Anaesthesiology: a problem-based learning approach No abstract available

The role of goal-directed therapy in the prevention of acute kidney injury after major gastrointestinal surgery: Substudy of the OPTIMISE trial BACKGROUND Acute kidney injury (AKI) is an important adverse outcome after major surgery. Peri-operative goal-directed haemodynamic therapy (GDT) may improve outcomes by reducing complications such as AKI. OBJECTIVE To determine if GDT was associated with a reduced incidence of postoperative AKI according to specific renal biomarkers. DESIGN Prospective substudy of the OPTIMISE trial, a multicentre randomised controlled trial comparing peri-operative GDT to usual patient care. SETTING Four UK National Health Service hospitals. PATIENTS A total of 287 high-risk patients aged at least 50 years undergoing major gastrointestinal surgery. OUTCOME MEASURES The primary outcome measure was AKI defined as urinary neutrophil gelatinase-associated lipase (NGAL) at least 150 ng ml−1 24 and 72 h after surgery. Secondary outcomes were between-group differences in NGAL measurements and NGAL : creatinine ratios 24 and 72 h after surgery and AKI stage 2 or greater according to Kidney Disease Improving Global Outcomes (KDIGO) criteria within 30 days of surgery. RESULTS In total, 20 of 287 patients (7%) experienced postoperative AKI of KDIGO grade 2 or 3 within 30 days. The proportion of patients with urinary NGAL at least 150 ng ml−1 24 or 72 h after surgery was similar in the two groups [GDT 31/144 (21.5%) patients vs. usual patient care 28/143 (19.6%) patients; P = 0.88]. Absolute values of urinary NGAL were also similar at 24 h (GDT 53.5 vs. usual patient care 44.1 ng ml−1; P = 0.38) and 72 h (GDT 45.1 vs. usual patient care 41.1 ng ml−1; P = 0.50) as were urinary NGAL : creatinine ratios at 24 h (GDT 45 vs. usual patient care 43 ng mg−1; P = 0.63) and 72 h (GDT 66 vs. usual patient care 63 ng mg−1; P = 0.62). The incidence of KDIGO-defined AKI was also similar between the groups [GDT 9/144 (6%) patients vs. usual patient care 11/143 (8%) patients; P = 0.80]. CONCLUSION In this trial, GDT did not reduce the incidence of AKI amongst high-risk patients undergoing major gastrointestinal surgery. This may reflect improving standards in usual patient care. TRIAL REGISTRATION OPTIMISE Trial Registration ISRCTN04386758 Correspondence to Neil MacDonald, Department of Peri-operative Medicine and Pain, Royal London Hospital, London E1 1BB, UK Tel: +44 20 3594 0346; e-mail: n.macdonald2@nhs.net © 2019 European Society of Anaesthesiology

A comparison between the flexor hallucis brevis and adductor pollicis muscles in atracurium-induced neuromuscular blockade using acceleromyography: A prospective observational study BACKGROUND Neuromuscular blockade (NMB) monitoring is essential to avoid residual NMB. While the adductor pollicis is the recommended site for monitoring recovery, it is not always accessible. The flexor hallucis brevis could be an interesting alternative. OBJECTIVE The aim of our study was to compare NMB onset and recovery at both sites. DESIGN Prospective observational study. SETTING Operating rooms at the University Hospital of Poitiers, France. PATIENTS Sixty patients scheduled for surgery under general anaesthesia with neuromuscular blocking agents were enrolled from January 2016 to September 2017. Data from 56 patients were finally analysed. Among these, 11 patients received pharmacological reversal with neostigmine and atropine before emergence from anaesthesia. INTERVENTION After atracurium injection, NMB onset and recovery at the adductor pollicis and flexor hallucis brevis were monitored simultaneously. MAIN OUTCOME MEASURES The time to NMB onset, defined as a train-of-four (TOF) count equal to 0, and the times to NMB recovery: TOF = 1, TOF = 4, T4/T1 ratio = 0.75 and T4/T1 ratio more than 0.90. RESULTS NMB onset was significantly slower at the flexor hallucis brevis with a mean onset time of 4.4 ± 1.5 versus 3.7 ± 1.2 min at adductor pollicis (P = 0.0001). Recovery to TOF = 1 was significantly slower at flexor hallucis brevis. No difference was found for TOF = 4. The full recovery of NMB (T4/T1 > 0.90) was significantly faster at flexor hallucis brevis with a mean time to recovery of 59.5 ± 9.9 versus 64.5 ± 10.7 min at adductor pollicis (P < 0.0001), a difference of 4.9 min between both sites. This difference was not present after pharmacological reversal with a mean time to recovery of 53.0 ± 12.2 min at flexor hallucis brevis versus 54.0 ± 12.4 min at adductor pollicis (P = 0.28). However, NMB onset and recovery did not follow the same pattern in individual patients. CONCLUSION Flexor hallucis brevis could be an interesting alternative site for NMB monitoring when the adductor pollicis is not accessible. However, in the absence of pharmacological reversal, monitoring at the hallucis brevis muscle should be used with caution for the detection of residual paralysis. TRIAL REGISTRATION ClinicalTrials.gov (NCT02825121). Correspondence to Matthieu Boisson, Service d’anesthésie-réanimation, CHU de Poitiers, 2 rue de la Milétrie, 86021 Poitiers Cedex, France E-mail: matthieu.boisson@chu-poitiers.fr © 2019 European Society of Anaesthesiology

