Showing papers in "Acta Anaesthesiologica Scandinavica in 2008"

Electroencephalogram spindle activity during dexmedetomidine sedation and physiological sleep

Abstract: Background: Dexmedetomidine, a selective α2-adrenoceptor agonist, induces a unique, sleep-like state of sedation. The objective of the present work was to study human electroencephalogram (EEG) sleep spindles during dexmedetomidine sedation and compare them with spindles during normal physiological sleep, to test the hypothesis that dexmedetomidine exerts its effects via normal sleep-promoting pathways. Methods: EEG was continuously recorded from a bipolar frontopolar–laterofrontal derivation with Entropy Module (GE Healthcare) during light and deep dexmedetomidine sedation (target-controlled infusions set at 0.5 and 3.2 ng/ml) in 11 healthy subjects, and during physiological sleep in 10 healthy control subjects. Sleep spindles were visually scored and quantitatively analyzed for density, duration, amplitude (band-pass filtering) and frequency content (matching pursuit approach), and compared between the two groups. Results: In visual analysis, EEG activity during dexmedetomidine sedation was similar to physiological stage 2 (S2) sleep with slight to moderate amount of slow-wave activity and abundant sleep spindle activity. In quantitative EEG analyses, sleep spindles were similar during dexmedetomidine sedation and normal sleep. No statistically significant differences were found in spindle density, amplitude or frequency content, but the spindles during dexmedetomidine sedation had longer duration (mean 1.11 s, SD 0.14 s) than spindles in normal sleep (mean 0.88 s, SD 0.14 s; P=0.0014). Conclusions: Analysis of sleep spindles shows that dexmedetomidine produces a state closely resembling physiological S2 sleep in humans, which gives further support to earlier experimental evidence for activation of normal non-rapid eye movement sleep-promoting pathways by this sedative agent.

Ultrasound-guided peripheral nerve blocks : What are the benefits?

Abstract: Background: Use of ultrasound by anaesthesiologists performing regional blocks is rapidly gaining popularity. The aims of this review were to summarize and update accumulating evidence on ultrasound-guided nerve blocks, with an emphasis on the clinical relevance of the results and to critically appraise changing standards in regional anaesthesia. Methods: A search of MEDLINE and EMBASE (1966 to 31 December 2007) was conducted using the following free terms: ‘ultrasound and regional anesthesia’, ‘ultrasound and peripheral block’ and ‘ultrasound and nerve and block’. These were combined with the MESH terms ‘nerve block’ and ‘ultrasonography’. The following limits were applied: studies with abstracts, only in humans, published in core clinical journals. Trial type: meta-analysis, randomized-controlled trial and clinical trial. Results: When peripheral nerves are adequately imaged by ultrasound, the concomitant use of nerve stimulation offers no further advantage. However, several studies reported problems with obtaining satisfactory images in some patients. Ultrasound guidance significantly shortened the block performance time and/or reduced the number of needle passes to reach the target in all comparative studies. The occurrence of paraesthesia during block performance was also reduced, but not the incidence of short-lasting post-operative neuropraxia. The frequency of accidental vascular punctures may be lower, but the data are contradictory. Block onset time was significantly shortened. Block duration was longer in children, but not in adults. Ultrasound also allowed dose reduction of the local anaesthetic (LA). Conclusions: Ultrasound guidance shortens the block performance time, reduces the number of needle passes and shortens the block onset time. Blocks may be performed using lower LA doses.

Severity scoring in the ICU: a review

Abstract: Department of Surgical Sciences, Facultyof Medicine, University of Bergen, Bergen, NorwayBackground: Patients in the intensive care unit (ICU)requirehugeresourcesbecauseofthedysfunctionofseveral of their vital organs. The heterogeneity and com-plexity of the ICU patient have generated interest insystems able to measure severity of illness as a methodof predicting outcome, comparing quality-of-care andstratification for clinical trials.Methods: By searching Medline and EMBASE for publica-tions describing scoring systems in the ICU, the mostfrequently used systems, defined as resulting in morethan 50 references, are included in this review. Scoringsystems belong to one of four classes prognostic, single-organ failure, trauma scores and organ dysfunction (OD).The different systems are described and discussed.Results: Three different prognostic scoring systems, in-cluding several versions, four single OD scores and threeOD scores, were included in this review.Conclusion: Different forms of scoring systems are fre-quently used in the ICU. They have become a necessarytool to describe ICU populations and to explain differencesin mortality. As there are several pitfalls related to theinterpretation of the numbers supplied by the systems,they should not be used without knowledge on the scienceof severity scoring.

High-volume infiltration analgesia in total knee arthroplasty : a randomized, double-blind, placebo-controlled trial

Abstract: Background: High-volume infiltration analgesia may be effective with a low risk of side effects in hip and knee arthroplasty. The present placebo-controlled study was carried out to evaluate the analgesic effect of high-volume infiltration analgesia in bilateral total knee arthroplasty, along with a detailed description of the infiltration technique. Methods: In a randomized, double-blind, placebo-controlled trial in 12 patients undergoing bilateral knee arthroplasty, saline or high-volume (170 ml) ropivacaine (0.2%) with epinephrine was infiltrated around each knee, with repeated doses administered through an intra-articular catheter for 24 h and pain and opioid requirements assessed for 48 h in a fast-track setting. Results: Pain at rest and during movement was significantly reduced for up to 32 h with the high-volume local anesthetic infiltration technique. No major side effects were observed. The median hospital stay was 4 days. Conclusion: High-volume infiltration analgesia is effective in knee arthroplasty and, due to its simplicity, may be preferable compared with other analgesic techniques in knee arthroplasty.

