Anaesthesiology

Effect of positive end-expiratory pressure on gastric insufflation during induction of anaesthesia when using pressure-controlled ventilation via a face mask: A randomised controlled trial BACKGROUND Face mask ventilation (FMV) during induction of anaesthesia is associated with risk of gastric insufflation that may lead to gastric regurgitation and pulmonary aspiration. A continuous positive airway pressure (CPAP) has been shown to reduce gastric regurgitation. We therefore hypothesised that CPAP followed by FMV with positive end-expiratory pressure (PEEP) during induction of anaesthesia would reduce the risk of gastric insufflation. OBJECTIVE The primary aim was to compare the incidence of gastric insufflation during FMV with a fixed PEEP level or zero PEEP (ZEEP) after anaesthesia induction. A secondary aim was to investigate the effects of FMV with or without PEEP on upper oesophageal sphincter (UES), oesophageal body and lower oesophageal sphincter (LES) pressures. DESIGN A randomised controlled trial. SETTING Single centre, Department of Anaesthesia and Intensive Care, Örebro University Hospital, Sweden. PARTICIPANTS Thirty healthy volunteers. INTERVENTIONS Pre-oxygenation without or with CPAP 10 cmH2O, followed by pressure-controlled FMV with either ZEEP or PEEP 10 cmH2O after anaesthesia induction. MAIN OUTCOME MEASURES A combined impedance/manometry catheter was used to detect the presence of gas and to measure oesophageal pressures. The primary outcome measure was the cumulative incidence of gastric insufflation, defined as a sudden anterograde increase in impedance of more than 1 kΩ over the LES. Secondary outcome measures were UES, oesophageal body and LES pressures. RESULTS The cumulative incidence of gastric insufflation related to peak inspiratory pressure (PIP), was significantly higher in the PEEP group compared with the ZEEP group (log-rank test P < 0.01). When PIP reached 30 cmH2O, 13 out of 15 in the PEEP group compared with five out of 15 had shown gastric insufflation. There was a significant reduction of oesophageal sphincter pressures within groups comparing pre-oxygenation to after anaesthesia induction, but there were no significant differences in oesophageal sphincter pressures related to the level of PEEP. CONCLUSION Contrary to the primary hypothesis, with increasing PIP the tested PEEP level did not protect against but facilitated gastric insufflation during FMV. This result suggests that PEEP should be used with caution after anaesthesia induction during FMV, whereas CPAP during pre-oxygenation seems to be safe. TRIAL REGISTRATION ClinicalTrials.gov, identifier: NCT02238691. 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 Per Cajander, Department of Anaesthesia and Intensive Care Örebro University Hospital, Södra Grev-Rosengatan, 701 85, Örebro, Sweden Tel: +46 19 602 03 53; e-mail: per.cajander@regionorebrolan.se © 2019 European Society of Anaesthesiology

Effect of sevoflurane-based or propofol-based anaesthesia on the incidence of postoperative acute kidney injury: A retrospective propensity score-matched analysis BACKGROUND Propofol may help to protect against ischaemic acute kidney injury (AKI); however, research on this topic is sparse. OBJECTIVE The current study aimed to investigate whether there were differences in the incidence of postoperative AKI after lung resection surgery between patients who received propofol-based total intravenous anaesthesia (TIVA) and those who received sevoflurane-based inhalational anaesthesia. DESIGN A retrospective observational study. SETTING A single tertiary care hospital. PATIENTS Medical records of patients aged 19 years or older who underwent curative lung resection surgery for nonsmall cell lung cancer between January 2005 and February 2018 were examined. MAIN OUTCOME MEASURES After propensity score matching, the incidence of AKI in the first 3 postoperative days was compared between patients who received propofol and those who received sevoflurane. Logistic regression analyses were also used to investigate whether propofol-based TIVA lowered the risk of postoperative AKI. RESULTS The analysis included 2872 patients (1477 in the sevoflurane group and 1395 in the propofol group). After propensity score matching, 661 patients were included in each group; 24 (3.6%) of the 661 patients in the sevoflurane group developed AKI compared with 23 (3.5%) of the 661 patients in the propofol group (95% confidence intervals of difference in incidence −0.019 to 0.022, P = 0.882). The logistic regression analyses revealed that the incidence of AKI was not different in the two groups (odds ratio 0.96, 95% confidence interval 0.53 to 1.71, P = 0.882). CONCLUSION In this retrospective study, no significant difference was found in the incidence of postoperative AKI after lung resection surgery between patients who received propofol-based TIVA and those who received sevoflurane-based inhalational anaesthesia. Considering the methodological limitation of this retrospective study, further studies are required to confirm these results. Correspondence to Tak Kyu Oh, Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, 166, Gumi-ro, Bundang-gu, Seongnam-si 13620, Gyeonggi-do, South Korea Tel: +82 31 787 7501; 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

