A Practical Dosing Algorithm for Deep Neuromuscular Blockade During Total Intravenous Anesthesia: ROCURITHM.

BACKGROUND: The number of trials investigating the effects of deep neuromuscular blockade (NMB) on surgical conditions and patient outcomes is steadily increasing. Consensus on which surgical procedures benefit from deep NMB (a post tetanic count of 1-2) and how to implement it has not been reached. The ESAIC does not advise routine application but recommends use of deep NMB to improve surgical conditions on indication. This study investigates the optimal dosing strategy to reach and maintain adequate deep NMB during total intravenous anesthesia. METHODS: Data from three trials investigating deep NMB during laparoscopic surgery with TIVA (n=424) was pooled to analyze the required rocuronium dose, when to start continuous infusion and how to adjust. The resulting algorithm was validated (n=32) and compared to the success rate in ongoing studies where the algorithm was not used (n=180). RESULTS: The mean rocuronium dose based on actual bodyweight for PTC 1-2 was 1.0 ± 0.27 mg.kg -1.h -1 in the trials where mean duration of surgery was ±2 hours (116 minutes). An induction dose of 0.6 mg.kg -1 lead to a PTC of 1-5 in a quarter of patients after a mean of 11 minutes. The remaining patients were equally divided over too shallow (additional bolus and direct start of continuous infusion) or too deep; a ±15-minute wait after PTC 0 for return of PTC to ≥1. Using the proposed algorithm, a mean 76% of all 5-minute measurements throughout surgery were on target PTC 1-2 in the validation cohort. The algorithm performed significantly better than anesthesiology residents without the algorithm, even after a learning curve from 0-20 patients (42% on target, P≤.001, Cohen's d=1.4 [95% CI 0.9, 1.8]) to 81-100 patients (61% on target, P≤.05, Cohen's d=0.7 [95% CI 0.1, 1.2]). CONCLUSIONS: We propose a dosing algorithm for deep NMB with rocuronium in patients receiving TIVA.

Machine learning based analysis and detection of trend outliers for electromyographic neuromuscular monitoring.

PURPOSE: Neuromuscular monitoring is frequently plagued by artefacts, which along with the frequent unawareness of the principles of this subtype of monitoring by many clinicians, tends to lead to a cynical attitute by clinicians towards these monitors. As such, the present study aims to derive a feature set and evaluate its discriminative performance for the purpose of Train-of-Four Ratio (TOF-R) outlier analysis during continuous intraoperative EMG-based neuromuscular monitoring. METHODS: Patient data was sourced from two devices: (1) Datex-Ohmeda Electromyography (EMG) E-NMT: a dataset derived from a prospective observational trial including 136 patients (21,891 TOF-R observations), further subdivided in two based on the type of features included; and (2) TetraGraph: a clinical case repository dataset of 388 patients (97,838 TOF-R observations). The two datasets were combined to create a synthetic set, which included shared features across the two. This process led to the training of four distinct models. RESULTS: The models showed an adequate bias/variance balance, suggesting no overfitting or underfitting. Models 1 and 2 consistently outperformed the others, with the former achieving an F1 score of 0.41 (0.31, 0.50) and an average precision score (95% CI) of 0.48 (0.35, 0.60). A random forest model analysis indicated that engineered TOF-R features were proportionally more influential in model performance than basic features. CONCLUSIONS: Engineered TOF-R trend features and the resulting Cost-Sensitive Logistic Regression (CSLR) models provide useful insights and serve as a potential first step towards the automated removal of outliers for neuromuscular monitoring devices. TRIAL REGISTRATION: NCT04518761 (clinicaltrials.gov), registered on 19 August 2020.

Good clinical research practice (GCRP) in pharmacodynamic studies of neuromuscular blocking agents III: The 2023 Geneva revision.