Thermochromic nail polish as a novel indicator to predict infraclavicular brachial plexus block success: A prospective cohort study BACKGROUND Skin temperature measurements after peripheral nerve block can be used as an easy and objective method to help predict block success. Thermochromic nail polishes are popular cosmetic products especially among young women. The colour change of nail polish is based on a thermochromic reaction as the temperature changes. OBJECTIVE The aim of this study was to test the hypothesis that the success of infraclavicular brachial plexus blocks (IBPBs) can be predicted by the colour change in thermochromic nail polish, which depends on skin temperature changes. DESIGN A prospective cohort study. SETTING Training and research hospital from December 2018 to March 2019. PATIENTS A total of 50 patients who received IBPB for forearm, wrist or hand surgery were included. MAIN OUTCOME MEASURES Thermochromic nail polish was applied to the nails of both hands of all patients before the block. Reaction of the nail polish in both hands was photographed immediately after application of nail polish and at 30 min after performing the block. The digital photographs of each patient were evaluated by observers. To evaluate the validity of the colour change in nail polish in predicting a successful IBPB, sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios were estimated. RESULTS The positive predictive value for colour change in thermochromic nail polish predicting a successful IBPB was 96% [95% confidence interval (CI) 90 to 98] and sensitivity was 94% (95% CI 87 to 97). Fleiss kappa value showed substantial agreement (0.76; 95% CI 0.59 to 0.93) in the assessment of interobserver agreement. CONCLUSION The current study demonstrates that the colour change in thermochromic nail polish is a valid and reliable indicator for the prediction of block success. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT03767868. Correspondence to Ali S. Kavakli, MD, Department of Anaesthesiology and Reanimation, University of Health Sciences, Antalya Training and Research Hospital, Antalya Egitim ve Arastirma Hst, Varlik Mh. Kazim Karabekir Cd., 07100 Antalya, Turkey Tel: +90 505 6775121; fax: +90 242 2494462; e-mail: alisaitkavakli@hotmail.com © 2019 European Society of Anaesthesiology

Fibrinolytic shutdown diagnosed with rotational thromboelastometry represents a moderate form of coagulopathy associated with transfusion requirement and mortality: A retrospective analysis BACKGROUND Viscoelastic techniques have made it possible to describe specific fibrinolytic phenotypes (physiological, hyperfibrinolysis and shutdown) and to establish a relationship of these phenotypes with outcome. However, there remains a debate as to whether shutdown is a state of hypercoagulability or rather a coagulopathy with moderate fibrinolysis and fibrinogen consumption. OBJECTIVES Our objectives were to describe the relationship between fibrinolytic phenotypes and outcomes, and to report the effects of tranexamic acid (TXA) administration. DESIGN This was a retrospective analysis of prospectively acquired data from a trauma registry. SETTING An academic level 1 trauma centre in the Lyon Region, from March 2011 to December 2016. PATIENTS We included all injured patients who had a rotational thromboelastometry analysis at admission. Fibrinolytic phenotypes were determined according to the maximum lysis: shutdown less than 3%, physiological 3 to 15%, hyperfibrinolysis more than 15%. MAIN OUTCOME MEASURE Mortality at 24 h and at hospital discharge. RESULTS During the study period, 473 patients were included with the following phenotypes: physiological (344 patients, 73%), shutdown (107 patients, 23%) and hyperfibrinolysis (22 patients, 5%). There was an increase in injury severity, prothrombin time ratio, fibrin degradation products and transfusion requirements from the physiological to the shutdown and hyperfibrinolysis phenotypes. Prehospital TXA administration increased the rate of shutdown and decreased the maximum lysis value at admission. After adjustment, multivariate analysis showed that fibrinolytic phenotypes, but not TXA, were independently associated with an increased risk of early death and death before hospital discharge: shutdown [odds ratio (95% confidence interval)] 2.4 (1.2 to 4.8) and hyperfibrinolysis 67.9 (7.4 to 624.2). CONCLUSION The results of the current study suggest that shutdown, which is associated with injury severity and mortality, probably reflects a moderate form of coagulopathy and fibrinolysis rather than a hypercoagulopathy. Therefore, the observation of shutdown fibrinolysis on thromboelastography/rotational thromboelastometry should not lead to withholding but rather to the administration of TXA. Correspondence to Jean-Stephane David, Département d’Anesthésie Réanimation, Centre Hospitalier Lyon Sud, F-69495 Lyon, France E-mail: js-david@univ-lyon1.fr © 2019 European Society of Anaesthesiology

