deep/combined block may have been influenced by the higher incidence of direct complications, but may also suggest that the superficial/combined block provides better analgesia during surgery.

Journal ArticleDOI
TL;DR: PH is an important predictor of adverse cardiopulmonary outcome in non-cardiac surgery as reflected by markedly increased postoperative complications, especially in patients with coexistent high-risk clinical and surgical characteristics.
Abstract: Background Whether and how pulmonary hypertension (PH) impacts perioperative outcome in non-cardiac surgery is incompletely understood. Methods From November 1999, all patients undergoing non-cardiac, non-local anaesthetic surgery and ever examined by echocardiography within 30 days before surgery were screened. Those having echocardiographic pulmonary artery systolic pressure >70 mm Hg were enrolled provided they were not already intubated. Case-matched peers with normal pulmonary pressures served as controls. Perioperative outcomes were compared between the two groups, and predictors of adverse perioperative outcomes were investigated by multivariate logistic regression analysis. Results From November 1999 to August 2004, a total of 62 patients (male 38, mean age 67 yr) with PH were found. Compared with the case-matched controls, patients with PH experienced equivalently smooth operative courses, but significantly more frequent postoperative heart failure (9.7 vs 0%, P = 0.028), delayed tracheal extubation (21 vs 3%, P = 0.004), and in-hospital deaths (9.7 vs 0%, P = 0.028). Multivariate regression analysis identified emergency surgery [odds ratio (OR), 44.738; P = 0.028], coronary artery disease (CAD; OR, 9.933; P = 0.042), and systolic pulmonary artery pressure (OR, 1.101; P = 0.026) as independent predictors of postoperative mortality and surgery-specific cardiac risk level (OR, 6.791; P = 0.033) and CAD (OR 6.546, P = 0.017) as predictors of morbidity. Conclusion PH is an important predictor of adverse cardiopulmonary outcome in non-cardiac surgery as reflected by markedly increased postoperative complications, especially in patients with coexistent high-risk clinical and surgical characteristics.

Journal ArticleDOI
TL;DR: The Worthing PSS was developed from the regression coefficients associated with each variable and showed good discrimination with an area under the receiver operating characteristic curve, 0.74, excluding age as a variable.
Abstract: Background Several physiological scoring systems (PSS) have been proposed for identifying those at risk of deterioration. However, the chosen specific physiological values chosen and the scores allocated have not been prospectively validated. In this study, we investigate the relative contributions of the ventilatory frequency, heart rate, arterial pressure, temperature, oxygen saturation, and conscious level to mortality in order to devise a robust scoring system. All data were collected on admission to the emergency unit. Precise ‘intervention-calling scores’ could then be derived to trigger interventions. Methods Our observational, population-based single-centred study took place in a 602-bedded district general hospital. Patients admitted to the emergency care unit at Worthing general hospital during an initial study period between July and November 2003 (n = 3184) and a further validation period between October and November 2005 (n = 1102) were included. Results Multivariate logistic regression analysis demonstrated that a ventilatory frequency ≥20 min−1, heart rate ≥102 min−1, systolic blood pressure ≤99 mm Hg, temperature Conclusions A simple validated scoring system to predict mortality in medical patients with precise ‘intervention-calling scores’ has been developed.

Journal ArticleDOI
TL;DR: The performance of the FloTrac/Vigileo system, the PiCCOplus, and the Vigilance CCO monitoring for CO measurement were comparable when tested against intermittent thermodilution in patients undergoing elective cardiac surgery.
Abstract: Background Assessment of cardiac output (CO) by the FloTrac/Vigileo™ system may offer a less invasive means of determining the CO than either the pulmonary artery catheter (PAC) or the PiCCOplus™ system. The aim of this study was to compare CO measurements made using the FloTrac/Vigileo™ system with upgraded software (FCO, Edwards Lifesciences, Irvine CA, USA), the PiCCOplus™ system (PCO, Pulsion Medical Systems, Munich, Germany) and continuous CO monitoring using a PAC (CCO; Vigilance™ monitoring, Edwards Lifesciences, Irvine CA, USA) with intermittent pulmonary artery thermodilution (ICO). The study was conducted in patients undergoing elective cardiac surgery. Methods Thirty-one patients with preserved left ventricular function were enrolled. CCO, FCO, and PCO were recorded in the perioperative period at six predefined time points after achieving stable haemodynamic conditions; ICO was determined from the mean of three bolus injections. Bland–Altman analysis was used to compare CCO, FCO, and PCO with ICO. Results Bland–Altman analysis revealed a comparable mean bias and limits of agreement for all tested continuous CO monitoring devices using ICO as reference method. Agreement for all devices decreased in the postoperative period. Conclusion The performance of the FloTrac/Vigileo™ system, the PiCCOplus™, and the Vigilance™ CCO monitoring for CO measurement were comparable when tested against intermittent thermodilution in patients undergoing elective cardiac surgery.

