Showing papers in "BJA: British Journal of Anaesthesia in 2011"
TL;DR: The incidence of death and brain damage from airway management during general anaesthesia is low, and statistical analysis of the distribution of reports suggests as few as 25% of relevant incidents may have been reported, providing an indication of the lower limit for incidence of such complications.
Abstract: Results. Of 184 reports meeting inclusion criteria, 133 related to general anaesthesia: 46 events per million general anaesthetics [95% confidence interval (CI) 38 ‐54] or one per 22 000 (95% CI 1 per 26‐ 18 000). Anaesthesia events led to 16 deaths and three episodes of persistent brain damage: a mortality rate of 5.6 per million general anaesthetics (95% CI 2.8‐ 8.3): one per 180 000 (95% CI 1 per 352‐120 000). These estimates assume that all such cases were captured. Rates of death and brain damage for different airway devices (facemask, supraglottic airway, tracheal tube) varied little. Airway management was considered good in 19% of assessable anaesthesia cases. Elements of care were judged poor in three-quarters: in only three deaths was airway management considered exclusively good. Conclusions. Although these data suggest the incidence of death and brain damage from airway management during general anaesthesia is low, statistical analysis of the distribution of reports suggests as few as 25% of relevant incidents may have been reported. It therefore provides an indication of the lower limit for incidence of such complications. The review of airway management indicates that in a majority of cases, there is ‘room for improvement’.
1,610 citations
TL;DR: The project findings suggest avoidable deaths due to airway complications occur in ICU and the ED, and repeated gaps in care that include poor identification of at-risk patients, poor or incomplete planning, inadequate provision of skilled staff and equipment to manage these events successfully are identified.
Abstract: Background The Fourth National Audit Project of the Royal College of Anaesthetists and Difficult Airway Society (NAP4) was designed to identify and study serious airway complications occurring during anaesthesia, in intensive care unit (ICU) and the emergency department (ED). Methods Reports of major complications of airway management (death, brain damage, emergency surgical airway, unanticipated ICU admission, prolonged ICU stay) were collected from all National Health Service hospitals over a period of 1 yr. An expert panel reviewed inclusion criteria, outcome, and airway management. Results A total of 184 events met inclusion criteria: 36 in ICU and 15 in the ED. In ICU, 61% of events led to death or persistent neurological injury, and 31% in the ED. Airway events in ICU and the ED were more likely than those during anaesthesia to occur out-of-hours, be managed by doctors with less anaesthetic experience and lead to permanent harm. Failure to use capnography contributed to 74% of cases of death or persistent neurological injury. Conclusions At least one in four major airway events in a hospital are likely to occur in ICU or the ED. The outcome of these events is particularly adverse. Analysis of the cases has identified repeated gaps in care that include: poor identification of at-risk patients, poor or incomplete planning, inadequate provision of skilled staff and equipment to manage these events successfully, delayed recognition of events, and failed rescue due to lack of or failure of interpretation of capnography. The project findings suggest avoidable deaths due to airway complications occur in ICU and the ED.
784 citations
TL;DR: Evidence suggests that the utility of topical capsaicin may extend beyond painful peripheral neuropathies, and includes longer duration of effect, patient compliance, and low risk for systemic effects or drug–drug interactions.
Abstract: Topical capsaicin formulations are used for pain management. Safety and modest efficacy of low-concentration capsaicin formulations, which require repeated daily self-administration, are supported by meta-analyses of numerous studies. A high-concentration capsaicin 8% patch (Qutenza™) was recently approved in the EU and USA. A single 60-min application in patients with neuropathic pain produced effective pain relief for up to 12 weeks. Advantages of the high-concentration capsaicin patch include longer duration of effect, patient compliance, and low risk for systemic effects or drug–drug interactions. The mechanism of action of topical capsaicin has been ascribed to depletion of substance P. However, experimental and clinical studies show that depletion of substance P from nociceptors is only a correlate of capsaicin treatment and has little, if any, causative role in pain relief. Rather, topical capsaicin acts in the skin to attenuate cutaneous hypersensitivity and reduce pain by a process best described as ‘defunctionalization’ of nociceptor fibres. Defunctionalization is due to a number of effects that include temporary loss of membrane potential, inability to transport neurotrophic factors leading to altered phenotype, and reversible retraction of epidermal and dermal nerve fibre terminals. Peripheral neuropathic hypersensitivity is mediated by diverse mechanisms, including altered expression of the capsaicin receptor TRPV1 or other key ion channels in affected or intact adjacent peripheral nociceptive nerve fibres, aberrant re-innervation, and collateral sprouting, all of which are defunctionalized by topical capsaicin. Evidence suggests that the utility of topical capsaicin may extend beyond painful peripheral neuropathies.
543 citations
TL;DR: There is still little conclusive evidence of any beneficial effect of systemic antioxidant supplementation in patients with sepsis and organ dysfunction, but it has been suggested that antioxidant therapy delivered specifically to mitochondria may be useful.
Abstract: Sepsis-related organ dysfunction remains the most common cause of death in the intensive care unit (ICU), despite advances in healthcare and science. Marked oxidative stress as a result of the inflammatory responses inherent with sepsis initiates changes in mitochondrial function which may result in organ damage. Normally, a complex system of interacting antioxidant defences is able to combat oxidative stress and prevents damage to mitochondria. Despite the accepted role that oxidative stress-mediated injury plays in the development of organ failure, there is still little conclusive evidence of any beneficial effect of systemic antioxidant supplementation in patients with sepsis and organ dysfunction. It has been suggested, however, that antioxidant therapy delivered specifically to mitochondria may be useful.
467 citations
TL;DR: It is suggested that erythropoiesis-stimulating agents be used for anaemic patients in whom nutritional deficiencies have been ruled out, corrected, or both and that nutritional deficiencies be treated.