The set of guidelines for good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents was developed following an international consensus conference in Copenhagen in 1996 (Viby-Mogensen et al., Acta Anaesthesiol Scand 1996, 40, 59-74); the guidelines were later revised and updated following the second consensus conference in Stockholm in 2005 (Fuchs-Buder et al., Acta Anaesthesiol Scand 2007, 51, 789-808). In view of new devices and further development of monitoring technologies that emerged since then, (e.g., electromyography, three-dimensional acceleromyography, kinemyography) as well as novel compounds (e.g., sugammadex) a review and update of these recommendations became necessary. The intent of these revised guidelines is to continue to help clinical researchers to conduct high-quality work and advance the field by enhancing the standards, consistency, and comparability of clinical studies. There is growing awareness of the importance of consensus-based reporting standards in clinical trials and observational studies. Such global initiatives are necessary in order to minimize heterogeneous and inadequate data reporting and to improve clarity and comparability between different studies and study cohorts. Variations in definitions of endpoints or outcome variables can introduce confusion and difficulties in interpretation of data, but more importantly, it may preclude building of an adequate body of evidence to achieve reliable conclusions and recommendations. Clinical research in neuromuscular pharmacology and physiology is no exception.

Peri-operative management of neuromuscular blockade: A guideline from the European Society of Anaesthesiology and Intensive Care.

Recent data indicated a high incidence of inappropriate management of neuromuscular block, with a high rate of residual paralysis and relaxant-associated postoperative complications. These data are alarming in that the available neuromuscular monitoring, as well as myorelaxants and their antagonists basically allow well tolerated management of neuromuscular blockade. In this first European Society of Anaesthesiology and Intensive Care (ESAIC) guideline on peri-operative management of neuromuscular block, we aim to present aggregated and evidence-based recommendations to assist clinicians provide best medical care and ensure patient safety. We identified three main clinical questions: Are myorelaxants necessary to facilitate tracheal intubation in adults? Does the intensity of neuromuscular blockade influence a patient's outcome in abdominal surgery? What are the strategies for the diagnosis and treatment of residual paralysis? On the basis of this, PICO (patient, intervention, comparator, outcome) questions were derived that guided a structured literature search. A stepwise approach was used to reduce the number of trials of the initial research ( n  = 24 000) to the finally relevant clinical studies ( n  = 88). GRADE methodology (Grading of Recommendations, Assessment, Development and Evaluation) was used for formulating the recommendations based on the findings of the included studies in conjunction with their methodological quality. A two-step Delphi process was used to determine the agreement of the panel members with the recommendations: R1 We recommend using a muscle relaxant to facilitate tracheal intubation (1A). R2 We recommend the use of muscle relaxants to reduce pharyngeal and/or laryngeal injury following endotracheal intubation (1C). R3 We recommend the use of a fast-acting muscle relaxant for rapid sequence induction intubation (RSII) such as succinylcholine 1 mg kg -1 or rocuronium 0.9 to 1.2 mg kg -1 (1B). R4 We recommend deepening neuromuscular blockade if surgical conditions need to be improved (1B). R5 There is insufficient evidence to recommend deep neuromuscular blockade in general to reduce postoperative pain or decrease the incidence of peri-operative complications. (2C). R6 We recommend the use of ulnar nerve stimulation and quantitative neuromuscular monitoring at the adductor pollicis muscle to exclude residual paralysis (1B). R7 We recommend using sugammadex to antagonise deep, moderate and shallow neuromuscular blockade induced by aminosteroidal agents (rocuronium, vecuronium) (1A). R8 We recommend advanced spontaneous recovery (i.e. TOF ratio >0.2) before starting neostigmine-based reversal and to continue quantitative monitoring of neuromuscular blockade until a TOF ratio of more than 0.9 has been attained. (1C).

A survey on the availability, usage and perception of neuromuscular monitors in Europe.

