Anaesthesiology

Improvement in postoperative pain control by combined use of intravenous dexamethasone with intravenous dexmedetomidine after interscalene brachial plexus block for arthroscopic shoulder surgery: A randomised controlled trial BACKGROUND Intravenous dexamethasone or dexmedetomidine is reported to prolong the duration of analgesia after single-shot interscalene brachial plexus block (ISBPB). However, the effect of co-administration of these agents on the duration of analgesia has not been evaluated. OBJECTIVES We evaluated the difference in time to first rescue analgesic request between patients receiving co-administered intravenous dexamethasone and dexmedetomidine and patients receiving intravenous dexamethasone alone after single-shot ISBPB for arthroscopic shoulder surgery. DESIGN A prospective, randomised controlled study. SETTING A single tertiary care centre, study period from August 2017 to January 2018. PATIENTS Sixty-six patients undergoing arthroscopic shoulder surgery with ISBPB with 15 ml of 0.5% ropivacaine with 1 : 200 000 epinephrine. INTERVENTIONS We randomly assigned the patients to one of three groups: intravenous 0.9% saline (control), intravenous dexamethasone 0.11 mg kg−1 (D1 group), or co-administered intravenous dexamethasone 0.11 mg kg−1 and intravenous dexmedetomidine 1.0 μg kg−1 (D2 group). MAIN OUTCOME MEASURES The primary outcome was the time to first rescue analgesic request. RESULTS The median [interquartile range] time to first rescue analgesic request was significantly longer for the D2 group (66.3 h [23.3 to 72]) than the D1 (17.4 h [14.9 to 36], P = 0.002) and control (10.9 h [10.1 to 12.2], P < 0.001) groups. The D1 and D2 groups both had reduced pain scores, reduced postoperative opioid consumption, less sleep disruption and improved patient satisfaction compared with the control group. There were no significant elevations in blood glucose concentrations in patients receiving dexamethasone (D1 and D2 groups) compared with the control group at postoperative day 1. CONCLUSION Co-administration of intravenous dexamethasone (0.11 mg kg−1) with dexmedetomidine (1.0 μg kg−1) significantly prolonged the time to first rescue analgesic request after single-shot ISBPB in patients undergoing arthroscopic shoulder surgery. TRIAL REGISTRATION Clinical Trial Registry of Korea; https://cris.nih.go.kr/cris/index.jsp and identifier: KCT0002569. Correspondence to Justin S. Ko, Department of Anaesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon ro, Gangnam gu, Seoul 06351, South Korea Tel: +82 2 3410 2454; fax: +82 2 3410 0361; e-mail: jsko@skku.edu © 2019 European Society of Anaesthesiology

Is 'anxiety sensitivity' predictive of postoperative nausea and vomiting?: A prospective observational study BACKGROUND Postoperative nausea and vomiting (PONV) is an extremely distressing side effect for patients. Despite PONV prophylaxis guided by well established scoring systems, the incidence of PONV is still high. OBJECTIVE The aim of the current study was to investigate the predictive value of anxiety sensitivity as an additional independent risk factor for PONV in patients with an increased risk of PONV. DESIGN A noninterventional, observational study. SETTING A tertiary care university hospital. PATIENTS Patients with an increased risk of PONV (i.e. female, nonsmoking) undergoing elective surgery (general, gynaecological, urological, musculoskeletal or neurosurgical) under general anaesthesia. MAIN OUTCOME MEASURES The number of patients with anxiety sensitivity assessed pre-operatively with the Anxiety Sensitivity Index-3 questionnaire, the number of patients experiencing PONV, predictive value of anxiety sensitivity compared with other established risk factors for PONV. RESULTS Some 41.5% of the patients experienced PONV within the first 24 h after surgery. In these patients increased anxiety sensitivity (Anxiety Sensitivity Index-3 score higher than seven points) was associated with a five-fold increase in the odds ratio (OR) for PONV. From the regression model, the risk of PONV was increased by lack of PONV prophylaxis (OR, 3.68), the postoperative administration of opioids (OR, 3.60) and patient age (OR, 1.03), but laparoscopic surgery did not increase the risk. CONCLUSION In addition to the well established risk factors, anxiety sensitivity can help to predict the risk of PONV. It seems justifiable to add psychological factors such as anxiety sensitivity to PONV risk-scores. PONV prophylaxis should be considered when anxiety sensitivity is high. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01875120. Correspondence to Rita Laufenberg-Feldmann, MD, Department of Anaesthesiology, University Medical Centre of the Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131 Mainz, Germany Tel: +49 6131 177248/+49 6131 176751; fax: +49 06131 176209; e-mail: rita.laufenberg@unimedizin-mainz.de Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (www.ejanaesthesiology.com). © 2019 European Society of Anaesthesiology