Journal ArticleDOI
TL;DR: In critically ill surgical patients, plasma selenium concentrations are generally low with a greater decrease during the ICU stay in patients with organ failure, especially when attributed to infection.
Abstract: Background. Selenium plays an important role in defence against acute illness. We investigated, in intensive care unit (ICU) patients, the time course of plasma selenium concentrations and their relationship to systemic inflammatory response syndrome (SIRS), organ dysfunction/ failure, infection, and ICU outcome. Methods. Plasma selenium and laboratory indices of organ dysfunction/failure, tissue inflammation, and infection were measured daily during the ICU stay in 60 consecutive ICU patients, 15 in each of four a priori defined subgroups: ICU controls (no SIRS); uncomplicated SIRS; severe SIRS; and severe sepsis/septic shock. Results. Plasma selenium concentrations were below standard values for healthy subjects (74 mg litre 21 ) in 55 patients (92%). Selenium concentrations decreased during the ICU stay in all groups, except controls, to a minimum value that was lower in patients with organ failure, particularly in those with infection. The minimum plasma selenium was inversely correlated to admission Acute Physiology and Chronic Health Evaluation II and Simplified Acute Physiology System II scores, indicators of inflammation, and the maximal degree of organ dysfunction/ failure during the ICU stay. Plasma selenium was positively correlated with minimum platelet count, minimum plasma antithrombin activity, and protein C activity. In a receiver operator characteristic analysis, SAPS II score [area under the curve (AUC)¼0.903] and minimum selenium concentration (AUC¼0.867) were the strongest predictive factors for ICU mortality. Conclusions. In critically ill surgical patients, plasma selenium concentrations are generally low with a greater decrease during the ICU stay in patients with organ failure, especially when attributed to infection. Lower plasma selenium concentrations are associated with more tissue damage, the presence of infection or organ dysfunction/failure, and increased ICU mortality.

Journal ArticleDOI
TL;DR: These data indicate that pro-inflammatory reactions during OLV were influenced by the type of general anaesthesia, and different patterns of alveolar cytokines may be a result of increased granulocyte recruitment during propofol anaesthesia.
Abstract: Background One-lung ventilation (OLV) induces a pro-inflammatory response including cytokine release and leucocyte recruitment in the ventilated lung. Whether volatile or i.v. anaesthetics differentially modulate the alveolar inflammatory response to OLV is unclear. Methods Thirty patients, ASA II or III, undergoing open thoracic surgery were randomized to receive either propofol 4 mg kg−1 h−1 (n = 15) or 1 MAC desflurane in air (n = 15) during thoracic surgery. Analgesia was provided by i.v. infusion of remifentanil (0.25 μg kg−1 min−1) in both groups. The patients were mechanically ventilated according to a standard protocol during two-lung ventilation and OLV. Fibre optic bronchoalveolar lavage (BAL) of the ventilated lung was performed before and after OLV and 2 h postoperatively. Alveolar cells, protein, tumour necrosis factor α (TNFα), interleukin (IL)-8, soluble intercellular adhesion molecule-1 (sICAM), IL10, and polymorphonuclear (PMN) elastase were determined in the BAL fluid. Data were analysed by parametric or non-parametric tests, as indicated. Results In both groups, an increase in pro-inflammatory markers was found after OLV and 2 h postoperatively; however, the fraction of alveolar granulocytes (median 63.7 vs 31.1%, P Conclusions These data indicate that pro-inflammatory reactions during OLV were influenced by the type of general anaesthesia. Different patterns of alveolar cytokines may be a result of increased granulocyte recruitment during propofol anaesthesia.

Journal ArticleDOI
TL;DR: In cardiac surgery patients, CO measured by a new semi-invasive arterial pressure waveform analysis device showed only moderate agreement with intermittent pulmonary artery thermodilution measurement.
Abstract: Institutional Review Board (IRB) approval of this research could not be verified during an investigation by the Landesarztekammer Rheinland-Pfalz (the State Medical Association of Rheinland-Pfalz in Germany). As a result, this article has been retracted, in accordance with the Journal’s regulations, at the request of the Directors and Board of the British Journal of Anaesthesia. Lack of IRB approval means that the research was unethical, and that IRB approval for the research was misrepresented in the published article. It does not mean that the research results per se are fraudulent. For further information please see Retraction .