PURPOSE: Neuromuscular blocking agents (NMBAs) are routinely administered to patients in a multiplicity of anesthetic settings. Absence of postoperative residual neuromuscular block is widely considered an anesthetic patient safety mandate. Despite the increasing availability of a wider range of commercial quantitative neuromuscular monitors, the availability and use of neuromuscular monitoring devices is deemed to be suboptimal even in countries with above-average health system ratings. The present study aims to more precisely characterize the perceived availability, cost sensitivity and usability of neuromuscular monitoring devices within European anesthesia departments. METHODS: A pre-registered internet-based survey assessing the availability, cost sensitivity and usability of neuromuscular monitoring devices was distributed as e-mail newsletter by the European Society of Anaesthesiology and Intensive Care (ESAIC) to all of its active full members. The survey was available online for a total of 120 days. RESULTS: Having targeted a total of 7472 ESAIC members, the survey was completed by a total of 692 anesthesiologists (9.3%) distributed across 37 different European countries. Quantitative monitors were reported to be proportionally more available than qualitative ones (87.6% vs. 62.6%, respectively), as well as in greater monitor-per-operating room ratios. Most anesthesiologists (60.5%) expressed moderate confidence in quantitative monitors, with artifactual recordings and inaccurate measurements being the most frequently encountered issues (25.9%). The commercial pricing of quantitative devices was considered more representative of a device's true value, when compared to qualitative instruments (average cost of €4.500 and €1.000 per device, respectively). CONCLUSION: The availability of quantitative NMM in European operating theaters has increased in comparison with that reported in previous decades, potentially indicating increasing monitoring rates. European anesthesiologists express moderate confidence in quantitative neuromuscular monitors, along with a sentiment of adequate pricing when compared to their qualitative counterparts. Trust in quantitative monitors is marked by caution and awareness for artifactual recordings, with a consequent expectation that developments focusing on accuracy, reliability and ergonomics of neuromuscular monitors be prioritized.

Medical disease and ambulatory surgery, new insights in patient selection based on medical disease.

PURPOSE OF REVIEW: Improvements in perioperative care contributed to enlarge the eligibility criteria for day case surgery and more and more patients with comorbidities may be concerned. However, underlying medical diseases may influence postoperative outcomes, and therefore, must be considered when selecting patients to undergo ambulatory surgery. RECENT FINDINGS: To limit postoperative complications, rigid patient selection criteria are often applied in ambulatory surgery. In practice, however, most of these criteria predict the occurrence of treatable perioperative adverse events but not the need for unanticipated admission or readmission. SUMMARY: The underlying medical diseases should not be considered as sole criteria but they should rather be regarded as a dynamic process, which includes the surgical procedure as well as the experience and expertise of the perioperative setting.

Impact of rocuronium on intraoperative neuromonitoring vagal amplitudes during thyroidectomy.

PURPOSE: Neuromuscular blocking agents (NMBA) facilitate endotracheal intubation and reduce related laryngeal morbidity. However, NMBA interfere with intraoperative neuromonitoring amplitudes during thyroidectomy. The goal of this study was to evaluate the impact of rocuronium used for tracheal intubation on early intraoperative neuromonitoring vagal amplitudes observed during first thyroid lobe dissection. METHODS: This is an observational pharmacoepidemiological study with prospective data collection and retrospective analysis. During the study period, all consecutive patients who underwent thyroid surgery with neuromonitoring were included. Patients underwent endotracheal intubation either using a single dose of rocuronium (NMBA group) or without NMBA (NMBA-free group) according to the anesthesiologist's preference. RESULTS: Six hundred six patients were included (213 NMBA and 393 NMBA-free group patients). At V1, 39 patients (18%) in the NMBA group had an amplitude < 100 µV (need for curarization reversal in 30 patients) and 13 patients (3.3%) in the NMBA-free group (p < 0.001). In the remaining 554 patients, the mean V1 amplitude was significantly decreased in the NMBA group (544 versus 685 µV; p < 0.001). After exclusion of 25 patients with loss of signal types 1 and 2 during dissection, the difference between mean V1 and mean V2 was significantly lower in NMBA group patients (- 22 versus - 86 µV; p = 0.016). CONCLUSION: This study provides new data showing how NMBA used for tracheal intubation significantly decrease V1 amplitude baseline and modify amplitude variations from V1 to V2 values during the first thyroid lobe dissection. LEVEL OF EVIDENCE: Pharmacoepidemiological study.