Intra-operative high inspired oxygen fraction does not increase the risk of postoperative respiratory complications: Alternating intervention clinical trial BACKGROUND The WHO recommends routine intra-operative and early postoperative use of high inspired oxygen concentrations (hyperoxia). However, a high intra-operative inspired oxygen fraction (FiO2) might result in an increased risk of postoperative respiratory complications. AIM To test the hypothesis that intra-operative FiO2 of 80% compared with 30% inspired oxygen decreases the postoperative ratio of arterial saturation to fraction of inspired oxygen (SpO2/FiO2). Secondarily, to evaluate whether an intra-operative inspired FiO2 of 80% increases the incidence of pulmonary complications. DESIGN Posthoc subanalysis of a large alternating cohort trial. SETTING Cleveland Clinic, Cleveland, United States, from 2013 to 2016. PATIENTS Adults having colorectal surgery. Cases lasting less than 2 h, re-operations on the same hospitalisation, and cases with missing intra-operative or postoperative data were excluded. INTERVENTION Maintaining intra-operative FiO2 at 30 or 80% and alternating this management every 2 weeks for a study period of 39 months. MAIN OUTCOME Minimal SpO2/FiO2 ratio value in the postanaesthesia care unit. Secondary outcome was a composite of postoperative pulmonary complications throughout hospitalisation. RESULTS A total of 5056 patients were included. Groups were well balanced on all demographic, baseline and procedural variables. Median time-weighted averages of intra-operative FiO2 in the 30 and 80% groups were 43% (IQR 38 to 54%, N=2486) and 81% (IQR 78 to 82%, N=2570), respectively. No difference was found in the lowest SpO2/FiO2 ratio (estimated median difference 0 [95% confidence interval: 0, 0], P = 0.91). The incidence of postoperative pulmonary complications was 16.3 and 17.6% in the 30 and 80% FiO2 groups, respectively (relative risk 1.07 [95% confidence interval: 0.95, 1.21], P = 0.25). CONCLUSION Intra-operative hyperoxia did not change the postoperative SpO2/FiO2 ratio or the risk for pulmonary complications. Clinicians should not refrain from using hyperoxia for fear of provoking respiratory complications. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01777568. Correspondence to Alparslan Turan, MD, Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, 9500 Euclid Ave P77, Cleveland, OH 44195, USA Tel: +1 216 445 9857; fax: +1 216 444 6135; e-mail: Turana@ccf.org Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (www.ejanaesthesiology.com). © 2019 European Society of Anaesthesiology

