Showing papers in "Acta Anaesthesiologica Scandinavica in 2009"

Teamwork and patient safety in dynamic domains of healthcare: a review of the literature.

Abstract: Aims/background This review examines current research on teamwork in highly dynamic domains of healthcare such as operating rooms, intensive care, emergency medicine, or trauma and resuscitation teams with a focus on aspects relevant to the quality and safety of patient care Results Evidence from three main areas of research supports the relationship between teamwork and patient safety: (1) Studies investigating the factors contributing to critical incidents and adverse events have shown that teamwork plays an important role in the causation and prevention of adverse events (2) Research focusing on healthcare providers' perceptions of teamwork demonstrated that (a) staff's perceptions of teamwork and attitudes toward safety-relevant team behavior were related to the quality and safety of patient care and (b) perceptions of teamwork and leadership style are associated with staff well-being, which may impact clinician' ability to provide safe patient care (3) Observational studies on teamwork behaviors related to high clinical performance have identified patterns of communication, coordination, and leadership that support effective teamwork Conclusion In recent years, research using diverse methodological approaches has led to significant progress in team research in healthcare The challenge for future research is to further develop and validate instruments for team performance assessment and to develop sound theoretical models of team performance in dynamic medical domains integrating evidence from all three areas of team research identified in this review This will help to improve team training efforts and aid the design of clinical work systems supporting effective teamwork and safe patient care

Outcome, timing and adverse events in therapeutic hypothermia after out-of-hospital cardiac arrest

Abstract: Background: Therapeutic hypothermia (TH) after cardiac arrest protects from neurological sequels and death and is recommended in guidelines. The Hypothermia Registry was founded to the monitor outcome, performance and complications of TH. Methods: Data on out-of-hospital cardiac arrest (OHCA) patients admitted to intensive care for TH were registered. Hospital survival and long-term outcome (6-12 months) were documented using the Cerebral Performance Category (CPC) scale, CPC 1-2 representing a good outcome and 3-5 a bad outcome. Results: From October 2004 to October 2008, 986 TH-treated OHCA patients of all causes were included in the registry. Long-term outcome was reported in 975 patients. The median time from arrest to initiation of TH was 90 min (interquartile range, 60-165 min) and time to achieving the target temperature ( 90% having a good neurological function at long-term follow-up. Factors related to the timing of TH had no apparent association to outcome. The incidence of adverse events was acceptable but the risk of bleeding was increased if angiography/PCI was performed.

‘Liberal’ vs. ‘restrictive’ perioperative fluid therapy – a critical assessment of the evidence

Abstract: Background: Several studies have assessed the effect of a ‘liberal’ vs. a ‘restrictive’ perioperative fluid regimen on post-operative outcome. The literature was reviewed in order to provide recommendations regarding perioperative fluid regimens. Methods: A PubMed search identified randomized clinical trials and cited studies, comparing two different fixed fluid volumes on post-operative clinical outcome in major surgery. Studies were assessed for the type of surgery, primary and secondary outcome endpoints, the type and volume of administered fluid and the definition of the perioperative period. Also, information regarding perioperative care and type of anaesthesia was assessed. Results: In the seven randomized studies identified, the range of the liberal intraoperative fluid regimen was from 2750 to 5388 ml compared with 998 to 2740 ml for the restrictive fluid regimen. The period for fluid therapy and outcome endpoints were inconsistently defined and only two studies reported perioperative care principles and discharge criteria. Three studies found an improved outcome (morbidity/hospital stay) with a restrictive fluid regimen whereas two studies found no difference and two studies found differences in the selected outcome parameters. Conclusion: Liberal vs. restrictive fixed-volume regimens are not well defined in the literature regarding the definition, methodology and results, and lack the use of or information on evidence-based standardized perioperative care-principles (fast-track surgery), thereby precluding evidence-based guidelines for procedure-specific perioperative fixed-volume regimens. Optimization of perioperative fluid management may include a combination of fixed crystalloid administration to replace extra-vascular losses and avoiding fluid excess, together with individualized goal-directed colloid administration to maintain a maximal stroke volume.

Dexmedetomidine provides cortical neuroprotection: impact on anaesthetic-induced neuroapoptosis in the rat developing brain.

Abstract: Background: Recent evidence has demonstrated the anti-apoptotic of dexmedetomidine in different brain injury models. Herein, we investigated whether dexmedetomidine could directly protect against cortical injury in vitro and in vivo. Methods: Apoptosis was induced by staurosporine or wortmannin treatment in cortical neuronal cultures in vitro or by 6 h of isoflurane (0.75%) administration to post-natal day 7 rat pups in vivo. Dexmedetomidine was then applied in escalating doses to assess the neuroprotective potential of this agent. Cell survival was quantified using an MTT assay in vitro and in vivo apoptosis was assessed using cleaved caspase-3 immunohistochemistry. Cortical Western blots were conducted for the cellular survival proteins Bcl-2 and phosphorylated extracellular signal-regulated protein kinase (pERK)1 and 2. Results: In vitro dexmedetomidine dose-dependently prevented both staurosporine- and wortmannin-induced injury in cortical neuronal cultures, indicating that dexmedetomidine can prevent apoptosis when applied directly. In vivo isoflurane induced cortical neuroapoptosis compared with air (327±80 vs. 34±9 caspase-3-positive neurons; P<0.05). Dexmedetomidine inhibited isoflurane-induced caspase-3 expression (P<0.05), although the protection achieved did not completely attenuate the isoflurane injury (P<0.05 vs. air). Isoflurane treatment decreased Bcl-2 and pERK protein expression relative to air, an effect reversed by dexmedetomidine treatment. Conclusions: Dexmedetomidine prevents cortical apoptosis in vitro and in vivo. However, using higher doses of dexmedetomidine does not further increase protection against isoflurane injury in the cortex than previously observed.