Pre‐operative carbohydrate loading may be used in type 2 diabetes patients

Abstract: Background: Post-operative insulin resistance and hyperglycaemia are associated with an impaired outcome after surgery. Pre-operative oral carbohydrate loading (CHO) reduces post-operative insulin resistance with a reduced risk of hyperglycaemia during post-operative nutrition. Insulin-resistant diabetic patients have not been given CHO because the effects on pre-operative glycaemia and gastric emptying are unknown.Methods: Twenty-five patients (45-73 years) with type 2 diabetes [glycated haemoglobin (HbA1c) 6.2 +/- 0.2%, mean +/- SEM] and 10 healthy control subjects (45-72 years) were studied. A carbohydrate-rich drink (400 ml, 12.5%) was given with paracetamol 1.5 g for determination of gastric emptying.Results: Peak glucose was higher in diabetic patients than in healthy subjects (13.4 +/- 0.5 vs. 7.6 +/- 0.5 mM; P<0.01) and occurred later after intake (60 vs. 30 min; P<0.01). Glucose concentrations were back to baseline at 180 vs. 120 min in diabetic patients and healthy subjects, respectively (P<0.01). At 120 min, 10.9 +/- 0.7% and 13.3 +/- 1.2% of paracetamol remained in the stomach in diabetic patients and healthy, subjects respectively. Gastric half-emptying time (T50) occurred at 49.8 +/- 2.2 min in diabetics and at 58.6 +/- 3.7 min in healthy subjects (P<0.05). Neither peak glucose, glucose at 180 min, gastric T50, nor retention at 120 min differed between insulin (HbA1c 6.8 +/- 0.7%)- and non-insulin-treated (HbA1c 5.6 +/- 0.4%) patients.Conclusions: Type 2 diabetic patients showed no signs of delayed gastric emptying, suggesting that a carbohydrate-rich drink may be safely administrated 180 min before anaesthesia without risk of hyperglycaemia or aspiration pre-operatively.

Quality of life 2-7 years after major trauma.

Abstract: CentreforClinicalResearch,HaukelandUniversityHospital, Bergen,NorwayBackground: The aim of the present study was to assesspotential long-term reduction in health-related quality oflife (HRQOL) in adult trauma patients 2–7 years afterdischarge from an intensive care unit (ICU), and to studypossible determinants of the HRQOL reduction.Methods: Follow-up study of a cohort of 341 traumapatients admitted to the ICU of a university hospitalduring 1998–2003. Of the 228 eligible patients, 210 (92%)completed the study. A telephone interview using theEuroQol 5-D (EQ-5D) was conducted. Patients reportedtheir HRQOL both at present and before trauma.Results: Before trauma 88% reported in retrospect noproblem in any EQ-5D dimension, compared with 20% atfollow-up. After trauma (median 4.0 years) 58% suffered pain/discomfort, 44% reported alterations in usual activities, 40%reduced mobility, 35% anxiety/depression, and 15% limitedautonomy. A total of 74% experienced reduction in HRQOL.Severe problems were reported by 16%. Women experiencedmore anxiety/depression than men. Simplified Acute Physiol-ogy Score (SAPS) II and Injury Severity Score (ISS) weresignificantly associated with impaired HRQOL, while age wasnot. Patients with severe head injury reported better HRQOLthan those without severe head injury.Conclusion: More than 2 years post-injury, 74% reportedimpaired HRQOL but only 16% had severe problems. Themajority still suffered pain/discomfort, indicating thatpain management is a key factor in improving long-termoutcome after severe trauma.

Blood volume is normal after pre-operative overnight fasting.

Abstract: Background Pre-operative fasting is assumed to cause a deficit in intravascular blood volume (BV), as a result of ongoing urine production and insensible perspiration. Standard regimes consist of volume loading prior or simultaneous to any anaesthetic procedure to minimise the risk of hypotension. However, fluid overload in the context of major abdominal surgery has been shown to deteriorate patient outcome. Our study aimed to quantify total intravascular BV after fasting by direct measurements and to compare it with calculated normal values in comparable non-fasted patients. Methods After 10 h of fasting, total plasma volume (PV) and red cell volume (RCV) were measured via the double-label technique (indocyanine green dilution and erythrocytes labelled with fluorescein, respectively) following induction of general anaesthesia in 53 gynaecological patients suffering from malignoma of the cervix. The corresponding normal values were calculated individually from age, body height and body weight. Results Measured BV, RCV and PV after fasting were 4123+/-589, 1244+/-196 and 2879+/-496 ml, respectively. The differences to the corresponding calculated normal values were not significant (3882+/-366, 1474+/-134 and 2413+/-232 ml, respectively). The measured haematocrit reflected a slight anaemic state (0.35+/-0.03). Conclusion Our data suggest that even after prolonged pre-operative fasting, cardio-pulmonary healthy patients remain intravascularly normovolaemic. Therefore, hypotension associated with induction of general or neuraxial anaesthesia should perhaps be treated with moderate doses of vasopressors rather than with undifferentiated volume loading.