Abstract: Previously undiagnosed anaemia is common in elective orthopaedic surgical patients and is associated with increased likelihood of blood transfusion and increased perioperative morbidity and mortality. A standardized approach for the detection, evaluation, and management of anaemia in this setting has been identified as an unmet medical need. A multidisciplinary panel of physicians was convened by the Network for Advancement of Transfusion Alternatives (NATA) with the aim of developing practice guidelines for the detection, evaluation, and management of preoperative anaemia in elective orthopaedic surgery. A systematic literature review and critical evaluation of the evidence was performed, and recommendations were formulated according to the method proposed by the Grades of Recommendation Assessment, Development and Evaluation (GRADE) Working Group. We recommend that elective orthopaedic surgical patients have a haemoglobin (Hb) level determination 28 days before the scheduled surgical procedure if possible (Grade 1C). We suggest that the patient's target Hb before elective surgery be within the normal range, according to the World Health Organization criteria (Grade 2C). We recommend further laboratory testing to evaluate anaemia for nutritional deficiencies, chronic renal insufficiency, and/or chronic inflammatory disease (Grade 1C). We recommend that nutritional deficiencies be treated (Grade 1C). We suggest that erythropoiesis-stimulating agents be used for anaemic patients in whom nutritional deficiencies have been ruled out, corrected, or both (Grade 2A). Anaemia should be viewed as a serious and treatable medical condition, rather than simply an abnormal laboratory value. Implementation of anaemia management in the elective orthopaedic surgery setting will improve patient outcomes.
460 citations
TL;DR: The MTC found that there is a decrease in 24 h morphine consumption when paracetamol, NSAID, or COX-2 inhibitors are given in addition to PCA morphine after surgery, with no clear difference between them.
Abstract: Non-opioid analgesics, paracetamol, non-steroidal anti-inflammatory drugs (NSAIDs), or cyclo-oxygenase 2 (COX-2) inhibitors are often given along with morphine as part of multimodal analgesia after major surgery. We have undertaken a systematic review and a mixed treatment comparison (MTC) analysis in order to determine explicitly which class of non-opioid analgesic, paracetamol, NSAIDs, or COX-2 inhibitors is the most effective in reducing morphine consumption and morphine-related adverse effects. Sixty relevant studies were identified. The MTC found that when paracetamol, NSAIDs, or COX-2 inhibitors were added to patient-controlled analgesia (PCA) morphine, there was a statistically significant reduction in morphine consumption: paracetamol [mean difference (MD) -6.34 mg; 95% credibility interval (CrI) -9.02, -3.65], NSAIDs (MD -10.18; 95% CrI -11.65, -8.72), and COX-2 inhibitors (MD -10.92; 95% CrI -12.77, -9.08). There was a significant reduction in nausea and postoperative nausea and vomiting with NSAIDs compared with placebo (odds ratio 0.70; 95% CrI 0.53, 0.88) but not for paracetamol or COX-2 inhibitors, nor for NSAIDs compared with paracetamol or COX-2 inhibitors. There was no statistically significant difference in sedation between any intervention and comparator. On the basis of six trials (n=695), 2.4% of participants receiving an NSAID experienced surgical-related bleeding compared with 0.4% with placebo. The MTC found that there is a decrease in 24 h morphine consumption when paracetamol, NSAID, or COX-2 inhibitors are given in addition to PCA morphine after surgery, with no clear difference between them. Similarly, the benefits in terms of reduction in morphine-related adverse effects do not strongly favour one of the three non-opioid analgesics.
414 citations
TL;DR: This study suggests that HFNCs reduce respiratory rate and improve oxygenation by increasing both EELV and tidal volume and are most beneficial in patients with higher BMIs.
Abstract: † In this study of patients after cardiac surgery, HFNC increased end-expiratory lung impedance, suggesting increased lung volumes and functional residual capacity. † Oxygenation improved and the benefits were greatest in patients with high BMIs. † Further data are required to assess the clinical significance of these data. Background. High-flow nasal cannulae (HFNCs) create positive oropharyngeal airway pressure, but it is unclear how their use affects lung volume. Electrical impedance tomography allows the assessment of changes in lung volume by measuring changes in lung impedance. Primary objectives were to investigate the effects of HFNC on airway pressure (Paw) and end-expiratory lung volume (EELV) and to identify any correlation between the two. Secondary objectives were to investigate the effects of HFNC on respiratory rate, dyspnoea, tidal volume, and oxygenation; and the interaction between BMI and EELV. Methods. Twenty patients prescribed HFNC post-cardiac surgery were investigated. Impedance measures, Paw, Pao2 /FIo2 ratio, respiratory rate, and modified Borg scores were recorded first on low-flow oxygen and then on HFNC. Results. A strong and significant correlation existed between Paw and end-expiratory lung impedance (EELI) (r¼0.7, P,0.001). Compared with low-flow oxygen, HFNC significantly increased EELI by 25.6% [95% confidence interval (CI) 24.3, 26.9] and Paw by 3.0 cm H2O (95% CI 2.4, 3.7). Respiratory rate reduced by 3.4 bpm (95% CI 1.7, 5.2) with HFNC use, tidal impedance variation increased by 10.5% (95% CI 6.1, 18.3), and Pao2 /FIo2 ratio improved by 30.6 mm Hg (95% CI 17.9, 43.3). A trend towards HFNC improving subjective dyspnoea scoring (P¼0.023) was found. Increases in EELI were significantly influenced by BMI, with larger increases associated with higher BMIs (P,0.001). Conclusions.ThisstudysuggeststhatHFNCsreducerespiratoryrateandimproveoxygenation byincreasingbothEELVandtidalvolumeandaremostbeneficialinpatientswithhigherBMIs.
385 citations
TL;DR: Patients undergoing general, trauma, or oral and maxillofacial surgery were studied and a treatment threshold of average pain of NRS≥4 was considered to identify patients with pain of moderate-to-severe intensity.