Journal ArticleDOI
TL;DR: Aprepitant was significantly more effective than ondansetron for preventing vomiting at 24 and 48 h after surgery, and in reducing nausea severity in the first 48H after surgery.
Abstract: Background The neurokinin1 antagonist aprepitant is effective for prevention of chemotherapy-induced nausea and vomiting. We compared aprepitant with ondansetron for prevention of postoperative nausea and vomiting. Methods Nine hundred and twenty-two patients receiving general anaesthesia for major abdominal surgery were assigned to receive a single preoperative dose of oral aprepitant 40 mg, oral aprepitant 125 mg, or i.v. ondansetron 4 mg in a randomized, double-blind trial. Vomiting episodes, use of rescue therapy, and nausea severity (verbal rating scale) were documented for 48 h after surgery. Primary efficacy endpoints were complete response (no vomiting and no use of rescue therapy) 0–24 h after surgery and no vomiting 0–24 h after surgery. The secondary endpoint was no vomiting 0–48 h after surgery. Results Aprepitant at both doses was non-inferior to ondansetron for complete response 0–24 h after surgery (64% for aprepitant 40 mg, 63% for aprepitant 125 mg, and 55% for ondansetron, lower bound of 1-sided 95% CI > 0.65), superior to ondansetron for no vomiting 0–24 h after surgery (84% for aprepitant 40 mg, 86% for aprepitant 125 mg, and 71% for ondansetron; P Conclusions Aprepitant was non-inferior to ondansetron in achieving complete response for 24 h after surgery. Aprepitant was significantly more effective than ondansetron for preventing vomiting at 24 and 48 h after surgery, and in reducing nausea severity in the first 48 h after surgery. Aprepitant was generally well tolerated.

Journal ArticleDOI
TL;DR: In this article, a nested case-control study was conducted in 117 UK veterinary centres and the overall risk of anaesthetic and sedation-related death was 0.24% (95% CI 0.20-0.27).
Abstract: Background Cats are commonly anaesthetized in veterinary practice, but recent figures describing the frequency of or risk factors for anaesthetic-related death are not available. The aims of this study were to address these deficiencies. Methods A nested case–control study was undertaken in 117 UK veterinary centres. All anaesthetic and sedation procedures and anaesthetic and sedation-related deaths (i.e. ‘cases') occurring within 48 h were recorded. Details of patient, procedure, and perioperative management were recorded for all cases and randomly selected non-deaths (controls). A detailed statistical model of factors associated with anaesthetic and sedation-related death was constructed. Results Between June 2002 and June 2004, 175 deaths were classified as anaesthetic and sedation-related and 14 additional deaths (with insufficient information to be excluded) were included for the estimation of risk. During the study, 79 178 anaesthetic and sedation procedures were recorded and the overall risk of anaesthetic and sedation-related death was 0.24% (95% CI 0.20–0.27). Factors associated with increased odds of anaesthetic-related death were poor health status (ASA physical status classification), increasing age, extremes of weight, increasing procedural urgency and complexity, endotracheal intubation, and fluid therapy. Pulse monitoring and pulse oximetry were associated with reduced odds. Conclusions The risk of anaesthetic-related death in cats appears to have decreased since the last published study in the UK. The results should aid the preoperative identification of cats at greatest risk. Greater care with endotracheal intubation and fluid administration are recommended, and pulse and pulse oximetry monitoring should be routinely implemented in cats.

Journal ArticleDOI
TL;DR: In this observational study, haematological cancer, the presence of sepsis, cardiovascular failure, and baseline renal function as assessed by the SOFA score were independent risk factors for the subsequent need for RRT in the ICU.
Abstract: BACKGROUND: The influence of hydroxyethyl starch (HES) solutions on renal function is controversial. We investigated the effect of HES administration on renal function in critically ill patients enrolled in a large multicentre observational European study. METHODS: All adult patients admitted to the 198 participating intensive care units (ICUs) during a 15-day period were enrolled. Prospectively collected data included daily fluid administration, urine output, sequential organ failure assessment (SOFA) score, serum creatinine levels, and the need for renal replacement therapy (RRT) during the ICU stay. RESULTS: Of 3147 patients, 1075 (34%) received HES. Patients who received HES were older [mean (SD): 62 (SD 17) vs 60 (18) years, P = 0.022], more likely to be surgical admissions, had a higher incidence of haematological malignancy and heart failure, higher SAPS II [40.0 (17.0) vs 34.7 (16.9), P 1 (P < 0.01 for renal SOFA 2, 3, and 4 with renal SOFA = 0 as a reference) were all associated with a higher need for RRT. CONCLUSIONS: In this observational study, haematological cancer, the presence of sepsis, cardiovascular failure, and baseline renal function as assessed by the SOFA score were independent risk factors for the subsequent need for RRT in the ICU. The administration of HES had no influence on renal function or the need for RRT in the ICU.