Pre-hospital airway management: guidelines from a task force from the Scandinavian Society for Anaesthesiology and Intensive Care Medicine

Abstract: This article is intended as a generic guide to evidencebased airway management for all categories of pre-hospital personnel. It is based on a review of relevant literature but the majority of the studies have not been performed under realistic, pre-hospital conditions and the recommendations are therefore based on a low level of evidence (D). The advice given depends on the qualifications of the personnel available in a given emergency medical service (EMS). Anaesthetic training and routine in anaesthesia and neuromuscular blockade is necessary for the use of most techniques in the treatment of patients with airway reflexes. For anaesthesiologists, the Task Force commissioned by the Scandinavian Society of Anaesthesia and Intensive Care Medicine recommends endotracheal intubation (ETI) following rapid sequence induction when securing the pre-hospital airway, although repeated unsuccessful intubation attempts should be avoided independent of formal qualifications. Other physicians, as well as paramedics and other EMS personnel, are recommended the lateral trauma recovery position as a basic intervention combined with assisted mask-ventilation in trauma patients. When performing advanced cardiopulmonary resuscitation, we recommend that non-anaesthesiologists primarily use a supraglottic airway device. A supraglottic device such as the laryngeal tube or the intubation laryngeal mask should also be available as a backup device for anaesthesiologists in failed ETI.

Operating room management: why, how and by whom?

Abstract: Operating room (OR) is a cost-intensive environment, and it should be managed efficiently. When improving efficiency, shortening case duration by parallel processing, training of the resident surgeons, the choice of anesthetic methods, effective scheduling, and monitoring of the overall OR performance are important. When redesigning the OR processes, changes should be given a clear target and the achieved results monitored and reported to everyone involved. Advanced, reliable, and easy to use information technology solutions for OR management are under development. Pre-operative clinic and functionally designed facilities support efficiency. OR personnel must be kept motivated by clear management and leadership, supported by superiors.

Use of a screening questionnaire for post‐traumatic stress disorder (PTSD) on a sample of UK ICU patients

Abstract: Background: Although rates vary across studies, research in recent years shows that prevalence of post-traumatic stress disorder (PTSD) following intensive care unit (ICU) can be high. Presently no screening tool assessing all three PTSD symptom categories has been validated in ICU patients. The aim of the study was to conduct a preliminary validation of such a measure, the UK- Post-Traumatic Stress Syndrome 14-Questions Inventory (UK-PTSS-14). Methods: A case series cohort study performed at two ICUs in two UK district general hospitals. The UK-PTSS-14 was administered at three time-points (4-14 days, 2 months and 3 months post-ICU discharge). At time-point three participants also completed the Post-traumatic Stress Diagnostic Scale (PDS) and the Impact of Events Scale (IES). Results: Forty-four patients completed the 3-month follow up. The UK-PTSS-14 was internally reliable at all three time-points (Cronbach's α= 0.89, 0.86 and 0.84, respectively). Test-retest reliability was highest between time-points two and three (ICC = 0.90). Concurrent validity at time-point three was high against the PDS (r = 0.86) and the IES (r = 0.71). Predictive validity was highest at time-point two (r = 0.85 with the PDS and r = 0.71 with the IES). Receiver operator characteristic curve analysis suggested the highest levels of sensitivity (86%) and specificity (97%) for diagnosis of PTSD were at time-point two, with an optimum decision threshold of 45 points. Conclusion: This preliminary validation study suggests that the UK-PTSS-14 could be reliably used as a screening instrument at 2 months post-discharge from the ICU to identify those patients in need of referral to specialist psychological services.

Clinical pharmacology of methadone for pain

Abstract: Background: This topical review addresses methadone's pharmacology, its application in malignant and non-malignant pain conditions, practical issues related to methadone for the treatment of pain and its influence on QTc time. Methods: Relevant papers were identified in PubMed and EMBASE. Results: Methadone is advocated by experts as a second line opioid when first line opioids fail to provide a satisfactory balance between pain control and side effects (opioid switching). Although randomized-controlled studies are lacking, current evidence suggests that switching to methadone in this situation reduces pain intensity. However, interindividual variability in its pharmacokinetics make its application challenging and metabolism by CYP 3A4 and 2B6 implies a substantial risk of drug–drug interactions. Several ways of switching to methadone have been presented, with a gradual switch during 3 days or ‘stop and go’ as the dominating strategies. Episodes of torsade de pointes arrhythmia during methadone treatment have been reported in patients with other risk factors for arrhythmia, while small prospective studies have reported a small, lasting and stable increase in QTc time. The extensive use of methadone for opioid replacement in addicts has added additional patient barriers to its use for pain control. Conclusion: In spite of challenges related to the variable pharmacokinetics and concerns regarding increase in QTc time, current evidence indicates that opioid switching to methadone improves pain control in a substantial proportion of patients who are candidates for opioid switching. Measures must be instituted to secure that patients receiving methadone for pain are not considered opioid addicts.

Improved survival after an out-of-hospital cardiac arrest using new guidelines.