Abstract: Background Cut-off points (CPs) of the numeric rating scale (NRS 0–10) are regularly used in postoperative pain treatment. However, there is insufficient evidence to identify the optimal CP between mild and moderate pain. Methods A total of 435 patients undergoing general, trauma, or oral and maxillofacial surgery were studied. To determine the optimal CP for pain treatment, four approaches were used: first, patients estimated their tolerable postoperative pain intensity before operation; secondly, 24 h after surgery, they indicated if they would have preferred to receive more analgesics; thirdly, satisfaction with pain treatment was analysed, and fourthly, multivariate analysis was used to calculate the optimal CP for pain intensities in relation to pain-related interference with movement, breathing, sleep, and mood. Results The estimated tolerable postoperative pain before operation was median (range) NRS 4.0 (0–10). Patients who would have liked more analgesics reported significantly higher average pain since surgery [median NRS 5.0 (0–9)] compared with those without this request [NRS 3.0 (0–8)]. Patients satisfied with pain treatment reported an average pain intensity of median NRS 3.0 (0–8) compared with less satisfied patients with NRS 5.0 (2–9). Analysis of average postoperative pain in relation to pain-related interference with mood and activity indicated pain categories of NRS 0–2, mild; 3–4, moderate; and 5–10, severe pain. Conclusions Three of the four methods identified a treatment threshold of average pain of NRS≥4. This was considered to identify patients with pain of moderate-to-severe intensity. This cut-off was indentified as the tolerable pain threshold.
360 citations
TL;DR: Perioperative pregabalin administration reduced opioid consumption and opioid-related adverse effects after surgery, and the risk of visual disturbance was greater.
Abstract: Multimodal treatment of postoperative pain using adjuncts such as gabapentin is becoming more common. Pregabalin has anti-hyperalgesic properties similar to gabapentin. In this systematic review, we evaluated randomized, controlled trials (RCTs) for the analgesic efficacy and opioid-sparing effect of pregabalin in acute postoperative pain. A systematic search of Medline (1966–2010), the Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar was performed. We identified 11 valid RCTs that used pregabalin for acute postoperative pain. Postoperative pain intensity was not reduced by pregabalin. Cumulative opioid consumption at 24 h was significantly decreased with pregabalin. At pregabalin doses of
301 citations
TL;DR: The risks of anaemia and transfusion in the light of substantial variations in transfusion practices, increasing costs, shrinking pool of donated resources, and ambiguity about actual clinical benefits of banked allogeneic blood demand better management strategies targeted at improving patient outcomes.
Abstract: Summary While complex physiological mechanisms exist to regulate and optimize tissue oxygenation under various conditions, clinical and experimental evidence indicates that anaemia, unchecked, is associated with organ injury and unfavourable outcomes. More data (especially from human studies) are needed to answer questions regarding the optimal approaches to the treatment of acute and chronic anaemia. Meantime, allogeneic blood transfusions remain the most common treatment, particularly in surgical/trauma patients and those with moderate-to-severe anaemia. Clinical studies emphasize the paradox that both anaemia and transfusion are associated with organ injury and increased morbidity and mortality across a wide span of disease states and surgical interventions. Further characterization of the mechanisms of injury is needed to appropriately balance these risks and to develop novel treatment strategies that will improve patient outcomes. Here, we present the current understanding of the physiological mechanisms of tissue oxygen delivery, utilization, adaptation, and survival in the face of anaemia and current evidence on the independent (and often, synergistic) deleterious impact of anaemia and transfusion on patient outcomes. The risks of anaemia and transfusion in the light of substantial variations in transfusion practices, increasing costs, shrinking pool of donated resources, and ambiguity about actual clinical benefits of banked allogeneic blood demand better management strategies targeted at improving patient outcomes.
294 citations
TL;DR: The combined effect of dexamethasone and either drug produced nearly the same 22 h of analgesia, with the effect being stronger with ropivacaine.
Abstract: Background Pain after shoulder surgery is often treated with interscalene nerve blocks. Single-injection blocks are effective, but time-limited. Adjuncts such as dexamethasone may help. We thus tested the hypothesis that adding dexamethasone significantly prolongs the duration of ropivacaine and bupivacaine analgesia and that the magnitude of the effect differs among the two local anaesthetics. Methods In a double-blinded trial utilizing single-injection interscalene block, patients were randomized to one of four groups: (i) ropivacaine: 0.5% ropivacaine; (ii) bupivacaine: 0.5% bupivacaine; (iii) ropivacaine and steroid: 0.5% ropivacaine mixed with dexamethasone 8 mg; and (iv) bupivacaine and steroid: 0.5% bupivacaine mixed with dexamethasone 8 mg. The primary outcome was time to first analgesic request after post-anaesthesia care unit discharge. The Kaplan–Meier survival density estimation and stratified Cox's proportional hazard regression were used to compare groups. Results Dexamethasone significantly prolonged the duration of analgesia of both ropivacaine [median (inter-quartile range) 11.8 (9.7, 13.8) vs 22.2 (18.0, 28.6) h, log-rank P Conclusions Dexamethasone prolongs analgesia from interscalene blocks using ropivacaine or bupivacaine, with the effect being stronger with ropivacaine. However, block duration was longer with plain bupivacaine than ropivacaine. Thus, although dexamethasone prolonged the action of ropivacaine more than that of bupivacaine, the combined effect of dexamethasone and either drug produced nearly the same 22 h of analgesia.
TL;DR: The risk-benefit balance of analgesia by TEA is favourable and should foster clinical use, and safe time intervals regarding the use of concomitant anticoagulants and consideration of reduced renal function impairing their elimination must be observed.