Effect of dexmedetomidine on the characteristics of bupivacaine in a caudal block in pediatrics

Abstract: Background: Dexmedetomidine (DEX) is a highly selective α2-adrenoceptor agonist that has been used increasingly in children However, the effect of caudal DEX has not been evaluated before in children This prospective randomized double-blinded study was designed to evaluate the analgesic efficacy of caudal DEX with bupivacaine in providing pain relief over a 24-h period Methods: Sixty children (ASA status I) aged 1–6 years undergoing unilateral inguinal hernia repair/orchidopexy were allocated randomly to two groups (n=30 each) Group B received a caudal injection of bupivacaine 25 mg/ml, 1 ml/kg; Group BD received the same dose of bupivacaine mixed with DEX 1 μg/kg during sevoflurane anesthesia Processed electroencephalogram (bispectral index score), heart rate, blood pressure, pulse oximetry and end-tidal sevoflurane were recorded every 5 min The characteristics of emergence, objective pain score, sedation score and quality of sleep were recorded post-operatively Duration of analgesia and requirement for additional analgesics were noted Results: The end-tidal sevoflurane concentration and the incidence of agitation were significantly lower in the BD group (P<005) The duration of analgesia was significantly longer (P<0001) and the total consumption of rescue analgesic was significantly lower in Group BD compared with Group B (P<001) There was no statistically significant difference in hemodynamics between both groups However, group BD had better quality of sleep and a prolonged duration of sedation (P<005) Conclusion: Caudal DEX seems to be a promising adjunct to provide excellent analgesia without side effects over a 24-h period It has the advantage of keeping the patients calm for a prolonged time Implications statement: Caudally administered DEX (1 μg/kg), combined with bupivacaine, was associated with an extended duration of post-operative pain relief

Systemic inflammation in the brain-dead organ donor.

Abstract: Brain death itself impairs organ function in the potential donor, thereby limiting the number of suitable organs for transplantation. In addition, graft survival of kidneys obtained from brain-dead (BD) donors is inferior to that of kidneys obtained from living donors. Experimental studies confirm an inferior graft survival for the heart, liver and lungs from BD compared with living donors. The mechanism underlying the deteriorating effect of brain death on the organs has not yet been fully established. We know that brain death triggers massive circulatory, hormonal and metabolic changes. Moreover, the past 10 years have produced evidence that brain death is associated with a systemic inflammatory response. However, it remains uncertain whether the inflammation is induced by brain death itself or by events before and after becoming BD. The purpose of this study is to discuss the risk factors associated with brain death in general and the inflammatory response in the organs in particular. Special attention will be paid to the heart, lung, liver and kidney and evidence will be presented from clinical and experimental studies.

Gastrointestinal symptoms in intensive care patients

Abstract: Background: Gastrointestinal (GI) problems are not uniformly assessed in intensive care unit (ICU) patients and respective data in available literature are insufficient. We aimed to describe the prevalence, risk factors and importance of different GI symptoms. Methods: We prospectively studied all patients hospitalized to the General ICU of Tartu University Hospital in 2004–2007. Results: Of 1374 patients, 62 were excluded due to missing data. Seven hundred and seventy-five (59.1%) patients had at least one GI symptom at least during 1 day of their stay, while 475 (36.2%) suffered from more than one symptom. Absent or abnormal bowel sounds were documented in 542 patients (41.3%), vomiting/regurgitation in 501 (38.2%), high gastric aspirate volume in 298 (22.7%), diarrhoea in 184 (14.0%), bowel distension in 139 (10.6%) and GI bleeding in 97 (7.4%) patients during their ICU stay. Absent or abnormal bowel sounds and GI bleeding were associated with significantly higher mortality. The number of simultaneous GI symptoms was an independent risk factor for ICU mortality. The ICU length of stay and mortality of patients who had two or more GI symptoms simultaneously were significantly higher than in patients with a maximum of one GI symptom. Conclusion: GI symptoms occur frequently in ICU patients. Absence of bowel sounds and GI bleeding are associated with impaired outcome. Prevalence of GI symptoms at the first day in ICU predicts the mortality of the patients.

Ketamine attenuates post-operative cognitive dysfunction after cardiac surgery.

Abstract: Background: Post-operative cognitive dysfunction (POCD) commonly occurs after cardiac surgery. Ketamine exerts neuroprotective effects after cerebral ischemia by anti-excitotoxic and anti-inflammatory mechanisms. We hypothesized that ketamine attenuates POCD in patients undergoing cardiac surgery concomitant with an anti-inflammatory effect. Methods: Patients randomly received placebo (0.9% saline; n=26) or an i.v. bolus of ketamine (0.5 mg/kg; n=26) during anesthetic induction. Anesthesia was maintained with isoflurane and fentanyl. A nonsurgical group (n=26) was also included as control. Recent verbal and nonverbal memory and executive functions were assessed before and 1 week after surgery or a 1-week waiting period for the nonsurgical controls. Serum C-reactive protein (CRP) concentrations were determined before surgery and on the first post-operative day. Results: Baseline neurocognitive and depression scores were similar in the placebo, ketamine, and nonsurgical control groups. Cognitive performance after surgery decreased by at least 2 SDs (z-score of 1.96) in 21 patients in the placebo group and only in seven patients in the ketamine group compared with the nonsurgical controls (P<0.001, Fisher's exact test). Cognitive performance was also significantly different between the placebo- and the ketamine-treated groups based on all z-scores (P<0.001, Mann–Whitney U-test). Pre-operative CRP concentrations were similar (P<0.33, Mann–Whitney U-test) in the placebo- and ketamine-treated groups. The post-operative CRP concentration was significantly (P<0.01, Mann–Whitney U-test) lower in the ketamine-treated than in the placebo-treated group. Conclusions: Ketamine attenuates POCD 1 week after cardiac surgery and this effect may be related to the anti-inflammatory action of the drug.