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TL;DR: Pulse contour analysis-derived CO (Vigileo system) underestimates CO(TPID) and is not as reliable as transpulmonary thermodilution in septic patients.
Abstract: Background Recently, continuous monitoring of cardiac output (CO) based on pulse contour analysis (Vigileo®) has been introduced into practice. In this clinical study, we evaluated the accuracy of this system by comparing it with the transpulmonary thermodilution technique (TPID) in septic patients. Methods We studied 24 mechanically ventilated patients with septic shock (16 male, 8 female, age 26–77 yr) receiving treatment with norepinephrine who for clinical indication underwent haemodynamic monitoring by the transpulmonary thermodilution technique using a PiCCO®plus system (Pulsion Medical Systems, Munich, Germany). In parallel, arterial pulse contour was applied using the femoral arterial pressure curve (FloTrac® pressure sensor, Vigileo® monitor, Edwards Lifesciences, Irvine, USA). After baseline measurement, mean arterial pressure was elevated by increasing norepinephrine dosage, and CO was measured again before mean arterial pressure was reduced back to baseline levels. Fluid status and ventilator settings remained unchanged throughout. At each time point, CO by transpulmonary thermodilution was calculated from three central venous bolus injections of 15 ml of saline ( Results Overall, CO was 6.7 (sd 1.8) (3.2–10.1) litre min−1 for CO(TPID) and 6.2 (2.4) (3.0–17.6) litre min−1 for CO(Vigileo®). Linear regression revealed: CO(Vigileo®) = 1.54 + 0.72 × CO(TPID) litre min−1, r2 = 0.26 (P Conclusions Pulse contour analysis-derived CO (Vigileo® system) underestimates CO(TPID) and is not as reliable as transpulmonary thermodilution in septic patients.

Journal ArticleDOI
TL;DR: The surgical stress index (SSI) is based on a sum of the normalized pulse beat interval (PBI) and the pulse wave amplitude (PPGA) time series of the photoplethysmography as mentioned in this paper.
Abstract: Background The surgical stress index (SSI) is based on a sum of the normalized pulse beat interval (PBI) and the pulse wave amplitude (PPGA) time series of the photoplethysmography As a measure of the nociception–anti-nociception balance in response to a standardized pain stimulus, SSI was compared with EEG changes in state and response entropy (SE and RE), PPGA, and heart rate (HR) during various targeted pseudo-steady-state concentrations of propofol and remifentanil Methods Forty ASA I patients were allocated to one of the four groups to receive a remifentanil step-up/-down effect-compartment target-controlled infusion (Ceremi )o f 0, 2, 6, 2, 0n g ml 21 , or 6, 2, 0, 2, 6 ng ml 21 , and an effect-compartment target-controlled propofol infusion (Ceprop) to keep the SE between 30 and 50 or 15 and 30, respectively At each steady-state Ceremi, maximum change in SSI, SE, RE, PPGA, and HR after a noxious stimulus was compared with the baseline value A correlation and prediction probability (PK) with Ceprop and Ceremi was measured Results Static and dynamic values of SSI correlated to Ceremi better than SE, RE, HR, and PPGA SSI was independent of Ceprop, in contrast to SE and RE The PK for Ceremi both before and during a noxious stimulus was better with SSI

Journal ArticleDOI
TL;DR: PMA and PNA contribute to the inter-individual variability of propofol clearance with very fast maturation of clearance in neonatal life and implicates that preterm neonates and neonates in the first week of postnatal life are at an increased risk for accumulation during either intermittent bolus or continuous administration of prop ofol.
Abstract: Background To document covariates which contribute to inter-individual variability in propofol pharmacokinetics in preterm and term neonates. Methods Population pharmacokinetics were estimated (non-linear mixed effect modelling) based on the arterial blood samples collected in (pre)term neonates after i.v. bolus administration of propofol (3 mg kg−1, 10 s). Covariate analysis included postmenstrual age (PMA), postnatal age (PNA), gestational age, weight, and serum creatinine. Results Two hundred and thirty-five arterial concentration–time points were collected in 25 neonates. Median weight was 2930 (range 680–4030) g, PMA 38 (27–43) weeks, and PNA 8 (1–25) days. In a three-compartment model, PMA was the most predictive covariate for clearance (P 0.001). Conclusions PMA and PNA contribute to the inter-individual variability of propofol clearance with very fast maturation of clearance in neonatal life. This implicates that preterm neonates and neonates in the first week of postnatal life are at an increased risk for accumulation during either intermittent bolus or continuous administration of propofol.