Abstract: Thoracic epidural anaesthesia (TEA) reduces cardiac and splanchnic sympathetic activity and thereby influences perioperative function of vital organ systems. A recent meta-analysis suggested that TEA decreased postoperative cardiac morbidity and mortality. TEA appears to ameliorate gut injury in major surgery as long as the systemic haemodynamic effects of TEA are adequately controlled. The functional benefit in fast-track and laparoscopic surgery needs to be clarified. Better pain control with TEA is established in a wide range of surgical procedures. In a setting of advanced surgical techniques, fast-track regimens and a low overall event rate, the number needed to treat to prevent one death by TEA is high. The risk of harm by TEA is even lower, and other methods used to control perioperative pain and stress response also carry specific risks. To optimize the risk-benefit balance of TEA, safe time intervals regarding the use of concomitant anticoagulants and consideration of reduced renal function impairing their elimination must be observed. Infection is a rare complication and is associated with better prognosis. Close monitoring and a predefined algorithm for the diagnosis and treatment of spinal compression or infection are crucial to ensure patient safety with TEA. The risk-benefit balance of analgesia by TEA is favourable and should foster clinical use.
TL;DR: A multimodal approach to PONV should not be limited to drug therapy alone but should involve a holistic approach starting before operation and continuing intraoperatively with risk reduction strategies to which are added prophylactic antiemetics according to the assessed patient risk.
Abstract: Summary Postoperative nausea and vomiting (PONV) and pain are two of the major concerns for patients presenting for surgery. The causes of PONV are multifactorial and can largely be categorized as patient risk factors, anaesthetic technique, and surgical procedure. Antiemetics work on several different receptor sites to prevent or treat PONV. This is probably why numerous studies have now demonstrated that using more than one antiemetic is usually more effective and results in fewer side-effects than simply increasing the dose of a single antiemetic. A multimodal approach to PONV should not be limited to drug therapy alone but should involve a holistic approach starting before operation and continuing intraoperatively with risk reduction strategies to which are added prophylactic antiemetics according to the assessed patient risk for PONV. With the increasing understanding of the pathophysiology of acute pain, especially the occurrence of peripheral and central hypersensitization, it is unlikely that a single drug or intervention is sufficiently broad in its action to be adequately effective, especially with moderate or greater pain. Although morphine and its congeners are usually the foundation of pain management regimens, as their dose increases so does the incidence of side-effects. Thus, the approach for the management of acute postoperative pain is to use multiple drugs or modalities (e.g. regional anaesthesia) to maximize pain relief and reduce side-effects.
TL;DR: MP 125 mg before surgery improves analgesia and immediate recovery after TKA, even when combined with a multimodal analgesic regime, and these findings call for further studies on safety aspects.
Abstract: Background. Total knee arthroplasty (TKA) is associated with severe pain and inflammation despite an extensive multimodal analgesic approach, but the effect of high-dose glucocorticoid administration has not been studied. Methods. Forty-eight patients undergoing unilateral TKA were included in a randomized, double-blind, placebo-controlled trial receiving preoperative methylprednisolone (MP) 125 mg i.v. or saline. All surgery was performed under lumbar spinal anaesthesia and patients received a standardized, multimodal analgesic regime. The primary endpoint was pain during walking 24 h after surgery, and secondary endpoints were pain at rest, pain upon hip flexion, and pain upon knee flexion. Pain assessments were performed repeatedly for the first 48 h after surgery, in a questionnaire from days 2 to 10, and at follow-up on days 21 and 30. Tertiary endpoints were postoperative nausea and vomiting (PONV), plasma Creactive protein (CRP) concentrations, fatigue, sleep quality, and rescue analgesic and antiemetic requirements. Results. Pain during walking was significantly lower in the MP group up to 32 h after operation. Overall pain and cumulative pain scores (2–48 h) were lower for all pain assessments (P,0.04). Consumption of rescue oxycodone was lower from 0 to 24 h (P¼0.02) and PONV, consumption of ondansetron reduced (P,0.05), and CRP concentrations were lower at 24 h (P,0.000001). Fatigue throughout the day of surgery was lower (P¼0.02), but sleep quality was worse on the first night (P¼0.002). No side-effects or complications were observed in other respects. Conclusions. MP 125 mg before surgery improves analgesia and immediate recovery after TKA, even when combined with a multimodal analgesic regime. These findings call for further studies on safety aspects. Registered with ClinicalTrails.gov under the US National Library of Medicine (registration number: NCT00968578).
TL;DR: In penetrating trauma, HES provided significantly better lactate clearance and less renal injury than saline, and no firm conclusions could be drawn for blunt trauma.
Abstract: Background The role of fluids in trauma resuscitation is controversial. We compared resuscitation with 0.9% saline vs hydroxyethyl starch, HES 130/0.4, in severe trauma with respect to resuscitation, fluid volume, gastrointestinal recovery, renal function, and blood product requirements. Methods Randomized, controlled, double-blind study of severely injured patients requiring>3 litres of fluid resuscitation. Blunt and penetrating trauma were randomized separately. Patients were followed up for 30 days. Results A total of 115 patients were randomized; of which, 109 were studied. For patients with penetrating trauma ( n =67), the mean ( sd ) fluid requirements were 5.1 (2.7) litres in the HES group and 7.4 (4.3) litres in the saline group ( P n =42), there was no difference in study fluid requirements, but the HES group required significantly more blood products [packed red blood cell volumes 2943 (1628) vs 1473 (1071) ml, P =0.005] and was more severely injured than the saline group (median injury severity score 29.5 vs 18; P =0.01). Haemodynamic data were similar, but, in the penetrating group, plasma lactate concentrations were lower over the first 4 h ( P =0.029) and on day 1 with HES than with saline [2.1 (1.4) vs 3.2 (2.2) mmol litre −1 ; P =0.017]. There was no difference between any groups in time to recovery of bowel function or mortality. In penetrating trauma, renal injury occurred more frequently in the saline group than the HES group (16% vs 0%; P =0.018). In penetrating trauma, maximum sequential organ function scores were lower with HES than with saline (median 2.4 vs 4.5, P =0.012). No differences were seen in safety measures in the blunt trauma patients. Conclusions In penetrating trauma, HES provided significantly better lactate clearance and less renal injury than saline. No firm conclusions could be drawn for blunt trauma. Study registration: ISRCTN 42061860.