Prehospital therapeutic hypothermia for comatose survivors of cardiac arrest: a randomized controlled trial.

Abstract: BACKGROUND: Intravenous infusion of ice-cold fluid is considered a feasible method to induce mild therapeutic hypothermia in cardiac arrest survivors. However, only one randomized controlled trial evaluating this treatment exists. Furthermore, the implementation rate of prehospital cooling is low. The aim of this study was to evaluate the efficacy and safety of this method in comparison with conventional therapy with spontaneous cooling often observed in prehospital patients. METHODS: A randomized controlled trial was conducted in a physician-staffed helicopter emergency medical service. After successful initial resuscitation, patients were randomized to receive either +4 degrees C Ringer's solution with a target temperature of 33 degrees C or conventional fluid therapy. As an endpoint, nasopharyngeal temperature was recorded at the time of hospital admission. RESULTS: Out of 44 screened patients, 19 were analysed in the treatment group and 18 in the control group. The two groups were comparable in terms of baseline characteristics. The core temperature was markedly lower in the hypothermia group at the time of hospital admission (34.1+/-0.9 degrees C vs. 35.2+/-0.8 degrees C, P<0.001) after a comparable duration of transportation. Otherwise, there were no significant differences between the groups regarding safety or secondary outcome measures such as neurological outcome and mortality. CONCLUSION: Spontaneous cooling alone is insufficient to induce therapeutic hypothermia before hospital admission. Infusion of ice-cold fluid after return of spontaneous circulation was found to be well tolerated and effective. This method of cooling should be considered as an important first link in the 'cold chain' of prehospital comatose cardiac arrest survivors.

Relaxing music as pre-medication before surgery: a randomised controlled trial

Abstract: Introduction: Patients who await surgery often suffer from fear and anxiety, which can be prevented by anxiolytic drugs. Relaxing music may be an alternative treatment with fewer adverse effects. This randomised clinical trial compared pre-operative midazolam with relaxing music. Method: Three hundred and seventy-two patients scheduled for elective surgery were randomised to receive pre-operative prevention of anxiety by 0.05–0.1 mg/kg of midazolam orally or by relaxing music. The main outcome measure was the State Trait Anxiety Inventory (STAI X-1), which was completed by the patients just before and after the intervention. Results: Of the 177 patients who completed the music protocol, the mean and (standard deviation) STAI-state anxiety scores were 34 (8) before and 30 (7) after the intervention. The corresponding scores for the 150 patients in the midazolam group were 36 (8) before and 34 (7) after the intervention. The decline in the STAI-state anxiety score was significantly greater in the music group compared with the midazolam group (P<0.001, 95% confidence interval range −3.8 to −1.8). Conclusion: Relaxing music decreases the level of anxiety in a pre-operative setting to a greater extent than orally administrated midazolam. Higher effectiveness and absence of apparent adverse effects makes pre-operative relaxing music a useful alternative to midazolam for pre-medication.

Platelet concentrates transfusion in cardiac surgery and platelet function assessment by multiple electrode aggregometry.

Abstract: Background: Platelet dysfunction contributes to the pathophysiology of bleeding complications during and after cardiac surgery. In most surgical institutions, no peri-operative point-of-care monitoring of platelet function is used. We evaluated the usefulness of the Multiplate® platelet function analyser based on impedance aggregometry for identifying groups of patients at a high risk of transfusion of platelet concentrates (PC). Methods: Platelet function parameters were determined in 60 patients before and after routine cardiac surgery. Impedance aggregometry measurements were performed on Multiplate® using ADP (ADPtest), collagen (COLtest) and thrombin receptor activating peptide (TRAPtest) as platelet activators. The correlations between the aggregometry results and the transfusion of PC were calculated. The results of the aggregation tests were also divided into tertiles and the differences in PC transfusion between the low and the high tertile were assessed. Results: Low aggregometry delimited groups of patients with significantly higher PC transfusion. In the receiver operating characteristic curve, low pre-operative aggregation in the ADPtest identified patients with high total transfusion of PC (area under the curve 0.74, P=0.001), while the ADPtest performed at the end of the operation identified patients with high PC transfusion on the intensive care unit (ICU) (area under the curve 0.76, P=0.002). Conclusions: Near-patient platelet aggregation may allow the identification of patients with enhanced risk of PC transfusion, both pre-operatively and upon arrival on the ICU.

Pregabalin and dexamethasone in combination with paracetamol for postoperative pain control after abdominal hysterectomy. A randomized clinical trial

Abstract: Background: Multimodal analgesia may be important for optimal postoperative pain treatment and facilitation of early mobilization and recovery. We investigated the analgesic effect of pregabalin and dexamethasone in combination with paracetamol after abdominal hysterectomy. Methods: One hundred and sixteen patients were randomly assigned to either group A (paracetamol+placebo × 2), group B (paracetamol+pregabalin+placebo) or group C (paracetamol+pregabalin+dexamethasone). According to randomization and preoperatively, patients received paracetamol 1000 mg, pregabalin 300 mg, dexamethasone 8 mg or placebo. General anaesthesia was performed. Postoperative pain treatment was paracetamol 1000 mg × 4 and patient-controlled intravenous morphine, 2.5 mg bolus. Nausea was treated with ondansetron. Morphine consumption, pain score (visual analogue scale) at rest and during mobilization, nausea, sedation, dizziness, number of vomits and consumption of ondansetron were recorded 2, 4 and 24 h after the operation. P<0.05 was considered statistically significant. Results: The 24-h morphine consumption and pain score, both at rest and during mobilization, were not significantly different between treatment groups. The mean nausea score (P=0.002) was reduced in group C vs. A. The number of vomits was significantly reduced in both group B (P=0.041) and C (P=0.001) vs. A. Consumption of ondansetron was reduced in group C vs. A and B (P<0.001). Other side effects were not different between groups. Conclusion: Combinations of paracetamol and pregabalin, or paracetamol, pregabalin and dexamethasone did not reduce morphine consumption and pain score compared with paracetamol alone for patients undergoing abdominal hysterectomy. Dexamethasone reduced nausea, vomiting and use of ondansetron.