Colour Doppler ultrasound after major cardiac surgery improves diagnostic accuracy of the pulmonary infection score in acute respiratory failure: A prospective observational study BACKGROUND Postoperative pneumonia is a frequent complication after cardiac surgery, and its diagnosis is difficult. Little is known about the diagnostic accuracy of lung ultrasound (LUS) in the detection of pneumonia in cardiac surgical patients. The substitution of chest radiography by colour Doppler LUS (LUS-sCPIS) in the simplified clinical pulmonary infection score (sCPIS) could improve the diagnosis of pneumonia following cardiac surgery. OBJECTIVE The aim of this study was to compare the diagnostic accuracy of LUS-sCPIS and of sCPIS alone in the detection of postoperative pneumonia after cardiac surgery. DESIGN A prospective study of diagnostic accuracy. SETTING A Surgical Intensive Care Unit of a French University Hospital. PATIENTS Fifty-one patients with acute respiratory failure within 72 h after cardiac surgery were enrolled between January and May 2015. MAIN OUTCOME MEASURE The two index tests, LUS-sCPIS and sCPIS, were calculated for all patients at the onset of acute respiratory failure. The reference standard for the diagnosis of pneumonia was based on the consensus of three physicians, blind to the sCPIS and LUS-sCPIS data, based on a posthoc review of all the clinical, radiological and microbiological evidence. The diagnostic accuracy of LUS-sCPIS was compared with that of sCPIS in the detection of postoperative pneumonia. RESULTS Pneumonia was diagnosed in 26 out of 51 patients. The LUS-sCPIS detected the presence of pneumonia with a sensitivity of 92% (95% CI 0.85 to 0.99) and a specificity of 68% (95% CI 0.55 to 0.81). The sCPIS detected the presence of pneumonia with a sensitivity of 35% (95% CI 0.22 to 0.48) and a specificity of 84% (95% CI 0.74 to 0.94). The area under the curve (AUC) of LUS-sCPIS at 0.80 (95% CI 0.69 to 0.91) was higher than the AUC of sCPIS at 0.59 (95% CI 0.47 to 0.71; P = 0.0008). CONCLUSION Compared with sCPIS, LUS-sCPIS improved diagnostic accuracy in the detection of postoperative pneumonia in patients with acute respiratory failure after cardiac surgery. It could be a useful bedside tool to guide pneumonia management. TRIAL REGISTRATION Clinicaltrials.gov identifier: NCT03279887. https://clinicaltrials.gov/ct2/show/NCT03279887?term=bougl%C3%A9&rank=4 Correspondence to Adrien Bouglé, MD, PhD, Département d’Anesthésie et de Réanimation, Réanimation de Chirurgie Cardiaque, Institut de Cardiologie, Hôpital Universitaire La Pitié-Salpêtrière, 47–83 boulevard de l’Hôpital, Paris 75013, France; e-mail: adrien.bougle@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