Neuromuscular block in patients 80 years and older: a prospective, controlled study.

BACKGROUND: An increasing number of patients older than 80 years are undergoing anesthesia, but little information is available regarding pharmacodynamic effects of myorelaxants in this population. This study aims to compare the time course of rocuronium neuromuscular block in patients ≥ 80 years with those of younger adults. METHODS: Under total intravenous anesthesia with propofol and sufentanil, time course of a bolus of rocuronium 0.6 mg/kg neuromuscular block was assessed with acceleromyography in patients ≥ 80 and in patients 20-50 years old. Onset time, clinical duration, duration until 90% and 100% recovery of baseline were determined. RESULTS: Data from 32 patients were analyzed, 16 were ≥ 80 years and 16 were 20-50 years old. Demographic data are shown in Table 1. In the group ≥ 80, onset time was 190 s ± 46 s compared to 123 s ± 40 s in the group 20-50, P < 0.001 and the clinical duration was 52 [48-69.5] min and 36 [34-41] min, respectively, P < 0.001. Duration to 90% recovery of baseline was 77.5 [71-88.5] min and duration to 100% recovery of baseline was 91.2 [82.2-98] min in patients ≥ 80 years and the corresponding values in the patients 20-50 years old were 53.5 [49-55.5] min and 59.5 [56.5-70.25] min, respectively, P < 0.001. CONCLUSION: Compared to younger adults rocuronium shifted in patients ≥ 80 years from a rapid onset, intermediate acting compound to a slower onset, long-acting compound. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03551652 (29/05/2018).

A modified train-of-four ratio to assess recovery from depolarizing neuromuscular blockade after succinylcholine, a prospective observational study.

Succinylcholine is still used in clinical practice. Its duration is highly variable and neuromuscular monitoring is recommended to assess its recovery. Unfortunately, depolarizing neuromuscular block cannot be evaluated by train-of-four (TOF) as no fade occurs. Only single twitch (ST) allows to monitor depolarizing block. The TOFScan monitor proposes a modified TOF ratio (T4/Tref) not referring to fade within a TOF series. We hypothesized that the T4/Tref allows to assess recovery from succinylcholine. This observational study aims to compare recovery from depolarizing block simultaneously assessed with T4/Tref and ST. After Ethics Committee approval and written informed consent 45 patients receiving a single dose of succinylcholine were included. ST recovery, measured with TOF-Watch SX, and T4/Tref recovery, measured by TOFScan, were assessed simultaneously. Difference between measurements was compared using Mann-Whitney U test and overall concordance with the intraclass correlation coefficient (ICC). The ICC was 0.85 [95% CI 0.82-0.87]. The first T4/Tref ratio ≥ 90% was 97% [95% CI 93-101%] the corresponding ST value was 91% [95% CI 87-97%]. The first T4/Tref ratio ≥ 100% was 103% [95% CI 102-107%], the corresponding ST value was 104% [95% CI 100-106%]; median [95% confidence interval of the median]. Time to recovery to 90% and 100% of baseline did not differ between ST or T4/Tref. It was10.0 [8.0-13.0] min vs 10.0 [8.0-12.0] min, P = 0.307 and 10.0 [9.0-15.0] min vs 10.0 [8.0-15.0] min, P = 0.546; respectively; median [IQR]. Agreement between both parameters was excellent. The T4/Tref can be used accurately to measure recovery from depolarizing neuromuscular block.

The impact of intra-abdominal pressure on perioperative outcomes in laparoscopic cholecystectomy: a systematic review and network meta-analysis of randomized controlled trials.