TL;DR: The data enlarge the body of evidence showing that ROTEM(®) assays are useful in trauma patients and treatment concepts should focus on maintaining fibrin polymerization and treating hyperfibrinolysis.
Abstract: Background ROTEM®/TEG® (rotational thromboelastometry) assays appear to be useful for the treatment of bleeding trauma patients. However, data on the prevalence and impact of abnormal ROTEM® assays are scarce. Methods This is a prospective cohort study of blunt trauma patients (Injury Severity Score ≥15 or Glasgow Coma Score ≤14) admitted to Innsbruck Medical University Hospital between July 2005 and July 2008. Standard coagulation tests, antithrombin (AT), prothrombin fragments (F1+2), thrombin–antithrombin complex (TAT), and ROTEM® assays were measured after admission. Data on 334 patients remained for final analysis. Results ROTEM® parameters correlated with standard coagulation tests (all Spearman r>0.5), and significant differences in mortality were detected for defined ROTEM® thresholds [FIBTEM 7 mm (21% vs 9%, P=0.006), EXTEM MCF (maximum clot firmness) 45 mm (25.4% vs 9.4%, P=0.001)]. EXTEM MCF was independently associated with early mortality [odds ratio (OR) 0.94, 95% confidence interval (CI) 0.9–0.99] and MCF FIBTEM with need for red blood cell transfusion (OR 0.92, 95% CI 0.87–0.98). In polytrauma patients with or without head injury (n=274), the prevalence of low fibrinogen concentrations, impaired fibrin polymerization, and reduced clot firmness was 26%, 30%, and 22%, respectively, and thus higher than the prolonged international normalized ratio (14%). Hyperfibrinolysis increased fatality rates and occurred as frequently in isolated brain injury (n=60) as in polytrauma (n=274) (5%, 95% CI 1.04–13.92 vs 7.3%, 95% CI 4.52–11.05). All patients showed elevated F1+2 and TAT and low AT levels, indicating increased thrombin formation. Conclusions Our data enlarge the body of evidence showing that ROTEM® assays are useful in trauma patients. Treatment concepts should focus on maintaining fibrin polymerization and treating hyperfibrinolysis.
TL;DR: Given the general considerations of avoiding fetal exposure to unnecessary medication and potential protection of the maternal airway, regional anaesthesia is usually preferred in pregnancy when it is practical for the medical and surgical condition.
Abstract: Surgery during pregnancy is complicated by the need to balance the requirements of two patients. Under usual circumstances, surgery is only conducted during pregnancy when it is absolutely necessary for the wellbeing of the mother, fetus, or both. Even so, the outcome is generally favourable for both the mother and the fetus. All general anaesthetic drugs cross the placenta and there is no optimal general anaesthetic technique. Neither is there convincing evidence that any particular anaesthetic drug is toxic in humans. There is weak evidence that nitrous oxide should be avoided in early pregnancy due to a potential association with pregnancy loss with high exposure. There is evidence in animal models that many general anaesthetic techniques cause inappropriate neuronal apoptosis and behavioural deficits in later life. It is not known whether these considerations affect the human fetus but studies are underway. Given the general considerations of avoiding fetal exposure to unnecessary medication and potential protection of the maternal airway, regional anaesthesia is usually preferred in pregnancy when it is practical for the medical and surgical condition. When surgery is indicated during pregnancy maintenance of maternal oxygenation, perfusion and homeostasis with the least extensive anaesthetic that is practical will assure the best outcome for the fetus.
TL;DR: The Nottingham Hip Fracture Score can be used to stratify the risk of 1 yr mortality after hip fracture surgery and was investigated whether the NHFS was a predictor of 1 year mortality in patients undergoing surgical repair of fractured neck of femur.
Abstract: Background Surgical repair of hip fractures is associated with high postoperative mortality. The identification of high-risk patients might be of value in aiding clinical management decisions and resource allocation. The Nottingham Hip Fracture Score (NHFS) is a scoring system validated for the prediction of 30 day mortality after hip fracture surgery. It is made up of seven independent predictors of mortality that have been incorporated into a risk score: age (66–85 and ≥86 yr); sex (male); number of co-morbidities (≥2), admission mini-mental test score (≤6 out of 10), admission haemoglobin concentration (≤10 g dl−1), living in an institution; and the presence of malignancy. We investigated whether the NHFS was a predictor of 1 yr mortality in patients undergoing surgical repair of fractured neck of femur. Methods NHFS was retrospectively calculated for 6202 patients who had undergone hip fracture surgery between 1999 and 2009. One year and 30 day postoperative mortality data were collected both from hospital statistics and the Office of National Statistics. Results Overall mortality was 8.3% at 30 days and 29.3% at 1 yr. An NHFS of ≤4 was considered low risk and a score of ≥5 high risk. Survival was greater in the low-risk group at 30 days [96.5% vs 86.3% (P Conclusions NHFS can be used to stratify the risk of 1 yr mortality after hip fracture surgery.
TL;DR: Ultrasound-guided TAP block provided better pain control than 'blind' IHN block after inguinal hernia repair but did not prevent the occurrence of chronic pain.