Reintubation in the ICU following cardiac surgery: is it more difficult than first-time intubation in the operating room?: A prospective, observational study BACKGROUND After cardiac surgery, a patient's trachea is usually extubated; however, 2 to 13% of cardiac surgery patients require reintubation in the ICU. OBJECTIVE The objective of this study was to compare the initial intubation in the cardiac operating room with reintubation (if required) in the ICU following cardiac surgery. DESIGN A prospective, observational study. SETTING Department of Anesthesiology and Intensive Care Medicine, Clinical Hospital of Santiago, Spain. PATIENTS With approval of the local ethics committee, over a 44-month period, we prospectively enrolled all cardiac surgical patients who were intubated in the operating room using direct laryngoscopy, and who required reintubation later in the ICU. MAIN OUTCOME MEASURES The primary endpoint was to compare first-time success rates for intubation in the operating room and ICU. Secondary endpoints were to compare the technical difficulties of intubation (modified Cormack–Lehane glottic view, operator-reported difficulty of intubation, need for support devices for direct laryngoscopy) and the incidence of complications. RESULTS A total of 122 cardiac surgical patients required reintubation in the ICU. Reintubation was associated with a lower first-time success rate than in the operating room (88.5 vs. 97.6%, P = 0.0048). Reintubation in the ICU was associated with a higher incidence of Cormack–Lehane grades IIb, III or IV views (34.5 vs. 10.7%, P < 0.0001), a higher incidence of moderate or difficult intubation (17.2 vs. 6.5%, P = 0.0001) and a greater need for additional support during direct laryngoscopy (20.5 vs. 10.7%, P = 0.005). Complications were more common during reintubations in the ICU (39.3 vs. 5.7%, P < 0.0001). CONCLUSION Compared with intubations in the operating room, reintubation of cardiac surgical patients in the ICU was associated with more technical difficulties and a higher incidence of complications. CLINICAL TRIAL NUMBER Ethics committee of Galicia number 2015-012. Correspondence to Dr Manuel Taboada, Department of Anesthesiology and Intensive Care Medicine, Servicio de Anestesiología y Reanimación del Hospital Clínico Universitario de Santiago de Compostela, Choupana sn, CP:15706 Santiago de Compostela, A Coruña, España Tel: +00 34 678195618; e-mail: manutabo@yahoo.es © 2019 European Society of Anaesthesiology

Propofol intravenous anaesthesia with desflurane compared with desflurane alone on postoperative liver function after living-donor liver transplantation: A randomised controlled trial BACKGROUND Propofol is an anaesthetic that resembles α-tocopherol and it has been suggested that it protects against ischaemia-reperfusion injury in liver transplantation. Living-donor liver transplantation (LDLT) presents an opportunity to test this hypothesis in both donors and recipients. OBJECTIVES We compared clinical outcomes after LDLT following anaesthesia with propofol and desflurane against desflurane alone. DESIGN A prospective, randomised, parallel study. SETTING Single-centre trial, study period June 2014 and May 2017. PATIENTS Sixty-two pairs of adult donors and recipients who underwent LDLT. INTERVENTION Patients were randomised to receive either desflurane balanced anaesthesia or propofol total intravenous anaesthesia combined with desflurane anaesthesia. MAIN OUTCOME MEASURES The primary outcome was peak liver transaminase levels during the first 7 days after surgery. Liver function was assessed at 10 different time-points (before surgery, 1 h after reperfusion, upon arrival in the ICU, and daily until postoperative day 7). Creatinine was measured to evaluate the incidence of acute kidney injury. TNF-α, IL-1β, IL-6 and TGF-β1 were assessed in 31 donors after induction, at hepatectomy and at the end of surgery and in 52 recipients after induction, and 1, 3 and 24 h after reperfusion. RESULTS Peak liver transaminase levels were not significantly different between the two groups. Liver function tests and creatinine were also similar between groups at all time-points. There was no difference in the incidence of postoperative complications, including acute kidney injury. With the exception of higher TNF-α in donors of the Propofol group at hepatectomy (0.60 ± 0.29 vs. 1.03 ± 0.53, P = 0.01) cytokine results were comparable between the two groups. CONCLUSION Despite the simultaneous administration of propofol infusion in both donors and recipients, no improvement in laboratory or surgical outcome was observed after LDLT compared with patients who received desflurane anaesthesia alone. TRIAL REGISTRATION NCT02504138 at clinicaltrials.gov. Correspondence to Young C. Yoo, Department of Anesthesiology and Pain Medicine, Severance Hospital, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, South Korea Tel: +82 2 2228 2420; fax: +82 2 2227 7897; e-mail: seaoyster@yuhs.ac © 2019 European Society of Anaesthesiology