BACKGROUND: Laparoscopic cholecystectomy involves using intra-abdominal pressure (IAP) to facilitate adequate surgical conditions. However, there is no consensus on optimal IAP levels to improve surgical outcomes. Therefore, we conducted a systematic literature review (SLR) to examine outcomes of low, standard, and high IAP among adults undergoing laparoscopic cholecystectomy. METHODS: An electronic database search was performed to identify randomized controlled trials (RCTs) that compared outcomes of low, standard, and high IAP among adults undergoing laparoscopic cholecystectomy. A Bayesian network meta-analysis (NMA) was used to conduct pairwise meta-analyses and indirect treatment comparisons of the levels of IAP assessed across trials. RESULTS: The SLR and NMA included 22 studies. Compared with standard IAP, on a scale of 0 (no pain at all) to 10 (worst imaginable pain), low IAP was associated with significantly lower overall pain scores at 24 h (mean difference [MD]: - 0.70; 95% credible interval [CrI]: - 1.26, - 0.13) and reduced risk of shoulder pain 24 h (odds ratio [OR] 0.24; 95% CrI 0.12, 0.48) and 72 h post-surgery (OR 0.22; 95% CrI 0.07, 0.65). Hospital stay was shorter with low IAP (MD: - 0.14 days; 95% CrI - 0.30, - 0.01). High IAP was not associated with a significant difference for these outcomes when compared with standard or low IAP. No significant differences were found between the IAP levels regarding need for conversion to open surgery; post-operative acute bleeding, pain at 72 h, nausea, and vomiting; and duration of surgery. CONCLUSIONS: Our study of published trials indicates that using low, as opposed to standard, IAP during laparoscopic cholecystectomy may reduce patients' post-operative pain, including shoulder pain, and length of hospital stay. Heterogeneity in the pooled estimates and high risk of bias of the included trials suggest the need for high-quality, adequately powered RCTs to confirm these findings.

Ten years of the Helsinki Declaration on patient safety in anaesthesiology: An expert opinion on peri-operative safety aspects.

: Patient safety is an activity to mitigate preventable patient harm that may occur during the delivery of medical care. The European Board of Anaesthesiology (EBA)/European Union of Medical Specialists had previously published safety recommendations on minimal monitoring and postanaesthesia care, but with the growing public and professional interest it was decided to produce a much more encompassing document. The EBA and the European Society of Anaesthesiology (ESA) published a consensus on what needs to be done/achieved for improvement of peri-operative patient safety. During the Euroanaesthesia meeting in Helsinki/Finland in 2010, this vision was presented to anaesthesiologists, patients, industry and others involved in health care as the 'Helsinki Declaration on Patient Safety in Anaesthesiology'. In May/June 2020, ESA and EBA are celebrating the 10th anniversary of the Helsinki Declaration on Patient Safety in Anaesthesiology; a good opportunity to look back and forward evaluating what was achieved in the recent 10 years, and what needs to be done in the upcoming years. The Patient Safety and Quality Committee (PSQC) of ESA invited experts in their fields to contribute, and these experts addressed their topic in different ways; there are classical, narrative reviews, more systematic reviews, political statements, personal opinions and also original data presentation. With this publication we hope to further stimulate implementation of the Helsinki Declaration on Patient Safety in Anaesthesiology, as well as initiating relevant research in the future.

Procedural sedation outside the operating room.

PURPOSE OF REVIEW: The present review provides an overview of the different fields of procedural sedation and analgesia (PSA), describing the evidence from recently published studies concerning anxiety and moderate pain, cardiac interventions, gastrointestinal interventions, and PSA use in infants. It also provides guidance for practitioners of both unscheduled and scheduled procedural sedation, and a summary of the current guideline for PSA. RECENT FINDINGS: Safety always has to be first priority. Recently published literature is focusing on the combination of different well established drugs such as dexmedetomidine, remifentanil, propofol, and ketamine. These traditional and well known drugs are commonly used for PSA. The combinational use of multiple drugs seems to have benefits for both the provider and patient. Furthermore, there is growing interest into specific protocols and adaption for special circumstances. The preferred medications used for PSA should be both effective and well tolerated. SUMMARY: Procedural sedation deserves to have high degree of attention for potential adverse events. New combinations of well established drugs provide a better pharmacokinetic profile, fit to different indications and offer multiple benefits for both provider and patient.