A novel method for ultrasound-guided radial artery cannulation in neonates by trainee anaesthesiologists: A randomised controlled trial BACKGROUND The modified dynamic needle tip positioning (MDNTP) technique for ultrasound-guided radial artery cannulation (MDNTP-US technique) in neonates can be technically challenging for trainee anaesthesiologists. We hypothesised that by associating the MDNTP-US technique with hypodermic 0.9% sodium chloride (Saline MDNTP-US technique), which increases the subcutaneous radial artery depth, the procedure would become easier for trainee anaesthesiologists. OBJECTIVE To compare the Saline MDNTP-US technique, with the MDNTP-US technique for radial artery catheterisation in neonates by trainee anaesthesiologists with limited experience. DESIGN Randomised controlled trial. PATIENTS Ninety-six neonates scheduled to undergo major abdominal surgery requiring continuous arterial pressure monitoring between May 2018 and December 2018 at the Children's Hospital of Chongqing Medical University were enrolled. Neonates with signs of skin erosions or haematomas at or near the insertion site, as well as those with low noninvasive blood pressure values, were excluded. INTERVENTION Neonates were randomised to the Saline MDNTP-US and MDNTP-US groups in a 1 : 1 ratio. Twelve trainees performed the cannulation procedures. MAIN OUTCOME MEASURES Duration of procedure, first attempt success rate, rate of success within 10 min, and the incidence of haematoma and thrombosis. RESULTS The median [IQR] time to perform cannulation was less for the Saline MDNTP-US technique than for the MDNTP-US technique: 203 [160 to 600] vs. 600 s [220 to 600]; P = 0.005. The rate of success within 10 min, 72.9 vs. 47.9%; P = 0.012, was higher in the Saline MDNTP-US group than in the MDNTP-US group. The incidence of haematoma on postoperative day 1 was lower in the Saline MDNTP-US group than in the MDNTP-US group: 8.3 vs. 22.9%; P = 0.049. CONCLUSION Trainee anaesthesiologists can achieve higher success rates by using the Saline MDNTP-US technique instead of the MDNTP-US technique for radial artery catheterisation in neonates, taking less time with a lower incidence of complications. TRIAL REGISTRATION ChiCTR-IOR-17014119 (Chinese Clinical Trial Registry). Correspondence to Dr Lifei Liu, Department of Anesthesiology, Children's Hospital of Chongqing Medical University, 136 Zhongshan Er Road, Yu Zhong District, Chongqing 400014, PR China Tel: +86 18996218065; fax: +86 2363632143; e-mail: lifeiliu@hospital.cqmu.edu.cn © 2019 European Society of Anaesthesiology

Neuroanesthesia: A Problem-Based Learning Approach No abstract available

Incidence and risk factors of postoperative delirium in patients admitted to the ICU after elective intracranial surgery: A prospective cohort study BACKGROUND Postoperative delirium (POD) has been confirmed as an important complication after major surgery. However, neurosurgical patients have usually been excluded in previous studies. To date, data on POD and risk factors in patients after intracranial surgery are scarce. OBJECTIVES To determine the incidence and risk factors of POD in patients after intracranial surgery. DESIGN Prospective cohort study. SETTING A neurosurgical ICU of a university-affiliated hospital, Beijing, China. INTERVENTIONS Adult patients admitted to the ICU after elective intracranial surgery under general anaesthesia were consecutively enrolled between 1 March 2017 and 2 February 2018. Delirium was assessed using the Confusion Assessment Method for the ICU. POD was diagnosed as Confusion Assessment Method for the ICU positive on either postoperative day 1 or day 3. Patients were classified into groups with or without POD. Data were collected for univariate and multivariate analyses to determine the risk factors for POD. RESULTS A total of 800 patients were included. POD was diagnosed in 157 patients (19.6%, 95% confidence interval 16.9 to 22.4%). Independent risk factors for POD included age, nature of intracranial lesion, frontal approach craniotomy, duration of surgery, presence of an episode of low pulse oxygenation at ICU admission, presence of inadequate emergence and emergence delirium, postoperative pain and presence of immobilising events. POD was associated with adverse outcomes and high costs. CONCLUSION POD is prevalent in patients after elective intracranial surgery. The identified risk factors for and the potential association of POD with adverse outcomes suggest that a comprehensive strategy involving screening for predisposing factors and early prevention of modifiable factors should be established in this population. TRIAL REGISTRATION The study was registered at ClinicalTrials.gov (NCT03087838). Correspondence to Jian-Xin Zhou, Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, No 6, Tiantan Xili, Dongcheng District, Beijing 100050, China Tel: +86 10 67098019; fax: +86 10 67098019; e-mail: zhoujx.cn@icloud.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