Metamizole vs. ibuprofen at home after day case surgery: A double-blind randomised controlled noninferiority trial BACKGROUND NSAIDs and paracetamol are the cornerstones of pain treatment after day case surgery. However, NSAIDs have numerous contraindications and consequently are not suitable in up to 25% of patients. Metamizole is a non-opioid compound with a favourable gastro-intestinal and cardiovascular profile compared with NSAIDs. OBJECTIVES The study aimed to assess if a combination of metamizole and paracetamol is noninferior to a combination of ibuprofen and paracetamol in treating pain at home after painful day case surgery. METHODS Two hundred patients undergoing elective ambulatory haemorrhoid surgery, arthroscopic shoulder or knee surgery, or inguinal hernia repair were randomly allocated to receive either metamizole and paracetamol (n=100) or ibuprofen and paracetamol (n=100) orally for 4 days between January 2016 and March 2017 in this double-blind, randomised, controlled, single-centre, noninferiority trial. Average postoperative pain intensity using a numerical rating scale and use of rescue medication were measured in the postanaesthesia care unit (PACU) and on postoperative days (POD) 1 to 3. A difference in mean numerical rating scale score of 1 point or less was considered noninferior. Adverse effects of study medication and satisfaction with study medication were measured on PODs 1 to 3 by telephone follow-up. RESULTS In the PACU, the difference in mean ± SD pain score between metamizole and paracetamol and ibuprofen and paracetamol was 0.85 ± 0.78. From POD 1 to 3, this difference was lower than 1, resulting in noninferiority. Rescue opioid consumption in the PACU and on PODs 1 and 3 was not significantly different between treatment groups. Rescue opioid consumption on POD2 was significantly higher in the ibuprofen and paracetamol group (P = 0.042). Adverse effects of study medication and overall patient satisfaction were similar in both groups. CONCLUSION Paracetamol/metamizole and paracetamol/ibuprofen are equally effective in treatment of acute postoperative pain at home after ambulatory surgery with comparable patient satisfaction levels. TRIAL REGISTRATION European Union Clinical Trials Register 2015-003987-35. Correspondence to Björn Stessel, MD, PhD, Department of Anesthesiology and Pain Medicine, Jessa Hospital, Hasselt, Belgium E-mail: bjornstessel@hotmail.com © 2019 European Society of Anaesthesiology

Recent Advances in Anesthesiology No abstract available

Flow-controlled ventilation during ear, nose and throat surgery: A prospective observational study BACKGROUND Flow-controlled ventilation (FCV) is a new mechanical ventilation mode that maintains constant flow during inspiration and expiration with standard tidal volumes via cuffed narrow-bore endotracheal tubes. Originating in manually operated 'expiratory ventilation assistance', FCV extends this technique by automatic control of airway flow, monitoring of intratracheal pressure and control of peak inspiratory pressure and end-expiratory pressure. FCV has not yet been described in a clinical study. OBJECTIVE The aim of this study was to provide an initial assessment of FCV in mechanically ventilated patients undergoing ear, nose and throat surgery and evaluate its potential for future use. DESIGN An observational study. SETTING Two German academic medical centres from 24 November 2017 to 09 January 2018. PATIENTS Consecutive patients (≥ 18 years) scheduled for elective ear, nose and throat surgery. Exclusion criteria were planned laser surgery, intended fibreoptic awake intubation, emergency procedures, increased risk of aspiration, American Society of Anesthesiologists (ASA) physical status more than III and chronic obstructive pulmonary disease classified as GOLD stage more than II. INTERVENTION Peri-operative use of FCV provided by a new type of ventilator (Evone) via a narrow-bore endotracheal tube (Tritube). MAIN OUTCOME MEASURES Minute volume, respiratory rate, intratidal tracheal pressure amplitude (Δp) and end-tidal CO2 (PetCO2) were recorded every 5 min. All adverse events were noted. Data are presented as median [IQR]. RESULTS Sixteen patients provided 15 evaluable data sets. A minute volume of 5.0 [4.4 to 6.4] l min−1 and a respiratory rate of 9 [8 to 11] min−1 generated a PetCO2 of 4.9 [4.8 to 5.0] kPa. Δp was 10 [9 to 12] cmH2O. Five adverse events were recorded: a tube obstruction due to airway secretions and four tube dislocations (two attributed to coughing, two not study-related). CONCLUSION FCV achieves adequate PetCO2 levels with minute volume and Δp in the normal range. Tritube's high flow resistance may increase the likelihood of tube dislocations if the patient coughs. Although further evaluation is necessary, FCV provides a new option for short-term mechanical ventilation. The successful operation of FCV with narrow-bore tubes contributes to the armamentarium for airway management. TRIAL REGISTRATION DRKS00013312 This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0 Correspondence to Dr. Johannes Schmidt, Department of Anaesthesiology and Critical Care, Medical Centre – University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany Tel: +49 761 270 26390; e-mail: johannes.schmidt@uniklinik-freiburg.de Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (www.ejanaesthesiology.com). © 2019 European Society of Anaesthesiology