Deep neuromuscular blockade improves surgical conditions during gastric bypass surgery for morbid obesity: A randomised controlled trial.

BACKGROUND: There is a controversy in the literature whether deep compared with moderate neuromuscular block (NMB) improves surgical conditions for laparoscopic surgery. OBJECTIVES: The primary outcome measure was to examine whether switching from moderate to deep NMB improves surgical conditions for laparoscopic surgery in the obese; secondary outcome measures were changes in intra-abdominal pressure, time required to perform the gastrojejunal anastomosis and peri-operative surgical complications. DESIGN: A single-centre, randomised controlled study. Each patient was taken as their own control and examined twice: at the first evaluation (E1), all patients had a moderate NMB, thereafter patients were randomised to deep or moderate block and a second evaluation (E2) was performed within 10 min. Patients with excellent rating at E1 were excluded from E2, as their surgical condition could not be further improved. SETTING: University Hospital France. PATIENTS: Patients undergoing laparoscopic gastric bypass surgery under general anaesthesia were included. Main exclusion criteria were hypersensitivity to the drugs used and absence of written informed consent. INTERVENTIONS: According to the group assignment, patients received bolus doses of rocuronium or 0.9% saline. MAIN OUTCOME MEASURES: Surgical conditions were assessed with a 4-point rating scale. Intra-operative adverse events were assessed with the Kaafarani-classification and postoperative complications with the Clavien-Dindo classification. RESULTS: Eighty-nine patients were initially included and data from 85 could be assessed at E1; surgical rating was excellent in 20, good in 35, acceptable in 18, poor in 12. After excluding those with an excellent rating, the remaining 65 patients were randomly assigned to deep or moderate block. At E2, an improvement of surgical conditions was observed in 29 out of 34 patients with deep block and in four out of 31 with moderate block; P < 0.0001. Poor surgical conditions were more frequently associated with surgical complications (61.5 versus 15.3%; P < 0.001). CONCLUSION: Switching from moderate to deep block improves surgical conditions. Poor surgical conditions were associated with a higher incidence of surgical complications. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02118844.

Neostigmine-based reversal of intermediate acting neuromuscular blocking agents to prevent postoperative residual paralysis: A systematic review.

BACKGROUND: Neostigmine is widely used to antagonise residual paralysis. Over the last decades, the benchmark of acceptable neuromuscular recovery has increased progressively to a train-of-four (TOF) ratio of at least 0.9. Raising this benchmark may impact on the efficacy of neostigmine. OBJECTIVE(S): The systematic review evaluates the efficacy of neostigmine to antagonise neuromuscular block to attain a TOF ratio of at least 0.9. DESIGN: We performed a systematic search of the literature from January 1992 to December 2015. DATA SOURCES OR SETTING: PubMed, EMBASE and the Cochrane Controlled Clinical Trials database were searched for randomised controlled human studies. Search was performed without language restrictions, using the following free text terms: 'neostigmine', 'sugammadex', 'edrophonium' or 'pyridostigmine' AND 'neuromuscular block', 'reversal' or 'reverse'. ELIGIBILITY CRITERIA: Studies were accepted for inclusion if they used quantitative neuromuscular monitoring and neostigmine as the reversal agent. Selected trials were checked by two of the authors for data integrity. Trials relevant for inclusion had to report the number of patients included, the type of anaesthetic maintenance, the type of neuromuscular blocking agent used, the reversal agent and dose used, the depth of neuromuscular block when neostigmine was administered and the reversal time (time from injection of neostigmine until a TOF ratio ≥0.9 was attained). RESULTS: 19 trials were eligible for quantitative analysis. In patients with deep residual block [T1 (first twitch height) <10%] 70 µg kg neostigmine was used (five trials, 118 patients), and the mean reversal time was 17.1 min (95% confidence interval (CI) [12.4 to 21.8]). In patients with moderate residual block (T1 10% to <25%) the mean neostigmine dose was 56 µg kg (seven trials, 342 patients), and the mean reversal time was 11.3 min (95% CI [9.2 to 13.4]). In patients with a shallow residual block (T1 ≥ 25%) the mean neostigmine dose was 40 µg kg (13 trials, 535 patients), and the mean reversal time was 8.0 min (95% CI [6.8 to 9.2]). CONCLUSION: Based on the findings of this systematic review, we recommend that the administration of neostigmine be delayed until an advanced degree of prereversal recovery has occurred (i.e. a T1 >25% of baseline), or that a recovery time longer than 15 min be accepted.