Abstract: Background: An out-of-hospital cardiac arrest (OHCA) is associated with a poor prognosis. We hypothesized that the implementations of 2005 European Resuscitation Council resuscitation guidelines were associated with improved 30-day survival after OHCA. Methods: We prospectively recorded data on all patients with OHCA treated by the Mobile Emergency Care Unit of Copenhagen in two periods: 1 June 2004 until 31 August 2005 (before implementation) and 1 January 2006 until 31 March 2007 (after implementation), separated by a 4-month period in which the above-mentioned change took place. Results: We found that 30-day survival increased after the implementation from 31/372 (8.3%) to 67/419 (16%), P 5 0.001. ROSC at hospital admission, as well as survival to hospital discharge, were obtained in a significantly higher proportion from 23.4% to 39.1%, Po0.0001, and from 7.9% to 16.3%, P 5 0.0004, respectively. Treatment after implementation was confirmed as a significant predictor of better 30-day survival in a logistic regression analysis. Conclusion: The implementation of new resuscitation guidelines was associated with improved 30-day survival after OHCA.

Intravenous remifentanil vs. epidural levobupivacaine with fentanyl for pain relief in early labour: a randomised, controlled, double-blinded study.

Abstract: Background We hypothesised that intravenous patient-controlled analgesia (IV PCA) with remifentanil could provide as satisfactory pain relief for labour as epidural analgesia. Methods Fifty-two parturients with singleton uncomplicated pregnancies were randomised to receive either IV PCA with remifentanil or epidural analgesia with 20 ml levobupivacaine 0.625 mg/ml and fentanyl 2 microg/ml in saline. The PCA dose of remifentanil was given over 1 min with a lockout time of 1 min. The dose was increased starting from the bolus of 0.1 microg/kg and following a dose escalation scheme up until the individual-effective dose was reached. The parturients assessed contraction pain (0-10), pain relief (0-4), sedation and nausea during 60 min. Results Forty-five parturients were included in the analysis. The median cervical opening was 4 cm before the study and 7 cm after the study. The median pain scores were 7.3 and 5.2 during remifentanil and epidural analgesia, respectively (P=0.009). The median pain relief scores were 2.5 and 2.8 (P=0.17). There was no difference between the groups in the proportion of parturients who discontinued due to ineffective analgesia, nor in the proportion of parturients who would have liked to continue the given medication at the end of the study. Sedation and low haemoglobin oxygen saturation were observed more often during remifentanil analgesia. Foetal heart rate tracing abnormalities were as common in both groups. Conclusions In terms of pain scores, epidural analgesia is superior to that provided by IV remifentanil. However, there was no difference in the pain relief scores between the treatments.

Induction of mild hypothermia in cardiac arrest survivors presenting with cardiogenic shock syndrome.

Abstract: Background: Induction of mild hypothermia (MH) in patients resuscitated from cardiac arrest improves their outcome. However, benefits and risks of MH in patients who remain in cardiogenic shock after the return of spontaneous circulation (ROSC) are unclear. We analysed all cardiac arrest survivors who were treated with MH in our intensive coronary care unit (CCU) and compared the outcome of patients with cardiogenic shock syndrome (CSS) with those who were circulatory stable. Methods: We performed retrospective analysis of all consecutive cardiac arrest survivors treated by MH in our CCU from November 2002 to August 2006. They were classified into two groups, according to whether they met the criteria for cardiogenic shock or not before MH initiation. Results: Out of 56 consecutive patients, 28 fulfilled criteria of cardiogenic shock before MH initiation (group A) and 28 were relatively stable (group B). In-hospital mortality was 57.1% in group A and 21.4% in group B patients (P=0.013). Favourable neurological outcome anytime during hospitalization was found in 67.9% of group A patients and in 82.1% of group B subjects (P=0.355). Favourable discharge neurological outcome was reached in 39.3% in group A and in 71.4% in group B (P=0.031). The complication rate in both groups did not differ. Conclusion: While in-hospital mortality in cardiac arrest survivors treated by MH was expectably higher in those with cardiogenic shock than in stable patients, the favourable neurological outcome during hospitalization was comparable in both groups. Therefore, induction of MH should be considered in cardiac arrest survivors with CSS after ROSC.

Surgical stress index as a measure of nociception/antinociception balance during general anesthesia.

Abstract: Background: No validated monitoring method is available for evaluating the nociception/antinociception balance. We assessed the surgical stress index (SSI), computed from finger photoplethysmographic waveform amplitudes and pulse-to-pulse intervals, in patients undergoing shoulder surgery under general anesthesia (GA) and interscalene plexus block and in patients with GA only. Methods: In this prospective, randomized study in 26 patients, increased blood pressure (BP) or heart rate, movement, and coughing were considered to be signs of intraoperative nociception and were treated with alfentanil. GA was maintained with desflurane aiming at a State Entropy level of 50. Photoplethysmographic waveforms were collected from the contra-lateral arm to the surgery and SSI values from 0 (no surgical stress) to 100 (maximal surgical stress) were calculated off-line. Results: Two minutes after skin incision, SSI had not increased in the plexus group and was lower in the plexus group (38 ± 13) compared with the controls (58 ± 13, P<0.005). Among the controls, 1 min before alfentanil administration, the SSI value was higher than during periods of adequate antinociception, 59 ± 11 vs. 39 ± 12 (P<0.01). The total cumulative need for alfentanil was higher in controls (2.7 ± 1.2 mg) compared with the plexus group (1.6 ± 0.5 mg; P=0.008). Tetanic stimulation to the ulnar region of the hand increased SSI significantly only among the patients with plexus block not covering the site of the stimulation. Conclusion: SSI values were lower in patients with plexus block covering the sites of nociceptive stimuli. In detecting nociceptive stimuli, SSI had better performance than heart rate, BP, or response entropy.