Pre-operative assessment of 30-day mortality risk after major surgery: the role of the quick sequential organ failure assessment: A retrospective observational study BACKGROUND The quick Sequential Organ Failure Assessment (qSOFA) is intended for the assessment of the prognosis and risk of sepsis. It may also help predict the mortality risk of nonseptic patients. OBJECTIVE This study investigated the relationship between pre-operative qSOFA scores and 30-day mortality after major surgery. It also evaluated the predictive value of qSOFA scores combined with the American Society of Anesthesiologists (ASA) physical status and Charlson comorbidity index (CCI). DESIGN A retrospective observational study. SETTING Single tertiary academic hospital. PATIENTS Medical records of patients who underwent major surgery (estimated blood loss >500 ml; surgery time >2 h) between January 2010 and December 2017 were examined. MAIN OUTCOME MEASURES The qSOFA score was measured within 24 h before surgery, and its association with 30-day mortality was analysed using multivariable logistic regression. A receiver-operating characteristic curve analysis was used to investigate the predictive power of the pre-operative qSOFA scores combined with the ASA physical status and with CCI. RESULTS A total of 6336 patients were included in the final analysis, and 91 (1.4%) died within 30 days. The multivariable logistic regression analysis including all covariates indicated that 30-day mortality was 2.43-times higher for the score 1 group than for the score 0 group (P = 0.002), and it was 3.54-times higher for the score at least 2 group than for the score 0 group (P < 0.001). The area under the curve (AUC) of the pre-operative qSOFA, ASA physical status and CCI were 0.69, 0.55 and 0.57, respectively. When the pre-operative qSOFA score was combined with the ASA physical status or CCI, the AUCs were 0.73 and 0.72, respectively. CONCLUSION Higher pre-operative qSOFA scores within 24 h of surgery were associated with increased 30-day mortality. Pre-operative qSOFA scores have better predictive value for 30-day mortality when combined with the ASA physical status or CCI. Correspondence to Tak Kyu Oh, MD, Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Gumi-ro 173 Beon-gil, Bundang-gu, Seongnam 13620, Korea Tel: +82 31 787 7499; fax: +82 31 787 4063; e-mail: airohtak@hotmail.com Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (www.ejanaesthesiology.com). © 2019 European Society of Anaesthesiology