Transcutaneous carbon dioxide measurements in fruits, vegetables and humans: A prospective observational study BACKGROUND Transcutaneous carbon dioxide measurement (TcCO2) is frequently used as a surrogate for arterial blood gas sampling in adults and children with critical illness. Data from noninvasive TcCO2 monitoring assists with clinical decisions regarding mechanical ventilation settings, estimation of metabolic consumption and determination of adequate end-organ tissue perfusion. OBJECTIVES To report TcCO2 values obtained from various fruits, vegetables and elite critical care medicine specialists. DESIGN Prospective, observational, nonblinded cohort study. SETTINGS Single-centre, tertiary paediatric referral centre and organic farmers’ market. PARTICIPANTS Vegetables and fruits included 10 samples of each of the following: red delicious apple (Malus domestica), manzano banana (Musa sapientum), key lime (Citrus aurantiifolia), miniature sweet bell pepper (Capsicum annuum), sweet potato (Ipomoea batatas) and avocado (Persea americana). Ten human controls were studied including a paediatric intensivist, a paediatric inpatient hospital physician, four paediatric resident physicians and four paediatric critical care nurses. INTERVENTIONS None. MAIN OUTCOME MEASURES TcCO2 values for each species and device response times. RESULTS TcCO2 readings were measurable in all study species except the sweet potato. Mean ± SD values of TcCO2 for human controls [4.34 ± 0.37 kPa (32.6 ± 2.8 mmHg)] were greater than apples [3.09 ± 0.19 kPa (23.2 ± 1.4 mmHg), P < 0.01], bananas [2.73 ± 0.28 kPa (20.5 ± 2.1 mmHg), P < 0.01] and limes [2.76 ± 0.52 kPa (20.7 ± 3.9 mmHg), P < 0.01] but no different to those of avocados [4.29 ± 0.44 kPa (32.2 ± 3.3 mmHg), P = 0.77] and bell peppers [4.19 ± 1.13 kPa (31.4 ± 8.5 mmHg), P = 0.68]. Transcutaneous response times did not differ between research cohorts and human controls. CONCLUSION We found nonroot, nontuberous vegetables to have TcCO2 values similar to that of healthy, human controls. Fruits yield TcCO2 readings, but substantially lower than human controls. Correspondence to Anthony A. Sochet, MD, MS, Assistant Professor of Anesthesiology and Critical Care Medicine, Division of Pediatric Critical Care Medicine, Johns Hopkins University, Johns Hopkins All Children's Hospital, 501 6th Ave S., St#: 702A, St. Petersburg, FL 33701, USA Tel: +1 727 767 2912; e-mail: anthony.sochet@jhmi.edu © 2019 European Society of Anaesthesiology

The concept of peri-operative medicine to prevent major adverse events and improve outcome in surgical patients: A narrative review Peri-operative Medicine is the patient-centred and value-based multidisciplinary peri-operative care of surgical patients. Peri-operative stress, that is the collective response to stimuli occurring before, during and after surgery, is, together with pre-existing comorbidities, the pathophysiological basis of major adverse events. The ultimate goal of peri-operative medicine is to promote high quality recovery after surgery. Clinical scores and/or biomarkers should be used to identify patients at high risk of developing major adverse events throughout the peri-operative period. Allocation of high-risk patients to specific care pathways with peri-operative organ protection, close surveillance and specific early interventions is likely to improve patient-relevant outcomes, such as disability, health-related quality of life and mortality. Correspondence to Bernardo Bollen Pinto, MD, PhD, Division of Anaesthesiology, Department of Anaesthesiology, Pharmacology, Intensive Care and Emergency Medicine, University Hospitals of Geneva, Gabrielle-Perret-Gentil 4, 1205 Geneva, Switzerland Tel: +41 789401810; fax: +41 223727511; e-mail: bernardo.bollenpinto@hcuge.ch © 2019 European Society of Anaesthesiology