Adding gabapentin to a multimodal regimen does not reduce acute pain, opioid consumption or chronic pain after total hip arthroplasty.

Abstract: Background: Gabapentin (GPN) is effective in reducing post-operative pain and opioid consumption, but its effects with regional anesthesia for total hip arthroplasty (THA) are not known. We designed this study to determine whether (1) gabapentin administration reduces pain and opioid use after THA using a multimodal analgesic regimen including spinal anesthesia; (2) pre-operative administration of gabapentin is more effective than post-operative administration. Methods: After REB approval and informed consent, 126 patients were enrolled in a double-blinded, randomized-controlled study. Patients received acetaminophen 1 g per os (p.o.), celecoxib 400 mg p.o. and dexamethasone 8 mg intravenously, 1-2h pre-operatively. Patients were randomly assigned to one of three treatment groups (G1: Placebo/Placebo; G2: GPN/Placebo; G3: Placebo/GPN). Patients received gabapentin 600 mg (G2) or placebo (G1 and G3) 2 h before surgery. All patients had spinal anesthesia [15 mg (3cc) of 0.5% hypobaric bupivacaine with 10 μg of fentanyl]. In the post-anesthetic care unit, patients received gabapentin 600 mg (G3) or placebo (G1 and G2). On the ward, patients received acetaminophen 1000 mg p.o. q6h, celecoxib 200 mg p.o. q12h and a morphine PCA device. Patients were interviewed 6 months post-surgery to determine the incidence and severity of chronic post-surgical pain. Results: Mean ± SD cumulative morphine (mg) consumption (G1 = 49.4 ± 24.8, G2 = 47.2 ± 30.1 and G3 = 56.1 ± 38.2) at 48 h and pain scores at 12, 24, 36 and 48 h post-surgery were not significantly different among the groups [G1 (n = 38), G2 (n = 38) and G3 (n = 38)]. Side effect profiles were similar across groups. Six months after surgery, the number of patients who reported chronic post-surgical pain (G1 = 10, G2 = 12 and G3 = 9) and the severity of the pain (G1 = 4.2 ± 2.9, G2 = 4.1 ± 2.2 and G3 = 4.9 ± 2.2) did not differ significantly among the groups (P > 0.05). Conclusions: A single 600 mg dose of gabapentin given pre-operatively or post-operatively does not reduce morphine consumption or pain scores in hospital or at 6 months after hip arthroplasty within the context of spinal anesthesia and a robust multimodal analgesia regimen.

Pulse oximeter perfusion index as an early indicator of sympathectomy after epidural anesthesia

Abstract: Background: The pulse oximeter perfusion index (PI) has been used to indicate sympathectomy-induced vasodilatation. We hypothesized that pulse oximeter PI provides an earlier and clearer indication of sympathectomy following epidural anesthesia than skin temperature and arterial pressure. Methods: Forty patients received lumbar epidural catheters. Patients were randomized to receive either 10 ml 0.5% bupivacaine or 10 ml 0.25% bupivacaine. PI in the toe, mean arterial pressure (MAP) and toe temperature were all assessed at baseline and at 5, 10 and 20 min following epidural anesthesia. The effect of epidural anesthesia over time was assessed by repeated measures analysis of variance. Additionally, we defined clinically evident sympathectomy criteria (a 100% increase in the PI, a 15% decrease in MAP and a 1 °C increase in toe temperature). The numbers of patients demonstrating these changes for each test were compared using the McNemar test for each time point. Results: Twenty-nine subjects had photoplethysmography signals that met a priori signal quality criteria for analysis. By 20 min, PI increased by 326%, compared with a 10% decrease and a 3% increase in MAP and toe temperature, respectively. For PI 15/29, 26/29 and 29/29 of the subjects met the sympathectomy criteria at 5, 10 and 20 min, respectively, compared with 4/29, 6/29 and 18/29 for MAP changes and 3/29, 8/29 and 14/29 for toe temperature changes. Conclusions: PI was an earlier, clearer and more sensitive indicator of the development of epidural-induced sympathectomy than either skin temperature or MAP.

Nitric oxide and pain: ‘Something old, something new’

Abstract: Challenges have emerged following the revival of nitric oxide (NO) from 'something old', a simple gas derived from nitrogen and oxygen with a role in the early stages of evolution, into 'something new', an endogenously formed biological mediator regulating a wide variety of physiological functions. Although pain is a common sensation, it encompasses multiple neurobiologic components, of which NO is only one. In pain research, the study of NO is complicated by convoluted problems related mostly to the effects of NO, which are pro- or anti-nociceptive depending on the circumstances. This dual function reflects the multi-faceted roles of the NO molecule described in physiology. This review covers current information about NO and its implications in pain mechanisms. In addition, it follows the pain pathways, demonstrating the role of NO in peripheral nociceptive transmission as well in central sensitization. This knowledge may provide the scientific basis for developing new drugs that are indicated for different types of pain, drugs that may be related to the chemical links of NO. A comprehensive approach to understanding the effects of NO will help clinicians identify novel agents that combine the pharmacological profile of native drugs with a controllable manner of NO release. Inhibitors of NO synthesis may have analgesic effects and would be of interest for treating inflammatory and neuropathic pain. Unfortunately, only a few of these compounds have reached the stage of clinical pain trials.