Can quantitative sensory tests predict failed back surgery?: A prospective cohort study BACKGROUND Failed back surgery syndrome (FBSS) is a pain condition refractory to therapy, and is characterised by persistent low back pain after spinal surgery. FBSS is associated with severe disability, low quality of life and high unemployment. We are currently unable to identify patients who are at risk of developing FBSS. Patients with chronic low back pain may display signs of central hypersensitivity as assessed by quantitative sensory tests (QST). This can contribute to the risk of developing persistent pain after surgery. OBJECTIVE We tested the hypothesis that central hypersensitivity as assessed by QST predicts FBSS. DESIGN AND SETTING We performed a prospective cohort study in three tertiary care centres with 141 patients scheduled for up to three segment spinal surgery for chronic low back pain due to degenerative changes. PATIENTS Chronic low back pain was defined as at least 3 on a numerical rating scale on most days during the week and with a minimum duration of 3 months. OUTCOMES We defined FBSS as persistent pain, persistent disability or a composite outcome defined as either persistent pain or disability. The primary outcome was persistent pain 12 months after surgery. We applied 14 QST using electrical, pressure and temperature stimulation to predict FBSS and assessed the association of QST with FBSS in multivariable analyses adjusted for sociodemographic, psychological and clinical and surgery-related characteristics. RESULTS None of the investigated 14 QST predicted FBSS, with 95% confidence intervals of crude and adjusted associations of all QST including one as a measure of no association. Results remained robust in all sensitivity and secondary analyses. CONCLUSION The study indicates that assessment of altered central pain processing using current QST is unlikely to identify patients at risk of FBSS and is therefore unlikely to inform clinical decisions. Correspondence to Prof. Michele Curatolo, MD, PhD, Department of Anesthesiology and Pain Medicine, University of Washington, 1959 NE Pacific Street, Box 356540 Seattle, WA 98195-6540, USA Tel: +1 206 543 2568; fax: +1 206 543 2958; e-mail: curatolo@uw.edu 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

Tidal volume challenge to predict fluid responsiveness in the operating room: A prospective trial on neurosurgical patients undergoing protective ventilation BACKGROUND Pulse pressure variation (PPV) and stroke volume variation (SVV) do not predict fluid responsiveness when using a protective ventilation strategy: the use of functional haemodynamic tests can be useful to overcome this limitation. OBJECTIVES We tested the use of a tidal volume challenge (VTC), during 6 ml kg−1 [predicted body weight (PBW)] ventilation, and the end-expiratory occlusion test (EEOT) for prediction of fluid responsiveness. DESIGN An interventional prospective study. SETTING Supine elective neurosurgical patients. INTERVENTIONS The study protocol was, first, the initial EEOT test was performed during baseline 6 ml kg−1 PBW ventilation; second, VTC was performed by increasing the VT up to 8 ml kg−1 PBW and PPV and SVV changes were recorded after 1 min; third, a second EEOT was performed during 8 ml kg−1 PBW ventilation; and VT was reduced back to 6 ml kg−1 PBW and a third EEOT was performed. Finally, a 250 ml fluid challenge was administered over 10 min to identify fluid responders (increase in stroke volume index ≥10%). RESULTS In the 40 patients analysed, PPV and SVV values at baseline and EEOT performed at 6 ml kg−1 PBW did not predict fluid responsiveness. A 13.3% increase in PPV after VTC predicted fluid responsiveness with a sensitivity of 94.7% and a specificity of 76.1%, while a 12.1% increase in SVV after VTC predicted fluid responsiveness with a sensitivity of 78.9% and a specificity of 95.2%. After EEOT performed at 8 ml kg−1 PBW, a 3.6% increase in cardiac index predicted fluid responsiveness with a sensitivity of 89.4% and a specificity of 85.7%, while a 4.7% increase in stroke volume index (SVI) with a sensitivity of 89.4% and a specificity of 85.7%. CONCLUSION The changes in PPV and SVV obtained after VTC are reliable and comparable to the changes in CI and SVI obtained after EEOT performed at 8 ml kg−1 PBW in predicting fluid responsiveness in neurosurgical patients. TRIAL REGISTRATION ACTRN12618000351213. Correspondence to Antonio Messina, MD, PhD, Department of Anaesthesia and Intensive Care Medicine, IRCCS Humanitas, Humanitas University, Via Alessandro Manzoni, 56, Rozzano – Milan 20089, Italy. Tel: +39(0)2 8224 8282; e-mail: mess81rc@gmail.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