Diagnostic accuracy of bedside ultrasonography in the ICU: feasibility of detecting pulmonary effusion and lung contusion in patients on respiratory support after severe blunt thoracic trauma.

Abstract: Background: Blunt thoracic trauma is a major concern in critically ill patients. Repeated lung diagnostic evaluations are needed in order to follow up the clinical situation and the results of the therapeutic strategies. The aim of this prospective clinical study was to evaluate the possible role of lung ultrasound (LU) compared with bedside radiography (CXR) and computed tomography (CT) used as the gold standard in the evaluation of trauma patients admitted to the intensive care unit with acute respiratory failure. Method: A total of 15 thoracic trauma patients were studied at intensive care unit (ICU) arrival (T1) and 48 h later (T2) with CT, CXR and LU. We evaluated the presence of pleural effusion (PE) and lung contusion (LC). For this purpose the lung parenchyma was divided into 12 regions so that we could compare 180 lung regions at T1 and T2, respectively. Results: Sensitivity of ultrasound was 0.94 for PE and 0.86 for LC while specificity 0.99 and 0.97, respectively. The likelihood ratio was 94 (ρ+) and 0.06 (ρ−) for PE and 28.6 (ρ+) and 0.14 (ρ−) for LC. Conclusions: Ultrasound provides a reliable noninvasive, bedside method for the assessment of chest trauma patients with acute respiratory failure in the ICU.

Chronic pain after hysterectomy

Abstract: Background: Chronic pain is a well-known adverse effect of surgery, but the risk of chronic pain after gynaecological surgery is less established. Method: This review summarizes studies on chronic pain following hysterectomy. The underlying mechanisms and risk factors for the development of chronic post-hysterectomy pain are discussed. Results and conclusion: Chronic pain is reported by 5–32% of women after hysterectomy. A guideline is proposed for future prospective studies.

Lactobacillus plantarum 299v reduces colonisation of Clostridium difficile in critically ill patients treated with antibiotics.

Abstract: Background: The incidence of Clostridium difficile-associated disease (CDAD) in hospitalised patients is increasing. Critically ill patients are often treated with antibiotics and are at a high risk of developing CDAD. Lactobacillus plantarum 299v (Lp299v) has been found to reduce recurrence of CDAD. We investigated intensive care unit (ICU) patients with respect to the impact of Lp299v on C. difficile colonisation and on gut permeability and parameters of inflammation and infection in that context. Methods: Twenty-two ICU patients were given a fermented oatmeal gruel containing Lp299v, and 22 received an equivalent product without the bacteria. Faecal samples for analyses of C. difficile and Lp299v were taken at inclusion and then twice a week during the ICU stay. Other cultures were performed on clinical indication. Infection and inflammation parameters were analysed daily. Gut permeability was assessed using a sugar probe technique. Results: Colonisation with C. difficile was detected in 19% (4/21) of controls but in none of the Lp299v-treated patients (P<0.05). Conclusions: Enteral administration of the probiotic bacterium Lp299v to critically ill patients treated with antibiotics reduced colonisation with C. difficile.

Fast-track surgery for bariatric laparoscopic gastric bypass with focus on anaesthesia and peri-operative care. Experience with 500 cases.

Abstract: Background: Bariatric surgery for morbid obesity implies challenges in anaesthesiological handling. We report our experience from 500 consecutive patients during 3 years. Methods: The patients were due for laparoscopic Roux–en–Y gastric bypass and enteral bypass. Sleep was induced after pre-oxygenation with target control infusions (TCI) of remifentanil and propofol; vecuronium was supplied for facilitating endotracheal intubation. The propofol infusion was stopped and desflurane 3–6% was given for BIS-titrated anaesthetic maintenance together with remifentanil TCI. Antiemetic prophylaxis was supplied with intravenous (IV) droperidol, ondansetron and dexamethasone; post-operative pain prophylaxis was IV paracetamol, parecoxib and bupivacaine infiltration. The patients were extubated in the operating room and kept in the post-operative care unit for 3–4 h, being tested for a 20 m walk before discharge to the ward. Results: The procedure was uncomplicated peri-operatively in all 500 cases and in 497 patients (99.4%) post-operatively. Three patients had one complication, which resolved without sequelae: oesophageal rupture from gastric tubing, reoperation for anastomosis leakage and pneumonia. The mean duration of surgery was 57 min (range 37–91). The mean time from the start of anaesthesia until the start of surgery and time from the end of surgery until the end of anaesthesia were both significantly reduced throughout the study period, from 23 to 7.8 and 5.8 to 1.9 min, respectively (P<0.001). The mean total hospital stay was reduced from 3 days at start to 2 days in the end of the series (P<0.05). Conclusion: Safe bariatric short-stay surgery is feasible with a dedicated anaesthesiological concept in an expert surgical team.