ECMO in ARDS: a long‐term follow‐up study regarding pulmonary morphology and function and health‐related quality of life

Abstract: Background: A high survival rate can be achieved in patients with severe acute respiratory distress syndrome (ARDS) using extracorporeal membrane oxygenation (ECMO). The technique and the costs are, however, debated and follow-up studies in survivors are few. The aim of this study was to evaluate long-term pulmonary health after ECMO and severe ARDS. Methods: Twenty-one long-term survivors of severe ARDS and ECMO were studied in a follow-up program including high-resolution computed tomography (HRCT) of the lungs, extensive pulmonary function tests, pulmonary scintigraphy and the pulmonary disease-specific St George’s Respiratory Questionnaire (SGRQ). Results: The majority of patients had residual lung parenchymal changes on HRCT suggestive of fibrosis, but the extension of morphologic abnormalities was limited and without the typical anterior localization presumed to indicate ventilator-associated lung injury. Pulmonary function tests revealed good restitution with mean values in the lower normal range, while T 1 for outwash of inhaled isotope was abnormal in all patients consistent with subclinical obstructivity. Most patients had reduced healthrelated quality of life (HRQoL), according to the SGRQ, but were stating less respiratory symptoms than conventionally treated ARDS patients in previous studies. The majority were integrated in normal work. Conclusion: The majority of ECMO-treated ARDS patients have good physical and social functioning. However, lung parenchymal changes on HRCT suggestive of fibrosis and minor pulmonary function abnormalities remain common and can be detected more than 1 year after ECMO. Furthermore, most patients experience a reduction in HRQoL due to the pulmonary sequelae.

A comparison of ultrasound-guided supraclavicular and infraclavicular blocks for upper extremity surgery.

Abstract: Background: Ultrasound (US)-guided supraclavicular or infraclavicular blocks are commonly used for upper extremity surgery. The aims of this randomized study were to compare the block performance and onset times, effectiveness, incidence of adverse events and patient's acceptance of US-guided supraclavicular or infraclavicular blocks. We hypothesized that the supraclavicular approach, being more superficial and easier to visualize using a 10 MHz transducer, will produce a faster and a more extensive sensory block. Methods: One hundred and twenty patients were randomized to two equal groups: supraclavicular (S) and infraclavicular (I). Each patient received a mixture containing equal volumes of ropivacaine 7.5 mg/ml and mepivacaine 20 mg/ml with adrenaline 5 μg/ml, 0.5 ml/kg body weight (minimum 30 ml, maximum 50 ml). The sensory score (anaesthesia – 2 points, analgesia – 1 point and pain – 0 point) of the seven terminal nerves was assessed every 10 min. Patients were declared ready for surgery when they had an effective surgical block – anaesthesia or analgesia of the five nerves below the elbow. Thirty minutes after the block, the unblocked nerves were supplemented. The block performance and latency times, surgical effectiveness, adverse events and patient's acceptance were recorded. Results: Significantly more patients in the I group were ready for surgery 20 and 30 min after the block. The mean block performance time was 5.7 min in the S group and 5.0 min in the I group (NS). Block effectiveness was superior in the I group: 93% vs. 78% in the S group (P=0.017). The S group patients had a significantly poorer block of the median and ulnar nerves, but a better block of the axillary nerve. Sensory scores at 10, 20 and 30 min were not significantly different. Thirty-two patients in the S group vs. nine patients in the I group experienced transient adverse events (P<0.0001). Patients' acceptance of the block was similar in both groups. Conclusions: Infraclavicular block had a faster onset, better surgical effectiveness and fewer adverse events. Block performance time and patients' acceptance of the procedure were similar in both groups.

The early IL-6 and IL-10 response in trauma is correlated with injury severity and mortality

Abstract: BACKGROUND: Trauma has previously been shown to influence interleukin (IL)-6 and IL-10 levels, but the association of injury severity and mortality with IL-6 and IL-10 responses in the early phase of accidental trauma remains to be investigated. We wished to describe serum levels of IL-6 and IL-10 in the first 24 h after trauma and to assess the relationship with severity of injury and mortality. METHODS: Prospective, descriptive cohort study in a Level 1 trauma centre, Copenhagen, Denmark. We included 265 consecutive adult trauma patients admitted directly from the accident scene during an 18-month period. Serum levels of IL-6 and IL-10 were measured upon arrival and at 6, 12, and 24 h after admittance using an enzyme-linked immunosorbent assay. Correlation analysis was used to assess the relationship between Injury Severity Score (ISS) and levels of IL-6 and IL-10. Analysis of variance was used to describe the IL-6 and IL-10 concentrations in relation to 30-day mortality in a mixed-effect model repeated measures analysis. RESULTS: Mortality was 10.9% (29/265) at 30 days. A significant increase of both IL-6 and IL-10 concentrations was found over time, and a significant correlation was found between ISS and the levels of both IL-6 and IL-10 at all sampling points. Serum concentrations of IL-6 and IL-10 were significantly higher in patients not surviving 30 days (P Language: en

Brain death and its implications for management of the potential organ donor.