Abstract: Background Transversus abdominis plane (TAP) block has been reported to provide effective analgesia after lower abdominal surgery, but there are few data comparing ilioinguinal/iliohypogastric nerve (IHN) block with ultrasound-guided TAP block in patients undergoing inguinal hernia repair. Methods Two hundred and seventy-three patients undergoing day-case open inguinal hernia repair with a mesh were randomly allocated to receive either ultrasound-guided TAP block or blind IHN block with levobupivacaine 0.5%, before surgery. Patients were monitored for visual analogue scale (VAS) scores at rest (in the post-anaesthesia care unit, and at 4 and 12 h) and at rest and during movement (at 24, 48 h, 3 and 6 months). Pain at 6 months was also assessed using the DN4 questionnaire for neuropathic pain. Results Median VAS pain scores at rest were lower in the ultrasound-guided TAP group at 4 h (11 vs 15, P=0.04), at 12 h (20 vs 30, P=0.0014), and at 24 h (29 vs 33, P=0.013). Pain after the first 24 h, at 3 and 6 months after surgery, and DN4 scores were similar in both groups (P=NS). The proportion of patients with VAS >40 mm on movement at 6 months was comparable {18.2% [95% CI (12.2–26.1%)] vs 22.4% (15.8–30.6%) in the TAP and IHN groups, respectively, P=0.8}. Postoperative morphine requirements were lower during the first 24 h in the TAP block group (P=0.03). Conclusions Ultrasound-guided TAP block provided better pain control than ‘blind' IHN block after inguinal hernia repair but did not prevent the occurrence of chronic pain.
TL;DR: Evidence that the triggering of MH by drugs is dose-dependent but the minimum dose that will trigger the condition is unknown is discussed, which has implications for the preparation of anaesthetic machines when used for known or suspected MH patients.
Abstract: Over the past 50 yr, many drugs have been implicated as triggers of malignant hyperthermia (MH), a potentially fatal pharmacogenetic disorder of skeletal muscle calcium regulation. This review discusses the potent inhalation agents as the principal triggers and evidence that the modern agents, desflurane, sevoflurane, and isoflurane, can cause florid MH reactions in the same way as halothane but also are associated with reactions whose onset is delayed for several hours into anaesthesia. There is evidence that the triggering of MH by drugs is dose-dependent but the minimum dose that will trigger the condition is unknown. This has implications for the preparation of anaesthetic machines when used for known or suspected MH patients. While succinylcholine enhances the response of potent inhalation anaesthetics, its role as an inherent trigger of the condition is controversial. Non-depolarizing neuromuscular blocking drugs appear to protect against the development of MH and this may be by blocking excitation-coupled calcium entry—a recently described route of skeletal muscle calcium entry that may also explain the mechanism of the effect of succinylcholine in MH. Another mechanism for extracellular calcium influx, store-operated calcium entry, is activated in MH muscle and may explain how a triggered reaction is sustained. Finally, reports of drugs that have been implicated as additional triggers of MH over the past 10 yr are discussed.
TL;DR: A sevoflurane-based anaesthesia was associated with better short-term postoperative cognitive performance than propofol, and patients with impaired cognitive performance before operation may be at particular risk for intraoperative cerebral insult.
Abstract: Background Cognitive dysfunction is a frequent complication after cardiac surgery and has been found to be associated with decreases in cerebral oxygen saturation S c O 2 measured with near-infrared spectroscopy. Sevoflurane has neuroprotective properties in vitro and in animal models. This study was designed to determine cognitive and clinical outcomes after sevoflurane- compared with propofol-based anaesthesia for on-pump cardiac surgery and the impact of decreases in S c O 2 under different anaesthesia regimens. Methods One hundred and twenty-eight patients were randomly assigned to either i.v. anaesthesia with propofol- (PROP) or sevoflurane-based anaesthesia (SEVO). An intraoperative S c O 2 Results The analysis groups had differences in baseline cognitive performance. Analysis of variance for repeated measures (incorporating covariance of baseline scores) showed that in three of four cognitive tests, patients with cerebral desaturation showed worse results than patients without desaturation. Patients assigned to sevoflurane-based anaesthesia showed better results in all cognitive tests than patients after propofol. Interactions between the anaesthetic regimen and desaturation were found in all four cognitive tests. There were no differences in markers of organ dysfunction or general clinical outcome. Conclusions Patients with impaired cognitive performance before operation may be at particular risk for intraoperative cerebral insult. A sevoflurane-based anaesthesia was associated with better short-term postoperative cognitive performance than propofol.
TL;DR: Associated with changes in CO, decreased after phenylephrine treatment, but remained unchanged after ephedrine treatment, implies a cause-effect relationship between global and regional haemodynamics.
Abstract: † Phenylephrine, but not ephedrine, decreased cardiac output (CO) and brain oxygenation. † This study highlights the importance of CO in preserving brain oxygenation during management of intraoperative hypotension. Background. How phenylephrine and ephedrine treatments affect global and regional haemodynamics is of major clinical relevance. Cerebral tissue oxygen saturation (SctO2 )-guided management may improve postoperative outcome. The physiological variables responsible for SctO2 changes induced by phenylephrine and ephedrine bolus treatment in anaesthetized patients need to be defined. Methods. A randomized two-treatment cross-over trial was conducted: one bolus dose of phenylephrine (100‐200 mg) and one bolus dose of ephedrine (5‐20 mg) were given to 29 ASA I‐III patients anaesthetized with propofol and remifentanil. SctO2, mean arterial pressure (MAP), cardiac output (CO), and other physiological variables were recorded before and after treatments. The associations of changes were analysed using linear-mixed models. Results. The COdecreased significantlyafter phenylephrine treatment [△CO¼ 22.1 (1.4) litre min 21 , P,0.001], but was preserved after ephedrine treatment [△CO¼0.5 (1.4) litre min 21 , P.0.05]. The SctO2 was significantly decreased after phenylephrine treatment [△SctO2 ¼ 23.2 (3.0)%, P,0.01] but preserved after ephedrine treatment [△SctO2 ¼0.04 (1.9)%, P.0.05]. CO was identified to have the most significant association with SctO2 (P,0.001). After taking CO into consideration, the other physiological variables, including MAP, were not significantly associated with SctO2 (P.0.05). Conclusions. Associated with changes in CO, SctO2 decreased after phenylephrine treatment, but remained unchanged after ephedrine treatment. The significant correlation between CO and SctO2 implies a cause‐effect relationship between global and regional haemodynamics.