European Society of Anaesthesiology and European Board of Anaesthesiology guidelines for procedural sedation and analgesia in adults.

: Procedural sedation and analgesia (PSA) has become a widespread practice given the increasing demand to relieve anxiety, discomfort and pain during invasive diagnostic and therapeutic procedures. The role of, and credentialing required by, anaesthesiologists and practitioners performing PSA has been debated for years in different guidelines. For this reason, the European Society of Anaesthesiology (ESA) and the European Board of Anaesthesiology have created a taskforce of experts that has been assigned to create an evidence-based guideline and, whenever the evidence was weak, a consensus amongst experts on: the evaluation of adult patients undergoing PSA, the role and competences required for the clinicians to safely perform PSA, the commonly used drugs for PSA, the adverse events that PSA can lead to, the minimum monitoring requirements and post-procedure discharge criteria. A search of the literature from 2003 to 2016 was performed by a professional librarian and the retrieved articles were analysed to allow a critical appraisal according to the Grading of Recommendations Assessment, Development and Evaluation method. The Taskforce selected 2248 articles. Where there was insufficiently clear and concordant evidence on a topic, the Rand Appropriateness Method with three rounds of Delphi voting was used to obtain the highest level of consensus among the taskforce experts.These guidelines contain recommendations on PSA in the adult population. It does not address sedation performed in the ICU or in children and it does not aim to provide a legal statement on how PSA should be performed and by whom. The National Societies of Anaesthesiology and Ministries of Health should use this evidence-based document to help decision-making on how PSA should be performed in their countries. The final draft of the document was available to ESA members via the website for 4 weeks with the facility for them to upload their comments. Comments and suggestions of individual members and national Societies were considered and the guidelines were amended accordingly. The ESA guidelines Committee and ESA board finally approved and ratified it before publication.

Does formalin fixation influence MSCT/CBCT accuracy?

PURPOSE: Advanced imaging modalities, such as multi-slice computed tomography (MSCT) and cone beam computed tomography (CBCT), greatly facilitate diagnostic medicine. In radiological research, it is important to know how accurately a scanned object is visualized, and whether the methodology leads to image distortion. The objective of this study was to evaluate whether formalin fixation impacted the accuracy of virtual 3D bone models generated via CBCT and MSCT using a software-based evaluation method that excluded human measurement errors. METHODS: A head specimen, with and without formalin preservation, was subjected to MSCT and CBCT scans using the manufacturers' predefined scanning protocols. Digital models of the lower jaw were constructed and superimposed with a master model generated based on optical scanning with an industrial non-contact scanner. Means and standard deviations were calculated to assess accuracy, and a t test was used for comparisons between the fixed and unfixed specimens. RESULTS: The extent of discrepancy between the fixed and unfixed specimens was analyzed using a total of 200 points (n = 200) in each specimen state. The mean deviation between states was 0.01 mm for MSCT (at both 80 and 140 kV). Mean values from CBCT at 0.4 voxel did not differ between states. CONCLUSIONS: Our results suggest that formalin fixation of an anatomical specimen does not substantially affect the accuracy of a three-dimensional image generated with CBCT and MSCT. Thus, fixed specimen can be used in future investigations of 3D models without concerns regarding the accuracy.