Abstract: The systemic physiologic changes that occur during and after brain death affect all organs suitable for transplantation. Major changes occur in the cardiovascular, pulmonary, endocrine, and immunological systems, and, if untreated may soon result in cardiovascular collapse and somatic death. Understanding these complex physiologic changes is mandatory for developing effective strategies for donor resuscitation and management in such a way that the functional integrity of potentially transplantable organs is maintained. This review elucidates these physiological changes and their consequences, and based on these consequences the rationale behind current medical management of brain-dead organ donors is discussed.

The effect of pneumoperitoneum in the steep Trendelenburg position on cerebral oxygenation.

Abstract: Background: daVinci R robot-assisted laparoscopic radical prostatectomy (RALP) requires pneumoperitoneum in the steep Trendelenburg position, which results in increased intracranial pressure and cerebral blood flow. The aim of this study was to evaluate the effect of pneumoperitoneum in a 30° Trendelenburg position on cerebral oxygenation using regional cerebral oxygen saturation (rSO 2 ). Methods: Thirty-two male patients of ASA I and II physical status without previous episodes of cerebral ischemia or hemorrhage undergoing daVinci ® RALP were enrolled. The rSO 2 was continuously monitored with near-infrared spectroscopy (INVOS" 5100 ™ ) during the study period. Measurements were obtained immediately after anesthesia induction (TO; baseline), 5 min after a 30° Trendelenburg position (T1), 5 min after 15 mmHg pneumoperitoneum in a supine position (T2), 30, 60 and 120 min after the pneumoperitoneum in a Trendelenburg position (T3, T4 and T5, respectively) and after desufflation in a supine position (T6). Results: The change in the left and right rSO 2 was statistically significant (Left P = 0.004 and Right P = 0.023). Both the right and the left rSO 2 increased significantly during pneumoperitoneum in a Trendelenburg position (from T3 to T5) and at T6 compared with the baseline value at T0. The partial pressure of carbon dioxide (PaCO 2 ) was increased significantly at T2, T3, T5 and T6 compared with the baseline value at T0. Conclusions: During daVinci ® RALP, cerebral oxygenation, as assessed by rSO 2 , increased slightly, which suggests that the procedure did not induce cerebral ischemia. The PaCO 2 should be maintained within the normal limit during pneumoperitoneum in a Trendelenburg position in patients undergoing daVinci ® RALP because the rSO 2 increased in conjunctions with the increase in PaCO 2 .

Photoplethysmography and nociception.

Abstract: Photoplethysmography (PPG), i.e. pulse oximetric wave, is a non-invasive technique that is used in anaesthesia monitoring primarily to monitor blood oxygenation. The PPG waveform resembles that of the arterial blood pressure but instead of pressure it is related to the volume changes in the measurement site and hence contains information related to the peripheral blood circulation, including skin vasomotion, which is controlled by the sympathetic nervous system. Because of this link, skin vasomotor response and PPG amplitude response have been associated with nociception under general anaesthesia. Recently, there has been interest in monitoring nociception during general anaesthesia. In many of the published studies, PPG waveform information has been included. The focus of this topical review is to provide an overview on the information embedded in the PPG waveform especially in the context of the autonomic nervous system and analgesia monitoring.

Effects of dexmedetomidine or methylprednisolone on inflammatory responses in spinal cord injury

Abstract: Background: The aim of this study was to compare the anti-inflammatory response of methylprednisolone and the α2-agonist dexmedetomidine in spinal cord injury (SCI). Methods: Twenty-four male adult Wistar albino rats, weight 200–250 g, were included in the study. The rats were divided into four groups as follows: the control group (n: 6) received only laminectomy; the SCI group (n: 6) with trauma alone; the SCI+methylprednisolone group (n: 6) with trauma and 30 mg/kg methylprednisolone, followed by a maintenance dose of 5.4 mg/kg/h; and the SCI+dexmedetomidine group (n: 6) with trauma and 10 μg/kg dexmedetomidine treatment intraperitoneally. Twenty-four hours after the trauma, spinal cord samples were taken for histopathological examination and serum samples were collected for interleukin-6 (IL-6) and tumor necrosis factor (TNF)-α measurement. Results: TNF-α (P=0.009) and IL-6 (P=0.009) levels were significantly increased in the SCI group. TNF-α and IL-6 levels were significantly decreased with methylprednisolone (P=0.002, 0.002) and dexmedetomidine (P=0.002, 0.009) treatment, respectively. Methylprednisolone and dexmedetomidine treatment reduced neutrophils' infiltration in SCI. Conclusions: The current study does not clarify the definitive mechanism by which dexmedetomidine decreases inflammatory cytokines but it is the first study to report the anti-inflammatory effect of dexmedetomidine in SCI. Further studies are required to elucidate the effects of dexmedetomidine on the inflammatory response.

The I-gel, a single-use supraglottic airway device with a non-inflatable cuff and an esophageal vent: an observational study in children.

Abstract: Background: The I-gel® is a new single-use supraglottic airway device with a non-inflatable cuff. It is composed of a thermoplastic elastomer and a soft gel-like cuff that adapts to the hypopharyngeal anatomy. Like the LMA-ProSeal, it has an airway tube and a gastric drain tube. Little is known about its efficiency in pediatric anesthesia. Methods: Fifty children above 30 kg, ASA I–II, undergoing a short-duration surgery were included in this prospective, observational study. We evaluated ease in inserting the I-gel®, seal pressure, gastric leak, complications during insertion and removal, ease in inserting the gastric tube and ventilatory parameters during positive pressure ventilation. Results: All devices were inserted at the first attempt. The mean seal pressure was 25 cmH2O. There was no gastric inflation and gastric tube insertion was achieved in all cases. The results appear similar to those in a previous study concerning laryngeal mask airway in terms of leak pressure and complication rates. Conclusion: Because the I-gel® has a very good insertion success rate and very few complications, it seems to be an efficient and safe device for pediatric airway management.