TL;DR: Both formulations are associated with few AEs, although patients receiving propacetamol have a higher incidence of pain on infusion, and a single dose of either prop acetamol or i.v. paracetaml provides around 4 h of effective analgesia for about 37% of patients with acute postoperative pain.
Abstract: Summary. Paracetamol is the most commonly prescribed analgesic for the treatment of acute pain. The efficacy and safety of i.v. formulations of paracetamol is unclear. We performed a systematic search (multiple databases, bibliographies, any language, to May 2010) for single-dose, randomized, controlled clinical trials of propacetamol or i.v. paracetamol for acute postoperative pain in adults or children. Thirty-six studies involving 3896 patients were included. For the primary outcome, 37% of patients (240/367) receiving propacetamol or i.v. paracetamol experienced at least 50% pain relief over 4 h compared with 16% (68/527) receiving placebo (number needed to treat¼4.0; 95% confidence interval, 3.5–4.8). The proportion of patients in propacetamol or i.v. paracetamol groups experiencing at least 50% pain relief diminished over 6 h. Patients receiving propacetamol or paracetamol required 30% less opioid over 4 h and 16% less opioid over 6 h than those receiving placebo. However, this did not translate to a reduction in opioid-induced adverse events (AEs). Similar comparisons between propacetamol or i.v. paracetamol and active comparators were either not statistically significant, not clinically significant, or both. AEs occurred at similar rates with propacetamol or i.v. paracetamol and placebo. However, pain on infusion occurred more frequently in those receiving propacetamol compared with placebo (23% vs 1%). A single dose of either propacetamol or i.v. paracetamol provides around 4 h of effective analgesia for about 37% of patients with acute postoperative pain. Both formulations are associated with few AEs, although patients receiving propacetamol have a higher incidence of pain on infusion.
TL;DR: Regional anaesthesia offers superior analgesia over opioid-based analgesia, and a significant reduction in postoperative pain is still a worthwhile outcome.
Abstract: In recent decades, a number of studies have attempted to determine whether regional anaesthesia offers convincing benefits over general anaesthesia. However, today we interpret meta-analyses more carefully, and it remains unclear whether regional anaesthesia reduces mortality. However, regional anaesthesia offers superior analgesia over opioid-based analgesia, and a significant reduction in postoperative pain is still a worthwhile outcome. Recent developments in technical aspects of regional anaesthesia have the potential to provide significant advantages for many patients in all age groups. Moreover, studies focusing on specific outcomes have shown benefits for regional anaesthesia used for surgery and postoperative analgesia.
TL;DR: In these at-risk patients undergoing elective non-cardiac surgery, there did not find any difference in terms of occurrence of major thrombotic or bleeding events between preoperative maintenance or interruption of aspirin.
Abstract: Background Patients receiving anti-platelet agents for secondary cardiovascular prevention frequently require non-cardiac surgery. A substantial proportion of these patients have their anti-platelet drug discontinued before operation; however, there is uncertainty about the impact of this practice. The aim of this study was to compare the effect of maintenance or interruption of aspirin before surgery, in terms of major thrombotic and bleeding events. Methods Patients treated with anti-platelet agents for secondary prevention and undergoing intermediate- or high-risk non-cardiac surgery were included in this multicentre, randomized, placebo-controlled, trial. We substituted non-aspirin anti-platelets with aspirin (75 mg daily) or placebo starting 10 days before surgery. The primary outcome was a composite score evaluating both major thrombotic and bleeding adverse events occurring within the first 30 postoperative days weighted by their severity (weights were established a priori using a Delphi consensus process). Analyses followed the intention-to-treat principle. Results We randomized 291 patients (n=145, aspirin group, and n=146, placebo group). The most frequent surgical procedures were orthopaedic surgery (52.2%), abdominal surgery (20.6%), and urologic surgery (15.5%). No significant difference was observed neither in the primary outcome score [mean values (sd)=0.67 (2.05) in the aspirin group vs 0.65 (2.04) in the placebo group, P=0.94] nor at day 30 in the number of major complications between groups. Conclusions In these at-risk patients undergoing elective non-cardiac surgery, we did not find any difference in terms of occurrence of major thrombotic or bleeding events between preoperative maintenance or interruption of aspirin. ClinicalTrials.gov identifier. NCT00190307.
TL;DR: Bilateral PVB has been used successfully in the thoracic, abdominal, and pelvic regions, sometimes obviating the need for general anaesthesia, and there are no reports of systemic toxicity.
Abstract: Summary Paravertebral nerve blocks (PVBs) can provide excellent intraoperative anaesthetic and postoperative analgesic conditions with less adverse effects and fewer contraindications than central neural blocks. Most published data are related to unilateral PVB, but its potential as a bilateral technique has been demonstrated. Bilateral PVB has been used successfully in the thoracic, abdominal, and pelvic regions, sometimes obviating the need for general anaesthesia. We have reviewed the use of bilateral PVB in association with surgery and chronic pain therapy. This covers 12 published studies with a total of 538 patients, and with varied methods and outcome measures. Despite the need for relatively large doses of local anaesthetics, there are no reports of systemic toxicity. The incidence of complications such as pneumothorax and hypotension is low. More studies on the use of bilateral PVB are required.
TL;DR: After a single simulation training session, improvements in cricothyroidotomy skills are retained for at least 1 yr, suggesting that high-fidelity simulation training, along with practice and feedback, can be used to maintain complex procedural skills for at minimum 1 yr.