Standard basic life support vs. continuous chest compressions only in out‐of‐hospital cardiac arrest

Abstract: Background The importance of ventilations after cardiac arrest has been much debated recently and eliminating mouth-to-mouth ventilations for bystanders has been suggested as a means to increase bystander cardiopulmonary resuscitation (CPR). Standard basic life support (S-BLS) is not documented to be superior to continuous chest compressions (CCC). Methods Retrospective, observational study of all non-traumatic cardiac arrest patients older than 18 years between May 2003 and December 2006 treated by the community-run emergency medical service (EMS) in Oslo. Outcome for patients receiving S-BLS was compared with patients receiving CCC. All Utstein characteristics were registered for both patient groups as well as for patients not receiving any bystander CPR by reviewing Ambulance run sheets, Utstein forms and hospital records. Method of bystander CPR as well as dispatcher instruction was registered by first-arriving ambulance personnel. Results Six-hundred ninety-five out of 809 cardiac arrests in our EMS were included in this study. Two-hundred eighty-one (40%) received S-CPR and 145 (21%) received CCC. There were no differences in outcome between the two patient groups, with 35 (13%) discharged with a favourable outcome for the S-BLS group and 15 (10%) in the CCC group (P=0.859). Similarly, there was no difference in survival subgroup analysis of patients presenting with initial ventricular fibrillation/ventricular tachycardia after witnessed arrest, with 32 (29%) and 10 (28%) patients discharged from hospital in the S-BLS and CCC groups, respectively (P=0.972). Conclusions Patients receiving CCC from bystanders did not have a worse outcome than patients receiving standard CPR, even with a tendency towards a higher distribution of known negative predictive features.

Anaesthesia and post-operative morbidity after elective groin hernia repair : a nation-wide study

Abstract: Background: Randomised studies suggest regional anaesthesia to have the highest morbidity and local infiltration anaesthesia to have the lowest morbidity after groin hernia repair. However, implications and results of this evidence for general practice are not known. Methods: Prospective nation-wide data collection in a cohort of n=29,033 elective groin hernia repairs, registered in the Danish Hernia Database in three periods, namely July 1998–June 1999, July 2000–June 2001 and July 2002–June 2003. Retrospective analysis of complications in discharge abstracts, identified from re-admission within 30 days post-operatively, prolonged length of stay (>2 days post-operatively) or death. Results: Complications after groin hernia repair were more frequent in patients 65+ years (4.5%), compared with younger patients (2.7%) (P<0.001). In patients 65+ years, medical complications were more frequent after regional anaesthesia (1.17%), compared with general anaesthesia (0.59%) (P=0.003) and urological complications were more frequent after regional anaesthesia (0.87%), compared with local infiltration anaesthesia (0.09%) (P=0.006). Seventeen prostatectomies occurred after post-operative urinary retention, but with no case after local anaesthesia. Mortality within 30 days after elective groin hernia repair was 0.12%. Regional anaesthesia was disproportionately more often used in patients dying within 1 week post-operatively. Conclusion: Choice of the anaesthetic technique should be adjusted to available procedure-specific scientific evidence and the use of regional anaesthesia in elderly patients undergoing groin hernia repair is not supported by existing evidence.

Addition of ketamine to propofol for initiation of procedural anesthesia in children reduces propofol consumption and preserves hemodynamic stability

Abstract: Background: There is no ideal anesthesia protocol to perform short invasive procedures in pediatric oncology. The combination of propofol and ketamine may offer advantages over propofol alone. Methods: In a prospective, randomized, double-blind study, we analyzed 63 consecutive procedures performed in 47 oncology children. All patients received 1 μg/kg fentanyl, followed by propofol 1 mg/kg in group P (n=33) or propofol 0.5 mg/kg and ketamine 0.5 mg/kg in group PK (n=30) for the initiation of anesthesia. The need for supplementation with propofol and/or fentanyl to maintain an adequate level of anesthesia was recorded. The hemodynamic and respiratory profile, recovery time and the occurrence of side effects were compared. Results: Significantly more children required propofol (100% vs. 83.3%) and fentanyl (75.5% vs. 43.3%) rescue doses, and developed hypotension (63.6% vs. 23.4%) and bradycardia (48.5 vs. 23.4%) in group P compared with group PK, with a comparable incidence of respiratory adverse events and recovery times. However, 40% of children in group PK were agitated following recovery compared with 6% in group P. Conclusions: The combination of propofol and ketamine for invasive procedures in pediatric oncology resulted in reduced propofol and fentanyl consumption and preserved hemodynamic stability, but more children in the combination group recovered with agitation.

Children in day surgery: clinical practice and routines. The results from a nation-wide survey.

Abstract: Background: Day surgery is common in paediatric surgical practice. Safe routines including parental and child information in order to optimise care and reduce anxiety are important. Most day surgery units are not specialised in paediatric care, which is why specific paediatric expertise is often lacking. Methods: We studied the practice of paediatric day surgery in Sweden by a questionnaire survey sent to all hospitals, obtaining an 88% response rate. Three specific paediatric cases were enquired for in more detail. Results: The proportion of paediatric day surgery vs. in-hospital procedures was 46%. Seventy-one out of 88 responding units performed paediatric day surgery. All units had anxiolytic pre-medication as a routine in 1-6-year-olds, and in 7-16-year-olds at 60% of the units. Most units performed circumcision and adenoidectomy, while 33% performed tonsillectomy. Anaesthesia induction was intravenous in older children, and also in 1-6-year-olds at 50% of the units. Parental presence at induction was mandatory. Post-operatively, 93% of units routinely assessed pain. Paracetamol and NSAIDs were the most common analgesics, as monotherapy or combined with rescue medication in the recovery as IV morphine. At 42% of units, take-home bags of analgesics were provided, covering 1-3 days of treatment. Pain was the most frequent complaint on follow-up. Micturition difficulties were common after circumcision, nausea after adenoidectomy and nutrition difficulties after tonsillectomy. Conclusions: In Sweden, most day surgery units perform paediatric surgery, most children receive pre-medication, anaesthesia is induced IV and take-home analgesics paracetamol and or NSAIDs are often provided. Still, pain is a common complaint after discharge.