The incidence of intra-operative awareness during general anesthesia in China: a multi-center observational study.

Abstract: Background: The incidence of awareness in patients undergoing general anesthesia is 0.1–0.2% in Western countries. The medical literatures about awareness during general anesthesia are still rare in China, but some previous studies have reported a higher incidence (1.4–6%) of intra-operative awareness. To find out the reason why the incidence reported in China is much higher than that in Western countries, we performed a prospective, multicenter, non-randomized observational study to determine the true incidence of intra-operative awareness in China. Methods: This is a prospective, non-randomized descriptive cohort study that was conducted at 25 academic medical centers in China. Eleven thousand one hundred and eighty-five patients were interviewed by research staff for evaluation of awareness at the first and fourth day after general anesthesia with muscle relaxation. An independent blinded committee evaluated the responses and determined whether awareness occurred. Necessary data were collected for a binary logistic regression analysis. Results: Data from 11,101 patients were presented. Forty-six cases (0.41%) were reported as definite awareness and 47 additional cases (0.41%) as possible awareness. Three hundred and fifty-five patients (3.19%) had dreams during general anesthesia. Awareness was associated with increased American Society of Anesthesiologists (ASA) physical status, a previous anesthesia, and anesthesia methods of total intravenous anesthesia. Conclusion: The incidence of intra-operative awareness in China is approximately 0.41%, two to three times higher than that widely cited in Western countries. Inappropriately light anesthesia, and the population proportion of surgery and general anesthesia in China may account for the difference. (ClinicalTrials.gov Identifier, NCT00693875.)

Analgesia before a spinal block for femoral neck fracture: fascia iliaca compartment block.

Abstract: BACKGROUND In this prospective randomized study, the authors compared the analgesic effect of a fascia iliaca compartment (FIC) block with that of intravenous (i.v.) alfentanil when administered to facilitate positioning for spinal anaesthesia in elderly patients undergoing surgery for a femoral neck fracture. METHODS The 40 patients were randomly assigned to one of two groups, namely, the FIC group (fascia iliaca compartment block, n=20) and the IVA group (intravenous analgesia with alfentanil, n=20). Group IVA patients received a bolus dose of i.v. alfentanil 10 microg/kg, followed by a continuous infusion of alfentanil 0.25 microg/kg/min starting 2 min before the spinal block, and group FIC patients received a FIC block with 30 ml of ropivacaine 3.75 mg/ml (112.5 mg) 20 min before the spinal block. Visual analogue pain scale (VAS) scores, time to achieve spinal anaesthesia, quality of patient positioning, and patient acceptance were compared. RESULTS VAS scores during positioning (mean and range) were lower in the FIC group than in the IVA group [2.0 (1-4) vs. 3.5 (2-6), P=0.001], and the mean (+/- SD) time to achieve spinal anaesthesia was shorter in the FIC group (6.9 +/- 2.7 min vs. 10.8 +/- 5.6 min; P=0.009). Patient acceptance (yes/no) was also better in the FIC group (19/1) than in the IVA group (12/8)(P=0.008). CONCLUSIONS An FIC block is more efficacious than i.v. alfentanil in terms of facilitating the lateral position for spinal anaesthesia in elderly patients undergoing surgery for femoral neck fractures.

Scandinavian clinical practice guidelines for therapeutic hypothermia and post-resuscitation care after cardiac arrest.

Abstract: Background and aim: Sudden cardiac arrest survivors suffer from ischaemic brain injury that may lead to poor neurological outcome and death. The reperfusion injury that occurs is associated with damaging biochemical reactions, which are suppressed by mild therapeutic hypothermia (MTH). In several studies MTH has been proven to be safe, with few complications and improved survival, and is recommended by the International Liaison of Committee on Resuscitation. The aim of this paper is to recommend clinical practice guidelines for MTH treatment after cardiac arrest from the Scandinavian Society of Anaesthesiology and Intensive Care Medicine (SSAI). Methods: Relevant studies were identified after two consensus meetings of the SSAI Task Force on Therapeutic Hypothermia (SSAITFTH) and via literature search of the Cochrane Central Register of Controlled Trials and Medline. Evidence was assessed and consensus opinion was used when high-grade evidence (Grade of Recommendation, GOR) was unavailable. A management strategy was developed as a consensus from the evidence and the protocols in the participating countries. Results and conclusion: Although proven beneficial only for patients with initial ventricular fibrillation (GOR A), the SSAITFTH also recommend MTH after restored spontaneous circulation, if active treatment is chosen, in patients with initial pulseless electrical activity and asystole (GOR D). Normal ethical considerations, premorbid status, total anoxia time and general condition should decide whether active treatment is required or not. MTH should be part of a standardized treatment protocol, and initiated as early as possible after indication and treatment have been decided (GOR E). There is insufficient evidence to make definitive recommendations among techniques to induce MTH, and we do not know the optimal target temperature, duration of cooling and rewarming time. New studies are needed to address the question as to how MTH affects, for example, prognostic factors.

Intravenous magnesium sulfate for post-operative pain in patients undergoing lower limb orthopedic surgery.