Pediatric Anesthesia: A Problem-Based Learning Approach No abstract available

Comparison of pre-oxygenation using spontaneous breathing through face mask and high-flow nasal oxygen: A prospective randomised crossover controlled study in healthy volunteers BACKGROUND High-flow nasal oxygen (HFNO) therapy has been proposed for pre-oxygenation before intubation, but the end-tidal fraction of oxygen (ETO2) obtained remains unknown. OBJECTIVE(S) To compare the ETO2 following a 3 min pre-oxygenation with HFNO and face mask. SETTING Operating room in a primary university hospital. DESIGN A prospective, randomised crossover study. PARTICIPANTS Fifty healthy volunteers. INTERVENTIONS Participants were randomly pre-oxygenated through spontaneous breathing 100% oxygen in a face mask and with HFNO (mouth closed, heated and humidified gas flow at 60 l min–1). In the face mask group, the ETO2 was measured continuously. In the HFNO group, the nasal cannula was quickly exchanged with a face mask while the subject held their breath at end inspiration and the ETO2 was measured after a deep expiration. The protocol ended when ETO2 reached 90% or otherwise at 6 min. MAIN OUTCOME MEASURES The primary endpoint was the ETO2 after 3 min of pre-oxygenation. Secondary endpoints were the proportion of participants with an ETO2 at least 90% and the time until the ETO2 at least 90%. RESULTS The ETO2 after 3 min of pre-oxygenation was 89 (2) % and 77 (12) % in the face mask and HFNO groups [difference 12% (95% confidence interval, 95% CI: 8 to 15]; P < 0.001), respectively. After 3 min of pre-oxygenation, 54 and 4% (P < 0.001) of volunteers had an ETO2 at least 90% in the face-mask and HFNO groups, respectively. After 6 min of pre-oxygenation, 96 and 46% (P < 0.001) of volunteers had an ETO2 at least 90% in the face-mask and HFNO groups, respectively. In the face mask group, the hazard ratio to achieve an ETO2 of 90% was 5.3 (95% CI: 3.2 to 8.9; P < 0.001). CONCLUSION Our study demonstrates that pre-oxygenation with HFNO is not a reliable method of pre-oxygenation before the induction of anaesthesia. TRIAL REGISTRATION clinical trial NCT03399695. Correspondence to Jean-Luc Hanouz, Service d'Anesthésie Réanimation (niveau 6), CHU de Caen, Av Côte de Nacre, 14033 CAEN Cedex, France E-mail: hanouz-jl@chu-caen.fr © 2019 European Society of Anaesthesiology

Modified ROTEM for the detection of rivaroxaban and apixaban anticoagulant activity in whole blood BACKGROUND Rapid detection of the anticoagulant effect of oral factor Xa (FXa) inhibitors may be essential in several emergency clinical situations. Specific assays quantifying the drugs are performed in plasma and require a turnaround time that is too long to be useful in emergency situations. Rotational thromboelastometry (ROTEM) is a whole blood coagulation assay of blood viscoelasticity and could be of interest for FXa inhibitor detection in emergency. However, conventional ROTEM reagents only detect high amounts of inhibitors. OBJECTIVE The aim of this study was first to assess the effect of whole blood components on the viscoelastic measurement of the effects of FXa inhibitors, an second to evaluate whether a modified ROTEM, triggered with a low amount of tissue factor and a saturating amount of phospholipid vesicles, can reliably detect low levels of FXa inhibitor activity in whole blood. DESIGN Diagnostic test study. SETTINGS A university research laboratory. From November 2014 to April 2016. PATIENTS Sixty-six patients: 30 treated with rivaroxaban, 17 with apixaban and 19 without treatment. INTERVENTION ROTEM was triggered with 2.5 pmol l−1 of tissue factor and 10 μmol l−1 of phospholipid vesicles. MAIN OUTCOME MEASURES Modified ROTEM parameters were measured in different experimental conditions: platelet-poor plasma (PPP), platelet-rich plasma, PPP supplemented with fibrinogen and reconstituted whole blood with various haematocrit levels adjusted between 30 and 60%. Modified ROTEM was further validated using whole blood from patients who were either treated or not treated with FXa inhibitors. RESULTS Modified ROTEM allowed detection of as little as 25 ng ml−1 FXa inhibitors in PPP, with at least a 1.4-fold increase of the clotting time (P ≤ 0.02). Neither changes of fibrinogen concentration nor variations of platelet count or haematocrit precluded FXa inhibitor detection. A lengthened modified ROTEM clotting time of more than 197 s allowed detection of FXa inhibitor concentrations above 30 ng ml−1 in whole blood with 90% sensitivity and 85% specificity. CONCLUSION Modified ROTEM may be applicable in emergency situations for the detection of FXa inhibitors in whole blood. Correspondence to Charles M. Samama, MD, PhD, FCCP, Department of Anaesthesia and Intensive Care Medicine, Cochin University Hospital, 27 rue du Faubourg St Jacques, 75014 Paris, France Tel: +33 1 42 34 85 51/+33 6 62 14 86 64; fax: +33 1 58 41 14 15; e-mail: marc.samama@aphp.fr Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Website (www.ejanaesthesiology.com). © 2019 European Society of Anaesthesiology