Physiological effects of a lung-recruiting strategy applied during one-lung ventilation.

Abstract: BACKGROUND One-lung ventilation (OLV) affects respiratory mechanics and ventilation/perfusion matching, reducing functional residual capacity of the ventilated lung. While the application of a lung-recruiting manoeuvre (RM) on the ventilated lung has been shown to improve oxygenation, data regarding the impact of RM on respiratory mechanics are not available. METHODS Thirteen patients undergoing lung resection in lateral decubitus were studied. During OLV, a lung-recruiting strategy consisting in a RM lasting 1 min followed by the application of positive end-expiratory pressure 5 cmH(2)O was applied to the ventilated lung. Haemodynamics, gas exchange and respiratory mechanics parameters were recorded on two-lung ventilation (TLV(baseline)), OLV before and 20 min after the RM (OLV(pre-RM), OLV(post-RM), respectively) and TLV(end). Haemodynamics parameters were also recorded during the RM. RESULTS The PaO(2)/FiO(2) ratio was 358+/-126 on TLV(baseline); it decreased to 235+/-113 on OLV(pre-RM) (P<0.01) increased to 351+/-120 on OLV(post-RM) (P<0.01 vs. OLV(pre-RM)), and remain stable thereafter. During the RM, CI decreased from 3.04+/-0.7 l/m(2) OLV(pre-RM) to 2.4+/-0.6 l/m(2) (P<0.05), and returned to baseline on OLV(post-RM) (3.1+/-0.7 l/m(2), NS vs. OLV(pre-RM)). The RM resulted in alveolar recruitment and caused a significant decrease in static elastance of the dependent lung (16.6+/-8.9 cmH(2)O/ml OLV(post-RM) vs. 22.3+/-8.1 cmH(2)O/ml OLV(pre-RM)) (P<0.01). CONCLUSIONS During OLV in lateral decubitus for thoracic surgery, application to the dependent lung a recruiting strategy significantly recruits the dependent lung, improving arterial oxygenation and respiratory mechanics until the end of surgery. However, the transient haemodynamic derangement occurring during the RM should be taken into account.

Remifentanil and the brain.

Abstract: Background and aim: Remifentanil is an ultra-short-acting opioid, increasingly used today in neuroanesthesia and neurointensive care. Its characteristics make remifentanil a potentially ideal agent, but previous data have cast a shadow on this opioid, supporting potentially toxic effects on the ischemic brain. The aim of the present concise review is to survey available up-to-date information on the effects of remifentanil on the central nervous system. Method: A MEDLINE search within the past seven years for available up-to-date information on remifentanil and brain was performed. Results: Concise up-to-date information on the effects of remifentanil on the central nervous system was reported, with a particular emphasis on the following topics: cerebral metabolism, electroencephalogram, electrocorticography, motor-evoked potentials, regional cerebral blood flow, cerebral blood flow velocity, arterial hypotension and hypertension, intracranial pressure, cerebral perfusion pressure, cerebral autoregulation, cerebrovascular CO2 reactivity, cerebrospinal fluid, painful stimulation, analgesia and hyperalgesia, neuroprotection, neurotoxicity and hypothermia. Conclusion: The knowledge of the influence of remifentanil on brain functions is crucial before routine use in neuroanesthesia to improve anesthesia performance and patient safety as well as outcome.

Systematic follow-up increases incidence of anaphylaxis during adverse reactions in anesthetized patients.

Abstract: Background: The incidence of hypersensitivity reactions during anesthesia is underestimated because clinical symptoms may vary and diagnosis is not obvious. Our aim was to investigate the consequences of a systematic follow-up of patients on the estimated incidence of allergic reactions during anesthesia. Methods: We conducted a prospective study over a 2-year period (70,000 anesthesias). When patients were suspected with hypersensitivity reactions or with unexplained adverse reactions during anesthesia, blood was sampled to measure histamine and tryptase, and then skin tests were performed 4–6 weeks later. Results: During the studied period, 39 patients were enrolled in the database. Eight were excluded because of lack of skin tests. Twenty-two patients had clinical features compatible with immediate hypersensitivity reaction, and nine had reactions rated as ‘unexplained’ by the attending physician. Following systematic investigation, we found 22 hypersensitivity reactions (15 patients with obvious and seven with unexplained reactions) during anesthesia. This increases the estimated incidence of hypersensitivity reactions from 1 : 4667 to 1 : 3180 anesthesias. Tryptase concentrations were increased in only 50% of these patients. In our series, positive and negative predictive values of tryptase at T0 for the diagnosis of anaphylaxis were 100% and 60%, respectively. Latex was the major causative agent, followed by neuromuscular blocking agents and antibiotics. Conclusions: Systematic follow-up of patients with unexplained reactions during anesthesia increases the estimated incidence of IgE-mediated hypersensitivity reactions during anesthesia by 50%.