Effect of pre-operative oral carbohydrate loading on recovery after day-case cholecystectomy: A randomised controlled trial BACKGROUND Pre-operative carbohydrate loading has been shown to reduce pre-operative discomfort and postoperative nausea and vomiting in general surgical patients. Few studies have considered day-case surgery. OBJECTIVE The aim of this prospective randomised study was to determine whether pre-operative carbohydrate loading enhanced recovery after day-case cholecystectomy. DESIGN A randomised controlled trial. SETTING Secondary care in a district general and a university hospital in Finland between 2013 and 2016. PATIENTS A total of 113 patients American Society of Anesthesiologists physical status I or II aged 18 to 70 undergoing day-case cholecystectomy were included in the study. Exclusion criteria were bleeding or coagulation disorders, BMI more than 40 kg m−2, dementia, insulin-treated diabetes, migraine, Meniere's disease or a history of alcohol or drug abuse. INTERVENTION The carbohydrate-rich drink group received oral carbohydrate (200 ml) 2 to 3 h before surgery, and the control (fasting) group fasted from midnight according to standard protocol. MAIN OUTCOME MEASURES Visual analogue scales (VAS) were used to score six forms of discomfort: the need for analgesia and antiemetics, the time to drinking, eating and first mobilisation after surgery and the time to discharge. Any hospital re-admission was also recorded. RESULTS The highest VAS scores were seen for mouth dryness and tiredness 2 h after surgery in the fasting group. There were no significant differences in any VAS scores between the study groups. No differences in time to mobilisation, need for pain or antiemetic medication or time to discharge were seen between the groups. CONCLUSION Compared with overnight fasting, pre-operative carbohydrate loading did not significantly enhance peri-operative well being or recovery in patients undergoing day-case cholecystectomy. TRIAL REGISTRATION Clinicaltrials.gov Identifier: NCT03757208. Correspondence to Heli Helminen, Senior Physician, Department of Surgery, Seinäjoki Central Hospital, Hanneksenrinne 7, 60220 Seinäjoki, Finland Tel: +358 64155888; e-mail: heli.helminen@epshp.fi © 2019 European Society of Anaesthesiology

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 NCT02118844 (www.clinicaltrial.gov). Correspondence to Prof. Thomas Fuchs-Buder, University de Lorraine, CHRU Nancy, Brabois University Hospital, Department of Anesthesiology & Critical Care, 7 allée du Morvan, Vandoeuvre-les-Nancy 54511, France; E-mail: t.fuchs-buder@chru-nancy.fr © 2019 European Society of Anaesthesiology

A randomised controlled pragmatic trial of acupressure therapy on quality of recovery after surgery BACKGROUND Acupressure therapy is associated with favourable efficacies on postoperative nausea, pain and sleep disturbance, although the quality of the evidence is generally low. No randomised clinical trial has yet assessed the effect of acupressure on postoperative quality of recovery (QoR). OBJECTIVE The objective was to study acupressure efficacy on patient-reported postoperative recovery. DESIGN We conducted a single centre, three-group, blind, randomised controlled, pragmatic trial assessing acupressure therapy on the PC6, LI4 and HT7 acupoints. PATIENTS Postoperative patients expected to stay in hospital at least 2 days after surgery. INTERVENTIONS In the acupressure group, pressure was applied for 6 min (2 min per acupoint), three times a day after surgery for a maximum of 2 postoperative days during the hospital stay. In the sham group, extremely light touch was applied to the acupoints. The third group did not receive any touch. MAIN OUTCOME MEASURES The primary outcome was the change in the QoR, using the QoR-15 questionnaire, between postoperative days 1 and 3. Key secondary outcomes included patients’ satisfaction, postoperative nausea and vomiting, pain score and opioid (morphine equivalent) consumption. Assessors for the primary and secondary endpoints were blind to the group allocation. RESULTS Overall, 163 patients were randomised (acupressure n=55, sham n=53, no intervention n=55). The mean (SD) postoperative change in QoR-15 did not differ statistically (P = 0.27) between the acupressure, sham and no intervention groups: 15.2 (17.8), 14.2 (21.9), 9.2 (21.7), respectively. Patient satisfaction (on a 0 to 10 scale) was statistically different (P = 0.01) among these three groups: 9.1 (1.5), 8.4 (1.6) and 8.2 (2.2), respectively. Changes in pain score and morphine equivalent consumption were not significantly different between the groups. CONCLUSION Two days of postoperative acupressure therapy (up to six treatments) did not significantly improve patient QoR, postoperative nausea and vomiting, pain score or opioid consumption. Acupressure, however, was associated with improved patient satisfaction. TRIAL REGISTRATION: ClinicalTrials.gov, identifier: NCT02762435. Correspondence to Eric Noll, MD, PhD, Department of Anesthesiology and Intensive Care, Hôpitaux Universitaires de Strasbourg, Avenue Molière, 67098 Strasbourg, France Tel: +33 3 88127076; fax: +33 3 88127074; e-mail: eric.noll@chru-strasbourg.fr © 2019 European Society of Anaesthesiology