Abstract: Background Simulation has been shown to be effective in teaching complex emergency procedural skills. However, the retention of these skills for a period of up to 1 yr has not been studied. We aimed to investigate the 6 month and 1 yr retention of the complex procedural skill of cricothyroidotomy in attending anaesthetists using a high-fidelity-simulated cannot intubate, cannot ventilate (CICV) scenario. Methods Thirty-eight attending anaesthetists participated individually in a high-fidelity-simulated CICV scenario (pretest) that required a cricothyroidotomy for definitive airway management. Immediately after a debriefing and structured teaching session on cricothyroidotomy insertion, subjects managed a second identical CICV scenario (post-test). Each anaesthetist was randomized to either a ‘6 month retention' or a ‘12 month retention' group. No further teaching occurred. At their respective retention times, each anaesthetist managed a third identical CICV scenario (retention post-test). Two blinded experts independently rated videos of all performances in a random order, using a specific checklist (CL) score, a global-rating scale (GRS) score, and procedural time (PT). Results Subjects from both groups improved on their cricothyroidotomy skill performances from pretest to immediate post-test and from pretest to retention post-test, irrespective of the retention interval; CL mean (sd) 8.00 (2.39) vs 8.88 (1.53), P =0.49; GRS 28.00 (7.80) vs 31.25 (5.31), P =0.25; PT 102.83 (63.81) s vs 106.88 (36.68) s, P =0.73. Conclusions After a single simulation training session, improvements in cricothyroidotomy skills are retained for at least 1 yr. These findings suggest that high-fidelity simulation training, along with practice and feedback, can be used to maintain complex procedural skills for at least 1 yr.
TL;DR: It is unlikely that definitive clinical studies absolving general anaesthetics of neurotoxicity will become available in the near future, requiring clinicians to use careful judgement when using these profound neurodepressants in vulnerable patients.
Abstract: It has been assumed that anaesthetics have minimal or no persistent effects after emergence from anaesthesia. However, general anaesthetics act on multiple ion channels, receptors, and cell signalling systems in the central nervous system to produce anaesthesia, so it should come as no surprise that they also have non-anaesthetic actions that range from beneficial to detrimental. Accumulating evidence is forcing the anaesthesia community to question the safety of general anaesthesia at the extremes of age. Preclinical data suggest that inhaled anaesthetics can have profound and long-lasting effects during key neurodevelopmental periods in neonatal animals by increasing neuronal cell death (apoptosis) and reducing neurogenesis. Clinical data remain conflicting on the significance of these laboratory data to the paediatric population. At the opposite extreme in age, elderly patients are recognized to be at an increased risk of postoperative cognitive dysfunction (POCD) with a well-recognized decline in cognitive function after surgery. The underlying mechanisms and the contribution of anaesthesia in particular to POCD remain unclear. Laboratory models suggest anaesthetic interactions with neurodegenerative mechanisms, such as those linked to the onset and progression of Alzheimer's disease, but their clinical relevance remains inconclusive. Prospective randomized clinical trials are underway to address the clinical significance of these findings, but there are major challenges in designing, executing, and interpreting such trials. It is unlikely that definitive clinical studies absolving general anaesthetics of neurotoxicity will become available in the near future, requiring clinicians to use careful judgement when using these profound neurodepressants in vulnerable patients.
TL;DR: It is concluded that the prognostic value of the modified Mallampati score was worse than that estimated by previous meta-analyses and may well be a part of a multivariate model for the prediction of a difficult tracheal intubation.
Abstract: The modified Mallampati score is used to predict difficult tracheal intubation. We have conducted a meta-analysis of published studies to evaluate the Mallampati score as a prognostic test. A total of 55 studies involving 177 088 patients were included after comprehensive electronic and manual searches. The pooled estimates from the meta-analyses were calculated based on a random-effects model and a summary receiver operating curve. Meta-regression analyses were performed to explore sources of possible heterogeneity between the studies. The summary receiver operating curve demonstrated an area under the curve of 0.75. The pooled odds ratio for a difficult intubation with a modified Mallampati score of III or IV was 5.89 [95% confidence interval (CI), 4.74-7.32]. The pooled estimates of the specificity and sensitivity were 0.91 (CI, 0.91-0.91) and 0.35 (CI, 0.34-0.36), respectively. The pooled positive and negative likelihood ratios were 4.13 (CI, 3.60-4.66) and 0.70 (CI, 0.65-0.75), respectively. The meta-analyses had statistical and clinical heterogeneity ranging from 87.2% to 99.4%. Meta-regression analyses did not identify any significant explanation of the heterogeneity. We conclude that the prognostic value of the modified Mallampati score was worse than that estimated by previous meta-analyses. Our assessment shows that the modified Mallampati score is inadequate as a stand-alone test of a difficult laryngoscopy or tracheal intubation, but it may well be a part of a multivariate model for the prediction of a difficult tracheal intubation.
TL;DR: The risk score based on seven objective and easily assessed factors can accurately predict MACCE occurrence after non-cardiac surgery in a population at intermediate-to-high surgery-specific risk.
Abstract: Background Major adverse cardiac and cerebrovascular events (MACCE) represent the most common cause of serious perioperative morbidity and mortality. Our aim was to identify risk factors for MACCE in a broad surgical population with intermediate-to-high surgery-specific risk and to build and validate a model to predict the risk of MACCE. Methods A prospective, multicentre study of patients undergoing surgical procedures under general or regional anaesthesia in 23 hospitals. The main outcome was the occurrence of at least one perioperative MACCE, defined as any of the following complications from admittance to discharge: cardiac death, cerebrovascular death, non-fatal cardiac arrest, acute myocardial infarction, congestive heart failure, new cardiac arrhythmia, angina, or stroke. The MACCE predictive index was based on β-coefficients and validated in an external data set. Results Of 3387 patients recruited, 146 (4.3%) developed at least one MACCE. The regression model identified seven independent risk factors for MACCE: history of coronary artery disease, history of chronic congestive heart failure, chronic kidney disease, history of cerebrovascular disease, preoperative abnormal ECG, intraoperative hypotension, and blood transfusion. The area under the receiver-operating characteristic curve was 75.9% (95% confidence interval, 71.2–80.6%). Conclusions The risk score based on seven objective and easily assessed factors can accurately predict MACCE occurrence after non-cardiac surgery in a population at intermediate-to-high surgery-specific risk.