Journal ArticleDOI
TL;DR: The implementation of NICE guidelines has been associated with a significant reduction in complication rates in the authors' tertiary referral centre, and it is imperative that routine use of US guidance becomes more widespread.
Abstract: Background The National Institute for Clinical Excellence (NICE) guidelines of 2002 recommended the use of ultrasound (US) for central venous catheterization in order to minimize complications associated with central line placement. An ongoing audit of line placement by anaesthetists in the theatre complex of a tertiary referral centre looked at the associated complication rates. The objective of the study was to compare complication rates pre- and post-implementation of NICE guidelines. Methods This prospective, single centre audit looked at all patients in whom a central venous catheter was placed for surgery. Complication rates were assessed for procedures that were performed pre- and post-implementation of NICE guidelines. In total, 438 patients were identified for the study, and the procedures were performed either by trainee or by consultant anaesthetists. Results The pre- and post-implementation complication rates were 10.5% (16/152) and 4.6% (13/284), respectively, representing an absolute risk reduction of 5.9% (95% CI 0.5–11.3%). Comparison of those procedures in which US was used when compared with the landmark technique after implementation found a reduction of 6.9% in complications (95% CI 1.4–12.4%). The reduction in complication rates was larger for specialist registrars than for consultants (11.2% vs 1.6%). Conclusions The implementation of NICE guidelines has been associated with a significant reduction in complication rates in our tertiary referral centre. In the light of the cross-speciality evidence of US superiority and our results, it is imperative that routine use of US guidance becomes more widespread.

Journal ArticleDOI
TL;DR: This US-guided approach of the SCV offers a new possibility for central venous catheterization in children and seems promising for children less than 10 kg and probably also for older children.
Abstract: BACKGROUND: Central venous cannulation in infants remains challenging even for experienced paediatric anaesthesiologists. Ultrasound (US)-guidance techniques are proven to be safer for internal jugular vein catheterization. But the subclavian vein (SCV) is often the preferred site for long-term central venous catheterization in children. We describe a novel US-guided approach for SCV cannulation in infants and children. METHODS: The principle of this technique is to place the US probe at the supraclavicular level to obtain a longitudinal view of the SCV, and to gain access to the vein via the usual infraclavicular route to cannulate it under ultrasonic control. Details and pitfalls of this technique are described. The prospectively collected results of our first 25 punctures are reported. RESULTS: Patients' weight and age range were 2.2-27 kg and 1 day to 9 yr, respectively: 76% of the children weighed less than 10 kg. The success rate at the first attempt was 84% and 100% after two attempts. An asymptomatic thrombus in the SCV could also be detected with this technique. CONCLUSIONS: This US-guided approach of the SCV offers a new possibility for central venous catheterization in children. This technique seems promising for children less than 10 kg and probably also for older children. It provides good quality needle guidance and allows to check the vessel patency before puncture.

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TL;DR: The evidence available for the perioperative strategies aimed at reducing adverse outcomes in a number of different clinical scenarios are examined.
Abstract: The utility of interventional cardiology has developed significantly over the last two decades with the introduction of coronary angioplasty and stenting, with the associated antiplatelet medications. Acute coronary stent occlusion carries a high morbidity and mortality, and the adoption of therapeutic strategies for prophylaxis against stent thrombosis has major implications for surgeons and anaesthetists involved in the management of these patients in the perioperative period. Currently, there is limited published information to guide the clinician in the optimal care of patients who have had coronary stents inserted when they present for non-cardiac surgery. This review examines the available literature on the perioperative management of these patients. A number of key issues are identified: the role of surgery vs percutaneous coronary intervention for coronary revascularization in the preoperative period; the different types of coronary stents currently available; the emerging issues related to drug-eluting stents; the pathophysiology of coronary stent occlusion; and the recommended antiplatelet regimes that the patient with a coronary stent will be receiving. The role of preoperative platelet function testing is also discussed, and the various available tests are listed. Appropriate management by all the clinicians involved with patients with coronary stents undergoing a variety of non-cardiac surgical procedures is essential to avoid a high incidence of postoperative cardiac mortality and morbidity. The review examines the evidence available for the perioperative strategies aimed at reducing adverse outcomes in a number of different clinical scenarios.