Prediction of post‐operative pain after a laparoscopic tubal ligation procedure

Abstract: Background: Pre-operative identification of reliable predictors of post-operative pain may lead to improved pain management strategies. We investigated the correlation between pre-operative pain, psychometric variables, response to heat stimuli and post-operative pain following a laparoscopic tubal ligation procedure. Methods: Assessments of anxiety, mood, psychological vulnerability and pre-operative pain were made before surgery using the State-Trait Anxiety Inventory (STAI), the Hospital Anxiety Depression Scale (HADS), a psychological vulnerability test and the Short-Form McGill Pain Questionnaire (SF-MPQ), respectively. Pre-operative assessments of thermal thresholds and pain response to randomized series of heat stimuli (1 s, 44-48 degrees C) were made with quantitative sensory testing technique. Post-operative pain intensity was evaluated daily by a visual analogue scale during rest and during standardized dynamic conditions for 10 days following surgery. Univariate and multivariate regression analyses were used to construct prediction models. Results: Fifty-nine patients completed the study. Post-operative pain was significantly correlated with pre-operative pain (SF-MPQ), heat pain perception, psychological vulnerability, STAI and HADS. In the multiple regression model pre-operative pain and heat pain perception were significant predictive factors (R=0.537-0.609). Conclusion: The study indicates that pre-surgical pain and heat pain sensitivity are important pre-operative indicators of post-operative pain intensity, while psychological factors like vulnerability and anxiety seem to contribute to a lesser degree after laparoscopic tubal ligation. The prediction model accounted for 29-43% of the total variance in post-operative movement-related pain. (Less)

Effect of magnesium sulfate on extubation time and acute pain in coronary artery bypass surgery.

Abstract: Background: Post-operative pain control is one of the greatest concerns for both physicians and patients. In this study, the effect of magnesium sulfate (MgSO4) solution infusion on post-operative pain scores and extubation time in patients undergoing elective coronary artery bypass graft (CABG) surgeries was assessed. Methods: In a double-blind, randomized, placebo-controlled clinical trial, 218 patients scheduled for elective CABG were selected and randomly assigned to two groups. After matching inclusion and exclusion criteria for the patients, intravenous MgSO4 was administered intraoperatively for one group and placebo to the second group. Except for this, all the cases were similar regarding anesthesia and surgery. Results: The MgSO4 patients were extubated sooner compared with the placebo group. Pain scores reported by the group who received MgSO4 were less at the 6th, 12th, 18th and 24th hours after the operation; also, they needed less morphine sulfate during this period. Conclusion: The results demonstrated a significantly shortened post-operative time for extubation and reduced acute post-operative pain scores by intravenous MgSO4 infusion during elective CABG surgery.

Effect of Intraoperative Magnesium Sulphate Infusion on Pain Relief After Laparoscopic Cholecystectomy

Abstract: Introduction: The aim of the study is to evaluate the analgesic efficiency of perioperative magnesium sulphate infusion in patients undergoing laparoscopic cholecystectomy (LC) Methods: In a randomized, double-blind trial study, 83 patients were divided into two groups Group MT received 50 mg/kg iv magnesium sulphate in 100 ml of 09% normal saline and Group T received the same volume of isotonic saline during the intraoperative period The cumulative post-operative tramadol consumption was measured to assess the analgesic effect using a patient-controlled analgesia device Pain intensities at rest and while coughing were evaluated at 0, 2, 4, 8, 12, and 24 h post-operatively Results: The pain scores in Group MT were significantly lower than Group T at 0, 4, and 12 h post-operatively The average of visual analogue scale at rest and during cough during 24 h post-operatively was found to be statistically significant between groups The total dose of tramadol the 24-h period in Group MT and Group T was found to be 28134±9082 and 31746±12959, respectively Conclusion: Per-operative 50 mg/kg magnesium sulphate infusion is effective in reducing post-operative pain in patients undergoing LC

Comparison of nerve stimulation vs. ultrasound-guided lateral sagittal infraclavicular block.

Abstract: Background: A nerve stimulation-guided lateral sagittal infraclavicular block (LSIB) has been proven to be an effective block. The purpose of this study was to evaluate whether the use of ultrasound (US) guidance would further improve the block quality of LSIB. Methods: In a prospective manner, 80 adult patients scheduled for hand, wrist and forearm surgery were randomly allocated to US or nerve stimulation (NS) groups. A needle was inserted into a sagittal plane, 20° dorsally, until muscle twitches were observed in synchrony with the stimulation. In the US group, the block was performed using the same puncture site but under ultrasonic guidance. The final position of the needle was verified with the use of a nerve stimulator. A local anesthetic mixture of 20 ml of levobupivacaine, 5 mg/ml and 20 ml of lidocaine and 20 mg/ml with 5 μg/ml epinephrine (total 40 ml) was administered in both groups. Results: The block was successful in 37 patients in the NS group and 38 patients in the US group. Block efficacy was better in the US group than the group NS in radial nerve distribution at 20 min (P<0.05). In the US group, there was a slight tendency toward better block density in other nerve areas also but these differences were not significant. Vascular puncture was noted in three patients in the NS group and none in the US group. Conclusions: The block success rate was high and comparable in both groups. There was a trend toward improved block quality in the US group, although not significant.