Abstract: Introduction: This study looks at the effect of supplementary intravenous magnesium sulfate on acute pain when administered in patients undergoing lower limb orthopedic surgery using spinal anesthesia with bupivacaine. Method and materials: In this double-blind, randomized, placebo-controlled clinical trial, 60 patients were selected and randomly divided into two groups. Efforts were made to place both groups under the same method of anesthesia. One group received 8 mg/kg intravenous magnesium sulfate, started before the incision and continued up to the end of the surgical procedure, using a 50 ml syringe, via a peripheral large bore catheter; the second group received the same volume of placebos using the same method. To present the results, mean (± SD) was used; a P value of <0.05 was considered significant. Results: There was no difference between the two groups in terms of the basic variables. Pain reported by the first group that received magnesium sulfate was significantly less at the first, third, sixth and 12th hours after the operation in comparison with the group that received placebo. Also, the intravenous morphine requirements in the first 24 h after the surgery were less in the magnesium group (4.2 ± 1.6 mg) than in the control group (9.8 ± 2.1 mg). Conclusion: Intravenous magnesium sulfate can serve as a supplementary analgesic therapy to suppress the acute post-operative pain, leading to less morphine requirements in the first 24 h.

Comparison of closed loop vs. manual administration of propofol using the Bispectral index in cardiac surgery.

Abstract: Background: In recent years, electroencephalographic indices of anaesthetic depth have facilitated automated anaesthesia delivery systems. Such closed-loop control of anaesthesia has been described in various surgical settings in ASA I–II patients (1–4), but not in open heart surgery characterized by haemodynamic instability and higher risk of intra-operative awareness. Therefore, a newly developed closed-loop anaesthesia delivery system (CLADS) to regulate propofol infusion by the Bispectral index (BIS) was compared with manual control during open heart surgery. Methods: Forty-four adult ASA II–III patients undergoing elective cardiac surgery under cardiopulmonary bypass were enrolled. The study participants were randomized to two groups: the CLADS group received propofol delivered by the CLADS, while in the manual group, propofol delivery was adjusted manually. The depth of anaesthesia was titrated to a target BIS of 50 in both the groups. Results: During induction, the CLADS group required lower doses of propofol (P<0.001), resulting in lesser overshoots of BIS (P<0.001) and mean arterial blood pressure (P=0.004). Subsequently, BIS was maintained within ± 10 of the target for a significantly longer time in the CLADS group (P=0.01). The parameters of performance assessment, median absolute performance error (P=0.01), wobble (P=0.04) and divergence (P<0.001), were all significantly better in the CLADS group. Haemodynamic stability was better in the CLADS group and the requirement of phenylephrine in the pre-cardiopulmonary bypass period as well as the cumulative dose of phenylephrine used were significantly higher in the manual group. Conclusion: The automated delivery of propofol using CLADS was safe, efficient and performed better than manual administration in open heart surgery.

Single transpulmonary thermodilution and continuous monitoring of central venous oxygen saturation during off-pump coronary surgery.

Abstract: Background: Off-pump coronary artery bypass grafting (OPCAB) requires thorough monitoring of hemodynamics and oxygen transport. Our aim was to fi nd out whether therapeutic guidance during and after OPCAB, using an algorithm based on advanced monitoring, influences perioperative hemodynamic and fluid management as well as the length of post-operative ICU and hospital stay. Methods: Patients were randomized into two groups of hemodynamic monitoring: the conventional monitoring (CM) group (n 5 20) and the advanced monitoring (AM) group (n 5 20). In the CM group, therapy was guided by central venous pressure, mean arterial pressure (MAP) and heart rate (HR), and in the AM group by the intrathoracic blood volume index, MAP, HR, central venous oxygen saturation (ScvO2) and cardiac index (CI). The measurements were performed before and during surgery, and at 2, 4a nd 6 h post-operatively. Results: In the AM group, colloids and dobutamine were given more frequently and were accompanied by increments in ScvO2, CI and oxygen delivery compared with baseline. The percentage of ephedrine administration was higher in the CM group. The algorithm guided by AM decreased time until achieving the status of ‘fit for ICU discharge’ and post-operative hospital stay by 15% and 25%, respectively. Conclusions: A goal-directed algorithm based on advanced hemodynamic monitoring and continuous measurement of ScvO2 facilitates early detection and correction of hemodynamic changes and influences the strategy for fluid therapy that can improve the course of post-operative period after coronary artery bypass grafting on the beating heart.

A new supraglottic airway device: LMA-supreme, comparison with LMA-Proseal.

Abstract: Background and objective: The LMA-Supreme™ (S-LMA™) is a new supraglottic airway device that presents combined features of flexibility, curved structure and single use and a different cuff structure. The purpose of this study was to compare the oropharyngeal leak pressures (OLP) of LMA-Proseal™ (P-LMA™) and S-LMA™. Methods: Sixty adult patients were prospectively and randomly allocated to undergo insertion of P-LMA™ (n=30) or S-LMA™ (n=30). The cuffs were inflated until the intracuff pressure (ICP) reached 60 cm H2O. Orogastric leak pressures, insertion times, first attempt success rates, fiberoptical assessment of position, cuff pressures, orogastric tube (OGT) placement and OGT insertion times were compared. Unblinded observers collected intraoperative data and blinded observers collected post-operative data. Results: The first insertion attempts and time taken to provide an effective airway were similar between the groups. Two patients (P-LMA™, n=1; S-LMA™, n=1) were intubated due to excessive oropharyngeal leak and in one patient (P-LMA™, n=1) due to failed OGT placement. OLPs were similar (P-LMA™; 26.9±6.6 S-LMA™; 26.1±5.2). ICP increased significantly in the P-LMA™ at the 30 and 60 min during anesthesia (P-LMA™; 80.1±12.8, 92.9±14.4, S-LMA™; 68.3±10.9, 73.7±15.6). OGT placement was successful in all patients in the S-LMA™, but failed in five patients in the P-LMA™ (P=0.02). Fiberoptically determined anatomic position was better with the P-LMA™ (P=0.03). Conclusion: Our findings suggest that S-LMA™ had leak pressures similar to the P-LMA™, and this new airway device proved to be successful during both spontaneous and positive pressure ventilation.